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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.
241

Détection de la transition démographique agricole en Chine : sur le plateau de Lœss et dans la plaine du fleuve Yangszé / Detection of the Agricultural demographic transition in China : on the Loess Plateau and in the Yangtze plain / 中国农业起源时期人口变迁研究 (以黄土高原和长江中下游平原地区为例)

Li, Jun 11 June 2015 (has links)
Cette thèse étudie le processus du changement démographique pendant la transition des chasseurs-collecteurs aux agriculteurs sur le plateau de Lœss, qui est la région de l’origine du millet cultivé, et dans la plaine du fleuve Yangszé, qui est la région de l’origine du riz cultivé en Chine. Ce travail de recherche doctoral collecte et analyse les données paléoanthropologiques des nécropoles des deux régions en Chine, et un signal similaire est détecté. Les données archéologiques, comme la densité des sites et la densité des dates au radiocarbone, sont aussi collectées et analysées, pour vérifier ce signal démographique en Chine. Suit à notre étude, nous représentons le contexte environnemental du signal de la TDA, incluant le changement climatique et la variation du paysage. L’amélioration de l’environnement naturel pendant la transition démographique est évidente, mais elle n’est pas une cause décisive de la TDA. Ensuite, nous représentons le changement de la stratégie de subsistance de la population du Paléolithique supérieur au Néolithique dans les deux régions, et son lien de causalité réciproque avec la transition démographique. Les données archéologiques montrent que la transition démographique et le changement de la stratégie de subsistance sont suivis de façon évidente par une modification de l’habitation, et l’arrangement des villages s'est modifié graduellement aussi au fil du temps. Celles-là indiquent probablement que l’augmentation de la taille de population est une cause importante de l’évolution sociale. / In this thesis, we study the process of the demographic change during the transition from the hunters-gatherers to the farmers on the Loess Plateau, which is the region of the origin of the cultivated millet, and in the Yangtze Plain, which is the region of the origin of the cultivated rice, in China. By collecting and analyzing the paleoanthropological data from the cemeteries of prehistorical hunters-gatherers and farmers of these two regions in China, we detect a similar signal of the ADT. This signal is also confirmed by the archaeological data, such as the density of the archaeological sites and the density of the radiocarbon dates. We represent the environmental context of the signal demographic in the following study, including the climatic change and the variation of le landscape. The improvement of the natural environment during the demographic transition is obvious, but it seems that this improvement is not a factor decisive of the ADT. Then we represent the change of subsistence strategy of the population from upper Paleolithic to Neolithic in the two regions, and its relationship of reciprocal causation with the demographic transition. The archaeological data indicate that the demographic transition and the change of the subsistence strategy were evidently followed by the modification of the habitation, and the arrangement of the villages have also varied overtime. These information probably suggest that the augmentation of the size of population is one of the main causes of the social evolution.
242

The comparative demography of invasive plants

Jelbert, K. January 2018 (has links)
Biodiversity, ecosystems, industry and human health are threatened by invasive plant species. The costs of mitigating damages run into billions of pounds per annum. Fundamental to the control of invasive plant species is an ability to predict which species will become invasive. Yet identification of predictive differences between invasive and non-invasive species has proven difficult to pinpoint. In this thesis I identify several weaknesses within published literature, and using field experiments and meta-analyses we address these to find consistent predictors of invasiveness amongst plants. Specifically, I recognize that predictors of invasiveness can be identified by studying plant species in the native range because species may undergo phenotypic and demographic changes following naturalization (Chapters 2 – 5). I also recognize the importance of comparing globally invasive and non-invasive species, and the importance of accounting for phylogenetic relationships so as not to inflate or conceal differences (Chapters 2 – 4). Finally, I investigate whether particular analyses are more appropriate for investigating life history and demographic differences (Chapter 5). This thesis comprises an introductory chapter (Chapter 1), four data chapters (Chapters 2 - 5) and a general discussion (Chapter 6). Chapters 2 and 3 compare life history traits of plant species known to be invasive elsewhere, with their exported but non-invasive sympatric relatives in the native range. Chapter 4 utilizes Population Projection Matrices held within the COMPADRE Plant Matrix Database, to compare demographic projections of stable and transient dynamics of invasive and non-invasive plants; and Chapter 5 compares ten metrics, derived from Population Projection Matrices, of seven invasive species between the native and invaded range to determine if there are demographic or life history differences that facilitate invasion, and to identify those analyses that are most likely to reveal such differences. I find reproductive capacity to be a predictor of invasiveness, and that analyses of transient dynamics are more likely than analyses of projected stable dynamics to reveal demographic or life history differences between invasive and non-invasive species or populations of plants. I discuss these findings in the context of invasive risk assessment protocols and highlight future research opportunities.
243

