In this thesis, molecular genetic methods were used to study a threatened species, the Eurasian otter. Estimates of population size and population dynamics parameters were obtained, the genetic effects of a restocking program was evaluated, and a population viability analysis was conducted to assess which demographic parameters are most important for the future viability of an otter population. Many of the studies were based on noninvasive genetic sampling of faeces. In the genetic evaluation of the restocking program, it was found that the released otters had contributed to subsequent generations. However, the effects were to a large degree limited to the near surroundings of the release areas. Comparison of two census methods, snow-tracking and noninvasive genetic census based on faeces, showed that approximately only half of the otters detected with the genetic census were found with the snow-tracking census. It is recommended to combine these two methods to obtain the most reliable estimates of population size. A short-term study on population dynamics in otters showed that apparent survival was higher in females than in males and that the rate of addition was also high and likely influenced by migration. The population viability analysis incorporated both genetics and demography and revealed that survival to first reproduction was the most crucial demographic parameter affecting the viability of the study population. This result suggests that conservation efforts should be focused on protocols that enhance the survival prospects of young females. Environmental stochasticity was also found to have large effects on the probability of extinction of this population.

Status and distribution of the Mediterranean monk seal in the northeastern Mediterranean were studied between October 2003 and December 2005. In total, 7 research cruises and 8 research visits were carried out to the region in the study period. The study was generally focused on two regions. First region was mainly around the Cilicia basin in the northeastern Mediterranean where a known Mediterranean monk seal colony (the Cilician colony) inhabits. Second region was around the Gulf of iskenderun where the population status of the monk seals was unknown.In the northeastern Mediterranean, all monk seal caves especially those used for breeding have been checked for whelping and monitored during the study period. In total, 7 pups were found including one death pup in the study period. Observations of the breeding behavior of the species indicated that, whelping also takes place in 2 new caves in addition to the 39 caves already reported for the study area in the earlier studies. Increase in the number of breeding caves showed that the breeding sites of the species has been expanded within the last 5 years. The Cilician colony size was estimated as 30 individuals in 2005. Identification catalog for each individual in the Cilician colony was prepared. Finally, population viability analysis (PVA) for the Cilician monk seal colony was carried out by evaluating the vital parameters of the species, which have been collected since 1994. This analysis was carried out for both pre-conservation phase and the post-conservation phase. In post conservation phase, the survival and fecundity rate of the Cilician colony was found as 0.976 and 0.169 respectively whereas these values were estimated as 0.902 and 0.200 respectively in pre-conservation phase. It was found that there is a 26.9% risk that the monk seal colony abundance will fall below the existing level (30 individuals) at least once during the next 20 years and there is also 0.2% risk that the monk seal colony abundance will fall below 12 at least once during the next 20 years. The risk was found as 21.7% by evaluating the status of the colony in preconservation phase. It was the first PVA study for this species, in which all the parameters used in the analysis were based on the study population, instead of the congeneric Hawaiian Monk Seal. Prior to this study, although monk seals have been frequently sighted by local people in the region, status of the Mediterranean monk seals and presence of the suitable habitats for the species in the Gulf of iskenderun was unknown. Therefore, population status of the Mediterranean monk seal in the Gulf of iskenderun and suitable habitats were investigated. In total, 30 caves were discovered and 7 of them were classified suitable for the Mediterranean monk seal. In addition, a monk seal information network was established in the region in order to gain information about the species especially when the individuals are sighted (alive, injured or death). In total, 51 sighting reports were obtained from local people via the Mediterranean monk seal information network during the study period. Since there are sampling difficulties due to critical status of the Mediterranean monk seal, alternative sampling techniques were investigated in order to find answers to questions related to the monk seal colony inhabiting in the northeastern Mediterranean. For identification of the individuals, comparison of the individuals and monitoring the individuals, 3D model construction technique from photographs was tested as an alternative photoidentification technique for the Mediterranean monk seal. It was found that at least 100 reference points were needed to construct the 3D model of the monk seal.

