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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.
321

The Effects of Chronic Alcohol Consumption on Ovarian Function/ Morphology

Roberts, Destiny 01 May 2017 (has links)
Chronic alcohol (ethanol) consumption has been known to affect the major organs of the body and particularly the liver. However, the effects of chronic ethanol consumption on the female reproductive system remain relatively unstudied. A convenient way to study these effects is by analyzing laboratory mice that have been fed an ethanol diet for an extended period of time and comparing them to control mice. In this study, female mice were separated into control and ethanol fed groups. The mice were placed on their specified diets and observed over the course of six weeks. The mice were fed and weighed daily throughout the duration of the experiment. Once a week, vaginal washes were performed on both groups of mice to determine the stage of the estrous cycle for each mouse. At the end of the six weeks, the mice were sacrificed and the ovaries were harvested and fixed in 4% paraformaldehyde. The ovaries were then paraffin embedded and sectioned. Glass microscope slides were then stained using Hematoxylin and Eosin staining procedures for evaluation using standard light microscopy. The tissue’s morphology, follicle development, presence of corpora lutea, and overall appearance were analyzed. Due to the premature deaths of several mice in first group of ethanol fed mice, the experiment was repeated with three more groups of mice to obtain a better representation of data. The data from the control group was compared to that of the ethanol fed group. The mice that received the ethanol fed diet ceased to cycle and arrested in the diestrous phase of the estrous cycle. Our data indicates that the ovarian follicles within the ethanol fed mice show signs of degeneration in the 4b, 5a, 5b, 6, and 7 levels of development. There are also no notable corpora lutea present within the ovaries of the ethanol fed mice. Our findings indicate that chronic alcohol consumption has deleterious effects on ovarian morphology in mice.
322

A role for the CSN/COP9 signalosome in synaptonemal complex assembly and meiotic progression

Brockway, Heather Marie 01 July 2014 (has links)
Defects in meiotic prophase I events, resulting in aneuploidy, are a leading cause of birth defects in humans; however, these are difficult to study in mammalian systems due to their occurrence very early in development. The nematode, Caenorhabditis elegans, is an excellent model for prophase I studies as its gonad is temporally and spatially organized around these meiotic events. Homolog pairing, synapsis, meiotic recombination and crossover formation are essential to the proper segregation of chromosomes into the respective gametes, either the egg or sperm. Disturbances in these events leads to missegregation of chromosomes in the gametes in the meiotic divisions. Synapsis is especially critical in meiosis as it precedes and is required for meiotic recombination in C. elegans. The formation of the synaptonemal complex (SC) is fundamental to chromosomal synapsis, yet the molecular mechanisms of synaptonemal complex morphogenesis are largely unknown. The investigations described in this thesis were undertaken to better understand the molecular contributions to synaptonemal complex morphogenesis. Chapter One reviews knowledge of morphogenesis and its relationship to the events of meiotic prophase I. Recent studies in our laboratory have implicated AKIRIN, a nuclear protein with multiple biological functions, as having a role in synaptonemal complex disassembly, specifically preventing the aggregation of synaptonemal proteins (Clemons et al., 2013). As a result of our efforts to discern the mechanism by which AKIRIN regulates disassembly, we found that the highly conserved CSN/COP9 signalosome has a role in SC assembly, leading to defects in prophase I events and in MAPK signaling , leading to the arrest of nuclei in the later stages of meiosis. While the CSN/COP9 signalosome has been implicated in general fertility in C. elegans (Pintard et al., 2003), no role had been defined in earlier meiotic stages until this study. Chapter Two describes an RNAi enhancer/suppressor screen undertaken in the akir-1 mutant background. Several RNAi clones were selected for future study based on a reduction in brood size; one of which, csn-5/, is the focus of the analysis presented in Chapter 3. Chapter Three describes the phenotypic characterization of two CSN/COP9 signalosome subunits, csn-2 and csn-5. Alleles of both genes display synaptonemal complex protein aggregation and defects in mitotic cell proliferation, homologous chromosome pairing, meiotic recombination and crossover formation, leading to an increase in apoptosis. Oocyte maturation is also disrupted by a lack of MAPK signaling, resulting in a lack of viable oocytes, which renders the csnmutant homozygotes sterile. These findings support a model suggesting the CSN/COP9 signalosome has an essential role in regulating meiotic prophase I events and oocyte maturation. Chapter 4 describes the methodology used in this study. Chapter 5 provides a summary of the thesis findings and examines the future directions to extend this work.
323