The disease-scape of the new millennium : a review of global health advocacy and its application

Mableson, Hayley Elizabeth January 2014 (has links)
The global disease scape is constantly shifting, influenced by demographic transitions, altering the balance of the burden of infectious and non‐communicable diseases. The epidemiological transitions can be divided into three stages: the first, an increase in infectious disease burden as populations settled, then grew into towns and cities providing conditions for infectious agents to maintain spread; the second transition follows industrialisation, changes in lifestyle, diet and improved sanitation whereby infectious diseases are reduced and non‐communicable disease (NCD) prevalence increases; the third transition describes the re‐emergence of infectious diseases as the AIDS epidemic and other emerging and re‐emerging disease outbreaks lead to an increasing burden of infectious diseases, particularly in developing countries. Analysis of the disease‐scape has been carried out using WHO Global Burden of Disease data and correlation to demographic factors calculated using World Bank Development Indicators. The balance of chronic NCDs and infectious diseases can be represented numerically as the unit rate of infectious to non‐communicable diseases. The rate, which indicates at which end the continuum lies can then be correlated to these demographic development indicators to assess the factors which are influential to the continuum. As the balance of infectious and non‐communicable diseases around the world alters, the focus of the advocacy at the global health level has been examined to assess if the trends follow that of the shifting continuum. This has been carried out through an assessment of the WHO World Health Assembly (WHA) resolutions adopted annually between 1948 and 2013 on the subject of infectious and/or non-communicable diseases. The principle of International health stemmed from the need to contain the international spread of communicable diseases, so it is not surprising that in the first decade of the WHO, 88% of the resolutions adopted for infectious and non‐communicable disease were adopted for infectious diseases. In the latest ten years of the WHO, 72% of the Assembly resolutions for infectious and non‐communicable diseases were focused on infectious diseases; this indicates that while there has been a shift in the balance, the adopted resolutions still focus heavily on infectious diseases. An example of how advocacy can elevate diseases to a higher position on the global health agenda is that of the Neglected Tropical Diseases. Following the Millennium Development Goals, this group of seventeen diseases has been highlighted as being “neglected” in terms of funding, research and political will. A review of the campaign to highlight this shows how global health advocacy can elevate diseases to a prominent position on the global health agenda. With this in mind, the advocacy for a sub‐group of Neglected Zoonotic Diseases has been examined at the WHA level. The results highlight the sporadic nature of support to control these diseases, and that activism for control of some of the major zoonotic diseases remains lacking. Rabies is explored as an example of a disease for which there are recommendations and support at the global level for the control and elimination of the disease, but for which barriers to control exist locally in endemic countries. The advocacy for diseases at the global health level has the possibility to impact the priorities of health care within individual nations. However the advocacy at this level may take time to reflect the changes within the disease‐scape. The impact of such advocacy is also limited by local political will, availability of resources and local cultural implications. Therefore there is a need to ensure that efforts to control diseases are tailored to specific populations and that resources are made available to support the advocacy.
244

Analýza penzijních systémů vybraných zemí EU / Analysis of pension systems of chosen EU countries