Rapid development and urbanization of the Lower Florida Keys in the last 30 years has fragmented the habitat of the Lower Keys marsh rabbit (Sylvilagus palustris hefneri) and threatened it with extinction. Current threats exist at multiple spatiotemporal scales and include threats due to development, invasive species, and global climate change. On Boca Chica Key, the Lower Keys marsh rabbit (LKMR) exists as a metapopulation on Naval Air Station-Key West (NASKW). I conducted a population viability analysis to determine the metapopulation's risk of extinction under multiple management scenarios by developing a spatially-explicit, stage-structured, stochastic matrix model using the programs RAMAS Metapop and ArcGIS. These management scenarios include clearance of airfield vegetation, habitat conversion, and control of feral cats as an invasive species. Model results provided the Navy with relative risk estimates under these different scenarios. Airfield clearance with habitat conversion increased extinction risk, but when coupled with feral cat control, risk was decreased. Because of the potential of sea-level rise due to human-induced global climate change, and its projected impact on the biodiversity of the Florida Keys, I estimated the impacts of rising sea levels on LKMR across its geographic distribution under scenarios of no, low (0.3m), medium (0.6m), and high (0.9m) sea-level rise. I also investigated impacts due to 2 treatments (allowing vegetation to migrate upslope and not allowing migration), and 2 land-use planning decisions (protection and abandonment of humandominated areas). Not surprisingly, under both treatments and both land-use planning decisions, I found a general trend of decreasing total potential LKMR habitat with increasing sea-level rise. Not allowing migration and protecting human-dominated areas both tended to decrease potential LKMR habitat as compared with allowing migration and abandoning human-dominated areas. In conclusion, conservation strategies at multiple scales need to be implemented in order to reduce threats to LKMR, such as development, invasive species, and global climate change.

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Made available in DSpace on 2014-10-09T12:46:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:08Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:99/12494-9

Os cimentos de fosfato de cálcio (CFCs) têm atraído grande interesse para uso em ortopedia e odontologia como substitutos para partes danificadas do sistema esquelético, mostrando boa biocompatibilidade e osteointegração, permitindo sua utilização como enxerto ósseo. As características que determinam os CFCs biomateriais atrativos para a reconstituição ou remodelação óssea, são a facilidade de manipulação e moldagem, sem ter de dar forma prévia ao implante, adaptando-se totalmente à forma da cavidade óssea. Diversos estudos, têm mostrado que a adição de aditivos poliméricos tem uma forte influência sobre as propriedades do cimento. A baixa resistência mecânica é o principal obstáculo a uma maior utilização de CFC como material de implante. O objetivo deste trabalho foi avaliar as propriedades de um cimento com base em α-fosfato tricálcico (α -TCP ), adicionado de PVA (poli (álcool vinílico)) (10%, 8%, 6%), hidrogel de PVA (10%,8%,6%) reticulado com ácido cítrico (10%), hidrogel de alginato de sódio (2%) e poliacrilato de amônia (1%), todos em massa, foram adicionados ao pó de α -TCP sintetizado. As amostras foram moldadas e avaliadas quanto à densidade, porosidade, teste ―in vitro‖ (Simulated Body Fluid), fases cristalinas e propriedades mecânicas. Os resultados mostram o aumento das propriedades mecânicas do cimento, quando adicionado destes polímeros. A reticulação dos hidrogéis de PVA com ácido cítrico foi eficiente.O hidrogel de PVA, o hidrogel de alginato de sódio e o poliacrilato de amônia agiram como redutor de líquido. / The calcium phosphate cements (CPCs) have great interest for use in orthopedics and dentistry as replacements for damaged parts of the skeletal system, showing good biocompatibility and osseointegration, allowing its use as a bone graft. The characteristics that determine CPCs attractive biomaterials for bone remodeling or rebuilding, is ease of handling and molding, without having to shape prior to implantation, adapting itself fully to the shape of the bone cavity. Several studies in literature have shown that the addition of polymeric additives has a strong influence on the mechanical properties of cement. The low mechanical strength is the main impediment to a broader use of calcium phosphate bone cement as implant material. The aim of this work was evaluate the strength of a CPC based on α-tricalcium phosphate, with polymeric additions. CPC was synthesized and PVA (poli (vinyl alcohol)) (10%, 8%, 6%), sodium alginate hydrogel (2%) and ammonium polyacrylate (1%), all by weight, were added to the powder. Specimens were molded and evaluated for density, porosity, in vitro test (Simulated Body Fluid), crystalline phases and mechanical properties. The results show the increase of the mechanical properties of cement when added of polymeric additives. The crosslinking of PVA hydrogels with citric acid was effective. The PVA hydrogel, the hydrogel sodium alginate and ammonium polyacrylate acted as a reducing liquid.

