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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

The superfluid properties of a Bose-Einstein condensed gas

Hodby, Eleanor January 2002 (has links)
No description available.
2

Laser cooling and trapping of atoms

Cooper, Catherine J. January 1995 (has links)
No description available.
3

Light-trap studies of seasonal and geographical occurrence of certain species of Lepidoptera in Kansas

Payne, Julius James January 2011 (has links)
Digitized by Kansas State University Libraries
4

Factors affecting escalation in auction games

Jones, Gareth G. January 1986 (has links)
Auction games have been relatively neglected by empirical researchers in spite of their apparent relevance to a wide range of social problems. Following a discussion of social dilemmas in general, and an exhaustive review of research into psychological traps and auction games in particular, six new experiments on factors affecting escalation in auction games are reported. In the first experiment, male and female subjects participated in three successive auction games with variable prize values. A serial decrease in escalation with experience was observed among males only; no significant effect of prize value was found. Experiment two compared subjects' responses to programmed strategies in two-person and three-person groups, either face-to-face or via a computer simulation designed to provide greater control and to facilitate economical data-collection. A significant interaction emerged: escalation was significantly greater in the computer simulation than the face-to-face condition in the two-person groups only. The successful computer simulation was retained for all subsequent experiments, and experiment three examined the relationship between escalation and personality. A significant positive relationship was found between radicalism and escalation. In the fourth experiment no significant differences were found between individual and team bidding (in teams of two or three), but in the fifth experiment a non-significant trend towards greater escalation in individual than in three-person team bidding was observed. The sex difference, and the interaction reported by previous researchers between sex and individual versus team bidding, were non-significant, although there was a trend towards greater escalation by individuals than teams. Experiment six compared individual bidding in two-person, three-person, and five-person groups. Escalation was found to be significantly greater in the three-person and five-person groups than in the two-person groups. Methodological difficulties and problems of interpretation in all six experiments are discussed and areas in need of further investigation are suggested.
5

The development of a computational methodology for the prediction of the sediment retention performance of invert traps in combined sewer systems

Buxton, Adrian Paul January 2002 (has links)
No description available.
6

Ecological importance of carnivory in the genus Utricularia

Jobson, Richard W., University of Western Sydney, Hawkesbury, Faculty of Science and Technology, School of Science January 1998 (has links)
Three species of the carnivorous bladderwort Utricularia (U. uliginosa, U. uniflora and U. gibba) were studied in the field to determine the fauna content or prey, within their bladder-traps. The immediate soil/water environment was also sampled to determine the fauna present, in order to enable comparison between the prey fauna and the surrounding fauna. Comparison of the trap fauna with the soil/water fauna revealed evidence of selectivity in trapping: the trap fauna were not simply a random sample of the soil/water fauna. A glasshouse experiment was designed to determine whether the terrestrial bladderwort species U. uliginosa gained any growth advantage from carnivory. Three organism treatments were factorially combined with three Nitrogen levels. The advantage to plants of trapping meiofauna was apparent at the two lower N-levels, but not at the highest N-level. The nitrogen treatments did not confer any significant advantage on plant growth for leaf and trap numbers or stolon length. Nitrogen level did however have a significant effect on leaf area at harvest 2, with plants in the middle nitrogen level having more leaf area than plants in the lower and higher nitrogen levels / Master of Science (Hons)
7

Evaluation of a common carp (Cyprinus carpio L.) exclusion and trapping device for use in aquatic plant founder colony establishment

Williams, Paul Edwin. Hudak, Paul F., January 2008 (has links)
Thesis (M.S.)--University of North Texas, May, 2008. / Title from title page display. Includes bibliographical references.
8

Observations on the operation of two light traps at Manhattan during two seasons and an analysis of the catch of twenty-five species of Lepidoptera

Nonamaker, Harold Leroy January 1933 (has links)
Typescript, etc.
9

Predação de ninhos artificiais nas diferentes paisagens do bioma mata atlântica, no estado de São Paulo

