708 resultados para Demography.


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The 5` cis-regulatory region of the CCR5 gene exhibits a strong signature of balancing selection in several human populations. Here we analyze the polymorphism of this region in Amerindians from Amazonia, who have a complex demographic history, including recent bottlenecks that are known to reduce genetic variability. Amerindians show high nucleotide diversity (pi = 0.27%) and significantly positive Tajima`s D, and carry haplotypes associated with weak and strong gene expression. To evaluate whether these signatures of balancing selection could be explained by demography, we perform neutrality tests based on empiric and simulated data. The observed Tajima`s D was higher than that of other world populations: higher than that found for 18 noncoding regions of South Amerindians, and higher than 99.6% of simulated genealogies, which assume nonequilibrium conditions. Moreover, comparing Amerindians and Asians, the Fst for CCR5 cis-regulatory region was unusually low, in relation to neutral markers. These findings indicate that, despite their complex demographic history, South Amerindians carry a detectable signature of selection on the CCR5 cis-regulatory region. (C) 2010 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

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The increase in biodiversity from high to low latitudes is a widely recognized biogeographical pattern. According to the latitudinal gradient hypothesis (LGH), this pattern was shaped by differential effects of Late Quaternary climatic changes across a latitudinal gradient. Here, we evaluate the effects of climatic changes across a tropical latitudinal gradient and its implications to diversification of an Atlantic Forest (AF) endemic passerine. We studied the intraspecific diversification and historical demography of Sclerurus scansor, based on mitochondrial (ND2, ND3 and cytb) and nuclear (FIB7) gene sequences. Phylogenetic analyses recovered three well-supported clades associated with distinct latitudinal zones. Coalescent-based methods were applied to estimate divergence times and changes in effective population sizes. Estimates of divergence times indicate that intraspecific diversification took place during Middle-Late Pleistocene. Distinct demographic scenarios were identified, with the southern lineage exhibiting a clear signature of demographic expansion, while the central one remained more stable. The northern lineage, contrasting with LGH predictions, exhibited a clear sign of a recent bottleneck. Our results suggest that different AF regions reacted distinctly, even in opposite ways, under the same climatic period, producing simultaneously favourable scenarios for isolation and contact among populations.

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Fire is an important factor in several ecosystems, affecting plant population biology. Campos grasslands are under constant influence of disturbance, mostly grazing and fire. However, few studies evaluated the effect of fire on plant population biology of grassland species. Therefore, we aim to analyze the effect of fire on the population biology of four species, from different functional groups and regeneration strategies: Chaptalia runcinata (forb, resprouter, absence of belowground organ), Vernonia flexuosa (forb, resprouter, presence of rhizophore), Eupatorium ligulaefolium (shrub, resprouter, presence of xylopodium) and Heterothalamus psiadioides (shrub, obligate seeder). Seven plots were established in different sites in southern Brazil: frequently burned (FB) and excluded from fire since 6 years (E). All plots were subjected to controlled burns during summer. Before experiments, populations were sampled. Further observations were carried out after 90 and after 360 days of fire experiments. In addition, we counted the number of seedlings and resprouters recruited after fire. Heat shock experiments were conducted with two species (H. psiadioides and V. flexuosa), as well as the study of the bud bank of the following species: E. ligulaefolium and V. flexuosa. The obligate seeder species had all individuals killed by fire and established only after 1 year. Resprouters, however, showed new stems immediately after fire. E. ligulaefolium and V. flexuosa showed only vegetative regeneration from belowground organs and more individuals in excluded sites 1 year after the fire. The bud bank of E. ligulaefolium tended to be larger in excluded sites, whilst V. flexuosa showed an opposite result. High temperatures did not enhance nor kill seeds from both studied species. Vegetative regeneration was the most important strategy for all studied species, except for H. psiadioides, the obligate seeder species. Fire thus, plays an important role on population structure and demography, being also important for plant recruitment.

