960 resultados para Peri-urban estuaries


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Harmonious territorial development and urban-rural linkages have attracted increased policy attention in recent years in the attempt to overcome the predominant discourse of the urban-rural divide. Territorial development refers to a ‘process through which the geographies of territories inhabited by human societies is progressively transformed. It involves physical components (infrastructure, landscapes and townscapes, etc.) but also the territorial structure of settlements pattern, i.e. the geographic distribution of population and human activities’ (Council of Europe, 2007). Urban-rural linkages refer to ‘complementary and synergetic functions and flows of people, natural resources, capital, goods, employment, ecosystem services, information and technology between rural, peri-urban and urban areas’ (UN-HABITAT, 2015). ‘Urban-rural partnership is the mechanism of cooperation that manages linkages to reach common goals and enhance urban-rural linkages’ (OECD, 2013). Therefore, territorial or urban-rural partnerships are increasingly regarded as a desirable policy action, respectful of the particular identities of different territorial components (UCLG, 2016).

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Rheumatic heart disease (RHD) is the largest cardiac cause of morbidity and mortality in the world's youth. Early detection of RHD through echocardiographic screening in asymptomatic children may identify an early stage of disease, when secondary prophylaxis has the greatest chance of stopping disease progression. Latent RHD signifies echocardiographic evidence of RHD with no known history of acute rheumatic fever and no clinical symptoms.

OBJECTIVE: Determine the prevalence of latent RHD among children ages 5-16 in Lilongwe, Malawi.

DESIGN: This is a cross-sectional study in which children ages 5 through 16 were screened for RHD using echocardiography.

SETTING: Screening was conducted in 3 schools and surrounding communities in the Lilongwe district of Malawi between February and April 2014.

OUTCOME MEASURES: Children were diagnosed as having no, borderline, or definite RHD as defined by World Heart Federation criteria. The primary reader completed offline reads of all studies. A second reader reviewed all of the studies diagnosed as RHD, plus a selection of normal studies. A third reader served as tiebreaker for discordant diagnoses. The distribution of results was compared between gender, location, and age categories using Fisher's exact test.

RESULTS: The prevalence of latent RHD was 3.4% (95% CI = 2.45, 4.31), with 0.7% definite RHD and 2.7% borderline RHD. There was no significant differences in prevalence between gender (P = .44), site (P = .6), urban vs. peri-urban (P = .75), or age (P = .79). Of those with definite RHD, all were diagnosed because of pathologic mitral regurgitation (MR) and 2 morphologic features of the mitral valve. Of those with borderline RHD, most met the criteria by having pathological MR (92.3%).

CONCLUSION: Malawi has a high rate of latent RHD, which is consistent with other results from sub-Saharan Africa. This study strongly supports the need for a RHD prevention and control program in Malawi.

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This paper addresses current changes in the highly diverse European landscape, and the way these transitions are being treated in policy and landscape management in the fragmented, heterogeneous and dynamic context of today’s Europe. It appears that intersecting driving forces are increasing the complexity of European landscapes and causing polarising developments in agricultural land use, biodiversity conservation and cultural landscape management. On the one hand, multifunctional rural landscapes, especially in peri-urban regions, provide services and functions that serve the citizens in their demand for identity, support their sense of belonging and offer opportunities for recreation and involvement in practical landscape management. On the other hand, industrial agricultural production on increasingly large farms produces food, feed, fibre and energy to serve expanding international markets with rural live ability and accessibility as a minor issue. The intermediate areas of traditionally dominant small and family farms in Europe seem to be gradually declining in profitability. The paper discusses the potential of a governance approach that can cope with the requirement of optimising land-sharing conditions and community-based landscape development, while adapting to global market conditions.

