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1
Stanczyk, Nina M. "An investigation of DEET-insensitivity in Aedes aegypti." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/11828/.
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N,N-Diethyl-m-toluamide (DEET) is one of the most effective and commonly used mosquito repellents. However, during laboratory trials a small proportion of mosquitoes are still attracted by human odours despite the presence of DEET. In this study behavioural assays identified Aedes aegypti females that were insensitive to DEET. The selection of either sensitive or insensitive groups of females with males of unknown sensitivity over several generations resulted in two populations with different proportions of insensitive females. Crossing experiments showed the ‘DEET-insensitivity’ trait to be dominant. In addition to the finding of heritable DEET-insensitivity, unselected culture mosquitoes were shown to change their sensitivity to DEET after brief pre-exposure to the repellent. Female mosquitoes that were sensitive to DEET when first tested became insensitive when retested. Electroantennography showed that mosquitoes that were insensitive to DEET had a reduced response to DEET compared with mosquitoes that were sensitive to it. This was the case both for culture mosquitoes displaying insensitivity to DEET after brief pre-exposure to it, and for the sensitive and insensitive lines selected for several generations. Single sensillum recordings of the selected lines identified DEET-sensitive sensilla in the sensitive line that did not respond to DEET in the insensitive line. This study suggests that behavioural insensitivity to DEET in Ae. aegypti is a genetically determined dominant trait, which can also be temporarily induced by pre-exposure, and resides in changes in sensillum function. These results highlight the necessity for careful monitoring of DEET-insensitivity in the field, and caution when designing laboratory methods for repellency assays.
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Fediuk, Daryl James. "Pharmacokinetic and toxicological characterization of repellent DEET and sunscreen oxybenzone." John Wiley & Sons, Ltd, 2010. http://hdl.handle.net/1993/8112.
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Insect repellent N,N-diethyl-m-toluamide (DEET) and sunscreen oxybenzone are commonly incorporated into commercially available repellent and sunscreen preparations. Both compounds have demonstrated an increased percutaneous permeation and systemic disposition after concurrent application in vitro and in vivo. The permeation enhancement between DEET and oxybenzone not only compromises their respective protective efficacy against biting insects and UV radiation, but also potentiates toxicological properties in susceptible subjects. The pharmacokinetic and toxicological profiles from concurrent use of DEET and oxybenzone were evaluated and compared in this thesis.
DEET and oxybenzone were administered by intravenous and topical routes in rats, either alone and/or in combination, to compare the pharmacokinetics of parent compounds and their primary metabolites in vivo. To evaluate toxicological characteristics, rat primary cortical neurons and astrocytes, and rat hepatoma 1548 cells were exposed to DEET, oxybenzone and their metabolites in vitro, and cell viability was analyzed. Various behavioral testing protocols were also performed to assess arousal, locomotion, habituation, and motor coordination of rats over a 30-day study period.
Concurrent topical application of DEET and oxybenzone enhanced the disposition of DEET and its metabolites in rats, but did not consistently affect the distribution of oxybenzone and its metabolites. The disappearance of DEET from skin application site was accelerated; its apparent elimination half-life was decreased while its plasma and tissue concentrations were predominantly increased. Cellular toxicity occurred at 1 μg/ml for neurons and 7-day exposure for both astrocytes and neurons. Viability of hepatoma cells was also reduced when treated with DEET, oxybenzone and their metabolites, either alone or in combination, most notably after 72 hours of exposure. However, no overt signs of toxicity were observed from behavioral testing in rats after a 30-day topical study.
The pharmacokinetic data obtained was beneficial in understanding and elucidating absorption and biodistribution of DEET and oxybenzone in vivo. The toxicological data suggested that the risk for increasing adverse effects from concurrent skin application of repellents and sunscreens would be low and marginal in healthy individuals. Nevertheless, further studies should be carried out to assess the long-term health impact of these compounds in susceptible subjects, especially at higher application doses.
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Cheney, Betty Jean. "Single Drop Microextraction: An Educational Undergraduate Laboratory Procedure Using Caffeine and DEET." Wittenberg University Honors Theses / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wuhonors1338487212.
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Menon, Kalapurakkal Sunil. "Exposure of children to deet and other topically applied insect repellents." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2535.
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Thesis (M.P.H) -- University of Maryland, College Park, 2005.Thesis research directed by: Dept. of Public and Community Health. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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SANTHANAM, ARJUN. "MATHEMATICAL MODEL TO PREDICT THE SKIN DISPOSITION OF DEET AND OTHER VOLATILE COMPOUNDS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1092343602.
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Karr, Jennifer I. "A novel encapsulation favorably modifies the skin disposition of topically-applied N,N-diethyl-3-methylbenzamide (DEET)." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353154812.
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Wang, Tao. "Evaluation of percutaneous penetration of insect repellent DEET and sunscreen oxybenzone from emulsion-based formulations." Acta Pharmaceutica Sinica B, 2014. http://hdl.handle.net/1993/23341.
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Insect repellent N,N-diethyl-m-toluamide (DEET) and sunscreen oxybenzone are commonly incorporated into commercially available consumer care products that are utilized to prevent vector-borne diseases and skin aging and damage. Semisolid emulsion-based formulation has been extensively selected for active repellent and sunscreen ingredients due to their excellent solubilizing properties for both lipophilic and hydrophilic components and satisfactory customer acceptance. Under the ideal use situation, an appropriate and elegant emulsion-based formulation can minimize transdermal absorption of DEET and oxybenzone and maximize their skin protection effect. The percutaneous penetration profiles of DEET and oxybenzone from several emulsion-based formulations were evaluated and compared by using the in vitro diffusion experiments in this thesis. Various parameters in the emulsion formulations, such as emulsion type, emulsifier, emollient, penetration enhancer, thickening agent, and thixotropic properties of the emulsions, could exert significant influence on percutaneous permeation of the active ingredients from the preparations. An emulsion-based preparation using the emulsifier, Emulium 22, possessed the relatively lower skin permeation of DEET and oxybenzone than other emulsion-based preparations; it was selected for the in vivo animal study. This emulsion-based formulation containing DEET and/or oxybenzone was topically applied to rats once daily for a 60-day period to investigate systemic concentration and tissue deposition of DEET, oxybenzone, and their respective metabolites. This formulation produced lower systemic absorption of DEET and oxybenzone than the commercially available products reported in a previous animal study. The concurrent application of DEET and oxybenzone in this study did not show synergistic enhancement between the two compounds in plasma. The percutaneous penetration profiles of DEET and oxybenzone from different semisolid emulsions in the in vitro diffusion experiment provided the important information in selecting the appropriate formulation of DEET and oxybenzone for topical application. The in vivo animal study identified pharmacokinetics and biodistribution characteristics of DEET and oxybenzone from the promising lab-developed emulsion. Studies are ongoing to further improve formulation characteristics so that this emulsion-based preparation could be used to minimize overall transdermal permeation of DEET and oxybenzone from topical skin application.
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Oliveira, Filho Jaires Gomes de. "Avaliação do papel repelente de voláteis isolados no odor de cães da raça Beagle contra o carrapato Rhipicephalus sanguineus (Acari: Ixodidae)." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4117.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Ticks are arthropods of great importance in public health, due to the transmission of many pathogens. Rhipicephalus sanguineus parasites mainly dogs. It is known that Beagle dogs are less susceptible to R. sanguineus than English Cocker Spaniel, and still have resistance patterns linked to immunity. The lower susceptibility of Beagle dogs is due to chemical compounds they produce, which act in reducing the parasitic load of R. sanguineus on these animals. Given that this research aimed to verify the chemical repellency against R. sanguineus of compounds that have been identified in the odor of resistant dogs, and synthetic repellent compounds to other tick species. For testing chemical repellency two tests were used, the Petri dish and the Y-olfactometer. Five compounds identified in Beagle odors were selected and tested: 2 - hexanone, nonane, decane, undecane and benzaldehyde, the compound of botanical origin β-citronellol and the standard repellent DEET (N,N-diethyl-3-methylbenzamide). These compounds were tested alone and also two mixtures were evaluated: benzaldehyde and 2-hexanone (1:1), and benzaldehyde, 2-hexanone and undecane (1:1:1). All these compounds were prepared in a stock solution of 7.2 % ( ≈ 0.200 mg/cm²) and two lower concentrations were also tested: 0.100 and 0.050 mg/cm². DEET was repellent in the two highest concentrations and 68.33 to 86.67% of the ticks were found in untreated areas in different time points. At the concentration of 0.050 mg/cm² ticks were distributed similarly (without significant difference) in both areas. β-citronellol was the only compound tested that was repellent at all times and concentrations tested. The percentage of ticks in untreated areas ranged from 73.33 to 93.33 %. When compared β-citronellol with DEET the first compound was more effective at repelling the adults of R. sanguineus. For benzaldehyde, 30 minutes at a concentration of 0.200 mg/cm² a percentage of 63.33 % of ticks was observed in the untreated area. Percentage of 76.67 was observed after 5 min. at a concentration of 0.050 mg/cm². 2-hexanone was repellent at 30 min. at a concentration of 0.200 mg/cm² at 10 min. at a concentration of 0.100 mg/cm² and 30 minutes at a concentration of 0.050 mg/cm². For undecane a rate of 65.00% of ticks was observed in the untreated area in one moment of testing, the highest concentration during the first 5 min. of the evaluation. Nonane and decane not were not repellent at any of the concentrations and time intervals. The blend benzaldehyde + 2-hexanone was repellent in the three highest concentrations in almost all evaluated times, including in the olfactometer testing. During the whole test this mixture showed statistical similarity when compared with DEET. The addition of undecane to this blend did not potentiate its repellent power. The main result was the finding of natural repellents in resistant dogs to the tick R. sanguineus.
