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1
Barch, Brian T. "The annual midwest crane count : development of a program plan /." Link to full-text, 2006. http://epapers.uwsp.edu/thesis/2006/barch.pdf.
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2
Bulin, Brad A. "Avian diversity in relation to lakeshore development in Portage County, Wisconsin /." Link to abstract, 2005. http://epapers.uwsp.edu/abstracts/2005/Bulin.pdf.
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3
Addison, BriAnne Ashley. "Maternally derived antibodies in avian eggs and offspring ecology, life history, and development /." Diss., St. Louis, Mo. : University of Missouri--St. Louis, 2009. http://etd.umsl.edu/r3961.
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4
Maia, Villar de Queiroz Rafael. "The Development and Evolution of Iridescent Colors in Birds." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1407503755.
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5
Russ, Melissa. "An investigation of the effects [of] locust-control pesticides, Fenitrothion and Fipronil, on avian development using an 'in ovo' model." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060712.122711/index.html.
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6
Sirsat, Tushar S. "The Role of Thyroid Hormone across Avian Development Spectrum: Investigations on Systemic Development, Metabolism and Ontogeny of Endothermy." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011746/.
Texte intégralRésumé :
Achievement of endothernic capacity is vital for independence from ambient temperature changes, sustained activity, optimal biochemical reactions and optimization of parental care. During early avian development, the core tenets of transition from ectothermy to endothermy are development of metabolic capacity (oxygen consumption, mitochondrial bioenergetics), enhanced cardiovascular function (heart rate and cardiac output), pulmonary ventilation and thermogenic capacity. Thyroid hormones, particularly T3, are key metabolic regulators of basal metabolism, thermogenesis, pulmonary ventilation and mitochondrial respiration. Thyroid hormone fluctuation patterns during both precocial and altricial avian endothermic transition suggest a prominent role in maturation of endothermy, cardiovascular, respiratory and skeletal muscle physiology. This body of work explores effects of T3 manipulations in two avian species: the precocial Pekin duck and the altricial Red-winged Blackbird. Increased plasma T3 during late incubation resulted in increased cardiac mass, elevated resting and intrinsic heart rate, intrinsic mean arterial pressure, increased cholinergic tone and blunted alpha-adrenergic tone in the precocial Pekin duck. In both Pekin duck and Red-winged blackbird, plasma T3 levels correlated with changes in the trajectory of endothermic ontogeny, systemic oxygen consumption, thermogenesis, maturation of pulmonary ventilatory function, altered growth and effects on skeletal and cardiac mitochondrial bioenergetics. These observations support the role of thyroid hormones as metabolic and developmental regulators at the time of attainment of endothermy during the perinatal period in precocial and altricial avian species. Insights into the role of thyroid hormone as a metabolic and development regulator at the time of avian endothermic attainment provide a more thorough understanding of metabolic and physical transitions a hatchling bird must undergo to reach the adult endothermic phenotype. Such insights also deepen understanding of the complex role thyroid hormones play in homeostasis and offer implications about the evolutionary history of endothermic capacity.
7
Marjoniemi, K. (Kyösti). "Thermogenic mechanisms during the development of endothermy in juvenile birds." Doctoral thesis, University of Oulu, 2001. http://urn.fi/urn:isbn:9514265424.
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Abstract
The use of regulatory and obligatory heat production mechanisms were
studied in
juvenile birds during the development of endothermy.
The development of shivering thermogenesis was studied in the pectoral and
gastrocnemius muscles of the altricial domestic pigeon and in three precocial
galliforms (Japanese quail, grey partridge and domestic fowl). The development of
shivering was the determinant for the beginning of endothermy. Homeothermy also
necessitated avoidance of excess heat loss by insulation and behavioural
thermoregulation. In the precocial species, shivering thermogenesis was present
in the leg muscles of the youngest age groups (1-2 d) studied. Breast muscles
contributed shivering from the second post-hatching week. In the altricial
pigeons, significant thermogenesis was apparent later than in the precocials, at
the age of 6 d. In contrast to the precocials, the pectoral muscles of the
altricials were the most significant heat production tissues. In newly-hatched
partridges and pigeons, incipient shivering did not result in significant heat
production.
The ability to produce heat in cold by putative nonshivering thermogenesis
was
studied in Japanese quail chicks and domestic ducklings. In both species,
three-week cold acclimation resulted in morphometric and physiological changes,
but there was no clear evidence of nonshivering thermogenesis. The lack of NST
was evident because an increase in shivering amplitude at least in one of the
muscles studied paralleled an increase in oxygen consumption. Consequently,
shivering thermogenesis was probably the only mode of regulatory heat
production.
The amplitudes of shivering EMGs measured during cold exposure were
dependent on
the coexistence of postprandial thermogenesis or exercise. Japanese quail chicks
were able to substitute shivering thermogenesis partially with postprandial heat
production when nourished. Bipedal exercise both inhibited shivering in pectorals
directly via inhibitory neural circuits and stimulated it indirectly via
decreased body temperature. Because of increased heat loss, exercise was not used
as a substitute for shivering.
Shivering is a flexible mode of thermogenesis and its magnitude can be
adjusted
according to the magnitude of obligatory thermogenesis. The adjustment works
towards energy saving by avoidance of the summation of different modes of heat
production. The prerequisite for successful adjustment of shivering is adequate
insulation, whose role in preventing excessive heat loss is pronounced during
exercise. It is concluded that the energetics of posthatching thermoregulation
includes the potential for optimizations in energy use in order to avoid
dissipation of waste energy as heat.
8
Serrano, Meneses Martin Alejandro. "Sexual size dimorphism in damselflies, dragonflies and birds : function and development." Thesis, University of Bath, 2006. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434068.
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9
Allen, Vivian Richard. "The evolution of avian hindlimb conformation and locomotor function." Thesis, Royal Veterinary College (University of London), 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559019.
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10
Pearson, James Todd. "A comparative study of the energetics of avian reproduction /." Title page, summary and table of contents only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09php361.pdf.
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11
Johnston, Sonya D. "Development of the pulmonary surfactant system in non-mammalian amniotes /." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phj737.pdf.
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12
Vaughan, Ian P. "Development of species distribution models and their application to birds in river habitats." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55925/.
