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Vocalization in a Population of Green-Tailed Towhees (Chlorura chlorura)Burr, Timothy Andrus 01 May 1974 (has links)
Studies of vocalizations in a montane population of Green-Tailed Towhees were conducted during the summer months of 1971 and 1972 in Cache County, Utah. The song and call repertoiries of 10 breeding pairs were recorded and analyzed on a sound spectograph.
Males averaged 8.7 different song and 18.2 different not types. Song variation on the population level is high (58 different songs) but the sharing of these songs among the males is low (22.4) . Populational note structure is equally diverse but reveals a greater degree of sharing (75%).
Both males and females used three calss, the meow, tick, and poitt, whereas at least three more, the rattle, tst-tst-tst, and skee-skee-skee, are used only by the female.
Recoginition of the songs of conspecifies apparently is promoted by the distinctive introductory note, the duration of the song and the abruptness of changes within it.
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Patterns of microsatellite and mitochondrial DNA variation among anadromous and freshwater alewife (Alosa pseudoharengus) populations /Kuhn, Kristen Leigh, January 2004 (has links) (PDF)
Thesis (M.S.) in Marine Biology--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 70-79).
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Population Invariance of Linking Functions of Curriculum-Based Measures of Math Problem SolvingHuang, Jia 11 June 2010 (has links)
The purpose of this study was to investigate population invariance of the true-score linking functions with respect to the ability subgroups (i.e., average-achieving students, low-achieving students, and students with learning disabilities). The mean/mean linking functions for five alternate forms of a curriculum-based math problem solving measure were based on the Rasch model. Most studies of curriculum-based measurement have reported only the reliability and validity of alternate forms of measures. This is necessary but insufficient for establishing alternate forms of curriculum-based measures. It is also necessary to establish equivalency of the forms. The present study was based on data from a previous study that developed equivalent forms of curriculum-based measures using Item Response Theory. The participants in the present study were 1,861 seventh- and eighth-grade students. Equatability indices were used to evaluate population invariance of the Rasch mean/mean linking functions over the ability subgroups. Results indicated that the Rasch mean/mean linking functions were population invariant for the ability subgroups across the five alternate forms. The differences between the linking functions computed on the ability subgroups and the linking function on the whole group were negligible for the five forms. Several implications and recommendations for future studies on population invariance of the linking functions with alternate forms of curriculum-based measures were discussed.
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Bat Population Dynamics: An Individual-based Model ApproachFederico, Paula 01 August 2007 (has links)
Temperate zone bats are subject to serious energetic constraints due to their high surface area to volume relations, the cost of temperature regulation, the high metabolic cost of flight, and the seasonality of their resources. To my knowledge, there are no individual-based mathematical models for any bat species. The model developed here for a female bat is primarily based on life history and energetics. It describes the growth of an individual female bat using a system of differential equations modeling the dynamics of two main compartments: storage (lipids) and structure (proteins and carbohydrates). The model is parameterized for the little brown bat, Myotis lucifugus, because of information available on energy budgets and changes in body mass throughout its life history. However, with appropriate modifications the conceptualization might be applied to other species of bats with similar life histories.
The dynamic estimates of daily energy budgets resulting from the model reasonably compare to previous estimates obtained through different methodologies. Sensitivity analysis using statistical screening design techniques identifies the individual parameters driving the model output and indicates the individual characteristics that might play an important role in survival, reproduction, and consequently in population dynamics. The individual model is used to test hypotheses related to strategies used by temperate bats to meet their energy demands. A complete corroboration of the model is not possible due to the lack of a data set independent of that used to construct and calibrate the model.
The individual model is integrated into a structured population model. Characteristics of the individuals determine the structure and, subsequently the dynamics of the population. This methodology uses and integrates the information on bat biology and physiology that has been collected primarily at the individual level. Survival and reproductive rates estimated from simulated populations under varying density dependence are comparable to those reported in the literature for natural populations of M. lucifugus. The population model provides insight into possible regulatory mechanisms of bat population sizes and dynamics of survival and extinction. A better understanding of population dynamics can assist in the development of management techniques and conservation strategies, and to investigate stress effects.
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The Study of Kaohsiung Municipal Government Aged Population Care PolicyZhang, He-yi 21 August 2007 (has links)
According to the definition given by World Health Organization (WHO), if a country¡¦s percentage of people who are older than 65 years old is greater than 7% of total population, it is an aging society. Based on the forecast statistics for the aged population from the Ministry of Interior, Taiwan¡¦s aged population will rise to 14% in 2010 and will be over 20% in 2030. The fast growth of the aged population is a common social phenomenon around the world. Indeed, how to take care of the aged is an important issue, especially in Taiwan.
Purpose: This research aims to understand problems of aging population, such as employment, medical care, care of the aged, long-term care, long-term family support, leisure, and education. The result of the study might serve as a reference for Kaohsiung city government in making caring policies for the aged population.
Material and method: This study is conducted through deep interview and questionnaire. The content focused on Kaohsiung city government¡¦s caring policies for the aged population. 170 subjects received interview and questionnaire. 150 cases were obtained, 20 being excluded due to incomplete data.
