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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.
41

Versuch einer bevölkerungslehre ausgehend von einer kritik des Malthus'schen bevölkerungsprincips ...

Fetter, Frank A. January 1894 (has links)
Inaugural-dissertation ... Halle-Wittenberg. / Vita. Includes bibliography.
42

Population a study in Malthusianism,

Thompson, Warren Simpson, January 1915 (has links)
Thesis (Ph. D.)--Columbia University, 1915. / Vita. Published also as Studies in history, economics and public law, ed. by the Faculty of Political Science of Columbia University, vol. LXIII, no. 3; whole no. 153. Bibliography: p. 214-216.
43

Early career alienation and socioeconomic attainments of a rural population

Otto, Luther B. January 1973 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
44

Linear and nonlinear deterministic character-dependent models with time delay in population dynamics

Castillo-Chávez, Carlos. January 1984 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 115-122).
45

Evolving populations mathematical analysis of some dynamical properties /

Gimelfarb, Alexander. January 1979 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
46

Thermonukleares Brennen und Mischen mit einer zeitabhängigen Konvektionstheorie in massereichen Population-III-Sternen

Straka, Christian W. January 2002 (has links) (PDF)
Heidelberg, Universiẗat, Diss., 2002.
47

Of moths and candle flames : the aesthetics of fertility and childbearing in the northern areas of Pakistan

Collins, Teresa Mary Helen January 1997 (has links)
No description available.
48

Relationship of population characteristics and development problems : greater Soekmekaar overview (Northern Province)

Masipa, Makgoshi Prescilla January 2001 (has links)
Thesis (M. Dev.) -- University of the North, 2001 / Refer to document
49

Mediators of Fine-Scale Population Genetic Structure in the Black Blow Fly, Phormia regina (Meigen) (Diptera: Calliphoridae)

Charity Grace Owings (7023467) 16 October 2019 (has links)
Population genetic structure is difficult to assess in blow flies (Diptera: Calliphoridae) due to high connectivity and genetic diversity of subpopulations. Previous studies revealed high relatedness among individuals within wild samples of blow fly populations, however broad geographic structure was absent. The aim of this research was to determine if blow fly genetic structure exists at a fine spatiotemporal resolution and, if so, to elucidate the influence of environmental factors and resource availability on fly genetics. Specifically, blow fly population genetic patterns were tested against anull hypothesis that flies adhere to a patchy population model with high genetic diversity (i.e. no structure) and high resource availability. Samples of the black blow fly, <i>Phormia regina</i> Meigen (Diptera: Calliphoridae), were collected at six urban parks in Indiana, USA (=urban) in 2016 and 2017 (N = 14 and 16 timepoints, respectively). Additional sampling in different ecoregions was performed to determine if trends observed at a high-resolution scale were also present at a broad geographic scale. Therefore, <i>P. regina</i> were also collected at four sites within two national parks (the Great Smoky Mountains and Yellowstone National Parks) over a three-day period. Randomly selected females (N = 10) from each sample underwent the following analyses: 1) gut DNA extraction, 2) molecular analysis at 6 microsatellite loci, 3) vertebrate-specific 12S and 16S rRNA sequencing, and, 4) vertebrate fecal metabolite screening. Flies from the national parks and a comparable subset of urban data also underwent stable isotopeanalysis (SIA) to determine larval food source. Overall, strong seasonal population genetic structure was observed over both years in the urban environment (2016 F’<sub>ST</sub>= 0.47, 2017 F’<sub>ST</sub>0.34), however spatial structure was lacking, as seen in previous studies (2016 F’<sub>ST</sub>= 0.04, 2017 F’<sub>ST</sub>0.03). Weather conditions prior to and on the day of blow fly collections, interspecific competition, and resource availability greatly impacted the genetic diversity and kinship of <i>P. regina</i>. A total of 17 and 19 vertebrate species were detected by flies in 2016 and 2017, respectively, and many flies tested positive for vertebrate feces, suggesting that many varied resources are important for maintaining high gene flow among geographic locations. Genetic diversity was non-existent in flies collected from the Smokies (F’<sub>ST</sub>= 0.00), while very slight spatial structure existed in the Yellowstone populations (F’<sub>ST</sub>= 0.07). Environmental factors such as temperature, humidity, and wind speed were all statistically relevant in maximizing fly collections with vertebrate resources. In 720 min of total sampling time in the national parks and a subset of urban data, 28 vertebrate species were identified, and fecal resources appeared to be the most abundant in Yellowstone. Stable isotopeanalysis revealed a majority of larval resources in the national parks were herbivores, with a more even distribution of carnivore and herbivore carcasses present in the urban environment, which likely explains the high genetic diversity of adult flies in these regions. Overall, the null hypothesis that <i>P. regina</i> adheres to a patchy population model could not be rejected for the Smokies populations. However, the urban and Yellowstone populations appear to adhere to a Levins metapopulation model in which variable availability in resources leads to random bottleneck events in the local populations. Overall, environmental conditions, competition, and resource availability are all important factors influencing <i>P. regina </i>population genetic structure in different environments.
50

La transformation de la population active des différents secteurs d'activités économiques au Canada : 1961 a 1981 /

Monette, Josée, January 1993 (has links)
Mémoire (M.E.S.R)-- Université du Québec à Chicoutimi, 1993. / Document électronique également accessible en format PDF. CaQCU

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