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Dai, Zhenhui. "Experimental study of fluid flow and heat transfer in tortuous microchannels." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/11596.
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Tortuous microchannels have attracted increasing interest due to great potential to enhance fluid mixing and heat transfer. While the fluid flow and heat transfer in wavy microchannels have been studied extensively in a numerical fashion, experimental studies are very limited due to the technical difficulties of making accurate measurements in micro-scale flows. This thesis provides insights into thermohydraulics of tortuous microchannels by developing experimental techniques and performing systematic visualisation and heat transfer experiments. The detailed flow patterns (including Dean vortices) and transition behaviours in wavy channels are successfully identified using Micro-Particle Image Velocimetry (micro-PIV) and 3D reconstruction techniques. Conjugate heat transfer simulations are carried out to understand the complex thermal behaviour present in the current experimental design and to validate and compare with experimental results. The impact of tortuous geometry on flow and heat transfer in microchannels is studied systematically. The high quality experimental data provide a new perspective on flow behaviour and heat transfer performance in wavy microchannels. In addition, the stackability of channels on a plate is considered. The zigzag pathways are found to provide the greatest heat transfer intensification based on a plate structure. A significant component of the research in this thesis has been the development of experimental techniques to measure local heat transfer rates in microchannels. A two-dye laser induced fluorescence (LIF) technique using temperature sensitive particles (TSPs) is developed with promising characteristics for local temperature measurement and the capability for simultaneous measurement of temperature and velocity fields in microscale systems. The advanced experimental techniques developed in this thesis provide important tools for the investigation of thermohydraulics of various micro-devices in the field of engineering.
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Großberger, Sandra [Verfasser], and Geoffrey [Gutachter] Lee. "Tortuous membranes produced by vacuum-induced surface directional freezing / Sandra Großberger ; Gutachter: Geoffrey Lee." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://d-nb.info/1130869555/34.
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Thieu, Lam Mai. "Multiscale Tortuous Diffusion in Anion- and Cation-Exchange Membranes: Exploration of Counterions, Water Content, and Polymer Functionality." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/88849.
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Fundamental understanding of water transport and morphology is critical for improving ion conductivity in polymer electrolyte membranes (PEMs). Herein, we present comprehensive water transport measurements comparing anion-exchange membranes (AEMs) based on ammonium-functionalized poly(phenylene oxide) and cation-exchange membranes (CEMs) based on sulfonated poly(ether sulfone). We investigate the influence of counter ions, alkyl side chain, and degree of functionalization on water transport in AEMs and CEMs using pulsed-field-gradient (PFG) NMR diffusometry. Water diffusion in both AEMs and CEMs exhibit specific trends as a function of water uptake (wt%), indicating morphological similarities across common chemical structures. Furthermore, restricted diffusion reveals micron-scale heterogeneity of the hydrophilic network in both CEMs and AEMs. We propose a model wherein the hydrophilic network in these membranes has micron-scale distributions of local nm-scale dead ends, leading to changes in tortuosity as a function of water content, counterion type, and polymer structure. We furthermore parse tortuosity into two regimes, corresponding to nm-to-bulk and µm-to-bulk ranges, which reveal the importance of multi-scale morphological structures that influence bulk transport. This study provides new insights into polymer membrane morphology from nm to µm scales with the ultimate goal of controlling polymeric materials for enhanced fuel cells and other separations applications<br>MS
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Snape, Holly Amelia. "The evolution of a tortuous relationship : the transformation of Chinese state-society relations explored through grassroots NGOS." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702273.
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This thesis examines the ongoing transformation of China's state-society relationship by exploring the changing roles of, and relationships between, the state and grassroots NGOs. It is based on findings from over a year of empirical research undertaken at grassroots NGOs; thorough readings of core Party and government documents to investigate changes in attitudes from the top; and my subsequent work with many of these social actors over the years after my initial research period, adding a temporal dimension (2011-2015) to the study. Extended periods of participant observation allowed me to examine the finest details of the work of grassroots NGOs and their relationships with local state bodies, enabling me to develop an understanding of 'the quiet approach', which, I argue, is important in shaping the transformation of the state-society relationship. Analysis of past and recent state documents and institutions helped me to frame the behaviour of NGOs within the macro context of the transforming attitude of the state towards social organizing and society governing society. The temporal dimension was crucial in discerning the wave-like fluctuations that I found to characterize the transformation of the state-society relationship. Existing research often adopts either a bottom-up approach, viewing change as being created by social forces, or a top-down approach, viewing state forces as limiting, controlling and manipulating change. Ultimately, this thesis argues that the transformation" of the state-society relationship is a combination of these forces reacting to and engaging with one another: as state attitudes fluctuate, NGOs can respond by tempering their behaviour; by tempering their behaviour and laying low during times of 'down-waves' they incrementally build their own capacity, making themselves increasingly necessary to the state; through acting' quietly' they encourage the state to trust them; and as the state trusts and needs them more, NGOs become more irreversibly integrated into service provision and governance.
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Hertzberg, Alice. "The readmission agreement between Sweden and Afghanistan : A tortuous strategy of creating a deportation corridor to a war-torn country?" Thesis, Malmö universitet, Malmö högskola, Institutionen för globala politiska studier (GPS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-40379.
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Focusing on the readmission agreement between Sweden and Afghanistan, this study aims to enhance our understanding of why and how states use readmission agreements and the discourse underpinning these practices. Based on interviews with key officials working in the Swedish deportation infrastructure, the findings show that the agreement is presented as a successful measure resulting in a more predictable process and increased forced returns. The agreement is a critical technique for minimizing disruptions in the deportation corridor to Afghanistan, however, not without interruptions due to the infrastructure’s reliance on many elements and the complexity of bilateral cooperation. The discursive practices, including “problem” representations and assumptions justifying the agreement, can be questioned considering that most Afghans abscond or travel to another Schengen country instead of returning. The absence of an agreement evaluation further necessitates calling the increased governmental focus on readmission agreements into question. The study contributes to deconstructing governmental rationalities through a novel methodology of studying deportation and readmission.
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Hernández, Luján Àngel. "Les tortugues (Testudines) del neogen i quaternari de Catalunya (NE de la Península Ibèrica)." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/381065.
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Es revisa el registre neogen i quaternari de les tortugues terrestres i d’aigua dolça (Testudines) de Catalunya, a partir de les restes de la conca del Vallès-Penedès i del pla de Barcelona. A banda d’una revisió bibliogràfica, l’estudi es fonamenta en la descripció i atribució taxonòmica de més de 1.400 restes fòssils (majoritàriament inèdites) procedents de més de 100 localitats. S’emfatitzen aquelles restes que permeten un avenç més significatiu en el coneixement de la sistemàtica, filogènia i/o biostratigrafia de determinats tàxons extints.
Respecte a les tortugues terrestres gegants, destaca la descripció dels dos primers cranis coneguts del testudínid Titanchelon richardi (anteriorment Cheirogaster), els quals permeten diferenciar adequadament aquesta espècie de Titanchelon bolivari, l’altre testudínid gegant del Miocè ibèric. Es conclou que, al Vallès-Penedès, el rang estratigràfic de Ti. bolivari (MN3–MN4) no se superposa amb el de Ti. richardi (MN7+8–MN10 i, temptativament, MN6–MN12). El tàxon nominal Cheirogaster arrahonensis és considerat un nomen vanum i el seu holotip atribuït a Testudo (Chersine) sp. També es revisen tots els testudínids de mida més petita presents a la conca del Vallès-Penedès, especialment Testudo (Chersine) catalaunica (MN6–MN9), per a la qual es presenta una diagnosi esmenada i es conclou que no pertany al subgènere extint Paleotestudo. A l’espera d’un estudi més detallat del material disponible, també es reporten nombroses restes inèdites de Testudo del Miocè del Vallès-Penedès, que són atribuïdes a “Paralichelys” catalaunicus [=T. (Chersine) sp. nov., que en el futur necessitarà un nom de reemplaçament per evitar l’homonímia amb T. catalaunica] (MN3–MN4); i Testudo (C.) aff. burgenlandica (MN9–MN11). També es descriu el material clàssic i inèdit de Testudo (Chersine) lunellensis del Plistocè mitjà de Barcelona, una espècie extinta molt propera a l’actual Testudo (Chersine) hermanni. Finalment, es presenta una filogènia revisada de les espècies actuals i extintes de Testudo, que recupera les relacions entre espècies actuals indicades per les dades moleculars, i permet dividir aquest gènere en tres subgèneres actuals i un d’extint. Quant a les tortugues d’aigua dolça, se’n revisa el material publicat i inèdit del Miocè de la conca del Vallès-Penedès. Es reporta per primera vegada la presència dels gèneres Clemmydopsis i Trionyx en aquesta conca, i s’hi constata la presència de diverses espècies de geoemídids pticogasterins del gènere Ptychogaster: Ptychogaster (Temnoclemmys) batalleri (MN6–MN9); P. (Temnoclemmys) sp. (MN3–MN4); i P. (Ptychogaster) sp. (MN4 i MN7+8–MN9). A més, es proporcionen diagnosis esmenades de P. batalleri (de la qual Testudo celonica n’és un sinònim subjectiu posterior), així com dels subgèneres Temnoclemmys i Ptychogaster s.s.
En total, es constata la presència 13 espècies de testudins durant el Neogen i el Quaternari de Catalunya, a partir de l’estudi de les restes fòssils del Miocè de la conca del Vallès-Penedès i del Plistocè del pla de Barcelona. Les quelonofaunes del Miocè de Catalunya es caracteritzen per la presència de testudínids terrestres gegants (Titanchelon) i de mida més petita (Testudo), a més de tortugues d’aigua dolça de les famílies dels geoemídids (majoritàriament Ptychogaster, però també Clemmydopsis) i dels trioníquids (Tryonix sp.). Des del Miocè inferior (Ramblià i Aragonià inferior), aquestes faunes de quelonis esdevenen progressivament més riques i menys similars a les de les conques ibèriques internes durant el Miocè mitjà (Aragonià mitjà i superior), fins a assolir un màxim de diversitat en el Miocè superior (Vallesià). A partir d’aquest moment, la diversitat decreix progressivament fins al Turolià, moment a partir del qual no tenim registre fins al Plistocè, en què trobem una quelonofauna empobrida i similar a l’actual, caracteritzada per un testudínid de mida petita (Testudo lunellensis), el geoemídid actual Mauremys, i l’emídid actual Emys.<br>The Neogene and Quaternary record of tortoises and freshwater turtles (Testudines) from Catalonia is revised based on fossil remains from the Vallès-Penedès Basin and the Barcelona Plain. Besides a review of the literature, this study builds on the description and taxonomic attribution of more than 1,400 fossil remains (mostly unpublished) from more than 100 localities. The study emphasizes those remains that enable a significant advance in the systematics, phylogeny and/or biostratigraphy of certain extinct taxa.
With regard to giant tortoises, it is noteworthy the description of the two first known skulls of the testudinid Titanchelon richardi (formerly Cheirogaster), which first enable a reliable distinction between this species and Titanchelon bolivari, the other giant testudinid from the Iberian Miocene. It is concluded that, in the Vallès-Penedès, the stratigraphic range of Ti. bolivari (MN3–MN4) does not overlap that of Ti. richardi (MN7+8–MN10 and, tentatively, MN6–MN12). The nominal taxon Cheirogaster arrahonensis is considered a nomen vanum and its holotype assigned to Testudo (Chersine) sp. The smaller testudnids from the Vallès-Penedès Basin are also revised, particularly Testudo (Chersine) catalaunica (MN6–MN9), for which an emended diagnosis is presented, further concluding that it does not belong to the extinct subgenus Paleotestudo. Pending a more detailed study of the available material, numerous additional unpublished remains of other Testudo species from the Miocene of the Vallès-Penedès are reported, being ascribed to “Paralichelys” catalaunicus [=T. (Chersine) sp. nov., which in the future will need a replacement name, so as to avoid homonymy with T. catalaunica] (MN3–MN4); and Testudo (C.) aff. burgenlandica (MN9–MN11). The classical and unpublished material of Testudo (Chersine) lunellensis, an extinct species from the middle Pleistocene of Barcelona very close to the extant Testudo (Chersine) hermanni, is also described. Finally, a revised phylogeny of extant and extinct species of Testudo is provided; it recovers the relationships among extant species as indicated by molecular data, and further enables to distinguish three extant subgenera and one extinct subgenus. Regarding freshwater turtles, the published and unpublished material from the Miocene of the Vallès-Penedès Basin is revised. The presence of genera Clemmydopsis and Trionyx is first reported for this basin, where the presence of several species of ptychogasterine geoemydids is further shown: Ptychogaster (Temnoclemmys) batalleri (MN6–MN9); P. (Temnoclemmys) sp. (MN3–MN4); and P. (Ptychogaster) sp. (MN4 and MN7+8–MN9). Emended diagnoses of P. batalleri (of which Testudo celonica is a junior subjective synonym), as well as of the subgenera Temnoclemmys and Ptychogaster s.s., are further provided.
Overall, it is ascertained the presence of 13 species of testunids in the Neogene and Quaternary of Catalonia, on the basis of the study of fossil remains from the Miocene of the Vallès-Penedès Basin and the Pleistocene of the Barcelona Plain. The chelonofaunas from the Miocene of Catalonia are characterized by the presence terrestrial testudinids, both giant (Titanchelon) and smaller (Testudo), as well as that of geoemydid (mostly Ptychogaster, but also Clemmydopsis) and trionychid (Tryonix sp.) freshwater turtles. Since the early Miocene (Ramblian and early Aragonian), these faunas of chelonians have progressively become richer and less similar to those from the inner Iberian basins during the middle Miocene (middle to late Aragonian), until reaching a peak of diversity in the late Miocene (Vallesian). From then onward, their diversity progressively decreases until the Turolian, and there is a gap in the record until the Pleistocene, in which the chelonofauna is impoverished and similar to the living one, being characterized by a small testudinid (Testudo lunellensis), the extant geoemydid Mauremys, and the extant emydid Emys.
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Sjöström, Julia, and Helena Åkesson. "Investigation of Ductility Dip at 1000˚C in Alloy 617." Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209823.
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Alloy 617 displays a ductility dip during straining at exactly 1000˚C, leading to brittle fracture. A sudden decrease in ductility appearing during Gleeble hot ductility tests of Ni-based superalloys is a well-known phenomenon, while its cause is unknown. Many mechanisms have been established as possible contributors to the issue, and in later years not one, but the simultaneous presence of several of these mechanisms were confirmed as the cause. The ductility dip leads to solid state cracking and a specific solid state cracking phenomenon known as ductility dip cracking is specifically common in Ni-based superalloys. Ductility dip cracking is identified by intergranular cracks and the occurrence of specific precipitates, among other things. This work investigates the possibility that the decreased ductility is due to ductility dip cracking. Furthermore, other possible explanations are investigated. Visual examination was conducted through LOM, SEM and chemical analysis using EDS technique. Combined with thermodynamic calculations, the existence of Cr-rich M23C6 carbides, Ti(N,C) and Mo-rich particles, most likely M3B2, were confirmed. Further, it is established that the ductility dip is related to the lack of dynamic recrystallization at 1000˚C. It is not confirmed that the ductility dip in alloy 617 is due to ductility dip cracking.<br>Nickelbaslegeringen 617 uppvisar en minskning i duktilitet under Gleeble-dragprovning vid exakt 1000˚C vilket leder till sprött brott. En plötslig sänkning av duktiliteten vid varmdragning av Ni-baserade superlegeringar är ett välkänt fenomen, dock är orsaken inte fastställd. Många mekanismer har bekräftats som bidrag till problemet och under de senaste åren har den simultana närvaron av fler av dessa mekanismer bekräftats som orsaken. Sänkningen i duktilitet leder till sprickbildning i fast fas och en specifik typ av sprickbildning känd som ”ductility dip cracking” är speciellt förekommande i Ni-bas legeringar. Denna identifieras bland annat genom intergranulära sprickor och närvaron av specifika utskiljningar. Detta arbete undersöker möjligheten att duktilitetssänkningen beror på ”ductility dip cracking”. Dessutom undersöks fler tänkbara förklaringar. Visuell granskning genomfördes via LOM och SEM och analys av sammansättningar via EDS-analys. I kombination med termodynamiska simuleringar blev förekomsten av Cr-rika M23C6 karbider, Ti(N,C) och Mo-rika partiklar, troligtvis M3B2, bekräftad. Fortsatt är det bekräftat att duktilitetssänkningen är relaterat till avsaknaden av rekristallisation vid 1000˚C. Det är inte bekräftat i detta arbete att duktilitetssänkningen i legering 617 beror av ”ductility dip cracking”.
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Claude, Julien. "Contraintes et sélection au cours de l'évolution morphologique des testudinioidea ("reptilia", testudines) : approches comparatives et morphométriques." Montpellier 2, 2003. http://www.theses.fr/2003MON20025.
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Bravo, Alarcón Fernando. "El tortuoso camino del Ministerio del Ambiente." Pontificia Universidad Católica del Perú, 2008. http://repositorio.pucp.edu.pe/index/handle/123456789/47371.
