Thèses sur le sujet « Stress ambientali »
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Ruggiero, Paola. « Analisi funzionale del gene UVR8 e suo ruolo nella risposta delle piante a stress ambientali ». Doctoral thesis, Universita degli studi di Salerno, 2015. http://hdl.handle.net/10556/2040.
Texte intégralPlants are sessile organisms and, therefore, are continuously subjected to environmental sub-optimal or stressful conditions. In an arid environment plants are challenging multiple stresses, such, as water shortage, excessive soil salinity, osmotic stress conditions and high light intensity, including an excess of ultraviolet light mainly (UV-B). To overcome these unfavorable conditions, plants have evolved different strategies to adapt to common osmotic stress and high UV-B light. Recently, the UV-B photoreceptor, UVR8 (UV RESISTANCE LOCUS 8), has been identified and its role in the plant response to UV-B largely clarified. Besides its role in UV-B signaling, we have demonstrated that the expression of UVR8 gene is strongly induced by osmotic and salt stress in wild type A. thaliana seedling (Fasano et al., 2014). Moreover, by using a "gain and loss of function" approach we have evidenced a role of the UVR8 gene in plant growth, development and differentiation: UVR8 overexpressing plants have a reduced vegetative growth (minor diameter of the rosette, smaller leaves, height less), while silenced plants are characterized by a higher growth and produce a large number of siliques and seeds (Fasano et al., 2009; 2010), reminiscent of the response SIMR (Stress Induced Morphogenic Response). The UVR8 protein is predominantly localized in the cytoplasm and in response to low UV-B doses only a small fraction monomerizes and translocates to the nucleus, where it acts as a transcriptional activator. Most of the UVR8 protein remains in the cytoplasmic proteins and it might exert additional cellular functions by interacting with other proteins involved in the complex plant response to environmental stresses. This project was aimed at the identification of putative proteins that interact with UVR8 protein, and to establish a functional role of these interactions in plant responses to osmotic stress. The main results are summarized below: 1. by using complementary approaches of proteomics and immunoprecipitation, several potential proteins that interact with the UVR8 protein were identified; in particular, our attention was focused on the proteins APX1 (Ascorbate peroxidase) and GGT1 (glutamate-glyoxylate-aminotransferase), known for their role in the mechanisms of detoxification of H2O2, a reactive oxygen species that accumulates in the plant cell in response to different environmental conditions that generate an oxidative stress; 2. the interaction between APX1-UVR8 and UVR8-GGT1 were confirmed in vivo, by using two different assays: the BiFC and the co-immunoprecipitation; 3. through a functional analysis, it was shown that different levels of the UVR8 protein are associated with a different level of ROS, in response to conditions of osmotic stress, suggesting a possible function associated to the interaction of these between UVR8 e APX1 4. a gene expression analysis of the stress marker gene RD29 and the gene GGT1 in UVR8- knock-out or overexpressing plants was performed, in response to salt stress. These experiments provided an early indication of the effect of different levels of the UVR8 protein on the transcriptional level of these two genes and, more generally, in the global response to salt stress in Arabidopsis plants. Further analyses are required to establish whether the interaction of UVR8 with APX1 or GGT1 might somehow influence their enzymatic activity. In addition, previous studies have shown that UVR8 binds to COP1 (an E3-ubiquitin ligase) and targets negative regulators of the UV-B dependent pathway to proteasome degradation (Huang X et al., 2013). The use of inhibitors of this proteoliytic pathway may contribute to determine whether UVR8 protein can recruit APX or GGT1 proteins in order to stabilize them or target them to the proteolytic degradation in response to direct or osmotic stress derived oxidative stress.
X n.s.
Fornasiero, Diego. « Influenza dei fattori ambientali e agronomici sulle popopolazioni di Empoasca Vitis (GOETHE) ». Doctoral thesis, Università degli studi di Padova, 2009. http://hdl.handle.net/11577/3426457.
Texte intégralNel presente lavoro sono stati valutati gli effetti di alcuni fattori ambientali ed agronomici sulla dinamica delle popolazioni di Empoasca vitis (Göthe) (Homoptera: Cicadellidae), specie potenzialmente dannosa alla vite. Il ciclo biologico di E. vitis è stato studiato, in alcuni vigneti situati nel Veneto orientale, nel triennio 2006-2008. Nel 2007, caratterizzato da temperature primaverili più elevate rispetto al 2006 e al 2008, si è verificato un forte anticipo nella fenologia della vite e nello sviluppo delle prime due generazioni di E. vitis. Questo fenomeno ha comportato, in un vigneto di collina, il probabile completamento di una quarta generazione, dato inedito per l’Italia. É stata valutata l’influenza della vegetazione spontanea sulla distribuzione spazio-temporale delle popolazioni di E. vitis e dei suoi parassitoidi oofagi (Anagrus gruppo atomus). I risultati evidenziano una distribuzione aggregata delle due specie in primavera, talvolta anche in estate. É stata osservata un’associazione positiva tra le due specie nelle prime fasi della stagione vegetativa. In primavera, le catture degli adulti di E. vitis sono risultate più elevate in prossimità del bosco e, in seguito, la distribuzione della specie è risultata più omogenea all’interno del vigneto. Le densità degli Anagrus sono state tendenzialmente più elevate nelle zone contigue al bosco. Questo comportamento può avere ripercussioni positive sugli equilibri biologici. Le forme di allevamento della vite possono esercitare effetti significativi sull’abbondanza di E. vitis. Nell’ambito di due aziende, sono state riscontrate popolazioni più elevate di E. vitis nei sistemi di allevamento a pergola e a Guyot, probabilmente perché caratterizzati da una struttura della chioma più omogenea. Altri studi hanno dimostrato che l’irrigazione ha un effetto positivo sull’abbondanza di E. vitis. Un confronto effettuato tra diversi sistemi di allevamento (goccia, subirrigazione, partial root-zone drying) ha posto in luce densità significativamente più elevate del fitomizo nella tesi caratterizzata dall’impianto a goccia rispetto alla tesi non irrigua ove si è verificato lo stress idrico più forte. A stress idrici moderati (subirrigazione e partial root-zone drying) sono corrisposte densità di popolazione intermedie. Gli studi eseguiti su piante di vite in vaso hanno evidenziato che stress idrici moderati riducono sia il potenziale riproduttivo di E. vitis sia la sopravvivenza delle uova del cicdadellide. Stress forti riducono drasticamente la sopravvivenza delle uova e le dimensioni della progenie. Presso una collezione di cultivar, sono state effettuate osservazioni sulle densità delle popolazioni di E. vitis e sull’intensità dei sintomi associati all’attività trofica del cicadellide. Carmènère e Sauvignon Blanc si sono dimostrate molto suscettibili, al contrario di Cabernet Sauvignon e Incrocio Manzoni 6.0.13. Alcune varietà sono risultate sia molto suscettibili sia molto sensibili e viceversa. Altre sono state associate ad un’incidenza marginale dei sintomi fogliari pur manifestando densità di popolazione significative. Tali acquisizioni possono risultare utili nelle strategie di monitoraggio delle popolazioni in ambito aziendale o territoriale. L’effetto dell’infestazione di E. vitis su alcuni parametri produttivi è stato analizzato su alcune cultivar in pieno campo. I dati raccolti hanno evidenziato che densità di popolazione simili possono essere associate a danni quanti-qualitativi diversi in funzione della cultivar. Infestazioni relativamente elevate hanno causato variazioni significative di alcuni parametri qualitativi (solidi solubili, acidità titolabile) sulle cultivar Merlot e Cabernet Franc. Relativamente al controllo chimico, è stata confermata l’inefficacia di chlorpyriphos-ethyl dovuta probabilmente a fenomeni di resistenza. Su queste popolazioni si sono dimostrati efficaci alcuni chitino-inibitori (flufenoxuron) e neonicotinoidi (thiamethoxam). Alcuni fungicidi possono esercitare effetti di una certa intensità sulle popolazioni di E. vitis, fenomeno che merita ulteriori conferme prima di essere sfrutttato in protezione integrata.
Forgiarini, Alessia. « Tossicità di inquinanti ambientali correlati ai processi di incenerimento dei rifiuti solidi urbani : studio dei meccanismi molecolari su cellule del tratto respiratorio ». Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3423654.
Texte intégralI moderni stili di vita portano alla produzione di una grande quantità di rifiuti, che tende costantemente ad aumentare (McKay, 2002). Il modo più efficace per tentare di risolvere questo problema è quello di ridurne il volume. Gli odierni inceneritori di rifiuti solidi urbani sono in grado di diminuire il volume e la massa dei rifiuti, ma le sostanze che vengono emesse possono essere altamente tossiche. I sottoprodotti che si formano, in particolare la frazione più leggera delle ceneri (Fly Ash), possono contenere alte quantità di metalli pesanti volatili, come Cd, Pb e Zn, oltre a diossine e furani (Yao et al., 2012). Il particolato atmosferico (PM) è un importante fattore di rischio ambientale e per la salute. Molti studi epidemiologici hanno infatti evidenziato una correlazione diretta tra l’esposizione al PM e l’insorgere di infezioni respiratorie acute, tumore polmonare e malattie croniche del tratto respiratorio e del sistema cardiovascolare (de Kok et al., 2006). Il Fly Ash, raccolto dal filtro a manica dell’inceneritore dei rifiuti solidi urbani di Bolzano, è stato utilizzato come modello di miscela di particelle a composizione complessa rilasciata in atmosfera, al fine di studiare il meccanismo delle risposte biologiche precoci di cellule epiteliali polmonari umane BEAS-2B e A549. Sono stati inoltre studiati alcuni campioni ottenuti da filtri di aria posti in diverse posizioni della città di Bolzano. Le analisi chimico-fisiche hanno permesso di identificare e quantificare gli inquinanti presenti, mentre i test in vitro di valutare gli effetti tossici del Fly Ash (Frazione Totale) e dei campioni d'aria. Gli studi hanno riguardato anche gli effetti di alcune frazioni derivate dal Fly Ash: Frazione Idrosolubile, Non-Idrosolubile e DMSO-solubile. L’esposizione alla Frazione Totale ha indotto una riduzione concentrazione-dipendente della crescita cellulare (in modo particolare delle cellule BEAS-2B) e un’aumentata produzione di ROS. Lo stress ossidativo indotto è stato confermato anche dalla diminuzione del contenuto di tGSH e dall’induzione dell’eme ossigenasi-1. Inoltre è in grado di innescare risposte infiammatorie con attivazione di NF-kB e aumento dei livelli di IL-6 e IL-8. I dati hanno confermato una forte correlazione tra la composizione dei campioni e i loro effetti biologici, infatti le frazioni Totale e Non-Idrosolubile si sono rivelate quelle più tossiche, mentre le frazioni Idrosolubile e DMSO-solubile sono quelle meno attive. Il pre-trattamento delle cellule con l'antiossidante N-acetilcisteina inibisce nettamente la produzione di ROS, la riduzione dei livelli di tGSH e la secrezione di IL, confermando così il coinvolgimento dello stress ossidativo nei meccanismi di tossicità indotti dal Fly Ash. I risultati ottenuti studiando alcuni campioni ottenuti da filtri di aria posti in diverse posizioni della città, sottolineano innanzitutto la buona efficienza dei sistemi di filtrazione dei fumi dell’inceneritore, in grado di diminuire notevolmente la quantità di IPA, diossine e soprattutto metalli emessi in atmosfera e quindi di limitarne i possibili danni. Tra i campioni studiati, influenzati in maniera più o meno importante dalla presenza di diverse fonti di emissione, tra cui l’inceneritore, solo quello ottenuto dal filtro posto a camino dell’impianto è in grado di attivare un’importante risposta ossidativa e infiammatoria, indicando un significativo contributo delle emissioni, in ogni caso inferiori ai limiti imposti dalle vigenti normative.
Foschini, Anna. « Effetto dei farmaci ambientali propranololo e carbamazepina sullo sviluppo larvale del mitilo, Mytilus galloprovincialis ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/9880/.
Texte intégralTasselli, Stefano. « Espressione di geni correlati allo stress ossidativo nell'ascidia coloniale Botryllus schlosseri esposta a diverse condizioni ambientali nella Laguna di Venezia ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9360/.
Texte intégralCavalcante, Dalita Gomes Silva Morais [UNESP]. « Biomarcadores genéticos e bioquímicos para avaliar os efeitos do biodiesel, por meio de bioensaios in vivo e in vitro ». Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/100533.
Texte intégralCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O biodiesel é um combustível definido como monoalquil éster de ácidos graxos de cadeia longa, derivado de fontes renováveis, tais como óleos vegetais ou gorduras animais. Com o aumento da utilização do biodiesel, cresce a preocupação acerca de seus efeitos sobre a saúde de seres humanos e outros organismos, porém poucos são os estudos na literatura sobre os possíveis efeitos biológicos decorrentes da contaminação de biodiesel. Assim, o objetivo deste trabalho foi tentar identificar biomarcadores relacionados com a presença de biodiesel, produzidos por duas diferentes rotas (etílica e metílica), utilizando como sistema teste o peixe neotropical Prochilodus lineatus e a linhagem celular derivada de hepatócitos de Zebrafish (ZFL). Os resultados obtidos nos testes in vivo com P. lineatus mostraram que ambas as frações solúveis do biodiesel (etílica e metílica), induziram aumento na produção de espécies reativas de oxigênio (ERO), causaram a ativação da enzima de biotransformação glutationa-S-transferase (GST) e da enzima antioxidante superóxido dismutase (SOD), além de aumentar a frequência de danos no DNA de células branquiais e eritrócitos nos peixes expostos. Além disso, a fração solúvel do biodiesel produzida por rota etilica causou aumento na concentração de glutationa reduzida (GSH) e a fração solúvel do biodiesel, produzida por rota metílica causou a ativação hepática das enzimas antioxidantes catalase (CAT) e glutationa peroxidase. Os resultados dos testes in vitro com ZFL mostraram que ambas as frações solúveis promoveram aumento na produção de ERO, ativação da enzima de biotransformação GST e danos na molécula de DNA nas células ZFL expostas. A fração solúvel do biodiesel produzida por rota metílica se mostrou mais citotóxica do que aquela produzida por rota etílica, além de produzir danos... (Resumo completo, clicar acesso eletrônico
Biodiesel fuel is defined as monoalkyl esters of long chain fatty acids derived from renewable sources such as vegetable oils or animal fats. With the increased use of biodiesel, growing concern about its effects on the health of humans and other organisms, but there are few studies in the literature that attempt to elucidate the possible biological effects resulting from contamination of biodiesel. The objective of this study was to try and identify biomarkers related to the presence of biodiesel produced by two different routes (methyl and ethyl), using as test system neotropical fish Prochilodus lineatus and cell line derived from Zebrafish hepatocytes (ZFL). The results obtained in vivo tests with P. lineatus showed that both soluble fractions of biodiesel (methyl and ethyl), induced increased production of reactive oxygen species (ROS), caused activation of biotransformation enzyme glutathione-S-transferase (GST) and antioxidant enzyme superoxide dismutase (SOD), and increase the frequency of DNA damage in gill cells and erythrocytes in fish exposed. Moreover, the soluble fraction of the biodiesel produced by ethylic route caused an increase in the concentration of reduced glutathione (GSH) and the soluble fraction of the biodiesel produced by methylic route caused the activation of hepatic antioxidant enzymes catalase (CAT) and glutathione peroxidase. The results of in vitro tests (ZFL) showed that both soluble fractions led to an increase in the production of ROS, activation of biotransformation enzyme GST and damage to the DNA molecule in ZFL cells exposed. The soluble fraction of the biodiesel produced by methylic route was more cytotoxic than that produced by ethylic route, besides producing oxidative damage in the DNA molecule. Based on these results, it is possible to infer that biodiesel can cause... (Complete abstract click electronic access below)
Cavalcante, Dalita Gomes Silva Morais. « Biomarcadores genéticos e bioquímicos para avaliar os efeitos do biodiesel, por meio de bioensaios in vivo e in vitro / ». Rio Claro : [s.n.], 2012. http://hdl.handle.net/11449/100533.
