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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Community participation among people who are homeless

Chang, Feng-Hang January 2013 (has links)
Thesis (Sc.D.)--Boston University / Community participation has been regarded as a goal for people with rehabilitation needs, but there is a lack of consensus about the definition and measurement of community participation. In addition, there is limited knowledge about the community participation of individuals who are homeless. This dissertation contains three studies aimed at furthering our understanding about community participation among individuals who are, or were previously, homeless. Study 1 systematically reviewed instruments that measure community participation in people with disabilities and compared these instruments by analyzing the content based on the International Classification of Functioning, Disability and Health Perspective (ICF) classification. Seventeen instruments were identified as containing community participation items. None of these instruments covered the full breadth of community participation domains, but each addressed community participation to some extent. Furthermore, most of the instruments lose precision by treating diverse activities as a single concept. [TRUNCATED] / 2018-09-01
292

Impact of early season insect management decisions on yield of soybean

North, John Hartley 09 August 2019 (has links)
To determine the optimal seeding rate and utilization of seed treatment combinations for maximizing soybean yield within optimal and late planting dates. Also, experiments were conducted to quantify effects of soybean stand loss and to determine optimal seeding rates at various planting dates comparing three seed treatments. Experiments were conducted to test influence of planter type and seeding rate on soybean. Soybean seed treated with at planting insecticides showed no difference in yield compared to fungicide only treated seed. Also, yields were maximized at low seeding rates where no stand loss occurred. Soybean yields benefited from where seeding rates were increased at 20% and 40% stand loss. Higher seeding rates can provide significant risk of yield and economic losses if no stand loss occurs. Optimal plantings can significantly increase soybean yields compared to later plantings. There was a significant difference in yield where fungicide only treated seed was planted compared to seed treated with a neonicotinoid. Low seeding rates maximized yield at optimal planting dates but were penalized at late planting dates. Soybean yields benefited from increased seeding rates at the later planting dates but there was no difference in any of the seed treatments compared to untreated soybean. Also, there was less variation in inter-spacing of plants at the lower seeding rate compared to higher seeding rate when using the cone planter compared to the other planter types. There was no difference in yield for soybean planted with any of the evaluated planter types. Yield differences were observed from higher seeding rate compared to low seeding rate.
293

Population genetics study of the imported fire ants (Formicidae: Solenopsis spp.)

Garlapati, Rajesh Babu 08 August 2009 (has links)
The study was divided into three main sections. In the first section, temporal stability of genetic structure of red imported fire ant populations and effective population sizes were assessed with the help of microsatellites. The second part of the study was focused on the development of new microsatellite markers for the population genetics study of fire ants. The third part of the study was aimed at describing the association of phenotypic and genotypic characters of polygyne hybrid (Solenopsis invicta x richteri) fire ant in a colony and identifying the origin of polygyny in hybrid imported fire ant colony. Meridian, Yazoo City and Crystal Springs in Mississippi and Mobile, Alabama were selected for conducting the study. The overall FST estimates and the pairwise FST estimates between the populations of study, indicated little genetic differentiation and low spatial variation in the nuclear genetic structure of red imported fire ant. Gene flow estimates indicated that there is extensive movement between these populations. From 2006 to 2008 the FST estimates decreased and gene flow estimates increased, indicating that there is no equilibrium between genetic drift and migration in the populations studied. Effective population sizes ranged from 10 -17 in these populations.We have isolated and characterized an additional 11 polymorphic microsatellite loci in the invasive ant S. invicta from a population in Lauderdale County, Mississippi. The observed and effective number of alleles ranged from two to six (average 3.1818 ± S. E. 0.0486). Probability tests indicated significant deviations from the Hardy-Weinberg equilibrium at three loci. The polymorphism information content of the microsatellites ranged from 0.1482 to 0.6208.Identifying multiple inseminated queens in a colony and sequencing the critical region of Gp-9 locus (1600 base pairs) in individuals with the polygyne allele strongly indicate the association of phenotypic and genotypic characters of polygyny in a hybrid imported fire ant colony. A 100% match of Gp-9B and Gp-9b alleles and concordance in the critical amino acid substitutions of the Gp-9 locus in the hybrid fire ant with S. invicta Buren provides the evidence that polygyny in the hybrid imported fire ant colony is derived from S. invicta.
294

