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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.
401

Health in Women of Reproductive Age : A Survey in Rural Zimbabwe

Nilses, Carin January 2000 (has links)
<p>General and reproductive health and reproductive outcome were described in rural women of childbearing age (15-44 years) during 1992-93 in a cross-sectional study in Zimbabwe. Through a two-stage sampling procedure twelve villages were selected at random, and 79% of the women in the villages accepted to participate (n=1213). In a structured interview women¡¯s self-reported morbidity, socio-economic conditions, use of health care and fertility regulation methods, reproductive outcome and infertility problems were assessed. The prevalence rates of anaemia, malaria and syphilis were investigated. Retrospectively, HIV serology was anonymously assessed and associations with socio-economic conditions and morbidity were analysed. </p><p>The mean age was 28 years. Family planning was currently used by 37%. Primary and secondary infertility was reported by 0.9% and 4.4%, respectively. The perinatal mortality rate for all completed pregnancies (n=3601) was 23/1000. During the latest completed pregnancy 94% had attended antenatal care and 85% had delivered in hospitals or clinics. The self-reported complications during delivery seemed to have been cared for within the health care system. </p><p>Women perceived their health as being generally good. Mean haemoglobin (Hb) was 13.5 g/dl and only 3.4% were anaemic (Hb ¡Ü11.0 g/dl). Malaria prevalence was 5.4%, but a positive malaria test was not associated with anaemia. Syphilis prevalence was 2.2%, and a positive syphilis test increased the risk of being HIV positive three-fold (OR=3.0; 95% CI: 1.4-6.2). </p><p>The prevalence of HIV was high (22%). Women aged 15-19 had the lowest prevalence (7.6%), while the highest was found in married women aged 20-29 years (30%). The differences in HIV prevalence between the villages ranged between 8.4% and 33%. HIV positive women reported no more morbidity than HIV negative women. The low morbidity found at the time of the study indicates a fairly short duration of the HIV epidemic. </p>
402

On suicide in European countries : some theoretical, legal and historical views on suicide mortality and its concomitants

Mäkinen, Ilkka January 1997 (has links)
The theme of this thesis is suicide mortality in its various aspects, seen from an international, European perspective. It questions the existence of social (structural) concomitants to suicide mortality and investigates attitudes towards and legislation concerning suicide, as well as some historical processes pertaining to their development. Paper 1 replicates an authoritative study of the "correlates of suicide" on a national level in European countries. It shows that the findings of this study do not hold 16 years later, and it presents some ideas as to why these changes have taken place. It is suggested that there are no simple social correlates to suicide on this level, and that suicide rates tend to vary according to, among other things, international cultural influences. Paper 2 investigates penal legislation relating to suicide in European countries. Three types of punishable action are found: 1) aiding suicide, 2) abetting suicide, and 3) driving somebody to suicide. A majority of European countries include some of these acts in their criminal laws. However, the laws vary very widely between countries, thereby constituting a notable exception to the common presumption of uniformity of law. The scope of the criminalization and the severity of the penalties for the crimes covary both with cultural attitudes towards suicide and with suicide rates. The results are interpreted as indicating the existence of a cultural-normative system, consisting of the cultural attitudes towards suicide, the laws regulating the actions relating to suicide and, perhaps, religion. It influences the occurrence of suicide, mainly by offering individuals cultural models of behavior. Paper 3 describes the process towards the decriminalization of suicide (in 1864) in Sweden, its causes and consequences. It is suggested that the law change took place because of a) the international ideological currents of the time (the heritage of the Enlightenment), b) the examples presented by other European countries, and c) the radical changes in people's behavior. The reform was long overdue, and thus did not have a direct effect on suicide mortality. The increase in Swedish suicide rates in the 19th century is seen as connected with certain aspects of the "modernization" process. Paper 4 addresses the prospects and problems connected with the ap-plication of Talcott Parsons's functionalist theory to suicide research, in particular when contrasting it with Durkheim's theory. It is found that the latter, despite its shortcomings, still dominates socially oriented suicide research. Parsons's theory is seen as implicating the cultural primacy of suicide mortality. Its general usability is, however, highly uncertain since many of its essential constituent parts are not well suited to the subject. A model for suicide rates, consisting of cultural (domestic and inter-national), political, social, diffusion and availability factors is presented. Taken together, the papers constitute a case for cultural (as opposed to socio-structural) research into suicide mortality. They question the repeated testing of structural variables in favor of creating cultural indicators. They suggest some new lines of research, and call for a consistently universal perspective on the problem of suicide and suicide mortality. / <p>Härtill fyra uppsatser.</p>
403

The development of executive function in children exposed to alcohol in utero: An exploratory study.

