849 resultados para Urban-rural Differences


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The performance of three urban land surface models, run in offline mode, with their default external parameters, is evaluated for two distinctly different sites in Helsinki: Torni and Kumpula. The former is a dense city centre site with 22% vegetation, while the latter is a suburban site with over 50% vegetation. At both locations the models are compared against sensible and latent heat fluxes measured using the eddy covariance technique, along with snow depth observations. The cold climate experienced by the city causes strong seasonal variations that include snow cover and stable atmospheric conditions. Most of the time the three models are able to account for the differences between the study areas as well as the seasonal and diurnal variability of the energy balance components. However, the performances are not systematic across the modelled components, season and surface type. The net all-wave radiation is well simulated, with the greatest uncertainties related to snowmelt timing, when the fraction of snow cover has a key role, particularly in determining the surface albedo. For the turbulent fluxes, more variation between the models is seen which can partly be explained by the different methods in their calculation and partly by surface parameter values. For the sensible heat flux, simulation of wintertime values was the main problem, which also leads to issues in predicting near-surface stabilities particularly at the dense city centre site. All models have the most difficulties in simulating latent heat flux. This study particularly emphasizes that improvements are needed in the parameterization of anthropogenic heat flux and thermal parameters in winter, snow cover in spring and evapotranspiration in order to improve the surface energy balance modelling in cold climate cities.

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Ambient concentrations of trace elements with 2 h time resolution were measured in PM10–2.5, PM2.5–1.0 and PM1.0–0.3 size ranges at kerbside, urban background and rural sites in London during winter 2012. Samples were collected using rotating drum impactors (RDIs) and subsequently analysed with synchrotron radiation-induced X-ray fluorescence spectrometry (SR-XRF). Quantification of kerb and urban increments (defined as kerb-to-urban and urban-to-rural concentration ratios, respectively), and assessment of diurnal and weekly variability provided insight into sources governing urban air quality and the effects of urban micro-environments on human exposure. Traffic-related elements yielded the highest kerb increments, with values in the range of 10.4 to 16.6 for SW winds (3.3–6.9 for NE) observed for elements influenced by brake wear (e.g. Cu, Sb, Ba) and 5.7 to 8.2 for SW (2.6–3.0 for NE) for other traffic-related processes (e.g. Cr, Fe, Zn). Kerb increments for these elements were highest in the PM10–2.5 mass fraction, roughly twice that of the PM1.0–0.3 fraction. These elements also showed the highest urban increments (~ 3.0), although no difference was observed between brake wear and other traffic-related elements. All elements influenced by traffic exhibited higher concentrations during morning and evening rush hours, and on weekdays compared to weekends, with the strongest trends observed at the kerbside site, and additionally enhanced by winds coming directly from the road, consistent with street canyon effects. Elements related to mineral dust (e.g. Al, Si, Ca, Sr) showed significant influences from traffic-induced resuspension, as evidenced by moderate kerb (3.4–5.4 for SW, 1.7–2.3 for NE) and urban (~ 2) increments and increased concentrations during peak traffic flow. Elements related to regional transport showed no significant enhancement at kerb or urban sites, with the exception of PM10–2.5 sea salt (factor of up to 2), which may be influenced by traffic-induced resuspension of sea and/or road salt. Heavy-duty vehicles appeared to have a larger effect than passenger vehicles on the concentrations of all elements influenced by resuspension (including sea salt) and wearing processes. Trace element concentrations in London were influenced by both local and regional sources, with coarse and intermediate fractions dominated by traffic-induced resuspension and wearing processes and fine particles influenced by regional transport.

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The Surface Urban Energy and Water Balance Scheme (SUEWS) is evaluated at two locations in the UK: a dense urban site in the centre of London and a residential suburban site in Swindon. Eddy covariance observations of the turbulent fluxes are used to assess model performance over a twoyear period (2011-2013). The distinct characteristics of the sites mean their surface energy exchanges differ considerably. The model suggests the largest differences can be attributed to surface cover (notably the proportion of vegetated versus impervious area) and the additional energy supplied by human activities. SUEWS performs better in summer than winter, and better at the suburban site than the dense urban site. One reason for this is the bias towards suburban summer field campaigns in observational data used to parameterise this (and other) model(s). The suitability of model parameters (such as albedo, energy use and water use) for the UK sites is considered and, where appropriate, alternative values are suggested. An alternative parameterisation for the surface conductance is implemented, which permits greater soil moisture deficits before evaporation is restricted at non-irrigated sites. Accounting for seasonal variation in the estimation of storage heat flux is necessary to obtain realistic wintertime fluxes.

