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Human Predation Risk Effects On Adult, Male White-Tailed Deer Antipredator BehaviorLittle, Andrew Richard 09 December 2011 (has links)
Recreational hunters play an important role in managing white-tailed deer (Odocoileus virginianus); however, the potential for deer to alter behaviors to avoid hunters has not been addressed within the risk-allocation hypothesis. I evaluated magnitude (i.e., hunter density) and temporal variation (i.e., time of day and initial and prolonged exposure) in human predation risk on movements, resource selection, and observation rates of 37 adult male deer in southern Oklahoma. Deer recognized human predation risk by increasing diel path complexity and use of security cover with greater hunter density. Moreover, deer reduced movement rates and tortuosity while seeking out areas with security cover during prolonged exposure. However, tortuosity and use of security cover remained elevated with greater hunter density. These alterations in behaviors subsequently led to a decrease in observation rates during prolonged exposure. My results clearly support the predation risk-allocation hypothesis by the behavioral responses observed with greater hunter density.
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Habitat selection by red-tailed hawks (Buteo jamaicensis) in prairie landscapes managed for enhanced waterfowl recruitmentFontaine, Alain Jacques January 2002 (has links)
No description available.
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Transitional wars : a study of power, control and conflict in executive succession : theatre as representationMeyer, Matthew John, 1948- January 1998 (has links)
No description available.
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The Role of Spatial Heterogeneity in Sexual Selection and the Evolution of Exaggerated Animal WeaponsWilson, Audrey January 2021 (has links)
Sexually selected male weaponry are among the most diverse and elaborate traits seen in the animal kingdom and often aid males in securing resources and mates, providing a fitness advantage to those that bear them. Yet, while intra-sexual competition between males to secure mates is common, weaponry is a rare trait that is observed in few taxa. Building upon previous theory, Emlen predicted that exaggerated animal weaponry evolves when, (i) there is intense competition between males for access to females, (ii) the biology or behaviour of a species generates high variance in male reproductive success, and (iii) competitions between males promote extreme weapon size evolution. While there are many species bearing weaponry that appear to fit these contexts, it has yet to be tested if these conditions are sufficient to initiate the evolution of exaggerated weaponry. For my research, I created three environmental treatments that emulated the three conditions proposed by Emlen. Using these treatments, I conducted experiments using Drosophila melanogaster to examine the effects of spatial structure on natural and sexual selection with a focus on the initial stages of the evolution of exaggerated trait weaponry that arise from this process. From these experiments, I found that the strength of sexual and other components of natural selection vary with environmental complexity and mutational effect. I also found that these environmental treatments generate weak differences in condition dependence and allometry of fly morphological traits that could be indicative of early weapon evolution. With these experiments, I provide the initial framework to test whether the conditions proposed by Emlen are both necessary and sufficient to lead to the initial evolution of exaggerated animal weaponry and demonstrate that these conditions may indeed create the circumstances that allows this evolution to occur. / Thesis / Master of Science (MSc) / Sexual selection drives the evolution of extreme animal weapons that are used in competition between individuals for access to mates, however while competition is common, these traits are rare. Theory predicts that animal weapons will evolve when (i) there is intense competition between males for mates, (ii) there is high variance in male reproductive success, and (iii) competitions between males mostly occur as duels. For my research, I created three environments that emulated these conditions to differing extents and used the fruitfly as a model to see how these conditions influence the initial stages of animal weapon evolution. I found that these environments are variable in their effects on sexual selection and create morphological differences that could indicate early weapon evolution. With this research, I provide the initial framework to test whether these conditions can create the circumstances for the initial evolution of exaggerated animal weaponry to occur.
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Some Factors Associated with Teacher Placement in Texas.Ramsey, Lewis Slaton 08 1900 (has links)
The purpose of this study is to make an analysis of some factors associated with teacher selection in Texas.
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Quantitative genetics from genome assemblies to neural network aided omics-based prediction of complex traits / Quantitative Genetik von Genomassemblierungen bis zur genomischen Vorhersage von phänotypischen Merkmalen mit Hilfe von künstlichen neuronalen NetzwerkenFreudenthal, Jan Alexander January 2020 (has links) (PDF)
Quantitative genetics is the study of continuously distributed traits and their ge-
netic components. Recent developments in DNA sequencing technologies and
computational systems allow researchers to conduct large scale in silico studies.