Result: (1) 34.7% of the Kaohsiung residents do not have the concept of the care of the aged and only 20% of the 50-to-60-year-old residents¡¦ plan their later life. (2) 30% of the Kaohsiung residents¡¦ first choice is living with their children and their next choice is living in the community (26%). The third choice is living in private nursing centers (18.7%). (3) 60.6% of old people are not willing to live in nursing centers.
Discussion: In Taiwan traditional culture, people believe that the best life of the aged is living with children, playing with grand-children, and then died by nature. From the result of this study, Kaohsiung city government¡¦s caring policies for the aged population will achieve the goal to create a high-quality and peaceful environment.
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Smoking Behaviours Among Pregnant Women in the Baffin Region of NunavutNelson, Chantal 27 September 2012 (has links)
This thesis examined three different research questions to help build a knowledge base for future intervention strategies by better understanding the reasons behind smoking among pregnant women in Nunavut. The first study focused more at the individual level and investigates clinical and socioeconomic factors and their relationship to readiness to quit smoking. The second manuscript moved beyond the individual level to the broader social and structural environment to identify a broader range of barriers and facilitators to smoking and smoking cessation among Inuit women. This second manuscript draws upon in-depth interviews focusing on perceptions of smoking, and perceived barriers and facilitators of smoking behaviours. Finally, the third manuscript investigated the perspectives of health care providers regarding the barriers and facilitators of smoking cessation for pregnant women in the Baffin Region of Nunavut and describes perceptions of smoking cessation resources available to health care providers in the Baffin Region.
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Population studies of <i>Ascochyta rabiei</i> on chickpea in SaskatchewanVail, Sally L 09 May 2005
An epidemic increase in severity and incidence of asochyta blight, caused by Ascochyta rabiei (Pass) Labrousse (teleomorph: <i>Didymella rabiei</i> (Kovachevski) v. Arx. Syn. <i>Mycosphaerella rabiei </i>Kovachevski), has occurred on chickpea (<i>Cicer arietinum</i> L.) crops in Saskatchewan over the past 5 growing seasons. In order to explore the nature of the outbreak, studies assessing population differences in pathogenicity and genetic variability were employed. Isolates of <i>A. rabiei</i> collected in 1998, 2001 and 2002 were inoculated onto 7 differential chickpea genotypes for pathogenicity testing. <p> Significant isolate by differential interaction occurred, but accounted for a low proportion of the total variability suggesting no genotype specific relationship exists between <i>A. rabiei</i> and <i>C. arietinum</i>. Furthermore, it was found that when averaged over all differentials, the isolates from 2001 and 2002 caused significantly greater disease than isolates from 1998, suggesting that the disease epidemic is in part due to a shift in the population to overall greater aggressiveness. The largest increase in disease severity was observed on the cultivar Sanford, which was widely grown in commercial chickpea fields before 1999. To evaluate the genetic diversity of different <i>A. rabiei</i> populations, 30 isolates from 1998 and 30 isolates from 2002 were compared with random amplified polymorphic DNA fingerprinting. Several clusters of isolates collected from either 1998 or 2002 were approximately 60% genetic similar suggesting divergence of these populations of <i>A. rabiei</i>. However, analysis of molecular variance showed that over 90% of the variation occurred within populations. Pairwise differences and gene diversity over loci showed that genetic diversity of the 2 populations had the same amount of genetic variability. Analysis of mating type distributions revealed that the populations from 1998, 2001 and 2002 did not significantly depart from a 1:1 ratio suggesting random mating of each population. Further supporting the hypothesis of a randomly mating population, linkage disequilibrium for both 1998 and 2002 populations was very low.
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Comparison of Canadian and international Angus cattle populations using gene variants and microsatellitesCarruthers, Chelsey Rae 09 November 2009
Seven single nucleotide polymorphisms in six genes (LEP, IGF2, MC1R, PMCH, CAPN1, and CAST) which had been shown to affect traits of economic importance were used to compare the allele frequencies and diversity of a Canadian population of Angus cattle and an International population. Genetic diversity was also measured using 22 microsatellite markers that were assumed not to be affected by selection.<p>
The Canadian population consisted of 107 cows and 57 bulls, while the Canadian Angus Associations International Embryo Program population consisted of 26 calves. Black and red animals were represented in each population. Although the bulls of the Canadian population represent Angus from 16-17 years ago, and the cows of the Canadian population represent Angus from 2006-2007, no difference was observed in either the set of microsatellite genotypes nor the SNP genotypes.<p>
A significant difference was found between the Canadian and International populations at CAST, with the Canadian population exhibiting a higher frequency of the favorable A allele than the International population. This allele is positively correlated with tenderness. No significant differences were found for the other genes. Both populations were in Hardy Weinburg equilibrium for all genes except MC1R, which affects coat color.<p>
Using microsatellites, the total genetic variability of the two Angus populations was measured, showing that 93% of total variability was attributed to differences within, and not between, populations. Randomly chosen cattle could also be assigned to the correct population 97% of the time, based on microsatellite genotypes, and 75% of the time based on SNP genotypes.<p>
Mean heterozygosity was 0.578 based on microsatellites and 0.332 based on SNPs. The proportion of genetic variability between the two populations was 3% based on microsatellites and 7% based on SNPs. It is possible this reflects the results of indirect selection differences in various countries.<p>
Finally, Neis genetic distance was measured between the Canadian and International populations. The Canadian and International populations had a pairwise genetic distance of 0.097. In comparison, the genetic distance of Canadian Angus was 0.135 to Blonde dAquitaine, 0.251 to Simmental, 0.258 to Gelbvieh, 0.281 to Limousin, 0.305 to Holstein, 0.334 to Belgian Blue, and 0.452 to Hereford based on microsatellite markers.<p>
The results of this study show that the Angus breed contains as much or more genetic diversity than other cattle breeds. Greatest genetic differences exist between individual animals, not between populations of cattle in Canada and other countries.
