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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

A comparative study of male-male relationships in chimpanzees (Pan troglodytes) and bonobos (P. paniscus) / チンパンジーとボノボのオス間関係の比較研究

Shibata, Shohei 23 March 2023 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24466号 / 理博第4965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)教授 古市 剛史, 准教授 Huffman Michael Alan, 教授 今井 啓雄 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
2

Three technical challenges facing advanced fuel cycle closure

Van der Hoeven, Christopher Ainslie 05 August 2010 (has links)
Many technical hurdles remain to be overcome before an advanced fuel cycle in which minor actinides from spent nuclear fuel are used to generate power. Three such issues were addressed: criticality safety of minor actinides as compared to currently used fissile isotopes; accuracy of evaluated nuclear data for selected minor actinide high energy fission cross-sections; and the preliminary design optimization of a minor actinide burning/breeding fission blanket in a fission fusion hybrid reactor concept. For minor actinide compositions found in spent fuel, current safety measures for actinide solutions were found to be adequate, though concerns may remain for unmoderated transuranic materials. Additionally, computational results indicated a 5-10% error in the fission cross-section of some minor actinides above the fast fission threshold. Finally, a relatively tall annular fission blanket was found to be the most ideal configuration for the UT fission- fusion hybrid reactor concept, satisfying criticality and power output criteria. / text
3

Fission-fusion sociality in dusky dolphins (Lagenorhynchus obscurus), with comparisons to other dolphins and great apes

Pearson, Heidi Christine 10 October 2008 (has links)
I examined fission-fusion sociality in dusky dolphins (Lagenorhynchus obscurus), and investigated aspects of social convergence between dolphins and great apes. I used boat-based group focal follows and photo-identification to collect data in Admiralty Bay, New Zealand during 2005-2006. I used generalized estimating equations to examine relationships between party (group) size, rate of party fission-fusion, activity, and location; and relationships between leaping frequency and behavior. Using photo-identification images from 2001-2006, I analyzed the strength and temporal patterning of associations, short- and long-term association patterns, preferred/avoided associations, and behaviorally-specific preferred associations. To analyze social convergence between dolphins and great apes, I compared female bottlenose dolphin (Tursiops spp.) and chimpanzee (Pan troglodytes) social strategies through literature review. I conducted 171 group focal follows, totaling 157 observation hours. Mean party size was 7.0±6.0 individuals. Party size changed every 5±.47.6 min on average. The most frequent activity was resting (37%), followed by traveling (29%), foraging (18%), and socializing (15%). Foraging was positively related to party size and rate of fission-fusion. Near mussel farms, foraging increased, traveling decreased, and rate of party fusion increased. "Clean" leaps were the most frequent leap type (84%) and were positively related to party size and foraging. Noisy and coordinated leaps were positively related to party size; noisy leaps were negatively related to foraging. Associations during 2001-2006 (N = 228 individuals) were nonrandom for 125 days; associations within one field season were nonrandom for 60 days. Individuals formed preferred/avoided associations during most years. The strongest associations occurred during foraging and socializing; the weakest associations occurred during traveling. Individuals formed preferred associations during foraging, resting, and socializing. Review of female bottlenose dolphin and chimpanzee sociality revealed that: 1) females form weaker bonds and are less social than males, 2) females associate mostly with other females, 3) mothers are often alone with their offspring, 4) mothers (vs. non-mothers) and non-cycling (vs. cycling) females associate less with males, and 5) non-cycling (vs. cycling) females occur in smaller parties. Female dolphins may be more social than female chimpanzees due to decreased scramble competition, increased predation risk, and decreased cost of transport for dolphins vs. chimpanzees.
4

Investigation of Group Leadership in a Fission-Fusion Species, the Bottlenose Dolphin

