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Attwell, Arthur. "Simple Organisms." Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/7673.
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Золотова, Світлана Григорівна, Светлана Григорьевна Золотова, Svitlana Hryhorivna Zolotova, and I. Yu Matyushenko. "Genetically modified organisms." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/13467.
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Núñez, Marcé Mireia. "Emerging organic contaminants in aquatic organisms." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/456825.
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Aquesta Tesi Doctoral se centra en el desenvolupament de nous mètodes analítics per determinar diferents contaminants orgànics emergents, com ara productes farmacèutics de consum generalitzat, els medis iodat de contrast per a raigs-X (un altre grup de productes farmacèutics emprats en la medicina de diagnòstic), i un grup d'edulcorants d'alta intensitat en organismes aquàtics. Dues tècniques d'extracció (extracció mitjançant líquids pressuritzats i QuEChERS) van ser avaluades per extreure els compostos seleccionats i diferents neteges també van ser provades. La determinació es va realitzar mitjançant cromatografia de líquids acoblada a espectrometria de masses.D'altra banda, també es va dur a terme un estudi ecotoxicològic en l'espècie Gammarus pulex, on s' avaluà la toxicitat del triclosan en aquesta espècie i, a més a més, es van estudiar poblacions procedents de diferents ambients amb diferents graus de contaminació per determinar si la seva resistència era similar o no.Esta tesis doctoral se centra en el desarrollo de nuevos métodos analíticos para determinar diferentes contaminantes orgánicos emergentes, como productos farmacéuticos de consumo generalizado, medios yodados de contraste para rayos-X (otro grupo de productos farmacéuticos empleados en medicina de diagnóstico) y un grupo de edulcorantes de alta intensidad en organismos acuáticos. Para ello se evaluaron dos técnicas de extracción (extracción con líquidos presurizados y QuEChERS) para extraer los compuestos seleccionados y también se ensayaron diferentes limpiezas. La determinación se realizó mediante cromatografía de líquidos acoplada a espectrometría de masas. Además, se realizó un estudio ecotoxicológico en la especie Gammarus pulex, donde se evaluó la toxicidad del triclosán para esta especie y, además, se estudiaron poblaciones procedentes de diferentes ambientes con diferentes grados de contaminación para determinar si su resistencia era similar o no.
This Doctoral Thesis focuses on the development of new analytical methods to determine different emerging organic contaminants such as pharmaceuticals of widespread consumption, iodinated X-ray contrast media (another group of pharmaceuticals employed in diagnostic medicine), and a group of high-intensity sweeteners, in aquatic organisms. To do so two extraction techniques (pressurised liquid extraction and QuEChERS) were evaluated to extract the selected compounds and different clean-ups were also tested. The determination was perfomed with liquid chromatography coupled with mass spectrometry. Moreover, another objective is to conduct an ecotoxicological study in the amphipod species Gammarus pulex, where the toxicity of triclosan to this species was evaluated. Moreover, populations that come from different environments with different degrees of pollution were evaluated in order to establish whether their resistance was similar or not.
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Bonnefille, Bénilde. "Evaluation de l’approche métabolomique pour l’étude de la métabolisation et des effets du diclofénac chez la moule méditerranéenne." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT085/document.
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Le travail de thèse présenté dans ce manuscrit porte sur la caractérisation de l’exposition des organismes aquatiques à un produit pharmaceutique (PP) et sur l’étude des perturbations métaboliques associées. Un PP récemment inclus dans la liste de vigilance de la directive cadre sur l’eau européenne (2015/495/EC), le DCF, et un organisme du milieu marin, Mytilus galloprovincialis, ont été choisis comme modèles de travail. L’approche méthodologique développée est une combinaison de l’analyse ciblée et non-ciblée des métabolites endogènes et exogènes (l’endo- et le xéno-métabolome) présents chez l’organisme d’étude suite à une exposition au DCF. L’évaluation des effets du DCF chez la moule par approche ciblée a été conduite sur la base de son mode d’action connu chez l’Homme : la modulation de la synthèse des prostaglandines (PG). Les PGs sont impliquées dans diverses fonctions, telles que la reproduction et l’osmorégulation chez les organismes aquatiques, et d’autres voies métaboliques sont susceptibles d’être impactées. Les résultats obtenus ont permis de mettre en évidence une sous-modulation de la synthèse de la PGE2 chez les moules exposées au DCF. Par ailleurs, peu d’informations sont disponibles concernant la métabolisation du DCF chez les invertébrés. Pour étudier la biotransformation et les effets du DCF chez la moule, l’application d’une approche non-ciblée nous semblait prometteuse. L’étude du xéno-métabolome m’a permis de mettre en évidence la formation de 13 métabolites, dont 3 de phase I et 10 de phase II. Parmi ces métabolites, 5 sont référencés pour la première fois dans la littérature. Par la suite, l’étude de l’endo-métabolome a permis de révéler la modulation de deux voies métaboliques : le métabolisme de la tyrosine et le métabolisme du tryptophane. Les catécholamines et la sérotonine ressortent comme particulièrement impactées dans ces deux voies métaboliques. Chez la moule, ces métabolites sont impliqués dans des fonctions biologiques importantes : l’osmorégulation et la reproduction et sont en accord avec les études menées chez d’autres organismes aquatiques. Le travail effectué a permis de mettre en évidence que l’application de l’approche métabolomique à des questions environnementales est pertinente et performante pour étudier la biotransformation et les effets non-documentés (différent du mécanisme d’action connu) d’un produit pharmaceutique chez des organismes non-cibles, sans hypothèse a prioriThis PhD thesis describes an investigation of the metabolomic approach performances to characterize the pharmaceuticals environmental exposure and effects in non target organisms. The studied pharmaceutical was diclofenac (DCF), a non-steroidal anti-inflammatory drug recently included in the first watch list of the European Water Framework Directive (2015/495/EC), and the model organism was the Mediterranean mussel Mytilus galloprovincialis. The methodological approach combines target and non-targeted analysis of endogenous and exogenous metabolites in mussel, the endo- and the xeno-metabolome. DCF effects in mussel were investigated considering its known mode of action in human: the prostaglandins (PG) synthesis modulation. In aquatic organisms, PGs are involved in various biological functions, such as reproduction or osmoregulation. This targeted analysis allowed us to determine a PGE2 synthesis disruption with DCF exposure. Otherwise, little information is available about DCF biotransformation in invertebrates. To study DCF biotransformation in mussel, the application of a non-targeted approach seemed promising. This study allows the reveal 13 DCF metabolites formation of which 3 were phase I metabolites and 10 were phase II metabolites. Among them, 5 were described for the first time. Subsequently, the mussel’s endo-metabolome study showed the modulation of two pathways: the tyrosine and the tryptophan metabolism. Inside these pathways, the catecholamines and serotonin appeared as particularly impacted. In mussels, these compounds are involved in important biological functions: the osmoregulation and the reproduction. Such DCF effects are in accordance with those reported in other study conducted on aquatic organisms. The work conducted highlighted the relevance and pertinence of the metabolomic approach as a tool for environmental studies without a priori hypothesis, such as studying the biotransformation and unexpected effects of pharmaceuticals in non-target organisms
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Chow, Stephanie S. Wold Barbara J. "Speciation in digital organisms /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-06062005-171257.
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Siebert, Tiago Henrique [UNESP]. "Análise do período de defeso do camarão marinho Artemesia longinaris através da maturidade ovariana anual." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/86662.
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siebert_th_me_jabo.pdf: 780967 bytes, checksum: 77d072c9560fa467e35c57e133f297b6 (MD5)O Artemesia longinaris é endêmica nas águas costeiras do Atlântico Sul, e ocorre a partir da costa do Rio de Janeiro até Puerto Rawson, Argentina. Assim, considerando a exploração das espécies naturais, é necessário estudar a dinâmica reprodutiva para a renovação do estoque natural da espécie, e contribuir para a adequação do fechamento da pesca. O objetivo deste estudo foi caracterizar morfologicamente os diferentes estágios de desenvolvimento dos ovócitos, a maturação dos ovários durante todo o ano, e a avaliação do fechamento de pesca atual para a espécie na região de Macaé / RJ. Para a análise de microscopia de luz (histologia e histoquímica), seis animais de cada estágio de maturação gonadal (rudimentar - RU, em desenvolvimento - ED e desenvolvidos -D) foram coletados na região de Macaé, RJ. Os ovários foram dissecados e fixados em solução de Bouin, incluídos em historesina, corados com hematoxilina / eosina e reação ao ácido periódico de Schiff (PAS). Para a avaliação do período de pesca, usamos fêmeas com gônadas desenvolvidas (D) na primavera, verão, inverno e outono. O número de ovócitos maduros encontrados em cada espécime estudado foi contado ao longo do ano usando o software ImageJ®. Em seguida, o número médio de ovócitos maduros encontrados foi avaliado em cada estação do ano, com o programa SigmaPlot® versão 12. O ovário de A. longinaris apresenta quatro estágios de maturação: rudimentar, desenvolvimento inicial, desenvolvimento avançado e desenvolvido. As células germinativas apresentam cinco fases de desenvolvimento: ovogônias, ovócitos pré-vitelogênicos, ovócitos em vitelogênese inicial, ovócitos em vitelogênese avançado e ovócitos maduros. Novembro apresentou a maior média de ovócitos maduros nos ovários desenvolvidos. Assim a avaliação do...