However, going from raw DNA reads to genomic prediction of quantitative traits
with the help of neural networks is a long and error-prone process. In the course
of this thesis, many steps involved in this process will be assessed in depth. Chap-
ter 2 will feature a study that compares the landscape of chloroplast genome as-
sembly tools. Chapter 3 will present a software to perform genome-wide associa-
tion studies using modern tools, which allow GWAS-Flow to outperform current
state of the art software packages. Chapter 4 will give an in depth introduc-
tion to machine learning and the nature of quantitative traits and will combine
those to genomic prediction with artificial neural networks and compares the re-
sults to those of algorithms based on linear mixed models. Finally, in Chapter 5
the results from the previous chapters are summarized and used to elucidate the
complex nature of studies concerning quantitative genetics. / Quantitative Genetik beschäftigt sich mit kontinuierlich verteilten Merkmalen und deren genetischer Komponenten. In den letzten Jahren gab es vielfältige Entwicklungen in der Computertechnik und der Genomik, insbesondere der DNA Sequenzierung, was Forschern erlaubt großflächig angelegte in silico Studien durchzuführen. Jedoch ist es ein komplexer Prozess von rohen Sequenzdaten bis zur genomischen Vorhersage mit Hilfe von neuronalen Netzwerken zu kommen. Im Rahmen der vorliegenden Studien werden viele Schritte, die an diesem Prozess beteiligt sind beleuchtet. Kapitel 2 wird einen Vergleich zwischen einer Vielzahl an Werkzeugen zur Assemblierung von Chloroplasten Genomen ziehen. Kapitel 3 stellt eine neu entwickelte Software zur genom-weiten Assoziationskartierung vor, die bisherigen Programmen überlegen ist. Kapitel 4 stellt maschinelles Lernen und die genetischen Komponenten von quantitativen Merkmalen vor und bringt diese im Kontext der genomischen Vorhersagen zusammen. Zum Schluss in Kapitel 5 werden die vorherigen Ergebnisse im Gesamtkontext der quantitativen Genetik erläutert.
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Excessive Parallelism in Protein Evolution of Lake Baikal Amphipod Species FlockBurskaia, Valentina, Naumenko, Sergey, Schelkunov, Mikhail, Bedulina, Daria, Neretina, Tatyana, Kondrashov, Alexey, Yampolsky, Lev, Bazykin, Georgii A. 01 September 2020 (has links)
Repeated emergence of similar adaptations is often explained by parallel evolution of underlying genes. However, evidence of parallel evolution at amino acid level is limited. When the analyzed species are highly divergent, this can be due to epistatic interactions underlying the dynamic nature of the amino acid preferences: The same amino acid substitution may have different phenotypic effects on different genetic backgrounds. Distantly related species also often inhabit radically different environments, which makes the emergence of parallel adaptations less likely. Here, we hypothesize that parallel molecular adaptations are more prevalent between closely related species. We analyze the rate of parallel evolution in genome-size sets of orthologous genes in three groups of species with widely ranging levels of divergence: 46 species of the relatively recent lake Baikal amphipod radiation, a species flock of very closely related cichlids, and a set of significantly more divergent vertebrates. Strikingly, in genes of amphipods, the rate of parallel substitutions at nonsynonymous sites exceeded that at synonymous sites, suggesting rampant selection driving parallel adaptation. At sites of parallel substitutions, the intraspecies polymorphism is low, suggesting that parallelism has been driven by positive selection and is therefore adaptive. By contrast, in cichlids, the rate of nonsynonymous parallel evolution was similar to that at synonymous sites, whereas in vertebrates, this rate was lower than that at synonymous sites, indicating that in these groups of species, parallel substitutions are mainly fixed by drift.