Badenhorst, Tania. January 2008 (has links)
<p><font face="Times New Roman" size="3"><font face="Times New Roman" size="3"> <p align="left">The study made use of cross-sectional design that compared the performance of younger children (6- to 7-year-olds) with that of older children (12- to 13-year-olds) on various measures of executive function. Within this, it made use of a natural experimental design, with children exposed to alcohol<i><font face="Times New Roman" size="3"> as the experimental group and non-exposed children as the control group.</font></i></p> </font></font></p>
404

Work-related low back pain among clinical nurses in Tanzania.

Mwilila, Mary Chandeu. January 2008 (has links)
<p>Low back pain (LBP) is a significant problem among the nursing population worldwide. Manual lifting and shifting of heavy objects and patients are primary contributing factors. Nurses are supposed to be knowledgeable about the risk factors and preventive measures and effectively apply it into practice to prevent them from sustaining back injuries. Strategies to reducing the incidences of LBP in nurses have been previously implemented but with little outcomes. The purpose of this study was to explore the relationship between occupational risk factors and the prevalence of LBP in nurses at MOI, Tanzania. Therefore, the study examined / the prevalence of LBP amongst nurses, work-related risk factors contributing to LBP, knowledge and effectiveness of back care techniques, and barriers to effective back care techniques in clinical nurses.</p>
405

Smoking behaviour, risk perception and attitude to anti-smoking legislation among students at the University of the Western Cape

Popovac, Masa January 2010 (has links)
The study investigated three aspects related to smoking, namely, smoking behaviour, risk perception and attitudes to anti-smoking legislation. The theoretical framework of the study was the Information-Motivation-Behavioural (IMB) skills model. The study was a quantitative one, making use of a cross-sectional survey design to obtain data about the three variables of interest. Responses to statements about risk perception and attitudes to anti-smoking legislation in the questionnaire were arranged on a three-point Likert scale. The inferential statistics used were one-sample ttests and Chi-square analyses. The results showed an overall smoking prevalence of 16%, with twice as many females than males being smokers in the sample. ‘Coloured’ students in both genders had the highest smoking rate compared to all other race groups. The knowledge of the health risks of smoking were very high, however smokers had a lower perception of risk compared to non-smokers. Moreover, while there was a fair amount of support for anti-smoking legislation among smokers, smokers tended to show less support for legislation than non-smokers, especially to those parts of the legislation that affect them more directly. The results of the study indicate a clear connection between smoking behaviour and the effect it has on both risk perception as well as attitudes to anti-smoking legislation in individuals.
406