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Cabrera, Pérez Miguel Angel. "Valores hematológicos de la tortuga motelo (Geochelone denticulata), mantenidos en cautiverio en la ciudad de Iquitos-Perú." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2008. https://hdl.handle.net/20.500.12672/662.
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En el Perú se han descrito 17 especies diferentes de tortugas de las cuales 15 son de vida marina o continental (en ríos o lagos) y apenas 2 especies desarrollan su vida íntegramente fuera del agua, éstas son la tortuga de patas rojas (Geochelone carbonaria) y la tortuga motelo (Geochelone denticulata). Recientemente se ha dado importancia a la realización de estudios
de campo que permitan recolectar información sobre el estado de salud de poblaciones silvestres con énfasis en aquellas especies en peligro de extinción. La evaluación hematológica es el método más recomendado a través del cual se puede obtener excelentes indicadores del estado de salud de un individuo (Owens y Ruiz, 1980; Lowell, 1998).
El campo de la hematología en reptiles es hasta cierto punto, nuevo y poco conocido. Sin embargo ha ido evolucionando, logrando así habilidad y experiencia, con más y nuevas técnicas (Wilmoth, 1994; Lowell, 1998).
Muchos factores propios del animal, como la edad, sexo, nivel de estrés, nivel nutricional, niveles hormonales e hidratación corporal, así como factores medioambientales (temperatura, estación y presión de oxigeno), afectan los valores hematológicos (Dessauer, 1970; Aguirre et al., 1995).
Existen pocos estudios sobre hematología de especies pertenecientes a los testudines en el mundo entre los que podemos mencionar a la tortuga de caja Terrapene carolina (Herber, 1970; Frye, 1986; Jackson, 1999; Raphael, 2003), tortuga verde Chelonia mydas y tortuga cabezona marina Caretta caretta (Herber, 1970; Raphael, 2003) tortuga radiada Testudo radiata (Marks y Citno, 1990; Raphael, 2003), tortuga americana Trachemys scripta elegans (Herber, 1970; Jackson, 1999), entre otros trabajos más, sin embargo, muy pocos estudios se han realizado en América Latina, entre los que podemos destacar el estudio hematológico de la tortuga terrestre argentina Chelonoidis chilensis chilensis (Troiano y Silva, 1998).
Los valores de hemograma y bioquímica sérica obtenidos para las diferentes especies de testudines son muy variados, explicables por los diferentes ecosistemas en que cada especie ha adaptado su modo de vida ya sea por el clima, altitud, tipo de alimento a su alcance y la actividad diaria que éstos realizan.
En Perú no existen registros de trabajos publicados o investigaciones relacionadas sobre hematología en tortugas, por dicho motivo se planteó este trabajo el cual tiene por objetivo, determinar los valores hematológicos de la tortuga motelo (Geochelone denticulata) en la ciudad de Iquitos.
Los valores obtenidos servirán de referencia para evaluar el estado de salud de las tortugas, así como para establecer comparaciones con los valores reportados por otros investigadores.<br>Tesis
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Ruiz, Moreno Nelson Manuel. "Identificación de Salmonella spp. en tortugas motelo (Geochelone denticulata) de un criadero de la ciudad de Iquitos, región Loreto." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. https://hdl.handle.net/20.500.12672/710.
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El objetivo del presente estudio fue detectar la presencia de Salmonella spp. en el total (n igual a 30) de la población de tortugas motelo (Geochelone denticulata) de un criadero de 25 m2 de área, construido con materiales de la misma zona y piso de tierra; la alimentación de los animales a base de frutas y verduras, agua Ad libitum y se observó presencia de roedores, la crianza se realizo en condiciones de cautiverio en la ciudad de Iquitos, Región Loreto. Las muestras de heces se obtuvieron por hisopado rectal, luego llevadas al laboratorio de la Estación Experimental IVITA-Iquitos y se colocaron en un medio de enriquecimiento Agar Soya Tripticasa para luego ser remitidas en condiciones de refrigeración a la Sección de Bacteriología y Micología del Laboratorio de Microbiología y Parasitología, de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos; para su aislamiento e identificación mediante pruebas de cultivo bacteriológico y bioquímicas. El 6.7% (2/30) de las muestras fueron positivas a Salmonella spp. Adicionalmente se encontraron otras bacterias como Escherichia coli y Pseudomona aeruginosa en un 80% (24/30), Proteus vulgaris en un 26.6% (8/30), Proteus mirabilis en 6.7% (2/30) y Citrobacter spp. 16.7% (5/30). La Salmonella spp se detectó en tortugas sanas y enfermas, además se realizó la tipificación por el método Who Global Salm Surv, obteniendo como resultado Salmonella enterica subespecie enterica serotipo typhimurium en las dos muestras positivas a dicha bacteria. Se concluye que existe presencia de Salmonella spp. (Salmonella typhimurium) en muestras de hisopados cloacales de tortugas motelo criadas en cautiverio, y que los demás microorganismos hallados forman parte de la familia enterobacteriaceae propio del tracto intestinal de éstos animales.<br>The objective of the present study was to detect the presence of Salmonella spp. in the total (n same 30) of the population of turtles motelo (Geochelone denticulata) of a hatchery of 25 m2 of area, built with materials of the same area and earth floor; the feeding of the animals with the help of fruits and vegetables, dilutes Ad libitum and presence of rodents, the upbringing one was observed I carry out under captivity conditions in the city of Iquitos, Región Loreto. The samples of grounds were obtained by rectal hisopado and then taken to the laboratory of the Experimental Station IVITA-Iquitos and they were placed in a means of enrichment Agar Soya Tripticasa for then to be remitted under refrigeration conditions to the Section of Bacteriology and Micología of the Laboratory of Microbiology and Parasitología, of the Faculty of Veterinary Medicine of the University National Major of than San Marcos; for their isolation and identification by means of bacteriological and biochemical cultivation tests. The 6. 7% (2/30) of the samples they went positive to Salmonella spp. Additionally they were other bacterias like Escherichia coli and Pseudomona aeruginosa in 80% (24/30), Proteus vulgaris in a 26. 6% (8/30), Proteus mirabilis in 6. 7% (2/30) and Citrobacter spp. 16. 7% (5/30). The Salmonella spp was detected in healthy and sick turtles, she was also carried out the tipificación for the method Who Global Salm Surv, obtaining Salmonella enterica subspecies enterica serotipo typhimurium in the two positive samples to this bacteria. You concludes that presence of Salmonella spp exists. (Salmonella typhimurium) in samples of hisopados cloacales of turtles motelo raised in captivity, and that the other found microorganisms are part of the family enterobacteriaceae characteristic of the intestinal tract of these animals.<br>Tesis
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Schell, Rebecca. "Sceletium tortuosum and Mesembrine: A Potential Alternative Treatment for Depression." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/375.
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Major depressive disorder affects people’s productivity and ability to function in everyday life. The disorder can be attributed to neurochemical imbalances of various neurotransmitters including but not limited to serotonin, dopamine, and norepinephrine. Conventional pharmacological treatments have focused primarily on these three neurotransmitters, and have been shown to be effective in alleviating most of the major symptoms of depression. Although these treatments are effective with most patients, they are known to have adverse side effects, causing patients to seek alternative treatments. Sceletium tortuosum, a succulent plant found in the Cape region of South Africa, has been shown to have anxiolytic effects when used recreationally. Studies have confirmed the presence of a family of alkaloids mesembrines that are present within the plant and believed to be responsible for the calming effects. Pharmacological analyses have revealed that individual members of the alkaloid family act as either serotonin reuptake inhibitors (SRI) or phosphodiesterase-4 (PDE4) inhibitors. The current study seeks to elucidate the antidepressant properties of the mesembrine alkaloids in a mouse model of depression. Isolated alkaloids were administered at a low dose (10 mg/kg) and a high dose (80 mg/kg) to BALB/c mice in the forced swim test a rodent model of behavioral despair. This was compared with paroxetine (Paxil) (1 mg/kg), a selective serotonin reuptake inhibitor with proven antidepressant efficacy, and 0.9% saline. Each trial of the forced swim test was administered for six minutes and the duration of swimming and immobility was measured. In order to assess any locomotor effects of the drug treatments, an open field exploration test was also employed one week following the forced swim task. Results from the forced swim test revealed a statistically significant reduction in the duration of immobility (behavioral despair) between the low dose of alkaloids and saline. No significant effects in immobility were found across the other drug treatment conditions (high dose mesembrine, paroxetine, and saline). Further, none of the treatment groups showed statistically significant locomotor interference effects in the open field exploration test. We conclude that the mesembrine alkaloids present in Sceletium tortuosum have antidepressant properties and may represent a suitable alternative for the treatment of major depressive disorder.
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Lalire, Maxime. "STAMM, un modèle individu-centré de la dispersion active des tortues marines juvéniles : applications aux cas des tortues luths du Pacifique Ouest et de l'Atlantique Nord-Ouest et aux tortues caouannes de l'ouest de l'océan Indien." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30259/document.
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Les tortues marines, espèces emblématiques des écosystèmes marins, sont de plus en plus menacées par les effets directs et indirects des activités humaines. Leur cycle de vie est complexe, partagé entre divers habitats, souvent très éloignés les uns des autres. Leur conservation nécessite donc d'identifier les habitats occupés à chaque stade de vie et les routes migratoires empruntées entre ces différents habitats. Si l'écologie spatiale des tortues adultes est relativement bien connue, notamment grâce au suivi par satellite, il n'en va pas de même pour les juvéniles qui se développent plusieurs années en milieu pélagique sans pouvoir être suivis. Dans ce contexte, les simulations numériques constituent un outil adapté pour explorer la dispersion des tortues juvéniles à partir de leurs plages de naissance. Jusqu'à présent il a le plus souvent été supposé dans ces simulations que les juvéniles dérivaient passivement avec les courants marins. Dans ce travail de thèse nous présentons STAMM (Sea Turtle Active Movement Model), un nouveau modèle de dispersion active des tortues juvéniles qui s'attache à dépasser l'hypothèse initiale d'une dérive purement passive. Dans STAMM, les juvéniles simulés se déplacent sous l'influence de la circulation océanique et d'une nage motivée par la recherche d'habitats favorables. Ce modèle est appliqué ici à l'étude de la dispersion des juvéniles de trois populations de tortues marines : les tortues luths (Dermochelys coriacea) du Pacifique Ouest et de l'Atlantique Nord-Ouest puis les tortues caouannes (Caretta caretta) de l'ouest de l'océan Indien. Nos résultats montrent que, même si la circulation océanique détermine, à grande échelle, les zones de dispersion, la prise en compte des mouvements motivés par l'habitat augmente considérablement le réalisme des simulations et impacte profondément la distribution spatiale et temporelle des individus simulés à l'intérieur de leur zone de dispersion. Les mouvements motivés par l'habitat induisent notamment des migrations saisonnières en latitude qui réduisent la mortalité par hypothermie. Ces mouvements induisent également une concentration des individus simulés dans des zones productives (comme les upwellings de bord Est) inaccessibles en dérive passive. Ces résultats questionnent la vision classique des juvéniles circulant passivement autour des gyres océaniques et devraient rapidement être pris en compte pour la mise en place de mesures de conservation ciblées visant les tortues marines juvéniles<br>Sea turtles are increasingly threatened by the direct and indirect effects of human activities. Their life cycle is complex, shared between various, and often very distant, habitats. Their conservation therefore requires identifying the habitats occupied at each stage of life and the migration routes between these different habitats. While the spatial ecology of adult turtles is relatively well known, particularly through satellite monitoring, the situation is not the same for juveniles which pelagic development phase remains largely unobserved. In that context, numerical simulation constitutes an appropriate tool to explore the dispersal of juvenile sea turtles from their natal beaches. Until now, simulations were mostly performed under the assumption that juveniles disperse passively with oceanic currents. In this PhD thesis we present STAMM (Sea Turtle Active Movement Model), a new model of active dispersal that aims to go beyond the initial hypothesis of passive drift. In STAMM, juvenile sea turtles move under the influence of ocean currents and swimming movements motivated by the search for favorable habitats. This model is applied here to the study of the dispersal of juveniles from three sea turtle populations: leatherback turtles (Dermochelys coriacea) of the Western Pacific and the Northwest Atlantic Oceans, and loggerhead turtles (Caretta caretta) of the Western Indian Ocean. Our results show that, although ocean currents broadly shape juvenile dispersal areas, simulations including habitat-driven movements provide more realistic results than passive drift simulations. Habitat-driven movements prove to deeply structure the spatial and temporal distribution of juveniles. In particular, they induce seasonal latitudinal migrations that reduce cold induce mortality. They also push simulated individuals to concentrate in productive areas that cannot be accessed through pure passive drift. These results challenge the classical view of juveniles circulating passively around oceanic gyres. They should rapidly be taken into account for the implementation of targeted conservation measures concerning juvenile sea turtles
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Campos, Pena Patricia. "Ecología trófica y análisis del grado de omnivoría de las tortugas verdes en la costa atlántica occidental = Trophic ecology and analysis of the degree of omnivory of the green turtles on the Western Atlantic Coast." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/668248.
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Los hábitats utilizados por las tortugas marinas durante su desarrollo varían notablemente en cuanto a características ambientales y disponibilidad de alimento. Comprender los factores que determinan la selección del hábitat y de la dieta resulta esencial para comprender la interacción que existe entre dichas especies y sus hábitats. Dicho conocimiento también proporciona datos para adoptar medidas de gestión y conservación destinadas a restaurar y mantener las poblaciones de tortugas marinas y así, su función ecológica en el ecosistema. Las zonas costeras de Brasil, Uruguay y Argentina albergan diversos hábitats de importancia para la alimentación de los juveniles de la tortuga verde, pero todavía existe un gran desconocimiento sobre la ecología trófica de esta especie durante la fase juvenil de transición desde hábitats pelágicos a bentónicos. En esta tesis se ha estudiado cómo se produce el asentamiento de las tortugas verdes en la costa de Brasil, incluyendo la selección del hábitat y la adquisición de un microbioma adecuado para la digestión de material vegetal. Los resultados demuestran que el asentamiento de las tortugas verdes a lo largo de la costa oriental de Sudamérica está fuertemente influido por la corriente del Brasil y que el cambio ontogenético es rápido en las zonas tropicales y más lento en las subtropicales, a pesar de la rápida adquisición de una microbiota capaz de degradar polisacáridos complejos en ambas zonas. Dicha microbiota resulta en una gran eficiencia en la digestión de algas, especialmente de las Rodophyta, pero no impide la digestión de presas animales. Por último, las tortugas juveniles seleccionan de forma preferente para su alimentación zonas de arrecife de baja rugosidad, someras y con poco coral vivo.<br>The habitats used by marine turtles during their development vary largely in environmental conditions and food availability. Understanting habitat selection is critical to the implementation of successful management and conservation actions aiming to restore and maintain sea turtle populations and, thus, their ecological function in the ecosystem. The coastal areas of Brazil, Uruguay and Argentina have a diversity of coastal habitats supporting feeding grounds for the green turtle, but there is still a lack of knowledge about the feeding ecology of this species during the juvenile transition phase from pelagic habitats to neritic habitats. This thesis has studied the settlement of green turtles in the coastal habitats of Brazil, including the ontogenetic diet shift. Results show that the settlement of green turtles along the eastern coast of South America is strongly influenced by the Brazilian current and that the ontogenetic change is fast in the tropics and slower in the subtropics, despite a fast acquisition of a microbiota capable of fermenting complex polysaccharides shortly after settlement. Such microbiome is highly efficient for the digestion of macroalgae, particularly Rodophyta, but does not impede the digestion of animal matter. Finally, preferred foraging grounds are shallow, have a low rugosity and little live coral.
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Baboulin, Stéphanie Ducos de Lahitte Jacques. "La fibropapillomatose chez les tortues marines état actuel des connaissances /." [S.l.] : [s.n.], 2008. http://oatao.univ-toulouse.fr/2755/1/sautier_2755.pdf.
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Brito, Carrasco Beatriz Daniela. "Descripción de algunos aspectos hematológicos y bioquímicos sanguíneos de la colonia de tortuga negra (Chelonia mydas) establecida en Bahía Salado, región de Atacama." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/142729.