Artemesia longinaris is endemic in the coastal waters of the South Atlantic, and occurs from the coast of Rio de Janeiro to Puerto Rawson, Argentina. Thus, considering the exploitation of natural species, it is necessary to study the reproductive dynamics for the renewal of the natural stock of the specie, and contribute to the adequacy of the fishing closure. The aim of this study was to characterize morphologically the different developmental stages of oocytes, ovarian maturation throughout the year, and the evaluation of current fishing closure for the species in the region of Macaé/RJ. For analysis of light microscopy (histology and histochemistry), 6 animals of each stage of gonadal maturation (rudimentary - RU, in development - ED and developed -D) were collected in the region of Macaé, RJ. The ovaries were dissected and fixed in Bouin's solution, embedded in historesin, stained with hematoxylin/eosin and reacted to Periodic acid Schiff (PAS). For the evaluation of the fishery period, we used females with developed gonads (D) in spring, winter, summer and autumn. The number of mature oocytes found in each specimen studied was counted over the year using the ImageJ software®. Then, the average number of mature oocytes found was evaluated in each season, with the program SigmaPlot® version 12. The ovary of A. longinaris presents four stages of maturation: rudimentary, initial development, advanced development and developed. The germinal cells present five development phases: oogonia, pre-vitellogenic oocytes, initial-vitellogenic oocyte, advanced vitellogenic oocyte, and mature oocyte. November had the highest average of mature oocytes in the ovaries developed. The annual reproductive cycle assessment indicated that the most appropriate period for fishing closures for this species is from November to January... (Complete abstract click electronic access below)
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Siebert, Tiago Henrique. "Análise do período de defeso do camarão marinho Artemesia longinaris através da maturidade ovariana anual /." Jaboticabal, 2013. http://hdl.handle.net/11449/86662.
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Orientador: Irene Bastos Franceschini VicentiniCoorientador: Rogério Caetano da Costa
Banca: Maíra Aparecida Stefanini
Banca: Bruno Cesar Schimming
Resumo: O Artemesia longinaris é endêmica nas águas costeiras do Atlântico Sul, e ocorre a partir da costa do Rio de Janeiro até Puerto Rawson, Argentina. Assim, considerando a exploração das espécies naturais, é necessário estudar a dinâmica reprodutiva para a renovação do estoque natural da espécie, e contribuir para a adequação do fechamento da pesca. O objetivo deste estudo foi caracterizar morfologicamente os diferentes estágios de desenvolvimento dos ovócitos, a maturação dos ovários durante todo o ano, e a avaliação do fechamento de pesca atual para a espécie na região de Macaé / RJ. Para a análise de microscopia de luz (histologia e histoquímica), seis animais de cada estágio de maturação gonadal (rudimentar - RU, em desenvolvimento - ED e desenvolvidos -D) foram coletados na região de Macaé, RJ. Os ovários foram dissecados e fixados em solução de Bouin, incluídos em historesina, corados com hematoxilina / eosina e reação ao ácido periódico de Schiff (PAS). Para a avaliação do período de pesca, usamos fêmeas com gônadas desenvolvidas (D) na primavera, verão, inverno e outono. O número de ovócitos maduros encontrados em cada espécime estudado foi contado ao longo do ano usando o software ImageJ®. Em seguida, o número médio de ovócitos maduros encontrados foi avaliado em cada estação do ano, com o programa SigmaPlot® versão 12. O ovário de A. longinaris apresenta quatro estágios de maturação: rudimentar, desenvolvimento inicial, desenvolvimento avançado e desenvolvido. As células germinativas apresentam cinco fases de desenvolvimento: ovogônias, ovócitos pré-vitelogênicos, ovócitos em vitelogênese inicial, ovócitos em vitelogênese avançado e ovócitos maduros. Novembro apresentou a maior média de ovócitos maduros nos ovários desenvolvidos. Assim a avaliação do... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Artemesia longinaris is endemic in the coastal waters of the South Atlantic, and occurs from the coast of Rio de Janeiro to Puerto Rawson, Argentina. Thus, considering the exploitation of natural species, it is necessary to study the reproductive dynamics for the renewal of the natural stock of the specie, and contribute to the adequacy of the fishing closure. The aim of this study was to characterize morphologically the different developmental stages of oocytes, ovarian maturation throughout the year, and the evaluation of current fishing closure for the species in the region of Macaé/RJ. For analysis of light microscopy (histology and histochemistry), 6 animals of each stage of gonadal maturation (rudimentary - RU, in development - ED and developed -D) were collected in the region of Macaé, RJ. The ovaries were dissected and fixed in Bouin's solution, embedded in historesin, stained with hematoxylin/eosin and reacted to Periodic acid Schiff (PAS). For the evaluation of the fishery period, we used females with developed gonads (D) in spring, winter, summer and autumn. The number of mature oocytes found in each specimen studied was counted over the year using the ImageJ software®. Then, the average number of mature oocytes found was evaluated in each season, with the program SigmaPlot® version 12. The ovary of A. longinaris presents four stages of maturation: rudimentary, initial development, advanced development and developed. The germinal cells present five development phases: oogonia, pre-vitellogenic oocytes, initial-vitellogenic oocyte, advanced vitellogenic oocyte, and mature oocyte. November had the highest average of mature oocytes in the ovaries developed. The annual reproductive cycle assessment indicated that the most appropriate period for fishing closures for this species is from November to January... (Complete abstract click electronic access below)
Mestre
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Bajrai, Leena. "Organisms associated with amoebae infection." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0055.
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Cette thèse présente nouveaux organismes trouvés dans d'échantillons d'eaux usées proviennent la zone sud de Jeddah, en Arabie Saoudite. Legionella saoudiensis, Kaumoebavirus, moumouvirus saoudien (SDMV), Yasminevirus et Bunga messiliensis qui sont isolés par une méthode de co-culture amibienne d'infection par Dictyostelium discoideum ATCC 44841, Vermamoeba vermiformis CDC-19, Acanthamoeba polyphaga Linc AP-1 , et Acanthamoeba griffinii, respectivement. Legionella saoudiensis, une souche bactérienne Gram-négative, en forme de bacille, LS-1T appartient au genre Legionella de la famille des Legionellaceae, basée sur des séquences de gène 16S rRNA et d'autres 4 gènes (mip, rpoB, rnpB et 23S-5S). D'une part, le KAUmoebavirus a des capsides icosaédriques de ~ 250 nm-large, un génome d'ADN de 350 731 pb, et une densité de codage de 86%, correspondant à 465 gènes. La plupart de ces gènes (59%) sont étroitement liés aux gènes de Faustoviruses (43%) et Asfarviruses (23%). D'autre part, le moumouvirus saoudien est un nouveau virus géant appartenant à la lignée Mimivirus B, de l'hôpital universitaire King Abdulaziz à Djeddah, et a présenté des particules icosaédriques de 500 nm avec un génome de 1 046 087 pb, plus grand que les génomes moumouvirus qui ont été décrites dans le passé. Il a été prédit que son génome code pour 868 ORF, dont la taille varie de 54 à 2 914 acides aminés. En outre, il code pour 40 nouveaux gènes (ORFans) sans similitude avec d'autres séquences. Ces résultats montrent que la dispositiond’une carte élargie des protistes conduit à découvrir de nouveaux virus géantsThis thesis displays novel organisms that are found in sewage water samples from southern area of Jeddah, Saudi Arabia. These organisms are Legionella saoudiensis, Kaumoebavirus, Saudi moumouvirus (SDMV), Yasminevirus, and Bung messiliensis that are isolated by amoebal co-culture method of infection with Dictyostelium discoideum ATCC 44841, Vermamoeba vermiformis CDC-19, Acanthamoeba polyphaga Linc AP-1, and Acanthamoeba griffinii, respectively. Legionella saoudiensis, a Gram-negative, bacilli shaped bacterial strain, LS-1T belongs to the genus Legionella in the family Legionellaceae based on 16S rRNA gene sequences and other 4 genes (mip, rpoB, rnpB, and 23S-5S). On one hand, KAUmoebavirus has ~250-nm-large icosahedral capsids, a 350,731 bp DNA genome, and a coding density of 86%, corresponding to 465 genes. Most of these genes (59%) are closely related to genes from Faustoviruses (43%) and Asfarviruses (23%). On the other hand, Saudi moumouvirus is a new giant virus belonging to Mimivirus lineage B, from the King Abdulaziz University hospital in Jeddah, and presented 500 nm icosahedral particles with a 1,046,087 bp genome, which is larger than moumouvirus-like genomes which have been described in the past. Its genome was predicted to encode 868 ORFs, ranging in size from 54 to 2,914 amino acids. Furthermore, this genome was predicted to encode 40 new genes (ORFans) without similarity with other sequences. These findings show that the widen chart of protists apply lead to discover new giant viruses
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Vonsée, Henk John. "Urogenital micro-organisms in pregnancy." Maastricht : Maastricht : Datawyse ; University Library, Maastricht University [Host], 1989. http://arno.unimaas.nl/show.cgi?fid=5510.