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Leishmaniasis are endemic diseases wild spread in the New and Old World, caused by the flagelated protozoan Leishmania. In the New World, the distribution of different forms of leishmaniasis is mostly in tropical regions. In the State of Rio Grande do Norte, Northeast Brazil, 85% of the captured sand flies fauna is Lutzomyia longipalpis. The distribution of the sand fly vector in the state overlaps with the disease distribution, where the presence of sand flies is associated with presence of animals shelters. The aim of this study was to analyse the blood meal preference of sand flies vector from the genus Lutzomyia spp. in laboratory conditions, to verify the vector life cicle at different temperatures sets and to identify the main blood meal source in endemic areas for visceral leishmaniasis (VL) at peri-urban regions of Natal. Sand flies samples were collected from the municipalities of São Gonçalo do Amarante and Nísia Floresta where female sand flies were grouped for the colony maintenance in the laboratory and for the analysis of the preferred source of sand fly blood meal in natural environment. The prevalence of blood meal preference and oviposition for the females sand flies was 97% for Cavia porcellus with oviposition of 19 eggs/female; 97% for Eqqus caballus with 19 eggs/female; 98% for human blood with 14 eggs/female; 71.3% for Didelphis albiventris with 8.4 eggs/female; 73% for Gallus gallus with 14 eggs/female; 86% for Canis familiaris with 10.3 eggs/female; 81.4% for Galea spixii with 26 eggs/female; 36% for Callithrix jachus with 15 eggs/female; 42.8% for Monodelphis domestica with 0% of oviposition. Female sand flies did not take a blood meal from Felis catus. Sand flies life cycle ranged from 32-40 days, with 21-50 oviposition rates approximately. This study also showed that at 32°C the life cycle had 31 days, at 28° C it had 50 days and at 22°C it increased to 79 days. Adjusting the temperature to 35°C the eggs did not hatch, thus blocking the life cycle. A total of 1540 sand flies were captured, among them, 1.310 were male and 230 were female. Whereas 86% of the sand flies captured were Lu. longipalpis as compared to 10.5% for Lu. evandroi and, 3.2% for L. lenti and 0.3% for Lu whitmani. The ratio between female and male sandfly was approximately 6 males to 1 female. In Nísia Floresta, 50.7% of the collected females took their blood meal from armadillo, 12.8% from human. Among the female sand flies captured in São Gonçalo do Amarante, 80 of them were tested for the Leishmania KDNA infectivity where 5% of them were infected with Leishmania chagasi. Female Lutzomyia spp. showed to have an opportunistic blood meal characteristic. The behavioral parameters seem to have a higher influence in the oviposition when compared to the level of total proteins detected in the host s bloodstream. A higher Lu. longipalpis life cycle viability was observed at 28°C. The increase of temperature dropped the life cycle time, which means that the life cycle is modified by temperature range, source of blood meal and humidity. Lu longipalpis was the most specie found in the inner and peridomiciliar environment. In Nísia Floresta, armadillos were the main source of blood meal for Lutzomyia spp. At São Gonçalo do Amarante, humans were the main source of blood meal due to CDC nets placed inside their houses

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Os espaços verdes públicos urbanos são muito importantes no contexto urbano. Influenciam de diversas formas na qualidade de vida das populações, proporcionando benefícios ambientais, sociais e econômicos. A fim de avaliar a disponibilidade destes espaços na cidade de Bragança, foram realizadas análises utilizando indicadores, com apoio dos software ArcGIS 9.3 e QGis 2.14.0-Essen, que permitiram avaliar a oferta destes espaços nas suas diferentes tipologias e categorias dimensionais. Para o efeito foram aplicados os indicadores: Percentagem de espaços verdes, Espaços verdes per capita, Distância média, Índice de Área Verde por Área de Implantação e Índice de Área Verde por Área Coberta. Posteriormente, procedeu-se à aplicação de inquéritos a fim de avaliar as perceções e atitudes de uma amostra da população de Bragança, realizando análises descritivas e estatísticas, com recurso ao software SPSS17, buscando descrever a atual relação com os espaços verdes e usando testes não paramétricos para identificar diferenças entre subgrupos da amostra, numa análise centrada em dois níveis: a escala urbana e a escala de Bairro. Procurando avaliar possíveis alterações futuras, foram testados cenários realistas, um correspondendo à introdução de espaços verdes em terrenos na posse da Autarquia e outro considerando a ampliação das áreas verdes previstas no Plano de Urbanização de Bragança de 2010. Os Resultados permitiram identificar diferenças relevantes na oferta de espaços verdes da cidade. Aplicando os indicadores foi possível verificar que existe a concentração de espaços verdes de maior dimensão na zona central da cidade, denotando um claro desequilíbrio na introdução de novos espaços em zonas de expansão urbana. Os inquéritos aplicados possibilitaram constatar que os inquiridos que possuem maior disponibilidade de espaços verdes em seu bairro de residência apresentam respostas mais satisfatórias em relação a acessibilidade e a aparência visual e paisagística dos bairros. Da análise de cenários resulta que com a implantação de novos espaços verdes, para as duas análises, ocorreria uma melhoria da oferta e distribuição dos espaços verdes na cidade permitindo um maior reequilíbrio face à concentração na zona central, melhorando a acessibilidade para toda a população.