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1. Distribution models are used as management tools to predict species' distributions and quantify their habitat preferences. Numerous methodological issues require further development, which are explored using the distribution of birds along rivers as a model system in which there is a need to i) develop the quantification and analysis of variation in river habitat features and ii) better quantify species' habitat preferences for conservation and prediction. These themes were linked using a combination of the British Trust for Ornithology's Waterways Breeding Bird Survey (WBBS) and the Environment Agency's River Habitat Survey (RHS), along with similar data from upland Wales and the Himalayan mountains. 2. Training data are the starting point for distribution models and their properties can have profound effects. These issues were investigated via a literature review, which identified key factors including the type of predictors chosen, the approach to environmental sampling and spatial autocorrelation in distribution patterns. Recommendations are made that should optimise model quality, whilst making the most efficient use of available resources. 3. Testing the performance of distribution models is vital. Using a review of the available literature, highlighting weaknesses in current practice, and a case study using a Himalayan river bird, recommendations are made for improved practice. Bootstrapping and independent data should be used to assess overfitting and transportability, respectively. Accuracy statistics should facilitate inter-model comparisons, examining both discrimination and calibration. Nominal presence/absence predictions are problematic: information-theoretic methods may be the most useful approach. 4. Complex habitat data, such as RHS, may create a range of problems during statistical analyses unless the sample size is large. Data reduction, using methods such as principal components analysis (PCA), is an effective solution, but the resulting axes may be difficult to interpret. Using models built with Welsh river bird-RHS data, I compared the interpretability and predictive efficacy of PCA used in its conventional form against PCA preceded by the clustering of RHS variables that referred to the same ecological factors. The two approaches produced similar predictive performance but habitat indices produced by the latter were easier to interpret. A variant of PCA devised for qualitative data was also examined, and benefited RHS analyses involving ordinal variables. 5. Predictive models for 28 river birds, built with the WBBS, represent the first quantitative study linking detailed river habitat data with river bird distributions across the UK. Accuracy varied widely, with better performance for species associated with the river channel, rather than floodplain habitats, reflecting the relative coverage of these river features in RHS. By using variable clustering, the likelihood of species occurrences could be easily related to the observed habitat. 6. By utilising important methodological developments, this project provides important evidence that RHS forms an effective basis for relating many river birds to their habitats, and that when used in conjunction with the WBBS, could bring valuable benefits to river bird conservation. More generally, the work illustrates how RHS can describe variations in river structure and anthropogenic modification in a manner that is relevant to riverine organisms, along with transferable methods for describing and modelling the resulting relationships.
13
McCleary, Ryan J. R. "Uridinediphosphate-glucuronosyltransferase (UDP-GT) Ontogeny and PCB Effects in Galliform Birds." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35962.
Texte intégralRésumé :
Hepatic UDP-GTs are partly responsible for metabolism of the thyroid hormone, thyroxine (T4), in mammals, but little is known of UDP-GT activity in birds. To determine the ontogenic pattern of UDP-GT activity in precocial birds, we measured activity in Japanese quail (Coturnix japonica) liver at days 12 and 14 of the 16.5-day incubation, 3 perihatch stages and <1, 1, 4, 6, 7, 20 and 42 days posthatch. We used an enzymatic reaction with para-nitrophenol (pNP) as substrate that was validated for quail tissue. The pattern of UDP-GT development included low embryonic activity, increased activity beginning in the perihatch period, a peak in activity at day 4 posthatch and a return to lower activity levels from day 6 to adults. The profile of UDP-GT activity, in relation to the ontogeny of circulating T4 and triiodothyronine (T3) in quail, is consistent with UDP-GT playing a role in regulating circulating T4 and with the perihatch peak in T3 stimulating the posthatch peak in UDP-GT activity. To examine the effects of polychlorinated biphenyls (PCBs) on UDP-GT in developing precocial birds, we dosed chicken (Gallus domesticus) eggs with concentrations of PCB 126 from 0 to 0.80 ng/g egg (in sunflower oil) prior to incubation. Tissues were sampled at day 20 of the 21-day incubation and assayed for plasma hormones and UDP-GT activity. Eggs also were dosed with 0 or 0.25 ng PCB 126/g egg or with 0 or 0.64 ng/g egg of the coplanar PCB 77, allowed to hatch, and sampled at 42 days posthatch. There was no consistent pattern of altered thyroid hormones or UDP-GT activity in developing chickens exposed to either of these coplanar PCBs although previous studies indicated developmental alterations from exposure to the higher doses.<br>Master of Science
14
Wells, D. "The development and application of a signal analysis system for an ornithological radar." Thesis, Cranfield University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380188.
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15
Doherty, Kevin Eric. "Sage-grouse and energy development integrating science with conservation planning to reduce impacts /." [Missoula, Mont.] : The University of Montana, 2008. http://etd.lib.umt.edu/theses/available/etd-03262009-132629/unrestricted/doherty.pdf.
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16
Shearer, Patrick. "Development of novel diagnostic and vaccine options for beak and feather disease virus (BFDV) /." Murdoch University Digital Theses Program, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090720.142800.
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Murdoch University (Ph.D.)--Murdoch University, 2008.<br>Contains three published journal articles at back of thesis. Thesis submitted to the Faculty of Health Sciences. Includes bibliographical references (leaves 196-231)
17
Han, Yi. "Development and Evaluation of Mucoadhesive Chitosan Nanoparticle-based Salmonella Vaccine for Oral Delivery in Broiler Birds." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587571015936815.
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18
Kuan, Soh Leh. "Determining the roles of Nel in the development of the avian visual system." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=192183.
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Cell-cell signalling molecules play important roles in neural development. In response to extracellular signals, neuronal progenitor cells proliferate, differentiate, and form a neuronal network. In the vertebrate retina, retinal ganglion cells (RGCs) are the first neurons produced during development and are the only neurons that send projections to the brain. However, the molecular mechanisms for RGC development have not been fully understood. In this study, I have investigated the expression and functions of Nel (Neural Epidermal Growth Factor Like), an extracellular glycoprotein that contains chordin-like domains and epidermal growth factor-like domains, in the development of the chick RGCs and retinotectal projection. I found that on embryonic days (E) 2-3.5, Nel was expressed in the presumptive retinal pigment epithelium of the developing eye. Correspondingly, Nel-binding activity (Nel receptor activity) was detected in the retinal pigment epithelium and also the progenitor layer of the neural retina. At the early stages during RGC formation, Nel overexpression increased the total number of RGCs and accelerated the progression of RGC differentiation wave. Conversely, Nel expression knockdown decreased the total number of RGCs and slowed down the progression of RGC differentiation wave. At later stages (E3-E18), expression of Nel in the retina was in the retinal pigment epithelium and the RGC layer, whereas receptor activity for Nel was localized in the retinal pigment epithelium and the RGC axons. In vivo, Nel overexpression in the developing retina induced the inhibition of RGC axons and thus disrupting the intraretinal RGC axon projection. These results suggest that Nel can positively regulate the production of RGCs at the early stages during retinal development, and at the later stages, Nel can function as an inhibitory guidance cue in vivo for RGC axons.