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Memoria para optar al Título Profesional de Médico Veterinario<br>En años recientes se han establecido algunos valores de referencia para variables hematológicas en los quelonios de vida libre. Debido a que los valores bioquímicos y hematológicos de tortugas marinas además de variar según la genética, madurez, sexo, y estado migratorio, pueden variar con la localización geográfica, hábitat y dieta se recomienda realizar estudios que lleven a establecer valores basales en cada sitio de congregación. Por lo cual obtener valores hematológicos basales de las tortugas que llegan a las costas chilenas permitiría un mayor grado de conocimiento y asertividad en las decisiones y estrategias de conservación para la especie. El objetivo de la presente memoria de título fue describir algunos aspectos hematológicos y bioquímicos sanguíneos de la población natural más austral conocida de tortuga negra (Chelonia mydas) establecida en Bahía Salado, Región de Atacama, y así contribuir al conocimiento del estado sanitario de los individuos que la conforman. Se analizó extendidos sanguíneos en búsqueda de hemoparásitos y se midió el hematocrito y 17 variables de bioquímica sanguínea en los 7 individuos de C. mydas capturados. Los individuos muestreados corresponden en su mayoría a hembras adultas (n=5) y en menor proporción a juveniles de sexo indeterminado (n=2). La totalidad de individuos se presentó sano al examen clínico realizado por el médico veterinario a cargo. Las muestras sanguíneas fueron obtenidas desde la vena yugular externa inmediatamente luego de la captura para reducir el estrés. Las muestras fueron procesadas y almacenadas en terreno para luego ser transportadas al Laboratorio de Hematología y Bioquímica Clínica de la Facultad de Ciencias Veterinarias y Pecuarias de la Universidad de Chile, donde fueron analizadas. Una vez obtenidos los resultados, se calculó la media, desviación estándar y la mediana y se reportaron los valores mínimos y máximos para cada variable considerando las muestras en su conjunto pero no intervalos de confianza debido al bajo n. El volumen globular aglomerado y la proteína plasmática total se encontraron dentro de los valores de referencia utilizados para C. mydas en otras partes del mundo. Los rangos estrechos obtenidos para proteína total, albumina, globulinas, glucosa, ácido úrico, calcio, fosforo y bilirrubina total se podrían deber al número bajo de muestras. La evaluación de los extendidos sanguíneos en búsqueda de hemoparásitos determinó que no existe presencia de estos. El número de muestras utilizadas en el presente
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estudio fue de 7 individuos diferentes, lo cual no permitió realizar comparaciones estadísticamente significativas. Esto indica que se debe seguir trabajando en el área para así incrementar el n y poder obtener rangos de referencia para la colonia que sean estadísticamente significativos. En conclusión, tomando en cuenta los resultados obtenidos para las variables de hematología, bioquímica sanguínea y evaluación de la presencia de hemoparásitos, en conjunto con los resultados del examen clínico externo de las tortugas de Bahía Salado, es posible sugerir que es una colonia sana y que los resultados sanguíneos encontrados en el presente estudio serían propios de esta colonia debido al tipo hábitat, a la alimentación disponible (tipo y abundancia) y a la estructura sexual y etaria de los individuos que la conforman.<br>In recent years some reference values have been established for hematological variables in chelonians. The biochemical and hematological values vary according to the genetics, maturity, sex, and immigration status. Also they may vary with the geographic location, habitat and diet. Therefore is recommended to carry out studies that establish reference values in each congregation site. For that reason obtaining biochemical and hematological reference values of the sea turtles that inhabits the Chilean coasts is important as that would provide a greater degree of knowledge and assertiveness in the conservation decisions and strategies for the species. The objective of the present study was to describe some hematological and biochemical aspects of the most austral known natural stock of black turtle (Chelonia mydas) established in Bahía Salado, Atacama Region, and thus to contribute to the knowledge of the health status of the individuals that inhabit the bay. Blood films were analyzed in search of haemoparasites and hematocrit and 17 variables of blood biochemistry were measured. The individuals sampled correspond mostly to adult females (n= 5) and juveniles of undetermined gender (n= 2). All of the individuals were classified as healthy after the clinical examination performed by the veterinarian in charge. Blood samples were obtained from the external jugular vein immediately after the capture, reducing stress. Samples were prepared and stored in the field, and transported for analysis to the Laboratory of Hematology and Clinical Biochemistry at the Faculty of Veterinary Sciences and Animal Husbandry at the University of Chile. Mean, standard deviation, medium and minimum and maximum values for each variable were obtained considering the samples as a whole without considering confidence intervals due to the low n. The packed cell volume and plasma total protein were found to be within the reference values used for C. mydas in other parts of the world. The narrow ranges obtained for total protein, albumin, globulins, glucose, uric acid, calcium, phosphorus and total bilirubin may be due to the low number of samples. Blood film analysis determined no presence of hemoparasites. The low number of samples used in the present study did not allow making statistically significant comparisons so we must continue studying the area in order to capture more animals that improve the total number to obtain reference ranges for the colony to be statistically significant. Taking into account all the hematological results,
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coupled with the clinical external examination of the turtles of Bahía Salado, it is possible to suggest that this is a healthy colony. In conclusion, the hematologic and blood biochemical features found in the present study would be a feature of this colony due to the habitat, food availability (type and abundance) and to the sex and age structure of the individuals that conform this colony.<br>Financiamiento: Proyecto DPA14LIHBCA1415100 y O.N.G Querapara Tortugas Marinas Chile.
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Dantas, George Alexandre Ferreira. "Linhas convulsas e tortuosas retificações: transformações urbanas em Natal nos anos 1920." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18131/tde-10072008-171540/.
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Esta dissertação discute o processo de transformações urbanas por que a cidade de Natal-RN passou na década de 1920, período decisivo para a conformação de sua estrutura e paisagem modernas. Procurando compreender o contexto político, cultural e social que suscitou o plano geral de sistematização, elaborado pelo arquiteto Giacomo Palumbo entre 1929 e 1930, aborda-se: o processo mais longo de modernização urbana empreendido desde o final do século XIX, apontando a ascensão do olhar técnico, em especial o médico, sobre o espaço urbano; as representações de \"crise\" urbana que se instauraram em Natal no início dos anos 1920; as narrativas literárias e historiográficas que revelam o esforço pela compreensão dos significados das mudanças que se processavam e, tarefa na qual o papel do intelectual Câmara Cascudo foi fundamental, pela construção da história da cidade; a relação entre saneamento e educação que secundaram as discussões sobre o plano elaborado pelo engenheiro Henrique de Novaes para Natal, em 1924; a administração municipal do engenheiro Omar O\'Grady (1924- 1930) e seu esforço pela racionalização e eficiência das reformas urbanas; o lugar e as influências do plano de Palumbo no contexto da cultura urbanística moderna gestada no início do século XX; e, por fim, acompanha-se a passagem do \"turista aprendiz\" Mário de Andrade por Natal entre 1928 e 1929 e a representação de cidade que emerge dos seus relatos, a partir das errâncias pelo espaço tradicional - uma cidade distante das representações apologéticas e oficiais.<br>This dissertation aims to discuss the process of urban transformations by which the city of Natal has passed in the 1920s. This period was fundamental to conform Natal\'s modern urban structure and landscape. By intending to comprehend the social, cultural, and political context that foments the master plan, elaborated by architect Giacomo Palumbo between 1929 and 1930, it discusses: the urban modernization process that had been developed since last decades of XIXth century, pointing specifically the emerging of a technical approach on urban space; the representations of urban \"crise\" which marked the history of Natal in the beginnings of 1920s; the literary and historiographical narratives that reveal the efforts for comprehending the meanings of urban transformations and for constructing a history of the city, task in which the intelectual Câmara Cascudo was fundamental; the relations between sanitation and education into the urban plan elaborated by engineer Henrique de Novaes in 1924; the municipal administration of engineer Omar O\'Grady (1924-1930) and his efforts to racionalizate and to get efficiency in the urban reforms; the influences and characteristics of Palumbo\'s master plan related to the culture of town planning developed since the beginnings of XXth century. Finally, it discusses the accounts on Natal produced by the intelectual Mario de Andrade in the end of 1920s.
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Roche, David C. "Trophic Ecology of Green Turtles (Chelonia mydas) From Dry Tortugas National Park, Florida." NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/430.
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Located 100 km west of Key West, Florida, Dry Tortugas National Park (DRTO) is a largely untouched subtropical marine ecosystem that serves as an important developmental habitat, nesting ground, and foraging area for several species of sea turtles, including green turtles. The Park supports a recovering population of green turtles comprised of resident juveniles, subadults, and adults of both sexes; nesting females include residents and migrating females that only return to nest. Stable isotope analysis has been applied widely to describe the trophic ecology of green turtles, from urbanized bays with significant anthropogenic input, to relatively pristine ecosystems with healthy populations at carrying capacity. However, there is a paucity of published literature about the trophic ecology of green turtles in DRTO. This study describes the trophic ecology occupied by two distinct size groups (61 green turtles < 60 cm (SCL) and 98 green turtles > 60 cm (SCL)). Flipper tissue and plasma were analyzed for stable isotopic composition of C and N. Flipper tissue values for δ15N (3.41‰ to 9.69‰) and δ13C (-22.43‰ to -5.38‰) fall within literature values for green turtles, and the wide range of values indicated they could potentially feed at multiple trophic levels. Understanding the trophic ecology of this population of green sea turtles is instrumental to effective management and habitat preservation strategies in DRTO.
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Meyer, Léon. "Diversité parasitaire au sein de tortues d’eau douce indigènes et invasives : implications aux problèmes de conservation." Perpignan, 2014. http://www.theses.fr/2014PERP1256.
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Les tortues forment l'un des groupes de vertébrés les plus menacés au monde avec à peu près la moitié des 300 espèces existantes en danger d'extinction, en particulier suite aux invasions biologiques. Cette thèse a été réalisée pour évaluer la part des transferts de parasites de la trachémyde à tempes rouges, Trachemys scripta elegans espèce de tortue d’eau douce américaine invasive, vers les tortues d’eau douce dans leurs environnements naturels et leur impact sur la biodiversité. A partir d’analyses du type « DNA barcoding » basées sur le séquençage de la Cytochrome c Oxydase I (COI) d’échantillons parasites collectés sur l’émyde lépreuse (Mauremys leprosa), espèce indigène du sud de l’Europe, l’arbre de « Mimimum Evolution » ainsi que la comparaison des distances p calculées entre les haplotypes les plus proches dans l’arbre ont révélé une richesse spécifique chez cette espèce beaucoup plus grande que celle attendue, suggérant ainsi de nombreux transferts d’hôtes en milieu naturel. Les résultats indiquent également que T. S. Elegans servirait de vecteur pour une variété de polystomes d’origine américaine, qui seraient alors transmis à l’espèce hôte indigène. Cette thèse comprend également trois autres études, la première est consacrée à l’évaluation des risques, développée à partir de l’approche « Relative Risk Model » pour estimer la viabilité de M. Leprosa dans une petite rivière du sud de la France, la seconde à la diversité des hémogrégarines (Apicomplexa, Haemogregarinidae) des tortues d’eau douce d'Afrique du Sud et la troisième à la relation entre production d'œufs de parasites et les conditions environnementales<br>Terrapins are one of the most endangered vertebrate groups of the world, with almost half of the more than 300 extant species threatened with extinction, particularly following biological invasions. This study was conducted to investigate parasite host-switching from the invasive American Red-eared slider, Trachemys scripta elegans, to native freshwater turtles in natural environments, and their impact to biodiversity. From DNA barcoding analysis based on the sequencing of the Cytochrome c Oxidase I gene (COI) of parasites collected from the Mediterranean pond terrapin (Mauremys leprosa) in Southern Europe, the inferred Minimum Evolution tree and p-distance comparisons of closely related haplotypes revealed a greater polystome richness within M. Leprosa than expected, suggesting that host switching may take place in natural environments. Results also indicate that T. S. Elegans would serve as a carrier for a variety of polystomes that usually infest American turtles in their home range. These parasites would be transmitted to M. Leprosa in its home range. The thesis also includes three other studies, the first one involves a risk assessment approach that was developed using the Relative Risk Model (RRM) method to assess the viability of the native M. Leprosa terrapin in a small river of southern France, the second one examines the diversity of terrapin haemogregarines (Protozoa: Apicomplexa: Haemogregarinidae) in South Africa and the fourth one investigates polystome egg production under changing environmental conditions
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Plot, Virginie. "Caractéristiques maternelles, performances et stratégies de reproduction des tortues marines de Guyane." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00867096.
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Les organismes font face à des compromis entre leur reproduction, leur maintenance et leur survie, dont découlent des stratégies adaptatives énergétiques, comportementales et écologiques.Ce travail de thèse propose de préciser les stratégies de reproduction chez la tortue luth Dermochelys coriacea nidifiant en Guyane. Nous avons étudié les caractéristiques maternelles, les performances de reproduction et les potentiels liens existants entre la migration et la reproduction chez une population d'individus d'identité connue, suivis grâce à un suivi longitudinal original combinant biométrie, physiologie et biologie moléculaire.Premièrement nous montrons que les tortues luth opèrent comme des reproducteurs sur capital, i.e., leur reproduction repose sur les ressources stockées sous forme de réserves corporelles pendant la migration précédant la saison de ponte. D'autre part, nous suggérons que les femelles ajustent la durée de leur migration en fonction des conditions océanographiques rencontrées pendant la migration. Ceci leur permettrait, à l'échelle de la vie, de répondre au compromis entre la reproduction en cours et les reproductions futures. Enfin, notre démarche souligne l'importance de prendre en compte les caractéristiques individuelles dans la compréhension des stratégies de reproduction, et de manière ultime pour l'établissement de modèles réalistes de la dynamique des populations, notamment dans le cas d'espèces emblématiques telles que les tortues marines.
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Bole, Cyprien. "Etude ostéo-morphométrique des tortues marines de la super-famille des Chelonioidea." Paris, Muséum national d'histoire naturelle, 2010. http://www.theses.fr/2010MNHN0021.
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La taxonomie de la super-famille des Chelonioidea (toutes les tortues marines actuelles, excepté la tortue luth) a beaucoup fluctué depuis sa création en 1811 par Oppel. Si de nombreuses études ont été réalisées, concernant d’une part la description de caractères qualitatifs et quantitatifs permettant de distinguer les espèces, et d’autre part le génome, aucune n’a été véritablement menée dans l’optique de quantifier les conformations géométriques du squelette et d’exposer leurs particularités. Les crânes, les mandibules et cinq os longs de 307 spécimens des collections du Chelonian Research Institute (USA) ont été numérisés à l’aide de trois méthodologies différentes de morphométrie géométrique : positionnement de points repères 2D, positionnement de points repères 3D et relevés de contours 3D. Pour tous les spécimens, nous connaissions l’espèce, le stade de développement, la provenance et le sexe. Ainsi, nous avons pu étudier la variabilité liée à ces quatre facteurs au sein de ces structures osseuses. La morphométrie géométrique permet de faire la synthèse, à l’échelle de précision souhaitée, de la géométrie d’un objet dans sa globalité. Elle bénéficie d’un fondement mathématique rigoureux qui garantit des statistiques robustes. Plusieurs champs d’analyses ont été développés et tout particulièrement au sein du genre Chelonia où nous avons estimé, comparé et visualisé la variabilité des individus de l’Atlantique ouest, de la région Indo-Pacifique et du Pacifique aux différents stades de développement. Ces populations présentent en effet des différences importantes au niveau de la géométrie de leur squelette pouvant expliquer en partie la fluctuation de la taxonomie du genre Chelonia et la discussion du paraphylétisme de Chelonia mydas. La géométrie de tous les os étudiés est différemment corrélée avec les facteurs retenus, excepté le sexe pour lequel la variabilité des conformations semble moins structurée. Ceci permet d’envisager de nombreuses applications pratiques : amélioration des connaissances générales de la biologie de ces reptiles (le suivi satellite étant très coûteux en raison des fortes mortalités naturelles et autres), mais aussi détermination de spécimens, voire de restes archéologiques de tortues marines qui aujourd’hui ne sont pas étudiés, bien qu’il soit fréquent d’en retrouver sur des sites littoraux de nombreuses régions du monde<br>The taxonomy of the super-family Chelonioidea (all the extant marine turtles except the leatherback) has changed many times since its creation in 1811 by Oppel. Today numerous studies have been carried out both on the descriptive characters (qualitative and quantitative) for distinguishing species and about their genomes. But none has really been devoted to quantifying the bone’s geometrical shape and conformations that should better their knowledge. The skulls, lower jaws and five long bones of 307 specimens belonging to the Chelonian Research Institute (USA) were digitized using three different geometric morphometrics methods: 2D landmarks, 3D landmarks, 3D outlines. For each specimen, we had information about the species, stage of development, origin and sex. We studied the shape variability related to these four factors in the bony structures. Geometric morphometrics allow to synthesis the global geometry of an object. It has a rigorous mathematical background and ensures robust statistics. We tested several hypotheses, especially among the genus Chelonia where we compared and visualized the shape variability of western Atlantic, Indo-Pacific and Pacific individuals, including the three stages of development. As these populations presented significant differences in the bony structure geometry, thus may partly explain the fluctuation of the taxonomy of the genus Chelonia and the discussion of the paraphyletism of the current species Chelonia mydas. The geometry of all the bones we studied was correlated with the different factors we tested, except for the sex for which the shape variability seems to be less structured. This allows to consider several practical applications: to improve the general knowledge of the biology of these reptiles (as satellite tracking is very expensive because of the high natural level of mortality), but also to make determinations of specimens or of archaeological sea turtles remains, which are fairly frequent
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Peron, Christina. "Dynamique littorale et comportement de ponte des tortues marines en Guyane française." Thesis, Littoral, 2014. http://www.theses.fr/2014DUNK0369/document.
