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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.
21

Environmental correlates of vocal communication of wild pygmy marmosets, Cebuella pygmaea

Torre, Stella de la. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin-Madison, 1999. / Typescript. Includes bibliographical references.
22

Study of Nuclear Level Density and γ-Strength Function in <sup>90</sup>Zr, <sup>196</sup>Pt, and <sup>197</sup>Pt

Byun, Youngshin January 2013 (has links)
No description available.
23

Animal welfare in captive Japanese macaques (Macaca fuscata) and pygmy slow lorises (Nycticebus pygmeaus), and human attitudes towards animal memorial ceremonies / 飼育下のニホンザルおよびピグミースローロリスの動物福祉及び動物慰霊祭に対する人間の意識について

Alejandro Pastrana, Josué Samuel 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24468号 / 理博第4967号 / 新制||理||1709(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 Huffman Michael Alan, 教授 古市 剛史, 教授 今井 啓雄 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
24

Pygmy Rabbit (Brachylagus idahoensis) Habitat Use, Activity Patterns and Conservation in Relationship to Habitat Treatments

Lee, Janet E. 27 June 2008 (has links) (PDF)
This study examined activity patterns and habitat use of pygmy rabbits (Brachylagus idahoensis) in mechanically treated and untreated areas in south-central Utah 2005-2008. We monitored fecal pellet plots in continuous sagebrush habitat as well as along treatment edges to record deposition and leporid presence over timed periods. Pygmy rabbit use of big sagebrush was higher than black-tailed jackrabbits (Lepus californicus) and mountain cottontail rabbits (Sylvilagus nuttallii ) (P< 0.01) relative to treated areas (P <0.01). We also compared pygmy rabbit use of areas with continuous sagebrush to residual sagebrush in a sample of mechanically treated areas. Our results suggest a treatment effect with higher (P <0.01) average counts of pygmy rabbit pellets in areas with continuous sagebrush compared to sagebrush strips and islands within treated areas. Before the big sagebrush biotype inhabited by pygmy rabbits is treated to reduce the occurrence and dominance of big sagebrush, we recommend managers consider two options. The first is no treatment, thus preserving, as is, the critical habitat of the pygmy rabbit and other sympatric big sagebrush obligate species of wildlife. The second option cautiously introduces the first prescription of habitat treatment ever recommended in relationship to the pygmy rabbit. This prescription includes recommended widths of the treated areas, seed mixes, widths of the preserved intact big sagebrush habitat for pygmy rabbits as well as suggested grazing systems for domestic livestock. Activity patterns of pygmy rabbits at their burrow were documented through the use of remote cameras. Photographs were analyzed for temporal and seasonal patterns of activity. Our results suggested that time of day was important in the activity level of pygmy rabbits while season was not. Pygmy rabbits were active during all time periods of the day but the greatest levels of activity occurred at night. Numerous other wildlife species were recorded by our remote cameras including other species of leporids, birds, rodents, reptiles and terrestrial predators.
25

Demography and genetic adaptation: examples from human populations

Mendizábal Eceizabarrena, Isabel, 1981- 27 July 2012 (has links)
The human colonization of worldwide landmasses occurred through complex patterns of dispersal and admixture. At the same time, the survival in the different areas of the world depended on the adaptation to new habitats that imposed novel selective challenges. With the advent of high-throughput genotyping technologies and dense catalogues of human genetic variation, the demographic history of many human populations has been unraveled from genomic data, with important implications in medical genetics. However, several human groups are yet to be genetically characterized. These incomplete past histories include the determination of ancestries of the current Cuban population, as well as the origins and dispersal of European Romani, whose demographic history is aimed to be reconstructed in this work. Finally, the present study also aims to describe the genetic basis and evolution of one of the most striking human phenotypes, the African Pygmy height. / La colonización humana de las diferentes masas continentales se produjo mediante complejos patrones de dispersión y mezcla. La supervivencia en las diversas regiones del planeta ha dependido de la adaptación a las presiones selectivas impuestas por los nuevos hábitats. Con el desarrollo de tecnologías de genotipado masivo y las bases de datos de la diversidad genética humana, la historia demográfica de muchas poblaciones humanas, y sus implicaciones médicas, han sido descritas. Sin embargo, algunas poblaciones todavía no han sido caracterizadas genéticamente. Por ejemplo, tanto la descomposición de la ancestría genética de la población cubana actual como los orígenes y la dispersión de los gitanos europeos siguen siendo historias incompletas que se han reconstruido en esta tesis. Finalmente, este estudio también tiene como objetivo describir la evolución y las bases genéticas de uno de los fenotipos humanos más llamativos, la altura de los pigmeos africanos.
26