19
Stallard, Lana C. "The effects of different iodine availabilities on thyroid function during development in Japanese quail." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/45196.
Texte intégralRésumé :
Day 14 embryos (16.5-17 day incubation period) and 1 day old chicks of Japanese quail (Coturnix japonica) were used to study the effects of different egg iodine (I) availabilities on thyroid function during development. Low (≤50 μgI/kg feed in the maternal diet) and high (1200 μgl/kg feed) I availability were compared to control levels (800 μgI/kg feed).
Thyroid gland (TG) content of I, triiodothyronine (T3), and thyroxine (T4), plasma concentrations of T3 and T4, and hepatic 5’ monodeiodinase (5’-D) activity was measured, and the response of the TG to thyrotropin (TSH) stimulation [TG-cAMP content and plasma thyroid hormone (TH) concentrations]. Also, the developmental patterns of TH concentrations in the TG and plasma were determined.
With increased I availability, TG-I content is elevated but thyroidal T4 and T3 and the developmental pattern of TG-TH were not different from controls. Plasma T3 and T4 and the developmental pattern of plasma TH were not altered. Indicators of the TG response to TSH stimulation were not different with increased I availability. Hepatic 5’-D activity did not differ between control and high I availability. Reduced body weight was associated with increased I availability. In general, TG weight was not altered, but a small percentage of the high I birds exhibited TG hypertrophy and altered TG function.
With low I availability, TG-I content was reduced. Although thyroidal T4 content was reduced on embryonic day 14 and thereafter, TG-T3 was maintained throughout development. The magnitude of the TG response to TSH stimulation was not altered with reduced I availability. Hepatic 5’-D activity, plasma TH concentrations and the developmental patterns of plasma TH were not different between control and low I availability. Reduced I availability did not affect body or TG weight.
Developing Japanese quail exhibit excellent ability to adjust thyroid function over a wide range of I availabilities. Regulation appears to occur at TH synthesis which allows most aspects of thyroid dynamics to remain unchanged in the maintenance of circulating TH concentrations.<br>Master of Science
20
Amran, N. (Noor). "Flocking birds of different feathers:exploring educators’ perceptions on the use of interdisciplinary collaborations in professional development (pd) programs." Master's thesis, University of Oulu, 2016. http://urn.fi/URN:NBN:fi:oulu-201606042361.
Texte intégralRésumé :
This is a pragmatic study of educators’ perceptions of interdisciplinary collaborations in professional development (PD) programs for educators. This study draws on a social-constructivist view of learning and specifically on the Deweyan pragmatic theory of knowledge. Key concepts such as interdisciplinarity, homophily, inter-, multi- and transdisciplinary collaborations, and PD programs for educators are discussed in light of this perspective.
A literature review shows that interdisciplinary collaborations have been used widely across disciplines as a platform for professionals to interconnect and solve societal problems. However, such collaboration is scarce between educators and other members of other disciplines. Therefore, a gap is identified under the topic of incorporating interdisciplinary collaboration into PD programs for educators.
Thus, this study aims to provide textured, triangulated, and descriptive data from educator-participants’ perceptions about interdisciplinary collaborations for the improvements of the current practice in PD programs. The research questions are: (1) to explore educators’ perceptions about the use of interdisciplinary collaboration in PD programs and (2) to examine their perceptions about the factors that can make interdisciplinary collaborations work in this setting.
This study was framed within a pragmatic research paradigm and is designed based on the concurrent (triangulated) mixed-methods research approach. The university program, Oulu EduLAB, was identified and selected as a site for data collection since it integrates the LAB studio model in its program structure, which supports interdisciplinary collaborations. Both quantitative and qualitative data were collected from educator-participants in Oulu EduLAB through an online survey. Then, inferences were concurrently constructed from these two sets of data to investigate the research questions.
Overall, findings show that 88% of respondents in this study perceived interdisciplinary collaborations as important in PD programs. Respondents gave several reasons for this opinion, among others: interdisciplinary collaboration is a necessity in the 21st century education, this type of collaboration allows them to improve their own skills, and that they learn new and different things from people of other disciplines. Respondents also rated communication factors as the most important factor in ensuring the success of interdisciplinary collaboration. The highest rated factor was ‘Mutual trust and respect’ while the least rated factor was ‘Each member has a unique purpose in the team’. Finally, both practical and philosophical implications on the use of interdisciplinary collaborations in PD programs are discussed based on the data collected from the survey.
21
Begehold, Heike. "Impact of naturalness-promoting beech forest management on the forest structure and the diversity of breeding birds." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-224738.
Texte intégralRésumé :
Currently, existing European beech forests (Fagus sylvatica L.) are scarce and fragmented across vast parts of their potentially natural distribution. About 25 % of the global range of beech forests is located in Germany. Thus, Germany has a particular responsibility to integrate biodiversity conservation aspects into beech forest use. In this thesis, the influence of naturalness-promoting management on forest structure and breeding birds was investigated – in comparison to management without a biodiversity focus (different management) and forests sites that have been unmanaged for different periods of time (recently: unmanaged for 14-32 years as of 2012, and long-term: unmanaged for 65 years or since at least 1900). With a total area of 714 ha, 22 study sites located in the northeastern part of Germany were studied. Forest structure was studied using forest development phases (FDPs), which divide the forest life cycle into different periods. FDPs are characterized by a defined combination of five structural parameters such as canopy cover, diameter at breast height, tree height, regeneration cover and deadwood amount. FDPs were mapped during the winters of 2012 and 2013 according to a dichotomic decision tree. Breeding bird abundances were determined in 19 study sites and each study site was mapped 10 times between March and July of the same years using a territory mapping method. FDP patterns such as proportions, patch sizes, distances between patches of the same FDP, evenness, FDP transition within a decade and transition diversity, as well as bird abundances and development of bird densities within a decade were analyzed.
Study sites under naturalness-promoting management differ clearly from differently managed sites and they are comparable or develop similarly to (long-term) unmanaged stands regarding FDP patterns. This also applies for the composition of the breeding bird community and the development of breeding bird species within a decade. The effect of naturalness-promoting management within the last decade is strong as evidenced by: significant decreases in FDP patches in size, the development of FDP richness towards a complete set; the comparability of transition proportion and transition diversity with long-term unmanaged sites (for former gaps, regeneration phase, early-, mid- and late optimum phase as well as disintegration phase); the higher total abundances of all breeding birds as compared with differently managed and recently unmanaged sites; and the highest number of increasing bird species amongst all management types. Further, the occurrence of breeding birds is linked to FDPs. On the one hand, the breeding bird community has a strong preference for FDPs of later-stages such as the terminal and disintegration phases. On the other hand, every bird species has its own set of preferred and avoided FDPs and every FDP has several bird species preferring it. Thus, a complete set of all FDPs at small scale is necessary for the habitat requirements of birds inhabiting beech forests.