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Mudge, Stephen Michael. "Carbonic anhydrase in marine organisms." Thesis, Bangor University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318943.
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Zhou, Yuming. "Optical properties of living organisms." Thesis, Open University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301878.
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Beanland, Timothy James. "The phylogeny of photosynthetic organisms." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385339.
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Miller, Luke Rex. "Evolution of highly fecund organisms." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:60a9fcc7-b939-4075-be31-ed69014ad898.
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We develop and study the high-density limit of various new models in mathematical pop- ulation genetics. These models extend the Λ-Fleming–Viot process when there are two genetic types at the locus of study. Given a finite sample from a population undergoing these dynamics, a key tool for understanding the corresponding genealogy is the method of duality. We introduce the reproduction-linked mutation mechanism and consider how this affects the process of relative allelic frequencies and the genealogy. The second generalization incorporates two forms of natural selection – differential killing and differential birth. We contrast the structure of their genealogies. Several properties of the block size spectra of the Kingman and Beta coalescents are also investigated, including their behaviour as they come down from infinity.
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Reggi, Michela <1986>. "Biomineralization in calcifying marine organisms." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7096/1/Michela_Reggi_Tesi.pdf.
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The objective of this theses is to contribute to the wide discussion about the biological control level on the biomineralization operated by calcifying organisms. In particular the intra-crystalline organic matrix associated with different coral species was studied and its role in the process was investigated. The main goals obtained from the research on corals included: (i) the discovery of the species specific role of the intra-crystalline organic matrix molecules in the precipitation of calcium carbonate; (ii) the definition of the role of magnesium ions in the control of the macromolecules assembly/aggregation and in the consequent calcium carbonate polymorphic selectivity; (iii) the discovery that in corals the biomineralization process is not affected by the sea water acidity, as consequence corals are able to construct their skeletons independently from the environmental conditions as far they survive.
At the same time, investigations on different kind of vaterite, biogenic and synthetic, were also carried out and confirm the importance of the organism control on the biomineralization process and in particular on the co-existence of different crystalline structures of vaterite for enabling optimization of specific functions, through the employment of OM and acidic macromolecules.
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Reggi, Michela <1986>. "Biomineralization in calcifying marine organisms." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7096/.
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The objective of this theses is to contribute to the wide discussion about the biological control level on the biomineralization operated by calcifying organisms. In particular the intra-crystalline organic matrix associated with different coral species was studied and its role in the process was investigated. The main goals obtained from the research on corals included: (i) the discovery of the species specific role of the intra-crystalline organic matrix molecules in the precipitation of calcium carbonate; (ii) the definition of the role of magnesium ions in the control of the macromolecules assembly/aggregation and in the consequent calcium carbonate polymorphic selectivity; (iii) the discovery that in corals the biomineralization process is not affected by the sea water acidity, as consequence corals are able to construct their skeletons independently from the environmental conditions as far they survive.
At the same time, investigations on different kind of vaterite, biogenic and synthetic, were also carried out and confirm the importance of the organism control on the biomineralization process and in particular on the co-existence of different crystalline structures of vaterite for enabling optimization of specific functions, through the employment of OM and acidic macromolecules.
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Pathirana, Induruwa Charles. "Secondary metabolites from selected marine organisms." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27506.
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Marine organisms are known to produce secondary metabolites which have novel structures and are often biologically active. Chemical studies of biologically active metabolites from three different marine organisms led to the discovery of six new compounds and six previously known compounds.
The brown alga Dictyota binghamiae is fairly abundant in British Columbia coastal waters. A chemical study of this alga yielded ten diterpenoids of which four are new compounds. All the new compounds, dictyoxide A (66), dictyol G acetate (68), dictyotriol A diacetate (69), and epidictyol B acetate (70) contain a perhydroazulene carbon skeleton first encountered in the algal metabolite pachydictyol A (29). Dictyoxide A (66) appears to be an artifact of isolation. The acetates 68, 69, 70 were found to be antibacterial and antifungal. Six previously known compounds pachydictyol A (29), dictyol C (32), dictyoxide (35), acetyldictyolal (49) and the acetals 61a and 61b were also isolated from this alga.
Chemical studies on an Agelas sp. of sponge collected in Sri Lanka yielded the antimicrobial metabolite desbromooroidin (79).
An interesting interaction between the starfish Dermasterias imbricata and the sea anemone Stompia coccinea was observed a long time ago. When contacted by the starfish, the anemone displays an unusual "swimming" response which was, according to other subsequent studies, caused by a single chemical substance in the starfish. A study conducted to elucidate the structure of this starfish metabolite led to the isolation of imbricatine (91), a unique benzyltetrahydroisoquinoline alkaloid. Imbricatine (91) induced S. coccinea swimming response at a very low concentration and also exhibited antitumor activity.
Structures of all the new metabolites were determined by spectral analysis, and chemical degradations and chemical interconversions.Science, Faculty of
Chemistry, Department of
Graduate
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Till, Marisa. "Studies of New Zealand Marine Organisms." The University of Waikato, 2007. http://hdl.handle.net/10289/2498.
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The chemical study of three New Zealand marine organisms is described, along with a survey of the chemistry and biological activity of eighty-five marine organisms collected from New Zealand waters. The study of the New Zealand marine bryozoan Pterocella vesiculosa has resulted in the isolation of three new compounds; pterocellin H, pterocellin I and 1-methyl-5-bromo-8-methoxy-β-carboline. These compounds were characterised using high resolution mass spectrometry, one- and two-dimensional nuclear magnetic resonance spectroscopy and X-ray crystallography. The biological activity of these compounds was investigated and a discussion of the results including a comparison with the activity of closely related compounds is also presented. The crude extracts of eighty-five marine organisms were surveyed to establish their biological activity and chemical constituents. The results of this study indicated which species had interesting biological activity. The chemical survey allowed geographical and intra-species comparisons of chemical constituents between samples, as well as potentially indicating the presence of known secondary metabolites. For the Pterocella vesiculosa samples the survey methodology clearly illustrated the presence of pterocellins A and B. Two marine organisms were chosen for further investigation based on their biological activity and chemical survey results. Bioactivity directed isolation procedures yielded no new compounds from the organisms. The sterol composition of these species is also presented.
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Edwards, N. J. "Ammonia metabolism in rumen mirco-organisms /." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09AB/09abe26.pdf.
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Psarrakos, Panagiotis. "Disulphide bond formation in multicellular organisms." Thesis, University of Kent, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497681.
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Carter, Laura. "Uptake of pharmaceuticals into terrestrial organisms." Thesis, University of York, 2013. http://etheses.whiterose.ac.uk/4678/.