Polický, Martin January 2011 (has links)
This thesis deals with analysis of pensions system of European Union with the focus on demographic development and situation on labour market. It deals with historic development of pension systems and various classifications of these systems. Consequently, it looks into theoretical advantages of PAYG systems and fund-schemes in terms of demographic development and labour market. In the empirical part, this thesis analyzes choosen pension scheme of European Union in the criteria of social security, financial sustainability and microeconomic efficiency. The results of the analysis imply that the Netherlands' pension scheme might be the best, because it performed well in all criteria. The work is then trying to answer the question, whether the fund-scheme is better than PAYG system when it comes to meeting the challenges of ageing population. This thesis finds little evidence that the fund-scheme could cope better with the challenges than the PAYG system and therefore this thesis concludes that fund-scheme is not a solution to the demographic development.
245

Důchodová reforma v České republice / The Pension Reform in the Czech Republic

Drýk, Martin January 2011 (has links)
The Pension system in the Czech Republic seems to be financialy unsustainable because of demographic development and economic consequences which is why it requires detailed systemathic change. This thesis will, in theory, describe and analyze reform possibilities which are derived primarily from conclusions of the Bezděk comission. At the same time it will also focus on alternatives which are presented by political parties or which are known from experiences from abroad. This thesis will also mention particular social groups which the pension system is related to, as well as pension funds and the state. The goal is to present comprehensive overview on the pension system issues and also show possible solutions.
246

Estrutura populacional e história demográfica da tartaruga-verde (Chelonia mydas) no Atlântico Oeste / Population structure and demographic history of green turtle (Chelonia mydas) in the West Atlantic

Jordão, Juliana Costa 03 October 2013 (has links)
As tartarugas marinhas são répteis de vida longa que realizam extensas migrações entre áreas de alimentação e desova, resultando em estágios sucessivos de mistura e isolamento de estoques genéticos, espacial e temporalmente. A tartaruga-verde (Chelonia mydas) está ameaçada de extinção, e é fundamental entender sua dinâmica populacional e distribuição para o manejo e conservação da espécie. O objetivo deste estudo foi analisar a diversidade genética, estrutura populacional, origens dos indivíduos e história demográfica de C. mydas em três locais do Oceano Atlântico (estado do Rio de Janeiro, Brasil - área de alimentação; Guadalupe e Guiana Francesa - áreas de desova), com base em sequências da região controle do DNA mitocondrial (mtDNA) e 10 loci de microssatélites. As análises de mtDNA demonstraram que a área amostrada no Brasil tem perfil genético semelhante às outras áreas de alimentação da costa brasileira. De maneira semelhante, o perfil genético das duas áreas de desova é bastante similar ao de outros sítios reprodutivos na região do Caribe. As análises de estoque misto revelaram que os indivíduos juvenis no Brasil são provenientes principalmente da Ilha Ascensão, Guiana Francesa e Guiné Bissau. Os microssatélites detectaram estrutura genética entre as três populações, apesar de haver um fluxo de migrantes entre elas, especialmente de indivíduos da Guiana Francesa em direção ao Brasil e Guadalupe. Guiana Francesa, Guadalupe e Brasil apresentaram declínio populacional severo, detectado pelos microssatélites. Apesar da distribuição global, as populações de tartarugas-verdes estão sujeitas a diferentes pressões nos habitats que ocupam, e é importante entender quais populações estão ameaçadas. Este estudo enfatiza a importância da conectividade entre áreas de alimentação e desova que podem estar amplamente distribuídas de acordo com oportunidades ou restrições ecológicas, adicionando informações a respeito da dispersão e a dinâmica de tartarugas-verdes que frequentam o Oceano Atlântico / Sea turtles are reptiles with a long lifespan that undertake wide-ranging migrations through feeding and nesting sites, resulting in successive stages of mixing and isolating genetic stocks, both spatially and temporally. The green sea turtle (Chelonia mydas) is threatened with extinction, and it is essential to understand its population dynamics and distribution in order to manage and preserve the species. The aim of this study was to analyze the genetic diversity, population structure, natal origins and demographic history of C. mydas in three sites in the Atlantic Ocean (Rio de Janeiro state, Brazil - feeding ground; Guadeloupe and French Guiana - nesting sites), based on sequences of the mitochondrial DNA (mtDNA) control region and 10 microsatellites loci. The mtDNA analyses demonstrated that Brazilian samples have the same genetic profile of others collected in feeding grounds in the Brazilian coast. Similarly, the genetic profile of the nesting sites has resemblances to others in the Caribbean region. The mixed stock analyses revealed that most of the juveniles in Rio de Janeiro state come from Ascension Island, French Guiana and Guinea Bissau. Microsatellites detected genetic structure among the three populations, even with migration flows, especially in individuals from French Guiana to Brazil and Guadeloupe. French Guiana, Guadeloupe and Brazil presented a severe population decline, detected by the microsatellites analyses. Despite the worldwide distribution, green sea turtle populations undergo different pressures at the habitats they occupy, and it is important to understand which populations are threatened. This study emphasizes the importance of connecting nesting and feeding areas that can be widely distributed according to ecological opportunities or constraints, adding information on dispersion and population dynamics of green sea turtles on Atlantic Ocean
247