In conclusion, 1) the positive impact of naturalness-promoting management on forest biodiversity is already detectable after a decade and 2) FDPs are a suitable indicator can be used as an innovative indicator for monitoring the impact of forest management on biodiversity.
22
McCurdy, Jason D. "The effects of human development on avian diversity along an urban-rural gradient in Iowa City, Iowa." Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/2119.
Texte intégralRésumé :
The human population is rapidly urbanizing. While this will undoubtedly present challenges for humans it will also place pressure on birds in these areas. To better manage these spaces in a manner that promotes avian biodiversity, we must first come to understand how human development affects the distribution and abundance of bird species and guilds within cities and if patterns observed previously in large cities can be extended to smaller ones.
Breeding birds were surveyed along a gradient of increasing urbanization in Iowa City, Iowa, during the summers of 2014 and 2015. Study areas included a forested park, recreational park, low density residential area, medium density residential area, high density/mixed-use area, and urban core. Birds were censused a total of four times at each site using variable circular plot counts. Landscape characteristics were measured using a high resolution land cover dataset and tree canopy model. Regression models were developed to investigate relationships between the bird community and land cover characteristics.
Bird species richness, diversity, and evenness all decreased with increasing urbanization, while biomass and the number of individuals peaked in the urban core. The community shifted from non-native, resident, granivorous, multi-brooding building nesters in highly developed areas to native, migrant, invertivorous, single-brooding, tree and tree cavity nesters at the least developed sites. Regression models indicated varied relationships among landscape characteristics and species richness and community prevalence of functional guilds. Native, migratory, invertivorous, tree cavity-nesting, and single-brooding species showed negative relationships to variables measuring the built environment, while non-native, resident, granivorous, building nesting, and multi-brooding species showed positive relationships to these measures.
Overall, the response of avian functional guilds to varying levels of urban intensity in Iowa City were remarkably similar to the results of previous studies. This suggests that much of what has been learned previously concerning avian responses to human development can be extended to planning and implementing conservation strategies in smaller cities.
23
Cooper-Mullin, Clara. "Metabolic rates of cultured skeletal muscle of Coturnix quail selected for different rates of growth." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1386017554.
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24
Uysal, Ahmet Kerim. "Effects of an Early Life Immune Challenge on Body Growth, Personality, Mating Behaviors, and Brain Development of Zebra Finches (Taeniopygia guttata)." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6969.
Texte intégralRésumé :
The developmental stress hypothesis predicts that an aversive condition, such as decreased food intake, predation, and social isolation, in the early developmental stage could have long term effects on behaviors and brain development of an animal. In nature, bird nestlings are susceptible to various factors, such as malnutrition, infections, and parasites. Effects of early life stress on adulthood have been extensively studied with some stressors including malnutrition. However, immune challenges as an early life stressor and their long-term programming effects on adult behaviors are yet to be studied in detail. The goal of the current study was to investigate changes in growth rate, personality, mate selection behaviors and brain development in zebra finch nestlings after injection with a viral infection mimicking agent, Polyinosinic: polycytidylic acid (Poly I:C). By using Poly I:C, it was possible to isolate long-term effects to the immune response of the bird. After Poly I:C injection on post-hatch day (PD) 14, morphological measures were conducted to detect changes in body growth rate. When birds became sexually mature (> ~PD 200), behaviors of birds were observed in different conditions to detect changes associated with the personality traits of animals. In mate choice trials, both attractiveness of males and mate selection behaviors of males and females were investigated. Finally, the development and neuronal activity of specific brain nuclei involved in courtship (i.e., HVC and RA) and social/sexual behaviors (nucleus taeniae of the amygdala, TnA) were investigated. The results showed that nestlings’ growth rate was not affected. However, Poly I:C injection had some effects on certain, but not all, personality traits observed in the study. Such effects were found only in female zebra finches, suggesting that there was a limited sex-specific influence of an early life immune challenge on personalities of adults. The results also showed that Control females tended to choose untreated males over Poly I:C injected males in mate choice trials. Finally, Poly I:C injection negatively affected the overall development of targeted brain nuclei. In addition, neuronal activity in TnA was higher in Poly I:C injected birds. Results of the present study suggest that one time injection with Poly I:C early in the life causes long term effects on adulthood. These findings are further discussed regarding their relevance to the developmental stress hypothesis.
25
Fergusson, D. "The effects of 4-hydroxycoumarin anticoagulant rodenticides on birds and the development of techniques for non-destructively monitoring their ecotoxicological effect." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239503.
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26
ASANTE, MELDOMI ASABEA. "EFFECT OF URBAN RIPARIAN DEVELOPMENT ON BIODIVERSITY; USING BIRDS AND VEGETATION AS ECOLOGICAL INDICATORS IN COOPER CREEK LOCATED IN SOUTHWEST OHIO." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1146157392.
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27
Kilgas, Priit Kilgas Prit. "Blood parameters as indicators of physiological condition and skeletal development in Great Tits (Parus major) : natural variation and application in the reproductive ecology of birds /." Tartu : Tartu University Press, 2007. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=9789949117697.
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28
Godinez, Ricardo. "Comparative Genomics of the Major Histocompatibility Complex in Amniotes." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10685.
Texte intégralRésumé :
The major histocompatibility complex region (MHC) is a multi gene family present in all jawed vertebrates, with a fundamental role in vertebrate immunity. More than two decades of studies have resulted in the characterization of over a dozen MHC regions, and models of evolution explaining that the MHC has gradually increased in size and gene content since its origins without addressing their genomic context or the environmental selective forces. Furthermore, a compelling reconstruction of the evolutionary history of the MHC has been hampered due to phylogenetic gaps and the absence of comparative phylogenetic methods applied to comparative genomics. Here I reconstruct 320 MY of MHC evolution using 42 amniote genomes using improved gene annotations, genomic alignments and phylogenetic algorithms to reconstruct the evolution of the MHC at three levels of phylogenetic resolution. The first one describes 25 MY of evolution of the primate MHC using eight Human and four non-Human primate MHC haplotypes. Results suggests that highly dense gene segments have a strikingly conserved gene organization, and six conserved and highly rearranging segments overlap genes that are most commonly associated to disease. Phylogenomic analysis implies that the MHC has remained stable in gene content and size, with significantly increased duplication rates in the primate ancestors. The second one describes 280 MY of MHC evolution through the first characterization of reptilian MHC region, which combines mammalian, reptilian, Bird and amphibian characteristics, which favors the hypothesis of the existence of a primordial MHC in which natural killer receptors, CD1 and lectin genes co-exist. The Anolis MHC expands our understanding of the origins of the exceptionally small Bird MHC regions and provides further information about the organization and size of the ancestral amniote MHC. The third one compares 42 amniote MHC regions and map gene duplications and losses to further evaluate the mode and tempo of the evolution of the region. Comparative phylogenetic methods imply that the genomic and environmental factors affect the diversification of MHC during 320 My of evolution.