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The narrative of the United States is of a "nation of immigrants" in which the language shift patterns of earlier ethnolinguistic groups have tended towards linguistic assimilation through English. In recent years, however, changes in the demographic landscape and language maintenance by non-English speaking immigrants, particularly Hispanics, have been perceived as threats and have led to calls for an official English language policy.This thesis aims to contribute to the study of language policy making from a societal security perspective as expressed in attitudes regarding language and identity originating in the daily interaction between language groups. The focus is on the role of language and American identity in relation to immigration. The study takes an interdisciplinary approach combining language policy studies, security theory, and critical discourse analysis. The material consists of articles collected from four newspapers, namely USA Today, The New York Times, Los Angeles Times, and San Francisco Chronicle between April 2006 and December 2007.Two discourse types are evident from the analysis namely Loyalty and Efficiency. The former is mainly marked by concerns of national identity and contains speech acts of security related to language shift, choice and English for unity. Immigrants are represented as dehumanised, and harmful. Immigration is given as sovereignty-related, racial, and as war. The discourse type of Efficiency is mainly instrumental and contains speech acts of security related to cost, provision of services, health and safety, and social mobility. Immigrants are further represented as a labour resource. These discourse types reflect how the construction of the linguistic 'we' is expected to be maintained. Loyalty is triggered by arguments that the collective identity is threatened and is itself used in reproducing the collective 'we' through hegemonic expressions of monolingualism in the public space and semi-public space. The denigration of immigrants is used as a tool for enhancing societal security through solidarity and as a possible justification for the denial of minority rights. Also, although language acquisition patterns still follow the historical trend of language shift, factors indicating cultural separateness such as the appearance of speech communities or the use of minority languages in the public space and semi-public space have led to manifestations of intolerance. Examples of discrimination and prejudice towards minority groups indicate that the perception of worth of a shared language differs from the actual worth of dominant language acquisition for integration purposes. The study further indicates that the efficient working of the free market by using minority languages to sell services or buy labour is perceived as conflicting with nation-building notions since it may create separately functioning sub-communities with a new cultural capital recognised as legitimate competence. The discourse types mainly represent securitising moves constructing existential threats. The perception of threat and ideas of national belonging are primarily based on a zero-sum notion favouring monolingualism. Further, the identity of the immigrant individual is seen as dynamic and adaptable to assimilationist measures whereas the identity of the state and its members are perceived as static. Also, the study shows that debates concerning language status are linked to extra-linguistic matters. To conclude, policy makers in the US need to consider the relationship between four factors, namely societal security based on collective identity, individual/human security, human rights, and a changing linguistic demography, for proposed language intervention measures to be successful.

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Baby boomers and elderly care: expectations in print media about a new kind of care users The Swedish baby boomer generation – known as the forties generation – has been characterized as youthful and powerful. At present, members of this generation are entering the category of old age and in about ten years they will start reaching ages where the likelihood of encountering elderly care increases significantly. The present study reports on how this expected meeting has been discussed in Swedish newspapers. Data consisted of 481 articles during the period 1995–2012 and was analyzed through qualitative content analysis. Results show that the generation was predicted to become a new type of demanding and self-conscious care users. Claims were backed by descriptions of formative events and typical characteristics that were projected onto a future as care user. Such projections tended to portray care users of present time as passive and submissive, and partly responsible for problems associated with elderly care 

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Applying microeconomic theory, we develop a forecasting model for firm entry into local markets and test this model using data from the Swedish wholesale industry. The empirical analysis is based on directly estimating the profit function of wholesale firms. As in previous entry studies, profits are assumed to depend on firm- and location-specific factors,and the profit equation is estimated using panel data econometric techniques. Using the residuals from the profit equation estimations, we identify local markets in Sweden where firm profits are abnormally high given the level of all independent variables included in the profit function. From microeconomic theory, we then know that these local markets should have higher net entry than other markets, all else being equal, and we investigate this in a second step,also using a panel data econometric model. The results of estimating the net-entry equation indicate that four of five estimated models have more net entry in high-return municipalities, but the estimated parameter is only statistically significant at conventional levels in one of our estimated models.