Impact of Distance, Diagnosis, and Demographics on Attendance for Rural Outpatient Treatment

Jensen, Trey Howard 01 January 2016 (has links)
Missed psychotherapy appointments inhibit mental health treatment, limit the availability of treatment to those waiting for care, and reduce clinician revenue. Previous research has revealed that the factors that predict missed appointments vary depending on the geographic location in which that research is conducted. There is not a complete understanding of the characteristics of people who miss appointments in a rural context. This study used information from 281 client records to examine the predictive relationships among missed appointments and the distance traveled to the clinic, mental health diagnosis, age, and gender at a rural outpatient mental health clinic. The purpose of this research was to identify the factors that significantly predicted if clients missed 30% or more scheduled psychotherapy appointments. The health belief model was used as the framework. Logistic regression analysis revealed that clients with a diagnosis of depression, bipolar disorder, or anxiety were more likely to miss 30% or more appointments. The distance traveled to the clinic did not predict missed appointments. This finding deviates from results in previous literature which found that long travel distances increase the likelihood of missed appointments. This could be due to the geographic region or how the client records were selected in this study. This study can have a positive impact by informing rural mental health clinics of factors that may predict the likelihood of missed appointments. Clinics could then use the information to develop empirically-supported retention interventions. Retention interventions could promote social change by increasing appointment attendance, which could improve overall patient care and reduce health care waste accrued by missed appointments.
248

Interactionality of trait-state music preference, individual variability, and music characteristics as a multi-axis paradigm for context-specific pain perception and management