29
Boscolo, Danilo. ""O uso de técnicas de play-back no desenvolvimento de um método capaz de atestar a presença ou ausência de aves no interior de fragmentos florestais"." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-16062003-175155/.
Texte intégralRésumé :
Nosso objetivo foi desenvolver um método para atestar a presença ou ausência de seis espécies de aves (Basileuterus leucoblepharus, Batara cinerea, Carpornis cucullatus, Chiroxiphia caudata, Pyriglena leucoptera e Trogon surrucura) em fragmentos florestais. Foi determinado o horário do dia e época do ano em que o play-back é mais eficiente em atestar a presença dessas aves. Os testes ocorreram na Reserva Florestal do Morro Grande (Cotia, SP). Três horários foram testados (manhã, meio do dia e tarde) ao longo de um ano. O teste G verificou a variação de eficiência entre os diferentes horários, e o teste de Rayleigh a variação anual. A manhã e o meio do dia apresentaram-se mais eficientes que a tarde para B. leucoblepharus, C. caudata e T. surrucura. A única ave a apresentar uma época do ano mais eficiente foi B. cinerea. Para avaliar sua eficiência, a capacidade do método em atestar a presença das aves em 13 fragmentos foi correlacionada com sua abundância nos mesmos. Os testes ocorreram quatro vezes em cada área nos momentos de maior eficiência. Os resultados indicam que C. caudata seja recenseada pelo menos duas vezes por fragmento. Três visitas é o mínimo para B. cinerea, B. leucoblepharus, P. leucoptera e T. surrucura. Para C. cucullatus deve-se ser repetir quatro vezes. O método foi criado para gerar rapidamente dados de presença e ausência em grande quantidade de fragmentos. Essa informação pode auxiliar estudos sobre dinâmica de metapopulações destas espécies.<br>In order to provide rapid access to presence/absence data of six species of birds (Basileuterus leucoblepharus, Batara cinerea, Carpornis cucullatus, Chiroxiphia caudata, Pyriglena leucoptera and Trogon surrucura) inside forest fragments, an efficient playback method was developed. The broadcast of these birds vocalizations was carried out at the Morro Grande Forrest Reserve (Cotia, SP). Playback tests were executed three times a day (sunrise, noon and before sunset) during one year. Daily and seasonal variations in the efficiency of the play-back were tested with G-statistics and the Rayleigh test. Sunrise and noon were more efficient than the period before sunrise to B. leucoblepharus, C. caudata and T. surrucura. The only species to show an annual period of higher rate of response was B. cinerea. To evaluate the real efficiency of the method, 13 forest fragments were surveyed for presence of these birds. The data was compared to the abundance of the birds in these areas. Each fragment was surveyed four times. At least two surveys are needed for C. caudata. Three surveys are the minimum effort to access the distributional pattern of B. leucoblepharus, B. cinerea, P. leucoptera and T. surrucura. Due to its rarity, C. cucullatus must be censused not less than four times. The method developed in the current study was created to provide a rapid access to the patch occupancy patterns of these six species in a large number of fragments. That kind of data may be very useful in studies about metapopulation dynamics and conservation ecology.
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Fries, Anthony Charles. "The effect of migratory activity of waterfowl on the evolution and ecology of influenza A viruses." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1439893550.
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Cerio, Donald Greene. "The Visual Apparatus of Avian Dinosaurs and Other Diapsids: Anatomical Correlates of Behavior and Evolution." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1565617073174635.
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Berg, Cecilia. "Environmental pollutants and the reproductive system in birds : Developmental effects of estrogenic compounds." Doctoral thesis, Uppsala University, Department of Evolutionary Biology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-501.
Texte intégralRésumé :
<p>A number of environmental pollutants have been shown to mimick the action of the female sex hormone estrogen and are, therefore, suspected to be responsible for reproductive abnormalities seen in wildlife. Test systems which can be used in hazard and risk assessment of chemicals with estrogenic effects are consequently needed. In this thesis, I propose the avian egg as an <i>in vivo</i> test system for estrogenic compounds. I conclude that malformation of the left testis and the Müllerian ducts (MDs: embryonic oviducts) in avian embryos can be used as endpoints to examine estrogenic activity of chemicals. MD malformation is more easily determined and thereby faster to use as an endpoint than histologically observed feminization of the testis. The usefulness of MD/oviduct malformations as biomarkers for estrogenic effects in wild birds should be considered. </p><p>The environmental pollutants bisphenol A (BPA) and <i>o,p´</i>-DDT induced similar effects as the synthetic estrogens, ethynylestradiol and diethylstilbestrol. BPA caused MD malformations in quail embryos and ovotestis formation in chicken embryos. <i>o,p´</i>-DDT induced MD malformations in both quail and chicken embryos and ovotestis in chicken embryos. The flame retardant, tetrabromobisphenol A did not induce estrogen-like effects in quail or chicken embryos, but showed a relatively high embryolethality. </p><p>Embryonic exposure to estrogen caused persisting malformations of the oviduct, as well as a changed distribution pattern of the enzyme carbonic anhydrase in the shell gland of adult females. Considering the crucial role of carbonic anhydrase in shell formation, such changes could result in decreased shell quality. I propose that eggshell thinning in avian wildlife could reflect a functional malformation in the shell gland that is induced by xeno-estrogens during embryonic development, rather than being caused by exposure of the adult bird to environmental pollutants. This hypothesis opens new possibilities for studying the mechanisms behind contaminant-induced eggshell thinning in birds.</p>
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Gluckman, Thanh-Lan. "The mechanisms underlying convergent evolution in the plumage patterns of birds." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/247220.
