Bakgrund: Medvetenhet om klimatförändringars påverkan som växt i takt med turismens ökade omfattning har utvecklat ett behov för hållbart resande och en ökad förståelse hos människor om mänskliga aktiviteters negativa miljöpåverkan. Som en utveckling av denna medvetenhet om klimatförändringars påverkan till miljöhot och förlust av biologisk mångfald har djurparker som turistattraktioner fått en allt mer betydelsefull roll. Djurparker, med sina samlingar av djur, har goda förutsättningar för att bevara biologisk mångfald. Djurparker behöver därför bidra till bevarande och djurparkers syfte anses just omfatta bevarande. Tidigare forskning belyser dock att det krävs mer förståelse för vilka bevarandeuppgifter djurparker tar sig an och bidrar med. Syfte och problemformulering: Studiens syfte är att utreda svenska djurparkers bevarandearbete för biologisk mångfald, och besvaras av frågan: På vilka sätt arbetar svenska djurparker med bevarande av biologisk mångfald? Metod: Studien har genomförts utifrån en deduktiv ansats där tidigare forskning har utgjort en grund för studiens forskningsområde. Teoretiska aspekter har testats gentemot studiens empiriska material. Data har samlats in genom telefonintervjuer som genomförts med 19 stycken djurparker belägna i Sverige. Slutsats: Svenska djurparker arbetar med olika bevarandeaktiviteter och i olika stor omfattande grad för att bidra till biologisk mångfald. I samtliga svenska djurparker är djuruppfödning samt information och utbildning de främsta bevarandeuppgifterna. I många djurparker förekommer även arbete med att stödja bevarande in situ, samt att bedriva eller möjliggöra forskningsstudier. Som en förutsättning för bevarandearbetet är turism en betydelsefull faktor eftersom turism bidrar till ekonomiskt stöd och finansiering. Likväl bidrar turism till att besökare kommer till djurparker, vilket är en förutsättning för att djurparker ska kunna sprida information och kunskap som anses vara det mest värdefulla arbetet för att bidra till bevarande av biologisk mångfald.

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Pinnipeds exhibit a wide range of lactation strategies that vary from just a few days to nearly three years in duration. Phocids have a relatively short, intense nursing period culminating with weaning after just a few days or weeks, while dependent otariids generally take several months of consuming a combined milk and solid food diet before being completely independent. The transition to nutritional independence can be particularly challenging for newly weaned pups, which must adjust to behavioral, physiological and nutritional changes as a milk diet is replaced with solid food. An interruption in energy resources during this formative stage could result in a prioritization away from growth, maintenance, or activity resulting in suboptimal development. Three groups of ex situ California sea lion (Zalophus californianus) pups were examined during the initial period of independence after they were weaned at approximately five, seven, and nine months of age. Absolute growth rates of pups were calculated and changes in body composition were estimated using blubber depth measurements and deuterium oxide dilution to determine if weaning age had an effect on subsequent pup development and growth. Blood urea nitrogen and blood glucose levels were observed for their response to changes in body condition, while thyroid hormone levels in the blood were examined as a possible nutritional stress indicator during the pup's transition to solid food. When compared to in situ pups, the 5 month old pups in the present study had significantly greater body mass (39.6 ± 1.6 kg, p < 0.01), axillary girth (85.3 ± 2.9 cm, p < 0.01), and axillary blubber depth (2.3 ± 0.1 cm, p < 0.01) compared to 5 month old in situ pups (26.6 ± 5.2 kg / 70.6 ± 5.34 cm / 1.5 ± 0.2 cm). Nine month old ex situ pups had significantly greater axillary blubber depth (3.7 ± 0.9 cm, p < 0.01) and total body lipid percentage (24.9 ± 4.7%, p= 0.01) than in situ pups (1.5 ± 0.2 cm / 17.1 ± 4.9%). Although all pups in the present study survived the transition to solid food, there were apparent differences in how the different age groups responded physiologically. The five month old pups began the switch to solid food with the lowest overall blubber depth (2.6 ± 0.9 cm) and experienced the greatest change in body mass (-8.5 ± 1.6 kg) and composition while taking the longest to begin physiological recovery (31.7 ± 1.2 d). In contrast, the 9 month old pups entered the transition with more energy reserves (24.9 ± 4.7% TBL), began consuming solid food sooner (16.3 ± 0.6 d), and were able to utilize reserves more efficiently to minimize loss and promote faster growth.