Carrapatos são artrópodes de grande importância dentro da saúde pública, devido à transmissão de inúmeros patógenos. Rhipicephalus sanguineus parasita principalmente cães. Sabe-se que cães da raça Beagle são menos susceptíveis ao R. sanguineus que cães Cocker Inglês, e ainda apresentam padrões de resistência ligados a imunidade. A menor susceptibilidade de cães Beagle está ligada a compostos químicos que estes produzem, os quais atuam na diminuição da carga parasitária de R. sanguineus sobre estes animais. Sabendo-se disso com esta pesquisa objetivou-se verificar a repelência química de compostos que foram identificados no odor de cães resistentes, além de compostos sintéticos repelentes para outros carrapatos, contra o R. sanguineus. Para os testes de repelência química foram utilizados dois ensaios de repelência, o da placa de Petri e do olfatômetro em Y. Foram testados cinco compostos com provável poder repelente e identificados nos odores de Beagle (2-hexanona, nonano, decano, undecano e benzaldeído), o composto de origem botânica β-citronelol e o repelente padrão DEET (N,N-dietil-3-metilbenzamida). Além destes compostos testados isoladamente, duas misturas foram avaliadas: benzaldeído e 2 -hexanona (1:1), e benzaldeído, 2-hexanona e undecano (1:1:1) Todos estes compostos foram formulados a partir de uma solução mãe de 7,2% (≈ 0,200 mg/cm²) da qual foi obtida posteriormente outras duas concentrações (0,100 e 0,050 mg/cm²). O DEET foi repelente nas duas maiores concentrações, sendo que 68,33 a 86,67% dos carrapatos foram encontrados nas áreas não tratadas, nos diferentes tempos de observação. Na concentração de 0,050 mg/cm² os carrapatos se distribuíram similarmente (sem diferença significativa) em ambas as áreas. β-citronelol foi o único composto testado que foi repelente em todos os tempos e concentrações testados. Os percentuais de carrapatos nas áreas não tratadas variaram de 73,33 a 93,33%. Quando comparado com o DEET o β-citronelol foi mais eficiente em repelir os adultos de R. sanguineus. Para o benzaldeido, aos 30 minutos, na concentração de 0,200 mg/cm² foi observado um percentual de 63,33% de carrapatos na área não tratada. Percentual de 76,67 foi observado aos cinco minutos, na concentração de 0,050 mg/cm². A 2-hexanona foi repelente aos 30 minutos, na concentração de 0,200 mg/cm², aos 10 minutos, na concentração de 0,100 mg/cm² e aos 30 minutos, na concentração de 0,050 mg/cm². Para o undecano foi observado um percentual de 65,00 de carrapatos na área não tratada em apenas um momento dos testes, na maior concentração, durante os primeiros cinco minutos de avaliação. Nonano e decano não causaram qualquer repelência para os carrapatos testados, em qualquer uma das concentrações ou intervalos de tempo avaliados. A mistura benzaldeido + 2-hexanona foi repelente nas três maiores concentrações, em quase todos os tempos avaliados, inclusive no teste de olfatometria. Durante todo o teste esta mistura mostrou semelhança estatística quando comparada com o DEET. A adição de undecano a esta mistura não potencializou o seu poder repelente. O principal resultado obtido foi a constatação da presença de repelentes naturais em cães resistentes ao carrapato R. sanguineus.
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Martini, Gisela de Assis. "Avaliação da citotoxicidade do Dietiltoluamida (DEET) em mexilhões Perna perna (Linnaeus, 1758) irradiados e não irradiados com radiação gama de 60Co." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-20012014-134632/.
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Estudos recentes têm identificado a presença de diversos poluentes emergentes em ambientes aquáticos. A ocorrência em diferentes matrizes ambientais tem sido continuamente relatada, o que evidencia a necessidade de estudos de toxicidade. O DEET (N,N-dietil-meta-toluamida) é o princípio ativo mais utilizado em repelentes de insetos e está presente em diversas formulações comercialmente disponíveis. Além dos poluentes químicos, os organismos aquáticos estão sujeitos à exposição da radiação ionizante proveniente de fontes naturais ou em proximidades de instalações de usinas nucleares. O presente estudo avaliou a toxicidade do DEET em organismos irradiados e não irradiados com radiação gama de 60Co, e os efeitos que a radiação causa sob os lisossomos de hemócitos do mexilhão Perna perna. Para isso, foram realizados ensaios de toxicidade aguda para identificar a concentração de DEET e a dose de radiação gama passíveis de causar mortalidade, e posteriormente ensaios de citotoxicidade avaliando a estabilidade da membrana lisossômica em organismos expostos ao DEET e radiação ionizante. De acordo com os resultados obtidos nos ensaios de toxicidade aguda, a concentração de DEET que causa mortalidade em 50% dos organismos expostos (CL50) é de 114,27 mg L-1, e a dose de radiação que causa mortalidade (DL50) é de 1068 Gy. Nos os ensaios de citotoxicidade obteve-se a concentração de efeito não observado (CENO) para organismos irradiados e não irradiados de 0,0001 mg L-1 e a concentração de efeito observado (CEO) em concentrações acima desta. A CI25(72h) para organismos não irradiados foi de 0,0003 mg L-1 e a CI50(72h) foi de 0,0008 mg L-1 para organismos irradiados e não irradiados. Apesar das concentrações de efeito encontradas no presente estudo terem sido mais altas que as ambientais, estão na mesma ordem de grandeza e também deve-se levar em consideração os possíveis efeitos sinérgicos do DEET com outros contaminantes presentes em ambiente aquático.Recent studies have identified the presence of several emerging pollutants in aquatic environments. The occurrence in different environmental matrices has been continuously reported, highlighting the need for toxicity studies. The DEET (N,N-diethyl-meta-toluamide) is the active ingredient used in most insect repellents, and is present in many commercially available formulations. Apart from chemical pollutants, aquatic organisms are subject to exposure of ionizing radiation from natural sources or in the vicinity of nuclear power plants. The present study evaluated the toxicity of DEET in organisms irradiated and non-irradiated with 60Co gamma radiation, and the effects that radiation causes in lysosomes of hemocytes of Perna perna mussel. For this purpose, assays were performed to identify the acute toxicity of DEET concentration and the dose of gamma radiation able to cause mortality. Subsequently, cytotoxicity assays were carried out to assess the stability of the lysosomal membrane in organisms exposed to ionizing radiation and DEET. According to the results obtained in acute toxicity tests, the concentration of DEET that causes mortality of 50% exposed organisms (LC50) is 114,27 mg L-1, and the radiation dose that causes mortality (LD50) is 1068 Gy. In the cytotoxicity assays, the concentration of the non-observed effect (NOEC) for irradiated and non-irradiated organisms 0.0001 mg L-1 and observed effect concentration (LOEC) at concentrations above this. The IC25 (72h) for non-irradiated organisms was 0.0003 mg L-1 and IC50 (72h) was 0.0008 mg L-1 for irradiated and non-irradiated organisms. Despite of the concentrations of effect found in this study were higher than in the environment, both measurements are in the same order of magnitude and should be also take into account the possible synergistic effects of DEET with other contaminants in the aquatic environment.
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Estevam, Adriana dos Santos. "Avaliação da atividade de formulações comerciais de repelentes sobre mosquitos Aedes aegypti (Diptera - Culicidae)." Pós-Graduação em Biologia Parasitária, 2018. http://ri.ufs.br/jspui/handle/riufs/9810.
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Objectives: To evaluate the efficacy of commercially used insect repellents against Aedes
aegypti stings. Material and Methods: Was used method standard the World Health
Organization to evaluate the sensitivity of the mosquito by estimating the total protection time
(TPT) of the repellent. The test consists of application of the product and introduction of the
volunteer arm into cages containing 50 female mosquitoes, aged between five and seven days.
The initial product was 10% technical grade N, N diethylbenzamine (DEET) and four
formulations with different concentrations of DEET, OFF Family (7,125%), Baruel (9,5%),
Expert Total : 1612043 and 16144314, Super Repelex Aerosol (11%), product based on
IR3535 (Repeden Spray 12%, Jonsons Baby Lotion 12.5%), and the ICARIDINE base
(Exposis Extreme Tetra 25%), by the median of each product in 6 volunteers, being three men
and three women. Results: The OFF Family brand (DEET 7,125%), Baruel (DEET 9,5) and
analytical DEET (10%) demonstrated a median of 30 minutes, even presenting different
concentrations; Super Repelex Aerosol (DEET 11%) among the products containing DEET
was the one that presented a higher median, with a TPT of 90 minutes; Expert Total (DEET
15%) (1st batch) and Expert Total (DEET 15%) (2nd batch) are shown with medians equal
with a time of 60 minutes; Repeden Spray (IR3535 12%) and Johnsons baby (IR3535 12.5%)
presented a median TPT of 60 and 30 minutes respectively, differing only in the degree of
concentration of the active principle; Exposis Extreme (25% Icaridina) presented a median of
120 minutes, showing a superiority in relation to the other products. Conclusion: The products
had a complete protection time lower than the one specified in their labels, and may leave the
population that use them as a control measure against several unprotected diseases, requiring
a greater number of reapplications of the products.Objetivos: Avaliar a eficácia de repelentes utilizados comercialmente contra picadas de Aedes aegypti. Material e Métodos: Foi utilizado o método padrão da Organização Mundial da Saúde para avaliar a sensibilidade do mosquito através da estimativa de tempo de proteção completa (TPC) do repelente. O teste consiste na aplicação do produto e introdução do braço de voluntário em gaiolas contendo 50 mosquitos fêmeas, com idade entre cinco a sete dias. Foi avaliado inicialmente produto a base de N,N dietilbenzamina (DEET) grau técnico a 10% e quatro formulações com diferentes concentrações de DEET, OFF Family (7,125%), Baruel (9,5%), Expert Total (15%) lotes: 1612043 e 16144314, Super Repelex Aerossol (11%), produto a base de IR3535 (Repeden Spray 12%, Loção Jonsons Baby 12,5%,) e a base de ICARIDINA (Exposis Extreme Tetra 25%), e estimado o TPC pela mediana de cada produto em 6 voluntários, sendo três homens e três mulheres. Resultados: A marca OFF Family (DEET 7,125%), Baruel (DEET 9,5) e DEET analítico (10%) demostraram uma mediana de 30 minutos, mesmo apresentando diferentes concentrações; Super Repelex Aerossol (DEET a 11%), dentre os produtos contendo DEET, foi o que apresentou uma maior mediana, com TPC de 90 minutos; Expert total (DEET 15%) (1º lote) e o Expert Total (DEET 15%) (2º lote) mostram-se com medianas iguais com um tempo de 60 minutos; Repeden Spray (IR3535 12%) e Johnsons baby (IR3535 12,5%) apresentaram uma mediana com TPC de 60 e 30 minutos respectivamente, diferindo apenas no grau da concentração do princípio ativo; Exposis Extreme (Icaridina a 25%) apresentou uma mediana de 120 minutos, mostrando uma superioridade em relação aos outros produtos. Conclusão: Os produtos apresentaram tempo de proteção completa inferior a especificada em seus rótulos, podendo deixar a população que os utilizam como medida de controle contra diversas doenças desprotegida, sendo necessário maior número de reaplicações dos produtos para atingir a o período de proteção desejado.