Galvão, Camila André 18 March 2015 (has links)
Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-13T13:11:33Z No. of bitstreams: 1 DissCAG.pdf: 1588922 bytes, checksum: a5934cedb789c0456c3051fcde155acb (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-13T20:29:41Z (GMT) No. of bitstreams: 1 DissCAG.pdf: 1588922 bytes, checksum: a5934cedb789c0456c3051fcde155acb (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-13T20:29:51Z (GMT) No. of bitstreams: 1 DissCAG.pdf: 1588922 bytes, checksum: a5934cedb789c0456c3051fcde155acb (MD5) / Made available in DSpace on 2016-09-13T20:30:12Z (GMT). No. of bitstreams: 1 DissCAG.pdf: 1588922 bytes, checksum: a5934cedb789c0456c3051fcde155acb (MD5) Previous issue date: 2015-03-18 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The nest predation is an event that adversely affects the reproductive success of birds. One of the main theories explaining their population decline is the "Theory mesopredator release", especially in fragmented areas, where the chain of top predators are the first to go extinct, causing an increase in mesopredators in place, leading to an growth in nest predation and reduction of the bird population. In this context, estimate the nest predation, through the use of artificial nests is of paramount importance both in preserved areas, as fragmented, present in the vicinity of protected areas in order to know which are the natural predators of nests, estimates predation intensity, quickly, in different landscapes present in the Atlantic Forest biome. Thus, the artificial nests was sampled through the use of nests (artificial), each containing two nest eggs of domestic fowl Quail (Coturnix cotunix), and camera traps. In all study areas the cameras and the nests were placed together in the field (both at the top, as on the ground), so that predation records were provided by recording 30-second videos filmed by the cameras. In Carlos Botelho State Park (CBSP) gave a sampling effort 2100 cameras/night. It’s surrounding area analyzed, corresponding to the Agroforestry System (AS) provided 7200 cameras/hours sampling. As for the territorial portion of the Capão Bonito National Forest (NF) and its surroundings were sampled together, making an effort 1155 cameras/night. Several species of birds (10), reptiles (1) and mammals (7) were recorded preying on the eggs, accounting for an overall predation rate, for all fields of study, 42.6%. The CBSP obtained a 28.6% predation rate, corresponding to the rates in other areas as well preserved. Not so for NF he presented such a high rate (45.8%) as found in disturbed environments analyzed, AS and surrounding National Forest (100% and 65.5%, respectively). Among birds, the main predators were “Arapaçu de bico preto” (Dendrocolaptes platyrostris), “Falcão Relógio” (Micrastur semitorquatus) and “Macuco” (Tinamus solitarius), in Carlos Botelho State Park. In NF, the “Gralha-decrista- negra” (Cyanocorax chrysops), stood out as the main predator bird, and the “Gralha-Azul” (Cyanocorax caeruleus) for the AS. Among mammals, the CBSP the “Cuíca-de-quatro-olhos” (Philander frenatus) and the “Irara” (Eira barbara) were the most prominent. In NF, the "Javaporco" (Sus sp) became the dominant predator. In AS, the “Gambá-de-orelha-preta” (Didelphis aurita) was the only mammal predator. And for the group of reptiles, only the “Teiú” (Tupinambis merinae) did prey the nest in Carlos Botelho. In addition, depredations on the ground were the most abundant in all areas of study, corresponding 65% of predation compared to 35% of depredations on top, and during the daytime, corresponding to 77%. Thus, we can conclude that nests on the ground, depredations during the day, for bird species, corresponds to the profile of nest predators in the Atlantic Forest in the State of São Paulo. Nevertheless, the NF proved to be very close in terms of species composition and predation rate your anthropic environment. And the alternative of sustainable production, AS, resembled much of the damage also caused by conventional