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The objective of this study was to investigate the role of environmental factors in sleep duration among adolescents living in rural areas. A total of 1140 students (569 males), aged 10-19 years, and attending two schools in rural regions in southern Brazil, completed a questionnaire about their sleep habits. Demographic data were also obtained. Prevalence ratios (PR) were estimated for the cases of more than 9 h of sleep on weekdays. Sleep duration in adolescents with and without electric lighting at home was analyzed. Average sleep duration at night was 9.63 (1.64) h on school-going days and 10.14 (2.42) h on weekends. The prevalence of adolescents sleeping for more than 9 h at night on school-going days was 58.3%. Older adolescents showed a tendency to delay their sleep onset times, which is associated with a reduction of sleep duration. Adolescents without electric lighting at home slept longer on school-going days (P < 0.001) and on weekends (P = 0.013) when compared to those with electric lighting at home. From multivariate analysis, age (P < 0.001), school schedule (P = 0.007) and work (0.042) were factors affecting sleep duration. In contrast to the data previously reported for urban populations, we found a high prevalence of adolescents sleeping for more than 9 h on school nights. Data on populations living in less industrialized regions reinforce the idea that technological advances are associated with the negative impact of sleep phase delay in adolescents.

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Deforestation in Brazilian Amazonia accounts for a disproportionate global scale fraction of both carbon emissions from biomass burning and biodiversity erosion through habitat loss. Here we use field- and remote-sensing data to examine the effects of private landholding size on the amount and type of forest cover retained within economically active rural properties in an aging southern Amazonian deforestation frontier. Data on both upland and riparian forest cover from a survey of 300 rural properties indicated that 49.4% (SD = 29.0%) of the total forest cover was maintained as of 2007. and that property size is a key regional-scale determinant of patterns of deforestation and land-use change. Small properties (<= 150 ha) retained a lower proportion of forest (20.7%, SD = 17.6) than did large properties (>150 ha; 55.6%, SD = 27.2). Generalized linear models showed that property size had a positive effect on remaining areas of both upland and total forest cover. Using a Landsat time-series, the age of first clear-cutting that could be mapped within the boundaries of each property had a negative effect on the proportion of upland, riparian, and total forest cover retained. Based on these data, we show contrasts in land-use strategies between smallholders and largeholders, as well as differences in compliance with legal requirements in relation to minimum forest cover set-asides within private landholdings. This suggests that property size structure must be explicitly considered in landscape-scale conservation planning initiatives guiding agro-pastoral frontier expansion into remaining areas of tropical forest. (C) 2010 Elsevier Ltd. All rights reserved.

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A comparison of dengue virus (DENV) antibody levels in paired serum samples collected from predominantly DENV-naive residents in an agricultural settlement in Brazilian Amazonia (baseline seroprevalence, 18.3%) showed a seroconversion rate of 3.67 episodes/100 person-years at risk during 12 months of follow-up. Multivariate analysis identified male sex, poverty, and migration from extra-Amazonian states as significant predictors of baseline DENY seropositivity, whereas male sex, a history of clinical diagnosis of dengue fever, and travel to an urban area predicted subsequent seroconversion. The laboratory surveillance of acute febrile illnesses implemented at the study site and in a nearby town between 2004 and 2006 confirmed 11. DENV infections among 102 episodes studied with DENV IgM detection, reverse transcriptase-polymerise chain reaction, and virus isolation; DENV-3 was isolated. Because DENV exposure is associated with migration or travel, personal protection measures when visiting high-risk urban areas may reduce the incidence of DENV infection in this rural population.