Disparities in Access to Contraception in the United States: an Intersectional Analysis

Hammond, Alexandra 01 January 2019 (has links)
An extensive body of research suggests that increasing access to contraception can improve the health of women and children and increase their socioeconomic mobility through increased wages and labor force participation. In the United States, however, contraception and childbearing has historically been used as a form of racist and eugenic population control. This thesis outlines the history of contraception in an intersectional context, inspired largely by the work of Martha Bailey and Dorothy Roberts, from forced childbearing during chattel slavery, to the forced and or coercive sterilization of large populations of Black and Brown women in the modern era. Given the historical racism of contraception, combined with the possibilities for increased socioeconomic mobility and self-determination that accompany increased access to contraception, leads this thesis to ask: who lacks access to contraception in the U.S. today? An original analysis of data from the Guttmacher Center determines that Hispanic women are the most likely to lack access to birth control, followed by younger women and impoverished women. These findings, in conversation with the current implications of the racist past of contraception, imply the need for anti-racist contraception programs that prioritize informed consent and patient autonomy. Such programs could improve women’s and child health, decrease government spending, and contribute to increasing economic and racial equality.
324

Reproductive Allocation and Survival in Grasshoppers: Effects of Resource Availability, Grasshopper Density, and Parasitism

Branson, David Heath 01 May 2001 (has links)
A major challenge in ecology is to understand intraspecific variation in life histories. Variation in resource availability can lead to differences in reproductive allocation and life histories. Grasshoppers are a good organism for the study of variation in life histories, since they exhibit life history plasticity in response to biotic and environmental factors. An optimality model for grasshoppers was developed that predicts optimal total allocation to reproduction and optimal effort-per-offspring as functions of resource availability and mortality. Relative allocation to reproduction is predicted to increase with resource availability, while relative allocation to survival declines. A resource-based trade-off between egg size and number does not exist, as optimal egg size is predicted to be independent of resource intake. I examined if changes in reproductive allocation and survival of Melanoplus sanguinipes (Fabricus) under a range of resource availabilities fit the predictions of the model. The patterns of reproductive allocation and survival in the field were in qualitative agreement with the predictions. I examined the importance of density, resources, and parasitism on the life history patterns of grasshoppers. I conducted an experiment to examine if differences in reproductive allocation of M. sanguinipes are primarily explained by exploitative competition. Per capita resource availability explained a significant amount of the variation in reproduction , as expected with exploitative competition. M. sanguinpes grasshoppers appeared to trade off resource allocation to reproduction for that of allocation to survival, because per capita resource availability did not affect survival. Careful examinations of changes in life history characteristics in response to parasitism are lacking, despite the fact that parasites often influence resource availability for the host. I investigated the effects of a grasshopper ectoparasitic mite on grasshopper reproduction and survival. Mites had small effects on grasshopper survival. As predicted, both species had reduced initial and total reproduction, and completed development of a lower percentage of ovarioles initiated when parasitized. These experiments act to expand our knowledge of life history theory and further our understanding of grasshopper life history variation and population fluctuations.
325

Negotiating and Constructing Place: African Immigrant and Refugee Women’s Experiences Seeking Reproductive Health Information, Services and Support

Greenwood, Heather Louise January 2017 (has links)
African immigrant women and refugee women face disproportionate reproductive health risks and adverse outcomes compared with the Canadian population. The diversity of African women and complexity of the migration process suggest the need for contextualized knowledge to better understand these challenges. I sought such knowledge through the use of the theoretical frameworks of place and intersectionality. These frameworks draw attention to the multi-level mixture of social relations in given contexts and how they create opportunities and oppression. The specific purpose of this research was to: a) explore how the reproductive health experiences of African immigrant and refugee women were shaped by the unique context of given places; b) consider how these women actively negotiated and constructed place in their search for reproductive health information, services, and support. A multiple case study was used to explore the reproductive health experiences of African immigrant and refugee women in three different areas of Ottawa, Ontario. These areas provided different local contexts (e.g., history, socioeconomic profile, proximity to downtown). In each area, data was collected through interviews with African immigrant and refugee women, interviews and focus groups with reproductive health service providers, and mapping of available services. In total, 19 immigrant and refugee women and 23 service providers participated in this study. The findings showed that African immigrant and refugee women’s reproductive health experiences were much more complicated than simple interaction with neighbourhood services. Their varied social positions in Canadian society were highly relevant. In addition, social networks based in places outside of the system (e.g., private homes, religious institutions) were environments in which they were comfortable and sought support for their reproductive health needs. Recommendations based on these findings include the need to engage communities and explore the delivery of information and services outside of the traditional places employed by the Canadian health care system.
326