Texte intégralAbstract: Biodiesel fuel is defined as monoalkyl esters of long chain fatty acids derived from renewable sources such as vegetable oils or animal fats. With the increased use of biodiesel, growing concern about its effects on the health of humans and other organisms, but there are few studies in the literature that attempt to elucidate the possible biological effects resulting from contamination of biodiesel. The objective of this study was to try and identify biomarkers related to the presence of biodiesel produced by two different routes (methyl and ethyl), using as test system neotropical fish Prochilodus lineatus and cell line derived from Zebrafish hepatocytes (ZFL). The results obtained in vivo tests with P. lineatus showed that both soluble fractions of biodiesel (methyl and ethyl), induced increased production of reactive oxygen species (ROS), caused activation of biotransformation enzyme glutathione-S-transferase (GST) and antioxidant enzyme superoxide dismutase (SOD), and increase the frequency of DNA damage in gill cells and erythrocytes in fish exposed. Moreover, the soluble fraction of the biodiesel produced by ethylic route caused an increase in the concentration of reduced glutathione (GSH) and the soluble fraction of the biodiesel produced by methylic route caused the activation of hepatic antioxidant enzymes catalase (CAT) and glutathione peroxidase. The results of in vitro tests (ZFL) showed that both soluble fractions led to an increase in the production of ROS, activation of biotransformation enzyme GST and damage to the DNA molecule in ZFL cells exposed. The soluble fraction of the biodiesel produced by methylic route was more cytotoxic than that produced by ethylic route, besides producing oxidative damage in the DNA molecule. Based on these results, it is possible to infer that biodiesel can cause... (Complete abstract click electronic access below)
Orientador: Maria Aparecida Marin-Morales
Coorientador: Cláudia Bueno dos Reis Martinez
Banca: Carmem Silvia Fontanetti Christofoletti
Banca: Edson Luis Maistro
Banca: Grasiela Dias de Campos Severi Aguiar
Banca: Ilce Mara de Syllos Colus
Doutor
Alho, Ana Margarida Pignateli Vasconcelos de Assunção. « O enriquecimento ambiental como estratégia de tratamento e prevenção da cistite idiopática felina ». Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4064.
Texte intégralO Enriquecimento Ambiental Felino é um tema pouco abordado e, no entanto, de fácil implementação, baixo custo, sem contra-indicações, actuando como factor de prevenção e tratamento da Cistite Idiopática Felina. Pretendeu-se neste estudo compreender o grau de conhecimento dos proprietários de felinos sobre o conceito de Enriquecimento Ambiental, nomeadamente a informação que detêm e as medidas que implementam na prática. Foram aplicados 130 inquéritos no Hospital Escolar da Faculdade de Medicina Veterinária da Universidade Técnica de Lisboa (HEFMV-UTL), questionando a aplicação de 22 medidas de enriquecimento ambiental. Observou-se que 20% dos proprietários implementa apenas entre 5 a 9 medidas, 74,62% entre 10 a 14 e 5,38% entre 15 a 19. Não se observou nenhum caso com 20 ou mais medidas implementadas. Constatou-se que as mais aplicadas eram as referentes à higiene (remoção diária dos dejectos e localização dos caixotes de areia em zonas ventiladas e não-movimentadas), que estavam implementadas por questões de salubridade e comodidade dos proprietários, e não pelo seu efeito correctivo ou preventivo de afecções nos felinos. As medidas menos implementadas eram as que exigiam uma maior informação específica e disponibilidade por parte dos proprietários, nomeadamente a utilização de feromonas, de dispensadores de comida, de estímulos olfactivos, auditivos e visuais. Posteriormente, foi proposta e aplicada uma escala de classificação do ambiente doméstico felino, em que se verificou que o ambiente oferecido pela maioria dos proprietários (74,62%) era apenas medianamente enriquecido. Constatou-se que apenas 8,46% dos proprietários conhecia o conceito de enriquecimento ambiental felino. Outro dos objectivos deste estudo consistiu no desenvolvimento e aplicação de um inquérito para averiguação das fontes de stresse, possivelmente responsáveis, pelo despoletar da Cistite Idiopática nos felinos. Dos 10 casos encontrados no HEFMV-UTL, as fontes de stresse mais frequentemente identificadas pelos proprietários foram o conflito intra-espécie (3 casos), ausência dos proprietários (2 casos), mudança de habitação (1 caso), mudança de habitação e conflito intra-espécie (1 caso) e obras na habitação (1 caso). Uma vez que o Enriquecimento Ambiental Felino permite a redução e prevenção do stresse felino e, considerando que a sua implementação está longe do padrão ideal proposto na literatura, pretende-se com este trabalho fazer deste conceito uma prática comum e acessível, através da sua consciencialização e divulgação junto dos proprietários e da classe Médico-Veterinária.
ABSTRACT - Environmental Enrichment as a strategy of Treatment and Prevention of Feline Idiopathic Cystitis - Feline environmental enrichment is an issue receiving little attention in spite of its easy implementation, low-cost, no contraindications and acting as a factor of prevention and treatment of Feline Idiopathic Cystitis. The main aim of this study was to understand the state of owners’ knowledge on environmental enrichment, namely information they got and measures implemented in practice. One hundred and thirty questionnaires were applied at the Hospital of the Faculty of Veterinary Medicine - Technical University of Lisbon, inquiring about the application of twenty two measures of environmental enrichment. Results have shown that 20% of the owners implement only 5 to 9 measures, 74,62% implement 10 to 14, 5,38% implement 15 to 19, and no cases of 20 or more applied measures. Hygiene related measures (daily cleaning of litter boxes and their location in private and ventilated areas), were the most adopted by owners, mainly by reasons of owners’ health and convenience and not by its corrective and preventive effect in feline’s health. The less implemented measures were those requiring more specific information and owners commitment, such as pheromone use, food balls, and olfactory, auditory and visual enrichment. Later on, it was proposed and applied a rating scale of feline domestic environment, where it was reported an environmental enrichment of medium quality (74,62%). Also important was the fact that only 8,46% of the owners knew the concept of Feline environmental enrichment. Another purpose of this study was the development and application of a questionnaire regarding the sources of stress, possibly responsible for triggering Feline Idiopathic Cystitis. Out of the 10 cases found at the Faculty Hospital, the most frequent source of stress identified by owners was intra-species conflict (3 cases), lack of owners’ presence (2 cases), house changing (1 case), intra-species conflict and house changing (1 case) and house construction works (1 case). Since feline environmental enrichment allows feline stress reduction and prevention, and considering its implementation far from the ideal pattern proposed in literature, the purpose of this research is to contribute to the incorporation of this concept in the common practice, through awareness and the advertisement to the owners and veterinary doctors’ community.
Gregório, Rafaela Silva. « Relação entre a exposição a fatores ambientais stressantes e a Diabetes mellitus nos gatos ». Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2017. http://hdl.handle.net/10400.5/14548.
Texte intégralA Diabetes Mellitus é a endocrinopatia mais comum nos gatos, tipicamente a tipo 2, sendo que sua prevalência tem aumentado, devido à mudança de hábitos alimentares e vidas sedentárias. A falta de ou aplicação de estímulos inadequados, pode conduzir a stresse, com consequente produção de cortisol. Se aquele for reiterado, os níveis desta hormona aumentam gradualmente, o que poderá levar à resistência à insulina. Sendo assim, esta dissertação teve como objetivo averiguar se o stresse poderá ser um factor de risco para a diabetes. Desta forma, foi feito um questionário, aplicado a tutores de gatos diabéticos e não diabéticos, onde se pode avaliar sobre a sobrexposição do gato a fatores ambientais, potencialmente stressantes. Obtiveram-se dados de 88 gatos (n=88) e os grupos dos diabéticos (n=22) e não diabéticos (n=66) foram comparados. Foi encontrada associação entre alguns fatores e a doença (p<0,05). Nesses casos, foi feita uma regressão logística que permitiu aferir sobre o risco de ter diabetes, através dos valores de Odds Ratio obtidos. Assim, concluiu-se que, alguns fatores, aumentam o risco de manifestar diabetes. Situações como a presença de outras doenças, a co-habitação com mais gatos e o serem acolhidos por reformados/desempregados, aumentam em 5 vezes a probabilidade de manifestar diabetes. Gatos sedentários e com excesso de peso têm 6 e 4 vezes mais probabilidade de vir a ter diabetes, respetivamente. Quando comparados com os que brincam 1-2h/dia, aqueles que o fazem 0h ou 30 minutos, têm, respetivamente, 5 e 4 vezes mais probabilidade de ter diabetes. O acesso ao exterior também parece influenciar, de tal forma que, gatos que passam entre 0 a 1 hora por dia no exterior, têm 6 vezes mais risco de ter diabetes, quando comparados com aqueles que despendem 1 a 5 horas no exterior. Habitarem em apartamentos também aumenta em 3 vezes o risco de doença. O número e localização de recursos também podem ter influência nesta doença. Assim, caixas de areia localizadas no corredor aumentam a probabilidade da diabetes ocorrer em 14 vezes e um número de bebedouros inferior ou igual ao número de gatos, aumenta 15 e 7 vezes o risco de ter diabetes, quando comparado com ambientes em que o número de bebedouros é superior ao número de gatos. Contrariamente, gatos activos, com acesso a sítios para trepar têm cerca de 1/10 da probabilidade de ter diabetes. Uma mudança de água diária, ao invés de semanal, também diminui para 1/5 a probabilidade de ter diabetes. Em suma, perante os resultados, é possível afirmar que o stresse poderá ser um factor de risco para a Diabetes Mellitus.
ABSTRACT - The relationship between the exposure to stressful factors and Diabetes Mellitus in cats - Diabetes Mellitus is the most common endocrinopathy in cats, generally the type 2. Its prevalence has been increasing, due to the changes in diet habits and sedentary lifestyles. The lack of stimuli or their inappropriate appliance can lead to stress, with consequent cortisol production. If the stress is reiterated, this hormone’s levels gradually increase, which can conduct to insulin resistance, hence diabetes. So, this dissertation had the goal to evaluate if stress can be a risk factor to diabetes. This way, a survey was made, questioning tutors of diabetic and non-diabetic cats, about the cat’s exposure to certain stressful factors. Data from 88 (n=88) cats was gathered, 22 diabetics (n=22) and 66 controls (n=66). The statistical analysis allowed to find an association between the disease and the factors (p<0,05). In these cases, a statistical regression was made, to evaluated the risk of having diabetes, through the values of Odds Ratio. Some factors indeed increase the chances of manifesting diabetes in cats. Among these are, the presence of other diseases and the co-habitation with other cats, that increases 5 times the odds. Inactive and overweight cats have 6 and 4 times more risk of diabetes, respectively. When compared with cats that play 1-2 hours per day, those who play 0 hours or only 30 minutes, have 5 and 4 times more odds of manifesting diabetes, respectively. Exterior environment can also influence the presence of this disease. It appears that cats that only spend 0 to 1 hour per day outside, have 6 times more risk of becoming diabetic, when compared to cats that spend 1 to 5 hours in the exterior. Living in apartments also rises the chances of having diabetes to 3 times. The number and localization of basic resources can influence diabetes too. Litter boxes stationed in passage areas, like halls, increase 14 times the probability of having the disease. A number of drinkers equal or inferior to the number of cats living in one place, can increment the risk of diabetes 15 and 7 times, respectively, when compared with houses where the number of drinkers is superior to the number of cats. On other hand, some factors can reduce the probabilities of occurrence of diabetes. Active cats with access to climbing places have 1/10 of the changes of manifesting diabetes. Changing the water daily, instead of weekly, can reduce the risk having this endocrine imbalance 5 times. Therefore, scouting the results, it is possible to conclude that stress can, indeed be a risk factor to Diabetes Mellitus.
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Loureiro, Cláudia Sofia Brites. « Ecological interactions in populations facing environmental stress ». Doctoral thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10537.
Texte intégralO zooplâncton, particularmente os cladóceros, são organismos de água doce importantes na regulação da produção primária dos ecossistemas de água doce. No entanto, também podem adaptar-se a condições salobras. Tendo em conta as previsões no âmbito das alterações climáticas, a intrusão salina pode ocorrer a par com a subida de temperatura. As populações de água doce podem ficar vulneráveis aos efeitos interativos da salinidade e da temperatura, de acordo com os seus limites de tolerância e capacidade de adaptação ao stress ambiental. Assim, a presente tese analisou as interações resultantes das alterações destes agentes de stress em populações de cladóceros de água doce. Primeiro, comparou-se a halotolerância de diferentes genótipos de Simocephalus vetulus provenientes de populações de água doce e de água salobra de modo a avaliar a existência de uma componente genética de resistência à salinidade. A sensibilidade aguda dos genótipos variou na mesma gama de concentrações; todavia, todos os genótipos da população salobra, exceto um, foram mais tolerantes do que os de água doce, em termos de tempo à imobilização. Contudo, não foi possível estabelecer uma relação entre a performance reprodutiva em condições salobras e o contexto ambiental de origem destes genótipos. Mais, estes ensaios mostraram que as populações de água doce têm potencial para tolerar incrementos de salinidade. Como tal, pode-se concluir que a seleção a que os genótipos estão sujeitos no seu local de origem foi mais fraca do que o esperado. Segundo, investigou-se a capacidade de aclimatação de Daphnia galeata à salinidade e temperatura, de modo a avaliar a halotolerância de Daphnia a duas temperaturas num cenário de aclimatação multigeracional. O objetivo foi compreender se a pré-adaptação ao stress ambiental (20ºC e 25ºC versus 0 g/L e 1 g/L de NaCl) influenciou posteriormente as respostas a estes agentes de stress. Verificou-se uma tendência para um aumento de sensibilidade ao NaCl, a temperaturas mais elevadas. No entanto, este efeito foi anulado após nove gerações, mas apenas quando os organismos foram aclimatados aos dois agentes de stress em simultâneo (salinidade e temperatura elevada). Terceiro, demonstrou-se experimentalmente que a salinidade interferiu com a competição interespecífica, alterando a composição das comunidades zooplanctónicas. Este conjunto de evidências permitiu-nos refletir nos múltiplos impactos de agentes de stress, particularmente os relacionados com as previsões de alterações climáticas. Em paralelo aos estudos de natureza experimental, e numa perspetiva de Educação para o Desenvolvimento Sustentável (EDS), importa também promover o desenvolvimento de competências necessárias à compreensão de mudanças ambientais globais (e.g., o impacto da salinidade e da temperatura) para implementar estratégias de mitigação e adaptação. Neste contexto, foi realizada uma atividade com estudantes do ensino secundário, que se tornou uma boa oportunidade para a sua aprendizagem e aquisição de competências de interpretação de dados experimentais, assim como de sensibilização para as questões ambientais.
Zooplankton, namely cladocerans, are important regulators of primary production in freshwater ecosystems. However, these filter-feeders can also be found in brackish waters and can therefore adapt to this stressful condition. Bearing in mind climate change predictions, saline intrusion can occur in coastal freshwater systems, accompanied by increasing temperatures. Freshwater populations can thus become vulnerable to the interactive effect of salinity and temperature, framed within their tolerance limits and adaptation ability to environmental stress. Taking this into consideration, the present thesis aimed at addressing the complex interactions resulting from the challenge of these environmental stressors on freshwater cladoceran populations. First, the halotolerance of different Simocephalus vetulus genotypes from two freshwater and one brackish population (salinity 2.3) was explored. The goal was to determine whether there was a genetic component of salinity resistance. Clone acute sensitivity was comparable among populations. However, all brackish clones, except one, were more halotolerant than freshwater genotypes, in terms of survival time. Life history assays, carried out with extreme genotypes (from previous experiment) revealed no relationship between fitness and the original environmental context of genotypes. Also, these experiments showed that freshwater populations do have the potential to tolerate salinity increases. As such, we can conclude that the local selective pressure caused by salinity was weaker than expected. Second, the acclimation ability of Daphnia galeata to salinity and temperature was investigated in this study, by evaluating Daphnia’s sensitivity to salinity, at two different temperatures, along a multigenerational acclimation scenario. The objective was to understand whether pre-adaptation to environmental stress (20ºC and 25ºC versus 0 g/L and 1 g/L of added NaCl) influenced the response to the latter exposure to these stressors. A tendency towards the increase of sensitivity to NaCl was observed, at higher temperature. However, this temperature-dependent effect was nullified after nine generations, but only when animals had been acclimated to both stressors (salinity and higher temperature). Third, we experimentally demonstrated that salinity interfered with inter-specific competition, altering the community composition of zooplankton communities. This body of evidence allowed us to reflect on the impacts of multiple stressors, particularly those related to climate change predictions. In parallel with experimental studies, within the framework of Education for Sustainable Development, it is also important to promote the development of the necessary competences towards the comprehension of global environmental change (e.g. the impact of salinity and temperature), in order to implement adequate mitigation and adaptation strategies. Hence, an activity with secondary school students was conducted, providing a good opportunity towards learning and competence acquisition in the interpretation of experimental data, as well as increasing awareness towards environmental issues.
Chaves, Marcelo Donizetti. « Estudo dos fatores ambientais associados a psoriase cutanea e lingua geografica ». [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289228.