Sparvugglans (Glaucidium passerinum) invasioner vid Hammarö Fågelstation, Värmland / Invasions of the Eurasian pygmy owl (Glaucidium passerinum) at the Hammarö Bird Station, Värmland, Sweden

Odénius Hedman, Amanda January 2023 (has links)
Sparvugglan (Glaucidium passerinum) är en invasionsfågel som uppvisar årliga fluktuationer i sina invasioner vid Hammarö Fågelstation. Invasioner av denna art utlöses vanligtvis av brist på föda tidigt under hösten, vilket kan orsaka att hundratals fåglar migrerar på ett oförutsägbart sätt. Syftet med denna studie var att undersöka vilka ekologiska faktorer som ligger bakom detta beteende, och om invasioner vid Hammarö Fågelstation sker samtidigt som invasioner i övriga Sverige. Hypoteserna var att 1) sparvugglefångst uppvisar ingen årlig trend vid Hammarö Fågelstation, 2) sparvugglans populationstrender sammanfaller inte med andra ugglors trender, 3) det finns en korrelation mellan sparvugglans populationstrender vid Hammarö Fågelstation och övriga Sverige, och 4) det finns ett samband mellan sparvugglors populationstrender vid Hammarö Fågelstation och årliga fluktueringar i sorkpopulationer samt andra ekologiska faktorer såsom årlig temperatur och snötäcke. Data samlades in från Hammarö Fågelstations årsrapporter över fångst och ringmärkning av migratoriska fågelarter, och data som uppskattar populationstrender över hela Sverige inhämtades från Svensk Fågeltaxering. Korrelationstester utfördes på dessa parametrar mot sorkpopulationer och andra ekologiska faktorer. Studien fann en positiv korrelation mellan sparvugglefångst på Hammarö och populationstrender från hela Sverige under vintermånaderna. Det fanns även en positiv korrelation mellan årliga fluktuationer i sorkpopulationer vid Vindeln och fångst av sparvuggla i Hammarö. Inga korrelationer hittades när sparvugglefångst mättes mot miljömässiga faktorer. Dessa resultat stämmer överens med tidigare litteratur över området, och öppnar för möjligheter till ny forskning gällande miljö- och beteendemässiga aspekter av invasionsmigratoriska mönster, som ännu är en dåligt förstådd aspekt av fågelbeteende. / The Eurasian pygmy owl (Glaucidium passerinum) is an irruptive migrant that shows yearly fluctuations in its invasions at Hammarö Bird Station, Värmland, Sweden. Invasions in this species are usually triggered by a shortage in food supply during early autumn, which can cause hundreds of birds to migrate in an unpredictable manner. The purpose of this study was to explore what ecological factors cause this behaviour, and if invasions at Hammarö Bird Station occur during the same years as invasions in the rest of Sweden. The hypotheses were that: 1) Eurasian pygmy owl captures at Hammarö Bird Station show no inter-annual trend, 2) Eurasian pygmy owl invasions are not correlated with captures of other owl species, 3) there is a correlation between population trends of the Eurasian pygmy owl at Hammarö Bird Station and trends in the rest of Sweden, and 4) there is a correlation between Eurasian pygmy owl captures and annual fluctuations in vole population as well as other environmental factors such as yearly temperature and snow cover. Data was collected from Hammarö Bird Stations annual review of capture and ringing of migratory bird species, and data approximating population trends nationwide were collected from “Svensk Fågeltaxering”. Correlation tests were conducted on these parameters against vole populations and other ecological factors. The study found a positive correlation between owl captures at Hammarö and population trends from all of Sweden during the winter. A positive correlation was also found between annual vole population fluctuations in Vindeln, Västerbotten and owl captures at Hammarö. No correlations were found when measuring owl captures against environmental factors. These results coincide with previous literature on the subject, and open up possibilities for future research regarding the environmental and behavioral aspects of irruptive migration patterns, which is still a poorly-understood aspect of bird behaviour.
27

Altitudinal Effects on The Behavior and Morphology of Pygmy Tarsiers (Tarsius pumilus) in Central Sulawesi, Indonesia