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Over the past decade, there has been increasing scientific interest in the occurrence, fate and effects of pharmaceuticals in the environment. To date, the majority of this research has focussed on the aquatic environment whilst the terrestrial environment has remained relatively unexplored. Research carried out in the terrestrial environment has primarily focussed on the fate of pharmaceuticals in soils as well as the uptake of pharmaceuticals into plants. Less information is available on the uptake of pharmaceuticals into other soil dwelling species. The studies presented in the thesis were therefore performed to investigate the uptake of pharmaceuticals into earthworm species (Eisenia fetida and Lumbricus terrestris) and plant species (radish and ryegrass). Experiments were designed to explore the effect of pharmaceutical physico-chemical properties, soil parameters and species traits on the uptake of pharmaceuticals from soils into terrestrial species. Understanding the factors and processes involved in the uptake of these compounds from soils, is vital to adequately assess the risks of pharmaceuticals in the environment. Initial experimental studies evaluated the uptake of four pharmaceuticals, namely carbamazepine, diclofenac, fluoxetine and orlistat into the earthworm, Eisenia fetida. Pore water based bioconcentration factors (BCFs) increased in the order of carbamazepine < diclofenac < fluoxetine and orlistat. As well as experimental research, a desk based investigation was perfomed to assess the applicability of a minimised design approach to estimate bioconcentration factors (BCFs) in terrestrial and aquatic species. A significant regression between BCFminimised and BCFtraditional was found and this approach was therefore adopted to calculate earthworm BCFs in the soil parameters and species traits studies described below. The uptake of the four study pharmaceuticals by E. fetida was therefore further evaluated in different soil types. The uptake and accumulation of pharmaceuticals into E. fetida changed depending on soil type. Orlistat exhibited the highest pore water based bioconcentration factors (BCFs) and displayed the largest differences in uptake between soil types as BCFs ranged between 30.51 – 115.92. For carbamazepine, diclofenac and fluoxetine BCFs ranged between 1.05 – 1.61, 7.02 – 69.57 and 16.78 – 20.42 respectively. Supplementary studies compared the uptake of the study pharmaceuticals in two earthworms (Lumbricus terrestris and E. fetida). All four pharmaceuticals were taken up by both L. terrestris and E. fetida tissue after 21 d exposure to spiked soil. Pore water based bioconcentration factors (BCFs) ranged between 6.69 and 83.79 for L. terrestris and 1.14 and 63.03 for E. fetida. The effect of species type on the uptake of pharmaceuticals (carbamazepine, diclofenac, fluoxetine, propranolol, sulfamethazine) and a personal care product (triclosan) was also investigated in plant species (radish, Raphanus sativus and ryegrass, Lolium perenne). Five of the six chemicals were taken up into plant tissue, carbamazepine to the greatest extent in both the radish (52 µg/g) and ryegrass (33 µg/g) whereas sulfamethazine uptake was below the limit of quantitation (LOQ). The results demonstrate the ability of plant species and earthworms to accumulate pharmaceuticals from soils with uptake apparently specific to both species, chemical and soil type. However the influence of these individual parameters does not affect BCFs to a significant amount. The research also highlights that a combination of factors and processes appear to be driving the uptake into soil dwelling species as further analysis was unable to find a single parameter to adequately explain pharmaceutical uptake into terrestrial species. For example, for plant uptake, results could only be partly explained by the hydrophobicity and extent of ionisation of each chemical in the soil. Even though these chemicals are taken up by earthworms and plants, further analysis showed that the risk to predatory birds is minimal based on the current environmental scenarios as thousands of worms would have to be consumed by a bird to receive a single dose. Similarly, the potential risk to humans consuming crops contaminated with pharmaceutical residues is also minimal. However with increasing loadings of pharmaceuticals to soils this may result in potential problems for human health and predatory birds in the future.
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Bi, Ran. "Lignocellulose Degradation by Soil Micro-organisms." Doctoral thesis, KTH, Träkemi och massateknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-182336.
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Lignocellulosic biomass is a sustainable resource with abundant reserves. Compared to petroleum ‐ based products, the biomass ‐ derived polymers and chemicals give better environmental profiles. A lot of research interest is focused on understanding the lignocellulose structures. Lignin, among the three major wood components, represents most difficulty for microbial degradation because of its complex structure and because cross ‐ linking to hemicellulose makes wood such a compact structure. Nevertheless, wood is naturally degraded by wood ‐ degrading micro ‐ organisms and modified and partly degraded residual of lignin goes into soil. Therefore soil serves as a good environment in which to search for special lignin ‐ degraders. In this thesis, different types of lignin have been used as sole carbon sources to screen for lignin ‐ degrading soil micro ‐ organisms. Eleven aerobic and three anaerobic microbe strains have been isolated and identified as able to grow on lignin. The lignin degradation patterns of selected strains have been studied and these partly include an endwise cleavage of β‐ O ‐ 4 bonds in lignin and is more complex than simple hydrolytic degradation. As lignin exists in wood covalently bonded to hemicellulose, one isolated microbe strain, Phoma herbarum, has also been studied with regards to its ability to degrade covalent lignin polysaccharide networks (LCC). The results show that its culture filtrate can attack lignin ‐ polysaccharide networks in a manner different from that of the commercial enzyme product, Gammanase, possibly by selective cleavage of phenyl glucoside bonds. The effects on LCC of Phoma herbarum also enhance polymer extractability. Hot ‐ water extraction of a culture filtrate of Phoma herbarum ‐ treated fiberized spruce wood material gave an amount of extracted galactoglucomannan more than that given by the Gammanase ‐ treated material and non ‐ enzyme ‐ treated material. Over millions of years of natural evolution, micro ‐ organisms on the one hand develop so that they can degrade all wood components to get energy for growth, while plants on the other hand also continuously develop to defend from microbial attack. Compared with lignin and cellulose, hemicelluloses as major components of plant cell walls, are much more easily degraded, but hemicelluloses differ from cellulose in that they are acetylated to different extents. The biological functions of acetylation are not completely understood, but it is suggested is that one function is to decrease the microbial degradability of cell walls. By cultivation of soil micro ‐ organisms using mannans acetylated to deffernent degrees as sole carbon source on agar plates, we were able to see significant trends where the resistance towards microbial degradation of glucomannan and galactomannan increased with increasing degree of acetylation. Possible mechanisms and the technological significance of this are discussed. Tailoring the degree of acetylation of polysaccharide materials might slow down the biodegradation, making it possible to design a material with a degradation rate suited to its application.QC 20160223
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Allen, Catherine Elizabeth. "Lipid profiles of deep-sea organisms." Thesis, University of Southampton, 1998. https://eprints.soton.ac.uk/42077/.
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Lipids are a group of biologically important compounds that may be used as indicators of relationships between an organism and its environment. Lipid class composition identifies types of storage lipid which can suggest a pelagic or benthic existence and may be used to measure the condition of an organism. Fatty acid composition may reflect trophic ecology. Lipid profiling has been used to elucidate elements of the ecology of organisms from Mid-Atlantic and Juan de Fuca Ridge hydrothermal vents and shrimp from below a permanent oxygen minimum zone. Lipid profiles of these organisms from extreme deep-sea environments are compared. Lipid profiles of adult Mid-Atlantic Ridge hydrothermal vent shrimp, Rimicaris exoculata. support a benthic existence and primarily chemoautotrophic bacterial nutrition. Postlarval alvinocarid shrimp lipid profiles suggest a pelagic life cycle stage with a reliance on phototrophically derived organic matter. This result supports previous molecular evidence that Rimicaris exoculata travels between hydrothermal vents on the Mid-Atlantic Ridge. The branchial area of Rimicaris exoculata has been reported to be colonised with bacteria and elevated levels of bacterial fatty acids are present in these tissues. Lipid analyses of the reproductive organs of Rimicaris exoculata reveal increases in triglycerides, sterols, phosphatidyl choline and the proportion of n-3 fatty acids with advancing reproductive maturity. Preliminary studies of the lipid profiles of the Mid-Atlantic vent shrimp Alvinocaris markensis support the hypothesis that it is a scavenger and contains a lower proportion of bacterially derived fatty acids. The lipid profiles of the deep-sea shrimp, Nematocarcinus gracilis, from the Indian Ocean, were consistent with a benthic lifestyle, opportunistic feeding and a reliance on phototrophically derived organic matter. Despite the presence of a permanent oxygen minimum zone above the habitat of the shrimp, Nematocarcinus gracilis contain low levels of highly unsaturated fatty acids, reflecting a reduction in the availability of labile organic matter with depth. The hydrothermal vent tube worm Ridgeia piscesae contains only low levels of storage lipid, reflecting an extreme reliance on endosymbiotic bacteria. Wax esters detected are thought to be stored in oocytes. The fatty acid profile of Ridgeia piscesae reveal mainly bacterial biomarker fatty acids, but some phototrophically derived fatty acids are also present. Adult Ridgeia piscesae have no gut, so the mechanism by which these fatty acids are assimilated is uncertain. Lipid profiles of the hydrothermal vent palm worm, Paralvinella palmiformis vary with the conditions of the different microenvironments in which specimens were found. Fatty acids reflect a mixed diet based mainly on chemoautotrophic bacteria, but with significant inputs of phototrophically derived organic matter, such as diatom debris. Phototrophically derived fatty acids were also detected in the hydrothermal vent clam Calyptogena pacifica. suggesting that the reduced filter-feeding ability of this species is used to supplement nutrition from endosymbiotic bacteria. Endosymbiont-bearing gill tissues contain the highest proportion of bacterial fatty acids and also high concentrations of triglycerides. The presence of triglycerides in gill tissues suggests that energy may be transferred from symbionts by hydrolysis of bacterial symbiont membrane lipids and their conversion to triglyceride. The lipid profiles presented in this work increase understanding of the life history strategies and ecology of the species studied. This thesis shows that even the most highly adapted hydrothermal vent organisms do not rely solely on a chemoautotrophic source of nutrition, but also appear to require phototrophically derived elements in their diet.
