150 resultados para San (African people)


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Abstract : Understanding how biodiversity is distributed is central to any conservation effort and has traditionally been based on niche modeling and the causal relationship between spatial distribution of organisms and their environment. More recently, the study of species' evolutionary history and relatedness has permeated the fields of ecology and conservation and, coupled with spatial predictions, provides useful insights to the origin of current biodiversity patterns, community structuring and potential vulnerability to extinction. This thesis explores several key ecological questions by combining the fields of niche modeling and phylogenetics and using important components of southern African biodiversity. The aims of this thesis are to provide comparisons of biodiversity measures, to assess how climate change will affect evolutionary history loss, to ask whether there is a clear link between evolutionary history and morphology and to investigate the potential role of relatedness in macro-climatic niche structuring. The first part of my thesis provides a fine scale comparison and spatial overlap quantification of species richness and phylogenetic diversity predictions for one of the most diverse plant families in the Cape Floristic Region (CFR), the Proteaceae. In several of the measures used, patterns do not match sufficiently to argue that species relatedness information is implicit in species richness patterns. The second part of my thesis predicts how climate change may affect threat and potential extinction of southern African animal and plant taxa. I compare present and future niche models to assess whether predicted species extinction will result in higher or lower V phylogenetic diversity survival than what would be experienced under random extinction processes. l find that predicted extinction will result in lower phylogenetic diversity survival but that this non-random pattern will be detected only after a substantial proportion of the taxa in each group has been lost. The third part of my thesis explores the relationship between phylogenetic and morphological distance in southern African bats to assess whether long evolutionary histories correspond to equally high levels of morphological variation, as predicted by a neutral model of character evolution. I find no such evidence; on the contrary weak negative trends are detected for this group, as well as in simulations of both neutral and convergent character evolution. Finally, I ask whether spatial and climatic niche occupancy in southern African bats is influenced by evolutionary history or not. I relate divergence time between species pairs to climatic niche and range overlap and find no evidence for clear phylogenetic structuring. I argue that this may be due to particularly high levels of micro-niche partitioning. Résumé : Comprendre la distribution de la biodiversité représente un enjeu majeur pour la conservation de la nature. Les analyses se basent le plus souvent sur la modélisation de la niche écologique à travers l'étude des relations causales entre la distribution spatiale des organismes et leur environnement. Depuis peu, l'étude de l'histoire évolutive des organismes est également utilisée dans les domaines de l'écologie et de la conservation. En combinaison avec la modélisation de la distribution spatiale des organismes, cette nouvelle approche fournit des informations pertinentes pour mieux comprendre l'origine des patterns de biodiversité actuels, de la structuration des communautés et des risques potentiels d'extinction. Cette thèse explore plusieurs grandes questions écologiques, en combinant les domaines de la modélisation de la niche et de la phylogénétique. Elle s'applique aux composants importants de la biodiversité de l'Afrique australe. Les objectifs de cette thèse ont été l) de comparer différentes mesures de la biodiversité, 2) d'évaluer l'impact des changements climatiques à venir sur la perte de diversité phylogénétique, 3) d'analyser le lien potentiel entre diversité phylogénétique et diversité morphologique et 4) d'étudier le rôle potentiel de la phylogénie sur la structuration des niches macro-climatiques des espèces. La première partie de cette thèse fournit une comparaison spatiale, et une quantification du chevauchement, entre des prévisions de richesse spécifique et des prédictions de la diversité phylogénétique pour l'une des familles de plantes les plus riches en espèces de la région floristique du Cap (CFR), les Proteaceae. Il résulte des analyses que plusieurs mesures de diversité phylogénétique montraient des distributions spatiales différentes de la richesse spécifique, habituellement utilisée pour édicter des mesures de conservation. La deuxième partie évalue les effets potentiels des changements climatiques attendus sur les taux d'extinction d'animaux et de plantes de l'Afrique australe. Pour cela, des modèles de distribution d'espèces actuels et futurs ont permis de déterminer si l'extinction des espèces se traduira par une plus grande ou une plus petite perte de diversité phylogénétique en comparaison à un processus d'extinction aléatoire. Les résultats ont effectivement montré que l'extinction des espèces liées aux changements climatiques pourrait entraîner une perte plus grande de diversité phylogénétique. Cependant, cette perte ne serait plus grande que celle liée à un processus d'extinction aléatoire qu'à partir d'une forte perte de taxons dans chaque groupe. La troisième partie de cette thèse explore la relation entre distances phylogénétiques et morphologiques d'espèces de chauves-souris de l'Afrique australe. ll s'agit plus précisément de déterminer si une longue histoire évolutive correspond également à des variations morphologiques plus grandes dans ce groupe. Cette relation est en fait prédite par un modèle neutre d'évolution de caractères. Aucune évidence de cette relation n'a émergé des analyses. Au contraire, des tendances négatives ont été détectées, ce qui représenterait la conséquence d'une évolution convergente entre clades et des niveaux élevés de cloisonnement pour chaque clade. Enfin, la dernière partie présente une étude sur la répartition de la niche climatique des chauves-souris de l'Afrique australe. Dans cette étude je rapporte temps de divergence évolutive (ou deux espèces ont divergé depuis un ancêtre commun) au niveau de chevauchement de leurs niches climatiques. Les résultats n'ont pas pu mettre en évidence de lien entre ces deux paramètres. Les résultats soutiennent plutôt l'idée que cela pourrait être I dû à des niveaux particulièrement élevés de répartition de la niche à échelle fine.