Texte intégralDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A psoríase é uma doença cutânea crônica, cuja condição bucal mais freqüentemente associada é a língua geográfica. Aspectos como associação epidemiológica, lesões fundamentais e características microscópicas semelhantes, favorecem a idéia de que a língua geográfica seja a forma verdadeira da psoríase bucal. Este estudo foi realizado com o objetivo de identificar os fatores ambientais associados à psoríase cutânea e língua geográfica, bem como investigar suas interações. Os fatores ambientais avaliados foram etilismo, tabagismo, estresse emocional, cirurgias anteriores, atopia e erupções medicamentosas. Foram estudados 6.000 pacientes dermatológicos a partir dos prontuários de um ambulatório dermatológico, independente da idade, sexo e raça. A amostra foi constituída por 129 indivíduos com psoríase cutânea, 399 com língua geográfica e um grupo controle de 5472 indivíduos. Os pacientes portadores de psoríase, apresentavam ou não simultaneidade com língua geográfica, já os portadores de língua geográfica, não apresentavam psoríase. Realizou-se a análise estatística através do método qui-quadrado para a averiguação da associação dos fatores ambientais com a psoríase cutânea e língua geográfica. Os métodos coeficiente de Phi, coeficiente de contingência e V de Cramer, foram utilizados para a avaliação do grau das associações encontradas. A partir dos resultados obtidos pelas análises estatísticas, constatamos que: a) A prevalência do etilismo estava significativamente aumentada no grupo portador de psoríase em relação ao controle. O mesmo não foi observado no grupo portador de língua geográfica. b) O tabagismo apresentou uma associação negativa, embora fraca, com o grupo portador de língua geográfica. Quanto ao grupo de psoríase, não foi encontrada nenhuma associação estatisticamente significativa. c) As cirurgias anteriores mostraram associação significativa no grupo portador de psoríase, quando comparadas aos grupos controle e portador de língua geográfica. d) A atopia e as erupções medicamentosas não mostraram diferenças significativas. e) O estresse emocional foi o fator mais importante presente nos dois grupos de estudo, sendo substancialmente maior no grupo portador de psoríase em relação ao portador de língua geográfica. f) O estresse emocional e o etilismo em conjunto, apresentaram maior incidência nos grupos de estudo. g) o estresse emocional e o tabagismo em conjunto, mostraram o triplo da incidência no grupo portador de psoríase em relação ao portador de língua geográfica. h) A associação estresse emocional, etilismo e tabagismo foi 4 vezes maior no grupo com psoríase do que no controle. Esta associação não foi expressiva no grupo com língua geográfica. Estes dados nos permite concluir que as interações entre a psoríase e os fatores ambientais, difere das interações entre a língua geográfica e os mesmos fatores. Estas diferenças entre interações, podem ser responsáveis pela forma de manifestações diferentes desta condições, considerando serem ambas a mesma doença
Abstract: Psoriasis is a chronic cutaneous disease whose oral condition is more frequently associated to benign migratory glossitis. Aspects as epidemiological association, basic lesions and microscopic characteristics similarly support the idea that benign migratory glossitis is the true form of oral psoriasis. This study was done having the objective of identifying the environmental factors associated to cutaneous psoriasis and benign migratory glossitis, and to investigate their interactions. The regarded environmental factors were alcohol and tobacco consumption, emotional stress, past surgeries, atopy and drugs eruptions. 6.000 dermatological patients were studied from the records of the dermatological ambulatory, independently of age, gender or ethnic group. The sample was made up of 129 patients with cutaneous psoriasis, 399 with benign migratory glossitis and a control group of 5472 individuals. The patients suffering from cutaneous psoriasis presented benign migratory glossitis simultaneous or not, but the patients of the benign migratory glossitis group didn't present psoriasis. The statistical analysis through the method of qui-square for the verification of the association of the environmental factors with cutaneous psoriasis "and benign migratory glossitis was done. The methods of coefficient of Phi, contingency coefficient and V of Cramer were used for the evaluation of the degree of the found associations. From the results obtained by the statistical analysis, we verified that: a) The prevalence of the alcohol consumption was significantly increased in the patients of the psoriasis group in relation to the control. This was not observe in patients of the benign migratory glossitis group. b) Tobacco consumption presented a negative association, although weak, with the patients of the benign migratory glossitis group. As for the psoriasis group no statistically significant association was found. c) Past surgeries showed significant association in the patients of the psoriasis group, when compared to the control group and patients of the benign migratory glossitis group. d) Atopy and drugs eruptions didn't show significant differences. e) The emotional stress was the most important factor present in the two study groups, being substantially higher in the patients of the psoriasis group than to the patients of the benign migratory group. f) Emotional stress and alcoholism together presented higher incidence in the study groups. g) Emotional stress and tobacco consumption together showed three times more the incidence in patients of the psoriasis group in relation to patients of the benign migratory glossitis group. h) The association of the emotional stress, alcoholism and tobacco consumption was four times higher in the group with psoriasis than the control group. This association was not expressive in the group with benign migratory glossitis. These data allow the conclusion that the interactions between psoriasis and environmental factors differ from the interactions between benign migratory glossitis and environmental factors. These differences among interactions may be responsible for different forms of manifestations of these diseases, considering being both same disease
Mestrado
Estomatologia
Mestre em Estomatopatologia
Castro, Letícia Simões de. « Influências do enriquecimento ambiental no comportamento e nível de cortisol em felídeos silvestres ». reponame:Repositório Institucional da UnB, 2009. http://repositorio.unb.br/handle/10482/4816.
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O objetivo deste estudo foi avaliar as diferentes condições de cativeiro e seus efeitos no comportamento e fisiologia relacionados ao estresse em três espécies de felídeos pequenos: jaguatirica (Leopardus pardalis; n = 6), gato maracajá (Leopardus wiedii; n = 1) e gato-do-mato-pequeno (Leopardus tigrinus; n = 5). Os indivíduos estavam alojados em recintos individuais, e foram testados em três fases: Fase I – recinto vazio por 14 dias; Fase II – recinto enriquecido por 21 dias (diferentes tipos de enriquecimento foram utilizados ao mesmo tempo em cada recinto); Fase III – recinto vazio por nove dias. Amostras fecais foram coletadas semanalmente durante o estudo (de uma à três amostras) para análises de metabólitos de corticóides. Observações comportamentais foram realizadas durante aproximadamente 44h por cada indivíduo. A duração dos comportamentos relacionados a categoria de estresse foi significantemente menor (p ˂ 0,05) na fase II quando comparado com a fase I, principalmente os comportamentos pacing e coçar-se. Não houve diferença significativa dos níveis de corticóides entre as fases, mas diferenças inter-individuais foram detectadas. Ademais, os indivíduos interagiram mais com os enriquecimentos de vegetação e alimentar. Foram encontradas correlações significativas tanto positivas quanto negativas (p ˂ 0,05) entre os níveis de corticóides e alguns comportamentos relacionados a estresse. Os resultados indicam que os enriquecimentos em recintos de felídeos durante um curto período alteram o comportamento dos indivíduos, propiciando um aumento geral do bem-estar. Porém, uma mudança fisiológica necessitaria provavelmente uma exposição a enriquecimentos durante um período mais longo. __________________________________________________________________________________________ ABSTRACT
The main goal of this study was to evaluate the different captive conditions and their effect on the behaviour and physiology related to stress in three wild cats species, ocelot (Leopardus pardalis; n = 6), margay (Leopardus wiedii; n = 1) and tigrina (Leopardus tigrinus; n = 5). The individuals were housed as singleton, and they were tested in three phases: phase I – empty enclosure for 14 days; phase II – enriched enclosure for 21 days (different kinds of enrichment were used in the same time in every enclosure); phase III – empty enclosure for nine days. Faecal samples were collected weekly throughout the study (one or two samples) to analyse corticoid metabolites. About forty four hours of Behaviour observations were conducted on each individual. The duration of some behaviours related to stress, mainly pacing and self-directed scratching, was significantly shorter during the enrichment phase when compared to phase I (p<0.05). The levels of corticoid metabolites did not vary significative among phases, but inter-individual differences were detected. The individuals interacted more with vegetation and feeding enrichments than with others. The corticoid metabolites level was correlated with some stress behaviours. Overall results show that a short period of enrichment can alter the behaviour of enclosed wild cats, indicating enhanced welfare. However, a long-term physiological change would probably need a longer exposure to an enriched environment.
Serrano, Cánovas Raquel. « Mecanismos de adaptación de Saccharomyces cerevisiae a la alcalinización ambiental ». Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/3555.
Texte intégralEn primer lugar, partiendo de la identificación de ENA1 y PHO89 como genes regulados por pH alcalino cuya expresión es dependiente de calcineurina hemos establecido una relación entre la respuesta a pH alcalino y la vía de señalización de calcio/calcineurina. Demostramos que la alcalinización extracelular estimula el transporte de calcio desde el exterior dando lugar a un incremento en los niveles citoplasmáticos de este catión. Esta señal es la que desencadena la activación de la fosfatasa calcineurina, cuya acción principal, aunque no la única, es activar la expresión de una serie de genes implicados en la resistencia a pH alcalino.
Por otro lado, los resultados de microarrays indican que el estrés alcalino induce la transcripción de varios de los genes implicados en la obtención de fosfato y en el metabolismo de hierro y cobre. A su vez, el análisis de mutantes revela que tanto la integridad de elementos del regulón PHO como la del transporte de metales es esencial para la supervivencia en medio alcalino. Todo ello sugiere que la alcalinización medioambiental genera una situación de escasez de estos iones.
Asimismo hemos demostrado que la alcalinización extracelular provoca un incremento intracelular de ROS (o especies reactivas de oxígeno), lo que genera una situación de estrés oxidativo capaz de activar un conjunto de genes a través de los mecanismos específicos de respuesta a estrés oxidativo.
Por último, hemos descubierto una implicación de la vía de la integridad de la pared celular (CWI) en la respuesta a estrés alcalino. Hemos descrito que la ausencia de varios elementos implicados en dicha vía, como el sensor Wsc1 o las quinasas Bck1 y Slt2, da lugar a un fenotipo de sensibilidad a pH alcalino. Además, confirmamos que este estrés provoca la activación de Slt2, la MAPK de la vía CWI, y que el sensor de la vía más relevante en dicha activación es Wsc1. Por otro lado, el estudio de la respuesta transcripcional a pH alcalino de un mutante slt2 sugiere que esta quinasa es responsable de una parte de la respuesta transcripcional y que, probablemente, la alcalinización extracelular tiene efectos sobre la estructura de glucanos de la pared celular.
La conclusión final que se extrae de todos nuestros resultados es que la alcalinización medioambiental da lugar a una respuesta adaptativa que no es el resultado de la activación de una única vía de señalización específica para pH alcalino, sino que es el producto de activar diversas vías encaminadas a paliar las variadas alteraciones producidas por el estrés alcalino.
In this work we have studied the response to alkaline stress in the yeast Saccharomyces cerevisiae. To this end we have used mainly two high throughput analysis tools. First, we have performed an exhaustive analysis of the transcriptional response of this yeast to this kind of stress. In addition, we have used a mutant library, composed of more than 4800 mutants, in order to identify genes whose lack cause a growth defect in alkaline conditions.
First we have identified ENA1 and PHO89 as two genes overexpressed under alkaline conditions whose response to this stress was partially or totally dependent, respectively, on the phosphatase calcineurin. This represents the first evidence about the existence of a relationship between the alkaline response and the calcium/calcineurin signaling pathway. Further analyses have also demonstrated that extracellular alkalinization stimulates the import of calcium from the medium provoking a rise in the intracellular levels of this cation. This increment of calcium activates the calcineurin which functions, at least in part, promoting the expression of a set of genes involved in the tolerance to alkali.
In addition, the microarray data has shown that the alkaline stress induces the transcription of some of the genes involved in the phosphate uptake and in iron and copper metabolism. Besides, mutant analysis has revealed that the integrity of elements of the regulon PHO and that proper system to transport the mentioned metals are essential for the survival under alkaline conditions. Taken together, these evidences suggest that alkalinization of the environment leads to a situation of starvation of these anions.
We also have demonstrated that alkaline pH increments intracellular ROS (reactive oxygen species) that, in turn, cause an oxidative stress situation that activates the transcription of a subset of genes involved in the defense to oxidation.
Finally, we have reported a relationship between the cell wall integrity (CWI) pathway and the alkaline response. Cells lacking some proteins previously related to this pathway, such as the Wsc1 sensor or the Bck1 and the Slt2 kinases, are hypersensitive to alkaline stress. We also have confirm that alkaline stress causes the activation of Slt2, the MAPK of the CWI pathway, and that Wsc1 is the major sensor involved in this activation. In addition, a study of the transcriptional response to alkali in a slt2 mutant has shown that this kinase is involved in the global transcriptional response to alkaline stress.
The final conclusion that can be extracted from all the data presented here is that the alkalinization of the ambient triggers an adaptive response that results from the activation of multiple cellular pathways.
Malavasi, Stefano. « Ecologia riproduttiva di gobidi lagunari e sue possibili applicazioni al rilevamento di stress ambientale ». Doctoral thesis, Università Ca' Foscari Venezia, 2002. http://hdl.handle.net/10579/210.
Texte intégralMillach, Carrobé Laia. « Effect of environmental changes and metal stress on phototrophic microorganisms in extree environments. Development of new methodologies in high-resolution microscopy techniques ». Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/457901.
Texte intégralLos efectos del cambio climático inciden directamente en las poblaciones de microorganismos fototróficos de los tapices microbianos, produciendo alteraciones en otros parámetros ambientales como es el incremento de la temperatura, que puede provocar sequías y hasta la desertización de estos ecosistemas, así como otros efectos en la osmolaridad de las células, debido al aumento de la salinidad. Dichos microorganismos son muy abundantes en los tapices microbianos, principalmente las cianobacterias y las microalgas, que además de ser los principales estabilizadores de estos ecosistemas, a veces se encuentran expuestos a diferentes condiciones de estrés. La mayoría de los estudios, que se realizan para valorar los efectos que tienen sobre los microorganismos condiciones ambientales tan variables, utilizan cultivos axénicos que provienen de microorganismos aislados del ambiente natural o bien de colecciones de cultivos; nada más lejos de la realidad, ya que en los ambientes naturales los microorganismos fototróficos establecen asociaciones estables con microorganismos heterotróficos y, a veces, con otros fototróficos. Además, hay pocos estudios que analicen, en estas condiciones y a nivel individual, los efectos de los parámetros ambientales o de la contaminación por metales en estas asociaciones. La falta de metodologías que pueden aplicarse para averiguar estos efectos en un microorganismo en concreto, cuando está asociado con otro de manera selectiva, in vivo, de manera rápida y sin el uso de ningún tipo de tinción, es, por tanto, un reto a la hora de analizar las posibilidades que tienen estos microorganismos frente a cambios tan drásticos. En este trabajo, se ha intentado solucionar dicha problemática mediante la optimización de distintas técnicas que tienen como base el microscopio láser confocal, considerando la característica principal de las cianobacterias y las microalgas, que es la de emitir fluorescencia natural. La clorofila a es el pigmento mayoritario de estos microorganismos y se ha utilizado con anterioridad como bioindicador, especialmente en estudios realizados en metales por otros miembros del grupo. Asimismo, una problemática importante es valorar el papel que juegan estos microorganismos en la resistencia ante cambios repentinos de las condiciones naturales o antropogénicas. En este sentido, también se ha incrementado el interés por las denominadas células durmientes y en el estudio de células viables y no viables. Por este motivo, en este trabajo se ha puesto a punto una nueva metodología que utiliza el microscopio láser confocal y dos láseres específicos y que ha permitido determinar el porcentaje de estas células en muestras expuestas a diferentes condiciones de estrés. Los microscopios electrónicos de rastreo y transmisión, ambos acoplados a un detector de energía dispersiva de rayos X, junto con el microscopio de transmisión de rayos X del sincrotrón ALBA, se han aplicado en muestras expuestas a varios factores de estrés para evaluar los cambios morfológicos en células enteras y en secciones ultrafinas, así como para los estudios de captación de metales extra- e intracelularmente. Los objetivos de este trabajo se han centrado en la aplicación combinada de todas estas metodologías en dos consorcios de microorganismos: Scenedesmus sp. DE2009 y Geitlerinema sp. DE2011. El efecto de la luz y la salinidad (como parámetros ambientales), así como el impacto de metales como plomo, cobre y cromo (como contaminantes), se ha estudiado ampliamente en células individuales de ambos microorganismos. Finalmente, esta tesis está estructurada en distintos capítulos. El Capítulo 3 corresponde con los artículos publicados (uno de ellos en revisión); así pues, los resultados obtenidos de las investigaciones realizadas se exponen en las Secciones 3.1, 3.2 y 3.3 y se discuten globalmente en el Capítulo 4.
