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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Comportamento de arara-azul-de-lear (Anodorhynchus leari, Bonaparte, 1856) em cativeiro e a influência da técnica flocking na interação de pares

Favoretto, Gabriela Rodrigues 22 June 2016 (has links)
Submitted by Caroline Periotto (carol@ufscar.br) on 2016-10-10T15:06:40Z No. of bitstreams: 1 DissGRF.pdf: 3437375 bytes, checksum: 6462dc22eaf7cf1e73ecf9875bbef4d9 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:50:19Z (GMT) No. of bitstreams: 1 DissGRF.pdf: 3437375 bytes, checksum: 6462dc22eaf7cf1e73ecf9875bbef4d9 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:50:26Z (GMT) No. of bitstreams: 1 DissGRF.pdf: 3437375 bytes, checksum: 6462dc22eaf7cf1e73ecf9875bbef4d9 (MD5) / Made available in DSpace on 2016-10-20T19:50:32Z (GMT). No. of bitstreams: 1 DissGRF.pdf: 3437375 bytes, checksum: 6462dc22eaf7cf1e73ecf9875bbef4d9 (MD5) Previous issue date: 2016-06-22 / Outra / The Lear's Macaw (Anodorhyncus leari) is an endemic parrot of northeastern Bahia state, classified as endangered mainly due to the destruction of their habitats and wildlife trade. It was recently discovered in the wild, and few studies are known for this species. Understanding behavioral patterns of species threatened by extinction is essential for developing effective conservation strategies. Here we describe the behavioral repertoire of a group of this species maintained by the São Paulo Zoological Park Foundation. We carried out observations between October 2014 and February 2015, totaling 348 hours of sampling effort through ad libitum continuous record, in two different environmental conditions, both in in pairs and in flock. We described 60 behavioral states, grouped in categories maintenance, locomotion, feeding, social, stereotyped, reproductive and alert. We also found five patterns of vocalization (alarm, contact, cohesion, reproduction and imitation). Most of the behaviors described for other species is also reported here to A. leari, more similar to A. hyacinthinus. We discuss the differences in order to contribute to the formulation of a behavioral profile for this species, and with information that may assist in maintaining normal behavior in captivity. / A arara-azul-de-lear (Anodorhyncus leari) é um psitacídeo endêmico da caatinga do nordeste do estado da Bahia, classificada como em perigo de extinção em decorrência principalmente da destruição do seu habitat e do tráfico de animais silvestres. Foi descoberta na natureza a relativamente pouco tempo, sendo escassos estudos sobre a espécie. A compreensão de padrões comportamentais de espécies ameaçadas é fundamental para a elaboração de estratégias conservacionistas eficientes. O presente trabalho teve como objetivo o levantamento do repertório comportamental de um grupo de indivíduos da espécie mantidos pela Fundação Parque Zoológico de São Paulo. As observações ocorreram entre outubro de 2014 e fevereiro de 2016, totalizando 348 horas de esforço amostral através de amostragem ad libitum de registro contínuo com caráter qualitativo em duas condições ambientais distintas, tanto na manutenção dos indivíduos em pares quanto em bando, resultando na descrição de 60 condutas comportamentais dentro das categorias manutenção, locomoção, alimentação, social, estereotipado, reprodutivo e alerta, além de cinco padrões de vocalização (alarme, contato, coesão, reprodução e imitação). A maioria dos comportamentos descritos para outras espécies é relatada para A. leari, com maior semelhança com A. hyacinthinus. Porém as diferenças são discutidas com o objetivo de contribuir com a formulação de um perfil comportamental para a espécie e com informações que possam auxiliar na manutenção de comportamentos naturais em cativeiro.
2

Biologisk behandling av oljeförorenad jord : Abiotiska faktorers inverkan och effekter av olika uppläggningssätt på nedbrytningshastigheten. / Biological treatment of oil contaminated soil : The effect of abiotic factors and how the soil is structured at site.