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AIMS: To estimate physical activity trajectories for people who quit smoking, and compare them to what would have been expected had smoking continued. DESIGN, SETTING AND PARTICIPANTS: A total of 5115 participants in the Coronary Artery Risk Development in Young Adults Study (CARDIA) study, a population-based study of African American and European American people recruited at age 18-30 years in 1985/6 and followed over 25 years. MEASUREMENTS: Physical activity was self-reported during clinical examinations at baseline (1985/6) and at years 2, 5, 7, 10, 15, 20 and 25 (2010/11); smoking status was reported each year (at examinations or by telephone, and imputed where missing). We used mixed linear models to estimate trajectories of physical activity under varying smoking conditions, with adjustment for participant characteristics and secular trends. FINDINGS: We found significant interactions by race/sex (P = 0.02 for the interaction with cumulative years of smoking), hence we investigated the subgroups separately. Increasing years of smoking were associated with a decline in physical activity in black and white women and black men [e.g. coefficient for 10 years of smoking: -0.14; 95% confidence interval (CI) = -0.20 to -0.07, P < 0.001 for white women]. An increase in physical activity was associated with years since smoking cessation in white men (coefficient 0.06; 95% CI = 0 to 0.13, P = 0.05). The physical activity trajectory for people who quit diverged progressively towards higher physical activity from the expected trajectory had smoking continued. For example, physical activity was 34% higher (95% CI = 18 to 52%; P < 0.001) for white women 10 years after stopping compared with continuing smoking for those 10 years (P = 0.21 for race/sex differences). CONCLUSIONS: Smokers who quit have progressively higher levels of physical activity in the years after quitting compared with continuing smokers.

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It is commonly found that young people tend to adopt the political party choice of their parents. However, far less is known about the applicability of this theory when investigating radical right support. Using the Swiss Household panel data (1999e2007), this study empirically identifies the relationship between parents' preference for the Swiss radical right party SVP and their attitudes toward immigrants and the EU, and their offspring's preference for the SVP. Disaggregating fathers' and mothers' influence reveals that in particular, mothers' SVP support plays a role in SVP support among young people, even after controlling for educational similarities. We also demonstrate that girls are more likely to be influenced by their mothers than are boys. Furthermore, parents' negative attitudes toward the EU exert a positive influence on their children's radical right voting, independent of their voting pattern.

