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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.
71

The effect of interaction on preferences in white Peking ducklings (Anas patyrhynchos)

Germain, Sarah M. 06 April 2011 (has links)
The purpose of the current set of experiments was to investigate the interaction component of avian attachment behaviour. The latter is viewed as the outcome of several components, all of which potentially interact with each other. In these experiments, the visual, brood size, animate vs. inanimate, and familiarity components of avian attachment behaviour were held constant so that the effects of interaction were evaluated unambiguously. The results for Time 1 (T1) yielded various results for both Condition A (Interaction with the other species/breed) and B (Interaction with same species/breed). For T2 (Condition A), the four Experiments yielded various results. For T2 (Condition B), the four Experiments yielded consistent results. When experimental subjects interacted with their own species/breed (white Peking duckling), the preference for their own species/breed (white Peking ducklings) increased while the preference for the other species/breed (domestic chicks or mallard ducklings) decreased. In Experiment 3 and Experiment 4, there was a complete reversal of preference from T1 to T2.
72

Application of multiplex branched DNA method for the detection and study of avian inlfuenza [i.e. influenza] virus

Cha, Wonhee, January 2008 (has links)
Thesis (M. S.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 89-103).
73

Development and evaluation of DNA vaccines in chickens against a wild bird H6N2 avian influenza virus from Western Australia /

Shan, Songhua. January 2009 (has links)
Thesis (Ph.D.)--Murdoch University, 2009. / Thesis submitted to the Faculty of Health Sciences. Includes bibliographical references (p. 275-332)
74

Mechanisms of pathogenic avian influenza-induced immune responses in human cells

Mok, Ka-pun, Chris. January 2004 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
75

Influenza A virus replication and cytokine responses in murine macrophages in vitro

Chan, Wan-yi. January 2005 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
76

The framing of China's bird flu epedemic by U.S. newspapers influencial [sic] in China how the New York Times and the Washington Post linked the image of the nation to the handling of the disease /

Song, Ning. January 2007 (has links)
Thesis (M.A.)--Georgia State University, 2007. / Title from file title page. Arla G. Bernstein, committee chair; Holley Wilkin, Leonard Teel, committee members. Electronic text (92 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Oct. 17, 2007. Includes bibliographical references (p. 83-92).
77

Unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins

Van Doorslaer, Koenraad, Ruoppolo, Valeria, Schmidt, Annie, Lescroël, Amelie, Jongsomjit, Dennis, Elrod, Megan, Kraberger, Simona, Stainton, Daisy, Dugger, Katie M, Ballard, Grant, Ainley, David G, Varsani, Arvind 07 1900 (has links)
The family Papillomaviridae contains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. To date, only nine non-mammalian papillomaviruses have been described from birds (n = 5), a fish (n = 1), a snake (n = 1), and turtles (n = 2). The identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest Euteleostomi. The Euteleostomi clade includes more than 90 per cent of the living vertebrate species, and progeny virus could have been passed on to all members of this clade, inhabiting virtually every habitat on the planet. As part of this study, we isolated a novel papillomavirus from a 16-year-old female Adelie penguin (Pygoscelis adeliae) from Cape Crozier, Ross Island (Antarctica). The new papillomavirus shares similar to 64 per cent genome-wide identity to a previously described Adelie penguin papillomavirus. Phylogenetic analyses show that the non-mammalian viruses (expect the python, Morelia spilota, associated papillomavirus) cluster near the base of the papillomavirus evolutionary tree. A papillomavirus isolated from an avian host (Northern fulmar; Fulmarus glacialis), like the two turtle papillomaviruses, lacks a putative E9 protein that is found in all other avian papillomaviruses. Furthermore, the Northern fulmar papillomavirus has an E7 more similar to the mammalian viruses than the other avian papillomaviruses. Typical E6 proteins of mammalian papillomaviruses have two Zinc finger motifs, whereas the sauropsid papillomaviruses only have one such motif. Furthermore, this motif is absent in the fish papillomavirus. Thus, it is highly likely that the most recent common ancestor of the mammalian and sauropsid papillomaviruses had a single motif E6. It appears that a motif duplication resulted in mammalian papillomaviruses having a double Zinc finger motif in E6. We estimated the divergence time between Northern fulmar-associated papillomavirus and the other Sauropsid papillomaviruses be to around 250 million years ago, during the Paleozoic-Mesozoic transition and our analysis dates the root of the papillomavirus tree between 400 and 600 million years ago. Our analysis shows evidence for niche adaptation and that these non-mammalian viruses have highly divergent E6 and E7 proteins, providing insights into the evolution of the early viral (onco-)proteins.
78

Determinación de infección contra Avian avulavirus 19 en pingüinos del territorio antártico chileno durante el año 2017

