Diagnóstico do meio físico da bacia hidrográfica do Rio do Imbé - RJ: aplicação de metodologia integrada como subsídio ao manejo de microbacias.

O Diagnóstico do Meio Físico da Bacia do Rio do Imbé (BHRI) integra os estudos que subsidiam o projeto Manejo Sustentável de Recursos Naturais em Microbacias do Norte-Noroeste Fluminense - SMH-SEAAPI/GEF (Global Enviroment Facility), cujo principal objetivo é apoiar produtores rurais de base familiar na autogestão dos recursos naturais, visando o desenvolvimento rural baseado em um modelo de agricultura socioambientalmente sustentável. A metodologia adotada partiu da integração da base cartográfica e dos dados digitais de mapeamentos temáticos do meio físico (clima, recursos hídricos, geologia, geomorfologia, solos e uso e ocupação das terras). Adotou-se no presente estudo a escala 1:250.000, compatível com a maioria dos dados secundários, que foram transformados para uma mesma projeção cartográfica e inseridos em uma base de dados digital. Inicialmente, foi realizada a síntese dos dados de solos e geomorfologia para a identificação e delimitação de unidades morfopedológicas. Em seguida, essas unidades foram agrupadas em seis zonas agroecológicas, considerando as potencialidades e fragilidades dos recursos naturais, os padrões de uso e o estado de degradação das terras. As zonas foram descritas e caracterizadas com base no conjunto de dados temáticos disponível e complementados com as informações levantadas em campo. O trabalho de campo foi orientado para verificação da diversidade dos aspectos físicos, das atividades antrópicas e dos problemas de degradação e conflitos relacionados ao uso dos recursos naturais. Foram considerados ainda o histórico socioeconômico e ambiental da região e a percepção dos atores locais com relação aos aspectos mencionados. Os resultados evidenciaram que a BHRI, face à singular interação dos aspectos fisiográficos e antrópicos, possui uma diversidade ambiental contrastante, apresentando diferentes potencialidades de uso e níveis de fragilidade. Contudo, o diagnóstico do meio físico, obtido segundo a metodologia apresentada, poderá constituir-se em um instrumento importante para subsidiar a tomada de decisões no que se refere às estratégias de planejamento, manejo adequado, monitoramento e avaliação dos recursos naturais, a serem adotados pelo projeto

Produção de biogás com dejeto de bovino leiteiro em uma propriedade de pequeno porte.

O objetivo do estudo foi avaliar o desempenho de um biodigestor, localizado em uma propriedade produtora de leite de pequeno porte, e estimar o custo evitado com a substituição do gás de cozinha pelo biogás. Foram feitas análises físico‑químicas com amostras coletadas no ponto de entrada (dejeto) e saída (digestato) do biodigestor e foi determinado o teor de metano de dióxido de carbono do biogás. Como principais resultados, obteve‑se, aproximadamente, 20% de remoção de matéria orgânica (SVbs) no ponto de saída e teor de metano no biogás próximo de 60%. Ao estimar a substituição do gás de cozinha pelo biogás consumido, o produtor economizou um botijão de gás por mês e obteve receita de R$ 120,00/mês. Logo, a instalação de biodigestores em pequenas propriedades traz benefícios econômicos e ambientais ao produtor por transformar um passivo ambiental em ativo econômico.Na publicação: Sílvia Gonçalves Belém

Biochemical and genetic characterization of <em>Trypanosoma cruzi N</em>-myristoyltransferase

Co- and post-translational N-myristoylation is known to play a role in the correct subcellular localization of specific proteins in eukaryotes. The enzyme that catalyses this reaction, NMT (N-myristoyltransferase), has been pharmacologically validated as a drug target in the African trypanosome, Trypanosoma brucei. In the present study, we evaluate NMT as a potential drug target in Trypanosoma cruzi, the causative agent of Chagas’ disease, using chemical and genetic approaches. Replacement of both allelic copies of TcNMT (T. cruzi NMT) was only possible in the presence of a constitutively expressed ectopic copy of the gene, indicating that this gene is essential for survival of T. cruzi epimastigotes. The pyrazole sulphonamide NMT inhibitor DDD85646 is 13–23-fold less potent against recombinant TcNMT than TbNMT (T. brucei NMT), with K(i) values of 12.7 and 22.8 nM respectively, by scintillation proximity or coupled assay methods. DDD85646 also inhibits growth of T. cruzi epimastigotes (EC(50)=6.9 μM), but is ~1000-fold less potent than that reported for T. brucei. On-target activity is demonstrated by shifts in cell potency in lines that over- and under-express NMT and by inhibition of intracellular N-myristoylation of several proteins in a dose-dependent manner. Collectively, our findings suggest that N-myristoylation is an essential and druggable target in T. cruzi