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There was a significant decline in hospitalizations for acute diarrhea in children younger than 1 year of age in Brazil between 1992 to 2001. The less economically developed state of Rio Grande do Norte is a case example of the national trend. In this work, we show a significant association between improvements in socioeconomic variables as well as increased access to sanitation and the decreased rate of hospitalization. Additionally, we observed a positive, seasonal correlation between rainfall and hospitalizations. Most notably, however, we show that improvements in income and inflation were positively correlated with a decline in hospitalizations. Improvements in public health infrastructure, socioeconomic variables like education and literacy, and increased investment in health services were important in reducing severe early childhood diarrheas. However, the data suggests that increased buying power and reductions in poverty played an equally crucial role in reducing hospitalizations for acute diarrhea in infants in Brazil. The work includes elements of the demography of the period for the age groups involved, children under one year, women in fertile age and fertility rate

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One of the greatest challenges of demography, nowadays, is to obtain estimates of mortality, in a consistent manner, mainly in small areas. The lack of this information, hinders public health actions and leads to impairment of quality of classification of deaths, generating concern on the part of demographers and epidemiologists in obtaining reliable statistics of mortality in the country. In this context, the objective of this work is to obtain estimates of deaths adjustment factors for correction of adult mortality, by States, meso-regions and age groups in the northeastern region, in 2010. The proposal is based on two lines of observation: a demographic one and a statistical one, considering also two areas of coverage in the States of the Northeast region, the meso-regions, as larger areas and counties, as small areas. The methodological principle is to use the General Equation and Balancing demographic method or General Growth Balance to correct the observed deaths, in larger areas (meso-regions) of the states, since they are less prone to breakage of methodological assumptions. In the sequence, it will be applied the statistical empirical Bayesian estimator method, considering as sum of deaths in the meso-regions, the death value corrected by the demographic method, and as reference of observation of smaller area, the observed deaths in small areas (counties). As results of this combination, a smoothing effect on the degree of coverage of deaths is obtained, due to the association with the empirical Bayesian Estimator, and the possibility of evaluating the degree of coverage of deaths by age groups at counties, meso-regions and states levels, with the advantage of estimete adjustment factors, according to the desired level of aggregation. The results grouped by State, point to a significant improvement of the degree of coverage of deaths, according to the combination of the methods with values above 80%. Alagoas (0.88), Bahia (0.90), Ceará (0.90), Maranhão (0.84), Paraíba (0.88), Pernambuco (0.93), Piauí (0.85), Rio Grande do Norte (0.89) and Sergipe (0.92). Advances in the control of the registry information in the health system, linked to improvements in socioeconomic conditions and urbanization of the counties, in the last decade, provided a better quality of information registry of deaths in small areas