Svensson, Sofia January 2015 (has links)
The purpose of this report was to investigate how the abiotic factors (temperature, pH, nutrients, oxygen levels and water content) would affect the decomposition of oil-contaminated soil and how a variance in structured soil would affect the decomposition-rate. A minor field-study was made and soil where structured in five different ways (one was a default pile and was used as a reference). The study took place over 137 days and three samples were taken (start, middle, end) and analyzed for aromatic and aliphatic compounds. The result of this study shows that there is a significant difference between all methods for the aliphatic compounds and no significant difference for the aromatic compounds. The abiotic factors that affect decomposition vary from organism to organism, depending on what type of environment it will function the best. In this type of environment it could be necessary to change temperature interval, nutrient availability or pH to optimize the conditions for the microorganisms. The conclusion of this report is that the structured of the soil-piles will affect decomposition rate, but it is unsure how much. Further research is needed to conclude how the soil should be structured to maximize the decomposition-rate.
3

Interactions Sol-Plante dans un contexte de phytomanagement de sols pollués par des métaux : application à Miscanthus x giganteus / Soil-plant interactions in the context of phytomanagement of soil contaminated by metals : application to Miscanthus x giganteus

Al Souki, Karim Suhail 05 May 2017 (has links)
Alentours de l'ancienne fonderie de Pb Metaleurop Nord, Miscanthus x giganteus a accumule peu de Pb et Cd dans ses organes aériens. Les expériences ont été menées pour évaluer la capacité de la plante à améliorer la fonctionnalité des sols contaminés, étudier les impacts à long terme des débris de feuilles massives sur le système sol-plante et déterminer les impacts des contaminants sur la santé de la plante en première et deuxième années de culture. Cinq sols été échantillonnés à différentes distances de la fonderie. Le plus loin est situé à 75 km. Trois cultivars été utilisés. Les résultats ont confirmé la tolérance des plantes aux métaux, et montré des effets positifs de la culture sur les activités biologiques du sol. Une tendance favorable été notée pour la teneur en carbone organique et la capacité d'échange de cations. L'incorporation de débris a conduit une évolution favorable de certains paramètres physicochimiques et biologiques. Sur une période de trois à six mois après l'addition, aucun effet n'a été observé sur l'extrabilité, la phytodisponiblité de Cd et Pb et la santé d'une culture modèle (raygrass). En outre, les résultats des biomarqueurs du stress de la première récolte démontré l'existence d'un stress oxydatif aux miscanthus cultivés sur le sol avec plus de 500 mg Pb kg-1. À la fin de la deuxième année, le stress oxydatif était plus présent et apparaissait sur les plantes dans le sol avec plus de 200 mg Pb kg-1. Cela s'explique par les contraintes des conditions expérimentales (la culture dans les conteneurs souligner les interactions entre les métaux et le système racinaire). Enfin, aucune différence n'a été observée entre les cultivars étudiés. / In the vicinity of the former lead smelter Metaleurop Nord, Miscanthus x giganteus been shown to accumulate little lead and cadmium in its aerial organs. Pot experiments were led to assess the plant ability to ameliorate the functionality of metal contaminated soils, study the long-term impacts of massive leaf debris on the soil-plant system and determine the contaminants impacts on miscanthus health in the first and second cultivation years. Five soils were sampled at different distances from the foundry. The furthest is located 75 km away. Three miscanthus cultivars were used. Results confirmed the plant tolerance to metals. They showed positive effects of culture on the soil biological activities. Favorable trend was noted for organic carbon content and cation exchange capacity. The foliar debris incorporation in soil led to favorable evolution of certain physicochemical and biological parameters. Over a period of three to six months after the debris addition, no effect was observed on the extractability, phytoavailability of Cd and Pb, and health of a model culture, ryegrass. Moreover, the stress biomarkers results obtained during the first harvest demonstrated the existence of oxidative stress in miscanthus grown on soil with more than 500 mg Pb kg-1. At the end of the second year, oxidative stress was markedly more present and appeared on plants obtained on soil with more than 200 mg Pb kg-1. This is explained by constraints resulting from the experimental conditions (cultivation in containers emphasizes the interactions between the metallic elements and the root system). Lastly, no significant difference was observed between the cultivars studied.
4

The influence of carotenoids on fitness related traits in anurans : implications for ex situ conservation

