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Nagarajan N. Renuga Teixeira Aurora A. C. Silva Sandra T. 《Population research and policy review》2021,40(2):187-210
Population Research and Policy Review - The issue of population ageing is no longer exclusively centred on developed countries. Empirical studies have proven that the rise in the proportion of the... 相似文献
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Landscape urbanization threatens plant phylogenetic diversity in the Brazilian Atlantic Forest 总被引:1,自引:0,他引:1
Valdecir Silva-Junior Danielle G. Souza Rubens T. Queiroz Luiz G. R. Souza Elâine M. S. Ribeiro Bráulio A. Santos 《Urban Ecosystems》2018,21(4):625-634
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation. 相似文献
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Maria Vaz-Patto Belén Bueno Óscar Ribeiro Laetitia Teixeira Rosa Marina Afonso 《European review of aging and physical activity》2017,14(1):9
Background
Centenarians are a growing population in Europe and present significant variability in motor and cognitive functions. The aim of our study was to characterize health status, as well as cognitive and motor functions in a group of Portuguese centenarians. In addition, our study also aimed at analyzing the relationship between cognitive functions and the burden of diseases affecting the elderly.Methods
Fifty-two centenarians were evaluated using the Mini-Mental State Examination, short version. Walking-related parameters (velocity and time spent in the 3 m walk test), grip strength and number of age-related illnesses were also measured. The relationship between cognitive scores and time spent in the three metre walk test, velocity, grip strength and number of diseases was analysed.Results
Cognitive scores showed a positive correlation with both handgrip strength and time spent in the three metre walk. In contrast, no association was found between cognitive scores and the presence/absence of disease, walking velocity or number of diseases present.Conclusions
These results suggest that in centenarians, cognitive functions may be related with motor functions.5.
André G. F. C. Costa Aline B. M. Vaz José Luiz P. Silva Leila D. Amorim 《Journal of applied statistics》2017,44(10):1827-1838
Clustered binary responses are often found in ecological studies. Data analysis may include modeling the marginal probability response. However, when the association is the main scientific focus, modeling the correlation structure between pairs of responses is the key part of the analysis. Second-order generalized estimating equations (GEE) are established in the literature. Some of them are more efficient in computational terms, especially facing large clusters. Alternating logistic regression (ALR) and orthogonalized residual (ORTH) GEE methods are presented and compared in this paper. Simulation results show a slightly superiority of ALR over ORTH. Marginal probabilities and odds ratios are also estimated and compared in a real ecological study involving a three-level hierarchical clustering. ALR and ORTH models are useful for modeling complex association structure with large cluster sizes. 相似文献
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In this work, we derive the copulas related to vectors obtained from the so-called chaotic stochastic processes. These are defined by the iteration of certain piecewise monotone functions of the interval [0, 1] to some initial random variable. We study some of its properties and present some examples. Since often these types of copulas do not have closed formulas, we provide a general approximation method which converges uniformly to the true copula. Our results cover a wide class of processes, including the so-called Manneville–Pomeau processes. The general theory is applied to the parametric estimation in certain chaotic processes. A Monte Carlo simulation study is also presented. 相似文献
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In this paper, we propose a new bivariate distribution, namely bivariate alpha-skew-normal distribution. The proposed distribution is very flexible and capable of generalizing the univariate alpha-skew-normal distribution as its marginal component distributions; it features a probability density function with up to two modes and has the bivariate normal distribution as a special case. The joint moment generating function as well as the main moments are provided. Inference is based on a usual maximum-likelihood estimation approach. The asymptotic properties of the maximum-likelihood estimates are verified in light of a simulation study. The usefulness of the new model is illustrated in a real benchmark data. 相似文献
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Luiz Claudio Marques Campos Patricia Maria Mendon?a Mario Aquino Alves 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2012,23(1):236-256
This article reflects on the importance of the relations between state and society in policy-making in the area of public
health. Several studies in various sectors such as health, education, and social services have made similar observations on
organizational dynamics and the institutionalization of different models of partnerships or contracts, often based on the
analytical model of three sectors. Individuals and their networks of relationships, however, remain an almost unexplored dimension
in these types of research. Against this backdrop, this study seeks to analyze the movement of HIV/AIDS activists to governmental
organizations working in this same field. The analysis raises questions concerning the forms of individual and institutional
learning that help to maintain the distinct character of innovation of the Brazilian policy. Professionals who cross the borders
hold a different profile once they have accumulated experience working with grassroots and local NGOs, and have also had the
chance to be trained and enhance their technical and managerial capacities, since the government has supported NGOs for a
long period. When combined, these experiences allow them to maintain relationships with social movements and give them the
ability to navigate through the government bureaucracy and handle technical information about fighting AIDS epidemics, making
it possible for them to negotiate strategic collaborations reflecting the interests of different groups. Hence, they constantly
reflect on the differences between government and social spaces, and keep questioning and modifying their roles in the light
of potential and existing complementarities. 相似文献
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de Almeida RA Veiga MM de Castro Moura Duarte FJ Meirelles LA Veiga LB 《Work (Reading, Mass.)》2012,41(Z1):4979-4982
Personal Protective Equipment (PPE) is considered the last preferred solution to an Occupational Safety Health (OSH) system. Brazilian OSH legislation assumes and requires PPE usage to neutralize the possibility of pesticide contamination. This study examines the inadequacy of the PPE used in a tomato crop, particularly from the standpoint of thermal comfort. This study made observations regarding heart rate and body temperature in a controlled environment using a treadmill (with and without PPE) of 12 volunteers; and during the process of rural labor (at rest and in normal work routine) of 2 actual rural workers. Comparing the results of the treadmill test (with and without PPE) which tried to reproduce the same level of effort and environmental conditions of the actual rural work, this study demonstrated that PPE makes thermoregulation harder and tympanic temperature reaches higher values with the same level of effort. Moreover, body temperature increases quickly: with PPE it took 15 minutes to raise 1°C in body temperature, compared to 40 minutes without PPE. The results of this study indicated that the use inadequate PPE might pose thermoregulation risk to rural workers. 相似文献
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da Silva LB da Costa Eulálio EJ Coutinho AS Soares EV de Lourdes Silva dos Santos R 《Work (Reading, Mass.)》2012,41(Z1):5540-5542
The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of two public Middle School students from Paraíba (Brazil). The target population included 8th grade groups involving 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck and about 90% of the students presented postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints. 相似文献