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The Factors that Influence the College Choice of Hispanic College StudentsRanero, Jessica Janet 08 May 1999 (has links)
The United States has undergone a dramatic demographic shift in the last 40 years, particularly in terms of the racial and ethnic composition of the country. Like the other racial and ethnic minority groups, the Hispanic population is also a rapidly increasing segment of the United States. These shifts have affected many of the country's social institutions. For example, primary and secondary education have experienced a dramatic demographic shift in terms of race and ethnicity in the last 20 years.
Higher education has also been affected by demographic shifts in the U.S. Although the numbers of racial and ethnic minorities enrolled in college have increased, that growth has not been proportionate to the changing numbers in the United States' population. For example, in 1990 the census reported over 22 million Hispanics in the U.S., or 9% of the total population, yet the 724,600 Hispanic students enrolled in higher education represented only 6% of all students in college ("College Enrollment,", 1998; "We the Americanâ ¦Hispanics", 1993).
These gaps between Hispanic growth in the general population and Hispanic college enrollment are due to several factors, including the college choice process. Currently, research on Hispanic college choice is limited.
The purpose of this study was to examine the factors that influence the college choice process for Hispanic students. Data were collected by administering the College Choice Survey (CCS), an instrument designed specifically for this study.
A total of 383 surveys were mailed and 144 surveys were completed and returned by respondents. This reflected a response rate of 38%. A total of 65 ANOVAs were run on the data elicited from participants. Five ANOVAs were run on the subscales, which included total College Choice Survey scores, Internal Search scores, Internal Selection scores, External Search scores, and External Selection scores. The dependent variables were gender, generational status, and ethnic background. A total of three significant differences were found among these five ANOVAs.
The remaining 60 ANOVAs examined differences reported by respondents on the last two items in the survey. These items asked participants to rate the degree to which they used sources of support for both the search and selection processes. The ANOVAs were run for differences by main effect only (i.e. gender, generational status, and ethnic background). Results revealed a total of three significant differences on the sources of support participants used during the search process and a total of four significant differences among the sources of support respondents used during the selection process.
In summary, this study was valuable because it contributed to the understanding of the college choice process of Hispanic students. The results of this study revealed both pragmatic and significant differences in the college choice process of Hispanic students by gender, generational status, and ethnic background. Higher education administrators may strive to better understand the differences in the college choice process of Hispanic students and consider these differences in designing recruitment and admissions efforts. / Master of Arts
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Application of Hyper-geometric Hypothesis-based Quantication and Markov Blanket Feature Selection Methods to Generate Signals for Adverse Drug Reaction DetectionZhang, Yi January 2012 (has links)
No description available.
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Vibrotactile Guidance Cues For Target IdentificationDowns, Joshua 01 January 2005 (has links)
The purpose of this dissertation was to establish how vibrotactile guidance cues can be used to improve marksmanship. This work originated in an effort to provide covert communication, navigation, and weapon aiming cues for infantrymen. It is predominantly an application-driven investigation rather than driven a priori by specific theoretical predictions from models of human performance. Three experiments are presented. Experiment 1 established the affect on initial response to vibrotactile guidance cues of tactor placements on the palmer versus dorsal surface of the hand, and targets appearing left versus right of center. Results suggest that tactile cues provided on the left side of the medial line of the hand afford moving the hand to the left, while tactile cues provided on the right side of the medial line afford moving the hand to the right. Experiment 2 established the affect of continuous relative distance cues and on- versus off-target vibrotactile stimuli on reaction time and accuracy for target selection. Results indicated an interaction between the pulse rate of vibrotactile stimuli and the method used to highlight an "on-target" condition; the suppressed target condition was superior to the enhanced target condition when the pulse rate increased as the cursor moved closer to a target. Experiment 3 established if there are performance differences between discrete and continuous distance information for target selection, and investigated the interaction between the near-target pulse rate and on-target cues. Results indicate that maximizing the difference between near-target guidance cues and on-target cues reduces the target selection time, particularly when the near-target pulse rates are fast (ISI = 10 msec). The results also suggest that, as with vision, the vibrotactile off-target guidance cues are not necessary during the whole target selection task. Rather, the guidance cues can be provided only during the initial pop-up condition and during the sub-movements closing on the target.
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