Ogilvy, Victoria January 2011 (has links)
Amphibians are facing an extinction crisis, and in many cases it has become necessary to conserve species in captivity. Unfortunately, our understanding of the nutritional requirements of amphibians in captivity is currently limited. There have been anecdotal reports that captive bred amphibians have duller skin colouration than wild members of the same species. Many amphibians use carotenoid pigments in skin colouration. Carotenoids are yellow-red pigments synthesised by photosynthetic tissues, however vertebrates cannot synthesise them de novo and rely entirely on dietary sources. Reduced colour in captive bred amphibians could therefore result from limited carotenoid availability in the diet. Limited access to carotenoids could have further negative consequences on health and reproductive success since carotenoids are known to function in the immune, antioxidant and reproductive systems of other vertebrate taxa. The role of carotenoids in amphibian fitness is currently unknown, and the aim of this PhD was to assess the importance of carotenoids to anuran amphibians. Skin colour may be influenced by carotenoid availability, and it was therefore important to establish a suitable method for quantifying skin colour in amphibians. In Chapter 1 I assessed two methods for colour quantification, including digital photography and spectrometry. Neither method was significantly more accurate than the other, however I chose to use photography for my studies for reasons of practicality. In Chapters 2 and 3 I assessed the role of carotenoids in the reproductive systems of wild frogs. I found that carotenoid-based skin colouration was involved in the breeding behaviour of wild Agalychnis moreletii frogs. I found positive assortative mating by colour in that frogs were found mating with individuals with similar carotenoid-based colouration. This assortative mating by colour may be driven by mutual mate choice, or may have evolved to prevent mismatched pairing with a sympatric and phenotypically similar species (A. callidryas). I then analysed the carotenoid composition of eggs produced by wild A. moreletii and Phyllomedusa trinitatis, which are tree frogs with similar reproductive ecology but different egg deposition strategies: Agalychnis moreletii deposits green eggs on the surface of leaves while P. trinitatis wraps pale cream eggs in leaves. The concentration and diversity of carotenoids was significantly higher in A. moreletii than P. trinitatis and potential ecological explanations for this are discussed. In Chapter 4 I investigated carotenoid availability in the diet of captive amphibians by analysing the carotenoid composition of commonly used feeder-invertebrates. I assessed interspecific variation in carotenoid accumulation in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus), which were all fed one of three diets (wheat-bran, fish-food based diet, fresh fruit and vegetables). All three cricket species were a poor source of carotenoids unless they were gut-loaded on a carotenoid-rich diet. Nutrient retention over a two-day period was poor across species. Finally, there were significant interspecific differences in gut-loading capacity, with G. bimaculatus having the greatest capacity. This study shows that carotenoid availability to captive amphibians will be limited unless they are fed specific feeder invertebrate species, recently gut-loaded on carotenoid-rich foods. In Chapters 5, 6 and 7 I assessed the influence of carotenoids on fitness related traits in captive anurans. I firstly assessed colour degradation in captive-reared A. moreletii frogs and looked at whether skin colour could be improved through increased carotenoid availability in the diet. I found that carotenoid-based skin colour degraded quickly in captivity but could be improved through dietary supplementation with carotenoids, however there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Next, I investigated the effect of carotenoids on larval growth and development, and post-metamorphic growth, development, skin colour and reproductive success in captive A. callidryas frogs. I found no direct effect of carotenoids during larval stages, however there were carry-over effects on post-metamorphic growth and skin colour. Increased post-metamorphic carotenoid availability positively influenced growth, skin colour and reproductive success. Similarly to A. moreletii, there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Finally, I examined the protective potential of carotenoids in Silurana (Xenopus) tropicalis tadpoles that were exposed to ultraviolet (UV) light. Exposure to UV light significantly reduced tadpole survival and there was no evidence that carotenoids afforded any protection. Nevertheless, in tadpoles that were not exposed to enhanced UV light, carotenoids increased survival. Furthermore, carotenoids had a significantly positive effect on the developmental rate of tadpoles in both UV limited and UV enhanced environments. The studies in this PhD show that carotenoid availability has important consequences on fitness related traits in anuran amphibians, which include effects on growth, skin colour, reproductive success and survival. Carotenoid availability to captive amphibians will, however, be low unless they are provided with feeder invertebrates that have been recently gut-loaded on carotenoid-rich foods. These findings should be considered when recommendations are made on the nutritional requirements of amphibians in captivity as they could significantly improve the fitness of captive-bred individuals, and thus increase the success of ex situ conservation programmes.
5