São Cristóvão, SE
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Legeay, Samuel. "Physiopathologie de l’endothélium : Applications à l’angiogenèse induite par les répulsifs anti-moustiques à base de DEET et à la dysfonction endothéliale dans le cadre du diabète de type 1 The insect repellent N,N-diethyl-m-toluamide (DEET) induces angiogenesis via allosteric modulation of the M3 muscarinic receptor in endothelial cells." Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0068.
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L’endothélium est impliqué dans de nombreux processus physiologiques et physiopathologiques tels que les phénomènes d’inflammation, d’angiogenèse, de prolifération de cellules musculaires lisses et du métabolisme de nombreux médiateurs notamment hormonaux. Ces travaux de thèse avaient pour objectif d’étudier l’endothélium sous deux aspects pouvant conduire à des pathologies : l’angiogenèse et la dysfonction endothéliale. La première étude a permis de mettre en évidence un effet pro-angiogénique in vitro et in vivo du DEET, un répulsif anti-moustiques. Cet effet était associé à une augmentation de la production du monoxyde d’azote (NO),de la phosphorylation de la focal adhesion kinase (FAK) et de l’expression du vascular endothelium growth factor (VEGF) et conduit, in fine, à une augmentation de la croissance tumorale sur un modèle de xénogreffe de tumeur chez la souris. De plus, ces travaux ont montré que l’effet du DEET était engendré au niveau endothélial par une activité inhibitrice sur l’acétyl cholinestérase ainsi que par une modulation allostérique du récepteur muscarinique M3. La deuxième partie consistait à étudier le rôle du stress du réticulum endoplasmique et de la protein-tyrosine phosphatase 1B(PTP1B), une enzyme régulant négativement la voie de l’insuline, dans la dysfonction endothéliale induite par le diabète de type 1 (DT1). Les résultats ont permis d’identifier PTP1B comme une cible potentielle pour le traitement de la dysfonction endothéliale dans le cadre du DT1. L’ensemble de ces travaux de thèse permet une meilleure compréhension de la physiopathologie de l’endothélium et par conséquent fournit des connaissances supplémentaires pour la prise en charge de pathologies impliquant l’endothéliumThe endothelium is involved in plenty physiological and pathophysiological process as inflammation, angiogenesis, smooth muscle cell proliferation and metabolism and catabolism of mediators like hormones.The aim of this work was to study the endothelium from two ways: angiogenesis and endothelial dysfunction. Firstly, we evidenced a pro-angiogenic effect in vitro andin vivo of DEET, a mosquito repellent. This effect was associated with an increase of NO production, focal adhesion kinase (FAK) phosphorylation and vascularendothelial growth factor (VEGF) expression leading to an increase of tumor growth in a mouse-xenograft model. In addition, we showed that the effect of DEET was due to both inhibition of the endothelial acetyl cholinesterase and allosteric modulation of the muscarinic type 3 receptor(M3). Secondly, we studied the role of the endoplasmic reticulum stress and the protein-tyrosine phosphatase 1B(PTP1B) in the type 1 diabetes (T1D)-induced endothelial dysfunction. Results allowed us to identify PTP1B as a potential target for the treatment of the endothelial dysfunction in the context of T1D. All these data supply a better understanding of the pathophysiology of the endothelium and consequently provide additional information for the management of pathologies involving endothelium
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Goulu, Mathilde. "Développement d’une nouvelle stratégie de protection chimique contre les moustiques vecteurs de maladies : utilisation d’une association répulsif/insecticide afin d’optimiser l’efficacité du traitement tout en réduisant les doses utilisées." Thesis, Angers, 2015. http://www.theses.fr/2015ANGE0031/document.
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Actuellement, la plupart des textiles utilisés pour limiter les contacts avec les moustiques vecteurs de maladies sont imprégnés d’insecticides pyréthrinoïdes possédant une action insecticide et répulsive. Cependant, l’apparition de résistances au sein des populations de moustiques remet en cause cette efficacité.La nouvelle stratégie de lutte contre les moustiques s’appuie sur l’effet synergique obtenu lors d’une association de deux molécules de familles chimiques différentes à effet insecticide et répulsif. Les effets de deux répulsifs, le DEET et l’IR3535 ont été étudiés sur des cellules neurosecrétrices isolées du système nerveux central de la blatte Periplaneta americana. A l’aide de la technique d’imagerie calcique, il a été possible de montrer que ces composés induisent une augmentation dose-dépendante complexe de la concentration en calcium intracellulaire. L’utilisation d’outils pharmacologiques spécifiques a permis de caractériser les cibles et les évènements moléculaires impliqués dans ces effets. A partir de ces résultats, l’IR3535 s’est avéré être le meilleur répulsif pour une association avec un insecticide néonicotinoïde, le thiaclopride. Grâce à la technique électrophysiologique du patch-clamp adaptée sur neurones d’insecte, l’effet synergique produit par l’association IR3535/thiaclopride a été observé et le rapport de concentrations répulsif/insecticide qui donne le meilleure effet synergique sur le courant entrant induit par le thiaclopride déterminé. Des tests en cône réalisés sur moustiques in vivo ont confirmé cet effet synergique,démontrant l’intérêt de proposer l’associationIR3535/thiaclopride comme nouvelle stratégie de lutte anti-vectorielleToday, most of the textiles used to limit contact with mosquitoes are impregnated with pyrethroid insecticides having both insecticidal and repellent activities. However, the development of resistance in mosquito populations reduces their efficacy. The new strategy proposed against mosquito-transmitted diseases is based on the potential synergy observed with the combination of two different compounds with insecticidal and repellent effects. In this context, the effects of two repellents DEET and IR3535 have been studied on neurosecretory cells isolated from the central nervous system of the cockroach Periplaneta Americana. Using calcium imaging, both DEET and IR3535 induce a dose-dependent complex elevation of intracellular calcium concentration. Specific pharmacological tools have allowed to characterize the different targets together with the molecular events involved in the repellent-induced calcium rise. From these results, it has been possible to identify IR3535 as the most suitable compound to be used in association with the insecticide neonicotinoid, thiacloprid. Using the whole-cell patch-clamp technique adapted on isolated insect neurons, the synergistic effect of the IR3535/thiacloprid mixture has been observed on the thiacloprid-induced current and the most efficient ratio between repellent and insecticide has also been determined. In addition, cone tests performed on in vivo mosquitoes confirm this synergistic effect, demonstrating that IR3535/thiacloprid mixture could bean alternative strategy in the management of chemical use against resistant mosquitoes
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MARTINI, GISELA de A. "Avaliação da citotoxicidade do Dietiltoluamida (DEET) em mexilhões Perna perna (Linnaeus, 1758) irradiados e não irradiados com radiação gama de sup(60)Co." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10579.
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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Oliveira, Bianca Rodrigues de. "Desenvolvimento e avaliação de nanoemulsões com óleos de Carapa guianensis e Copaifera sp. e estudo da ação repelente frente a Aedes aegypti." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-31032009-132918/.
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As doenças transmitidas por mosquitos representam uma das maiores causas de morbidade e mortalidade em todo o mundo, principalmente em países tropicais. O uso tópico de repelentes em determinadas situações torna-se a única alternativa para evitar o ataque por estes artrópodes. Os óleos de andiroba (Carapa guianensis) e copaíba (Copaifera sp.) possuem relatos de atividade repelente de insetos, podendo representar uma alternativa segura ao uso de repelentes sintéticos que apresentam riscos de toxidade em determinados casos. O objetivo desta pesquisa foi desenvolver nanoemulsões O/A, utilizando como fase oleosa os óleos de copaíba e andiroba, e testar in vivo a atividade repelente das mesmas frente ao mosquito Aedes aegypti, realizando um estudo comparativo com repelente comercial a base de DEET. Ensaios para avaliar os parâmetros físico-quimicos envolvidos no processo de obtenção das nanoemulsões, e estudos de sua estabilidade preliminar, também foram realizados. Os resultados apontam a viabilidade do método de emulsificação utilizando baixa energia na formação de nanoemulsões. A temperatura, velocidade de agitação, ordem de adição dos componentes e quantidade de tensoativo na formulação, demonstraram ser fatores críticos no processo. Foi possível obter três nanoemulsões estáveis com tamanho de glóbulos inferior a 300nm, sendo uma com 15% de óleo de andiroba; outra contendo 10% de óleo de copaíba e a terceira associando 10% de andiroba e 5% de copaíba. No ensaio repelente utilizando voluntários humanos, foi constatado que as nanoemulsões compostas de óleo de andiroba e óleo de andiroba adicionado de óleo de copaíba são capazes de repelir mosquitos Aedes aegypti por um período de 30 minutos, sendo estes resultados estatisticamente significativos em relação ao grupo controle.Mosquito-borne diseases remain a major source of illness and death worldwide, particularly in tropical countries. Mosquito repellents may be one of the most effective tools for protecting humans from vector-borne diseases. In many circumstances, applying repellent to the skin may be the only feasible way to protect against insect bites. The oils from andiroba (Carapa guianensis seed oil) and copaíba (Copaifera oil) have been studied as possible mosquito repellents. These products can be represents a safe alternative in the use of synthetic repellent, that have toxic risks in some cases. The goals of this research were to development O/A nanoemulsion using andiroba seed oil and copaíba oil and test their repellent action in vivo against bites Aedes aegypti. This study compares the repel effectiveness of nanoemulsions developed in relation to the market product of DEET. Assays to evaluate the parameters involved physicist-chemistries in the process of attainment of the nanoemulsions, and studies of its preliminary stability, had been also carried through. The results showed viability of the emulsification method using low energy in the formation of nanoemulsions. The temperature, speed of agitation, order of addition of the components and amount of surfactant in the formulation, had demonstrated to be critical factors in the process. In this study, it was possible get three stable nanoemulsion with droplets size less than 300nm, using: 15% andiroba seed oil; 10% copaiba oil and mix of andiroba seed oil (10%) and copaíba oil (5%). The repellent test with human voluntaries proves that nanoemulsions with andiroba seed oil, and the mix of andiroba seed oil and copaiba oil, are able to repel Aedes aegypti for 30 minutes period, witch are statistic signification compared to the control group.