The effects of climate change directly affect the populations of phototrophic microorganisms in microbial mats, causing alterations in other environmental parameters such as the increase in temperature. This in turn causes drought and sometimes the desertification of these ecosystems, as well as affecting the osmolarity of cells due to the increase in salinity. The microorganisms referred to are highly abundant in microbial mats; principally, they are cyanobacteria and microalgae, which, apart from being the main stabilisers of these ecosystems, are exposed to distinct stress conditions at the same time. Most studies carried out to assess the impact on microorganisms of such variable environmental conditions use axenic cultures that come from microorganisms isolated from the natural environment or else from culture collections. Nothing could be further from reality, since—in natural environments—phototrophic microorganisms establish stable associations with heterotrophic bacteria and, at times, with other phototrophs. In addition, very few studies analyse (in these conditions and at individual level) the effects of environmental parameters or of metal pollution in these associations. The lack of methodologies that can be applied to ascertain these effects in a specific microorganism, when this is selectively associated with another, in vivo, swiftly and without using any type of staining, is therefore a challenge in analysing the possibilities of these microorganisms when facing such drastic changes. In the current work, an attempt has been made to solve this problem by means of the optimisation of distinct techniques, based on confocal laser microscopy and centring on the main characteristic of cyanobacteria and microalgae, which is the emission of natural fluorescence. Chlorophyll a is the majority pigment in these microorganisms and has previously been used as a bioindicator, in studies carried out with metals by other members of the group. Determining the role played by these microorganisms in the resistance to sudden changes in natural or anthropogenic conditions is a further, and important, issue. In addition, in this respect, the interest in dormant cells and in the study of viable and non-viable cells has increased. For this reason, a new methodology has been developed in this work; using a confocal laser microscope and two specific lasers, this has allowed us to ascertain the percentage of these cells in samples exposed to distinct stress conditions. The electronic scanning and transmission microscopes, both coupled to an X-ray dispersive energy detector, jointly with the X-ray transmission microscope from the ALBA synchrotron, have been used in samples prepared to evaluate morphological changes due to stress factors both in complete cells and in ultrafine sections, as well as in studies of extra- and intracellular metal extraction. The objectives of this work centre on the combined application of all these methodologies on two consortia of microorganisms: Scenedesmus sp. DE2009 and Geitlerinema sp. DE2011. The effect of light and salinity (as environmental parameters), in addition to the impact of lead, copper and chromium (as pollutants) was studied extensively in individual cells for both microorganisms. Finally, this thesis is organised into distinct chapters. The Chapter 3 correspond to the articles that have already been published (one of them currently under review); thus, the results obtained from the research carried out are therefore presented in Sections 3.1, 3.2 and 3.3 and are discussed globally in Chapter 4.
Labrador, Laura Gonçalves. « Enriquecimento ambiental em cães de abrigo - uma abordagem ao comportamento e à fisiologia ». Master's thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/28736.
Texte intégralColas-Rosas, Paul François. « Estresse nos morcegos Artibeus obscurus e Artibeus fimbriatus (Chiroptera, Phyllostomidae) como resposta à perturbação ambiental / ». Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/99511.
Texte intégralAbstract: The stress response plays a physiological key role by allowing the organisms to cope and survive to situations of risks for your internal balance. However, the chronic activation of the stress response, as the one triggered by environmental disturbances, can result in several deleterious effects to the organisms, which may reduce the fitness and jeopardize the maintenance of populations of sensitive species. We investigated the effect of the environmental disturbance on the bats Artibeus obscurus and Artibeus fimbriatus in the Atlantic forest of Brazil. Ecological and physiological indicators were used to compare the sensitivity to environmental changes, body condition, and stress response between populations in an undisturbed and a disturbed area. The ecological index of sensitivity to changes, based on measures of population abundances, suggests that A. obscurus is more tolerant to environmental modifications than A. fimbriatus (34% and 76%, respectively). The body condition indexes (IC) of A. obscurus were similar between areas, whereas the IC of A. fimbriatus was smaller in the disturbed area compared to the undisturbed. Additionally, levels of basal and stress-induced circulating cortisol of A. obscurus did not differ between the two areas, whereas the hormonal levels of A. fimbriatus were markedly different, for instance presenting a baseline cortisol level 52% higher in the disturbed area. Possibly, the tolerance to environmental changes observed in A. obscurus is due to its higher habituation ability which prevents the species to suffer from the deleterious consequences of the chronic stress. On the other hand, the failure of habituation of A. fimbriatus to disturbed environments can lead to physiological disorders, as expressed by decrease the body condition index.
Orientador: Ariovaldo Pereira da Cruz Neto
Coorientador: José Eduardo de Carvalho
Banca: Fernando Ribeiro Gomes
Banca: Marco Aurélio Ribeiro Mello
Mestre
Cintra, Lílian de Moura Borges. « CONTEXTO AMBIENTAL E PROFISSIONAL DO CANTOR DA NOITE ». Pontifícia Universidade Católica de Goiás, 2011. http://localhost:8080/tede/handle/tede/2886.
Texte intégralThe aim of this study was to understand how singers experience the impact of their work environment on their voice and their well being. Semi structured interviews were conducted with 30 professional singers in Goiânia, 15 of them women and 15 men, all between 21 and 49 years of age. A grounded theory analysis was made of the interviews. Four categories were constructed: (1) Stressful environment, marked by contextual and situational stress; (2) Risk factors including undisciplined use of the voice and giving in to the demands of the labor market; (3) Coping, meaning how the singers dealt with stress and blunt its effects; (4) Factors of protection including professional relationships and personal characteristics of the singer. The sources of stress and the risk factors was present both in the broad context of professional activity and in the direct environment when the show takes place. But coping strategies and protective factors could make an immense difference. Lack of care for the voice can be understood in the context of the demands of the labor market and financial pressure. Finally, the profession s social environment can also offer protection against the risks and the damaging effects of stress. As far as the singers have knowledge of their vulnerabilities, they can develop more adequate coping strategies, improve their vocal performance and advance their interpersonal relations with other professionals to build a protective social network.
O objetivo da pesquisa foi verificar como o cantor vivencia a interferência do ambiente de trabalho em sua voz e em seu bem-estar. Foram realizadas trinta entrevistas semiestruturadas com cantores que atuam profissionalmente em Goiânia/GO, sendo quinze homens e quinze mulheres com idade entre 21 e 49 anos. Uma análise norteada pelos princípios da Grounded Theory foi aplicada a essas entrevistas, tendo sido construídas quatro categorias: (1) Ambiente estressante caracterizado por estresse contextual e situacional; (2) Fatores de risco, incluindo a indisciplina com a voz e o ceder às exigências do mercado; (3) Coping descrevendo o que os cantores fazem para lidar com o estresse e amenizar seus efeitos; (4) Fatores de proteção, incluindo as relações profissionais e as características pessoais do cantor. As fontes de estresse e os fatores de risco estavam presentes tanto no contexto amplo da profissão quanto no ambiente direto do show, mas vale ressaltar que as estratégias de coping e os fatores de proteção podem fazer muita diferença. O descuido pode ser entendido devido ao contexto das exigências do mercado e a pressão financeira. Finalmente, o ambiente social da profissão também pode oferecer proteção contra os riscos e os efeitos prejudiciais do estresse. À medida que os cantores têm conhecimento das suas limitações podem desenvolver estratégias de coping mais adequadas, melhorando, inclusive, o seu desempenho vocal e as relações interpessoais com outros profissionais, assim como sua proteção pela rede social.
SANTO, ANDREA. « Seed germination requirements and salt stress tolerance of coastal rare species in Sardinia ». Doctoral thesis, Università degli Studi di Cagliari, 2013. http://hdl.handle.net/11584/266220.
Texte intégralArroyo, Sánchez Laura. « Estudio neurofisilógico del estrés y el enriquecimiento ambiental en ganado porcino ». Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/458133.
Texte intégralModern pig husbandry, focused on reducing costs and increasing productivity, has led to a loss of animal welfare. There are multiple factors known to cause stress and/or loss of welfare in porcine production, such as food restriction, adverse environmental conditions and management. Legislation has advanced in recent years to establish breeding, housing, transport and slaughter conditions that guarantee acceptable animal welfare. Classical methodologies for measuring stress and animal welfare are behavioral observations and serum biomarkers that are altered in the stress response. These techniques have limitations, and they are not objective and specific enough to assess stress. On the other hand, it is not known how the brain neurochemical pattern of response to stress is altered. Unravel these variations would be the paradigm for the characterization of this response. Therefore, in this work, besides evaluating the traditional markers in the serum under different housing conditions, stress and/or pig characteristics, neurotransmitters and other parameters in the central nervous system (CNS) are evaluated. Neural pathways that control the response to stress, fear, aggression, emotion, and other behaviors include specific brain regions such as the amygdala, hippocampus or prefrontal cortex, which process information from external and internal stimuli, and organize the autonomous response by regulation of the hypothalamic-pituitary-adrenal axis. This work consists of 4 chapters analyzing different possible stressors: susceptibility to stress caused by the halothane genotype, combined with different sex; management stress, combined with response to fear; transport stress combined with indoor/outdoor housing and enriched housing conditions. Differences observed in serum biomarkers caused by these conditions are very variable, but some variations in their levels may be associated with the different conditions of breeding, slaughter and characteristics of the animals. Traditionally the noradrenergic system has been related to the stress response, but the dopaminergic and serotonergic systems are also consistently involved. Mild alterations of the serotonergic pathway are related to management stress and a fearful phenotype to external stimuli. On the other hand, long transport stress activates the mesocorticolimbic and noradrenergic dopaminergic pathways towards the prefrontal cortex. Analysis of other molecular markers of stress, such as the neurotrophic factor BDNF, c-Fos and ERK1/2 also suggest this effect of transport stress on neural networks. Outdoor housing does not confer great changes in the neurotransmitter pathways, but suggests a different capacity to cope with transport stress; and barren housing conditions causes the activation of the dopaminergic and noradrenergic pathways in several corticolimbic regions. Proteomic tools were used to determine the differential expression of proteins in the hippocampus between two different housing conditions (enriched and barren), suggesting changes in neuronal activity. In synergy with what is observed at neurotransmitter levels, a direct effect of housing conditions on CNS regions involved in emotion and stress management is suggested. All these results suggest the specificity of the stress response according to the individual trait, the type and the intensity of the stressor, and the effect of the housing conditions on the CNS, indicating the need to continue improving the conditions of breeding, transport and slaughter of farm animals to ensure the highest welfare and least stress. Also, it is necessary to improve the understanding of the laboratory evaluation and the molecular basis of these processes.
Estevam, Francisca Nivanda de Lima. « Variáveis ambientais e ergonômicas na operação com microtrator ». reponame:Repositório Institucional da UFC, 2015. http://www.repositorio.ufc.br/handle/riufc/20220.
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The use of microtratores in family farming optimized the work, but still, did not exclude the operator of the activity of risk, because it gets the job done in fully exposed open field the variation in climatic conditions, especially solar radiation, temperature and humidity relative, apart from the loud noise and vibration produced by microtractor. The characterization of environmental and occupational hazards produced by the machine are needed for the development of strategies that can minimize risk and provide conditions for the operator to perform their activities without compromising their condition. The study was conducted at the Experimental Farm Crop Drought (FELS) of the Federal University of Ceará (UFC) in the municipality of Quixadá, central backwoods of Ceará. We used a microtractor model TC14 Super (motor cultivator) brand Yanmar Agritech, coupled to a rotary tiller. For measurements of climate variables, operator and microtractor were used sensors and devices installed in them. The experiment was done factorial 3x5, which were used three speeds to five times throughout the day. The data were submitted to variance analysis and the averages were compared by Tukey test at 5% probability. It was concluded that the activity carried out by microtractor operator in the city of Quixadá-Ceará is considered stressful, due to the high thermal load and municipal climate feature. All methods used were of value to characterize the activity that proved unhealthy for noise and vibration for wholesome. The OWAS (Ovako Working Posture Analysing System) method was effective to identify ergonomic risk of the activity, and operator's back part of the most affected body, the operator's tendency to tilt during activity, it is recommended to implement fitness labor, stretches before and after activity to reduce the risk of muscle injury and back pain.
A utilização de microtratores na agricultura familiar otimizou o trabalho, mas ainda assim, não excluiu totalmente o operador dos riscos da atividade, pois o mesmo realiza o trabalho em campo aberto totalmente exposto a variação das condições climáticas, principalmente a radiação solar, temperatura e umidade relativa, além do ruído intenso e da vibração produzida pelo microtrator. A caracterização deste ambiente e dos riscos laborais produzidos pela máquina são necessários para o desenvolvimento de estratégias que possam minimizar os riscos e dar condições ao operador de desempenhar sua atividade sem comprometimento da sua condição física. O trabalho foi realizado na Fazenda Experimental Lavoura Seca (FELS) da Universidade Federal do Ceará (UFC) localizada no município de Quixadá, sertão central do Ceará. Utilizou-se um microtrator modelo TC14 Super (cultivador motorizado), marca Yanmar Agritech, acoplado a uma enxada rotativa. Para as medições das variáveis climáticas, do operador e do microtrator foram utilizados sensores e aparelhos instalados nos mesmos. O delineamento experimental foi feito esquema fatorial 3x5, onde foram utilizadas três velocidades para cinco horários ao longo do dia. Os dados obtidos foram submetidos à análise de variância, sendo as médias comparadas pelo teste de Tukey a 5% de probabilidade. Concluiu-se que a atividade realizada pelo operador de microtrator no município de Quixadá-Ceará é considerada estressante, devido à alta carga térmica e característica do clima do município. Todos os métodos utilizados foram de valia para caracterização da atividade que se mostrou insalubre para o ruído e salubre para vibração. O método OWAS (Ovako Working Posture Analysing System) foi eficaz para identificar o risco ergonômico da atividade, sendo as costas do operador a parte do corpo mais afetada, pela tendência do operador de se inclinar durante a atividade, recomenda-se a implementação de ginástica laboral, alongamentos antes e depois da atividade, para diminuir o risco de lesões musculares e lombalgias.
Daniel, Sofia Alexandra António. « Estudo sobre o impacto de uma estrutura de enriquecimento ambiental no comportamento do lince ibérico (Lynx pardinus, themmink 1824) em cativeiro ». Master's thesis, Universidade de Évora, 2018. http://hdl.handle.net/10174/23362.
Texte intégralROSSI, Miriam. « Analysis of poplar plants responses to environmental stress conditions ». Doctoral thesis, Università degli studi del Molise, 2017. http://hdl.handle.net/11695/79757.
Texte intégralIn the recent years, the issues of environmental changes received a well-justified attention from scientists and policy makers especially because several dramatic alterations have been recorded at ecosystem and species distribution level (Aber et al., 2001; Loreau et al., 2001). According to literature, global climate changes (Walther et al., 2002) and environmental pollution (Islam et al., 2004) are widely recognized as the most important causes of environmental alterations. In fact, it has been shown that environmental contamination by pollutants induces several diseases on plants, animals and human, representing with climate change, the most important cause of species extinction (Leduc et al., 2004). Often environmental changes become, for plants “stress conditions” (i.e. drought, salinity, extreme temperatures, pollutants or mechanical stress; Boyer, 1982). To forefront adverse conditions, plants have developed different adaptive strategies (Boyer, 1982; Nilsen and Orcutt et al., 1996; Borics et al., 2013) that include morphological, physiological, biochemical and molecular adjustments. Mechanisms that allow plants to withstand environmental stress has become an interesting field of scientific research. In fact, understanding how plants respond to stress conditions could be useful not only for plant biology advances, but also for improving the efficiency of strategies based on the use of plants for environmental changes mitigation (Mbow et al., 2014). This thesis presents a PhD research that focalized the attention on the molecular mechanism that allow woody perennial plants to forefront environmental changes, with a particular focus on mechanical and heavy metal stress. The first part of this thesis provides new insight about the complex and almost unknown molecular mechanisms regulating woody root responses to mechanical stress, that represents a really common environmental perturbation that considerably affect plant stability. By using a simple experimental system, a controlled simulation of mechanical stimuli was performed in Populus nigra roots. After analyzing the proteomic alteration and the involvement of auxin in poplar woody root subjected to bending stress, the attention was focalized on the role of miRNAs (microRNA) in regulating mechanical stress responses. By using a reverse transcription-quantitative PCR (RT-qPCR) approach, the study evaluated the expression level of five mechanically-induced miRNAs (ptc-miR162, ptc-miR164, ptc-miR172, ptc-miR408, ptc-miR473), previously identified in bent poplar stem by Lu et al., (2005). Moreover, the study provides the analysis of miRNAs cis-regulatory promoter elements and the computationally and experimentally prediction of miRNA target genes. A highly complex miRNAs expression pattern was recorded in poplars roots subjected to bending stress, showing that their expression is not only regulated by tension and compression forces (Trupiano et al., 2012 a, b), but also by other important process related to bending stress responses such as lateral root formation and lignin deposition. Since “rhizoremediation” represents a great challenge to phytoremediation purpose (Glick, 2003). Last part of the studies carried out in this thesis, were focused on plant-microbes interactions to remove heavy metal in polluted sites. Preliminary results are reported in this thesis where a strain belonging to Bacillus genus was isolated from a lead (Pb) and arsenic (As) polluted soil. This isolated strain showed the great capability to tolerate Pb and As exposure, and can be further used in association with several plants species for rhizoremediation purposes. In conclusion, results on molecular mechanisms involved in root response to mechanical stress, and the data on heavy metal bacteria strains although preliminar, provided by this thesis, contribute to widen the knowledge on the use of plants for environmental changes mitigation.