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Le littoral guyanais accueille chaque année les pontes de tortues marines. En Guyane, les tortues doivent faire face à l’instabilité côtière liée au passage d’imposants bancs de vase le long du littoral. Dans ce contexte, les plages de ponte peuvent devenir non attractives si elles présentent une érosion trop marquée ou si elles sont envasées. L’instabilité de ce littoral peut également induire la création de nouveaux sites sableux (cheniers), sites de ponte potentiels.Ce travail de thèse s’attache à étudier la dynamique morphosédimentaire des plages sableuses servant d’habitat de ponte aux tortues et les répercussions de la migration des bancs sur ces plages. La principale zone d’étude, la plage d’Awala-Yalimapo, a été instrumentée entre 2011 et 2013, et a permis de comprendre le fonctionnement hydro-sédimentaire d’une des principales plages de ponte guyanaises à une échelle mensuelle à pluriannuelle. Parallèlement à ce travail, l’activité de ponte des tortues marines a été recensée permettant de mettre en évidence l’utilisation de certains paramètres environnementaux dans la sélection finale du site de ponte. Les principaux déterminants sont la configuration de l’avant-plage, la hauteur d’eau, les courants de marée et la dynamique morphosédimentaire de la plage d’accueil<br>French Guiana coast host, each year, marines turtles nesting. In French Guiana, marine turtles managed with the extreme coastal variability due to the migration of huge mud bank. In this context, nesting beaches could be unattractive if erosion is too intense or if there are silted-up. The instability of this coast could induce the creation of new sandy coastline (cheniers) and so on potential nesting site.The aim of this PhD work was to study the morphodynamics of sandy beaches which are also nesting site for marine turtles and the consequence of mud bank migration on these beaches. In-situ measurements were carried-out on the principal study area, Awala-Yalimapo beach, and permitted to increase our knowledge on the hydro-sedimentary evolution of one of the primary nesting site from daily to multiannual time scale. In the same time, the nesting activity of marine turtles was listed to highlight the use of environmental parameters in the finale selection of the nesting site. Principal environmental clues were the beach configuration, the water level, tidal current and the morphodynamics of the nesting habitat
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Franch, Quintana Marc. "Problemàtica i conservació de tortugues aquàtiques continentals a l'Europa occidental: el cas de la tortuga de rierol, Mauremys leprosa (Schweigger 1812), al nord-est de la Península Ibèrica." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/402608.
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La tortuga de rierol (Mauremys leprosa) és una espècie de tortuga aquàtica continental que es distribueix pel nord d’Àfrica, la Península Ibèrica i una petita part del sud de França. Aquesta distribució coincideix amb una de les zones amb major quantitat d’impactes d’origen antròpic de la Conca Mediterrània. L’espècie està considerada actualment com a ‘Vulnerable’ a nivell de l’Estat Español i ‘En Perill’ a França a causa de l’alteració, la fragmentació i pèrdua d’hàbitat, la presència d’individus o poblacions de tortugues exòtiques invasores i la translocació d’individus al·lòctons entre d’altres.
Amb aquesta tesi es pretén analitzar aquestes problemàtiques des d’una òptica de conservació de l’espècie i té com a objectiu de determinar els efectes dels impactes antròpics sobre les poblacions de Mauremys leprosa al límit de la seva àrea de distribució i aportar coneixement, recursos i eines per a poder-hi fer front. Per assolir aquest objectiu s’ha actualitzat la seva corologia i modelitzat la distribució potencial de M. leprosa a Catalunya en diferents períodes de temps per determinar els requeriments bioclimàtics generals i possibles canvis al llarg del temps, se n’han descrit les tendències geogràfiques i temporals a Catalunya i les seves estructures poblacionals al límit nord de la seva distribució. S’ha determinat a més, la diversitat genètica i el possible origen de les seves poblacions. A nivell local, s’ha descrit i avaluat l’estat de les poblacions de M. leprosa i de Trachemys scripta elegans al Delta del Llobregat, se n’han caracteritzat també la biologia bàsica i les possibles interaccions interespecífiques a partir de anàlisi de nínxol ambiental i de paisatge.
Amb els resultats obtinguts, s’ha determinat que M. leprosa és una espècie cada cop més comú i que sembla gaudir d’un relatiu bon estat de conservació al nord-est de la Península Ibèrica i al sud de França. En general presenta una bona situació demogràfica arreu de la zona d’estudi amb algunes excepcions puntuals. Així, l’espècie es defineix com a termòfila i generalista d’hàbitat i relativament tolerant a l’alteració d’aquest, tant a escala de estructura de paisatge com a la dels ambients aquàtics on resideix.
T. s elegans al Delta del Llobregat presenta una població poc estructurada però amb una elevada capacitat invasora. En l’anàlisi de la interacció espacial entre la tortuga de rierol i la de tempes roges s’ha detectat un baix solapament de nínxol basat en característiques dels ambients aquàtics i el paisatge circumdant però e fet que M. leprosa es trobi en ambients amb elevada salinitat, baixa eutrofització i més deteriorats suggereix que aquesta es troba altament condicionada per la presència de T. s. elegans. Els resultats obtinguts en l’anàlisi genètica de les diferents poblacions de M. leprosa estudiades han determinat la continuïtat geogràfica de les poblacions catalanes i les del sud de França i s’ha constatat la translocació i la lliure circulació d’individus de M. leprosa.
Per poder fer front a aquestes amenaces que afecten a M. leprosa, cal emprendre una sèrie d’accions a nivell de coneixement de l’espècie, de conservació d’aquesta i dels hàbitats i a nivell de ciutadania per tal de garantir la preservació de la tortuga de rierol i la biodiversitat que l’acompanya.<br>The Mediterranean stripe-necked terrapin (Mauremys leprosa) is a freshwater turtle and its distribution is restricted to northwestern Africa, Iberian Peninsula and a small part of southern France. This distribution coincides with one of the areas with the most anthropogenic impacts in the Mediterranean Basin. The species is considered as 'Vulnerable' in Spain and 'Endangered' in France due to degradation, fragmentation and habitat loss, the presence of individuals or populations of exotic invasive turtles species and intraspecific translocations among others.
This thesis aims to analyze these problems from a conservation of the species perspective and to determine the effects of anthropogenic impacts on the Mauremys leprosa populations of the limit of its range and provide knowledge resources and tools to be able to deal these problems. To achieve this goal was updated its chorology and modelled the potential distribution of M. leprosa in Catalonia in different time periods to determine the general bioclimatic requirements and possible changes over time, was described temporal and geographic trends in Catalonia and was described populational structures at the north of the range. Also, we was determined the genetic diversity and the possible origin and of their populations. Locally, we described and evaluated the freshwater turtles populations status (M. leprosa and Trachemys scripta elegans) in the Llobregat Delta and was characterized the basic biology and interspecific interactions between them with environmental and landscape niche analysis.
With the results, we was determined that a species is M. leprosa increasingly common and seems to enjoy a relatively good state of conservation in the northeast of the Iberian Peninsula and southern France. In general presents a good demographic situation across the study area with some occasional exceptions. Thus, the species is defined as thermophilic and habitat generalist with relatively habitat alteration tolerance at landscape structure and aquatic environments scales.
T. s. elegans has an unstructured population in the Llobregat Delta with high invasiveness degree. The analysis of spatial interaction shows low niche overtlap between native M. leprosa and the invasive T. s. elegans but the presence of M. leprosa in high salinity, low eutrophication and damaged environments suggests that this species is strongly conditioned to the presence of the invasive T. s. elegans. The results of the genetic analysis of the different M. leprosa populations studied was determined the geographic continuum of the Catalan and southern France populations and intraspecific translocations was reported.
With the aims to cope with these threats that affects M. leprosa, must perform actions at the knowledge of the species level, species and habitats conservation and citizenship level in order to guarantee the species and accompanying biodiversity conservation.
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Muro, Figueres Jesús. "Estudio sanitario de las tortugas terrestres mediterráneas (Género Testudo) e implicaciones para su conservación." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/377460.
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Las tortugas terrestres mediterráneas, tortuga mediterránea (Testudo hermanni) y tortuga mora (Testudo graeca), presentan problemáticas similares de conservación en España, si bien, la primera está más amenazada. Los programas de conservación, tanto in-situ como ex-situ, deben incluir una adecuada gestión sanitaria. Uno de los aspectos básicos es el establecimiento de los parámetros sanguíneos de referencia para la adecuada interpretación y evaluación del estado sanitario de cada especie. En el primer estudio, realizado en tortuga mediterránea occidental (T. h. hermanni), se valoró el efecto de dos anticoagulantes, heparina de litio y EDTA tripotásico, sobre los parámetros hematológicos. La heparina de litio fue el anticoagulante de elección para las muestras sanguíneas en estos quelonios.
Los procesos infecciosos pueden comprometer la viabilidad de las poblaciones de tortugas y son un importante factor a tener en cuenta para la gestión de los centros de cría en cautividad y para la liberación de animales. En el segundo estudio se describe un brote de rinitis crónica asociada a un herpesvirus en una población cautiva de tortuga mora. Los signos clínicos más relevantes fueron rinitis seromucosa bilateral, estomatitis y glositis. Se realizó un estudio hematológico y bioquímico sanguíneo y se comparó con los datos obtenidos en animales sanos de tres poblaciones diferentes. Los animales enfermos mostraron heteropenia, linfocitosis, incremento en la actividad de la AST y aumento de la concentración de α-globulina. Algunos de ellos tenían anemia normocítica y normocrómica. Las lesiones se circunscribían al aparato respiratorio y a la cavidad oral, con marcada hiperplasia epitelial y presencia de infiltrado mixto inflamatorio en el epitelio de la mucosa oral, nasal y traqueal. La microscopía electrónica evidenció la presencia de partículas virales intracitoplasmáticas e intranucleares que, por su tamaño, forma y patrón de distribución, se correspondían con un herpesvirus.
La cría en cautividad de especies en peligro de extinción supone unos riesgos sanitarios que las poblaciones salvajes no tienen. En el tercer estudio se describe un episodio de micobacteriosis sistémica atípica en tortuga mediterránea occidental en una población cautiva. Los síntomas aparecieron al final del período de hibernación, en forma de anorexia, embotamiento y letargia, junto a lesiones inflamatorias y edematosas en las extremidades y cola. Los animales afectados fueron eutanasiados. La mayoría de tortugas presentaron una marcada leucocitosis y anemia. Se observó un incremento de AST, ALT, LDH y FA, disminución de los ácidos biliares e hiperproteinemia, con aumento de la fracción globulina y disminución de la fracción albúmina y del cociente A/G en dos animales. En los aspirados articulares se observaron numerosas células mononucleares con abundantes estructuras bacilares fagocitadas. Mediante una tinción de Ziehl-Neelsen se evidenció la presencia de estructuras bacterianas ácido-alcohol resistente. Las lesiones se localizaron en ovario, páncreas, pulmón, bazo, corazón, musculatura caudal, riñón e hígado. El cultivo e identificación para micobacterias fue positivo, así como la secuenciación molecular, mediante la que se identificó Mycobacterium nonchromogenicum.
Los aspectos sanitarios en los reptiles están insuficientemente estudiados y valorados para la cría en cautividad y la conservación de las especies amenazadas. En este estudio se comprueba como la heparina de litio es el anticoagulante de elección para la toma de muestras sanguíneas en tortugas terrestres mediterráneas y como las infecciones por herpesvirus y micobacterias pueden comprometer la conservación ex-situ de estas especies.<br>Mediterranean tortoises, Hermann’s tortoise (Testudo hermanni) and spur-thighed tortoise (Testudo graeca) have similar conservation issues in Spain, although the first has disappeared from most of its original habitat and is more threatened. Both in-situ and ex-situ conservation programs should include adequate health management. One of the main aspects is the establishment of reference values for blood parameters for the proper interpretation and evaluation of the health status of each species. In the first study, conducted in the western Mediterranean tortoise (T. h. hermanni), the effect of two types of anticoagulants, heparin lithium and EDTA tripotassium, on hematological parameters was evaluated. Heparin lithium is considered as the anticoagulant of choice for blood samples of these chelonians.
Infectious diseases can compromise the viability of tortoise populations and are important factors to consider in the management of captive populations and for the release of animals, to reinforce wild populations. In the second study, an outbreak of chronic rhinitis associated with a herpesvirus in a captive population of spur-thighed tortoise is described. The most relevant clinical findings were bilateral effusion rhinitis, accompanied by stomatitis and glossitis. An hematological and serum biochemical study was performed and compared with data from healthy animals from three different populations. Diseased animals showed heteropenia, lymphocytosis, increased AST activity and higher α-globulin concentration. Some tortoises showed normocytic and normochromic anemia. The lesions were confined to the respiratory tract and the oral cavity, with marked epithelial hyperplasia and presence of mixed inflammatory infiltrate in the epithelium of the oral, nasal and tracheal mucosa. Electron microscopy revealed the presence of intracytoplasmic and intranuclear viral particles whose size, shape and distribution pattern corresponded to a herpesvirus.
Captive breeding of endangered species are more subjected to health risks that wild populations. In the third study, an episode of systemic atypical mycobacteriosis in a captive population of Western Hermann’s tortoise is described. The symptoms appeared at the end of the period of hibernation, in the form of anorexia, dullness and lethargy, with inflammatory and edematous lesions on the limbs and tail. Blood samples, joint taps and skin biopsies were performed. Lately, euthanasia of affected animals was performed. Most tortoises showed marked leukocytosis, with heteropenia, monocytosis and a large number of mononuclear cells, and five animals had anemia. An increase in the values of AST, ALT, LDH and FA, a decrease in bile acids and hyperproteinemia with increased globulin and decreased albumin and A/G ratio were observed. In joint taps, mononuclear cells with phagocytosed bacillary structures were obseved. Ziehl-Neelsen stain revealed the presence of acid-fast bacteria. Lesions were observed in ovaries, pancreas, lungs, spleen, heart, muscle, kidney and liver. Culture and identification were positive for mycobacteria and molecular sequencing lead to the identification of Mycobacterium nonchromogenicum.
Health aspects in reptiles are insufficiently studied and assessed for captive breeding and conservation of threatened species. In this study, it was found that lithium heparin is the anticoagulant of choice for blood sampling in Mediterranean tortoises and infections such as those cause by herpesvirus and mycobacteria may compromise the ex-situ conservation of these species.
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Waara, Robert J. "Development and Policy Applications of the 2010 Benthic Habitat Map for Dry Tortugas National Park." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_theses/247.
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In 2008 an initial benthic habitat map was completed by the contractor Avineon, Inc. The National Park Service South Florida / Caribbean Network (SFCN) conducted an accuracy assessment of the map and found the overall habitat identification to be acceptable. However, upon further inspection, the soft-bottom habitat classifications displayed a relatively high level of accuracy, while the hard-bottom habitats were below an acceptable level. With the acquisition of new higher resolution side scan sonar data and 2054 field data points from multiple sources, the 2008 map was revised and improved by utilizing these new data sets to produce the 2010 Dry Tortugas benthic habitat map. The 2010 Dry Tortugas benthic habitat map was developed using 13 mapping classes and 1709 polygons totaling an area of 26,229 hectares. All “Unknown” areas (10,444 hectares) in the 2008 map were identified, the line work for the hard-bottom areas was fine-tuned and a mapping layer was developed showing those areas which have a higher potential for fish and benthic biodiversity. In addition, a final bathymetry layer for the park was developed by merging the existing light detection and ranging (LiDAR) and newly acquired side scan sonar/bathymetry data. The current management plan for the Dry Tortugas National Park (DRTO) marine areas focuses much of its effort on the Research Natural Area (RNA). The intensive amount of research effort placed on the RNA has also accomplished the research needed for the rest of DRTO because current research and monitoring efforts are split equally between areas of the DRTO that fall within and outside the RNA to make for a balanced comparative study design. In February of 2007, National Park Service (NPS) and Florida Fish and Wildlife Conservation Commission (FWC) developed a science plan to assess conservation effectiveness for the RNA in conjunction with the rest of DRTO and the two nearby existing marine reserves. The implementation of the science plan has been accomplished through collaboration and cooperation of federal and state agencies, academic scientists, and NPS. The new benthic habitat map and corresponding products will help in showing what types of marine habitats are located in the Dry Tortugas National Park and provide the ability to track whether management interventions are effectively protecting the environment and associated resources.
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Alchaar, Maria Mayrenne de Freitas. "Perfil químico das flores de Erythroxylum e caracterização química das folhas de E. Tortuosum (Erythroxylaceae)." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/8923.