Olivares Becerra, Florencia Ignacia January 2018 (has links)
Memoria para optar al Título Profesional de Médico Veterinario / El Avian avulavirus 19 (APMV) es un paramixovirus descubierto y aislado en 2017 desde pingüinos de Papúa (Pygoscelis papua) en la Isla Kopaitic del Territorio Antártico Chileno. En esta investigación se realizó la técnica de inhibición de la hemaglutinación (HI) para medir la presencia de anticuerpos específicos para este virus en las tres especies de pingüinos Pygoscelis spp. Los sueros se obtuvieron desde 7 localidades; Cabo Shirreff, Isla Doumer, Punta Biscoe, Bahía Paraíso, Isla Lagotelerie, Isla Ardley e Isla Avian. De un total de 496 muestras procesadas solo 45 resultaron positivas (9%). Se obtuvo evidencia del virus en las tres especies estudiadas, para los pingüinos de Adelia (P. adeliae) 1/80 (1,25%); en el caso de los de barbijo (P. antarctica) 30/206 (14,6%); y por último los Papúa 14/210 (6,7%). En cuanto a los sitios estudiados, 4/7 resultaron positivos (Cabo Shirreff, Doumer, Punta Biscoe y Bahía Paraíso). Del total de sitios muestreados, se identificaron tres grupos con diferentes niveles de anticuerpos, lo cual fue estadísticamente significativo como alto, medio y negativo. En los sitios donde se obtuvo un número reducido de muestras, se realizó una estimación de la prevalencia: Punta Biscoe ≥20%; Isla Doumer ≥ 14,5% y en Bahía Paraíso ≥17%. Por otro lado, en Cabo Shirref, donde se obtuvo una mayor cantidad de muestras de barbijo, se obtuvo una prevalencia verdadera de 14,6%. En la Isla Ardley, Isla Lagotelerie e Isla Avian no se encontró evidencia de infección. En cuanto a los posibles medios de transmisión de este nuevo virus, se describe a las aves acuáticas migratorias como importantes diseminadores en el ambiente. De éstas, las más relevantes serían los salteadores (Stercorarius spp.), que depredan pingüinos y que están en contacto directo con éstos. En el caso del virus de Newcastle (NDV), las personas son su principal riesgo de transmisión. Mucho queda por descifrar en cuanto a su forma de transmisión. En conclusión, la hipótesis resultó ser verdadera debido a que se encontró evidencia de infección en las tres especies estudiadas. Esta investigación crea nuevas interrogantes, sería interesante descifrar la temperatura mínima a la que AVA 19 permanece infectivo, quizás las bajas temperaturas beneficien a este virus envuelto. Este es el primer trabajo donde se investiga la seroprevalencia de Avian avulavirus 19, futuros trabajos son necesarios para entender mejor la dinámica infecciosa de estos nuevos agentes. / The Avian avulavirus 19 (APMV) is a paramyxovirus discovered and isolated in 2017 from Gentoo penguins (Pygoscelis papua) sampled in Kopaitic island, Chilean Antarctic territory. Hemagglutination inhibition (HI) assay were performed in order to measure the presence of specific antibodies for this virus in three species of Pygoscelis spp. The sera were obtained from 7 locations; Cape Shirreff, Doumer Island, Biscoe Point, Paradise Bay, Lagotelerie Island, Ardley Island and Avian Island. A total of 496 samples were tested, 45 (9%) were positive. Evidence of the virus infection was found on all three species. In the case of Adelie penguins (P. adeliae) 1 out of 80 (1.25%) were positive; for the Chinstrap penguins (P. antarctica) 30 out of 206 (14.6%); and finally, for the Gentoo penguins 14 out of 210 (6.7%) were positive. Overall results indicated that 4 locations were positive (Cape Shirreff, Doumer Island, Biscoe Point and Paradise Bay). From these sites, three groups with different antibody concentrations (high, medium and no antibodies) where identified, this was statistically significant. In the places where a few amounts of sera were obtained, it could only be performed an estimation of the prevalence. In Biscoe Point it’s ≥ 20%; ≥ 14.5% for Doumer Island and ≥ 17% in Paradise Bay. On the other hand, in Cape Shirreff, where a bigger amount of sera where sampled in Chinstrap penguins, a true prevalence of 14.6% were obtained. In the Ardley, Lagotelerie and Avian Islands no evidence of infection were found. As for the possible means of transmission of this new virus, it’s described in the literature that migratory waterfowl are important environment propagators of paramyxoviruses. The most relevant ones are skuas (Stercorarius spp.), which predate on penguins and are in direct contact with them. In the case of NDV people are the mains transmission risk. A lot remains unknown as for this virus transmission. In conclusion, the hypothesis proved positive because serological evidence was found on all three species. This research brings new questions. It would be interesting to figure out the minimum temperature in which AVA 19 remains infective, it may be possible that low temperatures benefit this enveloped virus. This is the first work where the seroprevalence of Avian avulavirus 19 is researched. Future works are needed to understand the infectious dynamics of these new agents. / Proyecto INACH 46-16
79