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Diese Arbeit präsentiert Untersuchungen zum Wachstum von GaAs Nanodrähten (NWs) und (In,Ga)As Hüllen mittels Molekularstrahlepitaxie (MBE) mit sekundärem Fokus auf den optischen Eigenschaften solcher Kern-Hülle Strukturen. Das ortsselektive Wachstum von GaAs NWs auf mit Oxidmasken beschichteten Si Substraten wird untersucht, wobei der entscheidende Einfluss der Oberflächenpreparation auf die vertikale Ausbeute von NW Feldern aufgedeckt wird. Basierend auf diesen Ergebnissen wird ein zweistufiger Wachstumprozess präsentiert der es ermöglicht NWs mit dünner und gerade Morphologie zu erhalten ohne die vertikale Ausbeute zu verringern. Für die detaillierte Beschreibung der NW Form wird ein Wachstumsmo- dell entwickelt, das die Einflüsse der Veränderung der Tropfen Größe während des Wachstums sowie direktes des Wachstums auf den NW Seitenwänden umfassend beschreibt. Dieses Wachstumsmodell wird benutzt für die Vorhersage der NW Form über einen großen Parameterraum um geeignete Bedingungen für die Realisierung von erwünschten NW Formen und Dimensionen zu finden. Ausgehend von diesen NW Feldern werden die optimalen Parameter für das Wachstum von (In,Ga)As Hüllen untersucht und wir zeigen, dass die Anordnung der Materialquellen im MBE System die Materialqualität entscheidend beeinflusst. Die dreidimensionale Struktur der NWs in Kombination mit der Substratrotation und der Richtungsabhängigkeit der Materialflüsse in MBE resultieren in unterschiedlichen Flusssequenzen auf der NW Seitenfacette welche die Wachstumsdynamik und infolgedessen die Punktde- fektdichte bestimmen. An Proben mit optimaler (In,Ga)As Hülle und äußerer GaAs Hülle zeigen wir, dass thermionische Emission mit anschließender nichtstrahlender Rekombination auf der Oberfläche zu einem starken thermischen Verlöschen der Lumineszenz Intensität führt, welches durch das Hinzufügen einer AlAs Barrierenhülle zur äußeren Hüllenstruktur erfolgreich unterdrückt werden kann. Abschließend wird ein Prozess präsentiert der das ex-situ Tempern von NWs bei hohen Temperaturen ermöglicht, was in der Reduzierung von Inhomogenitäten in den (In,Ga)As Hüllenquantentöpfen führt und in beispiellosen optischen Eigenschaften resultiert. / This thesis presents an investigation of the growth of GaAs nanowires (NWs) and (In,Ga)As shells by molecular beam epitaxy (MBE) with a second focus on the optical properties of these core-shell structures. The selective-area growth of GaAs NWs on Si substrates covered by an oxide mask is investigated, revealing the crucial impact of the surface preparation on the vertical yield of NW arrays. Based on these results, a two-step growth approach is presented that enables the growth of thin and untapered NWs while maintaining the high vertical yield. For a detailed quantitative description of the NW shape evolution, a growth model is derived that comprehensively describes the NW shape resulting from changes of the droplet size during elongation and direct vapour-solid growth on the NW sidewalls. This growth model is used to predict the NW shape over a large parameter space to find suitable conditions for the realization of desired NW shapes and dimensions. Using these GaAs NW arrays as templates, the optimum parameters for the growth of (In,Ga)As shells are investigated and we show that the locations of the sources in the MBE system crucially affect the material quality. Here, the three-dimensional structure of the NWs in combination with the substrate rotation and the directionality of material fluxes in MBE results in different flux sequences on the NW sidefacets that determine the growth dynamics and hence, the point defect density. For GaAs NWs with optimum (In,Ga)As shell and outer GaAs shell, we demonstrate that thermionic emission with successive nonradiative recombination at the surface leads to a strong thermal quenching of the luminescence intensity, which is succesfully suppressed by the addition of an AlAs barrier shell to the outer shell structure. Finally, a process is presented that enables the ex-situ annealing of NWs at high temperatures resulting in the reduction of alloy inhomogeneities in the (In,Ga)As shell quantum wells and small emission linewidths.