Texte intégralRésumé :
Convergent evolution is a central theme in biology. Birds are an ideal system to examine the mechanisms underlying convergent evolution. Although bird patterning is diverse, within-feather patterns have repeatedly converged on the same four types: mottled patterns, scales, bars and spots. Other avian patterns occur, e.g. stripes, but are rare. In my thesis I examine the four main mechanisms underlying convergent evolution in plumage patterns: evolutionary genetics, evolutionary development, natural selection for signaling and camouflage. Japanese quail (Coturnix japonica) is a model system in developmental biology. Examining the developmental basis of pattern formation using molecular techniques, the dorsal patterning of embryonic quail is likely due to activation of the melanocortin-1 receptor, which is a highly conserved pathway in vertebrates. I examined whether a reaction-diffusion based theoretical model of pattern formation may predict developmental constraint in two groups that have different lifestyles and spectacular patterns: waterfowl (Anseriformes) and gamebirds (Galliformes). Tracing the evolutionary trajectory of pattern evolution with Bayesian comparative modeling there was evidence for developmental constraint in pattern evolution. Adaptive explanations may also result in convergence. Cuckoo-hawk mimicry has been demonstrated in the common cuckoo (Cuculus canorus) and the Eurasian sparrowhawk (Accipiter nisus), but may be prevalent in Old World cuckoos. Randomly selecting a parasitic cuckoo from each genera of Old World cuckoos and <8 sympatric raptors, I quantified their barred patterns using digital image analysis and found that parasitism can explain convergent evolution in the patterns of parasitic cuckoos and raptors. Patterns may have evolved due to ecological selection. Examining the patterns of 80% of all avian species worldwide, I found that habitat does not predict patterning, and that all four patterns are found in all habitats. These results demonstrate that the mechanisms of convergent evolution are diverse, and that development and natural selection have contributed to pattern evolution.
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Wang, Biao. "Development and Application of Genomic Resources in Non-model Bird Species." Doctoral thesis, Uppsala, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-183645.
Texte intégralRésumé :
Understanding the genetic basis of biological processes is a fundamental component of modern ecology and evolutionary biology studies. With the recent advent of next generation sequencing (NGS) technologies, it is now possible to perform large genome and transcriptome projects for ecologically important non-model species. In this thesis, I focused on the development and application of genomic resources of two non-model bird species, the black grouse (Tetrao tetrix) and the great snipe (Gallinago media). Using the chicken genome as a reference, I developed a reference guided NGS pipeline to assemble the complete draft genome of black grouse. The draft genome has a good coverage of the main 29 chromosomes of the chicken genome. The genome was used to develop a vast number of genetic markers. Comparing this genome with that of other species, I identified the genomic regions which were important for the lineage specific evolution of black grouse. I also sequenced and characterised the spleen transcriptome of the black grouse. I identified and validated a large number of gene-based microsatellite markers from the transcriptome and identified and confirmed the expression of immune related genes. Using a similar RNA-Seq approach, I also sequenced the blood transcriptomes of 14 great snipe males with different mating success. I identified genes and single nucleotide polymorphisms (SNPs) which might be related to male mating success in this species, both in terms of gene expression levels and genetic variation structure. For the immunologically important major histocompatibility complex (MHC) gene region of black grouse, I constructed a fosmid library and used it to sequence the complete core MHC region of this species. This resource allowed me to perform a comprehensive comparative genomics analysis of the galliform MHC, by which I found that some genes in this region were affected by selective forces. I was also able to develop a single locus genotyping protocol for the duplicated MHC BLB (class IIB) genes and found that the two black grouse BLB loci followed different evolutionary trajectories. This thesis set an example of developing genomic resources in non-model species and applying them in addressing questions relevant to ecology and evolutionary biology.
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Vennerholm, Linn. "Ontogeny of personality in red junglefowl chicks, Gallus gallus." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78996.
Texte intégralRésumé :
Many studies have been performed on animals to study their behavior, but not as many on the development of behavior, and not yet on chickens. Therefore, 42 red junglefowls were tested in three Novel Arena, Novel Object and Tonic Immobility tests to investigate the ontogeny of personality. Several behaviors were stable over time in the Novel Arena and Novel Object tests, and are a part of the bird’s personality, while other behaviors were plastic. The stability of the behaviors increased over time. The decrease in duration of the Tonic Immobility can be due to decreased stress during the length of the study. The study showed that personality can be detected early in a chicken’s life, even though a lot of the observed behaviors change. Further studies are needed to figure out duration of the stability and why certain behaviors are stable.
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Haslam, Sue M. "The development of a unitary index for the assessment of welfare in broiler chickens." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274831.
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Lindström, Karin M. "Bird-parasite interactions : Using Sindbis virus as a model system." Doctoral thesis, Uppsala University, Department of Evolutionary Biology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-486.
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<p>This thesis focuses on the evolutionary interactions between birds and a parasite, the mosquito-borne Sindbis virus (Togaviridae, <i>Alphavirus</i>). In conclusion, the results show that the Sindbis virus is widespread among birds, and that the fitness of infected hosts may be reduced by the virus. Furthermore, viruclearance ability was revealed by male plumage traits, and viraemia was related to hormonal- and social status.</p><p>The distribution of Sindbis virus infections among passerine birds was examined in five areas in Sweden. Almost all species tested were infected, and three species of thrushes weridentified as the main hosts. In a series of experimental infections, greenfinches (<i>Carduelis chloris</i>) kept in aviaries were used ahosts. First, the behavioural consequences of an infection were investigated. During the infection, birds tended to reduce thespontaneous locomotion activity, and when escaping from a simulated predator attack, infected birds had reduced take-off spee Furthermore, when comparing virus clearance rate between male greenfinches, I found that males with large yellow tail ornaments hafaster virus clearance rates as compared to those with smaller ornaments. Thus, male virus clearance ability was honestly revealed by the size of an ornament. Moreover, males with experimentally elevated testosterone levels experienced a delayed, but not increased viraemia as compared to controls. When the relationship between male social ranand viraemia was examined, I found no evidence that high-ranked males suffered reduced rank during the infection. Nevertheless, viraemipatterns of males were related to their social rank, so that low-ranked birds had a delayed viraemia as compared to high-ranked birds. </p>
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Holmström, Linn. "Can the environment and bird species have priority over economic interests? : A study of the protection of protected areas, bird species and their habitats." Thesis, Linnéuniversitetet, Ekonomihögskolan, ELNU, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-21288.
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Human enlargement and improvements are following the same scheme as the world economies, and have through the same structure damaged and overexploited the ecological systems of the Earth, leading to a progressive degradation of its biodiversity. The need for protected areas is now inescapable when it comes to restoring species while sustainable development and prevention of damaging the environment have become prominent. It is now even more important that the awareness of an actual impact of our living standards on the ecological system has been established. International and more specifically European Laws have been established to prevent and ensure species of all kinds to live in a safe and preserved environment, but the question of their effectiveness has to be asked and nuanced. In that respect the issue of bird species is one of major importance as they are victims of human development. Within the European member states the problem is coming from the inability of some of them to implement and apply European laws because all do not agree on the terms of a protection provided for bird species.