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[1] The retrieval of aerosol optical depth (Ta) over land by satellite remote sensing is still a challenge when a high spatial resolution is required. This study presents a tool that uses satellite measurements to dynamically identify the aerosol optical model that best represents the optical properties of the aerosol present in the atmosphere. We use aerosol critical reflectance to identify the single scattering albedo of the aerosol layer. Two case studies show that the Sao Paulo region can have different aerosol properties and demonstrates how the dynamic methodology works to identify those differences to obtain a better T a retrieval. The methodology assigned the high single scattering albedo aerosol model (pi o( lambda = 0.55) = 0.90) to the case where the aerosol source was dominated by biomass burning and the lower pi(o) model (pi(o) (lambda = 0.55) = 0.85) to the case where the local urban aerosol had the dominant influence on the region, as expected. The dynamic methodology was applied using cloud-free data from 2002 to 2005 in order to retrieve Ta with Moderate Resolution Imaging Spectroradiometer ( MODIS). These results were compared with collocated data measured by AERONET in Sao Paulo. The comparison shows better results when the dynamic methodology using two aerosol optical models is applied (slope 1.06 +/- 0.08 offset 0.01 +/- 0.02 r(2) 0.6) than when a single and fixed aerosol model is used (slope 1.48 +/- 0.11 and offset - 0.03 +/- 0.03 r(2) 0.6). In conclusion the dynamical methodology is shown to work well with two aerosol models. Further studies are necessary to evaluate the methodology in other regions and under different conditions.

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Background: The rat has been a mainstay of physiological and metabolic research, and more recently mice. This study aimed at characterizing the postprandial triglyceride profile of two members of the Muridae family: the Wistar rats (Rattus norvegicus albinus) and C57BL/6 mice (Mus musculus) plus comparing them to the profile obtained in humans. Methods: Thirty-one male and twelve female Wistar rats, ten C57BL/6 male and nine female mice received a liquid meal containing fat (17%), protein (4%) and carbohydrates (4%), providing 2 g fat/Kg. Thirty-one men and twenty-nine women received a standardized liquid meal containing fat (25%), dextromaltose (55%), protein (14%), and vitamins and minerals (6%), and providing 40 g of fat per square meter of body surface. Serial blood samples were collected at 2, 4, 6, 8 and 10 h after the ingestion in rats, at 1, 2, 3, 4, 5 and 6 h in mice and in humans at 2, 4, 6 and 8 h. Wilcoxon and Mann-Whitney tests were used. Results/Discussion: The triglyceride responses were evaluated after the oral fat loads. Fasting and postprandial triglyceridemia were determined sequentially in blood sample. AUC, AUIC, AR, RR and late peaks were determined. Conclusions: Rats are prone to respond in a pro-atherogenic manner. The responses in mice were closer to the ones in healthy men. This study presents striking differences in postprandial triglycerides patterns between rats and mice not correlated to baseline triglycerides, the animal baseline body weight or fat load in all animal groups.

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The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population patronize the nearest facility and that the distance between the resident and the facility may be measured by the Euclidean distance. Carling, Han, and Håkansson (2012) compared two network distances with the Euclidean in a rural region witha sparse, heterogeneous network and a non-symmetric distribution of thepopulation. For a coarse network and P small, they found, in contrast to the literature, the Euclidean distance to be problematic. In this paper we extend their work by use of a refined network and study systematically the case when P is of varying size (2-100 facilities). We find that the network distance give as gooda solution as the travel-time network. The Euclidean distance gives solutions some 2-7 per cent worse than the network distances, and the solutions deteriorate with increasing P. Our conclusions extend to intra-urban location problems.

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A história recente do Nordeste caracteriza-se por uma primeira fase de isolamento e outra de articulação. Nessa segunda fase, o dinamismo que se instala a partir da década de sessenta provocou profundas transformações na economia da região. Essas transformações implicaram em elevadas taxas de expansão do produto regional, alterações na estrutura produtiva através da adoção de novos processos de trabalho que implicou de um lado, na redução da demanda por trabalho e de outro, na sua expansão. Registrou-se, também, mudanças bastante significativas nos gêneros industriais reduzindo a participação na produção das indústrias de bens de consumo não-duráveis e aumentando de modo importante a participação das indústrias de bens intermediários voltadas para o mercado nacional e internacional, o que contribui para aumentar a dependência do Nordeste em relação as regiões mais ricas. As mudanças iniciadas no setor industrial se propagam para os setores primários, secundários e terciários. No setor agrícola, as transformações dificultaram a sobrevivência do trabalhador, ampliaram as relações capitalistas no setor manifestas na maior proletarização da mão-de-obra rural; estimularam as emigrações para. as cidades e elevaram consideravelmente a participação da população ocupada em atividades predominantemente urbanas. No setor terciário, as mudanças provocaram o incremento do subemprego, grande diferenciação nos 11 níveis de produtividade e rendimentos, gerando um quadro de aprofundamento da heterogeneidadeda estrutura produtiva e do mercado de trabalho. Adicionalmente, houve uma excessiva urbanização, aumento da concentração da renda, incremento do grau de informalidade, crescimento do número de empregados clandestinos e maior participação dos menores e adultos no mercado de trabalho. Tudo isso, ocorreu,associado ao quadro de dinamismo das atividades produtivas, sem paralelo na história recente das regiões atrasadas do pais. A análise dos dados também mostrou que o nível do desemprego aberto, é relativamente baixo tanto para os homens como para as mulheres. Isto ocorre porque na expansão ou na retração econômica as flutuações no nível de ocupação são acampanhadas por modificações da taxa de participação da PIA no mercado de trabalho. Portanto, a recente infonnalidade, fonnalidade e submersão da mão-de-obra no Nordeste estão associadas a um contexto de crescimento da economia e, por conseguinte, resultam do estilo ou padrão de acumulação de capital que, mesmo se realizando com altas taxas de expansão, não repercute positivamente no mercado de trabalho, nos tennos requeridos pela oferta de mão-de-obra. Assim, o aparecimento de um excedente relativo de população é resultado do padrão de acumulação da capital da economia regional, que está associado ao modo como o Nordeste se inseriu no contexto nacional e, nesse sentido, é o padrão de industrialização o principal fator responsável por parte importante do insucesso da economia local em absorver produtivamente a população que se apresenta no mercado de trabalho urbano