The Quite Revolution: An analysis of the change toward below-replacement-level fertility in Addis Ababa

Kinfu Ashagrea, Yohannes, yohannes@coombs.anu.edu.au January 2001 (has links)
Rural-urban differentials in fertility behaviour are neither new nor surprising, but a difference of over four children per woman as observed between rural Ethiopia and the country's national capital, Addis Ababa, in 1990 is rare, possibly unique. Reported fertility in Addis Ababa in 1990 was about 2.6 children per woman. By the mid-1990s, it declined further to 1.8 children per woman. This study investigates the dimensions, components and causes of this remarkable reproductive change. ¶ The study specifically asks and seeks to answer the following questions. Is the decline real, or is it merely an illusion created by faulty reporting? If it is real, how has it come about? Did it result from a change in the onset of reproduction or a decline in the proportion of women reaching high parities or both? And in what context has such a fundamental, even revolutionary, change taken place in a country and a continent that are mostly yet to join the global transition to a small family-size norm. ¶ Data for the study were drawn from two national population censuses, undertaken in 1984 and 1994, two fertility surveys, conducted in 1990 and 1995, and a number of supplementary sources, including a qualitative study conducted by the investigator. Results from the study confirm that the trend of declining fertility and the recent fall to below-replacement-level are indeed real. As the analysis shows the decline was largely driven by changes in the marriage pattern, and supplemented by the increased propensity of fertility control observed across all birth orders and age groups. All socio-economic groups in the city have had a decline in cohort fertility and this was brought about both by shifts in population composition (a composition effect) and increased intensity of fertility control within each group (a rate effect). The institutional and cultural factors that are believed to have prompted these changes are discussed in the thesis in some detail.
327

A study of baby boomer women and their expectations of menopause

Jackson, Barbara Ann, n/a January 1996 (has links)
This is a study of a generation of women who are about to enter the climacteric period of their life, the menopause. Born between the years 1946 and 1956 they have been the object of continuous scrutiny by various interest groups. Because they are seen to be unique, many acronyms and titles, the most noted being the 'Baby Boomers' have been attached to them. The women of this generation have been classed as a Very active' generation, leaving a clear mark on society and the re-emerging women's movement. As they near menopause they are approaching a stage that could be seen as their last reproductive transition. For many women there is no cultural ritual, nor a single story to guide them through this period They are however not without advice. The 'big voices' of the drug companies, the medical system and the media, all tender their guidance as the dominant voice. These women have been told what to do by experts throughout their whole lives. It seems 'expert advice' on their reproductive phases have been penned mostly by men in the interests of treating, controlling and saving them. Control of their body remains a key struggle, both physically and linguistically. The purpose of the research was to study the expectations of this post-war, Baby Boom generation of menopause. The study shows that some women have made decisions to embrace non-medical help and accept menopause as an inevitable transition, while others are willing to consider medical help to enhance their 'quality of life '. Believing it is time to look after themselves, it seems many women will take a pragmatic view and accept medical opinion that the menopause is a deficiency disease, even if this requires them to become part of the consumer driven/drug company push for a 'symptom free' menopause. They wish to remain untroubled and express a willingness to do whatever they need to fulfil this. Their fervent hope is that the menopause will not upset their career, family or 'life'. Consequently a large majority of these women will think about or actively pursue hormone replacement therapy.
328

Analyse de protéines spermatiques post-testiculaires et developpement d'outils pour le contrôle de la fertilité de différents mammifères ; Equus caballus, Bos taurus, Arvicola terrestris Scherman

Grignard, Elise 07 October 2005 (has links) (PDF)
Ce travail a consisté en l'étude de protéines de spermatozoïdes de différentes, avec l'objectif de contrôler leur pouvoir fécondant. Dans un premier temps une protéine antioxydante du tractus génital mâle, et acquise au cours de la maturation épididymaire, la glutathion peroxydase 5 (GPX5), a été étudiée dans deux espèces d'intérêt agronomique : l'étalon et le taureau. Les semences de ces animaux sont fréquemment conservées pour des inséminations artificielles. Or lors de la conservation, les spermatozoïdes subissent entre autres un stress oxydant. L'ajout de cette protéine antioxydante dans le milieu de conservation pourrait limiter les dommages subis par les spermatozoïdes. Les séquences spécifiques de cette protéine dans chaque espèce ont été obtenues. Les ARNm ont ensuite été localisés dans les canaux efférents et la tête de l'épididyme équine, ainsi que dans la tête et le corps de l'epididyme bovin. Par ailleurs la protéine bovine a été localisée dans la tête et le corps epididymaire. La seconde partie de ce travail a consisté a analyser les antigènes spermatiques spécifiques d'un rongeur fouisseur , le campagnol terrestre Arvicola terrestris Scherman dans le but de les utiliser pour une immunocontraception de cet animal nuisible. La détermination de protéines spermatiques suscepyibles d'être immunogènes a été entreprise.
329