Le problème de l’accès aux ressources génétiques des plantes pour la sélection variétale est au cœur de la Révolution Verte. A partir des années 1960, les sélectionneurs font de la disparition des variétés locales sous l’effet de la diffusion de nouvelles variétés génétiquement homogènes un problème public à l’échelle mondiale. Dans une perspective qui croise la recherche d’archives et l’enquête de terrain, cette thèse revient sur la formation de ce problème, sur sa trajectoire historique et ses enjeux actuels. Il s’agit d’analyser l’hétérogénéité des savoirs scientifiques et des approches qui sont développés sur le thème de la conservation des ressources génétiques dans les arènes internationales. L’étude des débats et des initiatives menés dans le cadre de la FAO permet de comprendre quels sont les savoirs légitimés, lesquels sont marginalisés et comment la nature et les contours du problème ont été négociés. La place que les ressources génétiques occupent au cours d’épisodes clés de la Révolution Verte est également au cœur de ce travail. Cette thèse analyse spécifiquement l’importance accordée aux variétés locales de maïs dans le programme agricole que la Fondation Rockefeller met en place au Mexique à partir de 1943. Alors que le maïs hybride est généralement présenté comme un vecteur de la modernisation agricole, cette thèse montre que les experts sont confrontés à l’échec du paradigme d’amélioration variétale qu’ils étaient censés exporter. Face à une innovation uniquement applicable à une échelle très limitée, les semences paysannes du maïs restent l’option variétale la plus utilisée au Mexique. Ce travail montre que ce sont bien les choix pragmatiques des agriculteurs qui constituent le fondement de la conservation, de facto, des ressources génétiques du maïs dans ce pays. / The issue of access to plant genetic resources for plant breeding is at the heart of the Green Revolution. Beginning in the 1960s, the disappearance of local varieties with the spread of new genetically homogeneous varieties evolved into a public problem on a global scale. Combining archival research and field investigations, this thesis explores the emergence of this problem, its historical trajectory, and its current forms. I analyze the heterogeneity of scientific knowledge and approaches to the conservation of genetic resources developed in international arenas. An exploration of debates and initiatives within the framework of the FAO sheds light on the issues of which knowledges are legitimated and which marginalized, and on how the nature and outlines of the problem have been negotiated. An examination of the role of genetic resources in key episodes in the Green Revolution is also central to the study. The thesis specifically analyzes the importance attributed to local maize varieties in the agricultural program that the Rockefeller Foundation implemented in Mexico beginning in 1943. While hybrid maize is generally presented as a vector of agricultural modernization, this thesis shows how experts were faced with the failure of the varietal improvement paradigm that they were supposed to export. As hybrid maize is an innovation that is only applicable on a very limited scale, farmers’ maize seeds still are the most widely used varietal option in Mexico. The study shows that it is indeed the pragmatic choices of farmers that form the basis for the de facto conservation of the country’s maize genetic resources.

Le développement de photocatalyseurs en couches minces supportées constitue un intérêt majeur autorisant une séparation efficace des produits de réaction, en dépit d’une réduction de leur surface spécifique par rapport à des nanopoudres du même matériau. La synthèse de revêtements de TiO2 par pulvérisation cathodique magnétron en condition réactive fait l’objet de recherches intensives. Cette technique permet de contrôler, à travers les paramètres d’élaboration, la structure et les propriétés physicochimiques et photocatalytiques des revêtements.Afin de s’affranchir de la contamination du catalyseur par le sodium du verre lors de traitements en température ou lors de recuits de couches déposées à l’ambiante, une barrière de diffusion en SiNx est intercalée et son épaisseur est fixée pour la suite de l’étude. Différentes couches de TiO2 ont été élaborées à haute pression dans un réacteur doté d’un système de contrôle en boucle fermée basé sur la spectroscopie d’émission optique. L’effet de la cristallisation in situ à différentes températures sur les différentes propriétés des revêtements TiO2 a été étudié et les propriétés de ces derniers ont été comparées à celles des échantillons synthétisés sur des substrats froids et recuits ex situ aux mêmes températures.Enfin, des premiers travaux portant sur l’influence de l’introduction de l’argent en différentes teneurs sur l’efficacité photocatalytique sous lumière visible des couches de TiO2 cristallisées in situ et ex situ sont présentés. / The development of supported photocatalysts thin films is of major interest allowing an efficient separation of the reaction products, in spite of their specific area reduction compared to nanometric scale powders. The synthesis of TiO2 coatings by reactive magnetron sputtering is the subject of intensive researches. This technique allows, trough the control of the deposition parameters, to manage the structure and the physicochemical and photocatalytic properties of the coatings. In order to hinder the sodium contamination of the catalyst from the glass substrate, either during in situ or ex situ heating of the coating, a SiNx diffusion barrier is intercalated with a fixed thickness. Different layers of TiO2 were prepared at high pressure in a reactor equipped with a closed-loop control system based on optical emission spectroscopy. The influence of the in situ crystallization at different temperatures on the properties of the TiO2 coatings was studied. These properties were compared with those of samples synthesized ex situ and at the same temperatures. Finally, first studies on the influence of silver enrichment at different contents on photocatalytic activity under visible light of TiO2 layers crystallized in situ and ex situ, are presented.