Právní úprava ochrany zvířat ex situ v USA a ČR / Legal Regulation of Animal Protection Ex Situ in USA and the Czech Republic

Štíbrová, Andrea January 2015 (has links)
Legal Regulation of Animal Protection Ex Situ in USA and the Czech Republic This thesis aims to compare the legislation of animal protection ex situ in the Czech Republic and USA. The content is systematically divided in two sections. First section focuses on different law systems, which is international, national and local legislation. Second section explains the law used in different institutions that provide ex situ protection, such as zoos, aquariums, wildlife sanctuaries, etc. The thesis describes different legal approaches and uses several examples for a practical comparison. In its conclusion the thesis sums up the negatives and positives of each legislation and their overall quality and efficiency. The thesis also points out some of the desirable solutions to some current problems and a possible development in the area.
6

Variação genética entre e dentro de populações de dipteryx alata vog. para caracteres morformétricos de plântulas, frutos e sementes / Genetic variation between population and inside of dipteryx alata vog. for character morformétricos seedlings, fruit and seeds

Luz, Kelly Cristina da [UNESP] 02 September 2016 (has links)
Submitted by KELLY CRISTINA DA LUZ null (kellynha_luz@hotmail.com) on 2016-11-02T21:42:31Z No. of bitstreams: 1 Kelly Cristina da Luz Final.pdf: 1753561 bytes, checksum: ff74f3975a428e6703ecf23e56e0c45d (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-11-10T12:33:48Z (GMT) No. of bitstreams: 1 luz_kc_me_ilha.pdf: 1753561 bytes, checksum: ff74f3975a428e6703ecf23e56e0c45d (MD5) / Made available in DSpace on 2016-11-10T12:33:48Z (GMT). No. of bitstreams: 1 luz_kc_me_ilha.pdf: 1753561 bytes, checksum: ff74f3975a428e6703ecf23e56e0c45d (MD5) Previous issue date: 2016-09-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dipteryx alata é considerada uma espécie endêmica do Cerrado brasileiro. Atualmente a espécie necessita de atenção pelo aumento da fragmentação da área de ocorrência. Destaca-se por apresentar madeira resistente e pela a alta produção de frutos. O objetivo do estudo foi estimar os parâmetros genéticos a partir dos caracteres morfométricos dos frutos, sementes e plântulas, de modo a fornecer informações da variabilidade genética existente dentro e entre as procedências da espécie para futuros programas de melhoramento genético e para a conservação. Os frutos foram coletados em três populações naturais, Campo Grande - MS, Ituiutaba - MG e Paulo de Faria – SP, em outubro de 2014. As mudas foram preparadas no viveiro da Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). Para as análises morfométricas dos frutos e sementes, foram mensurados a largura (mm), espessura (mm), comprimento (mm) e massa (g). Nas plântulas foram avaliadas a altura total (cm) e o diâmetro do coleto (mm). Foi utilizado o delineamento blocos completos (DBC) com uma planta por parcela. Observou-se diferenças significativas entre procedências e progênies para os caracteres dos frutos, sementes e plântulas, indicando a presença de variação genética. Os resultados da herdabilidade média, coeficiente de variação individual e acurácia, indicaram que para os frutos, sementes e plântulas há presença de variabilidade genética. Na análise em conjunto das plântulas pode-se verificar que houve diferenças significativas para o efeito de procedência e não significativa para o efeito de progênie. Resultados indicam que esses materiais podem ser utilizados para a conservação genética da espécie e para o melhoramento genético. / Dipteryx alata is considered endemic species of the Brazilian Cerrado. Currently the species needs attention by the increased fragmentation of the occurrence area. It stands out for presenting resistant wood and the high production of fruits. The aim of the study was to estimate genetic parameters from the morphometric fruits, seeds and seedlings, to provide information of genetic variability within and between species provenances for future breeding programs and conservation. The fruits were collected in three natural populations, as Campo Grande - MS, Ituiutaba - MG and Paulo de Faria - SP, in October 2014. The seedlings were prepared in the nursery Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). For morphometric analysis of fruits and seeds were measured (mm) thickness (mm) Length (mm) Mass (g). In the seedlings were evaluated the total height (cm) Stem diameter (mm). We used the design complete block design (RBD) with one plant per plot. There were statistically significant differences among provenances and progenies for the characters of fruits, seeds and seedlings, indicating the presence of genetic variation. The results of the average heritability coefficient of individual variation and accuracy, indicated that for the fruits, seeds and seedlings there is presence of genetic variability. In the analysis of all the seedlings can be seen that there were significant differences in the effect of origin and not significant for the effect of progeny. Results indicate that these materials may be used for genetic conservation of species and genetic improvement.
7