Study on the Mechanisms for Corrosion and Hydriding of Zircaloy

Oskarsson, Magnus January 2000 (has links)
This thesis is focused on the mechanisms for corrosion andhydriding of Zircaloy. Special attention is paid tomicrostructural characterisation by cross sectionaltransmission electron microscopy of the oxide layer formed.Three main topics have been treated in this work: (i)Pre-transition oxides were investigated with the purpose ofevaluating if it is possible to predict post-transitionbehaviour of different alloys. (ii) The reason for the commonlyobserved accelerated corrosion of Zircaloy in the presence oflithium hydroxide was investigated by studying the phasetransformation of differently stabilised zirconium oxides andby corrosion studies. (iii) Pre-hydrided Zircaloy-2 was studiedto investigate the influence of hydrogen on the oxidationbehaviour. Characterisation of pre-transition oxides formed onzirconium alloys, has been accomplished with the aim ofdetermining if there are any differences in the properties(morphology, pores, cracks and phases) of the oxide layersformed which might explain the differences in corrosionbehaviour later in life. Four Zircaloy-2 versions and oneZircaloy-4 version were tested in an autoclave at 288° Cfor 20h and 168h and at 360˚C for 96h. Based on thecharacterisation of pre-transition oxide layers only small orno differences were found between the different alloycompositions, thus it is not possible to predict long-timecorrosion behaviour by studying pre-transition oxides. However,large differences were found between the two test temperatures.The higher oxidation temperature results in increased oxidationrates and larger oxide grains, the columnar grains are a factorof 3-4 longer, and the equiaxed grains have an almost doubledmaximum diameter. The fraction of columnar grains andtetragonal phase also increases with temperature. The reasonfor the difference in morphology between the two temperaturesis not fully understood, but the results show that acceleratedtesting at elevated temperatures may be a questionableapproach. One of the Zircaloy-2 samples was also anodicallyoxidised. The oxide layer formed only contains equiaxed grainsand phase analysis shows both monoclinic and tetragonal phasesare present. Oxidation tests of Zircaloy-2 and Zircaloy-4 in water andlithiated water at 360 ° C show that the pre-transitionoxidation rate is not affected by the presence of LiOH, but thetransition occurs earlier and the post-transition oxidationrate is increased. The oxidation rate correlates with thedensity of cracks in the oxide layer and the morphology of theoxide grains. The oxides formed have a layered structure andfor samples oxidised in LiOH solution the inner protectivelayer is thin. The effect of LiOH is suggested to be the resultof partial dissolution of the oxide and subsequentincorporation of lithium ions during adissolution-precipitation process. Newly formed oxide isprobably more hydrous, and the grain boundaries areparticularly liable to dissolution. The increased concentrationof LiOH within cracks and pores could reach the detrimentallevels necessary for dissolution. This is supported by theinsensitivity in the pre-transition region to both thecompositions of the alloy and to the environment. The alloycomposition influences the microstructure of the oxide layer,and thereby the resistance to accelerated corrosion rate inlithiated water. The hydrogen pickup ratio follows the weightgain, not the oxidation rate, up to the second transition. Whenthe protective oxide layer is degraded the hydrogen pickupratio increases markedly. To evaluate if hydrogen is a cause for or a consequence ofaccelerated corrosion, pre-transition oxidation tests ofZircaloy-2 have been performed with hydrogen present in threedifferent states: i) Hydrogen in solid solution in thezirconium alloy, corresponding to the initial oxidation priorto precipitation of hydrides. ii) Uniformly distributedhydrides simulating a situation in whish hydrides starts toprecipitate and iii) Massive surface hydride claimed to be themain cause of accelerated oxidation. Based on the resultsobtained, it is concluded that the oxidation of massivezirconium hydride resembles the oxidation of zirconium metal.This fact clearly shows that accelerated oxidation of zirconiumalloys cannot be due solely to the presence of a massivehydride layer, but also requires a combined effect offorexample interfacial roughness and hydride precipitation. <b>Keywords:</b>Zircaloy, Zirconium alloys, Oxidation, Oxidelayer, Pre-Transition, Hydriding, Pre-Hydrided, Hydrides,Lithium Hydroxide (LiOH), Lithiated Water, Dissolution, CrossSectional TEM
407