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Isozymic and cytological studies on populations of the introduced bee species, Megachile (Eutricharaea) rotundata and M. (Eutricharaea) apicalisChen, Xiaoshe 28 September 1992 (has links)
Thirteen New World populations of Megachile rotundata and M. apicalis and
two Old World populations of M. rotundata were analyzed at 23 enzyme loci using
cellulose acetate electrophoresis. Conventional and G- or C-banded karyotypes were
also examined in these populations. The principal findings are (1) No differences
were found in the level of heterozygosity between haplodiploid Megachile and that of
other diploid insects. This is the first record showing the mean heterozygosity in the
hymenopteran genus to be consistent with the mean of most other diploid insects. (2)
There was no difference in the level of heterozygosity nor the percent polymorphic
loci between males and females, and heterozygotes was discovered in males of the
two megachilid species studied. (3) The heterozygosity levels among New World
populations of M. rotundata and M. apicalis were similar, but both were more than
twice that of Old World rotundata analyzed. This is consistent with the expectations
of the founder-event models of both Carson and Templeton. (4) FST, the amount of
genetic differentiation among populations, was greater among New World populations
of apicalis sampled than among those of rotundata. The extensive commercialization
in rotundata may have tempered interpopulation differences which might had
occurred had the species been undisturbed. (5) Wrights "isolation by distance" model
is inapplicable to either of the two Megachile species. In rotundata, the high gene
flow level suggests that human commercial action may effectively disrupt any
opportunity for the development of locally adapted populations through selection. In
apicalis, little gene flow is present among the populations which is expected by both
Carson and Templeton models. The absence of any clinal pattern in apicalis probably
better reflects Templeton's transilience model. We believe that the random alteration
of major alleles, implicit in transilience, more readily accounts for the distinct local
populations we found in apicalis. (6) Chromosomal data suggest that both pericentric
inversions and deletions have been involved in karyotype evolution of the two species
and a primitive karyotype is proposed based on its ubiquitousness in all populations of
both species. / Graduation date: 1993
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Population studies of <i>Ascochyta rabiei</i> on chickpea in SaskatchewanVail, Sally L 09 May 2005 (has links)
An epidemic increase in severity and incidence of asochyta blight, caused by Ascochyta rabiei (Pass) Labrousse (teleomorph: <i>Didymella rabiei</i> (Kovachevski) v. Arx. Syn. <i>Mycosphaerella rabiei </i>Kovachevski), has occurred on chickpea (<i>Cicer arietinum</i> L.) crops in Saskatchewan over the past 5 growing seasons. In order to explore the nature of the outbreak, studies assessing population differences in pathogenicity and genetic variability were employed. Isolates of <i>A. rabiei</i> collected in 1998, 2001 and 2002 were inoculated onto 7 differential chickpea genotypes for pathogenicity testing. <p> Significant isolate by differential interaction occurred, but accounted for a low proportion of the total variability suggesting no genotype specific relationship exists between <i>A. rabiei</i> and <i>C. arietinum</i>. Furthermore, it was found that when averaged over all differentials, the isolates from 2001 and 2002 caused significantly greater disease than isolates from 1998, suggesting that the disease epidemic is in part due to a shift in the population to overall greater aggressiveness. The largest increase in disease severity was observed on the cultivar Sanford, which was widely grown in commercial chickpea fields before 1999. To evaluate the genetic diversity of different <i>A. rabiei</i> populations, 30 isolates from 1998 and 30 isolates from 2002 were compared with random amplified polymorphic DNA fingerprinting. Several clusters of isolates collected from either 1998 or 2002 were approximately 60% genetic similar suggesting divergence of these populations of <i>A. rabiei</i>. However, analysis of molecular variance showed that over 90% of the variation occurred within populations. Pairwise differences and gene diversity over loci showed that genetic diversity of the 2 populations had the same amount of genetic variability. Analysis of mating type distributions revealed that the populations from 1998, 2001 and 2002 did not significantly depart from a 1:1 ratio suggesting random mating of each population. Further supporting the hypothesis of a randomly mating population, linkage disequilibrium for both 1998 and 2002 populations was very low.
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