Nascimento, Davi Roncoletta. « Respostas de CAM às variações ambientais na bromélia Dyckia tuberosa (Vellozo) Beer ». Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-21012013-143339/.
Texte intégralPlants with crassulacean acid metabolism are able to support conditions of low availability of water through a carbon dioxide concentration system which increases the efficiency of use of water through an overnight CO2 fixture under low deficit of vapor pressure between the leaf and the atmosphere. This process favors the occupation of arid regions and places where water can quickly become unavailable. The occurrence of this type photosynthetic covers a wide range of taxa, including the Bromeliaceae family. Among the species of Bromeliaceae presenting CAM is Dickya tuberose, a species that has a great abundance on rocky outcrops associated with natural monument of Pedra Grande - Atibaia - SP. At this site, D. tuberose has a role in vegetation associated with surface rock exposed as an essential component of communities called \"vegetation islands\". The conditions prevailing in the rocky outcrop of Pedra Grande are of great scarcity of land and water, and extreme exposure. The variations in water availability in rocky outcrop would be due, among other reasons, the size of the islands where vegetation D. tuberose occurs and the characteristics of inclination and orientation of the slope of the rocky surface where the island is installed. From the observations in the natural environment, wonders whether the patterns of assimilation in D. tuberose related to CAM presents variations associated characteristics of vegetation islands where it occurs. To investigate this relationship, plants of D. tuberose were studied in field and semi-controlled conditions in a greenhouse. The technique used to characterize patterns of CAM was the titration acidity of the mesophyll. In both experimental groups undergoing different periods of suspension of irrigation as in samples obtained directly from the field, there are patterns of variation in acidity that may be associated with variations in water supply. The changes were characterized by the difference in acidity between the early morning and late afternoon. The reduction in amplitude of the variation coincided with the intensity of the restriction in water supply. However, the variation was associated with reduced acidity value at the end of the day, which would be associated with a reduction in the recapture of CO2 during the illumination period. The major influence detected on plants in the field was the relative humidity. It is conjectured a part of the assimilation of water through the leaves of D. tuberose as an essential attribute of the occupation of substrate in Pedra Grande - Atibaia
Preto, Vivian Aline. « O estresse em universitários de enfermagem e sua relação com fatores pessoais e ambientais ». Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/22/22131/tde-31082018-155141/.
Texte intégralIn light of the evidence that stress is present among university nursing students and the evils that chronic stress can cause to physical and mental health, this study was aimed at assessing the influence of personal and environmental factors related to the recent stress in university nursing students, as well as to assess the occurrence, the associated factors and the predictors of the recent stress. We performed an epidemiological, cross- sectional and analytical study, with a quantitative approach, in two private higher education institutions, with 209 nursing students from the first to the last year. Regarding the data collection tools, we used a sociodemographic questionnaire about occupational and health conditions, the -Childhood Trauma Questionnaire? (CTQ), the Perceived Stress Scale (PSS), the -Inventory of Symptoms of Stress? for adults (ISSL), the -Rosenberg Self-Esteem Scale? and the -Holmes-Rahe Social Readjustment Scale?. In order to analyze the data, we used descriptive statistics, measures of central tendency, Pearson Chi-square test (?²) or Fisher exact test, when the mathematical assumptions for the Chi-square test were violated, and binary logistic regression, using the SPSS software, version 21. The level of significance adopted throughout the analysis was 5% (alpha = 0.05). We have observed that, among university nursing students, 164 (78.5%) presented stress, and most in the resistance stage, 121 (57.9%), especially with manifestations of psychological symptoms, 121 (57.9%); 77 (36.8%) experienced early stress, with a predominance of emotional abuse, 42 (20.5%); and 40 (20%) present strong chances of becoming ill. Most of them have medium or high self-esteem, 106 (50.7%) and 95 (45.5%), respectively. The recent stress was associated with health problems, use of medication, selfreport of stress, perception of stress, and demands for social readjustment. Moreover, performing physical activity, smoking, high self-esteem, experiences of early stress and having religion were signalized as predictors of stress. Conversely, medium and high perceived stress, being married, working, working in the health area and having weekly leisure activities represent lower chances of suffering from stress in the surveyed university nursing students. We have concluded that personal factors such as health problems, use of medication, self-report of stress, perception of stress and the environmental factor demands for social readjustment influence on the recent stress in university nursing students
Colas-Rosas, Paul François [UNESP]. « Estresse nos morcegos Artibeus obscurus e Artibeus fimbriatus (Chiroptera, Phyllostomidae) como resposta à perturbação ambiental ». Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/99511.
Texte intégralConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A resposta ao estresse tem uma importante função auxiliadora que permite que os organismos lidem e sobrevivam a ameaças ao seu equilíbrio interno. Entretanto, a ativação crônica da resposta ao estresse, como a causada pela perturbação do ambiente, pode acarretar em diversos efeitos deletérios diminuindo a aptidão dos indivíduos e colocando em risco populações locais das espécies. Investigamos o efeito da perturbação ambiental sobre os morcegos Artibeus obscurus e Artibeus fimbriatus de uma área preservada e de uma área perturbada de Mata Atlântica do Brasil. Indicadores ecológicos e fisiológicos foram utilizados para se verificar a sensibilidade à modificação ambiental, condição corpórea, e a resposta ao estresse entre populações das duas áreas. O índice ecológico de sensibilidade à perturbação, baseado em medidas de abundância, sugere que A. obscurus é mais tolerante a modificações ambientais do que A. fimbriatus (34% e 76%, respectivamente). As análises de índice de condição corpórea (IC) demonstraram que A. obscurus não demonstrou mudança na condição corpórea entre áreas enquanto A. fimbriatus apresentou menores valores de IC na área perturbada do que na preservada. Adicionalmente, os níveis de base e de estresse-induzido do hormônio indicador de estresse (cortisol) não diferiram entre áreas para A. obscurus enquanto que uma marcada diferença foi observada para A. fimbriatus que apresentou níveis de base aproximadamente 52% maiores na área perturbada. Possivelmente, a maior tolerância a perturbação ambiental observada para A. obscurus seja decorrente da capacidade que esta espécie possui em habituar-se hormonalmente ao ambiente perturbado e evitar as conseqüências deletérias do estresse crônico. Por outro lado, a incapacidade de habituação de A. fimbriatus ao ambiente perturbado pode estar ocasionando debilitações...
The stress response plays a physiological key role by allowing the organisms to cope and survive to situations of risks for your internal balance. However, the chronic activation of the stress response, as the one triggered by environmental disturbances, can result in several deleterious effects to the organisms, which may reduce the fitness and jeopardize the maintenance of populations of sensitive species. We investigated the effect of the environmental disturbance on the bats Artibeus obscurus and Artibeus fimbriatus in the Atlantic forest of Brazil. Ecological and physiological indicators were used to compare the sensitivity to environmental changes, body condition, and stress response between populations in an undisturbed and a disturbed area. The ecological index of sensitivity to changes, based on measures of population abundances, suggests that A. obscurus is more tolerant to environmental modifications than A. fimbriatus (34% and 76%, respectively). The body condition indexes (IC) of A. obscurus were similar between areas, whereas the IC of A. fimbriatus was smaller in the disturbed area compared to the undisturbed. Additionally, levels of basal and stress-induced circulating cortisol of A. obscurus did not differ between the two areas, whereas the hormonal levels of A. fimbriatus were markedly different, for instance presenting a baseline cortisol level 52% higher in the disturbed area. Possibly, the tolerance to environmental changes observed in A. obscurus is due to its higher habituation ability which prevents the species to suffer from the deleterious consequences of the chronic stress. On the other hand, the failure of habituation of A. fimbriatus to disturbed environments can lead to physiological disorders, as expressed by decrease the body condition index.
DE, ZIO Elena. « The responses of poplar plants to mechanical bending stress ». Doctoral thesis, Università degli studi del Molise, 2017. http://hdl.handle.net/11695/82358.
Texte intégralMechanical stress is a common environmental perturbation that can considerably affect plant stability. In the course of evolution, plants evolved different mechanisms for coping with and mitigating the negative effects of this disadvantageous abiotic stress. Study the impact of this stress on the woody plant means to provide a scientific basis in the knowledge of the root biology and complex dynamics of the reaction wood formation, important in the context of plant productivity and utilization. In this thesis, a controlled simulation of mechanical stress was performed in Populus nigra roots by using a simple experimental system. After giving an outline of the molecular mechanisms that regulate the responses to long-term bending stress between the two sides of the poplar root (the convex and the concave side), this thesis lays emphasis on the roles of main plant hormones in the stress-induced reaction wood formation. Using the method based on liquid chromatography coupled to tandem mass spectrometry analysis (LC-MS/MS) auxins, abscisic acid and cytokinins profiling was obtained for different sectors and sides of the bent root and stem, subjected to different intensities of tension and compression forces. Data obtained were then compared in order to verify similarities and differences between root and stem response to bending. In order to better understand the role of hormones in the induction of cambial zone of poplar root subjected to bending, a method for isolation of cambial tissue was developed and the analysis of auxins, abscisic acid and cytokinins profile was carried out. Taking together, data of this thesis showed as poplar root responds to bending producing in the concave zone a compression wood, rich in lignin content, with features similar to the compression wood produced at stem level by gymnosperms. A high level of auxin and abscisic acid seems to accompany this development process, even in the early phases of the treatment.
Fernandes, Célia Carolina Moreira. « H. portulacoides and J. maritimus in a mercury contaminated salt marsh : metal accumulation, biochemical and lipidomic patterns ». Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22320.
Texte intégralThe salt marshes, one of the most productive ecosystems, serves as the sink for contaminants, namely metals from industries, reducing in this way the contamination of surrounding ecosystems. Although, as levels of contaminants, the ability of salt marshes to incorporate wastes can be impaired. In the aquatic environment, high mercury (Hg) pollution is mainly due to metal discharge of effluents from chloralki plants containing high concentrations of this metal. Mercury has been recognized as heavy metal and extremely toxic to plants interfering with several crucial cellular processes. This study evidenced the importance to understand the analysis that plants under environmental exposed to Hg and to evaluate impact of Hg toxicity in plants salt marsh communities. Better knowledge on these accumulation aspects will evaluate the stress imposed by Hg on primary production in salt marsh plants and adaptation of mobility of the metal in the ecosystem. As well as the molecular mechanisms mercury tolerance, which are important to clean efficiently Hg contaminated systems in order to an effective restoration is achieved. In this way, the work focused on two species of halophytes, Halimione portulacoides and Juncus maritimus collected at two sites of the Ria de Aveiro contaminated by mercury, considered s1 as less contaminated site and s2 as the most contaminated site. Thus, this work was designed to (1) evaluate how Hg distribution in plants would avoid high Hg concentrations (2) which way plants would retain Hg toxicity by triggering antioxidant responses. Indeed, most of biochemical parameters determinate the evidence of different responses by different concentration of Hg in the sediment (s1 and s2) and (3) plants can or not modify their lipid composition by Hg toxicity through the UPLC-MS methodology. This study demonstrated that both plant species restricted Hg uptake. However, the process was more efficient in H. portulacoides. Was observed differences in the amount of Hg accumulated by both species. Allocation patterns also differs between species. H. portulacoides showed different levels of Hg between leaves, stems and roots, while J. maritimus accumulated the higher levels of Hg in roots. The conjugation of both process, absorption and translocation resulted in similar Hg concentrations in stems and leaves and much higher Hg levels in J. maritimus roots. The results obtained demonstrate that Hg generated oxidative damage in the roots of both species and in leaves of H. portulacoides. Differences in LPO between species obtaining for each specie reflects not only the level of Hg accumulated and Hg distribution but also the ability to trigger the defense mechanisms. J. maritimus was able to increase the protein levels and DHAR activity in roots and rhizomes and GSTs in rhizomes. H. portulacoides was not able to induce the antioxidant enzymatic responses. Although in leaves antioxidant molecules such carotenoids and α-tocopherol were enhanced. In lipidome study, species also showed differences. In H. portulacoides, phospholipids decreased in all the organs analyzed, which can subject an alteration of membrane permeability. In addition, galactolipids decreased, reducing the efficiency on photosynthesis. However, α-tocopherol increased, and so better protection to chloroplast membranes and maintenance of photosynthetic activity provided. In J. maritimus, lipid changes were only detected in roots and rhizomes, increasing lipid permeability and explaining the higher bioaccumulation at high Hg concentrations. Phyto sterols decreased significantly in roots and lead to alterations of permeability membrane. α-tocopherol was detected in both organs of J. maritimus, a decrease that demonstrate an ineffective Hg contamination. This study may be a starting point for further work, namely in other marshes, in other species and with other metals. Understanding the mechanisms inherent to in heavy metal tolerance in marsh plants and the changes in lipid composition are important to detect the impact of metals in these ecosystems.
Os sapais, considerados um dos ecossistemas mais produtivos, servem como reservatório para contaminantes, nomeadamente metais provenientes de industrias, reduzindo desta forma a contaminação dos ecossistemas circundantes. Em ambiente aquático, a poluição por mercúrio (Hg) é principalmente devido a descargas de efluentes de industrias contendo concentrações elevadas deste metal. O mercúrio é reconhecido como sendo um metal pesado e extremamente tóxico para as plantas, interferindo desta forma em vários processos celulares cruciais. Este estudo evidenciou a importância de compreender o processo aquando da exposição das plantas ao mercúrio e desta forma avaliar o impacto da toxicidade do Hg nas comunidades de sapais. Uma melhor compreensão sobre estes aspetos de acumulação avaliará o stress imposto pelo Hg sobre a produção primária em plantas de sapal e a adaptação das plantas no ecossistema. Adicionalmente este estudo permite também a interpretação dos mecanismos moleculares da tolerância ao mercúrio das plantas uma vez que estas são importantes para uma limpeza eficiente dos sistemas contaminados por Hg para uma restauração efetiva. Desta forma, o trabalho incidiu em duas espécies de plantas halófitas, Halimione portulacoides e Juncus maritimus recolhidas em dois locais da Ria de Aveiro contaminados por mercúrio, s1 considerado como o local menos contaminado e s2 como o local mais contaminado. Este estudo foi projetado para (1) avaliar como a distribuição de Hg em plantas (2) de que forma as plantas iram reter a toxicidade do Hg desencadeando respostas antioxidantes. De fato, a maioria dos parâmetros bioquímicos determinaram a evidência de respostas diferentes por concentrações diferentes de Hg no sedimento (s1 e s2) e (3) as plantas poderiam ou não modificar sua composição lipídica por toxicidade de Hg através da metodologia UPLC-MS. Este estudo demonstrou que ambas as espécies de plantas restringiam a absorção de Hg. No entanto, o processo foi mais eficiente em H. portulacoides. Foram observadas diferenças na quantidade de Hg acumulada por ambas as espécies. Os padrões de alocação também diferem entre as espécies. H. portulacoides apresentou diferentes níveis de Hg entre folhas, caules e raízes, enquanto J. maritimus acumulou os níveis mais elevados de Hg nas raízes. A conjugação dos processos, absorção e translocação resultou em concentrações semelhantes de Hg em caules e folhas e níveis de Hg muito elevados em raízes de J. maritimus. Os resultados obtidos demonstram que o Hg gerou danos oxidativos nas raízes de ambas as espécies e nas folhas de H. portulacoides. As diferenças na LPO entre espécies que se obteve refletem não apenas o nível de Hg acumulado e distribuição de Hg, mas também a capacidade de desencadear mecanismos de defesa. J. maritimus foi capaz de aumentar os níveis proteicos e atividade DHAR em raízes e rizomas e GSTs em rizomas. H. portulacoides não conseguiu induzir respostas enzimáticas antioxidantes. Contudo, nas folhas as moléculas antioxidantes como carotenoides e α-tocoferol foram aumentadas. No estudo do lipidoma, as espécies também apresentaram diferenças. Em H. portulacoides, os fosfolípidos diminuíram em todos os órgãos analisados, o que pode sugerir a alteração da permeabilidade da membrana. Além disso, os galactolípidos diminuíram a eficiência na fotossíntese. No entanto, o α-tocoferol aumentou, proporcionando assim uma melhor proteção às membranas de cloroplastos e manutenção da atividade fotossintética. Em J. maritimus, as alterações lipídicas só foram detetadas em raízes e rizomas, aumentando a permeabilidade lipídica e explicando a maior bioacumulação de concentrações elevadas de Hg. Os fito-esteróis diminuíram significativamente nas raízes e levaram a alterações da membrana de permeabilidade. O α-tocoferol diminuiu em ambos os órgãos de J. maritimus, demonstrando a ineficiência para a contaminação por Hg. Este estudo pode ser um ponto de partida para novos trabalhos, nomeadamente em outros sapais, em outras espécies e com outros metais. Compreender os mecanismos inerentes à tolerância de metais pesados em plantas de sapais e as mudanças na composição lipídica são importantes para detetar o impacto dos metais nestes ecossistemas.