Lewis, Jennifer S 16 July 2010 (has links)
Consistent leadership of group travel by specific individuals has been documented in many animals. Most species exhibiting this type of leadership have relatively stable group membership. Animals using fission-fusion grouping are not expected to use specific leaders because associations would not be frequent. Certain conditions, however, may allow this type of control over group travel to occur. First, a population would need to be small enough to allow regular associations between individuals. Second, leadership may be useful if the environment where the population in question lives is complex and requires learning to access the resources efficiently. To determine whether fission-fusion species existing under these conditions utilize specific individual leadership, I examined a small residential population of bottlenose dolphins (Tursiops truncatus) in the Lower Florida Keys (LFK) where the benthic habitat is highly complex. My goals were to 1) determine whether specific individuals in this population led group travel more often than expected; 2) determine whether certain factors predicted which animals would lead most often and 3) investigate the benefits of leading to leaders and to followers in a fission-fusion society. Multiple types of data were collected to answer questions posed including dolphin behavior (for leadership analyses), fish sampling (to examine dolphin habitat use under leadership), and dolphin biopsy sampling (for genetic analyses). Results of analyses provided strong evidence for consistent leadership in this population. Leaders were female, most were mothers and on average they had larger measures of centrality within the LFK population. Leaders benefited by leading individuals who were more closely related than expected. Followers benefited from efficient access to profitable habitat. Results build on previous leadership research by expanding our knowledge about the type of species in which specific individuals lead and predictors for what types of individuals may lead. Additionally, results provide the first detailed information about benefits group members obtain by both leading and following.
5

Feeding and reproductive strategies of ranging behavior in male Japanese macaques / ニホンザルオス個体の遊動行動: 採食・繁殖戦略上の意義

Otani, Yosuke 23 July 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18498号 / 理博第4013号 / 新制||理||1578(附属図書館) / 31384 / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 半谷 吾郎, 教授 湯本 貴和, 教授 高田 昌彦 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
6

Fission fusion dynamics of olive baboons (Papio anubis) in Gashaka-Gumti National Park

Alberts, Nienke January 2013 (has links)
Primate societies have been classified into discrete categories based on the flexibility of their social organisation. However, due to growing evidence of intra-specific and temporal variation in grouping patterns, it has been suggested that instead, primate societies should be characterised by their relative degree of fission-fusion dynamics, which indicates the extent to which groups vary in spatial cohesion and the temporal variation in the size and composition of parties. While perceived predation risk and food availability are known to be key factors shaping primate societies, it is not clear if fission-fusion dynamics reflect short-term behavioural adaptations to these factors, and if social preferences also influence fission-fusion dynamics. Furthermore, little is known about the impact of fission-fusion dynamics on social relationships. These issues are addressed in this thesis by investigating the grouping patterns and social relationships of two troops (Gamgam and Kwano) of free-ranging olive baboons (Papio& hamadryas & anubis) in Gashaka-Gumti National Park, Nigeria. Grouping patterns were measured through association networks and the temporal variation in party size, party composition, and spatial cohesion, and were related to variations in food availability, predation risk, and habitat use. Variations in patterns of associations and fission-fusion dynamics were found both between troops, and between seasons within troops. As these variations could largely be accounted for by differences in ecology and demography, it seems that fission-fusion dynamics reflect a short-term optimisation of the trade-off between the cost and benefits of group living. The network of associations of the fluid Kwano troop, but not of the cohesive Gamgam troop, was found to be sub-structured in a way that indicates Infanticide avoidance may play an important role in association patterns. Both the frequencies of social behaviours, and the structures of networks based on five types of social interactions, were related to differences in fission-fusion dynamics. The degree of fission-fusion dynamics appears to influence social relationships, as a quantitative difference in social behaviour was linked to variation in fission-fusion dynamics.
7

Female gregariousness and social bonding in the male-philopatric society of bonobos (Pan paniscus) / ボノボの父系社会におけるメスの凝集性と親和関係

Tokuyama, Nahoko 25 July 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19920号 / 理博第4220号 / 新制||理||1606(附属図書館) / 33006 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 古市 剛史, 教授 湯本 貴和, 教授 平井 啓久 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
8

Day-roosting Social Ecology of the Northern Long-eared Bat (Myotis septentrionalis) and the Endangered Indiana Bat (Myotis sodalis)

