983 resultados para virtual communities


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Poverty has been variously measured in terms of income, consumption, and access to social and physical infrastructures. It is a multi-component phenomenon that cannot be measured by one single variable. This indicates that poverty alleviation or eradication requires a holistic approach. Because the existing strategies at ensuring poverty alleviation have not made impact at the Lake Chad Basin. Therefore, this study identifies the strategies that are adaptable to the area. Data were obtained on Literacy, income, quality housing, mobility, and access to infrastructure, cultural and socio-economic. The paper develops a pragmatic strategy through which the fishing communities can experience true empowerment and improved standard of living

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Projects of the scope of the restoration of the Florida Everglades require substantial information regarding ecological mechanisms, and these are often poorly understood. We provide critical base knowledge for Everglades restoration by characterizing the existing vegetation communities of an Everglades remnant, describing how present and historic hydrology affect wetland vegetation community composition, and documenting change from communities described in previous studies. Vegetation biomass samples were collected along transects across Water Conservation Area 3A South (3AS).

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19 p.

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Thirty-nine participants from 18 countries, including women fishworkers, representatives of fishworker organizations and NGOs, activists and researchers, met at Mahabalipuram, India, during 7-10 July 2010, to discuss the theme “Recasting the Net: Defining a Gender Agenda for Sustaining Life and Livelihoods in Fishing Communities”. The workshop was meant to reflect on what needs to be done to develop a ‘gender agenda’ for sustaining life and livelihoods in fisheries. It was also organized against the backdrop of the growing international recognition of small-scale fisheries and efforts to enhance their contribution to food security and poverty alleviation, as evidenced in the deliberations of the the Committee on Fisheries (COFI) of the Food and Agriculture Organization of the United Nations (FAO). This publication—the proceedings of the Mahabalipuram workshop—will be useful for fishworker organizations, gender activists, researchers, policymakers, fish farmers, members of civil society and anyone interested in gender, fisheries and livelihoods. (PDF contains 89 pages)

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The likely response of freshwater plankton to the direct and indirect effects of sustained global warming are summarized. The increase in CO2 posited by climatologists will have a direct effect on many biological processes, and an even more important indirect effect on the global climate. Lake plankton populations are relatively well buffered against sudden fluctuations in temperature but can react in unexpected ways to seasonal changes in the wind speed, with effects on seasonal growth and succession of plankton. The direct

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Wales is important for fish conservation in Britain. In much of Wales, atchments are small (median catchment size = 121 km2 ) and frequently eparated by areas of upland (> 600 m altitude), creating a highly agmented habitat for freshwater fish. Consequently, fish communities onsist mainly of diadromous species such as trout, eel and sticklebacks hat were able to recolonise freshwaters via the sea following the retreat of he ice sheets ca. 10 000 years BP. This review aims to (i) update the former work of Lyle and Maitland, taking into account new National Nature Reserves (NNRs)and additional data collected since 1991; (ii) assess the different fish communities represented on Welsh NNRs with respect to their naturalness; (iii) examine the use of NNRs for angling; (iv) evaluate opportunities for expanding the NNR series to conserve fish populations of conservation importance. The paper provides a table of freshwater fish occurrence by water body in Wales.

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Ten year comparison of fish survey's with respect to diversity evenness and composition of fish communities. The upper Patuxent River was divided into Piedmont Plateau and Coastal Plain regions, not only for geographical purposes, but also because of the clustering of sewage treatment plants in the Coastal Plain region. In the Piedmont Plateau region, the fish species diversity changed very little from 1966 to 1977 ( Little Patuxent -- 2.82 to 2.66; Middle Patuxent -- 2.86 to 2.83; and main stem -- 2.46 to 2.63), except in a section of Little Patuxent River at and below the City of Columbia where the species diversity index showed a significant reduction from 2.97 to 1.99, and in a section of the main stem Patuxent River immediately downstream from the Brighton Dam of the Triadelphia Reservoir where the index increased significantly from 1.66 to 3.20. In the Coastal Plain region, a significant reduction in the fish species diversity index occurred between 1966 and 1977 below the two sewage treatment plant outfalls : Savage -- 2.69 to 0 and Patuxent-Crofton -- 3.06 to 1.33. Also, the substantial reduction in the species diversity index which had already occurred in 1966 below the six other plant: outfalls of Fort Meade No. I, Fort Meade No. 2, Maryland House of Correction, Maryland City , Parkway and Bowie, remained depressed in 1977. On the other hand, below the Horsepen Sewage Treatment Plant (a tertiary plant practicing dechlorination) the species diversity index increased from 1.91 to 2.8. (PDF contains 48 pages)