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Previous issue date: 2018-04-19<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>The Cerrado is known as the world’s richest savanna in biodiversity, but still little explored from the chemical view. Among the genus of plants found in this biome, there is Erythroxylum (Erythroxylaceae), which is known mostly for the tropane alkaloids metabolites. This work describes a comparative study of flowers chemical profile from E. campestre, E. suberosum e E. tortuosum, as well as the chemical study of E. tortuosum leaves. To obtain the chemical profile of flowers for the different species, the extracts were prepared in hexane, dichloromethane, ethyl acetate and methanol, which were analyzed by 1H NMR, HPLC UV/DAD and GC-MS. The data showed similar phytochemical composition in the species investigated, suggesting attendance of terpenes, flavonoids and alkaloids. The GC-MS analysis afforded to identify hydrocarbons, aldehydes and a phenolic derivative. The extracts of the leaves of E. tortuosum were prepared likewise the flowers extracts, but to obtain alkaloids it was performed an acid-base extraction of the methanolic extract of the leaves. From the ethyl acetate and methanolic extracts of leaves, were identified six substances: α-amyrin (I), β-amyrin (II), campesterol (III), stigmastan-3,5-diene (IV), β-sitosterol (V) and 7,4’-di-O-methylquercetin-3-O-β -rutinoside (IX), which flavonoid was found as the major compound of extracts. Through the alkaloid extraction it was possible to identify three tropane alkaloids: tropacocaine (VI), cocaine (VII) and 6-methoxy-8-methyl-8-azabicyclo[3.2.1]octan-3-ol (VIII), and among them, compound (VIII) was described for the first time in Erythroxylum genus. The results obtained are important for the chemical knowledge of the Cerrado biodiversity, since there are not much data in the literature about the species studied in this work.<br>O Cerrado é reconhecido como a savana mais rica do mundo em biodiversidade, porém pouco explorado do ponto de vista químico. Dentre os gêneros de plantas existentes neste bioma, encontra-se Erythroxylum (família Erythroxylaceae) que é conhecido principalmente pela produção de alcaloides tropânicos. Este trabalho descreve o estudo comparativo do perfil químico das flores das espécies E. campestre, E. suberosum e E. tortuosum, assim como o estudo químico das folhas de E. tortuosum. Para o perfil químico das flores foram obtidos extratos em hexano, diclorometano, acetato de etila e metanol, que foram analisados por RMN 1H, CLAE UV/DAD e CG-EM. Os dados mostraram semelhança de perfil químico entre as espécies estudadas, sugerindo a presença de terpenos, flavonoides e alcaloides. A partir das análises por CG-EM foi possível identificar hidrocarbonetos, aldeídos e um derivado fenólico. Os extratos das folhas de E. tortuosum foram preparados de modo semelhante ao procedimento utilizado para as flores, além de realizar extração ácido-base no extrato metanólico para obtenção de alcaloides. Dos extratos acetato de etila e metanólico das folhas foram identificadas seis substâncias: α-amirina (I), β-amirina (II), campesterol (III), estigmastan-3,5-dieno (IV), β-sitosterol (V) e 4’,7-di-O-metilquercetina-3-O-β-rutinosídeo (IX), sendo o flavonoide o composto majoritário dos extratos. Através da extração alcaloídica foi possível identificar três alcaloides tropânicos: tropacocaína (VI), cocaína (VII) e 6-metoxi-8-metil-8-azabiciclo[3.2.1]octan-3-ol (VIII), sendo o último relatado pela primeira vez no gênero Erythroxylum. Os resultados obtidos contribuem para o conhecimento químico da biodiversidade do Cerrado devido à escassez de estudos relacionados à constituição química das espécies estudadas.
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Batalla, Lozano Luis Alberto. "Presencia de hemoparásitos en “tortugas motelo” (Geochelone denticulata) (Linnaeus, 1766) comercializadas en el mercado de Belén, Iquitos." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2013. https://hdl.handle.net/20.500.12672/9657.
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Publicación a texto completo no autorizada por el autor<br>Identifica y determina la presencia de hemoparásitos en tortugas motelos comercializadas en el mercado de Belén en Iquitos. Así como, su asociación con las variables; sexo, peso, hematocrito, parasitemia. Se colectaron muestras de sangre de 47 tortugas beneficiadas en el mercado de Belén en Iquitos, durante el mes de julio del 2010. Las muestras fueron analizadas en el Laboratorio del Centro Experimental IVITA – Iquitos y en el Laboratorio de Microbiología y Parasitología, sección de Parasitología de la Facultad de Medciina Veterinaria de la Universidad Nacional Mayor de San Marcos (FMV-UNMSM), para la identificación de hemoparásitos se utilizó la técnica de frotis sanguíneo delgado con Giemsa, microcapilar de Woo y técnica de capa blanca o Buffy coat. Los resultados de la evaluación hematológica mostraron la presencia de Haemogregarina sp. con una frecuencia de 74.5% en tortugas motelo. Las frecuencias de las variables sexo para hembras y machos fueron 68.8% y 86.7% respectivamente. Se encontraron dos formas de gamontes: maduros e inmaduros siendo sus medidas 11.09 ± 1.42µm x 5.8 ± 0.83µm y 14.84 ± 0.68µm x 3.22 ± 0.41µm respectivamente. No se encontró diferencia significativa (p>0.05) entre las variables sexo, peso, hematocrito y parasitemia.<br>Tesis
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Belaiba, Meriam. "Identification d'extraits bioactifs obtenus à partir de trois plantes médicinales tunisiennes : Ammoides pusilla (Apiaceae), Pituranthos tortuosus (Apiaceae) et Tetraclinis articulata (Cupressaceae)." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30345.
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Dans cette thèse, on a travaillé sur 3 plantes médicinales : Ammoides pusilla, Pituranthos tortuosus et Tetraclinis articulata. L'objectif était : (i) d'identifier la composition chimique des extraits organiques et des huiles essentielles issues de ces plantes, (ii) établir un screening biologiques in vitro des activité anti-Alzheimer, anti-Superoxyde dismutase, anti-xanthine oxidase, antidiabétique, anti-inflammatoire et anti-cancer (iii) évaluer in vivo le pouvoir hépatoprotecteur et anti-inflammatoire de A. pusilla, (iv) étudier l'activité litholytique de l'extrait aqueux d'A. pusilla contre différents types de calculs rénaux et (v) déterminer la relation structure-activités de 20 flavonoïdes. Les extraits organiques ont été obtenus par extraction avec des solvants de polarité croissante. D'autre part, une hydrodistillation a permis d'extraire les huiles essentielles de chaque partie aérienne. Une caractérisation de la composition chimique de ces extraits/huiles essentielles a été établie par CPG-SM/CG-FID et HPLC (pour les extraits). L'activité anti-cancer a été réalisée par le test MTT sur des lignées cellulaires différentes. Pour A. pusilla, 2 nouveaux composés ont été identifiés dans l'extrait de cyclohexane et 4 nouveaux composés dans l'extrait de dichlorométhane. L'effet hépato protecteur de l'extrait d'A. pusilla sur le foie a été mis en évidence. L'extrait de dichlorométhane a permis d'obtenir 77,02% d'inhibition, pour l'activité anti-inflammatoire in vivo. Pour P. tortuosus, 17 composés ont été détectés dans l'huile essentielle pour la première fois. Pour les 20 flavonoïdes testés le pouvoir antioxydant a été corrélé à des propriétés biologiques. Cinq types de calculs rénaux différents ont été identifiés (typologie et composition élémentaire) par MEB/EDX. A. pusilla a présenté une activité litholytique à 100% pour les calculs rénaux de type urinaire et oxalate de calcium<br>In this thesis, we worked on 3 medicinal plants: Ammoides pusilla, Pituranthos tortuosus and Tetraclinis articulata. The aim was: (i) identify the chemical composition of organic extracts and essential oils from these plants, (ii) establish a biological screening of in vitro anti-Alzheimer, anti-superoxide dismutase, anti-xanthine oxidase , anti-diabetic, anti-inflammatory and anti-cancer activities (iii) evaluate in vivo hepatoprotective and anti-inflammatory power of A. pusilla, (iv) study litholytic activity of aqueous extract of A. pusilla against different types of kidney stones and (v) determine the relationship structure-activity of 20 flavonoids. The organic extracts were obtained by extraction with solvents of increasing polarity. Furthermore, a hydrodistillation was used to extract essential oils from each aerial part. A characterization of the chemical composition of these extracts / essential oils was determined by GC-MS/GC-FID and HPLC (for extracts). The anti-cancer activity was carried out by MTT assay on different cell lines. For A. pusilla, two novel compounds were identified in the extract of cyclohexane and 4 novel compounds in the dichloromethane extract. A. pusilla hepatoprotective effect on the liver has been highlighted. The dichloromethane extract of P. tortuosus gives 77.02% inhibition for in vivo anti-inflammatory activity, 17 compounds were detected in the essential oil for the first time. For the 20 flavonoids tested the antioxidant power was correlated with biological properties. Five different types of kidney stones have been identified (typology and elemental composition) using SEM / EDX. A. pusilla litholytic activity presented at 100% for urinary-type and calcium oxalate kidney stones
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Barbanti, Anna. "Sea turtle conservation: genetics and genomics for a better management." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/672159.
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Conservation actions aim to preserve and recover animal and plant species using in-situ or ex- situ strategies. The first, aims to protect and sustain populations in their natural habitat, the second are implemented when local populations are extinct or are about to be. Conservation genetics can provide important insights into the dynamics of endangered populations facilitating their management.
This thesis uses traditional markers and new generation sequencing to improve conservation management of the loggerhead (Caretta caretta) and the green turtle (Chelonia mydas). In the first 2 chapters we used microsatellites and mtDNA to assess the outcome of a reintroduction program of green turtles in the Cayman Islands and the status of the reintroduced wild population. We found that 90% of adult wild females and 80% of wild F1 hatchlings were related to the captive population, proving the program successful. This relatedness did affect negatively the fitness of the wild population. Moreover, we found that after only one generation, genetic differentiation between the populations was significant. Our results suggest that assisted colonisation is a viable solution to the global decline of biodiversity. The third chapter explores the potential of 2b-RAD methodology in the field of non-model species population genomics and provides guidelines to optimise protocol and decision making using 2b-RAD. We discovered that, given the big genome size of the loggerhead turtle, a selective-base ligation should be used to obtain an overall depth of coverage of 20x and make the study cost-effective. The fourth chapter studies the population structure and local adaptation of 9 Eastern Mediterranean loggerhead turtle rookeries using 2b- RAD genomic sequencing. We found a high level of population structure and no overlapping among rookeries. Bayesian clustering indicated our individuals to be grouped in nine genetic clusters, which correspond to the distribution found in the PCoA. We found that atmospheric temperature and geographic location of the rookery have a significant impact on population structure, as outlier loci were found associated with these predictors. These results aim to use fine scale genetic information of the Eastern Mediterranean Sea to inform and improve conservation management of loggerhead turtle rookeries.
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Demanget, Nicolas. "Analyse des performances mécaniques des endoprothèses aortiques par simulation numérique : Application au traitement des anévrismes tortueux." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00784008.
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Le traitement endovasculaire (EVAR) de l'anévrisme de l'aorte abdominale (AAA) vise à mettre en place une endoprothèse (EP) au sein du sac anévrismal afin d'éviter sa rupture. Si cette chirurgie a l'avantage d'être mini-invasive et de pouvoir être utilisée pour des patients non éligibles à la chirurgie ouverte classique, il existe cependant plusieurs événements indésirables, pouvant apparaître au cours du suivi du patient. Mieux connaître le comportement mécanique des EPs permettrait ainsi d'améliorer leur conception et leur durabilité, principaux verrous au recours systématique à l'EVAR. Ainsi, une méthode de modélisation numérique multi matériaux des EPs a été développée. Les modèles numériques d'EPs ont été validés à partir d'une analyse d'images 3D obtenues par tomographie aux rayons X, montrant ainsi leur fiabilité. Les performances mécaniques de plusieurs EPs disponibles sur le marché ont ensuite été évaluées sur différents essais de plus en plus proches des conditions in vivo subies par ces dispositifs. Les EPs ont ainsi été soumises à des essais de flexion pure puis à des essais combinant flexion et pressurisation. La flexibilité des EPs et la réponse mécanique de leurs composants ont été comparées. Il a été montré que l'architecture de l'EP avait une influence significative sur ses performances mécaniques. Enfin, le déploiement des EPs au sein de deux modèles d'anévrismes a été simulé, permettant de mettre en évidence d'autres complications, comme les endofuites de type I. Ces travaux ouvrent ainsi la voie à de nombreuses perspectives, et notamment au développement d'un logiciel d'aide à la décision à destination des chirurgiens.
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Lizza, Kaitlyn. "Historical and Current Population Patterns of the Staghorn Coral (_Acropora cervicornis_) in Dry Tortugas National Park." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5728.
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Acropora cervicornis was once one of the dominant reef building corals of the Caribbean, Florida Keys, and Dry Tortugas (DRTO), but since the 1970’s populations have been decimated throughout their geographic range. Recently, a repopulation was documented through detailed benthic surveys conducted by the U.S. Geological Survey at three locations (Pulaski Shoal, East Key, and Loggerhead Key) within DRTO. Benthic surveys using the U.S Geological Survey’s Along-Track Reef Imaging System (ATRIS) revealed hundreds of previously undocumented colonies.
These discoveries have provided a unique data-set, allowing a comparison between the historical (1883, 1976) and contemporary distributions (2009, 2011) of A. cervicornis. Kernel density estimates were used to analyze shifts in high density areas and non-parametric multivariate analysis of variance tests were used to analyze differences between years in location and extent of the distribution. The results from the KDEs indicated high density areas have shifted among year’s at all three study areas. The comparison of the location and extent of the historical and modern A. cervicornis distributions revealed similarities and differences among years that varied among the study areas. This information is important to the management of this species because it provides vital information on the extent and location of the current distribution relative to historical levels. This study also provides documentation of the population dynamics and ecosystem changes over large time scales within the DRTO region.
The above mentioned dataset was also used in a second study to quantify 1) variations in density among factors such as location (study area), suitable habitat type, and water depth, 2) overall spatial population patterns, and 3) spatial patterns in A. cervicornis density. Results indicated population structure was significantly clustered (P = 0.001) at Pulaski Shoal and Loggerhead Key with areas containing hotspots or significantly higher density (P < 0.05). Although significant hotspots existed, density did not significantly differ among suitable habitat types. Compared to all other factors, water depth had the largest effect on the variation in mean density of A. cervicornis. These findings are vital to understanding the recovery of this species in terms of current habitat and depth associations.
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Chambault, Philippine. "Distribution et comportement de plongée des tortues marines de Guyane française sous l'influence des structures océanographiques." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ030/document.
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La forte hétérogénéité de l'écosystème marin se traduit par une production inégale des ressources sur un large éventail d'échelles spatio-temporelles, qui conditionne par conséquent les déplacements des tortues marines. Considéré comme l’un des plus dynamiques au monde, le plateau des Guyanes est une région très complexe d'un point de vue océanographique et qui héberge trois des sept espèces de tortues marines présentes dans le monde (la tortue olivâtre, la tortue verte et la tortue luth). L'objectif de cette thèse était de comprendre comment les contraintes océanographiques peuvent-elles influencer les déplacements en mer de ces trois espèces. Le déploiement de 55 balises satellites sur des femelles reproductrices en Guyane française a permis de fournir des informations sur leurs trajectoires, sur leur comportement de plongée et sur les caractéristiques de leur environnement. Notre étude a mis en évidence une forte plasticité comportementale interspécifique qui semble être principalement dictée par les traits reproducteurs, les stratégies de reproduction, les conditions locales de l'habitat ou encore les adaptations physiologiques<br>The strong heterogeneity of the marine ecosystem leads to a patchy distribution of the resources in time and space, shaping therefore the movements of sea turtles. Considered as the most dynamic ecosystem in the world, the Guiana shield is a highly dynamic system which hosts three of the seven sea turtle species in the world (the olive ridley, the green turtle and the leatherback turtle). The aim of this thesis was to understand how the oceanographic constraints can influence the at-sea movements of these three species during the reproduction and the migration phases. The deployment of 55 satellite tags on adult females in French Guiana provided information on their trajectories, their diving behavior and on the environment encountered. Our study shows a strong behavioral plasticity between species, which seems to be mainly dictated by the reproductive traits and strategies, the local conditions of the habitat and the physiological adaptations
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France, Guilherme de Jesus. "As origens da Lei Antiterrorismo: os tortuosos caminhos da localização das normas internacionais de combate ao terrorismo no Brasil." reponame:Repositório Institucional do FGV, 2017. http://hdl.handle.net/10438/18496.