Silvis, Alexander 08 December 2014 (has links)
Day-roost use by northern long-eared bat (Myotis septentrionalis) maternity colonies on the Fort Knox military reservation, Kentucky, USA, resulted in formation of non-random networks of roosts that exhibited a trend toward centralization. Centralization of day-roost networks was reflected in the social structure of colonies, which were characterized by dense associations among individuals within colonies. Social structure varied among colonies and appeared to be related to reproductive condition; colonies exhibited greater cohesiveness during parturition and lactation. Northern long-eared bat maternity colonies appeared to be exclusive, occupying distinct roosting areas with one or several areas receiving intense use. Day-roost removal simulations suggested a linear relationship between colony fragmentation and roost loss, and that loss of >20% of roosts is required to initiate colony fragmentation. Experimental hierarchical removal of day-roosts yielded results consistent with simulations, as removal of the single most-central (primary) roost had no impact on colony fragmentation, whereas removal of 24% of less-central (secondary) roosts resulted in partial network fragmentation. Patterns of colony day-roost and space use were similar pre- and post-removal treatments. Day-roost removal did not alter the number of roosts used by individual bats, but distances moved between roosts were greater in the secondary roost-removal treatment group. Day-roost characteristics largely were consistent pre-post treatment for both treatment groups. Historical data from an Indiana bat (Myotis sodalis) maternity colony revealed that this species also exhibits a non-random social assorting dynamic. Non-random social assortment resulted in a closely connected centralized network of day-roosts. Individuals within the Indiana bat maternity colony exhibited close social connections with colony members, but subgroups likely existed within the colony. Indiana bat day-roosting ecology appears flexible, as patterns of roost and space use differed substantially between years. Development of specific, but tactical, management approaches for individual colonies of both northern long-eared and Indiana bats may be possible. Such approaches would allow land managers to manage for both northern long-eared bat habitat and other objectives. However, the nature of targeted management approaches employed likely will depend on the unique forest context and dynamic within which individual colonies reside. / Ph. D.
9

Nuclear Dissipative Dynamics In Langevin Approach

Tanriverdi, Vedat 01 June 2004 (has links) (PDF)
In this thesis Langevin approach is applied to analyze the nuclear dissipative dynamics in fission and fusion reactions. In these investigations, the nuclear elongation coordinate and the corresponding momentum are chosen as collective variables. By considering changes in these variables the decay rate of fission and the formation probability of fusion for heavy ion reactions are calculated. These calculations are performed using simulation techniques and the results thus obtained are compared with the corresponding results of analytic solutions.
10

Comportamento social de botos-cinza, sotalia guianensis, na praia de Pipa, RN, Brasil: din?mica, sequ?ncia, sincronia e respostas ao turismo de observa??o

