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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.
111

Kin recognition and mate choice in the freshwater snail, Biomphalaria glabrata

Vernon, Jennifer G. January 1993 (has links)
No description available.
112

Parasites, sex and genetic variation in a model metapopulation

Judson, Olivia P. January 1994 (has links)
No description available.
113

Fertility and labour in Rufiji District, Tanzania

Lockwood, Matthew January 1989 (has links)
No description available.
114

Factors affecting contraceptive use among young people in KwaZulu-Natal.

Naidoo, Hyacinthia. January 2005 (has links)
Although sexual and reproductive health practices among young people are well documented, little is known about the factors that affect their decisions to use contraception. This is of paramount importance particularly in KwaZulu-Natal for two reasons: 1) the increasing number of teenage unplanned pregnancies in KwaZulu-Natal and 2) the inherent implication that unprotected sex can result in the transmission of diseases like sexually transmitted infections, including HIV and AIDS. Additionally, the sexual risk-taking and reproductive health behaviour of young people in KwaZulu-Natal is of extreme interest to researchers and program implementers, particularly since KwaZulu-Natal is the worst HIV affected region in South Africa (World Aids Conference XID, 1999). The aim of this study is to investigate sexual and reproductive health practices and dynamics among males and females between the ages 14 and 22 years in two areas in KwaZulu-Natal, South Africa: Metropolitan Durban and the magisterial district of Mtuzini. It explores a selection of the factors that affect contraceptive use among young people. These include age, race, sex, geographic location, relationship status and perceived risk. The study includes a rural-urban comparison, using focus group discussions and structured interviews from a pre-existing data set. Results were analysed using the Statistical Package for the Social Sciences (SPSS). The method of triangulation was adopted as this offered a more holistic approach to the analysis of both the qualitative and quantitative components of this study. The quantitative analysis was conducted using univariate frequencies, bivariate cross tabulations and multivariate logistic regression. The major [mdings of this study were that there is a strong correlation between contraceptive use and relationship status, age and sex of respondent and geographic location: (i) Both men and women in a steady relationship were more likely to use contraception, with a greater prevalence among those young adults who had previously given birth or fathered a child. (ii) respondents in the 20-22 year old age category exhibited the highest occurrence of safe sex practices, (iii) young women viewed contraception more positively than young men; particularly as a means to avoid or delay pregnancy, (iv) knowledge about contraception, its use and source of supply among both men and women between the ages 14 and 22 years is universal, with almost all having heard of at least one modem method of contraception. However, young people living in urban areas displayed a greater knowledge of the different contraceptive methods, than their rural counterparts. / Thesis (M.A.)-University of KwaZulu-Natal, 2005.
115

Geographical variation and population biology in wild Theobroma cacao

Allen, J. B. January 1988 (has links)
No description available.
116

Thermoregulation and population dynamics in Vespa (Hymenoptera: Vespidea)

Martin, Stephen John January 1989 (has links)
No description available.
117

The molecular characterisation of Haemophilus influenzae

Leaves, Nicholas I. January 1995 (has links)
No description available.
118

Spatial distribution of neutral & adaptive genetic diversity in populations of the palmate newt, Lissotriton helveticus

Murray-Dickson, Gillian January 2011 (has links)
Conservation genetics theory predicts that isolated populations on the periphery of a species range will display reduced levels of genetic diversity compared to those more centrally located. Low levels of diversity can potentially compromise individual fitness and population viability among peripheral populations and so from a conservation perspective, understanding genetic structure among populations with low levels of diversity is a priority. Here I examine the levels and spatial distribution of both neutral and adaptive DNA polymorphisms across populations of the palmate newt (Lissotriton helveticus); including both island and mainland populations at the northern extent of their distribution and putative source populations from which postglacial expansion occurred. Five different classes of molecular marker were assayed: (1) mitochondrial DNA sequence variation, (2) micro satellite length variation, (3) MHC allelic diversity, (4) AFLP profiling and (5) candidate nuclear locus (sodium-calcium exchanger) allelic diversity, with an overall prediction that neutral markers will exhibit reducing diversity with increasing latitude and then from mainland to island; and that neutral diversity will be a poor predictor for adaptive diversity given the additional effects of selection on these genes. These predictions were not wholly confirmed. Mitochondrial data demonstrated that refugial populations harboured more genetic diversity than postglacial populations. Conversely, micro satellite diversity did not decline gradually with increasing latitude and insular populations were not necessarily depauperate compared to those on the mainland. Adaptive diversity was not reduced among peripheral or island populations but a signature of directional selection was detected. Lastly, genome-wide AFLP diversity was not reduced among island populations whilst no clear inference was possible from the sodium-calcium exchanger gene. There was a lack of concurrence between neutral and adaptive markers and the results are discussed in relation to the effects of micro-evolutionary processes acting in populations of varying size and isolation. The significance of these findings is discussed in relation to the long term conservation of palmate newt populations.
119

The impact of an alien piscivore the zander (Stizostedion lucioperca (L.)) on a freshwater fish community

Kell, L. T. January 1985 (has links)
No description available.
120

The Effectiveness of Writing Therapy with a General Psychiatric Population

Mappes, Donald C. 05 1900 (has links)
The purpose of this study was to assess empirically the effectiveness of writing therapy with patients in a psychiatric hospital.

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