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Previous issue date: 2017-04-05<br>A adoção da Lei Antiterrorismo no Brasil representou momento único em sua história e o rastreamento de suas origens depende da compreensão tanto do desenvolvimento das normas internacionais de combate ao terrorismo, quanto das dinâmicas prévias que normas sobre o tema evocaram domesticamente. À luz da teoria da Securitização e da literatura construtivista sobre disseminação de normas, pretende-se delinear o quadro internacional dentro do qual o Brasil se encontrava e como essas normas agiram como elemento de indispensável para que o processo legislativo doméstico se iniciasse. Uma discussão mais ampla sobre a relação do Estado brasileiro com a sua população se faz necessária para que se compreenda a resistência histórica à adoção desse tipo de legislação no país. Especificamente, importa o temor referente à criminalização dos movimentos sociais e reivindicatórios, derivado de experiências históricas diversas, com destaque para o período da ditadura militar. Episódios específicos em que legisladores, bem como operadores do Direito atuaram no sentido de efetivar essa criminalização e reprimir movimentos sociais serão apresentados, com ênfase nas experiências recentes no campo, relacionadas principalmente ao Movimento dos Sem-Terra, e na cidade, referentes às manifestações públicas que se multiplicaram a partir de 2013. Também serão apresentadas as instâncias prévias nas quais se discutiu a elaboração de legislação específica sobre terrorismo. Por si só já constituem uma inédita narrativa acerca desse tema no governo federal, especialmente a partir de 2006, e da relação entre os diversos órgãos interessados no tema, mas com agenda distintas. Identificam-se também muitas das dinâmicas que se repetiriam ao longo do processo legislativo que deu origem à Lei Antiterrorismo. A partir de 2015, teve papel indispensável a pressão exercida pelo Grupo de Ação Financeira, para que se iniciasse esse processo, o qual deve ser compreendido como de localização de normas internacionais sobre terrorismo no Brasil. Recebida essa pressão, desencadeou-se no Poder Executivo, com destaque para o papel do Ministério da Justiça e do Conselho de Controle das Atividades Financeiras, a elaboração de um projeto de lei que atendesse àquelas recomendações, mas não constituísse ameaça aos movimentos sociais. Nesse primeiro momento, já se confrontaram órgãos com interesses diversos, como Ministério Público, Polícia Federal, Forças Armadas, Ministério da Defesa, Agência Brasileira de Inteligência e Gabinete de Segurança Institucional. Enviado ao Congresso Nacional, o PL 2016/2015 foi alvo de profundas alterações conforme parlamentares pretendiam avançar seus interesses diversos e aqueles órgãos se aproveitavam dessa segunda oportunidade para validar seus interesses. Foram os focos dos debates a definição do terrorismo, a introdução de uma excludente que protegesse os movimentos sociais, a criminalização de atos preparatórios e a criação de um mecanismo de coordenação das ações governamentais de prevenção e combate ao terrorismo. A partir da análise de documentos diversos, muitos dos quais inéditos, da literatura nacional e internacional e de mais de 25 entrevistas realizadas com atores envolvidos com esse processo legislativo, buscou-se estabelecer as origens da Lei Antiterrorismo no Brasil.<br>The passing of the Antiterrorism Law in Brazil represents a unique moment in its history. Tracing the origins of said legislation depends on understanding the development of international norms on the fight against terrorism as well as previous instances in which domestic norms on the subject played a role domestically. Using Securitization theory and IR’s literature on norm diffusion, I intend to draw the international normative framework in which Brazil finds itself in order to understand how these norms played an essential part in sparking the legislative process which would result in the Antiterrorism Law. A wider discussion on the relations between the Brazilian State and its population is necessary, however, so that one can understand the historical resistance to legislation of that kind. Especially relevant is the fear related to the criminalization of social movements, derived from various historical experiences, among which I highlight the military dictatorship period. Specific instances in which both legislators and law enforcement officials repressed social movements will be presented, with an emphasis on recent experiences in rural areas (the Landless Rural Workers Movement – MST) and also in urban areas (widespread protests starting in 2013). Previous instances in which efforts were made to produce legislation on terrorism will be detailed as well. On its own, it is the first narrative of its kind, relating the actions inside the federal government, especially since 2006, on the issue. Some of the dynamics identified would also repeat themselves in the legislative process that generated the Antiterrorism Law. In 2015, the actions of the Financial Action Task Force (FATF), which intended to see its Recommendations implemented, were instrumental in setting off said process, which can thus be understood as the localization of international norms on terrorism. Once international pressure was recognized the drawing of legislation began inside the executive branch, where the Ministry of Justice and the Council for Financial Activities Control prevailed in elaborating a bill that suited the FATF’s needs, but did not threaten social movements. In that moment, however, other interests also became apparent, as others inside the government had different agendas – the Armed Forces, the Institutional Security Office, the Brazilian Intelligence Agency, the Federal Police and the Parquet. Once sent to Congress, Bill 2016/2015 suffered deep changes, as congressmen intervened and those institutions attempted, for a second time, to have their interests prevail. Debates focused on a number of specific points such as the definition of terrorism, a provision to safeguard social movements, the criminalization of preparatory acts and the development of a coordination mechanism on terrorism prevention and repression. Drawing on official documentation, some of it previously unseen, international and Brazilian academic works and, especially, on over 25 interviews conducted with people involved in different aspects of the legislative process, I intend to determine the origins of the Antiterrorism Law in Brazil.
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Laurent, Luc. "Une Approche de biologie de la conservation appliquée à la population de tortue marine caretta caretta de Méditerranée." Paris 6, 1993. http://www.theses.fr/1993PA066143.
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La biologie de la conservation d'une espèce est une véritable discipline scientifique. Son champ d'investigation se situe à l'interface des spécialités de la biologie des populations (génétique, dynamique des populations et écologie). Sa méthode consiste à définir des stratégies d'étude d'une espèce et à développer des outils permettant le recensement et l'analyse des menaces, afin de proposer des actions de conservation les plus rentables possibles. Cette méthode a été appliquée à la population de tortue marine caretta caretta de Mediterranée, selon deux approches principales, génétique et de dynamique des populations. L'utilisation d'un marqueur moléculaire (séquence d'une partie d'un gène mitochondrial) a permis d'étudier les flux géniques entrant en Méditerranée et les phénomènes de dispersion écologique. Cette étude a montré que la population méditerranéenne femelle est isolée génétiquement des populations atlantiques, mais que des tortues atlantiques sont trouvées dans le bassin occidental de la Méditerranée. Une modélisation du fonctionnement démographique de la population méditerranéenne a été entreprise, elle a débouché sur la proposition de différents modèles matriciels déterministes. Des analyses de sensibilité ont permis d'estimer les impacts des différentes pêcheries méditerranéennes (captures accidentelles). La mesure de conservation prioritaire est la protection des adultes dans le bassin oriental
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Ferraroli, Sandra. "Etude des déplacements en mer des tortues luths nidifiant sur le plateau des Guyanes : Contribution à leur conservation." Université Louis Pasteur (Strasbourg) (1971-2008), 2004. https://publication-theses.unistra.fr/public/theses_doctorat/2004/FERRAROLI_Sandra_2004.pdf.
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Les activités humaines, en particulier les pêcheries, sont responsables du déclin mondial des populations de tortues marines. Six des sept espèces sont en danger d'extinction. La tortue luth présente la plus vaste répartition géographique parmi les reptiles. Elle doit donc faire face à des conditions océaniques contrastées. La plage d'Awala-Yalimapo en Guyane est le principal site de ponte au monde de la tortue luth. Cependant, depuis 1993, la population décroît. Mes travaux sont en accord avec l'hypothèse d'une mortalité accrue dans les engins de pêche. En effet, le suivi par satellite de femelles entre les pontes successives d'une même saison indique qu'elles utilisent principalement une zone de 40 km de rayon centrée sur 5,9ʿN et 53,9ʿO, transfrontalière avec le Surinam et située dans des eaux peu profondes (<30m). Après la saison de ponte, certaines femelles ont été suivies plus de 16 mois et sur plus de 10000 km. Elles n'utilisent pas de corridors comme ceci a été observé pour d'autres populations de tortues luths. Elles montrent une grande plasticité comportementale avec au moins trois principaux schémas de dispersion : à l'Ouest, au Nord et à l'Est. Contrairement à ce qui a été suggéré par d'autres auteurs, les femelles ne se laissent pas passivement transporter par les courants. Nos résultats suggèrent également que les femelles se nourrissent principalement sur le bord froid des anomalies d'eau chaude observées à méso-échelle. Or, ces zones sont fortement exploitées par les pêcheries ciblées sur le thon et l'espadon. Ceci expose par conséquent les tortues luths à un nouveau risque de captures accidentelles entre deux saisons de ponte. Outre ces aspects de conservation prioritaires, les résultats présentés dans ce travail amènent de nouvelles questions sur des aspects peu étudiés de cette espèce. Notamment concernant les conséquences de la variation des facteurs océaniques sur leur stratégie d'alimentation et de reproduction<br>The main cause of the decline in sea turtle populations is attributed to excess mortality due to coastal and oceanic fisheries. The leatherback sea turtle has the most extensive range and is therefore submitted to variable environmental conditions when at sea. The nesting populations of leatherback turtles in French Guiana are the largest in the world. Since 1993, an alarming decline is observed. Using the Argos satellite system, we have studied the movements of 32 females in relation to oceanographic conditions. Twenty of them were investigated during the nesting period. Our data, obtained since 2000, show that the females remain on the continental shelf between their successive comings ashore for laying. At sea they remain distributed mainly in shallow waters at the border between French Guiana and Surinam, i. E. In a 40 km radius area centred on 5. 9ʿN and 53. 9ʿW. Importantly, their distribution overlaps with the areas used by fisheries, thus favouring incidental catches of sea turtles not only in coastal waters but also on all the continental shelf. Previous works in the Pacific and Indian Oceans have suggested that leatherback turtles use distinct corridors and are passively transported by oceanic currents. Here we show instead that females from French Guiana tracked for up to 16 months and over 10000 km dispersed widely in the Northern Atlantic Ocean. They moreover moved actively in three main directions: west, north and east, and frequently opposing surface currents. In addition, they used different dispersion patterns between years and, from their changes in directions and localizations, they seem to forage on the cold side of warm eddies where industrial tuna fisheries operate. Thus, oceanic routes of leatherbacks do not cross fishing areas by pure coincidence. This study reveals the need of long term, large scale, and pluridisciplinary approaches for conservation of migrating critically endangered species
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Stair, Kristine L. "Assessing the reproducibility of skeletal geochemistry records in Atlantic corals using Montastraea annularis coral heads from the Dry Tortugas, Florida." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0001966.
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Tomás, Aguirre Jesús. "Estudio de la biología de la reproducción de las tortugas marinas del sur de la isla de Bioko (Guinea Ecuatorial)." Doctoral thesis, Universitat de València, 2004. http://hdl.handle.net/10803/10344.
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Cuatro especies de tortugas marinas anidan en la isla de Bioko (Guinea Ecuatorial): la tortuga verde, Chelonia mydas, la tortuga laúd, Dermochelys coriacea, la tortuga olivácea, Lepidochelys olivacea, y la carey, Eretmochelys imbricata. Estas especies realizan sus puestas de huevos en unos 20 kilómetros de playas en el sur de la isla. Debido a la existencia de amenazas de origen humano, es necesario obtener una evaluación del estado de conservación de esta población de tortugas marinas para aplicar medidas efectivas de conservación. En el presente trabajo estudiamos la biología de puesta de las cuatro especies citadas a partir de un programa de marcaje sobre las hembras nidificantes, de muestreos diarios y de recuento de nidos durante dos temporadas de puesta consecutivas, desde octubre de 1996 hasta 1997 y desde septiembre de 1997 hasta marzo de 1998. El área de estudio está formada por seis playas de arena negra volcánica. Las condiciones ambientales en esta zona son extremas, dándose lluvia intensa y tormentas durante todo el año, excepto en una breve estación seca entre enero y febrero. Los dos objetivos principales del presente estudio fueron la descripción de la población de hembras nidificantes y el estudio de su rendimiento reproductivo a partir del análisis y variación del éxito de eclosión. Las recapturas de tortugas marcadas fuera de Bioko nos permitieron analizar también los movimientos migratorios de las tortugas nidificantes hacia sus áreas de alimentación. Dentro del primer objetivo, estudiamos la duración de la temporada de puesta, la distribución de tallas y la estimación del número de hembras nidificantes. La temporada de puesta transcurre desde noviembre hasta febrero, con un pico en diciembre-enero, tanto para las tortugas verdes como para las tortugas laúd y las oliváceas. Las tortugas carey llegarían al área de estudio en el mes de diciembre. Se han detectado emergencias esporádicas de tortuga verde y tortuga laúd fuera de la temporada de puesta descrita. Encontramos una segregación en la distribución de especies, con las tortugas verdes anidando preferentemente en las playas occidentales, con mayor pendiente, y las tortugas laúd en las orientales. Además, las verdes anidaron preferentemente en la zona de vegetación, cuando ésta era accesible. Las tortugas verdes medidas (LCC media= 98.3  6.1; N= 196) fueron, en conjunto, más pequeñas que las de la mayoría de poblaciones nidificantes de esta especie. Las tortugas laúd medidas en Bioko (LCC media= 157.93  14.96) fueron de tallas similares a las de otras poblaciones. Las tortugas oliváceas (LCC media= 71.65  6.42) parecen ser más grandes que las de otras áreas de puesta. Las tortugas verdes de mayor talla parecen llegar antes a anidar en el sur de Bioko. La estimación de tortugas verdes en el área de estudio se realizó a través de un programa de marcaje y recaptura de hembras nidificantes. Empleamos el número medio de puestas por tortuga (2.99 1.82) para obtener una estima de 555 (256-<1681) tortugas verdes en la temporada 1996-97. Debido al reducido marcaje, obtuvimos rangos de las poblaciones de las otras especies de tortugas marinas nidificantes en Bioko empleando valores de número medio de puestas por tortuga y por temporada extraídos de la literatura. El número de tortugas laúd nidificantes en la primera temporada osciló entre 114 y 168. El número de nidos de tortuga verde contabilizados en 1997-98 (1257) comparado con el de la temporada anterior (1671) sugiere que no se produjo un cambio importante en el tamaño poblacional tanto para las tortugas verdes como para las tortugas laúd. Aunque para esta segunda especie, el rango estimado en 1997-98 fue ligeramente superior (156-230 tortugas). Las otras dos especies fueron bastante menos abundantes, entre 19 y 43 tortugas oliváceas y entre 4 y 10 tortugas carey. Un muestreo reciente realizado en el área de estudio por otros investigadores no ha mostrado cambios importantes en el número de nidos de tortugas verdes, oliváceas y carey, aunque sí ha evidenciado un aumento significativo del número de puestas de tortuga laúd. El sur de Bioko parece albergar una de las más importantes áreas de puesta para la tortuga verde en la costa atlántica africana, siendo también un área de puesta importante para la tortuga laúd. Aunque se necesita mayor precisión en las estimas, nuestros resultados parecen suficientes para condicionar la toma de decisiones inmediatas sobre la conservación de estas especies y para realizar comparaciones con estudios futuros en la zona. Abordamos el segundo objetivo a partir de la descripción de los datos relacionados con la producción de neonatos y del análisis de factores bióticos y abióticos que pudieron afectar a estos datos; centrándonos básicamente en la especie de tortuga marina más abundante: la tortuga verde. Para esta especie, el tamaño medio de puesta (número de huevos por nido) fue de 104.3  30.9 (N= 119) en la temporada de 1996-97 y de 112.7  31.5 (N= 83) en la temporada siguiente, sin encontrarse diferencias estadísticamente significativas entre ambas temporadas. Encontramos cierta relación entre el tamaño de puesta y la talla de las tortugas. Los periodos de incubación medios para los nidos de tortuga verde en cada una de las temporadas de estudio fueron superiores a los registrados en la mayoría de las poblaciones nidificantes de esta especie por todo el mundo, debido probablemente a las especiales condiciones climáticas del sur de Bioko. Los porcentajes de éxito de eclosión obtenidos fueron, para 1996-97: 64.3% 25.4, N= 119, y para 1997-98: 75.2% 20.7, N= 83. Encontramos una diferencia significativa entre las dos temporadas, probablemente debido a las diferentes condiciones ambientales registradas. Los porcentajes de éxito de eclosión en el área de estudio fueron similares o ligeramente inferiores a los de otras poblaciones en otras áreas. Observamos que las tormentas esporádicas, las cuales producen reducciones bruscas de la temperatura de incubación, pudieron haber tenido un mayor impacto sobre el desarrollo de los huevos que los factores bióticos y abióticos que definen la temperatura de incubación a lo largo de todo el periodo de puesta. Sin embargo, se deben muestrear más temporadas y controlar otros factores para confirmar los resultados obtenidos. En el presente estudio, identificamos una larga lista de depredadores naturales de las tortugas marinas, de los cuales sólo los cangrejos del género Ocypode parecen tener un efecto significativo sobre los huevos y neonatos. Aunque la tortuga verde es una especie protegida, es explotada en Bioko para consumo humano. Una estimación aproximada del número de neonatos producidos que puedan alcanzar la madurez sexual, a partir de los datos tomados en la temporada 1996-97, reflejó una sobre explotación evidente dadas las capturas que se vienen realizando. Respecto al tercer objetivo, encontramos una dispersión en los movimientos migratorios hacia diferentes áreas de alimentación, tras la puesta. La bahía de Corisco para ser un área de alimentación importante para la tortuga verdes del sur de Bioko.Los resultados obtenidos en el presente estudio deben ser interpretados como un punto de partida para futuros estudios que confirmen las conclusiones descritas.<br>Four sea turtle species nest in 19.4 km of the south coast of Bioko Island (Equatorial Guinea): Chelonia mydas (green turtle), Dermochelys coriacea (leatherbback), Lepidochelys olivacea and Eretmochelys imbricata. The present study summarizes the main aspects of their nesting biology, based on tagging of adult females, nightly surveys and nest census during two nesting seasons. Reproductive success and post-nesting movements are also studied.Main nesting season occurred from October to February, with a peak in December-January. We found some nesting segregation between the two predominant species depending on the characteristics of the beaches. Over 555 (256-<1681) green turtle nesting females were estimated through the mean number of nests (2.99± 1.82) laid by 196 turtles tagged in the 1996-97 season. Nesting leatherbacks ranged from 114 to 230 females. No substantial change in green and leatherback nesting populations were observed in the 1997-98 season. Thus, Bioko Island seems to host one of the most important nesting areas for the green turtle in the atlantic coast of Africa, being also important for leatherbacks. Mean nest size was 107.6 31.1 eggs (N= 216). Mean incubation period (66.15 11.15 days in 1996-97, and 61.81  6.85 days in 1997-98) was found to be higher than those recorded in other green turtle populations all over the world. Significant difference in the hatching success between seasons (1996-97: 64.27 25.35, N= 119; 1997-98: 75.16 20.67, N= 83) was found, probably due to the different climatic conditions registered. Sporadic storms might have higher impact on the egg development than biotic and abiotic factors affecting the incubation temperature along the incubation period. Although green turtle is a protected species, nests and adult females are exploited in Bioko, even though our evaluation of the number of hatchlings that could reach to sexual maturity showed an overexploitation of this resource. Recaptures of tagged turtles showed a dispersal to several foraging areas, being Corisco Bay (Equatorial Guinea) an important foraging area for Bioko nesting green turtles. Further studies must be carried out at Bioko sea turtle nesting beaches to confirm the conclusions set forth here.