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Objective: We assessed the awareness, treatment and control of hypertension in the Seychelles between 1989 and 2013. In the Seychelles, heath care is free to all inhabitants within a national health system, inclusive all hypertension medications. Design and method: Four surveys were conducted in 1989, 1994, 2004 and 2013 (Seychelles Heart Studies I, II, III and IV) in random samples of the population aged 25-64 (N >1000 and participation rate >75% in each sur acceptance of the program, though no objective index could be calculated. In total, 15% of device measurements were above high normal values and would correspond to either newly diagnosed HNT (second measurement required) or to poorly controlled known HTN. It should be stressed that 53 women without HTN who completed the questionnaire had abnormal BP values, including the 29 women who also contacted the research team. It could be speculated that approximately 2% of women would be first diagnosed with HTN following the completion of the initial phase of the screening program. Conclusions: Hypertension screening in the hair salon setting was proved to be conveniently applicable and well accepted both by owners and by customers and could lead to the new diagnosis of hypertension for 2% of the female clients. Further research is warranted to assess the effectiveness of the program.

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Guided by a modified information-motivation-behavioral skills model, this study identified predictors of condom use among heterosexual people living with HIV with their steady partners. Consecutive patients at 14 European HIV outpatient clinics received an anonymous, standardized, self-administered questionnaire between March and December 2007. Data were analyzed using descriptive statistics and two-step backward elimination regression analyses stratified by gender. The survey included 651 participants (n = 364, 56% women; n = 287, 44%). Mean age was 39 years for women and 43 years for men. Most had acquired HIV sexually and more than half were in a serodiscordant relationship. Sixty-three percent (n = 229) of women and 59% of men (n = 169) reported at least one sexual encounter with a steady partner 6 months prior to the survey. Fifty-one percent (n = 116) of women and 59% of men (n = 99) used condoms consistently with that partner. In both genders, condom use was positively associated with subjective norm conducive to condom use, and self-efficacy to use condoms. Having a partner whose HIV status was positive or unknown reduced condom use. In men, higher education and knowledge about condom use additionally increased condom use, while the use of erectile-enhancing medication decreased it. For women, HIV disclosure to partners additionally reduced the likelihood of condom use. Positive attitudes to condom use and subjective norm increased self-efficacy in both genders, however, a number of gender-related differences appeared to influence self-efficacy. Service providers should pay attention to the identified predictors of condom use and adopt comprehensive and gender-related approaches for preventive interventions with people living with HIV.

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Afro-Palearctic migrant species are exposed to parasites at both breeding and over-wintering grounds. The house martin Delichon urbicum is one such migratory species facing high instances of blood parasite infection. In an attempt to determine whether breeding European house martins harbour similar blood parasite communities to populations breeding in North Africa, birds were sampled at their breeding grounds in Switzerland and Algeria. Moreover, haemosporidian prevalence and parasite communities were compared to published data sets on Spanish and Dutch breeding populations. This study furthermore wanted to establish whether co-infection with multiple genera or lineages of parasites had negative effects on host body condition. Breeding house martins caught in Algeria showed a higher prevalence of avian haemosporidian parasites than did European populations. Swiss house martins showed a prevalence comparable to that of Spanish and Dutch populations. There were slight differences in the haemosporidian community between European and North-African populations in terms of composition and abundance of each lineage. Similar to the Dutch house martins, but in contrast to the Spanish population, infection status and number of genera of parasites infecting single hosts did not inFLuence Swiss house martin body condition.