Longhinotti, Maira. « Ambiente fisico e linguaggio ambientale nel processo di rigenerazione affettiva dallo stress in camere di degenza pediatrica ». Doctoral thesis, Università degli studi di Ferrara, 2015. http://hdl.handle.net/11392/2389070.
Texte intégralGressler, Sandra Christina. « O descanso e a teoria dos ambientes restauradores ». reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/15845.
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Descansar é, em sua essência, o relaxamento físico e mental, sendo assim, os comportamentos que ultrapassam o relaxamento unicamente físico podem, até certo ponto, ser compreendidos como comportamentos de restauração? Estudos sobre ambientes restauradores (restorative environments) enfatizam os benefícios físicos, mentais e sociais que alguns ambientes podem propiciar e sugerem que as atividades em ambientes naturais reduzem o estresse da vida diária, promovendo a recuperação ante os desgastes cotidianos. Estes estudos, apesar de pontuais em seus resultados, não unificam as diferentes possibilidades de restauração. Considerando a importância dos ambientes restauradores na promoção do bem-estar e a pouca investigação a respeito do tema conduzida no cenário nacional, decidiu-se, na presente pesquisa, verificar a aplicabilidade do conceito dos ambientes restauradores no contexto brasileiro, mensurar a relação de conexão dos indivíduos com a natureza e indagar a respeito dos ambientes e comportamentos de descanso. Busca-se alcançar esse objetivo ao: a) identificar e analisar o conhecimento comum dos termos “estresse”, “cansaço mental”, “recuperar-se do estresse” e “recuperar-se do cansaço mental”; b) identificar as formas de contato diário dos seres humanos com a natureza; c) identificar os ambientes/atividades de descanso; d) verificar se os ambientes de descanso correspondem aos ambientes restauradores; e) verificar o fator tempo relacionado ao comportamento de descanso; f) verificar se há relação entre os comportamentos de descanso e a conexão com a natureza; e g) investigar se há relação entre a capacidade de atenção e os diferentes comportamentos de descanso. Participaram deste estudo, operários de diferentes empresas, nas quais determinadas funções exigem atenção concentrada, além de estudantes do ensino médio de diferentes escolas. Foram usados, para a obtenção dos dados, entrevista, escala de conexão com a natureza, questionário e o teste de atenção concentrada. Os dados obtidos foram cotejados com os estudos de restauração da atenção (Kaplan & Kaplan, 1989) e da recuperação ao estresse (Ulrich, 1983). Segundo os resultados, atendem os requisitos de restauração, os ambientes com características naturais quando compatíveis aos anseios pessoais (aspectos físicos e distância) e os ambientes residenciais quando atendem às características de refúgio, segurança e expressão própria, característica de território primário. Sugerimos que os processos descritos nos estudos da restauração da atenção ocorrem de forma gradual (hierárquica), respectivamente iniciando com afastamento, seguido por compatibilidade, fascinação e extensão. Sendo estes associados também ao tempo disponível para o descanso. Não apresentam resultados conclusivos as análises corelacionais entre os comportamentos de descanso e os índices obtidos no teste de atenção concentrada ou os escores da escala de conexão com a natureza. Foi possível observar que o comportamento de descanso apresenta relação com as características biodemográficas dos participantes. Constata-se a necessidade de incluir, nos estudos de ambientes restauradores, além de investigações a respeito das características físicas do ambiente, o comportamento, as relações sociais, as reações subjetivas, à distância e o tempo disponível para o descanso. A complexidade do tema indica a necessidade de estudos multimétodos. Contribuições práticas fornecem subsídios na elaboração de estratégias para a promoção do bem-estar da população. _______________________________________________________________________________________ ABSTRACT
Resting is, in essence, the physical and mental relaxation, so can behaviors that go beyond the merely physical relaxation, to some extent be understood as behavior of restoration? Studies on restorative environments emphasize the physical, mental and social benefits that some environments can provide and suggest that activities in natural environments reduce the stress of daily lives, promoting recovery against the daily wear. These studies, though specific in their results, do not unify the different possibilities of restoration. Considering the importance of restorative environments by promoting well-being, and few researches exploring the subject nationally, it was decided to conduct this research, having as the main objective to verify the applicability of the theory on restorative environments at a Brazilian context, measuring individual connection with nature and inquiring about the environment/behavior of rest. The research sought to achieve its goals by: a) analyzing the knowledge about the themes "stress", "mental fatigue", "recover from the stress" and "recover from mental fatigue"; b) identifying daily ways of humans connection with nature; c) identifying the resting environments/behavior; d) verifying if rest strategies match the restorative environments suggested by restorative studies; e) verifying different rest strategies related to time; f) investigating evidence of a relationship between rest behavior and connection with nature, and g) investigating evidence of a relationship between rest behavior and attention capacity. Workers from different companies in which certain functions require focused attention, and high school students from different schools, participated in this study. Interview, scale of connection with nature, questionnaire and concentrated attention test were used to collect data and information. The data obtained was compared with studies of attention restoration theory (Kaplan & Kaplan, 1989) and stress recovery (Ulrich, 1983). According to the results, environments with natural characteristics that are compatible with personal desires (physical aspects and distance) and residential environments when they fulfill the characteristics of refuge, safety and self-expression, characteristics of primary territory, meet the requirements of restoration. The restoration processes described in the studies of attention restoration theory occur gradually (hierarchically), starting with being away, following compatibility, fascination and extent; also associated with the time available for rest. Results regarding the relation of rest behaviors and concentrated attention test and connection to nature scale were not conclusive. However, it is noted the relation of rest behaviors and participants biodemographic characteristics. Suggesting the need to insert in the studies of restorative environments, not only, investigations regarding the physical characteristics of the environment, but also behavior, social relationship, subjective reactions, distance and time available for rest. The complexity of the theme indicates the necessity for multimethod studies. Practical contributions provide subsidies for developing strategies to promote the welfare of the population. _______________________________________________________________________________________ RESUMEN
El descanso es, en esencia, la relajación física y mental, por lo tanto e los comportamientos que van más allá de la relajación meramente física pueden, hasta cierto punto, ser entendidos como comportamientos de restauración? Los estudios acerca de ambientes restauradores (restorative environments) enfatizan los beneficios físicos, mentales y sociales que algunos ambientes pueden proporcionar y sugieren que las actividades en entornos naturales reducen el estrés de la vida cotidiana, promoviendo la recuperación ante el deterioro cotidiano. Estos estudios, aunque específicos en sus resultados, no unifican las diferentes posibilidades de restauración. Teniendo en cuenta la importancia de los entornos de restauración en la promoción del bienestar y la poca exploración de trabajos acerca del tema realizada en el contexto cultural de Brasil se decidió verificar la aplicabilidad de la teoría general de los entornos de restauración en el panorama nacional, medir la relación de conexión de los individuos con la naturaleza y cuestionar los ambientes de descanso. Estos objetivos se alcanzan al a) identificar y analizar el conocimiento común de los términos "estrés", "cansancio mental", "recuperación del estrés" y "recuperación del cansancio mental"; b) identificar las formas de contacto cotidiano entre los seres humanos y la naturaleza; c) identificar los entornos/actividades de descanso; d) verificar si los ambientes de descanso corresponden a los entornos de restauración propuestos en la teoría; e) verificar el factor tiempo relacionado al comportamento de descanso; f) investigar si hay relación entre la elección de los ambientes de descanso y la conexión con la naturaleza; y, g) buscar pruebas de la relación entre la capacidad de atención y las opciones de ambientes naturales para el descanso. Los participantes del estudio fueron trabajadores de distintas empresas en las cuales determinadas funciones requieren atención concentrada, además de estudiantes de secundaria de diferentes escuelas. Fueron utilizados para la recolección de datos, entrevistas, escalas de conexión con la naturaleza, cuestionario y el teste de atención concentrada. Los datos se compararon con la teoría de la restauración de la atención (Kaplan y Kaplan, 1989) y de la recuperación de estrés (Ulrich, 1983). Los resultados indican que los ambientes con características naturales son compatibles con los deseos personales y factores como la distancia y entornos residenciales cuando son compatibles con las características de refugio, seguridad y libre expresión, característica del territorio principal, satisfacen las necesidades de restauración. Proponemos que los procedimientos de restauración descritos en la teoría ocurren de manera gradual (jerárquica) empezando con el afastamiento, seguido por la compatibilidad, la fascinación y la extensión. Éstos están también asociados con el tiempo disponible para el descanso. No presentan relación co la elección de los comportamientos de descanso, la prueba de la atención enfocada y la escala de la conexión con la naturaleza. Fue posible observar que el comportamiento de descanso presenta relación con las características bio-demográficas de los participantes. Se llegó a la conclusión de que la necesidad de introducir en los estudios de entornos restauradores, además de las características físicas del medio ambiente, el comportamiento, las relaciones sociales, las reacciones subjetivas y el tiempo disponible para el descanso. La complejidad del tema indica la necesidad de un estudio multi-método. Aportes prácticos proporcionan beneficios que ayudan en el desarrollo de estrategias para la promoción del bienestar de la población.
Santos, Sílvia Camila Vasconcelos dos. « Cellular energy allocation of Chironomus riparius under toxic stress ». Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/9869.
Texte intégralA alocação de energia celular (CEA) é um biomarcador energético que integra a análise das reservas energéticas disponíveis (conteúdo total de proteínas, lípidos e carbohidratos) e da energia consumida pelo organismo (sistema de transporte de eletrões), fornecendo uma análise global do estado metabólico dos organismos. Neste trabalho, este biomarcador foi usado como uma potencial ferramenta para a avaliação de efeitos do Cádmio e do inseticida Movento em larvas da espécie Chironomus riparius. Alterações no CEA foram comparadas com efeitos no crescimento e emergência dos organismos, de modo a avaliar a sensibilidade e relevância do CEA como uma ferramenta na avaliação de risco ecológico. Cádmio e Movento tiveram efeitos negativos no crescimento e na emergência dos organismos e o biomarcador energético revelou uma menor sensibilidade que os outros parâmetros para ambos os contaminantes. Contrariamente à exposição ao inseticida, onde não foram observadas diferenças na alocação de energia, o cádmio causou um aumento na energia consumida – provavelmente devido a um maior gasto de energia para a destoxificação. Uma menor quantidade de energia disponível irá, provavelmente, provocar uma redução nas taxas de desenvolvimento com consequências na emergência, afetando assim a reprodução e a dinâmica da população. Alterações na alocação de energia, dependendo da sua magnitude, podem estar intimamente relacionadas com alterações nos parâmetros individuais do ciclo de vida dos organismos (crescimento e reprodução), podendo ter consequências negativas em níveis de organização biológica superiores. Isto pode reforçar a importância de utilizar estes biomarcadores energéticos como uma potencial ferramenta na avaliação de risco ambiental. Contudo, e apesar do CEA ser utilizado como um biomarcador sensível em diferentes espécies de invertebrados, os resultados deste trabalho mostram que a sua utilização e interpretação em organismos modelo com ciclos de vida rápidos e complexos, como C. riparius, deve ser feita de forma cuidadosa.
The Cellular Energy Allocation (CEA) is an energetic biomarker that integrates the assessment of the available energy reserves (total content of protein, lipids and carbohydrates) and the energy consumed by the organism (electron transport system), providing an overall assessment of the metabolic status of the organisms. In this work, this biomarker was used as a prospective tool to assess the effects of Cadmium and the insecticide Movento to exposed midge larvae, Chironomus riparius. Alterations in CEA were compared to effects on growth and emergence in order to evaluate CEA’s relevance and sensitiveness as a tool in environmental risk assessment. Cadmium and Movento impaired the growth and emergence of the organisms and the energetic biomarker revealed less sensitivity than the other endpoints for both contaminants. Contrary to the insecticide exposure, where no differences in the energy allocation were observed, cadmium caused an energy allocation shift – towards the increase of the consumed energy - probably due to a higher energy demand for toxic defense purposes. Less energy available will most probably reduce development rates with consequences on the emergence thus affecting reproduction and population dynamics. Changes in the energy allocation, depending on their magnitude, are closely related to changes in the individual life cycle traits (growth and reproduction) and may therefore have major impacts in higher levels of biological organization. This may strengthen these energy based biomarkers as prospective tools in environmental risk assessment. Nevertheless and despite CEA’s potential use as a sensitive biomarker in different invertebrates species the results of this work call for a careful use and interpretation of CEA assessment in model test species, such as C. riparius, which have a rapid and complex life-cycle.
CESARETTI, SABRINA. « Plant co-existence mechanisms related to stress and disturbance intensities in sub-Mediterranean and sub-desertic grassland systems ». Doctoral thesis, Università degli Studi di Camerino, 2012. http://hdl.handle.net/11581/401800.
Texte intégralELOH, KODJO. « Exploration of New Oxidative Stress Nematicidal Compounds and Valorization of Satureja montana L. Essential Oils and Hydrolates as Plant Biopesticides ». Doctoral thesis, Università degli Studi di Cagliari, 2019. http://hdl.handle.net/11584/260403.
Texte intégralHerrera, Mautino Milagros Denisse. « Influencia de la Gráfica Ambiental y la Iconoplástica en el estrés de pacientes pediátricos hospitalizados ». Bachelor's thesis, application/msword, 2019. http://hdl.handle.net/10757/626319.
Texte intégralThe present research allows to know the problem of child stress in paediatric patients due to the lack of humanization of the hospital space. The general objective is to demonstrate that the Graphic Design applied through the Environmental Chart and the Iconoplastic influences the humanization of a health space to reduce the stress of children in hospitalization in the Hospital National Cayetano Heredia, the hypothesis is therefore generated: "The Graphic Design applied through the Environmental Chart and the Iconoplastic influences the humanization of a health space to reduce the stress of children in hospitalization at the Cayetano Heredia National Hospital." The approach used for this research is mixed. The study is experimental – pure experiments. The population consisted of 14 paediatric patients from 5 to 12 years of age in the area of Pediatric Hospitalization. The survey and focus group were used as data collection techniques for variables, hospitalization and child stress; the questionnaire for both variables was used as a tool. As a solution, the graphic intervention of the hospital environment to pediatricize and humanize the area of hospitalization. This is based on the results obtained and the need to adapt a hospital space to children’s needs. In conclusion, the response of paediatric patients was positive and the results of the tests were 90% success, so the hypothesis could be validated.
Trabajo de investigación
Pereira, Ruth. « ARIS - análise de risco numa área classificada sujeita a Stress Químico ». Doctoral thesis, Universidade de Aveiro, 2004. http://hdl.handle.net/10773/16367.
Texte intégralA análise de risco converteu-se numa ferramenta poderosa para os processos de tomada de decisão relativos à recuperação de áreas contaminadas. Em Portugal, este processo está pouco desenvolvido e a falta de equipas multidisciplinares de especialistas é frequentemente mencionada como um obstáculo. Consequentemente, a maioria das acções de recuperação de áreas contaminadas é baseada em aspectos hidrológicos e geoquímicos dando pouca atenção às comunidades biológicas locais e às suas respostas aos agentes químicos. Contudo, estes dados são fundamentais para avaliar a verdadeira biodisponibilidade dos contaminantes e subsequentemente os riscos reais que são colocados à saúde dos seres humanos e aos sistemas naturais. Com o objectivo de resolver alguns destes constrangimentos, o modelo conceptual proposto pela Agência de Protecção Ambiental Norte Americana (US EPA) foi utilizado como base para planear a avaliação dos riscos, para a saúde humana e sistemas ecológicos, colocados pela exposição a elevadas concentrações de metais pesados presentes na proximidade da Mina de S.Domingos (Sudeste Alentejano). A informação científica disponível para a área e a sua validade para a análise de risco foram avaliadas durante a fase de formulação do problema. Esta etapa apresentou ainda como produtos finais um modelo conceptual e um plano para a avaliação da exposição e caracterização dos efeitos. O presente estudo centrou-se fundamentalmente nas tarefas referentes ao solo. A análise estatística multivariada de parâmetros físico-químicos e microbiológicos do solo permitiu discriminar as áreas onde a biodisponibilidade e subsequentemente a toxicidade dos metais presentes no solo parece ser maior. Os níveis de metais (sobretudo As e Cd) registados em tecidos de ratazanas e ratinhos capturados na área de mineração, assim como as alterações histopatológicas observadas nos seus diferentes órgãos forneceram novas evidências relativamente à biodisponibilidade de metais na proximidade da mina. Estes resultados aumentaram as preocupações relativamente à exposição de espécies vulneráveis presentes nesta zona assim como do gado e subsequentemente dos humanos. A exposição dos habitantes locais a metais essenciais como o Mn foi comprovada através da análise de cabelos. A exposição a elementos tóxicos como o As, através da ingestão de produtos animais produzidos localmente (e.g. carne, queijo, leite) foi igualmente sugerida pela análise de um questionário que acompanhou a recolha de amostras de cabelo. Todos os estudos realizados justificam a necessidade de se prosseguir a análise de risco planeada para a zona.