Os cimentos de fosfato de cálcio (CFCs) têm atraído grande interesse para uso em ortopedia e odontologia como substitutos para partes danificadas do sistema esquelético, mostrando boa biocompatibilidade e osteointegração, permitindo sua utilização como enxerto ósseo. As características que determinam os CFCs biomateriais atrativos para a reconstituição ou remodelação óssea, são a facilidade de manipulação e moldagem, sem ter de dar forma prévia ao implante, adaptando-se totalmente à forma da cavidade óssea. Diversos estudos, têm mostrado que a adição de aditivos poliméricos tem uma forte influência sobre as propriedades do cimento. A baixa resistência mecânica é o principal obstáculo a uma maior utilização de CFC como material de implante. O objetivo deste trabalho foi avaliar as propriedades de um cimento com base em α-fosfato tricálcico (α -TCP ), adicionado de PVA (poli (álcool vinílico)) (10%, 8%, 6%), hidrogel de PVA (10%,8%,6%) reticulado com ácido cítrico (10%), hidrogel de alginato de sódio (2%) e poliacrilato de amônia (1%), todos em massa, foram adicionados ao pó de α -TCP sintetizado. As amostras foram moldadas e avaliadas quanto à densidade, porosidade, teste ―in vitro‖ (Simulated Body Fluid), fases cristalinas e propriedades mecânicas. Os resultados mostram o aumento das propriedades mecânicas do cimento, quando adicionado destes polímeros. A reticulação dos hidrogéis de PVA com ácido cítrico foi eficiente.O hidrogel de PVA, o hidrogel de alginato de sódio e o poliacrilato de amônia agiram como redutor de líquido. / The calcium phosphate cements (CPCs) have great interest for use in orthopedics and dentistry as replacements for damaged parts of the skeletal system, showing good biocompatibility and osseointegration, allowing its use as a bone graft. The characteristics that determine CPCs attractive biomaterials for bone remodeling or rebuilding, is ease of handling and molding, without having to shape prior to implantation, adapting itself fully to the shape of the bone cavity. Several studies in literature have shown that the addition of polymeric additives has a strong influence on the mechanical properties of cement. The low mechanical strength is the main impediment to a broader use of calcium phosphate bone cement as implant material. The aim of this work was evaluate the strength of a CPC based on α-tricalcium phosphate, with polymeric additions. CPC was synthesized and PVA (poli (vinyl alcohol)) (10%, 8%, 6%), sodium alginate hydrogel (2%) and ammonium polyacrylate (1%), all by weight, were added to the powder. Specimens were molded and evaluated for density, porosity, in vitro test (Simulated Body Fluid), crystalline phases and mechanical properties. The results show the increase of the mechanical properties of cement when added of polymeric additives. The crosslinking of PVA hydrogels with citric acid was effective. The PVA hydrogel, the hydrogel sodium alginate and ammonium polyacrylate acted as a reducing liquid.

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Made available in DSpace on 2014-10-09T12:46:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:08Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Soluções sólidas de CeO2:Gd2O3 foram obtidas a partir de três técnicas de síntese que se utilizam de matrizes poliméricas: técnica dos precursores poliméricos ou citratos, técnica do citrato amorfo e técnica do PVA. O principal objetivo deste trabalho é a obtenção de pós reativos e cerâmicas sinterizadas densas. Para a caracterização dos materiais, foram analisadas as resinas precursoras, o pó calcinado a duas temperaturas e os compactos sinterizados. Os principais resultados mostram que: as soluções sólidas podem ser obtidas a temperaturas relativamente baixas; os pós apresentam tamanho nanométrico de partículas; a densificação é dependente da técnica de síntese e do teor de dopante. A técnica do PVA deve ser utilizada com cuidado, principalmente quando há possibilidade de ocorrer auto-ignição durante a decomposição térmica da resina precursora. Utilizando-se a técnica dos precursores poliméricos, o teor de carbono residual foi mais elevado do que nas outras duas técnicas, como esperado. A técnica do citrato amorfo foi a que permitiu obter cerâmicas mais densas. A resistividade elétrica da cerâmica sinterizada é função do teor de dopante, do teor de pureza e da porosidade, como sugerido na literatura. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:99/12494-9