Stream diatom biodiversity in islands and continents—A global perspective on effects of area, isolation and environment

Aim The species-area relationship (SAR) is one of the most distinctive biogeographic patterns, but global comparisons of the SARs between island and mainland are lacking for microbial taxa. Here, we explore whether the form of the SAR and the drivers of species richness, including area, environmental heterogeneity, climate and physico-chemistry, differ between islands and similarly sized areas on mainland, referred to as continental area equivalents (CAEs). Location Global. Taxon Stream benthic diatoms. Methods We generated CAEs on six continental datasets and examined the SARs of CAEs and islands (ISAR). Then, we compared CAEs and islands in terms of total richness and richness of different ecological guilds. We tested the factors contributing to richness in islands and CAEs with regressions. We used structural equation models to determine the effects of area versus environmental heterogeneity, climate and local conditions on species richness. Results We found a non-significant ISAR, but a significant positive SAR in CAEs. Richness in islands was related to productivity. Richness in CAEs was mainly dependent on area and climate, but not directly on environmental heterogeneity. Species richness within guilds exhibited inconsistent relationships with island isolation and area. Main conclusions Ecological and evolutionary processes shaping diatom island biogeography do not depend on area at the worldwide scale probably due to the presence of distinct species pool across islands. Conversely, area was an important driver of diatom richness in continents, and this effect could be attributed to dispersal. Continents had greater richness than islands, but this was a consequence of differences in environmental conditions such as specific island climatic conditions. We stress the need for more island data on benthic diatoms, particularly from archipelagos, to better understand the biogeography of this most speciose group of algae

New measurement of neutron capture resonances of 209Bi

The neutron capture cross section of Bi209 has been measured at the CERN n TOF facility by employing the pulse-height-weighting technique. Improvements over previous measurements are mainly because of an optimized detection system, which led to a practically negligible neutron sensitivity. Additional experimental sources of systematic error, such as the electronic threshold in the detectors, summing of gamma-rays, internal electron conversion, and the isomeric state in bismuth, have been taken into account. Gamma-ray absorption effects inside the sample have been corrected by employing a nonpolynomial weighting function. Because Bi209 is the last stable isotope in the reaction path of the stellar s-process, the Maxwellian averaged capture cross section is important for the recycling of the reaction flow by alpha-decays. In the relevant stellar range of thermal energies between kT=5 and 8 keV our new capture rate is about 16% higher than the presently accepted value used for nucleosynthesis calculations. At this low temperature an important part of the heavy Pb-Bi isotopes are supposed to be synthesized by the s-process in the He shells of low mass, thermally pulsing asymptotic giant branch stars. With the improved set of cross sections we obtain an s-process fraction of 19(3)% of the solar bismuth abundance, resulting in an r-process residual of 81(3)%. The present (n,gamma) cross-section measurement is also of relevance for the design of accelerator driven systems based on a liquid metal Pb/Bi spallation target.Comment: 10 pages, 5figures, recently published in Phys. Rev.

Development of best practice recommendations to enhance access to and use of formal community care services for people with dementia in Europe: a Delphi process conducted by the Actifcare project

Objectives Home-dwelling people with dementia and their informal carers experience barriers impeding access to community care services. This study is a part of the Actifcare project where eight countries participated. The aim was to achieve consensus on best practice recommendations for enhancing access to and use of formal community care services. Method A Delphi consensus process was conducted. A total of 48 professional experts, 14 people with dementia and 20 informal carers rated the importance of 72 statements on a 7-point Likert scale. Consensus was based on the median and level of dispersion. Results Sixty-two statements reached consensus, resulting in three categories of recommendations. An appointed contact person was central in Recommendations to enhance access. Coordination and flexibility in setting and type of services were among the Recommendations to enhance use. Training of health care personnel and person-centred care were central Recommendations that can facilitate access or use indirectly. Conclusion The Actifcare Best Practice Recommendations suggest practical measures that can be taken by decision makers to enhance access and use of community care services, and thereby enhance quality of care and quality of life for home dwelling people with dementia and their informal carers

Measurement of the (90,91,92,93,94,96)Zr(n,gamma) and (139)La(n,gamma) cross sections at n_TOF

Open AccessNeutron capture cross sections of Zr and La isotopes have important implications in the field of nuclear astrophysics as well as in the nuclear technology. In particular the Zr isotopes play a key role for the determination of the neutron density in the He burning zone of the Red Giant star, while the (139)La is important to monitor the s-process abundances from Ba up to Ph. Zr is also largely used as structural materials of traditional and advanced nuclear reactors. The nuclear resonance parameters and the cross section of (90,91,92,93,94,96)Zr and (139)La have been measured at the n_TOF facility at CERN. Based on these data the capture resonance strength and the Maxwellian-averaged cross section were calculated