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Rani, Rupam. "REMOVAL OF EMERGING CONTAMINANTS FROM AQUEOUS SOLUTION BY OZONE -BASED PROCESSES." Master's thesis, Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/214782.
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Civil EngineeringM.S.Env.E.
The presence of emerging contaminants (ECs) in water and wastewater systems has become a subject of significant concern worldwide. These emerging contaminants are complex organic molecules which potentially affect human health and environment. Conventional wastewater treatment plants are unable to completely remove these contaminants from water and therefore can discharge them into environment. The need to develop effective methods for ECs removal is essential. This study assess the potential of ozone based advanced oxidation processes (AOP) to oxidize number of emerging contaminants. Different combinations of ozone with hydrogen peroxide and sodium persulfate were tested. For this study 1-4, dioxane, perfluorinated compounds (PFCs), N,N-Diethyl-metatoluamide, and three pharmaceuticals sulfamethoxazole, trimethoprim and carbamazepine have been selected. The effect of different process parameters such as chemical dosages, ozone weight percent, ozone flow rates, etc. on destruction of ECs were examined. It was observed that 1, 4-dioxane were persistent to direct ozone reaction, however were easily oxidized by hydroxyl radical. However, ozonation was solely very effective (> 99 %) in removing pharmaceuticals such as sulfamethoxaole, trimethoprim and carbamazepine. It was not very efficient for the removal of perfluorinated compound and N,N-Diethylmeta-toluamide. The operational conditions were optimized for maximum removal of every compound and their influence on the degradation process is discussed.
Temple University--Theses
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Mohamed, Aly Ahmed Abd-Ella. "ETUDE DU MODE D'ACTION NEUROTOXIQUE D'UN REPULSIF, LE DEET UTILISE SEUL ET EN ASSOCIATION AVEC UN INSECTICIDE SUR L'ACETYLCHOLINESTERASE DES DUM NEURONES D'UN INSECTE LA BLATTE PERIPLANETA AMERICANA." Phd thesis, Université d'Angers, 2011. http://tel.archives-ouvertes.fr/tel-00969250.
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Le DEET (N, N-diéthyl-m-toluamide), est connu comme le répulsif le plus utilisé au monde. Bien qu'il soit efficace contre un large groupe d'arthropodes, son mode d'action exact et sa cible moléculaire ne sont pas encore connus précisément. Grâce à l'utilisation des techniques d'électrophysiologie (patch-clamp et oil-gap), d'imagerie calcique et biochimique, nous avons étudié le mode d'action du DEET sur des cellules neurosécrétrices identifiées, les DUM neurones de la blatte Periplaneta americana. Le DEET, à forte concentration, inhibe l'activité de l'acétylcholinestérase (AChE) au niveau du DUM neurone. A faible concentration, il induit une augmentation de la concentration en calcium intracellulaire via l'activation des récepteurs cholinergiques de type muscariniques (mAChRs). Dans un deuxième temps, les interactions synergiques entre le DEET et le propoxur, un carbamate connu pour inhiber l'AChE, ont été étudiées. Les résultats ont révélé que les mAChRs, correspondent bien à une nouvelle cible potentielle pour le DEET et qu'ils sont impliqués dans l'effet synergique. Le DEET, à faible et à forte concentration, agit sur des sites allostériques positifs et négatifs des mAChRs respectivement. L'action du DEET sur le site allostérique positif des mAChRs est responsable de l'effet synergique via une augmentation de la concentration en calcium intracellulaire qui potentialise l'effet anti-AChE du propoxur. L'utilisation d'outils pharmacologiques sélectifs a permis l'identification de la voie de signalisation intracellulaire (PLC, PI-PLC, CaMKinase II, récepteurs IP3) impliquée dans l'effet synergique du propoxur. Les résultats présentés dans ce mémoire vont contribuer au développement de nouvelles stratégies basées sur l'utilisation de combinaisons d'insecticides de familles chimiques différentes afin de réduire les doses des traitements tout en augmentant l'efficacité.
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Mohamed, Aly Ahmed Abd-Ella. "Etude du mode d'action neurotoxique d'un répulsif, le Deet utilisé seul et en association avec un insecticide sur l'acetylcholinesterase des dum neurones d'un insecte la blatte periplaneta americana." Angers, 2011. http://tel.archives-ouvertes.fr/tel-00969250.
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Le DEET (N, N-diéthyl-m-toluamide), est connu comme le répulsif le plus utilisé au monde. Bien qu'il soit efficace contre un large groupe d'arthropodes, son mode d'action exact et sa cible moléculaire ne sont pas encore connus précisément. Grâce à l'utilisation des techniques d'électrophysiologie (patch-clamp et oil-gap), d'imagerie calcique et biochimique, nous avons étudié le mode d'action du DEET sur des cellules neurosécrétrices identifiées, les DUM neurones de la blatte Periplaneta americana. Le DEET, à forte concentration, inhibe l'activité de l'acétylcholinestérase (AChE) au niveau du DUM neurone. A faible concentration, il induit une augmentation de la concentration en calcium intracellulaire via l'activation des récepteurs cholinergiques de type muscariniques (mAChRs). Dans un deuxième temps, les interactions synergiques entre le DEET et le propoxur, un carbamate connu pour inhiber l'AChE, ont été étudiées. Les résultats ont révélé que les mAChRs, correspondent bien à une nouvelle cible potentielle pour le DEET et qu'ils sont impliqués dans l'effet synergique. Le DEET, à faible et à forte concentration, agit sur des sites allostériques positifs et négatifs des mAChRs respectivement. L'action du DEET sur le site allostérique positif des mAChRs est responsable de l'effet synergique via une augmentation de la concentration en calcium intracellulaire qui potentialise l'effet anti-AChE du propoxur. L'utilisation d'outils pharmacologiques sélectifs a permis l'identification de la voie de signalisation intracellulaire (PLC, PI-PLC, CaMKinase II, récepteurs IP3) impliquée dans l'effet synergique du propoxur. Les résultats présentés dans ce mémoire vont contribuer au développement de nouvelles stratégies basées sur l'utilisation de combinaisons d'insecticides de familles chimiques différentes afin de réduire les doses des traitements tout en augmentant l'efficacitéDEET (N, N-diethyl-m-toluamide), is known as the most widely used repellent in the world. Although, it is effective against a large group of arthropods, its exact mode of action and molecular target are not yet known precisely. By using electrophysiological (patch clamp and oil-gap), calcium imaging and biochemical techniques, we have studied the mode of action of DEET on neurosecretory cells identified as DUM neurons of the cockroach Periplaneta americana. DEET, at high concentrations, inhibits the DUM neuron acetylcholinesterase (AChE) activity. At low concentrations, it induces an increase in intracellular calcium concentration via the activation of muscarinic acetylcholine receptors (mAChRs). In addition, the synergistic interaction between DEET and propoxur, a carbamate insecticide known to inhibit AChE, has been studied. The results show that mAChRs, correspond to new identify targets for DEET and are involved in the synergistic effect on propoxur efficacy. We further demonstrate that the repellent DEET, used at low and high concentration, acts on positive and negative allosteric sites of mAChRs, respectively. The action of DEET on the positive mAChR allosteric site is responsible for the synergistic effect via an increase in intracellular calcium concentration, which potentiates the anti-AChE effect of propoxur. Finally, the use of selective pharmacological tools has allowed the identification of the intracellular signaling pathway (PLC, PI-PLC, CaMKinase II, IP3 receptors) involved in the synergistic effect of propoxur. The results presented in this thesis will contribute to the development of new strategies based on the use of combinations of different chemical insecticides to reduce the doses of treatment while increasing the efficiency
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Chen-Hussey, Vanessa. "A cluster-randomised trial to assess whether the insect repellent 'N,N-diethyl-m-toluamide'(DEET) can provide additional protection against clinical malaria over current best practice in Lao, PDR." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2012. http://researchonline.lshtm.ac.uk/4646547/.