Tan, Xueli 01 August 2015 (has links)
The purposes of this 3-phase study were 1) to identify salient individual variabilities and music characteristics associated with music therapy interventions for pain management, 2) to explore current pain management practices of music therapists, 3) to delineate any differences in general musical taste (trait) and context-specific music preference (state), as well as preferred music characteristics in healthy adults and cancer patients, 4) to investigate the contributions of individual variabilities, personality, behavioral coping styles, and pain levels in predicting changes from trait to state preferences and preferred music characteristics under various pain conditions, and 5) to investigate any differences in music preference patterns between healthy adults and cancer patients. In Phase I, 97 music therapists completed an online questionnaire to provide quantitative and qualitative data regarding the saliency of individual variabilities and music characteristics in determining the choice of music for pain management interventions, as well as their current practices with adult populations in clinical settings. In Phase II, 50 healthy adults (33 females, 17 males) ranging in age from 40 to 70 years (M = 57.04 ± 7.99) completed a battery of tests and questionnaires, including a Participant Intake Form (demographic information, music background, listening habits), an adapted Short Test of Music Preference – Revised (STOMP-R-A), a Music Characteristics Test, the Miller Behavioral Style Scale – abbreviated (MBSS-abbreviated), and the NEO Five-Factor Inventory-3 (NEO-FFI-3). The STOMP-R-A measured the participants’ trait and state preferences for 23 music genres. The Music Characteristics Test involved a music listening portion for participants to rate their preferences for various music characteristics. The MBSS-abbreviated measured behavioral coping styles and the NEO-FFI-3 measured the five dimensions of personality. In Phase III, 35 cancer patients (24 females, 11 males) ranging in age from 42 to 70 years (M = 57.71 ± 7.07) completed the same measurement tools as the ones used in Phase II, as well as the Short-Form McGill Pain Questionnaire–2 (SF-MPQ-2), which measured ratings for chronic, acute, and neuropathic pain. A one-way analysis of variance was used to test for response bias amongst the music therapists in Phase I. No response bias was found. Responses were reported as sums and converted to percentages of respondents for each selected response. Qualitative responses were analyzed using open coding and thematic development techniques. An intercoder was recruited to authenticate reliability for the qualitative findings. Music therapists identified age, ethnicity, culture, and religious preferences as important individual variabilities, and tempo, rhythmic complexity, and dynamics as salient music characteristics in their ratings. The results from Phase I informed the methodology for the next two phases of this study. Participants in Phases II and III were tested individually. The paired t-test was used to determine differences between trait and state music preferences across all 23 genres. The results indicated significant decreases from trait to state music preferences across music genres in both healthy adult and cancer patient groups. Calculations of the chi-square statistic and the McNemar’s test were used to detect differences between trait music preference and state music preference specific to each of the 23 genres. Multiple logistic regression analysis was used to examine the contributions of demographic factors, personality, behavioral coping style, and pain to changes from trait to state preferences and preferred music characteristics under four pain conditions. In Phase II, age, gender, and neuroticism predicted changes in trait-state preference for music genres; and gender and behavioral coping styles predicted changes in preferences for music characteristics under low-acute, high-acute, low-chronic, and high-chronic pain conditions. In Phase III, neuroticism predicted changes in trait-state preference for music genres; and age predicted changes in preferences for music characteristics under the four pain conditions. The independent t-test was used to determine differences between healthy adults’ and cancer patients’ ratings of the importance of music, music background, and music listening habits. No significant differences were found between the two groups. Healthy adults and cancer patients were most familiar with country music and rated oldies and rock as their most preferred music genres. Healthy adults reported familiarity with and preferences for greater number of genres compared to cancer patients. In general, both groups indicated decreased preferences for music under pain conditions. The findings from this study emphasized the importance of considerations for the interactions of trait-state music preferences, individual variabilities, and music characteristics as a paradigm for context-specific pain management in adult clinical settings.
249

Socio-Demographic and Economic Factors Affecting Fertility in Rural and Urban Thailand

Pitaktepsombati, Pichit 01 May 1981 (has links)
The major purpose of this study is to measure the relationship between socio-demographic and economic factors and fertility of rural and urban women in Thailand, utilizing national level survey data collected in 1972 and 1973. Specifically, a regression model of fertility and socio-demographic and economic variable s will be developed and analyzed. Also, a general comparison will be made between the results of the present study, based on the 1972 and 1973 surveys, with those from an earlier round of surveys conducted in 1969 and 1970.
250

Food Environments: What is the Role of Demographics in Figians' Decision Making Related to Food Choice and Overall Nutrition Behavior

Bradshaw, Sandra 01 May 2013 (has links)
Due to the recent increased quantity of nutrition-related diseases worldwide, current research recommends exploring environmental factors that influence this trend. The Islands of Fiji are of particular concern because of the growing number of non- communicable diseases. On the same small island, nutrition problems vary according to demographic. Thus, the different environments of each demographic constitute diverse food environments, which are manifested in varied nutrition concerns. This study explored environmental motivators of food choice for the Fijian population. Gathering the perspectives of Fijian Islanders using a narrative inquiry research format proved to be insightful in measuring the environmental influences of decisions pertaining to food.

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