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This paper estimates the effect of lighting on violent crime reduction. We explore an electrification program (LUZ PARA TODOS or Light for All - LPT) adopted by the federal government to expand electrification to rural areas in all Brazilian municipalities in the 2000s as an exogenous source of variation in electrification expansion. Our instrumental variable results show a reduction in homicide rates (approximately five homicides per 100,000 inhabitants) on rural roads/urban streets when a municipality moved from no access to full coverage of electricity between 2000 and 2010. These findings are even more significant in the northern and northeastern regions of Brazil, where rates of electrification are lower than those of the rest of the country and, thus, where the program is concentrated. In the north (northeast), the number of violent deaths on the streets per 100,000 inhabitants decreased by 48.12 (13.43). This moved a municipality at the 99th percentile (75th) to the median (zero) of the crime distribution of municipalities. Finally, we do not find effects on violent deaths in households and at other locations. Because we use an IV strategy by exploring the LPT program eligibility criteria, we can interpret the results as the estimated impact of the program on those experiencing an increase in electricity coverage due to their program eligibility. Thus, the results represent local average treatment effects of lighting on homicides.

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OBJETIVO: avaliar a sintomatologia climatérica e fatores relacionados entre mulheres dos meios urbano e rural do Rio Grande do Norte. MÉTODOS: estudo transversal, descritivo, envolvendo casuística de 261 mulheres climatéricas residentes em Natal e Mossoró (grupo urbano; n=130) e Uruaçu, em São Gonçalo do Amarante (grupo rural; n=131). A sintomatologia climatérica foi avaliada pelo Índice Menopausal de Blatt-Kupperman (IMBK) e Escala Climatérica de Greene (ECG). A análise estatística constou de comparações das medianas dos escores entre os grupos e regressão logística. Defi niram-se como “muito sintomáticas” as pacientes com escores ≥20, para ambos instrumentos (variável dependente). As variáveis independentes foram: idade, procedência, alfabetização, obesidade e prática de atividade física. RESULTADOS: o grupo urbano apresentou escores signifi cativamente superiores ao grupo rural, tanto para o IMBK (medianas de 26,0 e 17,0, respectivamente; p<0,0001), quanto para a ECG (medianas de 27,0 e 16,0, respectivamente; p<0,0001). Na amostra total, evidenciou-se que 56,3% (n=147) das mulheres foram classifi cadas como “muito sintomáticas”. Na comparação intergrupos, essa prevalência foi signifi cativamente mais elevada nas mulheres urbanas em relação às rurais (79,2 e 33,6%, respectivamente; p<0,05). Pela análise de regressão logística, evidenciou-se que a chance de pertencer ao grupo defi nido como “muito sintomáticas” foi maior para mulheres do meio urbano [odds ratio ajustado (OR)=7,1; 95% intervalo de confi ança a 95% (IC95%)=3,69-13,66] e alfabetizadas (OR=2,19; IC95%=1,16-4,13). A idade superior a 60 anos associou-se com menor chance de ocorrência de sintomas signifi cativos (OR=0,38; IC95%=0,17-0,87). CONCLUSÕES: a prevalência de sintomas climatéricos signifi cativos é menor em mulheres do meio rural, demonstrando que fatores socioculturais e ambientais estão fortemente relacionados ao surgimento dos sintomas climatéricos em nossa população.___________________________________ABSTRACT PURPOSE: to evaluate climacteric symptoms and related factors in women living in rural and urban areas of Rio Grande do Norte, Brazil. METHODS: a cross-sectional study involving 261 women in the climacteric was performed. A total of 130 women from Natal and Mossoró (urban group) and 131 from Uruaçu, in São Gonçalo do Amarante (rural group), were studied. Climacteric symptoms were assessed by the Blatt-Kupperman Menopausal Index (BKMI) and Greene Climacteric Scale (GCE). Statistical analysis involved comparison of median between groups and logistic regression analysis. Patients were defi ned as “very symptomatic” when the climacteric score was ≥20 for both questionnaires (dependent variable). Independent