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Lilette, Valérie. "Conservation et patrimonialisation de la tortue marine dans le Sud-Ouest de l'océan Indien." La Réunion, 2007. http://elgebar.univ-reunion.fr/login?url=http://thesesenligne.univ.run/07_08_Lilette_pap.pdf.
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À travers une étude comparative de la conservation et la patrimonialisation de la tortue marine aux Comores et dans le sud-ouest de Madagascar, il s'agit de comprendre les processus de convergence ou de divergence qui conduisent à la réussite ou à l'échec des projets et les changements socio-économiques qu'ils impliquent au niveau local. En référence à une idéologie environnementaliste, ces projets de protection de la nature se basent sur les communautés locales pour la gestion des nouvelles réglementations. Ils préconisent le développement de l'écotourisme comme solution à la valorisation des sites naturels ou des espèces phares à protéger. Les motivations des acteurs face à ces projets ne peuvent se comprendre qu'à la lecture des stratégies internes et des institutions dans lesquelles ils évoluent. La comparaison de deux monographies, l'une à Itsamia (Mohéli, Comores) et la seconde à Anakao (Sud-Ouest de Madagascar) vise à présenter les enjeux économiques que suscite la tortue marine (pour sa pêche, ou pour sa valorisation écotouristique), et les renversements de statut que ces phénomènes impliquent (dévalorisation et valorisation de l'animal). L'anthropologie marine, l'anthropologie économique et l'anthropologie du tourisme sont les outils qui nous permettent d'appréhender les stratégies d'affirmation territoriale, le renforcement des identités et l'émergence de nouveaux espaces culturels à l'oeuvre dans ces sociétés de pêcheurs. La valorisation touristique implique une mise à distance des relations naturelles que les hommes entretiennent avec la tortue et nous fait nous interroger sur les rapports que nous entretenons avec la nature, du local au global<br>The comparative study of conservation and heritage of marine turtle between Comoros and south-western Madagascar aims at understanding the process of convergence and divergence leading to the success or failure of projects, and the socio-economie changes they imply on a local scale. These conservation projects are based on the environmental ideology thaf focal communities mariage the new regulations. They recommend the development of eco-tourism as a solution to increase the value of natural sites or flagship species that need protection. The motivations of the different parties involved in these projects cain only be understood after reading the internal strategies an the institutions in which they lake part. The comparison of two monographs, Itsamia (Mohéli, Comoros) and Anakao (South-western Madagascar), aims at presenting the economie stakes induced by marine turties (through fishing, eco tourism valuation), and the shift that these events imply (valuation or devaluation of the animal). Maritime, economie and touristy antropology are tools that allow apprehending strategies of territorial assertion, identity reinforcement and emergence of new cultural spaces in coastal communities. The touristic value implies a distance between human and marine turties, thus making us wonder about the relationship we have with nature, locally and globally
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Lagarde, Frédéric. "Divergences sexuelles dans les stratégies d'histoire de vie de la tortue des steppes (Testudo horsfieldi)." La Rochelle, 2001. http://www.theses.fr/2001LAROS068.
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Les divergences sexuelles dans les stratégies d'histoire de vie ont été étudiées chez la Tortue d'horsfield, Testudo horsfieldi, en Uzbekistan. Nous nous sommes tout d'abord intéressés aux phénomènes de croissance, de maturation et au dimorphisme sexuel de taille et de structure. Les femelles adultes sont plus grandes que les mâles. Ce dimorphisme sexuel de taille en faveur des femelles s'explique par une croissance juvénile plus longue entraînant une maturation plus tardive des femelles par rapport aux mâles. De fortes variations inter-individuelles dans les patterns de croissance et de maturation apparaissent au sein de chaque sexe. En ce qui concerne le dimorphisme sexuel de structure, les mâles développent de façon privilégiée les structures intervenant dans les fonctions de parade, de combat ou de prospection du territoire, les femelles développent les structures contribuant à l'augmentation du volume abdominal et donc de la place disponible pour les oeufs. Nous avons ensuite étudié l'organisation temporelle des comportements, l'écologie alimentaire, l'utilisation de l'espace, la fécondité, et l'écophysiologie de cette espèce. Nos résultats fournissent la première description précise du cycle d'activité de Testudo horsfieldi et des divergences écologiques des mâles et des femelles. Les mâles et les femelles sont capables de réaliser l'ensemble de leur cycle d'activité en 3 mois seulement (mars à juin), période correspondant à la phase végétative des plantes annuelles base de leur alimentation. Au cours de la saison des appariements et de la saison des pontes, l'organisation chronologique des divers comportements et le mode d'occupation de l'espace est spécifique à chaque sexe. Le cadre théorique de l'écologie évolutive nous a permis d'interpréter les stratégies d'acquisition et d'allocation des ressources des mâles et des femelles de cette espèce ectotherme herbivore limitée par le temps<br>The sexual differences in Steppe tortoise (Testudo horsfieldi) life history strategy were studied in Uzbekistan. Firstly, we studied growth and maturation pattern, sexual size dimorphism, and sexual dimorphism in body shape
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Hulin, Vincent. "Etude de l'évolution du déterminisme environnemental du sexe chez les reptiles." Paris 11, 2007. http://www.theses.fr/2007PA112275.
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Certaines espèces de reptiles possèdent un déterminisme du sexe de type génétique, la majorité présentant un déterminisme du sexe sensible à la température d’incubation. La prédominance de TSD chez les reptiles est peu expliquée. J’ai cherché à identifier les avantages évolutifs de TSD par rapport aux autres modes de détermination du sexe des reptiles. J’ai montré avec à un modèle théorique que TSD, par la réalisation de sex-ratios biaisés dépendants de l’habitat, pouvait permettre l’expression de stratégies d’allocation sexuelle évolutivement avantageuses. J’ai ensuite étudié l’impact des changements climatiques sur les populations d’espèces à TSD. En effet, on suppose que ces populations devraient être plus sensibles à ces changements que les populations à GSD. J’ai pu mettre en évidence que les sex-ratios produits par les populations à TSD permettaient l’expression de potentialités évolutives, et que celles-ci pouvaient être reliées aux caractéristiques de TSD. Enfin, j’ai étudié l’histoire phylogénétique de TSD en utilisant une phylogénie des tortues calculée à partir de séquences de gènes mitochondriaux et nucléaires. En utilisant des données issues de la littérature scientifique, j’ai cherché à savoir si l’histoire phylogénétique de TSD pouvait être liée à des modifications des caractéristiques de ce mécanisme de détermination du sexe. Nos résultats ne semblent pas supporter cette hypothèse. Ces différentes études me permettent de conclure que, chez les reptiles, TSD pourrait être un mécamécanisme évolutivement avantageux par rapport à GSD. Son maintien chez ces espèces pourrait aussi être dû à une inertie phylogénétique ou à une quasi-neutralité par rapport à GSD<br>There is a high diversity in sex determination mechanisms among species with sexual reproduction. In reptiles, even if some species show genetical sex determination mechanism (GSD), the majority of species show temperature-dependent sex determination (TSD). The predominance of TSD in reptiles is still enigmatic. I tried to identify the evolutionary advantages of TSD in reptiles, compared to other sex determination mechanisms. First, based on a theoretical model, I have shown that TSD, by producing biased sex-ratios habitat-dependant, could permit the expression of advantageous sexual allocation strategies. Second, I studied the potential impact of global change on populations of TSD species. Indeed, it has been proposed that these populations should be more sensitive to climate change than populations of GSD species. I showed that the sex-ratios produced by TSD populations could permit the expression of an evolutionary potential, and that this potential can be linked to TSD characteristics. Finally, based on a phylogeny of turtle species calculated from mitochondrial and nuclear genes sequences, I studied the phylogenetic history of TSD. With data from the literature, I tried to know if the phylogenetic history of TSD could be linked to modifications of the characteristics of this sex determination mechanism. These differents studies conducted me to conclude that TSD in reptiles could be more advantageous than other sex determination mechanisms. But its maintenance could also be due to phylogenetic inertia, or evolutionary quasi-neutrality, compared to GSD
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Reyes, Grimaldo Sofía Rebeca. "Toxicidad de los sedimentos marinos de las bahías Tortugas-Casma y Paracas sobre juveniles de Argopecten purpuratus (Lamarck, 1819) “concha de abanico”." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/10429.
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Las zonas marino-costeras reciben gran cantidad de desechos antrópicos que conllevan al deterioro progresivo de la calidad del medio ambiente marino, de los cuales muchos se llegan a almacenar en los sedimentos marinos. El objetivo del presente estudio fue estimar los niveles de toxicidad a partir de la concentración letal media porcentual (CL50%) de los sedimentos provenientes de las bahías Tortugas-Casma y la bahía Paracas expuestos por 96 horas sobre Argopecten purpuratus. Estas zonas de estudio presentan alto potencial para el desarrollo acuícola, es así que, esta investigación nos permitirá brindar
información para una adecuada toma de decisiones dirigidas a mejorar la condición del ecosistema y asegurar la sostenibilidad de la acuicultura. Se tomaron muestras de sedimentos de ambas zonas de estudio en dos épocas del año. Las pruebas de toxicidad se basaron en los protocolos descritos por la USEPA. Estas pruebas contaron con un diseño experimental en bloques completamente aleotorizado (DBCA) de cinco concentraciones (100%, 50%, 25%, 12.5% y 6.25%), más un control negativo y cuatro repeticiones por concentración. También, se realizó una prueba de sensibilidad con sulfato de cobre como sustancia de referencia. Los sedimentos marinos de las estaciones evaluadas presentaron
distintos niveles de toxicidad sobre los juveniles de A. purpurtatus, los cuales mostraron nula, baja, moderada y alta toxicidad en las bahías de Tortugas-Casma, mientras que en la bahía de Paracas se observó nula, moderada y alta toxicidad. Asímismo, el estudio mostró que A. purpuratus presentó sensibilidad al sulfato de cobre, con una CL50 de 0.39 mg/L. Finalmente, se recomienda tomar medidas preventivas para las zonas que resultaron toxicas en ambas zonas de estudio, con el fin de mejorar las condiciones del ecosistema y a su vez, asegurar la sostenibilidad de la maricultura y la pesca artesanal.<br>Tesis
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De, Sibio Paula Roberta [UNESP]. "Aspectos ecológicos de um minador foliar em Erythroxylum tortuosum Mart. (Erythroxylaceae): qualidade da planta, anatomia das minas e variação hierárquica de traços vegetais." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/88128.
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sibio_pr_me_botib.pdf: 2783549 bytes, checksum: 29018dc4de13ac01619e66771e6e4e37 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>No presente estudo foram investigados diversos aspectos ecológicos provenientes da interação entre Evippe, um microlepidóptero minador foliar, e Erythroxylum tortuosum, planta típica do Cerrado. Dentre as diversas questões investigadas, este estudo teve três objetivos principais: 1) verificar se a herbivoria provocada pelos minadores pode gerar diferenças na qualidade do recurso, causando variabilidade no sistema; 2) investigar em quais níveis hierárquicos ocorre variações significativas de determinados traços vegetais (químicos e físicos), com e sem a presença de minadores foliares, e 3) determinar se as fêmeas de Evippe apresentam preferência de oviposição por folhas de E. tortuosum com diferenças no teor de água, no nível de assimetria e na área foliar. O teor de nitrogênio decaiu ao longo das fases de desenvolvimento para todos os tipos de tecido (minado, não minado de folha minada e sadio de folha não minada). No caso dos diferentes tipos de folha, diferenças significativas nos valores médios do teor de nitrogênio nas fases intermediária e final foram observadas, em que o tecido minado apresentou os maiores valores médios. Na fase final, o teor de nitrogênio diferiu significativamente para todos os tipos de tecido, e o maior e menor valor médio foram obtidos para os tecidos minados e tecidos sadios de folhas minadas, respectivamente. No caso do conteúdo de taninos, só houve diferença significativa entre os tipos de tecido em folhas minadas. Constatou-se que a maior variabilidade do teor de nitrogênio ocorreu em nível de planta, seguida por tipo de folha, ficando a variável ‘amostras’ com a menor variabilidade. No caso do conteúdo de taninos, o inverso aconteceu, onde a maior variabilidade foi observada em nível de amostra e a menor variabilidade foi verificada em nível de planta. No caso do teor de água...<br>In this study we investigated several ecological questions from the interaction between the leafminer Evippe and Erythroxylum tortuosum, a typical plant from Cerrado. Among all aims, the main questions studied were to: 1) verify whether herbivory by leafminers produces variability in resource quality, causing variability into the system; 2) investigate in which hierarchical levels significant variations of some plant traits (physical and chemical) may occur, with and without leafminers, and 3) determine whether Evippe females show oviposition preference for E. tortuosum leaves with differences in water content, asymmetry levels and leaf area. Nitrogen content decreased throughout leaf development for all leaf tissues (mined, unmined in mined leaf, and healthy tissue in unmined leaf). For all leaf types, significant differences in nitrogen content in intermediary and final developmental phases were observed, in which the mined tissues presented the highest mean values. In the final phase, nitrogen content differed significantly for all types of tissues, and the highest and smallest mean values were verified for mined and healthy tissues from mined leaves, respectively. Tannin contents only presented significant differences between mined and unmined tissues in mines leaves. Large variation in nitrogen content was observed at the plant level, followed by leaf type, and the least variation occurred at the ‘samples’ resolution level. On the contrary, for tannin content large variation occurred at the sample level and least variation was verified at the plant level. For water content the large variability was demonstrated at the plant level, followed by leaf level, and for leaf area, the large variability occurred at the leaf level, followed by plant level. Fluctuating asymmetry was the plant trait that presented large variation at the leaf level. It was concluded... (Complete abstract click electronic access below)
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De, Sibio Paula Roberta. "Aspectos ecológicos de um minador foliar em Erythroxylum tortuosum Mart. (Erythroxylaceae) : qualidade da planta, anatomia das minas e variação hierárquica de traços vegetais /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/88128.