Health in Women of Reproductive Age : A Survey in Rural Zimbabwe

Nilses, Carin January 2000 (has links)
General and reproductive health and reproductive outcome were described in rural women of childbearing age (15-44 years) during 1992-93 in a cross-sectional study in Zimbabwe. Through a two-stage sampling procedure twelve villages were selected at random, and 79% of the women in the villages accepted to participate (n=1213). In a structured interview women¡¯s self-reported morbidity, socio-economic conditions, use of health care and fertility regulation methods, reproductive outcome and infertility problems were assessed. The prevalence rates of anaemia, malaria and syphilis were investigated. Retrospectively, HIV serology was anonymously assessed and associations with socio-economic conditions and morbidity were analysed. The mean age was 28 years. Family planning was currently used by 37%. Primary and secondary infertility was reported by 0.9% and 4.4%, respectively. The perinatal mortality rate for all completed pregnancies (n=3601) was 23/1000. During the latest completed pregnancy 94% had attended antenatal care and 85% had delivered in hospitals or clinics. The self-reported complications during delivery seemed to have been cared for within the health care system. Women perceived their health as being generally good. Mean haemoglobin (Hb) was 13.5 g/dl and only 3.4% were anaemic (Hb ¡Ü11.0 g/dl). Malaria prevalence was 5.4%, but a positive malaria test was not associated with anaemia. Syphilis prevalence was 2.2%, and a positive syphilis test increased the risk of being HIV positive three-fold (OR=3.0; 95% CI: 1.4-6.2). The prevalence of HIV was high (22%). Women aged 15-19 had the lowest prevalence (7.6%), while the highest was found in married women aged 20-29 years (30%). The differences in HIV prevalence between the villages ranged between 8.4% and 33%. HIV positive women reported no more morbidity than HIV negative women. The low morbidity found at the time of the study indicates a fairly short duration of the HIV epidemic.
408

Svenska småföretags användning av reserveringar för resultatutjämning och intern finansiering / Swedish small firms’ utilization of allowances for income smoothing and internal financing

Andersson, Håkan A. January 2006 (has links)
Small firms often have inadequate access to the capital necessary for sucessful management. The Swedish Government introduced in the mid-1990s allowance rules that facilitate retention of profit for sole proprietorships and partnership firms. The tax credits arising from the allowances give certain benefits as a source of financing compared to traditional forms of credits. Among the more essential benefits are that the payment for some parts of the tax credit can be put on hold almost indefinitely, or alternatively never be paid. The firms are free to use these means, and the responsibility of future payment of the postponed tax debt stays with the individual firms. The comprehensive purpose of the dissertation may be stated as to increase the understanding of small Swedish firms, especially sole proprietorships, utilizing possibilities for allowances for income smoothing and internal financing. At the beginning the dissertation describes case studies, comprising a smaller selection of microfirms. With a starting-point from the accounted and reported income-tax returns, alternative calculations are made where additional positive tax and finance effects appear possible to obtain. One purpose of these studies is to increase the insight regarding the possibilities of income smoothing and internal financing that arise from utilizing these allowances. These studies also illuminate, to what extent and in what way they are being used in reality. Another objective of these studies is to give a more substantive insight into the technics behind the different allowances, appropriation to positive or negative interest rate allocation appropriation or dissolving of tax allocation reserve appropriation or dissolving of “expansion fund” Theories regarding the creation of resources, through building of capital, and theories on financial planning and strategy are studied. The purpose is to find support for the choice of theoretical grounded underlying independent variables that can be used in cross-sectional studies to explain the use of the possibilities of appropriations. Theories of finance that are of greatest interest, in the operationalisation of these variables, are theories that discuss the choices of different financing alternatives for small firms. The “pecking order theory”, describes the firm’s order of priority when choices of finance alternatives are made. The concept of “financial bootstrapping” expands the frame for different forms of financing choices that especially very small firms have at their disposal. The last part of the theoretical frame deals with the phenomenon of “income smoothing,” which can be translated as leveling out profits/losses. A number of financial and non-financial variables are supported by and operationalised from these financial theories e.g., return on sales, capital turnover, quick ratio and debt-to-equity ratio, respectively age, gender and line of business. Cross-sectional studies are implemented for the taxation years of 1996 and 1999, on databases that have been extracted from Statistics Sweden. The group of 87,276 sole proprietorships included in the study were required to complete tax returns and pay taxes for the business activity according to the supporting schedule, N2, information from the sole proprietorships’ income statement and balance sheet in an accounting statement that comes with the income tax return form. The possibilities of allowances are considered as dependent variables. The intention of the cross-sectional studies is to survey and describe the utilization of possible allowances, with the support of the financial and non-financial independent variables. The connection of these variables to the decision of sole proprietorships to appropriate to the tax allocation reserve is also summarized in a logistic regression model. A number of theoretically based propositions are made for the purpose of observing how the variables are connected to the chances that sole proprietorships actually appropriate to this form of allowance. Appropriation to the tax allocation reserve stands out as the most practiced form of allowance. The studies also clarify that utilization varies among different forms of allowances, but that not all firms that have the prerequisites to utilize the possibilities really do so to the full. A further utilization of the different possibilities of allowances is often conceivable. For the sole proprietorships that are not utilizing these possibilities, the allowances should be considered eligible as a contribution to internal financing and to increase access to capital.
409