The risk assessment process becomes a powerful tool to provide sound scientific bases for decision-making processes, regarding reclamation of contaminated areas. In Portugal, the risk assessment process is in its early years and the lack of multidisciplinary teams of experts is frequently mentioned as the main obstacle to its implementation. Therefore, the majority of cleaningup and reclamation actions are mainly supported by hydrological and geochemical properties, without having under consideration biological and toxicological data of the contaminated areas. However, this data is important to assess the bioavailability of contaminants and, subsequently, the real risks to humans and ecosystems health. Assuming humans as components of the terrestrial and aquatic ecosystems, the ecological risk assessment framework proposed by the US Environmental Protection Agency was used to plan an integrated assessment of risks posed by the high concentrations of metals, scattered in the vicinity of S. Domingos mine (Southeast Alentejo, Portugal), to local inhabitants and ecological systems. In the problem formulation phase, the scientific information available for the area was collected and analysed, data gaps were identified, as well as a conceptual model and an analysis plan were presented. Considering some of the tasks planned within the exposure and effects characterisation the present study focused mainly on the soil compartment. Multivariate statistical analysis of soil physical, chemical and microbiological parameters identified sub-areas of great metal’s bioavailability and subsequently of great toxicity. The levels of metals (mainly Cd and As) found in the tissues of mice and rats captured in the mining area, and the histopathological changes observed on different organs provided another line of evidence about the bioavailability of metals and their subsequent toxicity in the vicinity of the mining area. These results caused concern about endangered and vulnerable predator species in the area as well as about breeding cattle and subsequently human health. As far as humans are regarded, the assessment of scalp hair residues recorded high concentrations of essential elements such as manganese. The exposure to toxic elements such as As via animal products locally produced (e.g. meat, milk and cheese) was also suggested and agreed with data recorded on rodents. All the data obtained supports the prosecution of the risk assessment process planned for the area.
Kuhnen, Shirley. « Avaliação do uso das proteínas de estresse (Hsp70) como biomarcadores de contaminação ambiental no mexilhão Perna perna ». Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/79921.
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A expresso das proteínas de choque térmico (Hsp), também denominadas proteínas de estresse, é alterada em função da presença de agentes estressores no ambiente e é uma resposta altamente conservada, estando presente desde bactérias até o homem. O presente estudo teve como objetivo investigar a expressão das Hsp(s)70 nas brânquias do mexilhão Perna perna através de um experimento realizado em campo, complementado por um outro em laboratório. Neste último, os animais foram expostos a diferentes concentrações de cobre (20, 50, 70 e 1000mg/L) por 7 dias. Diferenças significativas (p<0,05) nos níveis de Hsp(s)70 foram detectadas, por Western Blotting, nas brânquias dos animais mantidos na menor concentração de cobre. No estudo realizado no campo, os mexilhões foram transplantados de uma região considerada não contaminada, Sambaqui, (SAM) para outra considerada contaminada, Ponta do Lessa (PL), onde foram mantidos por diferentes períodos durante o verão e o inverno. Foi observado um aumento significativo (p<0,05) nos níveis de Hsp(s)70 nas brânquias dos animais mantidos na Ponta do Lessa por 7 e 30 dias no inverno. De acordo com os resultados obtidos, destacamos algumas perspectivas para a continuidade deste estudo e sugerimos o uso potencial das Hsp(s)70 em programas de monitoramento ambiental com o mexilhão Perna perna, recomendando, ainda, a realização da análise conjunta de outros biomarcadores e de parâmetros físico-químicos complementares.
Horváth, Vivien 1990. « Unravelling the role of transposable elements in the eukaryotic stress response ». Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/669757.
Texte intégralEl estrés ambiental es un aspecto importante de la vida y un factor limitante en la supervivencia y distribución de las especies. Entender la respuesta a estrés a nivel de organismo y los mecanismos desarrollados para enfrentarlo son indispensable para mitigar sus efectos negativos. Muchos estudios se han centrado en el rol de los polimorfismos de nucleótido único, mientras que otros potentes mutágenos, como son los elementos transponibles (TEs), han sido ignorados. En la primera parte de esta tesis, hemos estudiado la contribución de los TEs en la respuesta eucariótica a estrés utilizando un enfoque específico al mecanismo molecular. Al estudiar seis tipos de respuesta a estrés diferentes en humanos y en Drosophila melanogaster hemos demostrado que los TEs pueden regular la expresión de genes de respuesta a estrés gracias a la adición de sitios de unión de factores de transcripción. En la segunda parte, hemos escogido un enfoque específico de estrés y hemos descrito las bases transcriptómicas y fisiológicas de la tolerancia a la desecación en D. melanogaster. Además, hemos observado que los los TEs podrían estar involucrados en la respuesta a estrés por desecación, aunque no parecen ser la principal mutación causante de la respuesta a este estrés. En conjunto, se muestra que los TEs tienen un rol importante en la respuesta eucariótica a estrés, sin embargo, su contribución parecería ser específica del estrés.
Rae, Mariana Beu. « Efeitos do enriquecimento ambiental sobre comportamentos induzidos pelo etanol em camundongos Swiss : envolvimento da circuitaria do estresse ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/42/42136/tde-13082014-164817/.
Texte intégralEnvironmental enrichment (EE) presents positive effects upon alcohol addiction and its possible that EE acts as a mild stressor, which would help animal cope better with future stressful situations. Mice were separated in three groups: control (CO), EE and stress (ST). We studied the effects of EE and ST on anxiety-like behavior, episodic memory, conditioned place preference (CPP) to ethanol, corticosterone and quantity of oxytocin receptor. EE decreased the latency to enter the open arm, suggesting an anxiolytic effect, unlike ST. Memory did not differ between groups and EE demonstrated a higher preference to ethanol compared to CO. Corticosterone levels didnt differ among groups. Autoradiography showed decreased binding of OT in the olfactory nuclei and frontal cortex of EE animals and enhanced binding of OT in the amygdala of ST animals compared to CO, suggesting higher pro-social behavior and higher anxiety-like behavior, respectively. We conclude that the environment is capable of affecting important brain circuitries involved in stress and drug addiction.
Rodrigues, Bruna. « Etologia aplicada ao enriquecimento ambiental para macacos-prego (Sapajus spp.) semi-cativos ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-05032015-152804/.
Texte intégralNowadays there is a big ethic concern in improving the well-being of captive and semi-captive animals. One of the most efficient forms of doing that is applying environmental enrichment techniques. To evaluate its efficiency, the ethological approach applies environmental stimuli and analyzes the behavioral changes caused by them by correlating with possible adaptive functions. This work has analyzed the influence of a sequential and cumulative environmental enrichment method on the behavior of 27 individuals of a semi-captive group of capuchin monkeys (Sapajus spp.) at Parque Ecológico do Tietê, São Paulo. The provision of rocks and nuts for the task of nutcracking was utilized as cognitive-food enrichment, whereas suspended nets were utilized as physical enrichment. The experimental design was composed of four conditions: 1) Base Line, observations made before the introduction of the enrichment; 2) Enrichment with nuts Protocol I, the nuts were provided at a single cracking site; 3) Enrichment with nuts, Protocol II, the nuts were equally distributed at three cracking sites; and 4) Physical Enrichment, two nets were placed in open areas of the island, beside the provision of nut at three sites. The registry of behavior was made using the Focal Scan and All Occurrences methods. The adult subordinate males were the only individuals of the group that presented abnormal behaviors, as they were under great psychosocial stress in the group hierarchy. The frequency of abnormal behaviors was altered, especially in the Physical Enrichment condition, when a drastic decrease of these behaviors was seen. The introduction of nets provided refugee and enabled conflict avoidance, increasing the sensation of environment control. Besides that, some of the individuals had a increase of spatial proximity and showed affiliative behaviors with other subordinates, which would be an adaptive strategy adopted to reduce stress. The rate of agonistic behaviors was seen to have increased with the introduction of cognitive-food enrichment. The increase of intergroup direct competition was already expected due to the characteristics of the enrichment provided and this behavioral change of the group can be considered typical of wild primates. There was no significant increase in grooming and social play rates at any of the conditions. There was significant change of the group cohesion only under the Physical Enrichment condition, where the biggest interindividual distance measures and the formation of new proximity relations in the group were seen. The appearance of new dyads involved in grooming and the reduction of the group size due to high mortality explain the increased group cohesion observed under this condition. The introduction of nets on superior layers elicited less terrestriality, by having a significant increase of the frequency of use of substrates Above 1,5m in detriment of use of substrates at the ground level under the Physical Enrichment condition, showing a preference for substrates above the ground by these animals. The enrichment technique applied is justified by the fact that it is a new element on the routine of these animals, which helped them use their time, effort and cognitive capacity and interact socially
Notarfrancesco, Sarah <1991>. « Purple bacteria for the biotechnological valorisation of agro-industrial streams ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10386/1/PhD%20thesis_Sarah%20Notarfrancesco.pdf.
Texte intégralGomiero, Alessio <1974>. « Applicazione di indici biologici di stress per la valutazione dell'impatto ambientale generato dall'attività di piattaforme per l'estrazione di idrocarburi gassosi ». Doctoral thesis, Università Ca' Foscari Venezia, 2009. http://hdl.handle.net/10579/375.
Texte intégralMartins, Pedro Miguel Carvalho Diogo Carreiro. « Mecanismos de inflamação brônquica resultantes da exposição a factores ambientais ». Doctoral thesis, Faculdade de Ciências Médicas. Universidade Nova de Lisboa, 2012. http://hdl.handle.net/10362/8339.
Texte intégralAlmeida, Eduardo Alves de. « Avaliação de variações bioquímicas em moluscos bivalves em resposta ao estresse ambiental ». Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-06082008-150607/.
Texte intégralIn this work, some biochemical systems were evaluated in different tissues of bivalve mollusks, in response to different stress, in order to verify the possibility of use of these systems as pollution bioindicators in marine environmental monitoring studies, as well as to verify the influence of environmental variations not related to pollution on these systems. Mussels Mytella guyanensis and Perna perna collected in polluted environments presented higher levels of DNA and lipid damage, compared to mussels from a reference site. Mussels exposed to different metals also presented high levels of DNA and lipid damage. These data indicates that the lesions evaluated in mussels showed good responses to the contaminants, suggesting its use as biomarkers of marine contamination. On the other hand, other environmental variations such as air exposure cyvles, seasonality and variations in salinity also caused changes in the levels of DNA and lipid damage, indicating that the collection procedure of mussels, including observations of the environment conditions, should be considered for better interpretation of the results. In mussels exposed to different metal at different time intervals, the activities of the antioxidant enzymes catalase (CAT), glutathione peroxidase (GPx), phospholipid hydroperoxide glutathione peroxidase (PHGPx), and glutathione S-transferase (GST), as well as the levels of reduced glutathione (GSH) and lipid peroxidation were evaluated. Some oscillations were observed in these parameters, related to the susceptibility of the digestive gland to lipid peroxidation. Major relationships were observed between the activity of PHGPx and the levels of lipid peroxidation, suggesting a protective role of PHGPx against lipid peroxidation and its modulation by metals. The levels of serotonin (5HT) and dopamine (DOPA) were also evaluated in digestive gland and muscle tissues of the mussels, being observed 5HT and DOPA depletion in both tissues. In muscle tissues, this would be related to the tonic catch contraction of muscle fibers in response to the metal exposure, since 5HT and DOPA are involved in this process. Experiments of exposure of mussels to air and re-submersion were also done to verify the effects on 5HT and DOPA levels. When mussels were exposed to air, decreases in 5HT and DOPA were observed, and when mussels were re-submersed, the levels back to the control values, which would also be related to the muscle contraction. No differences were observed in digestive glands. Little variations in 5HT and DOPA levels were observed between mussels collected at different times of the day, indicating a role of these compounds in the control of biological rithms. Additional studies were done, were the oxidative melatonin product by singlet molecular oxygen was characterized by high performance liquid chromatography coupled to mass spectrometry (HPLC/MS), and proton and carbon nuclear magnetic resonance. The chraracterized product was the kynurenine N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK). Along this study, the theory that the reaction of nitriles with hydrogen peroxide in alkaline solutions were confirmated through monitoring of the ligh emmited by singlet oxygen and the detection of the product formed (acetamide). Also, a new method for the simultaneous detection of melatonin and AFMK with high specificity and sensibility by HPLC/MS were developed.
Espírito, Santo Bruno César do. « RESPOSTA ADAPTATIVA DE LINHAGENS NÃO AMBIENTAIS DE Escherichia coli FRENTE AO HERBICIDA GLIFOSATO ». Universidade Estadual de Ponta Grossa, 2015. http://tede2.uepg.br/jspui/handle/prefix/2657.
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Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná
O aumento na produção agrícola deve-se, em boa parte, pelo uso intensivo de agroquímicos, os quais assumem papel relevante. Porém, um dos impactos gerados pelo seu uso é a mudança estrutural e populacional das microbiotas do solo, que precisam de alguma forma tolerar esse xenobióticos para subsistir. São questionados se mecanismos de tolerância são selecionados por pressão seletiva sobre fenótipos específicos ou se existem mecanismos plásticos de adaptação, prescindindo de agentes seletivos específicos. O objetivo deste trabalho foi avaliar os mecanismos de adaptação e respostas celulares, particularmente de isoenzimas de catalase em Escherichia coli, ao contato com o herbicida glifosato, sem seleção prévia para esse herbicida. Resultados mostraram que a deleção em katG permitiu uma tolerância a doses mais elevadas do herbicida, e que a linhagem katE responde melhor as espécies reativas de oxigênio. Taxas de crescimento nos tratamentos com doses elevadas do herbicida se mostraram menores em relação ao controle, mostrando o efeito tóxico sobre as células bacterianas. As taxas de peróxido de hidrogênio foram aumentadas nos tratamentos com herbicidas, o que provavelmente contribuiu para a diminuição no crescimento bacteriano. A linhagem katE foi a mais eficiente em responder aos níveis de peróxido de hidrogênio induzidos pelo glifosato. Os níveis de MDA mostraram-se parecidos em tratamentos com 50 x glifosato em katE e em katG, corroborando a efetividade e especificidade da enzima HPI (katG) na fase log. Considerando que a E. coli não apresentou um contato prévio com o glifosato, sendo uma linhagem desenvolvida para estudos de laboratório, e não adaptada ao ambiente, o sistema de defesa encontrado nessas linhagens pode ser considerado como modelo para outras bactérias de solo, amplo, não específico para o glifosato. Um sistema de respostas não específicas como esse podem aumentar o valor adaptativo de bactérias em solos agrícolas, nos quais são aplicadas diferentes espécies químicas de herbicidas em um tempo relativamente curto.
The increase in agricultural production is due, in large part, by the intensive use of agrochemicals, which assume a significant role. However, one of the impacts generated by its use is structural change and population of the microbiota of the soil, they need somehow tolerate this xenobiotics to subsist. They are asked whether tolerance mechanisms are selected by selective pressure on specific phenotypes or if there are plastic coping mechanisms, regardless of especific. The selective agents aim of this study was to evaluate the mechanisms of adaptation and cellular responses, particularly isozymes of catalase in Escherichia coli when contact with the herbicide glyphosate, without prior selection for this herbicid.Results showed that deletion in katG allowed a tolerance to higher doses of the herbicide, and that katE lineage responsive reactive oxygen species. Growth rates in the treatments with high doses of the herbicide were lower compared to the control, showing the toxic effect on cells As hydrogen peroxide rates were increased in the treatments with herbicides, which probably contributed to the decrease in bacterial growth . The katE strain was more efficient to respond to hydrogen peroxide levels induced by glyphosate. MDA levels were shown to be similar in treatments with 50 x glyphosate in katE and katG, confirming the effectiveness and specificity of the HPI enzyme (katG) in log. Considering phase that E. coli showed no previous contact with glyphosate, a strain being developed for laboratory studies, and not adapted to the environment, the defense system found that strains can be considered as a model for other soil bacteria, broad, not specific to glyphosate. A system of non-specific responses as this may increase the adaptive value of bacteria in agricultural soils, which are applied in different chemical species of herbicide in a relatively short time.