Three Essays in Quantitative Analysis

Dong, Zhiyuan 04 October 2010 (has links)
No description available.
295

Extended commuting and non-metropolitan population change : the case of the Columbus, Ohio commuting field /

Maraffa, Thomas Anthony January 1980 (has links)
No description available.
296

Variables affecting public school enrollment change /

Griffith, William J. January 1964 (has links)
No description available.
297

A generalization of the population density gradient concept /

Papageorgiou, G. J. January 1970 (has links)
No description available.
298

Class, race, and ethnicity as factors of residential density /

La Greca, Anthony Joseph January 1973 (has links)
No description available.
299

Studies on HPV Infection and Persistence in a University Undergraduate Population / HPV Infection and Persistence

Bibby, Elisa 09 1900 (has links)
Cervical cancer is preceded by a spectrum of abnormalities in the cervical epithelium. Research supports an etiological role for certain types of human papillomaviruses (HPVs) in cervical pathology. More than 70 HPV genotypes have been characterized based on complete genome sequences and of these, about half infect the genital tract. Genital HPVs are further classified as either "high risk" or "low risk" types based on their association with cervical cancer. The demonstration that there is a relationship between HPV infection and cervical cancer has been dependent on a number of viral nucleic acid-based detection systems such as Southern blot and polymerase chain reaction. However, the lack of methods which discriminate between a specific HPV type and a large number of related HPV genotypes has made studies of disease association difficult. In the first part of this study, a recently developed Amplicor HPV Genotyping Kit was evaluated with respect to its ability to define HPV infection status. The L1 region was directly sequenced from the PCR product in 16 clinical samples to determine which genotype(s) was/were present. Sequencing data from one sample suggested a mixed infection and therefore the PCR product was cloned and sequenced to see if more than one genotype was present. Fifteen out of the sixteen samples sequenced were HPV genotypes which are not represented on the Amplicor Genotyping Kit test strips. The samples are rare HPV types (HPV 61, 62, CP6108 and CP8304). The second part of this study examined the issue of persistence and in particular, I have considered the issue of an appropriate definition of persistence. A number of patients who had evidence of HPV 16 or HPV 18, 6 and 66 were investigated using samples obtained on at least two occasions. Molecular variants of either the LCR gene for HPV 16 or the L1 gene for the other HPV types were studied. No differences in LCR or L1 gene sequence in sequential same patient samples were observed. Two HPV 16 LCR alleles were seen for six patients of which 8/10 showed one nucleotide change at base 7518 and 2/10 were identical to the prototype. Based on a compilation of published studies on HPV 16 variants and subtypes for the long control region, the number of HPV 16 LCR alleles, worldwide, was determined. One HPV 66 and two HPV 18 and HPV 6 L1 alleles were observed. When examining persistence, one must consider the frequency of specific variants (alleles) in the study population. A common variant detected over time could either be a persistent infection or a reinfection with the same viral variant. / Thesis / Master of Science (MS)
300

Ancestry of Modern Indian Populations

Thomson, Aaron 03 1900 (has links)
An analysis of mitochondrial DNA (mtDNA) restriction fragment length polymorphisms (RFLPs) was done with the primary goal of clarifying the relationship of the Indian population to world populations. Phylogenetically informative RFLP sites were amplified, restricted and scored for 187 Indian-descended individuals. This sample collectively represented a geographically wide distribution, the three main religions present in the subcontinent, and three main caste groups. Thirteen haplotypes were found in the Indian population, and when combined with world population data obtained from the literature, 41 different haplotypes were found. India was found to be significantly different from all world populations under study. In agreement with previously reported results, the Indian population was found to be more similar to European populations than south-east Asian populations, with all Indian populations sharing the European-associated haplotypes 14 and 15 at high frequencies. However, high frequencies of haplotype 30 implied similarity with the Evenk population of Siberia, suggesting a possible north-central Asian origin for the Dravidian and/or Indo-Aryan migration into India. Significant geographical differentiation within India was found, with north-western India having significantly higher frequencies of haplotypes 14 and 15 than Southern India, and lower frequencies of the Evenk-associated haplotype 30. The northwest was also significantly more diverse than other regions of India, most likely due to its location on the main routes of repeated migration into India. Significant differences between religious groups were found to have a geographical basis, while caste groups were undifferentiated from each other and the main religious groups. / Thesis / Master of Science (MS)

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