Orientador: Mario Luiz Teixeira de Moraes / Resumo: The spatial distribution pattern of tree species is one of the most important factors for the understanding of the ecological interrelationships occurring in a population or community forestry, it is vital to the understanding of how a certain species uses the resources available to establish and reproduce in a given space. Interpretation of the results of the spatial analysis of tree species provides significant subsidies for the understanding of these phenomena and indication of individuals for genetic conservation programs and forest promotion. In this context, the objective of the work was to study the spatial distribution of six natural populations of arborea specie baru (Dipteryx alata Vogel.) using the Moran index associated with a Geographic Information System and descriptive statistics of their silvicultural attributes. These populations are located in the municipalities of Paulo de Faria/SP, Campina Verde/MG, Ituiutaba/MG, Brasilândia/MS, Campo Grande/MS e Itarumã/GO. All populations had a growth over 45 cm in relation to the DAP (Diameter at Breast Height) attribute. Taking into account that the DAP attribute has a higher dendrochronological correlation, the estimated age of these natural populations would be in the range between 40 and 63 years. As regards the calculation of Moran index, populations of Ituiutaba and Itarumã presented random spatial distribution pattern, pointing high variability among its individuals, so the collection of seeds for ex situ conserv... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / One of the challenges in the conservation of genetic resources is the identification of areas for collection, maintenance and preservation of seeds, especially recalcitrant, for in situ and ex situ conservation. Thus, through four articles is intended to identify areas with potential naturally occuring mangaba using modeling techniques by Maxent software using environmental variables, as well as to characterize the morpho-genetic diversity using local and scientific knowledge by the analysis of fruits, and conservation of seeds in order to guarantee the viability in the storage. It is observed distribution of populations intensively on the coast, with higher occurrence in the municipalities of Greater Aracaju and Japoatã, Pacatuba, Nossa Senhora das Dores, Malhador, Estancia, Arauá and Itabaianinha. To evaluate the traditional knowledge of the catchers of mangabas inserted into remaining forests, five associations were selected (Baixa Grande, Pontal, Porteiras, Riboleirinha and Manuel Dias). It was observed that the classification of fruit occurs according to color and there are differences among the collection locations for morphometric and physical- chemical (pH, titratable acidity, soluble solids) traits. Baixa Grande seeds (Pirambu-SE) were stored at 10 ° C in polyethylene glycol 6000 to -0.8 MPa and it was observed that viability can be maintained until the third month. Four natural population (111 individuals) were evaluated by of molecular markers ISSR. The population of Baixa Grande presented the highest number of observed and effective alleles (1.99 and 1.61). The number of polymorphic loci was 71 (95% Polymorphism). The differences in morphological characteristics of mangaba can be used for selection of genotypes. The information resulting from this research are subsidies for management and conservation aiming to increase the diversity of mangaba in the state of Sergipe. / Um dos desafios na conservação dos recursos genéticos é a identificação de áreas para coleta, manutenção e preservação de sementes, especialmente as recalcitrantes, visando à conservação in situ e ex situ. Assim, por meio de quatro artigos, se propõe identificar regiões com potencial ocorrência natural de mangaba por meio de técnicas de modelagem pelo programa Maxent empregando variáveis ambientais, bem como caracterizar a diversidade morfo-genética empregando o conhecimento local e científico por meio da análise de frutos, e conservar as sementes de forma a garantir a viabilidade no armazenamento. Observa-se a distribuição das populações mais intensamente no litoral, com maior ocorrência nos municípios da Grande Aracaju e Japoatã, Pacatuba, Nossa Senhora das Dores, Malhador, Estância, Arauá e Itabaianinha. Para avaliar o conhecimento das catadoras de mangabas inseridas em remanescentes florestais, foram selecionadas cinco associações (Baixa Grande, Pontal, Porteiras, Riboleirinha e Manuel Dias). Observou-se que a classificação dos frutos ocorre de acordo com cor e diferenças entre as localidades de coleta para características morfométricas e físico-químico (pH, acidez titulável, sólidos solúveis). Sementes de mangaba de Baixa Grande (Pirambu-SE) foram armazenadas à 10ºC em polietilenoglicol 6000 à -0,8 MPa e constatou-se que a viabilidade pode ser mantida até o 3° mês. Quatro populações naturais de mangaba (111 indivíduos) foram avaliadas por meio de marcadores moleculares ISSR. A população de Baixa Grande foi a que apresentou maior número de alelos observados e efetivos (1,99 e 1,61). O número de locos polimórficos foi de 71 (95% de polimorfismo). As diferenças observadas nas características morfológicas de mangaba podem ser utilizadas para a seleção de genótipos. As informações resultantes desta pesquisa são subsídios para manejo e conservação visando ampliar a diversidade de mangaba no estado de Sergipe.