Variação genética entre e dentro de populações de dipteryx alata vog. para caracteres morformétricos de plântulas, frutos e sementes /

Luz, Kelly Cristina da January 2016 (has links)
Orientador: Miguel Luiz Menezes Freitas / Resumo: Dipteryx alata is considered endemic species of the Brazilian Cerrado. Currently the species needs attention by the increased fragmentation of the occurrence area. It stands out for presenting resistant wood and the high production of fruits. The aim of the study was to estimate genetic parameters from the morphometric fruits, seeds and seedlings, to provide information of genetic variability within and between species provenances for future breeding programs and conservation. The fruits were collected in three natural populations, as Campo Grande - MS, Ituiutaba - MG and Paulo de Faria - SP, in October 2014. The seedlings were prepared in the nursery Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). For morphometric analysis of fruits and seeds were measured (mm) thickness (mm) Length (mm) Mass (g). In the seedlings were evaluated the total height (cm) Stem diameter (mm). We used the design complete block design (RBD) with one plant per plot. There were statistically significant differences among provenances and progenies for the characters of fruits, seeds and seedlings, indicating the presence of genetic variation. The results of the average heritability coefficient of individual variation and accuracy, indicated that for the fruits, seeds and seedlings there is presence of genetic variability. In the analysis of all the seedlings can be seen that there were significant differences in the effect of origin and not significant for the effect of progeny. Results indicate t... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
8

Vnímání krásy savců v ZOO Praha: vliv věku a vzdělání respondentů / Perception of beauty of mammals in Prague ZOO: Influence of respondents' age and education

Poláková, Petra January 2016 (has links)
1 Abstract Every year, the number of species considered as endangered increases, especially due to human activities. Nowadays, captive breeding in zoological gardens becomes an option for their survival in refugees. Zoological gardens function as so-called "Noah's Ark", which has the potential to shelter a large amount of individuals from many species. In the future, this opportunity may give us a chance to reintroduce a species that disappeared in the nature. There are many factors influencing which species will be selected to be kept in zoos, e.g., the IUCN status, taxonomical uniqueness, availability, etc., but it was found that especially the size of the animal and the human aesthetic preferences affect the selection. However, every group of animals is evaluated independently in the terms of beauty, and thus, it is necessary to detect these rules and then to apply them to conservation projects. This thesis examines the factors that influence human aesthetic preferences to mammals, both in terms of the characteristics of animals (their colour and morphology), and in terms of human factors (gender, age, education, residence). It was found that especially the pattern, saturation and overall lightness of the animal affect the evaluation of beauty in mammals. On the other hand, dark colours are evaluated...
9

Développement de méthodes ex-situ de dopage de nanofils semiconducteurs IV / Development of ex-situ doping methods of group IV semiconductor nanowires