Grow, Nanda Bess 16 December 2013 (has links)
Pygmy tarsiers (Tarsius pumilus) of Central Sulawesi, Indonesia are the only species of tarsier known to live exclusively at high altitudes. This study was the first to locate and observe multiple groups of this elusive primate. This research tested the hypothesis that variation in pygmy tarsier behavior and morphology correlates with measurable ecological differences that occur along an altitudinal gradient. As a response to decreased resources at higher altitudes and the associated effects on foraging competition and energy intake, pygmy tarsiers were predicted to exhibit lower population density, smaller group sizes, larger home ranges, and reduced sexually selected traits compared to lowland tarsiers. Six groups containing a total of 22 individuals were observed. Pygmy tarsiers were only found between 2000 and 2300 m, indicating allopatric separation from lowland tarsiers. As expected, the observed pygmy tarsiers lived at a lower density than lowland tarsier species, in association with decreased resources at higher altitudes. The estimated population density of pygmy tarsiers was 92 individuals per 100 ha, with 25 groups per 100 ha. However, contrary to expectation, home range sizes were not significantly larger than lowland tarsier home ranges, and average NPL was smaller than those of lowland tarsiers. The average home range size for the observed pygmy tarsiers was 2.0 ha, and the average nightly path length (NPL) was 365.36 m. Pygmy tarsiers exhibited a nonrandom, clumped distribution near forest edges. While insect abundance and biomass were found to decrease as altitude increased, insect abundance and biomass was higher along anthropogenic edges. Thus, tarsiers within the study area may mitigate the decreased availability of insects at high altitudes by remaining close to forest edges, which in turn may be related to smaller than expected home range sizes. Further, estimates of pygmy tarsier abundance may be inflated because of increased insect abundance along anthropogenic edges. Contrary to the prediction for smaller group sizes as a response to feeding competition, the observed pygmy tarsiers lived in relatively large groups with multiple adult males. However, in support of the prediction for energetic constraints on body proportions, the observed pygmy tarsiers did not exhibit sexually selected traits. The pygmy tarsiers exhibited low sexual dimorphism and small relative testes mass, a trend opposite from lowland tarsier species, which may indicate a constraint on the development of those traits. Considered together, these results suggest that the observed pygmy tarsiers have adapted to life in an environment with limited resources. Future studies should explore the possible contributing effects of seasonality and topography.
28

Encountering the Mbuti Pygmies : a challenge to Christian mission in the Democratic Republic of the Congo

Musolo W'isuka Kamuha 06 1900 (has links)
This thesis explores the Mbuti Pygmies, a sub-group of the Pygmy peoples, one of the main ethnic groups of the Democratic Republic of the Congo (DRC). The Mbuti Pygmies are settled mostly in the Ituri rainforest, and are, with regard to Christian mission, still unreached and unchurched. The oversight of the churches vis-à-vis these people is highlighted, through this thesis, as a challenge to Christian mission. This challenge is a result of the way Christian mission is understood and undertaken in DRC, namely in the selective and exclusive way of missioning, according to which some peoples are targeted and others forsaken. Churches in the DRC shy away from the Mbuti Pygmies probably because, on the one hand, these forest dwellers belong to the group of Pygmies whose existence as full human beings is enigmatic and very controversial. Because of the uniqueness of the Pygmy peoples in terms of physical features, culture, and way of life, on the other hand, the non-Pygmy peoples, including Christians, suffer from a kind of complex of superiority that creates in them a spirit of discrimination against the Mbuti Pygmies. As the Mbuti Pygmies are discriminated against even by Christians, it is very difficult for them to be taken into account within the mission agendas of the churches. This challenge to Christian mission is highlighted by two facts. Firstly, Christian mission is designed for all the nations to which the Mbuti Pygmies belong. Secondly, the churches, with their missional mandate to all the nations, shy away from the Mbuti Pygmies as if these people were outside the scope of Christian mission and, thus, unworthy of God’s grace and love.To remedy this challenge, with the aim of implementing Christian mission in the DRC, this study suggests a missional encounter as a way forward to addressing the Mbuti Pygmies. In practice, this may be implemented through the missionary conversion, the right perception of the Mbuti Pygmies as being fully made in the “image of God” and fully part of the “all nations”, promoting formal education among the Mbuti Pygmies, and sustaining the churches by an integrated theological education. / Christian Spirituality, Church History & Missiology / D. Th. (Missiology)
29

Encountering the Mbuti Pygmies : a challenge to Christian mission in the Democratic Republic of the Congo