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Dissertação para obtenção do grau de Mestre em Arquitectura com especialização em Urbanismo, apresentada na Universidade de Lisboa - Faculdade de Arquitetura. Assuntos:

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South Florida has been subject to considerable changes during the last 100 years. This study provides a detailed survey of the presence, concentration levels, and spatial distribution of organic and inorganic contaminants in sediment samples collected within the coastal environments of southwest Florida. It evaluates the potential contributions and effects of the urban and agricultural development to the pollution loading of the estuarine sediments. And it also provides information regarding chronology of contamination at impacted sites. Copper was found to be the most critical contaminant among the trace metals. 12% of the samples exceeded the Threshold Effects Level (TEL). None of organic contaminants measured exceeded the Probable Effects Level (PEL) criteria. Total PAHs concentrations exceeded the TEL criteria in 6% of the samples. The evaluation for the chronology of contamination showed a significant increase with time of every contaminant analyzed. Fluorescence spectroscopy proves to be a good method for fast screening PAHs.

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The urban waterfront may be regarded as the littoral frontier of human settlement. Typically, over the years, it advances, sometimes retreats, where terrestrial and aquatic processes interact and frequently contest this margin of occupation. Because most towns and cities are sited beside water bodies, many of these urban centers on or close to the sea, their physical expansion is constrained by the existence of aquatic areas in one or more directions from the core. It is usually much easier for new urban development to occur along or inland from the waterfront. Where other physical constraints, such as rugged hills or mountains, make expansion difficult or expensive, building at greater densities or construction on steep slopes is a common response. This kind of development, though technically feasible, is usually more expensive than construction on level or gently sloping land, however. Moreover, there are many reasons for developing along the shore or riverfront in preference to using sites further inland. The high cost of developing existing dry land that presents serious construction difficulties is one reason for creating new land from adjacent areas that are permanently or periodically under water. Another reason is the relatively high value of artificially created land close to the urban centre when compared with the value of existing developable space at a greater distance inland. The creation of space for development is not the only motivation for urban expansion into aquatic areas. Commonly, urban places on the margins of the sea, estuaries, rivers or great lakes are, or were once, ports where shipping played an important role in the economy. The demand for deep waterfronts to allow ships to berth and for adjacent space to accommodate various port facilities has encouraged the advance of the urban land area across marginal shallows in ports around the world. The space and locational demands of port related industry and commerce, too, have contributed to this process. Often closely related to these developments is the generation of waste, including domestic refuse, unwanted industrial by-products, site formation and demolition debris and harbor dredgings. From ancient times, the foreshore has been used as a disposal area for waste from nearby settlements, a practice that continues on a huge scale today. Land formed in this way has long been used for urban development, despite problems that can arise from the nature of the dumped material and the way in which it is deposited. Disposal of waste material is a major factor in the creation of new urban land. Pollution of the foreshore and other water margin wetlands in this way encouraged the idea that the reclamation of these areas may be desirable on public health grounds. With reference to examples from various parts of the world, the historical development of the urban littoral frontier and its effects on the morphology and character of towns and cities are illustrated and discussed. The threat of rising sea levels and the heritage value of many waterfront areas are other considerations that are addressed.