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Background: Malaria remains a serious threat in the Greater Mekong Sub-region (GMS), not just from the direct impact on human health, but also from the emergence and spread of resistance to artemisinin, the last remaining effective antimalarial. Malaria control in this region is therefore a high priority on a global as well as local scale. In the southern region of the Lao People's Democratic Republic (Lao PDR) as across much of the GMS malaria vectors are found biting outdoors in the early evening before people are protected by long-lasting insecticidal nets (LLlNs). Therefore there is a need for additional malaria control tools that can protect people during these evening hours. Methods: Human landing catches in a village setting in southern Lao PDR were used to evaluate the protection from evening biting given by repellent lotions containing 10-20% N,Ndiethyl-m-toluamide (DEET). A randomised controlled trial was designed to test the effect of 15% DEET against malaria. A total of 1,597 households were recruited and randomised to either the repellent or a placebo lotion. All households were also provided with LLiNs. The acceptance and compliance with the repellent lotion was assessed through exit questionnaires and focus group discussions (FGDs). A meta-analysis was then carried out to put the results from the Lao PDR in context with other repellent trials. Findings: All DEET concentrations provided at least 96% protection from evening biting over five hours. However 15% DEET was determined to be the best choice of intervention over 10% DEET after also considering the results of other similar trials. Intention to treat analysis of the randomised controlled trial found no difference between treatment arms after accounting for gender and socio-economic status (incidence rate ratio 0.96, 95% confidence interval 0.54- 1.71, p=O.886). According to protocol analyses of participants who used the lotions over 90% of the time also found no effect from repellent use after other factors had been taken into account (incidence rate ratio 1.45, 95% confidence interval 0.53-3.99, p=0.467). The most important predictor of malaria incidence was socio-economic score which indicated that lower wealth was significantly associated with an increased malaria risk. Although the repellent was well received with over 90% of participants reporting that they liked using the lotions, compliance was still low with fewer than 60% of participants using the lotions more than 90% of the time. It emerged from FGDs that the assumption that local populations were protected from night biting if they were provided with LLiNs was not always true. Adult men and children reported spending time outdoors at night hunting and fishing. The protection from malaria by repellent use in this trial was lower than in other randomised controlled trials carried out in Bolivia, Pakistan and Tanzania. The meta-analysis found that repellent use was associated with a 33% reduction in P. falciparum incidence (95% CI 0.42-1.09, p=O.l1) and a 35% reduction in P. vivax incidence (95% CI 0.18-2.34, p=0.51), however neither figure reach significance. Interpretation: Limitations of this trial include the compliance level which was lower than in other trials. In addition the variability inherent in topical repellents may make them unsuitable for use as an intervention. The outcome of this trial shows that topical insect repellent is not a suitable wide-scale intervention against malaria and does not provide significant protection over and above LLiNs in an area of outdoor biting. However, repellents do undoubtedly reduce biting and therefore their potential to be effective intervention tools remains. Future work should concentrate on forms of repellent that can be better standardised such as impregnated clothing. If successful then further research into mosquito response to repellent is recommended including, where best to apply and the potential for the development of resistance.
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Chan, Kevin Ki Fai. "Factors influencing arbovirus transmission: vector competence and the effects of virus infection on repellent response, oxidative stress, and glutathione-S-transferase activity." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/104393.
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Zika (ZIKV), La Crosse (LACV), and Cache Valley (CVV) viruses are mosquito-vectored diseases that cause significant morbidity and mortality in humans and animals. Transmission of these viruses are dependent on numerous factors including vector competence and the effects of mosquito-virus interactions. We conducted vector competence studies of local Aedes and Culex mosquitoes for ZIKV and CVV, and found that all Aedes mosquitoes were competent for CVV and only Aedes albopictus and Aedes japonicus were competent for ZIKV. Vector competence for CVV was dose-dependent, where mosquitoes orally infected with high titers developed higher transmission rates. We also found that vector competence for ZIKV was limited by midgut and salivary gland barriers. Second, we looked at the effects of LACV and ZIKV infection on repellent response in Aedes mosquitoes and found that infected mosquitoes were refractory to low concentrations of DEET, picaridin, and PMD. Increasing concentrations of the repellents to ≥10% was able to increase percent protection (%p) against infected and uninfected mosquitoes. Lastly, we determined the effects of ZIKV and LACV infection on oxidative stress and glutathione-S-transferase (GST) activity in Aedes albopictus. Virus infection had no effect on oxidative stress, but GST activity was significantly different for mosquitoes 3-days post-exposure. We found that oxidative stress levels and GST activity had an inverse relationship for infected and uninfected mosquitoes, where oxidative stress decreased and GST activity increased over the 10-day test period. This indicates that GSTs may aid in controlling byproducts of oxidative stress. The results from this entire study identified competent vectors for emerging arboviruses and demonstrated the behavioral and physiological effects of virus infection in the mosquito vector.Doctor of Philosophy
Zika (ZIKV), La Crosse (LACV), and Cache Valley (CVV) viruses are transmitted by mosquitoes and can make humans and animals very sick. There are many biological factors that determine if a mosquito can transmit a virus and these viruses can change the biology of a mosquito. We conducted laboratory studies to see if Aedes and Culex mosquitoes can transmit ZIKV and CVV. We found that all Aedes mosquitoes were able to transmit CVV and only the Asian tiger mosquito and Asian rock pool mosquito were able to transmit ZIKV. Mosquitoes infected with high amounts of CVV developed higher transmission rates. We also found that transmission of ZIKV was limited by barriers in the mosquito midgut and salivary glands. Second, we looked at the effects of LACV and ZIKV infection on how Aedes mosquitoes respond to repellents and found that infected mosquitoes were less sensitive to low concentrations of DEET, picaridin, and PMD. Increasing concentrations of the repellents to 10% or higher was able to provide adequate protection against infected and uninfected mosquitoes. Lastly, we determined the effects of ZIKV and LACV infection on oxidative stress and glutathione-S-transferase (GST) activity in the Asian tiger mosquito. Virus infection did not change oxidative stress, but GST activity was higher in infected mosquitoes tested after 3 days after infection. We found that oxidative stress decreased and GST activity increased over the 10-day test period. This indicates that GSTs may help control damaging products from oxidative stress. The results from this entire study identified what mosquitoes were able to transmit emerging mosquito-borne viruses and demonstrated the biological effects of virus infection in the mosquitoes.
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Benzon, Sarah, and Frida Larsson. "Fiscal tools and their potential impacts on Swedish households." Thesis, KTH, Fastigheter och byggande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192166.
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Allen, James Robert. "The structure, function and specificity of the Rhodobacter sphaeroides membrane-associated chemotaxis array." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:ce7de07a-dee6-471b-9f70-22714e617693.
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Bacterial chemotaxis is the movement of bacteria towards or away from chemical stimuli in the surrounding media. Bacteria respond to chemotactic signals through chemoreceptors which bind specific ligands and transduce signals through a modified two-component system. Typical chemoreceptors bind a ligand in the periplasm and signal across the inner membrane to the cytoplasmic chemosensory array through the inner membrane. Bacterial chemoreceptors must integrate multiple signals within an array of different receptor homologues to a single output. Chemoreceptors act cooperatively to allow a rapid signal spread across the array and large signal gain. Chemoreceptors adapt to a signal by chemical modification of their cytoplasmic domains in order respond across a wide range of effector concentrations. How bacterial chemoreceptors transduce signals through the inner membrane, integrate multiple effector responses, signal cooperatively and adapt to result in a single output signal is not currently fully known. In Rhodobacter sphaeroides, additional complexity arises from the presence of multiple homologues of various chemotactic components, notably the array scaffold protein CheW. Decoding this signalling mechanism and heterogeneity involved in this system is important in decoding the action of a biological system, with implications for biotechnology and synthetic biology. This study used the two model systems Escherichia coli and R. sphaeroides to analyse the mechanism of signalling through bacterial chemoreceptors. Rational design of activity-shifting chemoreceptor mutations was undertaken and these variants were analysed in phenotypic and fluorescence localisation studies. Molecular-dynamics simulations showed an increase in flexibility of chemoreceptors corresponds to a decrease in kinase output activity, which was determined by the computational tracking of bacteria free-swimming in media. Fluorescence recovery after photobleaching was used to show that this increase in flexibility results in a decrease in binding of receptors to their array scaffold proteins. A two-hybrid screen also suggested that inter-receptor affinity is also likely to decrease. These results show that signalling through chemoreceptors is likely through a mechanism involving the selective flexibility of chemoreceptor cytoplasmic domains. Analysis of R. sphaeroides chemoreceptors and CheW scaffold proteins in E. coli showed that it should be possible to design, from the bottom-up, a functional bacterial chemotaxis system in order to analyse individual protein specificity. Expression of R. sphaeroides MCPs in this E. coli system show the reconstitution of a chemotactic array, but not one capable of signalling specifically to proposed attractants. Results gained from this system suggest the R. sphaeroides CheW proteins are not homologous and their differential binding affinities may allow array activity 'fine-tuning'.
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Ch��zaro, Arellano Eva Hortensia. "Integraci��n del Modelo Pedag��gico basado en la Sabidur��a Nativa. Cerrando el c��rculo del aprendizaje." Thesis, Universidad de las Am��ricas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/det/chazaro_a_eh/.
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Este estudio de investigaci��n es una contribuci��n a la sistematizaci��n del paradigma nativo como base del conocimiento. Parte del riesgo que se observa en la construcci��n de propuestas interculturales como atenci��n a la diversidad cultural, que todav��a conservan un matiz epistemol��gico occidentalizado. Se da respuesta a la pregunta focal ��C��mo se aprende desde el conocimiento nativoα Mediante una metodolog��a cualitativa impregnada de la incipiente metodolog��a nativa en investigaci��n, se ofrece como objetivo alcanzado la integraci��n del Modelo Pedag��gico Nativo, una tendencia hacia cerrar el c��rculo del aprendizaje. A trav��s de un an��lisis documental profundo, observaci��n participante, grupos de conversaci��n, relatos familiares y entrevistas semiestructuradas; se realiz�� un an��lisis descrito con detalle que evidencia la Sabidur��a Nativa como medio de vida para formar seres humanos ��ntegros en la comunidad y en el Espacio Territorial. Abstract This research is a contribution to the sistematization of the native paradigm as base of knowledge. Consider the problem that is possible to see in the construction of intercultural procces for attend cultural diversity, but with an occidental epistemological base yet(cont.) Answer the focal question ��How native people learnα With a qualitative methodology and elements from a native methodology for research, the objective is the integration of the Native Pedagogical Model, for close the learning circle. On this study was used methods as deep documental analysis, participant observation, talking circles, familiar stories and interviews. The researcher did an analysis described on details that evidence the Native Wisdom as lifestyle for form whole human beings in the community and Territorial Space..
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Yzasmendi, Arellano Guillermo Rodolfo. "Evaluaci��n por competencias en el razonamiento l��gico-matem��tico y en el cambio de actitud hacia la ciencia." Thesis, Universidad de las Am��ricas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/det/yzasmendi_a_gr/.