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Pao, Shi-Chiang. "Halophilic organisms in sufu, Chinese cheese /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487857546388848.
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López, i. Losada Raül. "Analysing toxicity for biochemical-producing organisms." Thesis, KTH, Hållbarhet och miljöteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235713.
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Using macroalgae as bio-feedstock for the bio-based plastic industry is a developing process that possesses inherent comparative advantages with regard to its environmental impacts compared to using other bio-feedstock sources. Thus, research effort is considered necessary to improve its competitiveness and resolve the technical challenges that it is currently facing. Within this context, this thesis aims at improving existing knowledge on ecotoxicity impacts from metals found in macroalgae tissue to microbes used within bio-reactors for their fermentation. The basis for a novel impact pathway within LCA methodologies is provided according to a fate- exposure-effect approach. Namely: microbial biota within a bio-reactor is exposed to metal that is bioaccumulated by macroalgae tissue from background sea water, which derives into potential ecotoxicity effects. This pathway can be further studied to incorporate microbial ecotoxicity in bio- reactors within current LCA practices. Under this approach, two data sets have been analysed to evaluate levels of pollution of metals in macroalgae feedstocks against their potential ecotoxicological effects in biochemicals producing microbes: one concerning metal uptake by macroalgae, including measurements on algae tissue and background sea water; and a second one including metal ecotoxicity measurements on relevant microbial species used in biochemicals production processes. As a result of this analysis, it is concluded that there is basis for including microbial ecotoxicity from macroalgae feedstock as a relevant criterion within decision-making in the bio-based plastic industry. Moreover, input for the industry is obtained as direct recommendations and score tables that can be used under case-specific scenarios for macroalgae and microbial species selection. The conducted project should be regarded as a first iteration to the problem. Further work is required in order to refine the outcome of research and maximise input recommendations for the bio-based plastic industry.
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Maeda, Hiroshi. "Vitamin E functions in photosynthetic organisms." Diss., Connect to online resource - MSU authorized users, 2006.
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Smith, E. C., Phillip R. Scheuerman, and Kurt J. Maier. "Toxicity of Nanomaterials to Aquatic Organisms." Digital Commons @ East Tennessee State University, 2005. https://dc.etsu.edu/etsu-works/2939.
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Hoffman, Jennifer. "Effects of and defenses against ultraviolet radiation in marine embryos and larvae /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/5243.
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Lamotte, Hadrien. "Libération de composés intracellulaires par application d'arcs électriques entre électrodes immergées." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI122/document.
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Cette thèse est consacrée à l’étude d’une technique innovante de lyse de microorganismes, fondée sur l’utilisation d’impulsions haute tension en milieu aqueux. Cette technique se distingue de l’électroporation qui exploite le champ électrique produit pour dégrader la membrane cellulaire ; dans notre étude les impulsions haute tension permettent la formation d’arcs électriques produisant de multiples phénomènes physico-chimiques qui peuvent entraîner la lyse des microorganismes.L’efficacité du procédé a été évalué sur les microorganismes suivants : des microalgues productrices d’huile (Nannochloropsis gaditana et Phaeodactylum tricornutum) et des bactéries couramment utilisées comme modèles de laboratoire (Escherishia coli et Bacillus subtilis). Dans ces travaux, nous avons montré que les ondes de pression produites sont principalement responsables de la lyse.En fin d’étude, des perspectives sont explorées en vue du développement de systèmes autonomes soit dans le cadre de la bioproduction, soit dans le cadre de l’analyse cellulaireThis thesis focuses on the study of an innovative technology for microorganisms lysis, based on high voltage pulses generated in an aqueous medium. This technology is different from electroporation which operates thanks to the electric field for damaging cell membranes ; in our study high voltage pulses generate an electric arc leading to various physicochemical phenomena supposed to lyse microorganisms.The technology efficiency is evaluated with the following microorganims : some lipid producting microalgae (Nannochloropsis gaditana and Phaeodactylum tricornutum) and classical laboratory model bacteria (Escherishia coli and Bacillus subtilis). In this work, we found that generated shock waves are mainly responsible of the cells lysis.At the end, the development of self-functioning devices is investigated either for bioproduction or for cell analysis
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Oehmen, Adrian. "The competition between polyphosphate accumulating organisms and glycogen accumulating organisms in the enhanced biological phosphorous removal process /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18339.pdf.
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Heuett, William J. "New methods for modeling large-scale biochemical networks /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6769.
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Panzarini, Nathalie Hamine. "Panorama de OGM’S na cadeia de suprimentos de farinhas e preparados a base de trigo." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1564.
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CAPESOs debates atuais sobre a inserção dos OGM’s nos produtos alimentícios, bem como seus riscos e benefícios no que diz respeito a alimentos, continuam inconclusos. Percebe-se que a sociedade em geral tem informação insuficiente a respeito do assunto e as empresas que estão envolvidas não realizam uma exposição eficiente a respeito do assunto. No Brasil, existem poucos laboratórios públicos ou privados que trabalham com a finalidade objetivo de detectar e quantificar os resíduos OGM’s em alimentos. Torna-se fundamental que as informações sobre esse tipo de produto, cada vez mais consumido em forma de alimento, estejam claras e bem entendidas por todos os atores da cadeia de suprimentos relacionadas com essa inovação agroalimentar, como seus riscos e benefícios, a liberação e comercialização e rotulagem. Assim, o estudo teve por objetivo identificar o grau de conhecimento e os impactos da inserção da inovação OGM’s na cadeia de suprimentos de farinhas e preparados a base de trigo. Como instrumento para a obtenção dos dados utilizou-se método de pesquisa empregado foi o survey por meio da aplicação direta de questionários semiestruturados, aplicados com produtores da região dos Campos Gerais, moinhos e indústrias de farinhas de trigo e consumidores. Ademais, mapeou-se os laboratórios e tecnologias para o diagnóstico de OGM’s em alimentos. A partir da realização da pesquisa, tem-se como resultado, que comparando com estudos internacionais o grau de conhecimento referente à inserção dessa tecnologia nos produtos alimentícios, seus riscos e benefícios e principalmente sua rotulagem ainda são baixos, pois frequentemente os rótulos dos produtos alimentícios geram dúvidas, descrédito e insatisfação em relação às informações, bem como a insatisfação da informação quanto aos efeitos do uso dessa biotecnologia para a saúde humana e do meio ambiente. O Brasil apresenta poucos laboratórios de controle de OGM’s em alimentos, observando uma crescente utilização da técnica de PCR para a detecção e quantificação de OGM’s. Contudo, a padronização dos métodos dessa análise ainda está no início. Neste sentido a inserção de produtos que obtenham OGM’s em sua composição no mercado, requer esforço e maior envolvimento entre os atores da cadeia de suprimentos, a medida que o desenvolvimento desse tecnologia impõe padrões como rastreabilidade e certificação , que afetam diretamente o processo produção e devem estar disponíveis da forma mais clara e objetiva para os consumidores.