variables were: age, living area, schooling, obesity and physical activity. RESULTS: the urban group had signifi cantly higher scores than those of the rural group, both for BKMI (median of 26.0 and 17.0, respectively; p<0.0001) and for GCE (median of 27.0 and 16.0, respectively; p<0.0001). For the entire sample, a total of 56.3% (n=147) of the women were classifi ed as “very symptomatic”. This prevalence was signifi cantly higher in urban than in rural women (79.2 and 33.6%, respectively; p<0.05). Logistic regression analysis showed that the likelihood of belonging to the group defi ned as “very symptomatic” was greater for urban women [adjusted odds ratio (OR)=7.1; confi dence interval at 95% (95%CI)=3.69-13.66] who were literate (OR=2.19; 95%CI=1.16- 4.13). Individuals over the age of 60 years had less chance of having signifi cant symptoms (OR=0.38; 95%CI=0.17-0.87). CONCLUSIONS: the prevalence of signifi cant climacteric symptoms is less in women from a rural environment, showing that sociocultural and environmental factors are strongly related to the appearance of climacteric symptoms in our population

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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This study deals with the rural social security Universalist established by the Constitution of 1988 and its importance in the economy of the municipalities of Rio Grande do Norte. In this context, the study seeks to satisfy two important criteria that guide the selection of objects of social science research: a consideration of issues that have relevance to the real world and the intention to make the contribution to the scholarly literature on theoretical and empirical aspects. The research seeks to reveal what is the economic importance of the subsystem of social security for rural municipalities in RN. The hypothesis is that the transfer of income received by beneficiaries from the rural social security tax exceeds the explicit mechanisms for most municipalities in RN, in many cases significantly, proving the importance of this policy as a mechanism for combating poverty and reducing social inequality, especially before the fragility of the federal system on the national political entity hall. The study presents theoretical cores - chapters 1-3 - and empirical - Chapter 4. The first core is about the evolution of social protection as a state policy, addressing the influential theories and typologies of the State of Social Welfare and the characteristics of the Brazilian social security model, but mainly, its rural social security subsystem, its history until universalistic model inaugurated by the Federal Constitution of 1988. The second begins with an overview of studies that have emphasized the impact of Social Security on the local economy of small municipalities, then passing data and statistics in order to gauge the socioeconomic importance of pension income in the rural municipalities of Rio Grande do Norte. To this end, the final chapter provides a comparison of the monetary value transferred by the payment of social security benefits - rural and urban - to each of the 167 municipalities in RN with the equally important sources of income in the budget of municipal entities. Apart from their own tax revenues, are objects of comparison with the value of pension benefits awarded in RN, transfer quota state relating to the municipality on the federal ICMS and the transfer on the FPM

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Cet article étudie le livre de visites de l'ancienne école mixte de la Fazenda Ponte Alta/Bela Vista, liée au groupe scolaire de la ville de Bariri, dans l'état de São Paulo (SP). À partir des registres de vingt ans d'activités (1928-1948), nous retraçons les exigences des inspecteurs primaires et si ces exigences provenaient (ou non) de professeurs et de la communauté paysanne pour ébaucher un cadre socio-historique de l'enseignement des premières lettres dans la zone rurale de l'intérieur de l'état de São Paulo. Il en résulte que le discours qui défendait l'égalité de chances pour les populations urbaines et rurales négligeait généralement le besoin de promouvoir l'égalité de conditions pour que la communauté rurale puisse profiter des chances qui lui étaient promises.