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Luna, Gijón Gerardo. "Desarrollo de un modelo instruccional para diseñar materiales digitales de aprendizaje en el área de medicina." Thesis, Universidad de las Américas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/det/luna_g_g/.
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Uno de los retos que existen actualmente en la educación en las ciencias de la salud es el no tener en claro para qué, cómo y cuándo nos sirven los medios digitales como un apoyo en la educación de los estudiantes del periodo de preclínica. Existe una falta de modelos instruccionales dirigidos a profesores del periodo de preclínica de las universidades poblanas, que sean específicos para desarrollar objetos de aprendizaje médicos, y que centren su atención en los procesos de interacción entre las personas y aquella información que producen.
Esto da pie y provee de la oportunidad para un proyecto que ayude a innovar y modernizar el alto nivel de preparación, que se exige tengan los futuros practicantes de la medicina en el estado de Puebla. Apoyando a los profesores universitarios, se espera que el impacto y enriquecimiento en su práctica docente repercuta en el aprendizaje de los estudiantes, que estarán mejor capacitados para lidiar con las complejidades de su área, y además contarán con una formación humana de alta calidad.
El objetivo de la investigación fue desarrollar un modelo instruccional para diseñar materiales educativos digitales que apoye el Razonamiento Clínico en la enseñanza preclínica y que aprovechara las aportaciones que por separado han hecho diversas áreas del diseño, como son el campo del diseño instruccional y del diseño de la información visual.
Para la validación del modelo se utilizó la técnica Delphi. El primer paso fue buscar un panel de profesores expertos, que abarca dos facultades de medicina. A cada uno se le pidió que analizara e hiciera recomendaciones con base en (1) efectividad de las etapas propuestas, (2) adecuación para las condiciones y necesidades de los profesores médicos, (3) tiempo y facilidad de ejecución del modelo. Además se recurrió a la opinión de expertos en educación y en diseño.
La retroalimentación obtenida fue positiva, con un alto grado de aceptación del modelo por parte de los expertos. Las etapas y pasos del modelo propuesto son adecuados y valiosos; además se ha realizado una versión condensada del modelo para mejorar tiempo de ejecución y facilidad, para aquellos profesores dedicados a la enseñanza de tiempo parcial en las instituciones.
Este estudio provee evidencia de la viabilidad para apoyar a los profesores médicos de las distintas universidades del estado de Puebla, para diseñar materiales digitales educativos mediante un modelo instruccional que promueve el Razonamiento Clínico mediante el uso de casos clínicos, en los estudiantes de medicina durante la preclínica.
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Cuanalo, Gómez Miguel Angel. "Una aproximación a los esquemas de pensamiento holístico y neoliberal de un grupo de estudiantes de educación superior: un estudio exploratorio." Thesis, Universidad de las Américas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/det/cuanalo_g_ma/.
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El presente estudio es una exploración de la cercanía de los esquemas de pensamientos de
una muestra de estudiantes de distintas licenciaturas pertenecientes a una institución de
educación superior privada hacia ya sea un marco holístico de pensamiento o de forma
contraria al marco holístico neoliberal. Esto con el objetivo de responder a la situación
global de desigualdad, pobreza y sobre explotación del ecosistema, reportada por la PNUD
(2010) y otros organismos internacionales, desde un paradigma educativo holístico que
considere los fines de la educación respecto a totalidades más amplias como la sociedad o
el ecosistema para ir más allá de enfoques utilitarios y funcionalistas que responden
únicamente a los sistemas de control definidos por De Miguel (1993) o de autoridad de
Strike (1997) como mercado, gobierno y academia. En este trabajo se proponen los
supuestos de totalidad, relacionalidad y transformación de dicho paradigma a partir de los
cuales son explorados los esquemas de pensamiento de los estudiantes con preguntas
previamente validadas en torno a temas alusivos al desarrollo individual, social, natural y
problemáticas vigentes como al pobreza para encontrar elementos que permitan ubicarlos
en su cercanía hacia el holismo o el neoliberalismo.
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Huang, Ruobing. "Delving deep into fetal neurosonography : an image analysis approach." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:63aec035-dee2-40d4-9e00-ee1674a52494.
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Ultrasound screening has been used for decades as the main modality to examine fetal brain development and to diagnose possible anomalies. However, basic clinical ultrasound examination of the fetal head is limited to axial planes of the brain and linear measurements which may have restrained its potential and efficacy. The recent introduction of three-dimensional (3D) ultrasound provides the opportunity to navigate to different anatomical planes and to evaluate structures in 3D within the developing brain. Regardless of acquisition methods, interpreting 2D/3D ultrasound fetal brain images require considerable skill and time. In this thesis, a series of automatic image analysis algorithms are proposed that exploit the rich sonographic patterns captured by the scans and help to simplify clinical examination. The original contributions include: 1. An original skull detection method for 3D ultrasound images, which achieves mean accuracy of 2.2 ± 1.6 mm compared to the ground truth (GT). In addition, the algorithm is utilised for accurate automated measurement of essential biometry in standard examinations: biparietal diameter (mean accuracy: 2.1 ± 1.4 mm) and head circumference (mean accuracy: 4.5 ± 3.7 mm). 2. A plane detection algorithm. It automatically extracts mid-sagittal plane that provides visualization of midline structures, which are crucial to assess central nervous system malformations. The automated planes are in accordance with manual ones (within 3.0 ± 3.5°). 3. A general segmentation framework for delineating fetal brain structures in 2D images. The automatically generated predictions are found to be agreed with the manual delineations (mean dice-similarity coefficient: 0.79 ± 0.07). As a by-product, the algorithm generated automated biometry. The results might be further utilized for morphological evaluation in future research. 4. An efficient localization model that is able to pinpoint the 3D locations of five key brain structures that are examined in a routine clinical examination. The predictions correlate with the ground truth: the average centre deviation is 1.8 ± 1.4 mm, and the size difference between them is 1.9 ± 1.5 mm. The application of this model may greatly reduce the time required for routine examination in clinical practice. 5. A 3D affine registration pipeline. Leveraging the power of convolutional neural networks, the model takes raw 3D brain images as input and geometrically transforms fetal brains into a unified coordinate system (proposed as a Fetal Brain Talairach system). The integration of these algorithms into computer-assisted analysis tools may greatly reduce the time and effort to evaluate 3D fetal neurosonography for clinicians. Furthermore, they will assist understanding of fetal brain maturation by distilling 2D/3D information directly from the uterus.
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Cusack, Martin. "The role of DNA methylation on transcription factor occupancy and transcriptional activity." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:7d0b7fe7-dee1-433f-8656-c9ee2a216d48.
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DNA methylation is an epigenetic mark that is deposited throughout the genome of mammals and plays an important role in the maintenance of transcriptionally repressive states across cell divisions. There are two major mechanisms by which DNA methylation has been proposed to act: one involves the recognition of the mark by protein complexes containing histone deacetylases (HDACs) that can remodel the local chromatin. Alternatively, methylation has been suggested to directly affect the interaction between transcription factors and their cognate binding sequence. The aim of this research was to determine the contributions of these two mechanisms in cells. The importance of HDAC activity in mediating DNA methylation-dependent transcriptional repression was assessed by comparing the genes and retrotransposons that are upregulated in response to DNA methylation loss or the disruption of HDAC activity. To this purpose, we performed whole-genome transcriptional analysis in wild type and DNA methylation-deficient mouse embryonic stem cells (DNMT.TKO mESCs) in the presence and absence of the HDAC inhibitor trichostatin A. Our data suggests that there are few genes whose repression is solely dependent on the recruitment of HDACs by DNA methylation in mESCs. Rather it appears that DNA methylation and HDAC-mediated silencing represent two independent layers of repression that converge at certain transcriptional elements. To investigate the contribution of DNA methylation on the genome-wide occupancy of transcription factors, we compared the global chromatin accessibility landscape and the binding profile of candidate transcription factors in the absence or presence of DNA methylation. We found that loss of DNA methylation associates with localised gains in accessibility, some of which can be linked to the novel binding of transcription factors such as GABPA, MAX, NRF1 and YY1. Altogether, our results present new insights into the interplay between DNA methylation and histone deacetylation and their impact on the localisation of transcription factors from different families.
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Seraku, Tohru. "Clefts, relatives, and language dynamics : the case of Japanese." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:0448acc3-dee6-4b1b-9020-95fd84895f24.
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The goal of this thesis is to develop a grammar model of Japanese within the framework of Dynamic Syntax (Cann et al. 2005, Kempson et al. 2001), with special reference to constructions that involve the nominaliser no: clefts and certain kinds of relatives. The more general theoretical position which it aims to defend is that an account of these constructions in terms of ‘language dynamics’ is preferable to other ‘static’ approaches currently available. What is here meant by ‘language dynamics,’ in a nutshell, is the time-linear processing of a string and attendant growth of an interpretation. First, I shall motivate, and articulate, an integrated account of the two types of no- nominalisation. These two classes are uniformly modelled as an outcome of incremental semantic-tree growth. The analysis is corroborated by naturally-occurring data extracted from the Corpus of Spontaneous Japanese (CSJ). Moreover, novel data with regard to coordination are accounted for without losing uniformity. Second, the composite entry of no and the topic marker wa handles the two types of clefts uniformly. This account fits well with the CSJ findings. New data concerning case-marking of foci are explained in terms of whether an unfixed relation in a semantic tree is resolvable in incremental processing. The account also solves the island-puzzle without abandoning uniformity. As a further confirmation, the analysis is extendable to stripping/sluicing, making some novel predictions on case-marking patterns. Third, the entry of no characterises free relatives and change relatives in a unitary manner. Furthermore, the composite entry of no and a case particle predicts a vast range of properties of head-internal relatives, including new data (e.g., negation in the relative clause, locality restriction on the Relevancy Condition). In sum, the thesis presents a realistic, integrated, and empirically preferable model of Japanese. Some consequences stand out. The various new data reported are beneficial theory-neutrally. Formal aspects of Dynamic Syntax are advanced. The insights brought by a language dynamics account challenge the standard, static conception of grammar.