production of agricultural products (NF surroundings), in this case, the fauna of birds present in the Atlantic Forest. / A predação de ninhos é um evento que afeta negativamente o sucesso reprodutivo das aves. Uma das principais teorias que explicam seu declínio populacional é a “Teoria de Liberação de Mesopredadores”, principalmente em áreas fragmentadas, onde os predadores de topo de cadeia são os primeiros a se extinguirem, causando um aumento dos mesopredadores no local, levando a um crescimento na predação de ninhos e na redução da população de aves. Neste contexto, estimar a predação de ninhos, através do uso de ninhos artificiais é de suma importância, tanto em áreas preservadas, como fragmentadas presentes no entorno de Unidades de Conservação, a fim de conhecer quais são os predadores naturais de ninhos, as estimativas de intensidade de predação, de maneira rápida, nas diferentes paisagens presentes no Bioma Mata Atlântica. Desse modo, a predação de ninhos artificiais foi amostrada por meio do uso de ninhos (artificiais), contendo cada ninho dois ovos da ave doméstica Codorna (Coturnix cotunix), e armadilhas fotográficas (Câmeras traps). Em todas as áreas de estudo as câmeras e os ninhos foram dispostos juntos no campo (tanto no alto, como no chão), a fim de que registros de predações fossem proporcionados pela gravação de vídeos de 30 segundos filmados pelas câmeras. No Parque Estadual Carlos Botelho (PECB) obteve-se um esforço amostral de 2100 câmeras/noite. Sua área de entorno analisada, correspondendo ao Sistema Agroflorestal (SAF) proporcionou 7200 horas/câmera de amostragem. Já para a porção territorial da Floresta Nacional (FLONA) de Capão Bonito e seu entorno foram amostradas juntas, perfazendo um esforço de 1155 câmeras/noite. Diversas espécies de aves (10), répteis (1) e mamíferos (7) foram registradas predando os ovos, contabilizando uma taxa de predação geral, para todas as áreas de estudo, de 42,6%. O PECB obteve uma taxa de predação de 28,6%, correspondendo ás taxas em outras áreas também preservadas. O mesmo não aconteceu para a FLONA em que apresentou uma taxa tão alta (45,8%) quanto a encontrada nos ambientes perturbados analisados, SAF e entorno FLONA (100% e 65,5%, respectivamente). Entre as aves, os principais predadores foram: Arapaçu de bico preto (Dendrocolaptes platyrostris), Falcão Relógio (Micrastur semitorquatus) e Macuco (Tinamus solitarius), no Parque Estadual Carlos Botelho. Na FLONA, a Gralha-decrista- negra (Cyanocorax chrysops), destacou-se como principal ave predadora, assim como a Gralha azul (Cyanocorax caeruleus) para o SAF. Entre os mamíferos, no PECB a Cuíca de quatro olhos (Philander frenatus) e a Irara (Eira barbara) foram os de maior destaque. Na FLONA, o “Javaporco” (Sus sp) tornou-se o predador dominante. No SAF, o Gambá de orelha preta (Didelphis aurita), foi o único predador mamífero. E para o grupo dos répteis, somente o Teiú (Tupinambis merinae) predou o ninho, em Carlos Botelho. Além disso, predações no chão foram as mais abundantes em todas as áreas de estudo, correspondendo 65% das predações em relação a 35% de predações no alto, e durante o período diurno, correspondendo a 77%. Desse modo, pode-se concluir que ninhos no chão, predações durante o dia, por espécies de aves, corresponde ao perfil de predadores de ninhos na Mata Atlântica no Estado de São Paulo. Não obstante, a FLONA mostrou-se muito próxima a nível de composição de espécies e taxa de predação a seu entorno antropizado. E, a alternativa de produção sustentável, o SAF, se assemelhou muito aos prejuízos também causados pela produção convencional de produtos agrícolas (entorno FLONA), no caso, à fauna de aves presentes na Mata Atlântica.
10

Evaluating shade bias in insect trap catch and assessing the short- and long-term impacts of herbicide application in regenerating clearcuts on flowering plant communities /

Georgitis, Kathryn M., January 2001 (has links)
Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 74-77).

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