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Understanding the roles of microorganisms in environmental settings by linking phylogenetic identity to metabolic function is a key challenge in delineating their broad-scale impact and functional diversity throughout the biosphere. This work addresses and extends such questions in the context of marine methane seeps, which represent globally relevant conduits for an important greenhouse gas. Through the application and development of a range of culture-independent tools, novel habitats for methanotrophic microbial communities were identified, established settings were characterized in new ways, and potential past conditions amenable to methane-based metabolism were proposed. Biomass abundance and metabolic activity measures – both catabolic and anabolic – demonstrated that authigenic carbonates associated with seep environments retain methanotrophic activity, not only within high-flow seep settings but also in adjacent locations exhibiting no visual evidence of chemosynthetic communities. Across this newly extended habitat, microbial diversity surveys revealed archaeal assemblages that were shaped primarily by seepage activity level and bacterial assemblages influenced more substantially by physical substrate type. In order to reliably measure methane consumption rates in these and other methanotrophic settings, a novel method was developed that traces deuterium atoms from the methane substrate into aqueous medium and uses empirically established scaling factors linked to radiotracer rate techniques to arrive at absolute methane consumption values. Stable isotope probing metaproteomic investigations exposed an array of functional diversity both within and beyond methane oxidation- and sulfate reduction-linked metabolisms, identifying components of each proposed enzyme in both pathways. A core set of commonly occurring unannotated protein products was identified as promising targets for future biochemical investigation. Physicochemical and energetic principles governing anaerobic methane oxidation were incorporated into a reaction transport model that was applied to putative settings on ancient Mars. Many conditions enabled exergonic model reactions, marking the metabolism and its attendant biomarkers as potentially promising targets for future astrobiological investigations. This set of inter-related investigations targeting methane metabolism extends the known and potential habitat of methanotrophic microbial communities and provides a more detailed understanding of their activity and functional diversity.

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The zooplankton and macrobenthic communities of Lake Victoria were sampled by lift net and Ponar grab, respectively. The zooplankton comprised copepods and cladocerans, rotifers and aquatic insect larvae. Most taxa exhibited wide distribution in the lake, with the exception of rotifers which were rare in deep offshore waters. The main components in the macro-benthos were chaoborid and chironomid larvae and molluscs. Caridina nilotica (Roux) and other groups were rare in the samples. Zooplankton density ranged from 100000 or more to 4 million ind. m2 and increased from the shallow inshore to deep offshore waters. Numerical dominance of cyclopoids and nauplius larvae was a common feature at all stations sampled. Most macrobenthic taxa were also widely distributed, although chaoborid and chironomid larvae were rare in the samples. Rastrineobola argentea (Pellegrin) and larval Lates niloticus (L.) ate mainly cyclopoid copepods, while cichlids showed a strong preference for adult insects. High ecological stability of the cyclopoids, and the zooplankton community in general, despite radical ecosystem changes in recent years, coupled with what appears to be high predation pressure, offers good prospects for the pelagic fishery in the lake.

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For conservations of nature to be effective. there must be an understanding of what is present to be conserved. Thus in order to conserve the communites of the Cumbrian rivers, there must first be surveys to determine the spp present and their relative numbers. This has been carried out for many years, by a number of workers. It has been shown that the communities present are influenced by the substratum, the flow, the chemicals present, water temp and predation. Findings of the work on the River Lune were given at a seminar on the rivers of north-west Europe, held at Amiens in November, 1975. The proceedings of the seminar are to appear in special numbers of Bulletin francais de Pisciculure.