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Os nascimentos ocorridos em uma população consistem em informação de grande valia para diversos estudos e planejamento de políticas públicas. O Sistema de informações sobre Nascidos Vivos (SINASC) representa uma promissora fonte de informação sobre o tema, uma vez que coleta continuamente e no âmbito municipal, dados sobre nascimentos. Tendo em vista a necessidade de avaliação contínua do SINASC e o panorama do declínio da fecundidade no Nordeste, objetivou-se avaliar a qualidade das informações provenientes do SINASC para o Nordeste, estados e microrregiões, nos anos 2000 e 2010, utilizando o Censo Demográfico como informação de referência, avaliando a cobertura do SINASC e identificando níveis e padrões de fecundidade. Pretendeu-se ainda verificar a relação entre os níveis de fecundidade, o grau de cobertura do SINASC e as condições socioeconômicas das microrregiões sintetizadas pelo Índice Social de Desenvolvimento Municipal (ISDM), utilizando-se a análise de cluster, associada à análise de variância (ANOVA) e o teste de Tukey. Por último, analisou-se a incompletude no preenchimento dos campos da Declaração de Nascido Vivo (DNV). De acordo com os resultados, observou-se que houve ampliação da qualidade das informações do SINASC no período estudado, resultando em uma maior aproximação das TFTs oriundas das duas fontes de dados consideradas no estudo. Maranhão e Paraíba foram os estados com maiores ganhos em cobertura das TFTs no período, e os estados do Rio Grande do Norte e Sergipe revelaram um grau de cobertura ligeiramente inferior em 2010 frente aos resultados de 2000, bem como ainda persistem várias microrregiões com TFTs oriundas do SINASC bem abaixo daquelas estimadas pelo Censo. Na verificação da associação entre o ISDM, TFTs e cobertura, a análise de cluster resultou em três agrupamentos, GrISDM A com melhores coberturas, ISDM e mais baixas TFT; GrISDM B , intermediário e GrISDM C com piores coberturas, ISDM e TFT mais altas. Notou-se a evolução das condições socioeconômicas no Nordeste, tendo o GrISDM A passado de 8% do total de microrregiões em 2000 para 37% em 2010. Reiterou-se ainda que quanto melhores as condições socioeconômicas de uma população, menores são as TFTs e melhores as coberturas do SINASC. A análise de variância apontou interações significativas entre o ano estudado versus ISDM (p-valor < 0,016) e o ano versus fonte de informação (p-valor < 0,020), e o teste Tukey apontou que não houve similaridade entre as médias das TFT das fontes Censo versus SINASC no período, fato que aponta para a captação ainda deficiente do SINASC nas microrregiões. O resultado da análise de variância da cobertura do SINASC em relação ao Censo apresentou uma interação significativa entre as variáveis UF versus Ano (p-valor < 0,0001), causada pelos estados que apresentaram queda de cobertura entre 2000 e 2010. Quanto à incompletude dos itens da DNV, evidenciou-se uma melhor coleta no período, embora alguns itens ainda careçam de atenção, como o apgar no 1º e 5º minuto e ocupação da mãe, sendo esta a que apresenta maiores percentuais de informações ignoradas. Destaca-se a possibilidade de preenchimento inconsistente nas variáveis referentes ao histórico de gestações anteriores, com o uso da informação zero inserida no lugar da informação ignorado . Concluiu-se que o SINASC é uma importante base de dados sobre nascimentos e que dispõe de dados confiáveis para o acompanhamento dos nascimentos e de seu panorama epidemiológico no Nordeste brasileiro, embora para alguns estados, assim como para algumas microrregiões, ainda faz-se necessária a ampliação da cobertura do Sistema. As informações constantes na DNV podem servir como embasamento para diversos estudos sobre as condições epidemiológicas dos nascituros e das suas mães, e dos indicadores baseados as informações dos nascimentos

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This work was developed in the research line: "The habitus of study: builder of a new reality in the basic education of metropolitan area Natal" which is being developed with the support of CAPES by the Centre for Education. Acts, especially the problem of academic performance of students in basic education of the public in the Metropolitan Region of Natal (RMN). Thus, the aim of this paper is to construct a typology of students in the 9th year of basic education, attending the public schools (state or municipal) of MRN, 2009, and assess, according to these profiles, what personal characteristics student and their families: economic, social and cultural capital as well as teaching practices create environments capable of favoring a good educational development as measured by the performance obtained in the assessments in mathematics and English language. The data used were provided through the microdata Brazil Exam 2009 held by INEP. We used the methods Grade of Membership (GoM) for construction of profiles relevance of students according to the characteristics already mentioned. With these profiles was verified, which were effectively generating good performance in school curriculum components evaluated. The findings indicate that students belonging to the profile considered good environment, able to achieve better school performance both in Portuguese as in Mathematics, compared to the extreme profiles and adverse deficit