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Introduction: Few studies have reported the distribution of all hospital admissions at the entire country level in low and middle-income countries (LMICs). We examined this question in Seychelles, a rapidly developing small island state in the Africa region, in which access to health care is provided free of charge to all inhabitants through a national health system and all hospital admissions are routinely registered. Methods: Based on all admissions to all hospitals in Seychelles in 2005-2008, we calculated the distribution of hospital admissions, age at admission, length of stay and bed occupancy (i.e. cumulated number of patients * number of days spent in all hospitals) according to both hospital departments and broad causes of diseases (using codes of the ICD-10 classification of diseases). Results: Bed occupancy was largest in the surgical wards (36.7% of all days spent in all hospitals), followed by the medical wards (24.3%), gynecology/obstetrics wards (18.4%), pediatric wards (11.2%), and psychiatric wards (7.2%). According to broad causes of diseases/conditions, bed occupancy was highest for obstetrics/gynecology conditions (19.9% of all days spent at hospital), mental diseases (8.6%), cardiovascular diseases (8.1%), upper aerodigestive/pulmonary diseases (8%), infectious/parasitic diseases (8%), gastrointestinal diseases (7.2%), and urogenital diseases (6.7%). Adjusted to 100'000 population, 153 hospital beds are needed every day, including 31 for obstetrics/gynecologic conditions, 13 for mental diseases, 12 for cardiovascular diseases, 12 for upper aerodigestive diseases, 12 for infectious/parasitic diseases, and 11 for gastrointestinal diseases. Conclusion: Our findings give a good indication of the overall distribution of admissions according to both hospital departments and broad causes of diseases in a middle-income country. These findings provide important information for health care planning at the national level

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Résumé Alors que les pratiques religieuses régulières diminuent et que les groupes religieux majoritaires perdent des membres formellement enregistrés, une évènementisation de l'appartenance religieuse peut être observée depuis environ deux décennies. Dans un premier exemple, l'auteure montre que le réseau transnational de la confrérie soufie des Mourides resserre les liens entre adeptes dans un contexte migratoire qui tend à fragiliser les relations sociales. La confrérie y fait face à travers une spectacularisation de la pratique religieuse, occupant l'espace public à Harlem ou, dans une moindre mesure, à Paris. Le second exemple traite du pèlerinage aux Saintes et Saints d'Afrique dans la ville valaisanne de Saint Maurice. Ce dernier fut inventé par l'Église catholique suisse afin d'attirer des migrants africains, mais aussi afin de redynamiser une pratique religieuse ordinaire en perte de vitesse. L'évènement a lieu en même temps que le pèlerinage de Namugongo en Ouganda, réunissant plus d'un demi-million de personnes. Les communautés évènementielles ainsi créées sont-elles durables ou plutôt liquides ? Abstract While regular religious practice is decreasing and the major religious groups are losing formally registered members, a 'spectacularization' of religious belonging can be observed over the last two decades. The author presents two examples to support this argument. In the first, the transnational network of the Murids, a Sufi brotherhood, has tried to reinforce the relations between its members, which become fragile during migration. The brotherhood occupies a public space in Harlem, and, to a lesser extent, in Paris, in a spectacularization of religious belonging, in order to remain attractive to migrants. The second example deals with the pilgrimage dedicated to African Saints in the Swiss town of Saint Maurice. This event was invented by the missionary service of the Swiss Catholic Church in order to attract African migrants, but also in order to make ordinary religious practice more appealing. The event takes place at the same time as the Ugandan pilgrimage of Namugongo, which assembles more than half a million people. However, are these 'event communities' sustainable or ephemeral?

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BACKGROUND: To test the inflammatory origin of cardiovascular disease, as opposed to its origin in western lifestyle. Population-based assessment of the prevalences of cardiovascular risk factors and cardiovascular disease in an inflammation-prone African population, including electrocardiography and ankle-arm index measurement. Comparison with known prevalences in American and European societies. METHODOLOGY/PRINCIPAL FINDINGS: Traditional population in rural Ghana, characterised by adverse environmental conditions and a high infectious load. Population-based sample of 924 individuals aged 50 years and older. Median values for cardiovascular risk factors, including waist circumference, BMI, blood pressure, and markers of glucose and lipid metabolism and inflammation. Prevalence of myocardial infarction detected by electrocardiography and prevalence of peripheral arterial disease detected by ankle-arm index. When compared to western societies, we found the Ghanaians to have more proinflammatory profiles and less cardiovascular risk factors, including obesity, dysglycaemia, dyslipidaemia, and hypertension. Prevalences of cardiovascular disease were also lower. Definite myocardial infarction was present in 1.2% (95%CI: 0.6 to 2.4%). Peripheral arterial disease was present in 2.8% (95%CI: 1.9 to 4.1%). CONCLUSIONS/SIGNIFICANCE: Taken together, our data indicate that for the pathogenesis of cardiovascular disease inflammatory processes alone do not suffice and additional factors, probably lifestyle-related, are mandatory.