Current debates on the inclusion of GMOs in food products, as well as their risks and benefits with regard to food, remain inconclusive. It is noticed that society in general has insufficient information on the subject and the companies that are involved do not realize an efficient exposure to the subject. In Brazil there are few public or private laboratories working in order order to detect and quantify GMO residues in food. It is essential that the information on this type of product, increasingly consumed as food, are clear and well understood by all actors in the chain of supplies related to this agri-food innovation, as their risks and benefits, and the release marketing and labeling. Thus, the study aimed to identify the degree of knowledge and the impact of the inclusion of GMOs innovation in supply chain meal and prepared wheat based. As a tool for data collection was used research method used was survey by direct application of semi-structured questionnaires administered to producers in the region of Campos Gerais, mills and wheat flour industries and consumers. Moreover, it was mapped laboratories and technologies for the diagnosis of GMOs in food. From the day of research, we have as a result, that compared to international studies the level of knowledge regarding the integration of this technology in food products, their risks and benefits and especially their labeling are still low because often the labels of food products generate doubts, disbelief and dissatisfaction with information as well as the dissatisfaction of information on the effects of using this biotechnology for human health and the environment. Brazil has few GMO control laboratories in food, noting the growing use of the PCR technique for the detection and quantification of GMOs. However, the standardization of methods of this analysis is still early. In this regard the inclusion of products obtain GMOs in their composition in the market, requires effort and greater involvement by actors in the supply chain, as the development of this technology imposes standards such as traceability and certification, which directly affect the process production and should be available as clearly and objectively to consumers.
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Kachtík, Michal. "Revitalizace vybraného úseku vodního toku." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240187.
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The topic of the submitted thesis is to carry out revitalization of a selected section of a watercourse. At first, the actual conditions of the riverbed and its surroundings are described. In the following part of the thesis the description of the newly designed watercourse section is focused. The main goal of the new design is to improve the life conditions both in and around the watercourse as well as to support its self-cleaning process.
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Avio, Carlo Giacomo. "Ecotoxicological risk of microplastics for marine organisms." Doctoral thesis, Università Politecnica delle Marche, 2016. http://hdl.handle.net/11566/243067.
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La presenza di Microplastiche (MP) negli oceani rappresenta una problematica emergente per l’ecosistema marino; è ormai stato dimostrato che le MP possono essere ingerire da diverse specie di organismi, ma non è stata ancora dimostrata la capacità di trasferimento trofico e di accumulo di queste microparticelle, e sono ancora molto carenti le informazioni sui effetti avversi indotti.
In questo lavoro di ricerca, il ruolo di alcuni polimeri plastici, come vettori di inquinanti chimici, è stato inizialmente valutato su campioni di macro-plastiche vergini, macro- e micro-plastiche spiaggiate. Tramite esperimenti di laboratorio, sono state invece studiate sia le cinetiche di adsorbimento del pirene e del cadmio in MP di polietilene (PE) e polistirene (PS), che la loro capacità di trasferire i composti adsorbiti ai mitili, Mytilus galloprovincialis. In questi organismi esposti sono stati analizzati diversi effetti a livello molecolare, biochimico e cellulare, incluse le risposte immunologiche, le alterazioni lisosomiali, la proliferazione perossisomiale, le difese antiossidanti, gli effetti neurotossici, genotossici oltre che il profilo di espressione genica.
E’ stato inoltre ottimizzato e applicato un nuovo protocollo per l'estrazione e caratterizzazione (FT-IR) delle MP su diverse specie di pesci e invertebrati del Mar Mediterraneo.
I livelli di IPA maggiori sono stati misurati nelle micro e macro-plastiche spiaggiate, mentre un efficiente assorbimento delle sostanze chimiche è stato confermato, sia per il PE che PS, con una modalità di adsorbimento tempo e dose-dipendente. Indagini istologiche hanno rivelato la presenza di MP nell’emolinfa, nelle branchie e nei tessuti digestivi dei mitili. Gli IPA adsorbiti sono stati rilasciati dalle MP e accumulati nei tessuti dei mitili che hanno mostrato alterazioni di diversi biomarker sia molecolari che cellulari. Il protocollo di estrazione sviluppato ha permesso di dimostrare la presenza di MP nello stomaco e, per la prima volta, nel fegato di cefali esposti. Studi sul campo hanno evidenziato la presenza di particelle nel 38% degli organismi selvatici analizzati, con una maggior frequenza di MP sotto forma di frammenti e linee, costituiti preferenzialmente da PE, PS e nylon.
In conclusione, questa tesi fornisce nuove informazioni sui rischi ecotossicologici delle MP per gli organismi marini oltre che un’importante linea di base sul livello di contaminazione da MP nel biota Mediterraneo.Microplastics (MPs) are a growing but still unexplored environmental concern for marine organisms. Although several species can ingest MPs, a clear evidence of their accumulation pathways, trophic transfer and adverse effects is still lacking. In this thesis, the potential role of MPs as vectors of chemical pollutants was initially evaluated in virgin macroplastics, beached macro- and microplastics; laboratory experiments further characterized adsorbing kinetics of pyrene and cadmium on polyethylene (PE) and polystyrene (PS) MPs, and their capability to transfer adsorbed pyrene to mussels Mytilus galloprovincialis. In these organisms, several molecular, biochemical and cellular effects were analyzed in term of immunological responses, lysosomal alterations, peroxisomal proliferation, antioxidant and neurotoxic effects, genotoxicity and gene expression profile. A new protocol for extraction and FT-IR characterization of MPs in marine organisms was optimized and applied to several species of Mediterranean fish and invertebrates. Load of PAHs was higher in weathered and micron-sized particles, and an efficient adsorption of chemicals was confirmed with a time- and dose-dependent trend for both PE and PS. Histological analyses revealed occurrence of ingested MPs in haemolymph, gills and digestive tissues of mussels. Adsorbed PAHs were desorbed from MPs and bioavailable for mussels that showed many altered several molecular and cellular biomarkers. The developed extraction protocol allowed to demonstrate the presence of MPs in the stomach and, for the first time, in liver of exposed Mugil cephalus. Field studies highlighted the occurrence of MPs in 38% of analyzed wild organisms, mostly represented by fragments and lines, while PE, PS and nylon were the dominant polymers. In conclusion, this thesis provides new insights on the ecotoxicological risks of MPs for marine organisms and an important baseline for assessing the level of MPs contamination in Mediterranean biota
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Mostafa, Wael M. Abdel-Mageed. "Investigations of secondary metabolites from marine organisms." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Online version available for University member only until Sep. 1, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=53365.
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Lam, Chi-wah. "Antibacterial effects of nanoparticles on cariogenic organisms /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31490414.
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Lock, Malcolm William. "Studies of Proteins from Extremophilic Micro-organisms." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485113.
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Organisms from extreme environments have adapted to multiple stress factors induced by the local environment. The use of micro-:organisms from these environments can provide novel insights into cell and macromolecule function. Two such studies are presented in this thesis. . Firstly the tolerance of elevated magnesium chloride concentrations by the extreme halophile, Haloferax volcanii, which was isolated from the Dead Sea. The saturating salt conditions expose the Archaeon to 2.0 M MgCh and 2.1 M NaCI. The resultant osmotic pressure across the cell membrane is stabilised by saline equivalence in the cytoplasm. The role of the magnesium transport protein CorA is investigated for its role in magnesium homeostasis through the construction of a corA- knockout mutant and the development of a method to measure the intracellular Mg2+ concentrations ofH.fx. volcanii cells. Additionally the crystal structure of alanine dehydrogenase from the marine psychrophile Shewanella PA43 is compared against the model of the mesophilic enzyme from Vibrio proteolyticus, which shows high amino acid identity (77%). In this manner the comparison may highlight reasons for individual substitution events between the two enzymes that cannot be explained by current theories on protein cold adaptation. This type of analysis permits the assignment of functions for the presence/absence of specific amino acids which can be overlooked by gene alignments.
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Zelmer, Carla Dale. "Root-associated organisms of the Cypripedioideae (Orchidaceae)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65843.pdf.
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Connolly, Helen. "The formation of halocarbons by marine organisms." Thesis, Bangor University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280676.
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Phipps, Richard K. "Natural products from marine derived micro-organisms." Thesis, University of Canterbury. Chemistry, 2002. http://hdl.handle.net/10092/5796.
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A large number of micro-organisms were cultured from marine substrates collected from multiple sites along the coast of the South Island of New Zealand. Depending on growth rate and colony morphology the micro-organisms were classified as terrestrial, facultative marine or obligate marine. Micro-organisms were selected for large scale culture and extraction based on either apparent unusual morphology or observed cytotoxicity in small scale extracts.
Two very pale yellow compounds were isolated from cytotoxic extracts prepared from culture broths of a Fusarium sp. The first compound (A) was identified as a novel trichothecene called 4-deacetoxy-8-isobutyrylneosolaniol. The second compound (B) was identified as the 4-hydroxy derivative of A, previously only known through semisynthetic preparation.
The known compound cephalochromin (C) was purified from the culture broths of two unidentified Cephalosporium-like Hyphomycetes. The identity with cephalochromin was confirmed by comparison of published NMR and circular dichroism spectroscopy. An intense yellow compound was isolated from an extract prepared from culture broths of an Alternaria sp. This compound was identified by NMR spectroscopy as a novel altersolanol called altersolanol J (D).