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High salinity estuaries in the southeastern U.S. have experienced increased inputs of contaminants from nonpoint source (NPS) urban runoff and decreases in habitat due to filling of wetlands and dock/bulkhead construction. Urbanization may pose significant risks to estuarine fauna, particularly crustaceans. The grass shrimp of the genus Palaemonetes, is one of the dominant species found in estuarine tidal creeks, accounting for greater than 50% of all macropelagic fauna on an annual basis. Spatial analytical and geographic information system techniques were used to determine which factors influenced the Palaemonetes population structures in a South Carolina bar-built estuary surrounded by urban development. Impacts from land use practices were investigated using concentric circular buffers around study sites. Factors investigated included sediment-associated polycyclic aromatic hydrocarbons concentration, land use classification, percent impervious surfaces, and other selected urban factors. Geographic information system and statistical modeling showed quantitative relationships between land use class and impacts on Palaemonetes density. The study suggests that habitat loss is a major factor influencing grass shrimp densities. Multiple regression modeling suggests a significant relationship between habitat alterations and Palaemonetes densities.

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Calanoid copepod nauplii hatched from intertidal sediment samples from 3 British estuaries, the Exe, the Humber and the Mersey. The Exe Estuary is exposed to low levels of urban and agricultural pollution but the Humber and Mersey are subject to more extensive urban and industrial pollution. Samples were taken from the Humber and the Exe in April and November 1995 and from the Mersey and the Exe in June and October 1995. The concentrations of polycyclic aromatic hydrocarbons (PAH) in the sediments were measured as an index of pollution. The PAH concentrations in sediment were lowest in the Exe (mean <100 mu g/g dry weight) with most values >200 mu g/g dry weight in the Humber and some >300 mu g/g dry weight in the Mersey. Many more nauplii hatched from incubated sediments from the Exe than from the more polluted estuaries in April, June and November but larger numbers of nauplii hatched from the samples from the Mersey than from the Exe in October. Eggs were extracted from the samples taken in October and November and incubated; 92% of those from the Exe, 48% of those from the Humber and 14% of those from the Mersey hatched. This is consistent with reduction in viability of eggs with increased pollution. The viability of copepod eggs from sediments appears to have potential as a technique for in situ bioassay of fine sediments.

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The impact of urban waste-water and non-point nitrate discharges in estuarine and near-shore coastal waters are analyzed. The study is focused on the effects of applying the European directives 91/271/EEC and 91/676/EEC to these systems. 4 Portuguese estuaries and two coastal lagoons with different characteristics are studied. A modelling system is applied and calibrated in each system. Three nitrate load scenarios are examined. It is shown that the morphologic and hydrodynamic characteristics of the domain largely control the ecological processes in these systems. The primary production limitation factors are split into “biologic” and “hydrodynamic” components. The physical limitation due to hydrodynamic and residence time is the most important factor. The combined limitation of “biologic” factors (temperature, light and nutrients availability) control productivity only in the systems where physical limitation is not important.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Carbon and nitrogen loading to streams and rivers contributes to eutrophication as well as greenhouse gas (GHG) production in streams, rivers and estuaries. My dissertation consists of three research chapters, which examine interactions and potential trade-offs between water quality and greenhouse gas production in urban streams of the Chesapeake Bay watershed. My first research project focused on drivers of carbon export and quality in an urbanized river. I found that watershed carbon sources (soils and leaves) contributed more than in-stream production to overall carbon export, but that periods of high in-stream productivity were important over seasonal and daily timescales. My second research chapter examined the influence of urban storm-water and sanitary infrastructure on dissolved and gaseous carbon and nitrogen concentrations in headwater streams. Gases (CO2, CH4, and N2O) were consistently super-saturated throughout the course of a year. N2O concentrations in streams draining septic systems were within the high range of previously published values. Total dissolved nitrogen concentration was positively correlated with CO2 and N2O and negatively correlated with CH4. My third research chapter examined a long-term (15-year) record of GHG emissions from soils in rural forests, urban forest, and urban lawns in Baltimore, MD. CO2, CH4, and N2O emissions showed positive correlations with temperature at each site. Lawns were a net source of CH4 + N2O, whereas forests were net sinks. Gross CO2 fluxes were also highest in lawns, in part due to elevated growing-season temperatures. While land cover influences GHG emissions from soils, the overall role of land cover on this flux is very small (< 0.5%) compared with gases released from anthropogenic sources, according to a recent GHG budget of the Baltimore metropolitan area, where this study took place.