Lunarde, Diana Gon?alves 31 March 2011 (has links)
Made available in DSpace on 2014-12-17T15:37:03Z (GMT). No. of bitstreams: 1 DianaGL_TESE_1-60.pdf: 3945578 bytes, checksum: b60b2a1d9ab72539c6bd59f14847deca (MD5) Previous issue date: 2011-03-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Social behavior of Guiana dolphins, Sotalia guianensis, at Pipa Beach, RN, Brazil: dynamics, sequence, breathing synchrony, and responses to dolphin watching. Social animals form groups that can range from temporary to permanent. Depending on the nature of the social relationships developed between individuals, groups present a particular social organization and the effect of these interactions shapes the activity patterns of these animals. This study investigates: (i) fission-fusion dynamics of Guiana dolphins, through the analysis of three dimensions of the social system (variation in spatial cohesion, variation in size and composition of groups), (ii) sequence, routine and behavioral stability, (iii) breathing intervals in synchronized groups and (iv) behavioral responses of the animals to dolphin watching. Systematic observations of Guiana dolphins were made from a platform located in cliffs about 25 m above sea level that surround Madeiro Bay, Pipa Beach. Sampling occurred from December 2007 to February 2009 between 0600 h and 1600 h, and the groups of Guiana dolphins were investigated according to their size (alone and group) and composition (adults, adults and juveniles, and adults and calves). According to the analysis of fission-fusion dynamics, Guiana dolphin groups frequently changed their composition, modifying their patterns of spatial grouping and cohesion every 20 minutes on average. More than 50% of the individuals maintained a distance of up to 2 m from other group members and new individuals were attracted to the group, especially during feeding, leaving it for foraging. Large groups were more unstable than small, while groups containing only adults were more stable than groups of adults and juveniles. According to the Z-score analysis to investigate the sequence and behavioral routine, lone individuals were more ! .7! ! involved in foraging and feeding, while resting was more common in groups. Foraging and feeding were more common in homogeneous groups (individuals of the same age class), while heterogeneous groups (different age classes) were often involved in socialization, displaying a broader behavioral repertoire. Foraging and resting behavior presented higher stability (continuous duration in minutes) than the other behaviors. The analysis of breathing intervals in synchronized groups showed significant differences depending on type of behavior, composition and area preference. During resting, breathing intervals were of longer duration, and groups with calves showed shorter breathing intervals than groups without calves. Lone individuals also preferred areas called corral , often used for the entrapment of fishes. The Markov chain analysis revealed behavioral changes in the presence of boats, according to the type of group composition. Groups composed of adults presented decreased resting and increased in traveling during the presence of boats. Groups of adults and juveniles showed a massive reduction of socialization, while the behavior transition probability traveling-traveling was higher in groups of adults and calves. In the presence of the boats, stability of resting was reduced by one third of its original duration and traveling more than doubled. The behavioral patterns analyzed are discussed in light of socio-ecological models concerning costs and benefits of proximity between individuals and behavioral optimization. Furthermore, significant changes in behavioral patterns indicate that Guiana dolphins, at Pipa Beach, have suffered the effects of tourism as a result of violation of rules of conduct established for the study area / Animais sociais formam grupos que podem variar de tempor?rios a permanentes. Dependendo da natureza das rela??es sociais que se desenvolvem entre os indiv?duos, grupos apresentam uma organiza??o social particular e o resultado destas intera??es moldar?o o padr?o comportamental desses animais. O presente estudo visa investigar: (i) a din?mica de fiss?o-fus?o de botos-cinza, por meio da an?lise de tr?s dimens?es do sistema social (varia??o na coes?o espacial, varia??o no tamanho e na composi??o dos grupos); (ii) a sequ?ncia, rotina e estabilidade comportamental; (iii) os intervalos respirat?rios em grupos sincr?nicos e (iv) as respostas comportamentais ao turismo de observa??o. Observa??es sistem?ticas de botos-cinza foram feitas a partir de um mirante localizado na enseada do Madeiro, praia de Pipa, a aproximadamente 25 m acima do n?vel do mar. As amostragens ocorreram entre dezembro de 2007 e fevereiro de 2009, entre 0600 h e 1600 h e os grupos de boto-cinza foram investigados de acordo com seu tamanho (sozinho e em grupo) e composi??o (adultos, adultos e juvenis, e adultos e filhotes). De acordo com a an?lise de din?mica de fiss?o-fus?o, botos-cinza mudaram sua composi??o frequentemente, modificando o tamanho dos grupos, em m?dia, a cada 20 min. Mais de 50% dos indiv?duos mantiveram dist?ncias de at? 2 m entre si e novos indiv?duos foram atra?dos ao grupo, principalmente durante alimenta??o, deixando-o durante o forrageio. Grandes grupos mostraram-se mais inst?veis do que pequenos grupos, enquanto grupos de adultos foram mais est?veis do que grupos de adultos e juvenis. De acordo com a an?lise de Z-score para investiga??o da sequ?ncia e rotina comportamental, indiv?duos sozinhos estiveram mais envolvidos em comportamentos de forrageio e alimenta??o, enquanto o repouso foi mais comum em indiv?duos em grupo. O forrageio e a alimenta??o foram mais comuns em grupos homog?neos (indiv?duos de mesma classe et?ria), enquanto grupos heterog?neos (de diferentes ! 5! ! classes et?rias) estiveram frequentemente envolvidos em socializa??o, apresentando um repert?rio comportamental mais amplo. Os comportamentos de repouso e forrageio apresentaram maior estabilidade (dura??o cont?nua em minutos), do que os demais comportamentos. A an?lise de intervalos respirat?rios em grupos sincr?nicos apontou diferen?as significativas quanto ao tipo de comportamento, composi??o e prefer?ncia de ?rea. Durante o comportamento de repouso foram observados os intervalos respirat?rios de maior dura??o, e grupos com filhotes apresentaram menores intervalos do que grupos sem filhotes. Indiv?duos sozinhos preferiram ?reas denominadas de curral , frequentemente utilizadas para o encurralamento de peixes. A partir da an?lise de cadeia de Markov, foram detectadas diferentes altera??es comportamentais na presen?a dos barcos, de acordo com o tipo de composi??o do grupo. Grupos de adultos sofreram a maior redu??o do repouso e o maior aumento do deslocamento. Adultos e juvenis apresentaram maior redu??o da socializa??o, enquanto a probabilidade de transi??o comportamental deslocamento-deslocamento foi maior em grupos de adultos e filhotes. Na presen?a dos barcos a estabilidade do repouso foi reduzida em um ter?o de sua dura??o original e o deslocamento aumentou mais do que o dobro em todas as composi??es de grupo. Os padr?es comportamentais analisados s?o discutidos ? luz dos modelos socioecol?gicos sobre custos e benef?cios da proximidade entre indiv?duos e otimiza??o comportamental. Ademais, mudan?as significativas no padr?o comportamental indicam que os botos-cinza, na praia de Pipa, v?m sofrendo os efeitos do turismo, como consequ?ncia da viola??o das normas de conduta estabelecidas para a ?rea de estudo

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