The known compound 1-hydroxyaclacinomycin T (E) was isolated from the culture broths of a Streptomyces sp. A further five related compounds (F - J) were also isolated the culture broths. Compounds F and G, were shown by NMR spectroscopy to be stereo isomers of pyrromycin called 9-epi-pyrromycin and (7R*9R*1OR*)-pyrromycin respectively. The low isolated mass of compound H prevented a complete identification but was tentatively assigned by NMR spectroscopy as an N-demethyl derivative of pyrromycin. Compounds I and J were both shown by NMR spectroscopy to be novel pyrromycin derivatives called 1-hydroxyauramycin T and 1-hydroxysulfurmycin T respectively.
The known compounds actinomycin V (K), actinomycin Xo (L) and actinomycin D (M) were purified from extracts of the culture broths of three Streptomyces sp.
The identities of all these compounds were established by 1D and 2D NMR spectroscopy and comparison to previously reported data.
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Li, Shangxiao. "Bioactive compounds from New Zealand marine organisms." Thesis, University of Canterbury. Chemistry, 1988. http://hdl.handle.net/10092/7314.
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Primary screening of recent collections from the sea around New Zealand revealed a wide range of bioactivities, including antitumour, antiviral and anti-HIV activities. Seven marine organisms, including sponges and an ascidian, were examined to identify the active compounds responsible for these three type of biological activities.
A chemical screening protocol was established for the dereplication and prioritization of antiviral natural product extracts, which was also applied to extracts with other bioactivities. A recent modification included HPLC analysis of the eluates from solid phase extraction cartridges, coupling the UV profiles of the corresponding peaks in the HPLC traces with MarinLit database. Extracts from two marine sponges which contained known cytotoxic compounds, pateamine and calyculins respectively, were used to test the efficiency of the modified protocol. These two types of active compounds were quickly identified by searching the UV data field in MarinLit.
HIV -inhibitory activity was recognised in both aqueous and organic extracts from a sponge Chondropsis kirkii. The aqueous extract was processed on a Sephadex-25 column. The positive results of a toluidine blue test on the resultant fractions suggested that sulphated polysaccharides may be responsible for the potent anti-HIV activity. The
HIV -inhibitory components in the organic extract turned out to be a mixture of sterols. However, an increase of the cytotoxicity with increasing sample purity was also observed.
Examination of a sponge Callyspongia irregularis resulted in the isolation of a known compound, mycalamide A, which is a potent antiviral agent. Purification of the trace amount of compound obtained was mainly achieved by high speed countercurrent chromatography (HSCCC). Examination of another Callyspongia species has led to the discovery of a potently cytotoxic fraction (IC₅₀ 11 ng/mL).
A New Zealand deep water sponge, Lamellomorpha strongylata, has turned out to be a rich source of bioactive compounds. Bioassay-guided analysis led to the separation of five new cytotoxic theonellapeptolides IIIa, IIIb, IIIc, IIId and IIIe (molecular-weight 1376-1453). These tridecapeptides were characterised by amino acid analysis using GC-MS, sequencing the ring-opened peptides with FABMS-MS, and ID (¹H, ¹³C, DEPT and decoupling experiment) and 2D (COSY, TOCSY, HMQC-TOCSY, HMBC, HSMQC and ROESY) NMR, IR analysis and chemical reaction. Of these, the MS-MS technique played a very important role in sequencing. These compounds exhibited weak cytotoxicity. However, the other member of the theonellapeptolide family showed ion-transport properties.
The absolute stereochemistry of IIIe was determined by X-ray crystal structure analysis in conjunction with a chiral HPLC method. The solution conformations of IIIb and IIIe were established mainly by correlations in the ROESY spectra. Six optically pure N-methyl amino acids were synthesised for a study of the stereochemistry of the component amino acids. The absolute stereochemistry of IIIa, IIIb, IIIe and IIId were determined by chiral LC-MS analysis. In addition, three minor components were isolated from the same sponge. ¹H NMR spectra showed that they all contained peptide components.
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林志華 and Chi-wah Lam. "Antibacterial effects of nanoparticles on cariogenic organisms." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45007743.
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Fasthén, Patrick. "Diachronic Identity : Temporal Plasticity of Functional Organisms." Thesis, Högskolan i Skövde, Institutionen för kommunikation och information, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-6550.
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Eliminative materialism is a view that has been sparsely acknowledged and often overlooked when it comes to providing us with a criterion of what it takes for you and me to persist over time. This owes much to its counterintuitive belief in the non-existence of folk-psychological notions, such as persons. Against a backdrop of philosophical and scientific inquiry, this paper amounts to providing such a criterion in the form of f-organisms, taking a different route based on emergent descriptions, instead of conventional reductive explanations. The temporal plasticity (change over time) of such f-organisms display stable persistence conditions despite their constant state of reconstruction. What informs the question of identity in such a paradigm is dealt with accordingly, and the notion of the self is put in a context in which it can no longer be said to be the self we are familiar with – a context in which the center fails to hold. The imperative question for any of such criteria will be to accommodate the concept of identity as unconstrained and far away from uncertainty as possible. The main theme will thus be to reassess the general notion of diachronic identity to include our identity over time, and make explicit the various implications for such a view.
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Welburn, Susan Christina. "The rickettsia-like organisms of Glossina spp." Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240341.
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Schutte, Mart-Alet (Martha Aletta). "Molecular characterization of Sulfobacillus and related organisms." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53753.
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Thesis (MSc)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Thirteen Sulfobacillus strains from different geographical locations and two Alicyclobacillus strains were included in this study. These organisms proved to be moderately thermophillic (two different sets of optimal temperatures of 45°C and 55°C were found), Gram-positive, endospore forming bacteria. The pH optima of the strains tested was pH 2.5 and the pH range lay between pH 1.5 and pH 5.0. It was established that some strains of Sulfobacillus had the capacity for anaerobic growth when using ferric iron as an electron donor. It was determined that S. thermosuljidooxidans was the species found within South African biooxidation plants. Plasm ids were identified within strain 611 (S. thermosuljidooxidans) isolated from a Billiton commercial plant. The sample of Sulfobacillus strains used in this study could clearly be divided into two groups based on the analysis of their 16S rRNA gene sequences as well as the number of ribosomal (rm) operons present as determined by Southern hybridization. A system for the convenient identification of Sulfobacillus species was developed using several of the techniques employed in this study. Preliminary identifications can be obtained by restriction enzyme digestion of the PCR amplified 16S rRNA gene. Confirmation of this placement can be done by comparison of the 16S - 23S rRNA spacer region amplification band sizes. Once the preliminary identification has been completed it is possible to place the isolate in the correct species by making use of the differences in sugar utilization that the species exhibit. The more laborious method of 16S rRNA sequence comparisons can be undertaken if there is still any uncertainty as to which species an isolate belongs to. Phylogenetic results obtained from the 16S rRNA gene sequence indicates that the genus Sulfobacillus should probably be divided into two individual genera. Further information gathered from the phylogenetic comparisons indicates that strain Riv-14 previously assigned to S. ambivalens is more closely related to S. montseratensis. Data obtained from 16S - 23S rRNA spacer region analysis confirms this result. Future work includes the use of DNA-DNA hybridization studies and mol% G+C ratio's in order verify the presence of two distinct genera as well as placing Riv-14 within the correct species.