Kvinnors alkoholkonsumtion före och under graviditeten : Förekomst och prevention. En litteraturstudie

Nilsson, Flavia January 2009 (has links)
<p><strong>Syftet</strong> med denna litteraturstudie var att beskriva kvinnors alkoholkonsumtion före och under graviditeten samt undersöka prevalensen, informationen som gravida kvinnor får av vårdpersonalen och problemhanteringen på mödravården. <strong>Metoden</strong> var en litteraturstudie av vetenskapliga artiklar från åren 1997-2008. <strong>Resultatet </strong>visade att prevalensen av alkoholkonsumtion nådde siffror över 50 % före respektive 20 % under graviditeten. I studierna observerades hög konsumtion under både perikonceptional perioden och första trimestern. Speciellt vanligt var det med berusningsdrickande tidigt i graviditeten. Kvinnor som drack under graviditeten visade sig vara äldre, väl utbildade, rökare och alkoholkonsumenter redan innan graviditeten. Mödravården identifierade inte alla gravida kvinnor som använde alkohol. Screeningsinstrument var nödvändiga för att identifiera och då kunna erbjuda hjälp till denna grupp.</p><p><strong>Konklusion</strong>: I Sverige observerades en positiv tendens med minskat drickande under graviditeten men andelen gravida kvinnor som nyttjade alkohol var fortfarande stor. Problemet var dock fortfarande stort i många andra länder.</p><p><strong>Nyckelord: </strong>alkoholkonsumtion, graviditet, mödravård, screeningstest.</p>
330

Testning för sexuellt överförbara infektioner efter oskyddat oralsex : Personalens attityd och kunskap

Eriksson, Ewa, Olovsson, Anna-Lotta January 2009 (has links)
<p><strong>Aim </strong>The aim of this study was to investigate the attitudes of midwives and gynaecologists at youth health clinics about their own thoughts of risks with unprotected oral sex and testing of orally contagious sexually transmitted infections (STI). The aim was also to investigate the level of knowledge of oral STIs. One further aim was to examine what they thought about the level of knowledge about oral STIs among adolescents and how common unprotected oral sex is within this group and if oral STIs/oral sex is brought up in the form of information or questions during STI-testing.</p><p><strong>Method </strong>Seventy-five youth health clinics all over Sweden were randomly chosen. A questionnaire was sent by mail to the clinics. It included questions about attitudes, knowledge about STIs and information exchange. A midwife or a gynaecologist was asked to fill out the questionnaire. The answers were analysed in the statistical programme SPSS.</p><p><strong>Results </strong>The percentage of answers was 76 % (57/75).  One third of the clinics had guidelines for oral STI-testing. Those clinics were more often testing for oral STIs, informing and asking adolescents about oral STIs. Seventy-nine percent responded that they always or sometimes informed adolescents who were tested for STIs about risks with unprotected oral sex. Almost everyone thought that the knowledge about oral STIs was insufficient among health care staff.  Staff working at clinics with guidelines more often thought that they had sufficient knowledge about oral STIs than those without guidelines. All respondents thought unprotected oral sex was common among adolescents. Eight out of ten were in favor of oral STI-testing being performed more often. The overall attitude was that adolescents should be given more information of the risks of STIs when practising unprotected oral sex. <strong></strong></p><p><strong>Conclusions </strong>Practise of unprotected oral sex involves a risk of transmission of oral STIs. Youth health clinics need to be more actively informing adolescents about it. There is a lack of national guidelines for testing of STIs in Sweden. The majority of youth health clinics did not have any local guidelines for oral STI-testing. Guidelines on oral STI-testing are needed for achieving a more evidence-based care in testing and informing about oral STIs.</p><p><strong>Keywords; </strong>Oral sex, STI, testing, midwives, attitudes.</p>

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