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Stetzer, Randy T. "Immunological and Developmental Effects of Polybrominated Diphenyl Ethers (PBDEs) and 2,3,7,8-tetrachloro-p-dioxin (TCDD) in Birds." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1189789668.
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Schwindt, Stefan. "Metholdologies for simulating soft-body impacts and development of an improved artificial bird." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510220.
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Maduri, Vaishnavi. "MODELING, SIMULATION AND EXPERIMENT FOR THE DEVELOPMENT OF INFRASOUND BIRD STRIKE PREVENTION SYSTEM." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1436806166.
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Zakrajsek, Edward J. "Development of a Bird-Avoidance Model for Naval Air Facility El Centro, California." DigitalCommons@USU, 2001. https://digitalcommons.usu.edu/etd/6587.
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Bird strikes ( collisions between birds and aircraft) pose a significant threat to aviation safety. For example , Naval Air Facility El Centro, California, lost an F-18 jet to a bird strike in October 1995. To help combat the bird-strike threat at Naval Air Facility El Centro, I developed a bird-avoidance model as a risk-management tool for the installation. It can be used to schedule flights at NAF El Centro and its two associated practice-bombing ranges during times of low-bird activity. I calculated bird-strike risks and published them in web-page format on both the installation's server and the USGS/Utah State University, College of Natural Resources' server for easy access by flight crews, flight-safety officers, airfield managers, natural resource managers, and other Navy personnel.
Bird hazards during daylight hours were quantified using daily bird counts through the year 2000. These were combined with a bird-hazard index for various species, developed using U.S. Air Force bird-strike records. Nocturnal bird hazards were quantified in the fall of 2000 using a bird-radar system to count birds in three relative size classes. Large- and medium-sized birds were scaled to represent a higher risk to aircraft than small birds. Nocturnal bird hazards beyond the fall study were estimated using U.S. Air Force bird-strike records.
The main section of the web page allows the user to select the area and time of year, which links to the appropriate color-coded bird-strike-risk graph. The graphs describe the bird-strike risk by time of day and altitude with red for high risk, yellow for moderate risk, and green for low risk. The web page also identifies and describes the most hazardous bird species in the area, recommends methods of hazard management, and provides links to bird-strike-information sources on the web.
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Shih, Wan-Yu. "Optimising urban green networks in Taipei City : linking ecological and social functions in urban green space systems." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/optimising-urban-green-networks-in-taipei-city-linking-ecological-and-socal-functions-in-urban-green-space-systems(eca36d35-4470-4fdf-a766-ba9eebe5ca63).html.
Texte intégralRésumé :
With the global population becoming more urban and less rural, increasingly research has argued for concepts such as establish Green Infrastructure (GI) as a tool for enhancing wildlife survival and human’s living quality (e.g. Harrison et al., 1995; Benedict and McMahon, 2006). However, an interdisciplinary planning approach underpinned by ecological and social evidence has not yet been fully developed. This research therefore seeks to integrate an ecological network with a green space planning standard by exploring the use of biotope and sociotope mapping methods. Seeking a comprehensive planning that takes all green resources into account, a green space typology is firstly developed according to Taiwanese contexts for identifying green spaces from land use maps. In order to specify effective features of these green spaces to bird survival and user preferences, an insight was conducted into the relationship of ‘birds and urban habitats’, as well as ‘human preferred urban green spaces’ in Taipei City. Important environmental factors influencing bird distribution and influencing human experiences in urban green spaces are respectively specified and developed into an ecological value index (EVI) to detail potential habitats and a social value index (SVI) to evaluate recreational green space provision. Interestingly, proximity to green space appears to plays a more critical role in human preferences than bird survival in Taipei city; size is important both as a habitat and for creating an attractive green space; and green space quality tends to be a more significant factor than its structure for both wildlife and people. Utilising the bio-sociotope maps, this thesis argues for a number of strategies: conserving, enlarging, or creating large green spaces in green space deficient areas; increasing ecological and recreational value by enhancing green space quality of specific characteristics; and tackling gravity distance by combining green space accessibility and attractiveness in optimising urban green structure. As these suggestions are a challenge to apply in intensively developed urban areas, barriers from land use, political mechanisms, technical shortages, and cultural characteristics are also explored with possible resolutions presented for facilitating implementation. It is clear that optimising a multifunctional GI for both wildlife and people requires interdisciplinary knowledge and cooperation from various fields. The EVI and SVI developed within this thesis create the potential for a more place-specific and quantifiable green spaces strategy to help better link ecological and social functions in urban areas.
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Larsen, Elise Anne. "Effects of Urban Development on Breeding Bird Diversity: The Role of Diet and Migration." W&M ScholarWorks, 2008. https://scholarworks.wm.edu/etd/1539626872.
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Chandler, Brendan. "The SH2 Domain-Containing Adaptor Protein SHD Reversibly Binds the CRKL-SH2 Domain and Knockdown of shdb Impairs Zebrafish Eye Development." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/878.
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The adaptor protein CT10-Regulator of Kinase (CRK) and the closely related CRK-Like (CRKL) are adaptor proteins that play important roles in many signaling pathways regulating cell proliferation and cell motility. A notable example is their required role in Reelin signaling during development of the laminated structures of the vertebrate central nervous system, including the cerebral cortex, cerebellum, hippocampus, and retina. As adaptors, CRK/CRKL are important in coupling phosphotyrosine signaling to G protein activity to regulate both cell proliferation and changes in the actin cytoskeleton, thereby exerting control over cell motility, and migration. While many proteins that interact with CRK/CRKL have been identified, the diverse roles of these molecules suggest that more remain to be found.
Herein is described a novel CRK/CRKL interacting protein, Src Homology 2 domain-containing protein D (SHD), which demonstrates a phosphorylation-dependent interaction with the CRK/CRKL SH2 domain in HEK 293 cells stimulated with hydrogen peroxide, which globally boosts tyrosine phosphorylation by inhibiting tyrosine phosphatases. Treatment with an inhibitor for Src family kinases (SFKs), Src-1, or an inhibitor of Abl/Arg kinases, STI571, reduces peroxide-induced binding of the CRKL-SH2 domain to SHD. We show that overexpression of Abl kinase, but not the SFK Fyn is sufficient to induce binding of the CRKL-SH2 to SHD and that this interaction requires at least one of the five tyrosines in YxxP motifs found in SHD. Using mass spectrometry, we found that Abl phosphorylates SHD on Y144, which is located in a YxxP motif. Mutation of this site to phenylalanine reduces, but does not prevent, Abl-induced binding of SHD to the CRKL-SH2 domain, suggesting that other YxxP sites also facilitate the interaction. A discussion of the cellular consequences of the interaction between SHD and CRK/CRKL is presented.