Musolo W'isuka Kamuha 06 1900 (has links)
This thesis explores the Mbuti Pygmies, a sub-group of the Pygmy peoples, one of the main ethnic groups of the Democratic Republic of the Congo (DRC). The Mbuti Pygmies are settled mostly in the Ituri rainforest, and are, with regard to Christian mission, still unreached and unchurched. The oversight of the churches vis-à-vis these people is highlighted, through this thesis, as a challenge to Christian mission. This challenge is a result of the way Christian mission is understood and undertaken in DRC, namely in the selective and exclusive way of missioning, according to which some peoples are targeted and others forsaken. Churches in the DRC shy away from the Mbuti Pygmies probably because, on the one hand, these forest dwellers belong to the group of Pygmies whose existence as full human beings is enigmatic and very controversial. Because of the uniqueness of the Pygmy peoples in terms of physical features, culture, and way of life, on the other hand, the non-Pygmy peoples, including Christians, suffer from a kind of complex of superiority that creates in them a spirit of discrimination against the Mbuti Pygmies. As the Mbuti Pygmies are discriminated against even by Christians, it is very difficult for them to be taken into account within the mission agendas of the churches. This challenge to Christian mission is highlighted by two facts. Firstly, Christian mission is designed for all the nations to which the Mbuti Pygmies belong. Secondly, the churches, with their missional mandate to all the nations, shy away from the Mbuti Pygmies as if these people were outside the scope of Christian mission and, thus, unworthy of God’s grace and love.To remedy this challenge, with the aim of implementing Christian mission in the DRC, this study suggests a missional encounter as a way forward to addressing the Mbuti Pygmies. In practice, this may be implemented through the missionary conversion, the right perception of the Mbuti Pygmies as being fully made in the “image of God” and fully part of the “all nations”, promoting formal education among the Mbuti Pygmies, and sustaining the churches by an integrated theological education. / Christian Spirituality, Church History and Missiology / D. Th. (Missiology)
30

Design, expression and purification of virus-like particles derived from metagenomic studies : Virus-like Particles (VLP) of novel Partitiviridae species, Hubei.PLV 11, and novel Soutern pygmy squid flavilike virus were designed, expressed using the bac-to-bac expression system and then pruified using various methods

Ayranci, Diyar January 2021 (has links)
Viruses are entities which are made of a few genes and are reliant on obligate parasitism to propagate. Due to the obligate connection to their hosts, virus evolution is constrained to the type of host. Viruses however do transmit to evolutionary distinct hosts; in these cases, the phylogenetic relationship of the hosts usually are close. In some instances, RNA-viruses have made host jumps between evolutionary distant hosts, such as the host jump from invertebrates to vertebrates, and fungi to arthropod. Partitiviruses are double stranded RNA viruses which mainly infect fungi and plants. The defining characteristic of these double stranded RNA viruses are the double layered capsids which are formed by a single open reading frame (ORF). The capsid proteins form icosahedral virus particles which are in the magnitude of 30-40 nm. Metagenomic studies have discovered partitiviruses originating from an insect in the Odanata family, a finding which contradicts the fungal host specificity of partitiviruses. The finding of the Hubei.PLV 11 thus implies the existence of a partitiviruses containing structural elements in their capsids which could be involved in the infection of arthropods. Thus, this virus could be used as a model for a structural comparison with its fungi infecting relatives with hopes to identify common viral structural factors necessary for the infection of arthropods. For this purpose, the Hubei.PLV ORF was cloned and then transfected into insect Spodoptera frugiperda (Sf-9) cells using a baculovirus expression system, “bac-to-bac” expression system. The FLAG-tagged capsid proteins were expressed by the Sf-9 cells to be approximately 60 kDa. After ultra-centrifugation in a sucrose gradient, some spontaneous assembly into the expected ~40 nm icosahedral virus-like particles were observed using low resolution scanning electron microscopy. The observed particles were also confirmed by a dynamic light scattering experiment (DLS) and a higher resolution cryo-EM microscope. Thus, the bac-to-bac expression system can be used to produce VLPs from this genus of viruses, and this metagenomically derived virus genome. However, for future success in defining a high-resolution model of this virus, it is recommended that the Sf-9 culture volume is sufficiently high for enough particle production which is necessary for a high-resolution map. The other virus, the Southern pygmy squid Flavilike virus (SpSFV) has been suggested to be the oldest relative of the land based flaviviruses. The SpSFV was found to be the most divergent of the flaviviruses, and to infect invertebrates. Solving for the structure of the SpSFV and comparing it to vertebrate infecting flaviviruses could therefore lead to the identification of factors necessary for the adaptation to vertebrates and thus the humoral immunity by flaviviruses. The soluble E-protein was expressed using the bac-to-bac expression system. The protein was indicated to be multiglycosylated and approximately 50 kDa which is in line with other strains in the genus. Affinity chromatography did not elute this protein, likely due to the His-tag not being spatially available. Cation exchange could elute some protein, but not much from the small ~30 mL culture. To conclude, VLP assembly was confirmed by the Hubei.PLV, thus, solving for the structure is a distinct possibility when a larger Sf-9 culture is used to produce the VLPs. For the SpSFV soluble E-protein, the protein is secreted into the supernatant of the Sf-9 cultures, making purification a possibility. For this, a large Sf-9 culture can be used to produce this protein and then purify it with a cat-ion exchange chromatography.

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