Effect of Ribavirin on Phenotypic Reversion of Mammalian cells Transformed by Temperature-Sensitive Mutants of Avian Sarcoma Virus

Siripont, Janya 12 1900 (has links)
The effect of ribavarin (1-β-D-ribofuranosyl-1,2,4-triazole-3-carboxamide), a synthetic nucleoside, on a series of cellular properties which characterize the transformed state was studied using normal rat kidney cells (NRK) and cloned derivatives transformed by a wild type avian sarcoma virus, B77-NRK, and by a temperature-sensitive mutant of the virus, LA31-NRK.
80

Effects Of Patch Size And Matrix Type On Bird Assemblages Within Central Florida Cypress Domes

Noran, Julia 01 January 2006 (has links)
The numerous studies on the effects of patch size on bird assemblages have produced varied results. I studied the effects of patch size and surrounding matrix on bird assemblages within central Florida cypress domes. My null hypothesis was that bird assemblages within cypress domes are unaffected by dome size or development in the matrix around the dome. My alternative hypothesis was that differences in bird assemblages are correlated with size and the degree of development within the matrix. I classified a pool of over a thousand domes according to three size categories and four matrix types. Three representatives for each combination of size and matrix were spot mapped for birds from May through August 2005. I examined the relationship of species richness and bird guilds to patch size and surrounding matrix. I also measured a series of potential covariates for each dome to account for variation among the three size-matrix representatives for each combination. Richness and abundance counts were divided by the number of listening points to standardize the data by effort. I found that the standardized species richness of bird assemblages significantly increased with the patch size of cypress domes; however, matrix and the interaction effect of size and matrix on overall standardized species richness were not significant. Significant covariates included percent of the buffer undeveloped, percent herbaceous cover, and the number of listening points per unit area. A linear regression tested for significant effects of log area and matrix on standardized species richness. Matrix was not significant, but log area did have a significant effect on standardized species richness. The MANOVA tests for guild richness data indicated no significant effects of dome size, matrix, or their interaction effect on diet, foraging, or location guilds. There were no significant main or interaction effects on any individual guilds in the ANOVA output. Individual backward linear regressions done on each guild indicated that matrix did not have significant effects on any guild, but log area had significant effects on ground foragers, lower-canopy foragers, omnivores, herbivores, and edge species. I then investigated the effects of size and matrix on standardized guild abundance. Dome size and matrix significantly effected diet guild abundance, but the size-matrix interaction did not. Dome size significantly affected insectivores, omnivores, and carnivores. Matrix had a significant effect on omnivores, herbivores, and carnivores. The size and matrix interaction had a significant effect on carnivores. Dome size and matrix significantly affected foraging guild abundance, but the size-matrix interaction did not. Dome size significantly affected ground, lower- and upper-canopy foragers. Matrix had a significant effect on ground, water, and upper-canopy foragers. The size and matrix interaction was not significant for any foraging guild. Dome size and matrix significantly effected location guild abundance, but the size-matrix interaction did not. Dome size significantly affected edge and interior species. Matrix had a significant effect on edge and interior species. The size and matrix interaction was not significant for any location guild. The relationship between species richness and habitat area is well-documented, and the results of this study were consistent with the expectation of higher species richness in larger areas. If maintaining high species richness is the sole goal of conservationists, then large habitat fragments would be preferable regardless of surrounding matrix. Nevertheless, species richness alone is not informative of the potential effects of patch size and matrix on the composition of an avian assemblage. Guild analysis gives insight into community structure and should be considered in addition to simple measures of species richness. Patch size and matrix type significantly affected a number of guilds, and several factors could contribute to the observed differences in guilds across patch size categories and matrix types. Different habitats are available to birds in domes of each size class and matrix type. The potential for diverse foraging opportunities increases as domes increase in size and change in relation to their surrounding matrix. A more detailed analysis is needed to determine how differences in vegetation of domes and surrounding matrix affect guilds, members of which may use habitats both within domes and the matrix. Cypress domes in the central Florida area face severe alteration or destruction due to rapid development. Long-term research that focuses on domes before and after development is needed to understand how changes in the matrix or size of the domes affect all resident flora and fauna. A variety of taxa and biogeochemical processes should be researched. Domes are naturally highly variable in size, shape, and structure, and development changes all of these characteristics. Conservation biologists and managers urgently need to determine how development affects cypress domes and what can be done to maintain their characteristic biodiversity.

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