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Barty, Karin, and edu au jillj@deakin edu au mikewood@deakin edu au kimg@deakin. "Students' experiences of e-learning at school." Deakin University. School of Education, 2001. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20040614.145900.
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The dissertation describes the experiences of senior secondary students taking an online course for the first time to further their language education. The experiences are presented from the perspective of students, of supervising teachers and the 'virtual' teacher. Issues of importance with younger learners are identified and discussed and guidelines for the conduct of online courses at school level developed. It is proposed that online courses may have a worthwhile place in school education if specific learning needs can be met using this medium.
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Ejigayehu, Dereje Abere. "The effect of external debt on Economic Growth : A panel data analysis on the relationship between external debt and economic growth." Thesis, Södertörns högskola, Institutionen för samhällsvetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-20166.
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The impact of external debt on economic growth is a debatable issue between scholars since the onset of the debt crisis in 1980’s. This thesis examines whether external debt affects the economic growth of selected heavily indebted poor African countries through the debt overhang and debt crowding out effect. This is carried out by using data for eight heavily indebted poor African countries between 1991 to 2010.The result from estimation shows that external debt affects economic growth by the debt crowding out effect rather than debt overhang. Moreover, in an attempt to mark out debt servicing history, the thesis found the selected countries are not paying (servicing) more than 95% of their accumulated debt.
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Hervert, John Joseph. "Mule deer use of water developments in Arizona." Thesis, The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_270_sip1_w.pdf&type=application/pdf.
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Dan-Jumbo, F. G. "Material and structural properties of a novel Aer-Tech material." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/699ca3a1-deec-4549-b907-0e06bcdad83f/1.
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This study critically investigates the material and structural behaviour of Aer-Tech material. Aer- Tech material is composed of 10% by volume of foam mechanically entrapped in a plastic mortar. The research study showed that the density of the material mix controls all other properties such as fresh state properties, mechanical properties, functional properties and acoustic properties. Appreciably, the research had confirmed that Aer-Tech material despite being classified as a light weight material had given high compressive strength of about 33.91N/mm2. The compressive strength characteristics of Aer-Tech material make the material a potential cost effective construction material, comparable to conventional concrete. The material also showed through this study that it is a structural effective material with its singly reinforced beam giving ultimate moment of about 38.7KN. In addition, the Aer-Tech material is seen as a very good ductile material since, the singly reinforced beam in tension showed visible signs of diagonal vertical cracks long before impending rapture. Consequently, the SEM test and the neural network model predictions, carried out had showed how billions of closely tight air cells are evenly distributed within the Aer-Tech void system as well as the close prediction of NN model for compressive strength and density are same with the experimental results of compressive strength and density. The result shows that the Aer-Tech NN-model can simulate inputs data and predicts their corresponding output data.
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Tanimura, Joseph Kiyoshi. "Taxes, financial distress and capital structure in the United States and Japan." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8745.
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Ebersole, Regina L. "Efficacy of a controlled hunt for managing white-tailed deer on Fair Hill Natural Resource Management Area, Cecil County, Maryland." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 66 p, 2007. http://proquest.umi.com/pqdweb?did=1253509781&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Merkt, Juan R. "Social structure of Andean deer (Hippocamelus antisensis) in southern Peru." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24864.
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The taruca (Hippocamelus antisensis) is the only deer species found permanently in rugged mountainous habitat above the tree line. I studied the social organization of this deer in relation to its reproductive cycle and habitat use in the high Andes of southern Peru. Tarucas bred seasonally. Most fawns were observed towards the end of the rainy season between February and April. Mating was most common in June, during the dry season, and antler-shedding in males occurred in September/October, at the onset of the rainy season. The deer lived in social groups and, unlike most seasonally breeding cervids, formed large mixed-sex groups nearly all year. During the birth season, however, all pregnant females segregated to form female associations. At this time, adult males were found equally in mixed-sex groups or in small all-male groups. These groups differed in their habitat use. Female groups used areas of higher elevation, steeper slopes, and greater rock-cover than either male or mixed-sex groups. I suggest that selection of more rugged and concealed habitats by lactating females is primarily an antipredator strategy to reduce risk of predation on fawns. Tarucas are compared with other social Cervidae and with their ecological counterpart: the mountain Caprinae. The social structure of Hippocamelus resembles that of wild goats (Capra spp) and other Caprinae of similar ecology but it differs from that of wild sheep (Ovis spp).Science, Faculty of
Zoology, Department of
Graduate
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Straube, Nicolas. "Deep divergence." Diss., Ludwig-Maximilians-Universität München, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-138186.
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Joseph, Caberbe. "DEEP WITHIN." Master's thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2794.
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As a contemporary photographer, I focus most on light and color to bring out the uniqueness of my images. Photography is about lighting and I manipulate lights to raise questions in my viewers. Manipulating light is my way of being curious about how it may change mood physically and emotionally. Inspired by classical paintings, I have developed a body of photographs that can be admired by anyone. Although the main focus of my work is light and color, this body of work is also intended to empower those with little confidence in themselves and those who have been rejected, abused, or mistrusted.M.F.A.
Department of Art
Arts and Humanities
Studio Art and the Computer MFA
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Peterson, Grant. "Deep time /." abstract, 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1455664.
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Thesis (M.A.)--University of Nevada, Reno, 2008."May, 2008." Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2009]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.
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Traxl, Dominik. "Deep graphs." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17785.
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Netzwerk Theorie hat sich als besonders zweckdienlich in der Darstellung von Systemen herausgestellt. Jedoch fehlen in der Netzwerkdarstellung von Systemen noch immer essentielle Bausteine um diese generell zur Datenanalyse heranzuziehen zu können. Allen voran fehlt es an einer expliziten Assoziation von Informationen mit den Knoten und Kanten eines Netzwerks und einer schlüssigen Darstellung von Gruppen von Knoten und deren Relationen auf verschiedenen Skalen. Das Hauptaugenmerk dieser Dissertation ist der Einbindung dieser Bausteine in eine verallgemeinerte Rahmenstruktur gewidmet. Diese Rahmenstruktur - Deep Graphs - ist in der Lage als Bindeglied zwischen einer vereinheitlichten und generalisierten Netzwerkdarstellung von Systemen und den Methoden der Statistik und des maschinellen Lernens zu fungieren (Software: https://github.com/deepgraph/deepgraph). Anwendungen meiner Rahmenstruktur werden dargestellt. Ich konstruiere einen Regenfall Deep Graph und analysiere raumzeitliche Extrem-Regenfallcluster. Auf Grundlage dieses Graphs liefere ich einen statistischen Beleg, dass die Größenverteilung dieser Cluster einem exponentiell gedämpften Potenzgesetz folgt. Mit Hilfe eines generativen Sturm-Modells zeige ich, dass die exponentielle Dämpfung der beobachteten Größenverteilung durch das Vorhandensein von Landmasse auf unserem Planeten zustande kommen könnte. Dann verknüpfe ich zwei hochauflösende Satelliten-Produkte um raumzeitliche Cluster von Feuer-betroffenen Gebieten im brasilianischen Amazonas zu identifizieren und deren Brandeigenschaften zu charakterisieren. Zuletzt untersuche ich den Einfluss von weißem Rauschen und der globalen Kopplungsstärke auf die maximale Synchronisierbarkeit von Oszillatoren-Netzwerken für eine Vielzahl von Oszillatoren-Modellen, welche durch ein breites Spektrum an Netzwerktopologien gekoppelt sind. Ich finde ein allgemeingültiges sigmoidales Skalierungsverhalten, und validiere dieses mit einem geeignetem Regressionsmodell.Network theory has proven to be a powerful instrument in the representation of complex systems. Yet, even in its latest and most general form (i.e., multilayer networks), it is still lacking essential qualities to serve as a general data analysis framework. These include, most importantly, an explicit association of information with the nodes and edges of a network, and a conclusive representation of groups of nodes and their respective interrelations on different scales. The implementation of these qualities into a generalized framework is the primary contribution of this dissertation. By doing so, I show how my framework - deep graphs - is capable of acting as a go-between, joining a unified and generalized network representation of systems with the tools and methods developed in statistics and machine learning. A software package accompanies this dissertation, see https://github.com/deepgraph/deepgraph. A number of applications of my framework are demonstrated. I construct a rainfall deep graph and conduct an analysis of spatio-temporal extreme rainfall clusters. Based on the constructed deep graph, I provide statistical evidence that the size distribution of these clusters is best approximated by an exponentially truncated powerlaw. By means of a generative storm-track model, I argue that the exponential truncation of the observed distribution could be caused by the presence of land masses. Then, I combine two high-resolution satellite products to identify spatio-temporal clusters of fire-affected areas in the Brazilian Amazon and characterize their land use specific burning conditions. Finally, I investigate the effects of white noise and global coupling strength on the maximum degree of synchronization for a variety of oscillator models coupled according to a broad spectrum of network topologies. I find a general sigmoidal scaling and validate it with a suitable regression model.
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Ferreyros, Avila Alvaro Marcell, Ochoa Raúl Martín Landa, and Montenegro Janeth Marleny Sotil. "Móvil Dent." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/625347.
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El presente proyecto está referido a un servicio odontológico móvil y ofrece evidencia sólida sobre la viabilidad de su puesta en marcha a partir de una investigación realizada en la zona 7 de Lima Metropolitana; la misma que dio como resultado la presencia de una demanda latente y aún insatisfecha en relación a este tipo de servicio. Hoy más que nunca existe una gran preocupación por el cuidado de la sonrisa y como consumidores estamos cada vez más acostumbrados a obtener servicios y productos con el menor esfuerzo posible. Es así que este servicio odontológico a móvil está orientado a satisfacer una expectativa básica del consumidor actual en relación a la conveniencia y proximidad que espera de todo tipo de servicio y/o producto.