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This article describes the progress of the River Communities Project which commenced in 1977. This project aimed to develop a sensitive and practical system for river site classification using macroinvertebrates as an objective means of appraising the status of British rivers. The relationship between physical and chemical features of sites and their biological communities were examined. Sampling was undertaken on 41 British rivers. Ordination techniques were used to analyze data and the sites were classified into 16 groups using multiple discrimination analysis. The potential for using the environmental data to predict to which group a site belonged and the fauna likely to be present was investigated.

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Part I

Present experimental data on nucleon-antinucleon scattering allow a study of the possibility of a phase transition in a nucleon-antinucleon gas at high temperature. Estimates can be made of the general behavior of the elastic phase shifts without resorting to theoretical derivation. A phase transition which separates nucleons from antinucleons is found at about 280 MeV in the approximation of the second virial coefficient to the free energy of the gas.

Part II

The parton model is used to derive scaling laws for the hadrons observed in deep inelastic electron-nucleon scattering which lie in the fragmentation region of the virtual photon. Scaling relations are obtained in the Bjorken and Regge regions. It is proposed that the distribution functions become independent of both q2 and ν where the Bjorken and Regge regions overlap. The quark density functions are discussed in the limit x→1 for the nucleon octet and the pseudoscalar mesons. Under certain plausible assumptions it is found that only one or two quarks of the six types of quarks and antiquarks have an appreciable density function in the limit x→1. This has implications for the quark fragmentation functions near the large momentum boundary of their fragmentation region. These results are used to propose a method of measuring the proton and neutron quark density functions for all x by making measurements on inclusively produced hadrons in electroproduction only. Implications are also discussed for the hadrons produced in electron-positron annihilation.

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Esta dissertação tem como objetivo analisar a intervenção de elementos linguísticos no processo leitor em espanhol como língua estrangeira (E/LE) ,em ambiente virtual, de docente desse idioma. A partir desse objetivo macro, estabelecemos um recorte e nos focamos na análise de como/se elementos linguísticos mais característicos de uma linguagem coloquial podem afetar mais a leitura de um docente de E/LE que teve na sua formação e na sua atividade profissional um contato maior com a língua formal. Nesse contexto, escolhemos o blog como o suporte virtual dos textos a serem lidos pelo sujeito por apresentar uma linguagem mais coloquial. No que se refere ao aporte teórico, esta pesquisa tem com principais bases a Linguística Textual (KOCH, 2009, 2002, 2007; KOCH ; TRAVAGLIA, 1996, 2000) e a leitura sócio-interacional (KATO, 1986, 2007; KLEIMAN, 1993, 1996, 2008; NUNES, 2005; VERGNANO-JUNGER, 2009). Também utilizamos alguns elementos da Análise do Discurso de base enunciativa em pontos nos quais ela dialoga com a perspectiva sócio-interacional, como, por exemplo, na noção de gênero do discurso (MAINGUENEAU, 1996, 2003; BAKTHIN, 2003). A Sociolinguística (MORENO FERNANDÉZ, 1996; ALKMIN, 2001) contribuiu para estabelecer os parâmetros da língua coloquial e formal. Quanto à leitura em ambiente virtual, seguimos Ribeiro (2005), Marcuschi (2007), Santaella (2008) e Vergnano-Junger (2009). Para a elaboração deste trabalho, utilizamos uma metodologia híbrida composta de uma parte documental e de um estudo de caso. A fase documental teve como metas classificar os blogs de docentes de E/LE e selecionar dois para a elaboração de atividades de leitura guiada. O estudo de caso realizado com um docente de E/LE, por sua vez, teve como etapas uma leitura livre, duas guiadas e uma entrevista. Objetivou observar e discutir o perfil e o processo leitor do sujeito, com foco na intervenção de elementos linguísticos. Dos resultados obtidos, podemos destacar uma proposta de classificação dos blogs de professores de E/LE. Com base no estudo de caso, duas considerações merecem destaque: (a) uma maior dificuldade de leitura do texto coloquial, ao que tudo indica, gerada pela variedade lexical e (b) uma tendência do sujeito à leitura linear em ambiente virtual, com atenção voltada, frequentemente, para os aspectos de vocabulário e como esses afetavam a compreensão, demonstrando uma tendência à leitura decodificadora