AFRIKAANSE OPSOMMING: Dertien isolate van die genus Sulfobacillus afkomstig van geografies verskillende areas en twee isolate van die genus Alicyclobacillus is in die studie ingesluit. Hierdie organismes het gewys dat hulle gematigde termofiele (twee verskillende groepe met optimale temperature van 45°C en 50°C elk was waargeneem), Gram-positiewe, endospoorvorrnende organismes is. Die pH optima van die isolate was pH 2.5 en die reeks van pH waar groei moontlik was het tussen pH l.5 en pH 5.0 gelê. Dit was bewys dat sekere van die Sulfobacillus isolate oor die vermoë beskik het om anaerobies te respireer deur ferri yster (Fe3+) as elektron akseptor te gebuik. Dit was bepaal dat S. thermosulfidooxidans die spesies is wat teenwoordig was in die bio-oksidasie reaktors in Suid Afrika. Plasmiede vanuit die isolaat 611 (s. thermosulfidooxidans) afkomstig vanuit 'n Billiton komersieële reaktor, is geidentifiseer. Die toetsmonster van Sulfobacillus isolate gebruik in hierdie studie het duidelik daarop gewys dat daar twee groepe binne Sulfobacillus is. Hierdie stelling is gebaseer op data afkomstig van die analiese van die 16S rRNA volgorde asook die aantal ribosomale (rm) kopieë teenwoordig soos bepaal deur Southern klad eksperimente. 'n Sisteem vir die maklike identifikasie van Sulfobacillus spesies is ontwerp deur van verskeie tegnieke, soos in hierdie studie toegepas, gebruik te maak. Aanvanklike identifikasie kan verkry word deur gebruik te maak van restriksie ensiem vertering van PKR geamplifiseerde 16S rRNA geen. Hierdie plasing van die isolaat kan bevestig word deur die grootte van die 16S - 23S rRNA intergeniese amplifikasie produkte te vergelyk. Sodra die aanvanklike plasing van die isolaat voltrek is, kan daar van die verskille in die vermoëns van die spesies om sekere suikers the benut, gebruik gemaak word om die isolaat binne die regte spesies te plaas. Die meer werksintensiewe metode van 16S rRNA volgorde vergelyking kan gebruik word indien daar enige onsekerheid is oor by watter spesies die isolaat hoort. Filogenetiese resultate verkry van die vergelyking van die 16S rRNA geen volgorde dui daarop aan dat die genus Sulfobacillus waarskynlik uit meer as een genus bestaan. Die filogenetiese data dui verder daarop dat die isolaat Riv-14 wat as 'n S. ambivalens geklassifiseer is, nader verwant is aan die spesies S. montseratensis. Data verkry vanaf die 16S - 23S intergeniese gebied analiese bevestig hierdie resultaat. Toekomstige werk sluit DNA-DNA hibridisasie en mol% Gte ratio eksperimente in om sodoende die teenwoordigheid van meer as een genus sowel as die plasing van Riv-14 in die korrekte spesies te bevestig.
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Ziehm, Matthias Fritz. "Computational biology of longevity in model organisms." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648888.
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Dandachi, Iman. "Multi drug resistant organisms in Lebanese livestock." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0286/document.
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De nos jours, l'épidémiologie des bactéries multi-résistantes a évolué et ne se limite plus aux milieux hospitaliers. En effet, les animaux sont désormais considérés comme d’importants réservoirs de bactéries multi-résistantes, notamment des Bacilles à Gram négatif sécréteurs de bêta-lactamases et/ou résistant à la colistine. L'émergence de ces bactéries chez les animaux est due principalement à l’utilisation excessive d’antibiotiques en tant que prophylaxie et facteurs de croissance. Le transfert d’organismes multi-résistants aux antibiotiques provenant d’animaux vers les humains est un problème majeur pouvant entrainer de graves infections. La transmission zoonotique se fait par contact direct/indirect mais aussi par voie environnementale. Au Liban, plusieurs études ont été menées dans les hôpitaux et ont montré une prévalence élevée de bactéries multi-résistantes. En revanche, ces études sont rares dans le milieu vétérinaire. Le but de ce travail de thèse est de décrire l'épidémiologie des organismes multi-résistants dans les animaux d’élevage destinés à la consommation au Liban. Le typage des bactéries par MLST et le séquençage du génome entier ont été utilisés pour décrire la prévalence des organismes multi-résistants et les mécanismes de résistance chez les souches isolées. Nous pouvons ainsi conclure que les élevages de poulets et de porcs sont de puissants réservoirs de gènes de résistance BLSE et mcr-1 au Liban. La dissémination de la résistance semble être polyclonale et liée à la propagation de plasmides porteurs de gènes de résistance. Par conséquent, l'utilisation de la colistine en médecine vétérinaire au Liban doit être interditeNowadays, the epidemiology of multi-drug resistance has changed and is no more confined to the hospital settings. Food producing animals are increasingly regarded as potent reservoirs of multi-drug resistant organisms i.e. beta lactamase producers and colistin-resistant Gram-negative bacilli. The emergence of multi-drug resistance in animals is thought to be mainly driven by the overuse of antibiotics as growth promoters and prophylaxis. The dissemination of resistant organisms in animals is sparked by the concern of being transferred to humans where they can be candidates for infections with limited therapeutic options. The zoonotic transmission of resistant organisms from animals to humans occurs mainly via direct/indirect contact but also via environmental routes. In Lebanon, several studies were conducted in hospitals and showed a high prevalence of multi-drug resistance; unlikely, these studies are scarce in animals. The aim of this thesis research was thus to describe the epidemiology of multi-drug resistant organisms in Lebanese Livestock Multi-locus sequence typing and whole genome sequencing were used to describe the prevalence of multi-drug resistant organisms and the corresponding mechanisms of resistance in the isolated strains from chicken, pigs, farmers and environment. Chicken and swine farms showed to be potent reservoirs of ESBL and mcr-1 genes in Lebanon. The dissemination of multi-drug resistance appears to be multi-clonal and related to the spread of plasmid carrying resistance genes. Colistin use in veterinary medicine in Lebanon should be banned
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Hidas, Eszter Zsofia. "The patterns of abundance and demography of rocky intertidal marine invertebrates indicate that recruitment can set geographical range limits." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080917.090811/index.html.
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Ahmed, Mansoor. "Numerical simulations of micro-organisms in shear flows." Thesis, KTH, Mekanik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31044.
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Tischler, Mark. "Secondary metabolites from selected British Columbian marine organisms." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26650.
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The two purine alkaloids, phidolopin (36) and desmethylphidolopin (37), originally isolated from Phidolopora pacifica, were synthesized in order to produce sufficient quantities of the natural products for extended biological and pharmacological screening and to confirm the previous structural assignment of 37 which was based on spectral data.
Various combinations of phidolopin (36), desmethylphidolopin (37), 4-hydroxymethyl-2-nitrophenol (38) and 4-methoxymethyl-2-nitrophenol (39) were isolated from four different species of bryozoans, Diaperoecia californica, Heteropora alaskensis, Tricellaria ternata and Hippodiplosia insculpta. A dietary origin is suggested for these metabolites. The red sponge, Anthoarcuata graceae yielded six novel steroids including the ∆⁴-3,6-diketosteroids 116, 117, the A-nor steroids anthosterone A (118) and anthosterone B (119) as well as two diosphenol containing steroids, 120 and 121. The proposed structures were based on a combination of spectral analysis, chemical interconversions, synthesis, and single crystal X-ray diffraction analysis.Science, Faculty of
Chemistry, Department of
Graduate
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Teo, Jason T. W. Information Technology & Electrical Engineering Australian Defence Force Academy UNSW. "Pareto multi-objective evolution of legged embodied organisms." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Information Technology and Electrical Engineering, 2003. http://handle.unsw.edu.au/1959.4/38682.
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The automatic synthesis of embodied creatures through artificial evolution has become a key area of research in robotics, artificial life and the cognitive sciences. However, the research has mainly focused on genetic encodings and fitness functions. Considerably less has been said about the role of controllers and how they affect the evolution of morphologies and behaviors in artificial creatures. Furthermore, the evolutionary algorithms used to evolve the controllers and morphologies are pre-dominantly based on a single objective or a weighted combination of multiple objectives, and a large majority of the behaviors evolved are for wheeled or abstract artifacts. In this thesis, we present a systematic study of evolving artificial neural network (ANN) controllers for the legged locomotion of embodied organisms. A virtual but physically accurate world is used to simulate the evolution of locomotion behavior in a quadruped creature. An algorithm using a self-adaptive Pareto multi-objective evolutionary optimization approach is developed. The experiments are designed to address five research aims investigating: (1) the search space characteristics associated with four classes of ANNs with different connectivity types, (2) the effect of selection pressure from a self-adaptive Pareto approach on the nature of the locomotion behavior and capacity (VC-dimension) of the ANN controller generated, (3) the effciency of the proposed approach against more conventional methods of evolutionary optimization in terms of computational cost and quality of solutions, (4) a multi-objective approach towards the comparison of evolved creature complexities, (5) the impact of relaxing certain morphological constraints on evolving locomotion controllers. The results showed that: (1) the search space is highly heterogeneous with both rugged and smooth landscape regions, (2) pure reactive controllers not requiring any hidden layer transformations were able to produce sufficiently good legged locomotion, (3) the proposed approach yielded competitive locomotion controllers while requiring significantly less computational cost, (4) multi-objectivity provided a practical and mathematically-founded methodology for comparing the complexities of evolved creatures, (5) co-evolution of morphology and mind produced significantly different creature designs that were able to generate similarly good locomotion behaviors. These findings attest that a Pareto multi-objective paradigm can spawn highly beneficial robotics and virtual reality applications.