To explore the biological role of SHD, we used the zebrafish to study shdb, a putative ortholog of human SHD. The expression of shdb was unknown and so we performed in situ hybridization and determined that shdb was expressed in the developing nervous system. To study the function of this gene, we used a morpholino to knock down expression of shdb which resulted in significantly reduced eye size. Possible roles of Shdb in eye development are discussed as is future research aimed to elucidate the cellular and developmental mechanisms by which Shdb functions in the developing eye.
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Bhullar, Bhart-Anjan Singh. "The evolution and development of the archosaurian head and the origin of the bird skull." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11667.
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Abstract: Archosauria, the "ruling reptiles," characterized along their stem by relatively large, macrocarnivorous animals, are today represented by two enormously successful but divergent extant clades: Aves, the birds, and Crocodylia, the crocodiles and alligators. This thesis seeks to characterize major transformations in the cranial region of archosaurs, a prominent theme in their evolution.
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Wade, Helen Mary. "Investigating the potential effects of marine renewable energy developments on seabirds." Thesis, University of the Highlands and Islands, 2015. https://pure.uhi.ac.uk/portal/en/studentthesis/investigating-the-potential-effects-of-marine-renewable-energy-developments-on-seabirds(a13794b8-f416-4e96-8199-5fbd3af39d32).html.
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Marine renewable energy developments (MREDs) are becoming an increasing feature of the marine environment. Scotland has considerable potential for generating energy from the marine environment in the form of extensive wind, wave and tidal-stream resources. Scotland also hosts numerous internationally important breeding populations of seabirds and Scottish territorial waters represent a key overwintering area for many species. EU legislation requires that MREDs do not damage the integrity of protected seabird populations but potential effects of MREDs on seabirds are not yet fully understood. This thesis aims to address gaps in knowledge regarding how MREDs may affect seabird populations. I generate vulnerability and confidence indices to predict the effects of offshore wind, wave and tidal-stream renewable energy developments on Scottish seabird populations; track the movements of a seabird species identified as lacking in data to better understand overlap with MREDs; and investigate seabird use of a high current flow environment leased as a tidal-stream energy development site. Overall, this thesis indicates that seabird responses to MREDs are likely to be species-specific and will vary dependent on the development location and design of the energy generating technology. My findings indicate that effects of MREDs will differ dependent on individual foraging strategies, age and life stage of individuals, which implies that MREDs are likely to differently affect subsections of seabird populations.
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Todd, James, and Wallace E. Jr Dixon. "Temperament Moderates Responsiveness to Joint Attentional Bids at 11 and 14 Months." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/4940.
Texte intégralRésumé :
An increasing number of researchers have begun to identify relationships between dimensions of infants’ and toddlers’ temperament and their language development. Proclivities to engage in joint attention have also been implicated in children’s language development. The purpose of the present investigation was to explore whether aspects of children’s temperament typically associated with linguistic performance could be observed to moderate the joint attentional responsiveness of 11- and 14-month-olds in a controlled laboratory setting. Forty-seven infants (22 females, 25 males) were drawn from a larger study investigating infants’ gaze-following abilities, and included 25 11-month-olds and 22 14-month-olds. In a laboratory setting, two identical objects were placed on opposite sides of the room to the right and left of the infant, respectively. Colorful shower curtains served as background contexts for the objects, and differed in pattern. Experimenters looked at either the right or left object, and infants were scored as to whether they followed the gaze of the experimenter during 1) an initial training phase of 8 trials, and 2) a subsequent testing phase of 8 more trials. Background contexts were switched for half the children during test trials. Temperament played a considerable role in moderating children’s gaze-following at both ages, contributing to 15 significant interactions with factors affecting gaze-following. At 11 months, gaze-following was primarily associated with temperament dimensions reflecting surgency and executive control. For example, perceptual sensitivity, a subcomponent of surgency, entered into a significant 3-way interaction [F(1, 21) = 8.00, p = .010] with training phase (initial versus test) and contextual condition (familiar versus novel). Evaluation of the means vis-à-vis post hoc comparisons indicated that children high in perceptual sensitivity decreased their gaze-following over time in both contexts, whereas children low in perceptual sensitivity exhibited a decrease in gaze-following in only the familiar context. At 14 months, in contrast, negative affectivity was primarily involved. Here, low negative affect children exhibited less gaze-following than high negative affect children during the novel test condition, but the reverse obtained in the familiar test condition [F(1, 18) = 4.56, p = .041]. Our results provide additional evidence of the utility of taking children’s temperament into account when exploring their language development. These findings fit within a model of language development in which children’s temperament influences their language development, at least in part, by virtue of its impact on children’s responsiveness to joint attentional bids.
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McWilliam, Wendy Janine. "The ecological effects of a typical housing development on bird species diversity within a forest fragment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51085.pdf.
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Gurguis, Christopher Ignatius. "The Function And Early Ontogeny Of Individual Variation In Conspicuous Begging Behavior In A Passerine Bird." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/338958.
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Increasingly, individual variation is being recognized as an important influence on behavioral evolution. Sources of variation are therefore an important target for research into the development, evolution, and function of behavior. By providing information about the timescale on which individuals are responsive to their environment, patterns of within-individual variation can shed light on function of behavioral variation. Here, I wanted to understand the function of behavioral variation and the genetic and environmental sources of variation in behavior. First, I test the hypotheses that variation in begging signals nestling hunger, need, or quality. Hunger is a short-term response to food deprivation, while need and quality give long-term information about fitness benefits of gaining more food and fitness potential, respectively. Second, I test the hypotheses that variation in begging is due to genetic, permanent environment, common environmental, and maternal effects. I test these hypotheses in the begging behavior of western bluebirds (Sialia mexicana), making repeated measurements across the nestling period. I show that begging behavior is consistent across the nestling period, and that nestling begging intensity increases with food deprivation. Nestlings fed during a given parental visit beg at higher intensity than nestmates, and on average wait longer since their last meal compared to individuals who were not fed in the same visit. These results support the hypothesis that variation in nestling begging signals hunger. I also show that responsiveness to food deprivation is negatively related to condition, but this effect is not consistent across the nestling period. Finally, variation in begging is produced by a common environmental effect that is correlated through time, suggesting that begging is strongly influenced by the nest environment. Together, these results indicate that variation in begging signals short-term changes in hunger and that environmental effects dominate the production of variation in begging.