Fakhfakh, Mariam 31 January 2018 (has links)
L’objet de cette thèse est d’étudier le dopage ex-situ de nanofils semiconducteurs IV pour des applications en électronique, spintronique ou encore thermoélectricité. Deux techniques de dopage ont été explorées : l’implantation par faisceaux d’ions et le Spin-On-Doping (SOD).L’implantation d’ions Mn a été testée dans les nanofils de Ge avec l’objectif de synthétiser un matériau semi-conducteur ferromagnétique dilué. Une concentration en Mn de quelques pourcents peut être atteinte sans amorphisation du fil ni formation de précipités, ce qui est très encourageant. Lors d’expériences d’implantation réalisées in situ dans un microscope électronique en transmission, une forte exaltation de la pulvérisation sous irradiation électronique a été constatée.La technique SOD consiste à faire diffuser thermiquement les impuretés de type p ou n contenues une résine de type HSQ (Hydrogen silsesquioxane) qui enrobe les nanofils. Le recuit de la HSQ (dopée ou non) engendre une modification structurale des nanofils (bien que cette technique soit considérée comme non destructive). Lors du recuit, une transformation partielle de la phase diamant 3C vers la phase hexagonale 2H, a en effet été observée dans les nanofils de Si et de Ge, au-delà de 500 et 400°C respectivement. Les paramètres essentiels de la transformation de phase sont la contrainte de cisaillement résultant de la densification de la résine et le budget thermique. Les nanofils de Ge deviennent amorphes au-delà de 650°C, ce qui interdit en pratique leur dopage par SOD.Les caractérisations électriques ont été réalisées sur des nanofils de Si réalisés par gravure ionique réactive sur substrats orientés (111) et contactés en matrice ou individuellement. Pour le contactage de nanofils uniques en configuration NW-FET (nanowire field effect transistors), un procédé technologique basé sur la lithographie électronique a dû être développé. Les difficultés à surmonter étaient relatives à la faible longueur des nanofils. Diverses techniques de caractérisation ont été mises en œuvre (I-V en configuration verticale ou horizontale de type TLM (Transient Linear Measurement), SSRM (scanning spreading resistance microscopy), EBIC (electron beam induced current). Les mesures collectives concernent des ensembles de nanofils de type p enrobés dans une résine qu’elle soit dopante ou non. Pour observer un courant notable dans la structure, un recuit est nécessaire. Au-delà d’une température de recuit de 600°C, une polarisation négative du substrat induit un comportement conforme au mécanisme SCLC (space charge limited current) attendu pour des nanofils faiblement dopés enrobés dans une matrice isolante. En positif, on observe une caractéristique I(V) ohmique et une densité de courant jusqu’à 500 fois plus élevée dans les nanofils que dans le substrat. Ce comportement pourrait être dû à l’influence des états d’interface provenant de la technique de gravure. Cette hypothèse est confortée par le fait qu’après recuit à 900°C, le courant en direct s’explique en considérant dans les fils un dopage proche de celui du substrat, et surtout par l’observation en SSRM d’une couche conductrice interfaciale entre fils et HSQ. Elle permet aussi d’interpréter les mesures sous pointes faites sur les fils de type n. Le mode de transport SCLC a également été observé pour des nanofils individuels contactés sous pointe ou par lithographie. Ces mesures n’ont pas mis directement en évidence l’influence de la transformation de phase.Le dopage de type n ou p par SOD s’avère efficace après recuit à 900°C. Dans ce cas, les comportements observés, contacts ohmiques et jonctions p-n, peuvent être interprétés plus simplement en considérant des niveaux de dopage supérieurs à 3×10¹⁶ cm⁻³ en type p et 2×10¹⁶ cm⁻³ en type n. Ces valeurs déduites des résistivités mesurées sont sans doute très sous-estimées puisque la mobilité dans les fils est sans doute inférieure à celle