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Orientador: Marcelo Nogueira Rossi<br>Banca: Roberto Antonio Rodella<br>Banca: Kátia Cristina Machado Pellegrino<br>Resumo: No presente estudo foram investigados diversos aspectos ecológicos provenientes da interação entre Evippe, um microlepidóptero minador foliar, e Erythroxylum tortuosum, planta típica do Cerrado. Dentre as diversas questões investigadas, este estudo teve três objetivos principais: 1) verificar se a herbivoria provocada pelos minadores pode gerar diferenças na qualidade do recurso, causando variabilidade no sistema; 2) investigar em quais níveis hierárquicos ocorre variações significativas de determinados traços vegetais (químicos e físicos), com e sem a presença de minadores foliares, e 3) determinar se as fêmeas de Evippe apresentam preferência de oviposição por folhas de E. tortuosum com diferenças no teor de água, no nível de assimetria e na área foliar. O teor de nitrogênio decaiu ao longo das fases de desenvolvimento para todos os tipos de tecido (minado, não minado de folha minada e sadio de folha não minada). No caso dos diferentes tipos de folha, diferenças significativas nos valores médios do teor de nitrogênio nas fases intermediária e final foram observadas, em que o tecido minado apresentou os maiores valores médios. Na fase final, o teor de nitrogênio diferiu significativamente para todos os tipos de tecido, e o maior e menor valor médio foram obtidos para os tecidos minados e tecidos sadios de folhas minadas, respectivamente. No caso do conteúdo de taninos, só houve diferença significativa entre os tipos de tecido em folhas minadas. Constatou-se que a maior variabilidade do teor de nitrogênio ocorreu em nível de planta, seguida por tipo de folha, ficando a variável 'amostras' com a menor variabilidade. No caso do conteúdo de taninos, o inverso aconteceu, onde a maior variabilidade foi observada em nível de amostra e a menor variabilidade foi verificada em nível de planta. No caso do teor de água... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: In this study we investigated several ecological questions from the interaction between the leafminer Evippe and Erythroxylum tortuosum, a typical plant from Cerrado. Among all aims, the main questions studied were to: 1) verify whether herbivory by leafminers produces variability in resource quality, causing variability into the system; 2) investigate in which hierarchical levels significant variations of some plant traits (physical and chemical) may occur, with and without leafminers, and 3) determine whether Evippe females show oviposition preference for E. tortuosum leaves with differences in water content, asymmetry levels and leaf area. Nitrogen content decreased throughout leaf development for all leaf tissues (mined, unmined in mined leaf, and healthy tissue in unmined leaf). For all leaf types, significant differences in nitrogen content in intermediary and final developmental phases were observed, in which the mined tissues presented the highest mean values. In the final phase, nitrogen content differed significantly for all types of tissues, and the highest and smallest mean values were verified for mined and healthy tissues from mined leaves, respectively. Tannin contents only presented significant differences between mined and unmined tissues in mines leaves. Large variation in nitrogen content was observed at the plant level, followed by leaf type, and the least variation occurred at the 'samples' resolution level. On the contrary, for tannin content large variation occurred at the sample level and least variation was verified at the plant level. For water content the large variability was demonstrated at the plant level, followed by leaf level, and for leaf area, the large variability occurred at the leaf level, followed by plant level. Fluctuating asymmetry was the plant trait that presented large variation at the leaf level. It was concluded... (Complete abstract click electronic access below)<br>Mestre
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Faber, Richard James. "Vegetative growth and alkaloid concentration of Sceletium Tortuosum (L.) N.E. Br. in response to different soilless growing media and fertigation regimes in hydroponics." Thesis, Cape Peninsula University of Technology, 2019. http://hdl.handle.net/20.500.11838/3108.
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Thesis (Master of Horticultural Science)--Cape Peninsula University of Technology, 2019<br>The purpose for this study was to investigate whether Sceletium tortuosum was suitable for cultivation in hydroponics and to determine whether different soilless media and fertigation regimes would have an effect on the vegetative growth and alkaloid concentration of the plant. The experiment was conducted over a period of 6 weeks. Three hundred plants were cultivated from one initial mother plant obtained from Verve Dynamics (Pty) Ltd, Somerset West. Twenty treatments were evaluated with 15 sample replicates. Treatments were made up of 4 different soilless growing media, namely: pure silica sand (SS), 50% silica sand with 50% coco-peat (SC), 50% silica sand with 50% vermiculite (SV), and 50% silica sand with 50% perlite (SP). These growing media were tested in conjunction with 5 different fertigation regimes (FR), plants treated with fertigation regime 1 (FR1) received aqueous nutrient solution once every week, fertigation regime 2 (FR2) received aqueous nutrient solution once every second week, fertigation regime 3 (FR3) received aqueous nutrient solution once every third week, fertigation regime 4 (FR4) received aqueous nutrient solution once every fourth week and fertigation regime 5 (FR5) received aqueous nutrient solution once every fifth week respectively.
Chapter 2 reviewed the importance of S. tortuosum and its viability as a Traditional African Medicinal Plant. It was found that S. tortuosum has clear pharmaceutical and economical importance and is one of the only known plants to contain the alkaloids mesembrenone and mesembrine which can be utilized for the promotion of health and treating a variety of psychological disorders such as anxiety and depression.
In chapter 3 it was seen that the various treatments had significant effects in terms of plant root growth, shoot growth and dry weight. Treatment SCFR3 showed the highest individual mean value for root growth, while the average from treatments SVFR1-5 displayed the highest average value. The lowest individual value for root growth was observed in treatment SPFR5. Overall treatments with fertigation regime FR3 had better root growth, while fertigation regimes FR5 showed sub-optimal root growth. For shoot growth the highest individual mean value was found in treatment SVFR1, while the highest average value was observed in treatments SCFR1-5.
In chapter 4 treatments also had a significant effect on alkaloid concentrations. It was observed that shoot extracts contained a higher concentration of total alkaloids than root extracts, however root extracts had an overall higher amount of delta 7 mesembrenone, and mesembrenone in terms of area %, while shoots had higher amounts of mesembrine. Further the mesembrine standard as mentioned in 4.4.5, shoots clearly have an overall higher concentration of mesembrine than roots. These results suggest that roots of S. tortuosum should be harvested for the purpose of extracting delta 7 mesembrenone and mesembrenone molecules, while the shoots should be harvested for extracting mesembrine.
Chapter 5 further investigated the interaction between the vegetative growth and alkaloid concentration of S. tortuosum. There appears to be a clear trend that displays higher concentrations of mesembrine where shoot growth was more optimal, however more optimal growth did not display a higher concentration of total alkaloids. In terms of root growth and total alkaloid concentration, it did not appear that more optimal growth induced higher concentrations of total root alkaloids, meaning reasonable stress on plant root and shoot growth could possibly promote higher concentrations of total alkaloids. It is also clear that overall roots contain more delta 7 mesembrenone and mesembrenone than shoots, suggesting roots should be harvest for extracting these molecules specifically. In most cases high results of delta 7 mesembrenone in roots also had similar amounts of mesembrenone, however certain treatments resulted in higher concentrations of the former and the latter, therefore their similar molecular structure does not always permit similar manifestation in the plant material.
Overall this study has found that S. tortuosum is suitable for cultivation in hydroponics, and that soilless media, fertigation regimes as well as soilless media in conjunction with fertigation regimes affected the vegetative growth and alkaloid concentration of S. tortuosum. This research has shown that some soilless media and fertigation regime treatments had more desirable results in terms of vegetative growth and/or alkaloid concentration of the plant.
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Zumpano, Coacci Julián. "Espacios tortuosos en la última dictadura cívico-militar de la República Argentina (1976- 1983) : Espacio y trauma en la narrativa de Luisa Valenzuela." Thesis, Stockholms universitet, Romanska och klassiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-193900.
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A partir de la teoría del trauma propuesta por Cathy Caruth en los años noventa del siglo pasado, los estudios del trauma volvieron a obtener la atención de la crítica literaria. Si bien el enfoque de Caruth es en primer lugar psicoanalítico se fundamenta también en perspectivas historiográficas y sociológicas. En consecuencia, su teoría nos es muy útil para analizar una selección de obras de Luisa Valenzuela cuya trama se desarrolla bajo la última dictadura militar argentina (1976-1983). Específicamente queremos analizar la influencia que el encierro tiene sobre los personajes, partiendo de un análisis que trabaje conjuntamente tanto la representación del espacio narrativo como la representación del trauma. El método que se utilizará será el de una lectura minuciosa —close reading— de los relatos, articulando las nociones de casa y la dialéctica de lo dentro y lo de fuera de Bachelard para trabajar el encierro en los espacios públicos y privados, por un lado, y una construcción del trauma siguiendo a Caruth desde tres perspectivas psicológicas para entender mejor la tortura, por el otro. De esta forma, nuestra contribución consiste en llevar a cabo una lectura de la obra seleccionada de Valenzuela para poder entender en qué medida el encierro influye sobre el trauma provocado por la tortura durante la época dictatorial.<br>Since the theory of trauma was proposed by Cathy Caruth in the nineties of the last century, trauma studies have once again obtained the attention of literary criticism. Although Caruth’s approach is primarily psychoanalytical, it is also based on historiographical and sociological perspectives. Consequently, her theory is especially useful to the current study when analyzing a selection of works by Luisa Valenzuela, that take place during the last Argentinian military dictatorship (1976-1983). Specifically, it is intended to analyze the influence that confinement has on characters, beginning from an analysis that regards both the representation of the narrative space and the representation of trauma. The method applied will be that of a close reading of the stories, articulating Bachelard's notions of house and dialect of inside and outside to examine, on the one hand, confinement in public and private spaces and, on the other hand, a construction of trauma that follows Caruth’s theory from three different psychological perspectives to better understand torture. Along these lines, this study’s contribution consists of carrying out a reading of Valenzuela's selected literary works, in order to understand to what degree confinement influences the trauma that torture causes during the dictatorship.
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Vásquez, Rivera Felipe. "Biocentro Chinchorro : desembocadura Río San José, Arica." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/169918.
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Attia, El Hili Rahma. "Biogéographie de deux espèces de tortues d'eau douce ( Emys orbicularis et Mauremys leprosa) en Tunisie, diversité génétique des hémoparasites et risque d'introduction parasitaire." Thesis, Perpignan, 2020. http://www.theses.fr/2020PERP0015.
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Cette étude a pour objectifs d’actualiser les données sur la répartition et la variation génétique des deux espèces de tortues d’eau douce Mauremys leprosa et Emys orbicularis en Tunisie et d’évaluer leur vulnérabilité. Elle a également pour but de déterminer la diversité et d’évaluer la spécificité des hémogrégarines (Protozoa: Apicomplexa: Haemogregarinidae) en se basant sur les analyses morphologiques et moléculaires. L’Emyde lépreuse n’est actuellement pas menacée en Tunisie contrairement à la Cistude d’Europe qui est en situation critique. Les analyses morphologiques et moléculaires des parasites sanguins ont permis de montrer la présence de co-infection chez un même individu de tortue. L’aspect moléculaire a concerné la caractérisation et l’identification des espèces appartenant au même genre Haemogregarina à travers l’utilisation des marqueurs mitochondriaux et nucléaires. Ainsi on a pu comparer le degré d’informations génétiques des deux marqueurs et de montrer que le gène mitochondrial COI permettait d’identifier plus de variabilité que celle trouvée avec le gène 18S ARNr. En outre, la faible spécificité de ces parasites sanguins envers les espèces hôtes définitives et intermédiaires, s’est révélée un facteur qui augmente le risque de transmission des hémogregarines d’une espèce hôte exotique vers une espèce hôte indigène<br>The objective of this study is to update data on distribution and genetic variation of t two species of freshwater turtles Mauremys leprosa and Emys orbicularis in Tunisia and to assess their vulnerability. It also aims to determine the diversity and to evaluate the specificity of the hemogregarins (Protozoa: Apicomplexa: Haemogregarinidae) based on morphological and molecular analyzes. The Mediterranean pond turtle is currently not threatened in Tunisia unlike the European pond turtle which is in critical situation. Morphological and molecular analyzes of blood parasites have reveald the presence of co-infection in the same turtle specimen. The molecular aspect concerned the characterization and identification of species belonging to the same genus Haemogregarina through the use of mitochondrial and nuclear markers. Thus we were able to compare the level of genetic information of the two markers and to demonstrat that the mitochondrial COI genes identified more variability than those found with the 18S rRNA gene. In addition, the low specificity of these blood parasites towards the final and intermediate host species has been shown to be a factor which increases the risk of transmission of hemogregarins from an exotic host species to a native host species
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Dalleau, Mayeul. "Écologie spatiale des tortues marines dans le Sud-ouest de l’océan Indien : apport de la géomatique et de la modélisation pour la conservation." Thesis, La Réunion, 2013. http://www.theses.fr/2013LARE0037/document.
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Le déplacement animal joue un rôle déterminant dans la structuration spatiale et la dynamique des populations biologiques, en particulier des espèces fortement mobiles. L’espace et l’environnement font ainsi partie intégrante du cycle de vie des tortues marines. Ce travail de thèse propose de caractériser l’écologie spatiale des tortues marines, du stade juvénile au stade adulte, dans le Sud-ouest de l’océan Indien, principalement par l’usage de deux méthodes : la télémétrie satellitaire et la modélisation individu-centrée. Il montre en premier lieu que la phénologie de la reproduction de la tortue verte à travers la région est principalement liée à la température de surface de la mer au voisinage des sites de reproduction. Sont ensuite étudiés les patrons de dérive des nouveau-nés générés par les courants océaniques qui impacteraient inégalement leurs traits d’histoire de vie selon l’emplacement du site de naissance. Concernant le stade immature, les résultats suggèrent un cycle de développement trans-équatorial pour la tortue caouanne dans l’océan Indien. Pour le stade adulte, cette étude caractérise les couloirs et la connectivité migratoires de la tortue verte dans la région. Enfin, l’intégration de ces résultats permet de comprendre la structuration des patrons migratoires régionaux et leur influence sur la dynamique des populations. L’ensemble des connaissances acquises fournit un support concret d’aide à la décision pour la mise en place de plans de gestion et de conservation des tortues marines dans le Sud-ouest de l’océan Indien. Cela souligne l’importance d’une approche à grande échelle pour la protection d’un patrimoine biologique partagé par plusieurs nations<br>Animal movement is crucial to the ecology of spatially structured population, particularly for highly mobile species. Marine turtles’ life cycle is indeed closely related to spatial and environmental factors. This work analyses the spatial ecology of marine turtles, from early juvenile to adult stages, in the Southwest Indian Ocean, primarily through the use of two methods: satellite tracking and individual-based modeling. Firstly, this analysis argues that green turtle’s reproductive phenology across the region is mainly related to the sea surface temperature in the vicinity of the nesting site. Then, it shows how drifting trajectories of hatchlings in oceanic currents unevenly influence their life history traits depending on the position of the natal site. By tracking late juvenile stage, this work also suggests a trans-equatorial developmental cycle for loggerhead turtle in the Indian Ocean. At adult stage, it describes migratory corridors and connectivity for green turtle across the region. Finally, an integrative approach considering all these results allows for an understanding of the regional migratory patterns and their influence on population dynamics. The results of this work provide a practical policy decision tool for management and conservation of marine turtles in the Southwest Indian Ocean and highlight the need for a large-scale approach in the protection of biological resources and heritage shared by multiple nations
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Pedrono, Miguel. "Gestion interactive entre les populations sauvages et captives : stratégie de conservation de la tortue astrochelys yniphora à Madagascar." Paris 6, 2000. http://www.theses.fr/2000PA066364.
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Un modèle de gestion interactive (GI) entre populations sauvages et captives a été développé pour la tortue a soc astrochelys yniphora, considérée comme étant la tortue terrestre la plus rare du monde. Cette espèce n'est plus représentée que par cinq petites populations vivant au nord-ouest de Madagascar. Son effectif actuel est le résultat de plusieurs siècles d'exploitation commerciale et de sa destruction directe par les feux de brousse. Deux populations sauvages et une population captive ont été caractérisées au niveau démographique. Les paramètres obtenus ont ensuite été utilises pour construire un modèle d'analyse de viabilité de la métapopulation (MVA) d'astrochelys yniphora, a l'aide du logiciel ULM. L'espèce se caractérise par une sensibilité importante de la survie au stade adulte, due en partie a une maturité sexuelle très tardive. L'effectif total de l'espèce en nature a pu être estime a environ 600 (440-770) individus. En présence uniquement de stochasticité démographique toutes les populations continuent a s'accroitre. Par contre, des événements stochastiques de type catastrophe modifient le devenir de ces populations. Tout dépend de la fréquence des catastrophes, de leur importance et de la période de projection retenue. Si les feux de brousse ne peuvent être maitrises, aucune population sauvage n'est assurée de survivre au-delà des deux prochains siècles. La population captive est beaucoup moins sensible aux catastrophes. La maitrise des feux de brousse doit être la première priorité pour réduire la probabilité d'extinction de l'espèce. Dans un deuxième temps, le lâche en nature d'individus nés en captivité est une stratégie de conservation envisageable. Un essai de lâcher de juvéniles issus d'élevage a montre leurs facultés a s'adapter dans leur habitat d'origine. Il est préférable d'affecter ces juvéniles a un programme de réintroduction plutôt qu'a un programme de renforcement des populations sauvages, et de ne réintroduire qu'une seule grande population, plutôt que deux petites. Les MVAs constituent des instruments d'exploration performants, des lors qu'ils s'appuient sur une bonne connaissance des paramètres démographiques des populations qui les composent. Elles permettent de se fixer des objectifs de restauration a atteindre, et fournissent la réponse probable des sous-populations sauvages et captives aux diverses alternatives de gestion. Mais l'aspect le plus intéressant de l'approche metapopulationnelle intégrant les populations sauvages et captives d'espèces emblématiques, réside précisément dans la synthèse qu'elle propose entre la conservation in situ et ex situ. Au-delà du simple rôle de réservoir démographique et génétique, les spécimens d'espèces charismatiques, parapluies, présentes dans les collections zoologiques peuvent ainsi devenir de véritables ambassadeurs de leur communauté biologique originelle en sélectionnant également les candidats a une GI sur des indices de richesse spécifique de leur communauté, il est théoriquement possible d'accroître considérablement le rôle des zoos dans la conservation de la biodiversité.
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Fossette, Sabrina. "Ecologie de la tortue luth, Dermochelys coriacea, en relation avec les conditions océanographiques en Atlantique." Université Louis Pasteur (Strasbourg) (1971-2008), 2008. http://www.theses.fr/2008STR13015.
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