Numerical Modeling Of Edremit Geothermal Field

Gunay, Emre 01 September 2012 (has links) (PDF)
The purpose of this study is to examine the geothermal potential, sustainability, and reinjection possibility of Edremit geothermal field. In order to investigate this, a numerical model consisting of a hot and cold water aquifer system is established. A two dimensional cross sectional model is set to simulate this geothermal system. Different pressure and temperature values are applied to the nodes at the boundaries to perform a steady state calibration which minimizes the computed results and observed values obtained from the near well logs. After the calibration, three alternative scenarios are proposed and the response of the pressure and temperature to these conditions is evaluated. At first the water is pumped from the wells of Yagci, Derman, Entur and ED-3 seperately at a mass rate of 5 kg/s and energy rate of 4.182 x 105 J/s. Then, in scenario 2 the water is pumped at the same rate from all the wells mentioned in the first scenario together. For the third scenario another well is opened to the geothermal system and 80% of the pumped water (temperature being 200C) is injected to the system from the wells while all the wells mentioned are working. The results of these scenarios are utilized to evaluate the reservoir in terms of its response to different production and reinjection conditions. Interpretation of the reservoir response in view of the pressure and temperature declines emphasize that such a simulation study can be applied to assess potential and sustainability of the geothermal systems.
410

On the relationship between spinal pain and temporomandibular disorders / Ryggvärk och käkfunktionsstörning : finns det ett samband?

Wiesinger, Birgitta January 2010 (has links)
Both spinal pain and temporomandibular disorders (TMD) commonly occur in the general population. Previous studies demonstrate neurophysiologic and biomechanical couplings between the trigeminal and cervical regions. This investigation tested the null hypothesis of no relationship between spinal pain (neck, shoulder and/or low back) and TMD, by using questionnaires and clinical examinations of the jaw function. In an age- and sex-matched case-control study, the specific aim was to compare the prevalence of signs and symptoms of TMD among cases with long-term spinal pain and controls without spinal pain. The results showed that subjects with spinal pain had signs and symptoms of TMD significantly more often than did controls. The associations remained after excluding all participants with jaw pain. Furthermore, the comorbidity pattern was similar, regardless of location of spinal pain. In a cross-sectional study, the specific aim was to test whether there is a reciprocal cross-sectional dose-response-like relationship between spinal pain and TMD. Two different designs were used, one with frequency/severity of spinal pain as independent variable, and the other, with frequency/severity of TMD symptoms as independent variable. The analysis showed increasing odds for presence of TMD symptoms with increasing frequency/severity of spinal pain, and increasing odds for presence of spinal pain with increasing frequency/severity of TMD symptoms. In a case-control study within a 2-year prospective cohort, the specific aim was to test whether there is a reciprocal temporal relationship between signs and symptoms in trigeminally, and symptoms in spinally, innervated areas. Incidence of symptoms in these areas was analyzed in relation to presence of spinal pain, headaches, and signs and symptoms of TMD at baseline. The main findings were that presence of signs of TMD at baseline increased the onset of spinal pain and symptoms in the trigeminal area, and that spinal pain increased the onset of symptoms in the trigeminal area. An augmentation effect between the significant baseline variables was observed for the incidence of headaches and jaw pain. In conclusion, the investigation demonstrated a cross-sectional and temporal relationship between spinal pain and TMD; thus, the null hypothesis was rejected. The results indicate common pathophysiological mechanisms in the development of spinal pain and TMD. The comorbidity and reciprocal influence that were found call for an integrated and multidimensional approach in the management of individuals with long-term spinal pain and TMD.

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