du volume. / This thesis aims at studying the ex-situ doping of semiconducting nanowires (NWs) for applications in electronics, spintronics or thermoelectricity. Two widely used techniques have been envisaged: ion beam implantation and Spin-On-Doping (SOD).The ion beam implantation of Mn ions has been tested in Ge NWs in an attempt to form a 1D diluted magnetic semiconductor structure. A Mn concentration of few percents can be achieved without amorphization of the nanowire nor clustering, what is very promizing. During implantation done in situ in a transmission electron microscope, a strong enhancement of the sputtering under electron irradiation has been observed.The doping by SOD results from the thermal diffusion of p-type or n-type impurities contained in a HSQ (Hydrogen silsesquioxane) resist in which the NWs are embedded. The curing of the HSQ resist (doped or not) leads to a structural modification of nanowires (while SOD is generally assumed to be non-destructive). As a result of the annealing, a partial transformation of the 3C diamond phase towards the 2H hexagonal phase is observed in Si and Ge nanowires, above 500 et 400°C respectively. The main parameters of that phase transformation are the shear stress due to the HSQ densification and the thermal budget. Ge NWs are found to turn to amorphous above 650°C, what renders SOD practically unusable for Ge NWs. Two methods are currently used for the fabrication of nanowires, the VLS (vapor-liquid-solid) growth and reactive ion etching of (111) Si wafers. For practical reasons, etched NWs were used for the study of their electrical properties.The electrical characterizations were done on arrays of Si NWs embedded in a HSQ matrix or on single NWs. For contacting single NWs in the NW-FET(nanowire field effect transistors) configuration , a process based on electron beam lithography has been developed. The issues to be solved were related to the low length of NWs. Various measurement techniques were used: I-V in two tips or TLM (Transient Linear Measurement) arrangement, SSRM (scanning spreading resistance microscopy), EBIC (electron beam induced current). Collective measurements were done on arrays of p-type NWs embedded in a HSQ resist, doped or not. It was firstly observed that an annealing is needed to observe a noticeable current in the structure. Above an annealing temperature of 600°C, for a negative bias applied to the substrate, the observed behavior can be described by the SCLC (space charge limited current) mechanism expected for poorly doped NWs in an isolating matrix, while a positive bias applied to the substrate results in an ohmic characteristic and in a current density up to 500 times higher in the NWs than in the substrate. This unexpectedly high intensity in direct bias may be attributed to electrically active surface states resulting from the etching process. This hypothesis is conforted by the fact that an annealing at 900°C (without extra doping) the measured intensity can be explained by assuming the same doping level in NWS than in the substrate. In addition, an interfacial conductive between resist and nanowires can be observed by SSRM. These interfacial states can be also involved for understanding the measurements done on n-type NWS. The SCLC mechanism of transport has been also observed for single NWs contacted by tips or by lithographied contacts. These measurements were not able to evidence the effect of the phase transformation on the electrical properties.P-type and n-type doping by SOD becomes effective after annealing at 900°C. After doping, ohmic or rectifying behaviours on p-type substrate are observed as expected. That renders more easy the interpretation of results, by assuming doping levels in the NWs of 3×10¹⁶ cm⁻³ and 2×10¹⁶ cm⁻³ for p-type and n-type respectively. These values as deduced from resistivities are probably very underestimated as the mobilities in NW are probably much lower than in the bulk.
10