Para su ejecución este proyecto requerirá de una inversión inicial total de S/ 1,619,862. Suma que será financiada en un 40% con un préstamo de un inversionista y el 60% restante con aporte de tres accionistas, quienes esperan recuperar su inversión al término del primer año de operaciones.The present project refers to a mobile dental service and offers solid evidence on the feasibility of its implementation based on an investigation carried out in zone 7 of Metropolitan Lima; the same that resulted in the presence of a latent and still unsatisfied demand in relation to this type of service. Nowadays there is a great concern about the care of the smile and as consumers we are increasingly accustomed to obtain services and products with the least possible effort. For this reason, this mobile dental service is aimed at satisfying a basic expectation of the current consumer in relation to the convenience and proximity expected from all types of services and/or products. For its execution this project will require a total initial investment of S/ 1,619,862. Amount that will be financed in 40% with a investor loan and 60% with the contribution of three shareholders, who expect to recover their investment at the end of the first year of operations.
Trabajo de investigación
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Jönsson, Jennifer Annie Patricia. "Deep Impression." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-22025.
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The scope of this thesis is to reveal the hidden dimensions of fashion. With the aim to stress the worth of participation and the individual experience of fashion. This work is questioning what we see, and later what is actually there. Through a thorough investigation of the knit technique the relationship of loop and thread (pause and activity) is the focus of this paper. Enhancing the significant qualities of the knitted technique, where material and shape is born simultaneously, the result presented holds a variety of results. With the aim to discuss multiple dimensions this knit investigation is presented in a fashion context. Styled with technical sportswear this work is challenging knitwear -as well as sportswear. By clashing sports connotated materials with the knitted wool, both fields are expanded and new options and expression are presented. The motive of this investigation is to further state the worth of fashion. To create a space for the experience of fashion, stating the various result that is not depending on the presentation on body. This work questions the pre-set truths and conventions of what fashion could be, and our ability to judge what is presented for us.
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Wood, Rebecca. "Deep Surface." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1427899904.
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Peralta, Yaddyra. "Deep Waters." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/622.
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The purpose of this creative thesis was to explore the state of exile via the use of the contemporary lyric poem. Written primarily in free verse, with some poems written in the traditional forms of the sonnet, haiku and senryu, the thesis explored exile and its variant themes of colonization, assimilation, familial history, cultural and personal myth. The result was the discovery that the lyric poem is an ideal, productive and fluid medium through which a poet can consider and encounter the liminality of exile identity.
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Hu, Qinglin. "Temporal variation and inter-relationship of movement and resource selection of red deer (Cervus elaphus) with respect to climate : a case study : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science (Environmental Science) at the University of Canterbury /." Thesis, University of Canterbury. Environmental Science, 2006. http://hdl.handle.net/10092/1299.
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Red deer (Cervus elaphus) is one of at least 31 herbivorous exotic mammals existing in New Zealand. All of these species have the potential to affect environmentral and production values. Reducing their impacts on their values, strengthening effective managements are important issues to a variety of agencies within New Zealand including the Department of Conservation (DOC), Ministry of Agriculture and Forestry (MAF), local and regional governments. This research studied animal movement pattern and habitat use of 2 GPScollared red deer in the Canterbury high country and found (1) deer movement was affected by climatic variables such as rainfall and temperature, which had positive or negative effect on it, and had seasonal variation; (2) deer had dominant landcover use categories, depending on climate, season, and individual characteristics (3) deer had different movement patterns in terms of hourly distances. The purpose of the study is to draw accurate inferences from spatially explicit data for biosecurity managers and policy-makers through: (1) using global positioning system (GPS) as a tool to elucidate the application of GPS on red deer in wildlife management; (2) Animal Movement Analysis Arc View® 3.2 Extension under Arc View® Geographic Information System (GIS); (3) Animal movement analysis which used Generalized Additive Models (GAMs) to show how the movement of red deer was affected by different periods of time, seasons months and climatic variables (for example, rainfall and temperature).
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Holtfreter, Robert W. Ditchkoff Stephen S. "Spatial ecology of male white-tailed deer in the Crosstimbers and Prairies ecoregion." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Forestry_and_Wildlife_Sciences/Thesis/Holtfreter_Robert_20.pdf.
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Lehasa, Mecha. "Determinants of sovereign borrowing choices in Sub-Saharan Africa." Master's thesis, Faculty of Commerce, 2020. http://hdl.handle.net/11427/33759.
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There is a growing and legitimate concern about sovereign debt increasing to unsustainable levels among the Sub-Saharan African (SSA) countries. Understanding the determinants of external debt to these countries influenced the direction of this study. The existing literature that was examined shed light mostly on the qualitative determinants of sovereign borrowing. In addition to existing empirical literature, there is a complimentary need to examine further the quantitative determinants of external debt. The researcher seeks to establish the extent to which the cost of borrowing (proxied by interest rate) explains the changes in the borrowing behaviour (proxied by external debt) among SSA countries. To achieve this objective, data from 36 SSA countries for the period 2009–2017 was used. The data were collected from International Debt Statistics compiled by the World Bank. External debt has been regressed against interest rate and other predictor variables. Hausman tests, robustness tests and collinearity tests were carried out to ascertain the validity of results. Interest rate is found to have a positive determining impact on external debt for all SSA countries aggregated: SSA countries excluding South Africa (SA); SSA excluding Nigeria; SSA excluding Nigeria and SA; SSA excluding debt-distressed countries, middle income and oilexporting countries. It does not have predictive power over changes in external debt for SSA excluding countries at high risk of distress; countries with low to moderate risk of distress; heavily indebted poor countries (HIPC) initiative post-implementation recipient countries; low income, other resource intensive and non-resource-intensive countries. External debt is also found to respond to changes in: gross national income (GNI); exports-to-imports ratio; primary income on foreign direct investment (FDI); reserves-to-imports ratio; FDI-to-GNI ratio; debt service-to-GNI ratio; interest arrears on long-term debt; short-term-to-total-debt ratio; and reserves-to-debt ratio for different country groupings. Different country groupings are found to have unique combinations of external debt determinants.
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Flesch, Jason Stefan. "Nutritional requirements of pregnant and lactating fallow deer (Dama dama) /." View thesis View thesis View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030506.152207/index.html.
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Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2001.A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy, University of Western Sydney, Hawkesbury, Faculty of Environmental Management and Agriculture. Bibliography : leaves 252-280.
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Masoga, Mamokgaetji Marius. "The impact of public debt on economic growth in South Africa : a cointegration approach." Thesis, University of Limpopo, 2018. http://hdl.handle.net/10386/2421.
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Thesis (M.Com (Economics)) --University of Limpopo, 2018The burden of public debt is an economic issue, dominating debates in different sectors of our society. The post financial crisis era has been marked with an increasing level of public debt at international, national and sub-national level. The study investigates if public debt can affect economic growth in South Africa, for the period 1995 to 2016. The results for Johansen test of cointegration signposted the existence of cointegration among variables observed in this study. The trace statistic and max-eigen value complimented each other to confirm the cointegration, thus, showing a long run relationship. Furthermore, the Vector Error Correction Model (VECM) is applied to achieve the objectives of the study, complemented by other econometric tests such as, Granger causality, impulse response function and variance decomposition. The VECM results revealed the existence of a short run relationship between public debt and economic growth. Granger causality results have shown that public debt can Granger cause economic growth, and there is bi-direction relationship between the two variables. The results for Variance Decomposition indicate that, a shock to public debt causes 1.509115 % fluctuation in economic growth in the second quarter. In the fourth quarter, a shock to public debt account for 16.39628 % fluctuations in economic growth. This shows that, as time goes on, a shock to public debt account for a high percent of fluctuation in economic growth. The Impulse Response Function has shown that, the period of ten quarters marks a negative response of economic growth to public debt. Thus, one standard deviation shock in public debt will inversely affect economic growth. The diagnostic tests such as serial correlation and heteroskedasticity bode well for the model because, neither serial correlation nor heteroskedasticity has been found. Moreover, the model has shown that the residuals are normally distributed, and also the stability of the model has been confirmed. The study recommends that, since South Africa is a capital scarce country, it is encouraged to borrow so that there is an increase in the accumulation of capital. However, the later stage of borrowing marked with high debt will lead to subdued economic growth.
SETA
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Flesch, Jason S., University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "Nutritional requirements of pregnant and lactating pregnant and lactating fallow deer (Dama dama)." THESIS_CSTE_EAG_Flesch_J.xml, 2000. http://handle.uws.edu.au:8081/1959.7/562.
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This thesis describes a number of experiments undertaken to assess the nutritional requirements of pregnant and lactating fallow does with the aim of enhancing production and Quality Assurance in the Australian Deer Industry.Areas of study include determination of metabolisable energy intake of farmed fallow deer does of two genotypes throughout pregnancy and lactation, metabolisable energy intake of fallow deer fawns from 12 to 20 weeks of age and the effects of restricted maternal nutrition on foetal and placental development at different stages of gestation.In conjunction with nutritional adequacy, a body condition scoring system based on ante-mortem and post-mortem descriptors was developed for fallow deer. The results of this research make possible the precise strategic feeding of fallow deer breeding stock, which should lead to more consistent reproductive performance and higher quality slaughter animals. Furthermore, use of strategic feeding in conjunction with BCS systems will lead to better resource management and profitability, as farmers consistently produce animals to specificationDoctor of Philosophy (PhD)
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Mårtensson, Sandra, and Amanda Lenander. "Anmälningsplikten i förskolan- "Det behöver inte vara det stora, det kan vara det lilla!"." Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-29245.
Full textAbstract:
We wanted to examine the knowledge preschool teachers have about the mandatory reporting when children are being maltreated. We have used the Attachment theory and the Communication theory in our study to help us analyse the results. Qualitative method was used in our study made with interviews from a couple of preschool teachers of their knowledge about the mandatory reporting about maltreatment of children. Some of these answers may explain why preschool teachers reports the least amount of the cases brought to attention among other professions such as police, teachers, nurses etc. Some of the results were; they already had a good relation to the children´s parents and therefore were split in loyalty, some of the preschool teachers have had a bad experience before with threatening parents and let it influence their decision to report, others have said that both families and the preschool teachers lived near the preschool which made everything more difficult, even so in a smaller town, where everyone knows each other. Of course, this is only a couple of preschool teacher´s experiences and perceptions about the mandatory reporting about maltreatment of children, and therefore do not represent all preschool teachers in Sweden.