Pegoraro, Camila. « Bases moleculares da resposta a estresses ambientais em vegetais : arroz, tomate e pêssego ». Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1142.
Texte intégralAbiotic stresses represent large threats to agriculture and food security, since they limit the productivity of the majority of cultivated plants. In order to identify the responses of plants to abiotic stresses and their associations with tolerance under different environmental conditions, concepts and techniques in molecular biology, cell biology and genetics have been used. The identification of genes responsive to stresses can be used to obtain plants tolerant to adverse environmental conditions by genetic transformation or directed crosses. Thus, this study had the objective the establishing of expression profiles of gene belonging to the ERF, HSP, HSF, TIM/TOM and TIC/TOC families in rice and tomato under low O2 stress. Also, the transcriptional profile of peaches under cold stress as obtained. The results indicate that in rice, some members of the ERF family present specific expression according to the stressing agent, while others have overlapping expression among different stresses. Besides, within the ERF family, some genes do present a complex regulation and others a simple regulation. In rice, some genes encode proteins belonging to the TIM/TOM and TIC/TOC complexes present high expression levels 24 hours after anoxia stress. However, after 72 hours under anoxia, the majority of genes were inhibited, suggesting an interruption on the transport of proteins to the mitochondria and chloroplast during the stress period. When the HSP expression profiles of flooding tolerant and sensitive rice cultivars were compared, transcript accumulation occurred for both cultivar types. However, the majority of genes evaluated were more responsive in the sensitive cultivar than in the tolerant, indicating that HSPs have an important association in the response to anoxia stress but are not directly involved in the tolerance. In tomato fruits stored under hypoxia, two sHSPs genes were highly induced by low oxygen levels, indicating a primary action of these genes on keeping cell homeostasis after the stress. In peaches, the application of gibberellic acid acts on preventing the damaged caused by cold by the induction of genes associated to lipid metabolism, cell wall degradation and trehalose synthesis.
Estresses ambientais representam grandes ameaças à agricultura e, por consequência, à segurança alimentar, uma vez que limitam a produtividade da maioria das plantas cultivadas. Buscando identificar as respostas das plantas frente a estresses abióticos e suas relações com a tolerância sob diferentes condições ambientais, conceitos e técnicas de biologia molecular, biologia celular e genética vêm sendo continuamente utilizadas. A identificação de genes responsivos a estresses pode ser utilizada na obtenção de plantas tolerantes a condições ambientais adversas através de manipulação genética ou cruzamentos direcionados entre diferentes genótipos. Desta forma, este estudo teve como objetivo estabelecer o perfil de expressão de genes pertencentes às famílias ERF, HSP, HSF, TIM/TOM e TIC/TOC, em arroz e tomate sob condições de estresse por deficiência de O2. Além disso, buscou-se estabelecer o perfil transcricional de pêssegos sob condição de estresse por frio. Os resultados obtidos demonstram que em arroz, alguns membros da família ERF apresentam expressão específica de acordo com o agente estressor, enquanto que outros apresentam sobreposição de expressão entre os estresses, além disso, dentro da família ERF alguns genes apresentam regulação complexa e outros regulação simples. Em arroz, alguns genes codificadores de proteínas pertencentes aos complexos TIM/TOM e TIC/TOC apresentaram altos níveis de expressão 24 horas após estresse por anoxia. Entretanto, após 72 horas sob condições de anoxia, ocorreu a inibição da expressão da maioria dos genes pertencentes a estes complexos, sugerindo que possa haver uma interrupção no transporte de proteínas para a mitocôndria e cloroplasto durante este período de estresse. Ao comparar cultivares de arroz tolerante e sensível ao alagamento, verificou-se que houve um acúmulo de transcritos dos genes codificadores de HSPs em ambas as cultivares. Entretanto, a maioria dos genes avaliados foi mais responsiva ao estresse por anoxia na cultivar sensível, do que na cultivar tolerante, sugerindo que genes HSPs têm relação importante na resposta ao estresse por anoxia, mas não estão diretamente envolvidos na tolerância. Em frutos de tomate armazenados sob hipoxia dois genes codificadores de sHSPs foram altamente induzidos por baixos níveis de oxigênio, indicando uma ação primária destes genes na manutenção da homeostase celular após este estresse. Em pêssegos, a aplicação de ácido giberélico atua na prevenção de danos ocasionados pelo frio através da indução de genes associados ao metabolismo de lipídios, à degradação da parede celular e à síntese de trealose.
Martins, Paula Fabiane. « Aspectos da regulação metabólica bacteriana em resposta a herbicidas : um enfoque ao sistema antioxidante ». Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11137/tde-30052012-103433/.
Texte intégralThe environmental contamination by pesticides is an increasing concern, as frequently showed in studies with detection of these compounds in water and soil. In fact, the understanding of pesticide effect on non-target organisms is necessary given the importance of pesticide and its sustentable use. The study of bacterial adaptive response to pesticide can show how the metabolic regulation happens, as well as provide new data about biotransformation of these xenobiotics. For this propose, firstly the biodegradation analyse showed the Enterobacter asburiae SD1 strain has capacity to degrade the s-metolachlor herbicide in around 30% of your initial concentration (1,25 mM), in 13 h of cultivation in mineral medium. However, the degradation was also observed on the presence of alternative carbon source, what suggests, together the differential growth, the bacteria can show an adaptive response to different conditions represented by the media constitution. The antioxidant system, a global sensor to stress, was evaluated in E. asburiae SD1 cultivated in different media, to see what is the effect of s-metolachlor herbicide in the antioxidant response. It was possible to observe preferential pathways activated according to medium characteristics, such as the activation of glutathione Stransferase in the presence of only s-metolachlor as carbon source. This result was explained by the bacterial need to recognize and metabolize a new molecule. On the other hand, in the presence of alternative carbon source, in addition to herbicide, the pathways to combat oxidative stress, as those constituted by catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR), were firstly activated. Besides this, the differential activation was observed among the isoenzymes of CAT and SOD, wich special attention to Mn-SOD, which one had an important role in the adptive responde to herbicide. This affirmation was justified when de delection of sodA gene (Mn-SOD) induced membrane damage and disruption in the cooperative work of antioxidant enzymes in bacteria exposed to s-metolachlor. Finally, the integration of different levels of metabolism in the antioxidant response was showed through study with a pathway envolved in the translational control which has the elongation factor-P (EFP) as one important protein. This enzyme acts in the fidelity during the protein synthesis, and its absence, caused by efp gene delection, as well others two protein important to activate the EFP, induced the oxidative stress, increased by the paraquat herbicide. The present work collects relevant results for understanding of the role of bacterial antioxidant system in the stress condition induced by herbicide presence, and also offers important data about integration and regulation of biochemical pathway in the antioxidant system activation for an efficient adaptative response.
Auad, Alessandra Regina Brito. « Interferência de fatores ambientais e emocionais na voz de docentes universitários ». Pontifícia Universidade Católica de Goiás, 2007. http://localhost:8080/tede/handle/tede/3058.
Texte intégralThe voice is a human language component reinforced or weakened by the vocal dinamics defined by the voice impact of the talker in the listener, driving him apart or approximating him of his interlocutor. Purpose: identify the impact of environmental and emotional factors in professors in Goiânia,Goiás. Methods: 150 professors took part in the study, both sexs, teaching in 10 state, federal and private universities, from August 2005 to May 2006.The data was collected by Voice Activity and Participation Profile. The data was analyed through the Program Statistical Package for Social Sciences, (SPSS) 13.0 version. Results: The age group to include 25-65 years old and predominance of 25-35 years old group. The sex ratio of women to boys was 65% to 35%. There was predominance of teaching time of 1-9 years and the worklood between 1-20 hours (46%). The study showed that 93% of the professor s presented interference of the voice in the daily communication, 91% felt emotionally affected by vocal alterations; 88% mentioned to limit their activities in the presence of the voice desorders; 84% refered the voice alteration caused pressure in work and social communication. In relation to the environmental factors, the most importante ones were students talking and their number in classroom (58%), airconditioning (29%), external noise(26%) and the physical space and acoustics distribuition of classroom (16%). About the emotional factors the anxienty (44%). The most used coping tactics were hydration(42%), speak lower or avoid speaking (35%). The most relevante resilience factor was the professors dealing with students (31%).Conclusion:This reseach evidenced the precarious work conditions, the fails infrastructure of the universities as in the coping strategies used by the professor, constitute a determinan factor to unleassh the voice alterations.
A voz é o componente de linguagem humana reforçada ou enfraquecida pela dinâmica vocal definida pelo impacto que a voz do falante causa no ouvinte, distanciando ou aproximando de seu interlocutor. Objetivo: identificar as interferências de fatores ambientais e emocionais na voz de docentes universitários em Goiânia, Goiás. Método: Participaram do estudo 150 docentes universitários, de ambos os sexos, lecionando em 10 universidades estaduais, federais e privadas, no período de agosto de 2005 a maio de 2006. A coleta de dados utilizou o Protocolo Voice Activity and Participation Profile. Os dados foram analisados através do Programa Statistical Package for Social Sciences, (SPSS) versão 13.0. Resultados: A faixa etária compreendeu 25 a 65 anos e houve predomínio de idade de 25 a 35 anos (48%). A proporção entre gêneros foi de (65%) feminino e (35%) masculino. Predominou o tempo de magistério de 1 a 9 anos (52%) e carga horária entre 1 e 20 horas (46%). O estudo mostrou que 93% dos docentes apresentaram interferência da voz na comunicação diária; 91% sentiram-se afetados emocionalmente por apresentarem alterações vocais; 88% mencionaram limitar suas atividades na presença de desordem vocal; 84% referiram que a alteração vocal causou pressão no trabalho e na comunicação social. Em relação aos fatores ambientais, os mais relevantes foram às conversas e número de alunos em sala de aula (58%), ar condicionado (29%), ruído externo (26%) e a distribuição do espaço físico e acústico da sala de aula (16%). Quanto aos fatores emocionais, a ansiedade foi citada por 44%. As táticas de coping mais utilizadas foram hidratação (42%) e falar baixo ou evitar falar (35%). O fator de resiliência mais citado pelos docentes foi o domínio ao comportamento dos alunos (31%). Conclusão: Esta pesquisa evidenciou que a precariedade das condições de trabalho, as falhas nas infra-estruturas das universidades e as estratégias de coping usados pelos docentes, constituem um fator determinante para o desencadeamento de alterações vocais.
Megiato, Érica Insaurriaga. « Análise da fragilidade ambiental da bacia hidrográfica do Arroio Pelotas, RS ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/30379.
Texte intégralThe present study examines the environmental fragility of the Hydrographic Basin of the Arroio Pelotas (HBAP), RS, with the use of a methodology that integrates the study of its physical and socioeconomic aspects. The HBAP has an area of approximately 910 km², covering part of the territory of the municipalities of Pelotas, Canguçu, Arroio do Padre and Morro Redondo. The final result is the letter of environmental fragility of the watershed under study, which was based on the thematic studies and mapping of geology, geomorphology, soils and land use. The study unit is located on two important morphosculptural provinces of the state of Rio Grande do Sul; in the northern portion of the watershed lies the Uruguayan Plateau South-rio-grandese, which presents plutonic igneous, sedimentary and metamorphic rocks, dating from Precambrian period, in its morphostructure. In the southern portion, toward the mouth of Pelotas stream, is located the unit called the Rio Grande do Sul Coastal Plain, which has the Sedimentary Basin of Pelotas, from the Cenozoic period, for its morphostructure. The altitudes in the study area vary from sea level in the Coastal Plain to about 500 meters in the Uruguayan Plateau Southrio- grandese. Concerning the slopes, they rate as very low at 52% of the total area of the HBAP, and low at 21% of the area, including the entire Coastal Plain and some areas on the Plateau. The sum of average, strong and very strong slopes constitute 27% of the whole watershed of the Pelotas stream; these classes are located entirely in the Uruguayan Plateau South-rio-grandense. As for the types of soils, bruno-gray and red-yellow Argisols predominate in the northern basin, while Planosols predominate in the southern portion. The main land use found in the study area is agriculture (mixed use), representing 55% of the study area. The letter of fragility allowed the analysis of the fragility of the environments, relating to erosion and flood risk. In the HBAP were identified areas with Very Low (3%), Low (26%), Average (52%), Strong (16%) and Very Strong (3%) environmental fragility.
Caniatto, Amanda Raquel de Miranda. « Desempenho e excreção em frangos de corte submetidos a dietas com minerais orgânicos em diferentes temperaturas ambientais ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-31032015-084703/.
Texte intégralThe purpose of this study was to evaluate the use of organic minerals - Cu, Fe, Mn, Se and Zn - in the diet of broiler chickens on performance, carcass yield and the effect on polluting power of poultry waste. Two experiments were conducted in the winter and summer seasons, employing six experimental treatments: T1 - Control - Inorganic Minerals Cu, Fe, Mn, Se, and Zn according to Rostagno et al. (2011), T2 - Organic Minerals, T3 - Reduction of 1/3 from T2, T4 - Reduction of 2/3 from T2, T5 - Increase of 1/3 from T2, and T6 - Increase of 2/3 from T2. 1.080 animals were housed in 36 boxes with 30 birds each, on a litter of wood shavings. In the analysis of excretion, 144 animals was used for total collection of excrement in the periods from 19 to 22 and 33 A 36 days of age. The performance characteristics evaluated were body weight, weight gain, feed intake, feed conversion, productive efficiency index, and carcass characteristics and analysis of trace minerals in the manure and poultry litter. To evaluate the effect of season, environmental analysis (temperature and humidity) and physiological (rectal and surface temperatures - Thermographic image) were measured. In addition, in this study was conducted economic feasibility of the use of minerals. Data were analyzed by analysis of variance using PROC GLM of SAS. The comparison among treatments was performed by regression and between the sources of minerals (organic and inorganic) was used contrast. In winter and summer studies, there was no difference between the sources and performance for supplementation levels and carcass yield in the total period. In winter, however, the excretion results with organic source were higher. In addition, the organic minerals showed higher cost and lower profitability. When comparing the seasons, there is a negative effect on the performance of the summer on physiological parameters and economic analysis. Regarding the sources and levels of trace minerals employees, the results indicate that supplementation should be in accordance with the environmental conditions of creation, thus providing better productive, environmental and economic effect for the poultry activity.
Vasconcellos, Angélica da Silva. « O estímulo ao forrageamento como fator de enriquecimento ambiental para lobos guarás : efeitos comportamentais e hormonais ». Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-30112009-095524/.
Texte intégralThe maned wolf, a vulnerable species, has presented problems related to reproduction and welfare in captivity. This study aimed to find efficient techniques to improve the welfare levels of these animals, as a continuation of previous studies. In order to achieve this objective, we investigated the effects of dispersion of food and possible variables related to individual and gender variability in the behavioural responses to environmental enrichment. We applied environmental enrichment techniques to 11 animals, in three institutions. These techniques consisted of the manipulation of the variety, quantity and complexity of feeding stimulus, with evaluation of behaviour and glucocorticoid metabolites. Baseline and experimental conditions were intercalated in the experimental design. Novel Objects were applied in order to measure individual and gender differences, possibly involved in the responses to the environmental enrichment. Choice Tests were used to evaluate the preference of the animals for searching for food. Enrichment promoted a significant increase in foraging. This increase was stronger in the individuals who had diminished glucocorticoid metabolites concentrations during the enrichment. The gender of the animals had affected the hormonal responses to the procedures. There was also a correlation between the behavioural profiles of females and their hormonal reaction to the enrichment (exploratory females had an increase in the glucocorticoid concentrations, whilst cautious ones had a decrease), a result that was not observed in the males. The Choice Tests indicated a preference for a form of laborious foraging, indicating the great value of these procedures to the captive maned wolves. The emotional profiles and the correlation of these profiles with different hormonal responses to the enrichment are original and relevant to the welfare and conservation areas. Our outcomes point to the importance of an xii evaluation of emotional profiles of captive animals to effectively design procedures to improve welfare of captive animals. In addiction to that, the observed preference for the searching of food, as well as the increased foraging promoted by the techniques suggest that these procedures are efficient to improve the welfare in captive maned wolves.