Etograma de mico-leão-preto (Leontopithecus chrysopygus, Mikan, 1823) em cativeiro, com ênfase no comportamento reprodutivo

Oliveira, Mayara Ferreira de 26 June 2016 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2016-10-13T12:14:46Z No. of bitstreams: 1 DissMFO.pdf: 4743699 bytes, checksum: 0ed61a6d2874b421280f1f898f2d1a0c (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T13:08:28Z (GMT) No. of bitstreams: 1 DissMFO.pdf: 4743699 bytes, checksum: 0ed61a6d2874b421280f1f898f2d1a0c (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T13:08:38Z (GMT) No. of bitstreams: 1 DissMFO.pdf: 4743699 bytes, checksum: 0ed61a6d2874b421280f1f898f2d1a0c (MD5) / Made available in DSpace on 2016-10-21T13:08:48Z (GMT). No. of bitstreams: 1 DissMFO.pdf: 4743699 bytes, checksum: 0ed61a6d2874b421280f1f898f2d1a0c (MD5) Previous issue date: 2016-06-26 / Outra / The interest in knowing and observing animals increased the habit of keeping them in captivity, starting the creation of zoos around the world. They have being modernized through the time and acquiring a new concept in education and research, in which the conservation of the species is placed in the foreground. The research in captivity cover many areas of study, such as parasitology, pathology, genetics, and more, allowing closer contact with the animal and making it easier to access the information that is difficult to get in nature. However, the study of animal behavior stands out among these areas, as it collaborates with several researches, allowing a more detailed knowledge about the behavioral characteristics of the species, as described in this study. Populations of black lions tamarins (Leontopithecus chrysopygus) kept in captivity are targets of researches that aim to get more information about the species, helping their conservation. The preparation of a detailed behavioral catalog for the species was the objective of this article, emphasizing the description and analysis of reproductive and socio-reproductive behavior. Took part in the first stage of the study four couples of captive black lions tamarins in an extra section of the São Paulo Zoo. In the second stage, there were more four captives couples from the Conservation Center of Wild Fauna of the State of São Paulo (CECFAU), where two of them also belonged to the previous group. The observations lasted four months in each study area and were held from Ad libitum methods to make the ethogram (90 full observation hours) and focal animal with instant registration, with 30-minute sessions and 1-minute intervals for frequency analysis. It was also analyzed the use of the grounds of the using area (divided into quadrants) and the proximity of the animals, which have resulted in a high frequency of use of the upper quadrants in the sections of the Sao Paulo Zoo, as well as the holding area and plays in facilities of the CECFAU, being noticed, in both areas, the animals away from each other most of the time of the observation. Forty-five different behavioral acts were detected, divided into 11 behavioral categories to make the analysis of the frequencies easier. The categories most performed by the animals were Locomotion, Food and Physiological behavior for couples of the Sao Paulo Zoo, as well as for couples CECFAU, except for the category “Not visible” that showed high representativeness for this latter individuals, corroborating the frequency that the animals stay in holding area and burrows, where they were out of the observer's reach. In Reproductive and Socio-reproductive behaviors were observed "copulation", "smell genital”, "hold behind", "copulation simulation" and "genital markings". It is suggested non-invasive endocrine studies, by analyzing fecal metabolites concentrations that, associated with observations of behavior, can certainly help the reproductive study of the species. / O interesse em conhecer e observar animais fez com que o costume de mantê-los em cativeiro aumentasse, dando início à criação de zoológicos pelo mundo. Estes foram se modernizando ao longo do tempo e adquirindo um novo conceito em educação e pesquisa, em que a conservação das espécies é colocada em primeiro plano. A pesquisa em cativeiro engloba diversas áreas de estudo, tais como parasitologia, patologia, genética, entre outras, permitindo um contato mais próximo com o animal e facilitando o acesso a informações de difícil obtenção na natureza. Entretanto, o estudo do comportamento animal se destaca entre essas áreas, já que colabora com várias pesquisas possibilitando um conhecimento mais detalhado sobre as características comportamentais da espécie, assim como é descrito neste estudo. Populações de micos-leões-pretos (Leontopithecus chrysopygus) mantidos em cativeiro são alvos de pesquisas que têm por objetivo adquirir maiores informações sobre a espécie, contribuindo para a sua conservação. A elaboração de um catálogo comportamental detalhado para a espécie foi o objetivo deste trabalho, dando ênfase à descrição e análise dos comportamentos reprodutivos e sócio-reprodutivos. Participaram da primeira etapa do estudo quatro casais de micos-leões-pretos cativos no setor extra do Zoológico de São Paulo. Na segunda etapa, mais quatro casais cativos do Centro de Conservação da Fauna Silvestre do Estado de São Paulo (CECFAU), sendo dois deles também pertencentes ao grupo da etapa anterior. As observações tiveram duração de 4 meses em cada área de estudo e foram realizadas, a partir dos métodos Ad libitum, para a confecção do etograma (90 horas de observação total) e Animal focal com registro instantâneo, com sessões de 30 minutos e intervalos de 1 minuto, para as análises de frequência. Também foi analisada a utilização da área de uso do recinto (dividido em quadrantes) e a proximidade dos animais, que tiveram como resultado uma alta frequência da utilização dos quadrantes superiores nos recintos do Zoológico de São Paulo, bem como o cambiamento e toca nos recintos do CECFAU, sendo visualizado, em ambas as áreas, os animais distantes entre si na maioria do tempo de observação. Foram registrados 45 atos comportamentais diferentes, divididos em 11 categorias comportamentais visando facilitar a análise das frequências. As categorias mais executadas pelos animais foram Locomoção, Alimentação e Comportamentos Fisiológicos para os casais do Zoológico de São Paulo, bem como para os casais do CECFAU, com exceção para a categoria Não Visível que apresentou alta representatividade para estes últimos indivíduos corroborando com a frequência da permanência dos animais nos cambiamentos e tocas, onde ficaram fora do alcance do observador. Dentre os comportamentos Reprodutivos e Sócio-reprodutivos foram observados “cópula”, “cheirar genitália”, “segurar por trás”, “simulação de cópula” e “marcações genitais”. Sugere-se estudos endócrinos não invasivos, mediante a análise das concentrações de metabólitos fecais, que associada às observações dos comportamentos, certamente podem auxiliar o estudo reprodutivo da espécie.

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