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BACKGROUND: Circulating 25-hydroxyvitamin D [25(OH)D] concentration is inversely associated with peripheral arterial disease and hypertension. Vascular remodeling may play a role in this association, however, data relating vitamin D level to specific remodeling biomarkers among ESRD patients is sparse. We tested whether 25(OH)D concentration is associated with markers of vascular remodeling and inflammation in African American ESRD patients.METHODS: We conducted a cross-sectional study among ESRD patients receiving maintenance hemodialysis within Emory University-affiliated outpatient hemodialysis units. Demographic, clinical and dialysis treatment data were collected via direct patient interview and review of patients records at the time of enrollment, and each patient gave blood samples. Associations between 25(OH)D and biomarker concentrations were estimated in univariate analyses using Pearson's correlation coefficients and in multivariate analyses using linear regression models. 25(OH) D concentration was entered in multivariate linear regression models as a continuous variable and binary variable (<15 ng/ml and =15 ng/ml). Adjusted estimate concentrations of biomarkers were compared between 25(OH) D groups using analysis of variance (ANOVA). Finally, results were stratified by vascular access type.RESULTS: Among 91 patients, mean (standard deviation) 25(OH)D concentration was 18.8 (9.6) ng/ml, and was low (<15 ng/ml) in 43% of patients. In univariate analyses, low 25(OH) D was associated with lower serum calcium, higher serum phosphorus, and higher LDL concentrations. 25(OH) D concentration was inversely correlated with MMP-9 concentration (r = -0.29, p = 0.004). In multivariate analyses, MMP-9 concentration remained negatively associated with 25(OH) D concentration (P = 0.03) and anti-inflammatory IL-10 concentration positively correlated with 25(OH) D concentration (P = 0.04).CONCLUSIONS: Plasma MMP-9 and circulating 25(OH) D concentrations are significantly and inversely associated among ESRD patients. This finding may suggest a potential mechanism by which low circulating 25(OH) D functions as a cardiovascular risk factor.

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Around 11.5 * 106 m3 of rock detached from the eastern slope of the Santa Cruz valley (San Juan province, Argentina) in the first fortnight of January 2005. The rockslide?debris avalanche blocked the course, resulting in the development of a lake with maximum length of around 3.5 km. The increase in the inflow rate from 47,000?74,000 m3/d between April and October to 304,000 m3/d between late October and the first fortnight of November, accelerated the growing rate of the lake. On 12 November 2005 the dam failed, releasing 24.6 * 106 m3 of water. The resulting outburst flood caused damages mainly on infrastructure, and affected the facilities of a hydropower dam which was under construction 250 km downstream from the source area. In this work we describe causes and consequences of the natural dam formation and failure, and we dynamically model the 2005 rockslide?debris avalanche with DAN3D. Additionally, as a volume ~ 24 * 106 m3of rocks still remain unstable in the slope, we use the results of the back analysis to forecast the formation of a future natural dam. We analyzed two potential scenarios: a partial slope failure of 6.5 * 106 m3 and a worst case where all the unstable volume remaining in the slope fails. The spreading of those potential events shows that a new blockage of the Santa Cruz River is likely to occur. According to their modeled morphometry and the contributing watershed upstream the blockage area, as the one of 2005, the dams would also be unstable. This study shows the importance of back and forward analysis that can be carried out to obtain critical information for land use planning, hazards mitigation, and emergency management.