Etanol, meio ambiente e tecnologia: reflexões sobre a experiência brasileira.

O trabalho apresenta uma breve reflexão sobre os principais aspectos ambientais e tecnológicos da experiência brasileira voltada à produção e ao uso de etanol a partir da cana-de-açúcar. Ao se analisar toda a cadeia produtiva do etanol, observa-se que o aproveitamento estratégico de todos os subprodutos da cana-de-açúcar é condição essencial para a sustentabilidade do processo produtivo. Por sua vez, a queima da cana-de-açúcar para colheita e a expansão da monocultura canavieira são fatores que requerem maior atenção. O trabalho demonstra que a produção de etanol de cana-deaçúcar contribui para a sustentabilidade ambiental e que seu uso como combustível renovável é favorável em relação aos combustíveis fósseis

Factors Influencing Farmers Participation in Smallholder Irrigation Schemes: The Case of Ntfonjeni Rural Development Area

Most Swazi households depend on rainfed agriculture for food production, which limits the output because of the unreliable rainfall in the country. To mitigate this, the government has invested in rehabilitation of irrigation schemes to reduce the dependence on rainfall. This study therefore determined the factors influencing participation of farmers in small holder irrigation schemes in Swaziland, using Ntfonjeni Rural Development Area (RDA), as a case study. A multistage sampling technique was used to select 96 farming households, 48 participants of local irrigation scheme and 48 non participants. Data was collected using questionnaires. Analysis involved descriptive statistics and probit model. The study revealed that the participation in small holder irrigation schemes is significantly influenced by households distance to the scheme, age and occupation of household head, farm size and access to credit and membership in other groups. Participation improves output and income for households.  Hence it is recommended that peasant farmers should be assisted with credit facilities as an incentive to participate in irrigation schemes. Key words: Participation, small scale irrigation schemes, Probit, Ntfonjeni, Swaziland

Manejo de sistemas de produção de centeio visando a produção de forragem e de sementes para a agricultura familiar.

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Efeito do extrato alcoólico da folha de erva de bugre no desempenho de sementes de feijão.

O trabalho objetivou avaliar o efeito do extrato alcoólico de folha de Erva de Bugre (Casearia sylvestris) na germinação de sementes de feijão (Phaseolus vulgaris)

Extracts of Tagetes minuta L. front of bacteria regarding bovine mastites.

Bovine mastitis is a problem in the context of animal health. However medicinal plants are a management strategy in agroecological production systems. In this context, the plant Tagetes minuta L. plays a leading role, due to its recognition in the popular pharmacopeia. Thus, the objective of this work was to assess the effect of hydroalcoholic extracts of T. minuta from different collection sites compared to ten bacteria related to bovine mastitis. The antimicrobial evaluation was done through the microdilution technique in syrup, in 96 well microplates in triplicate, for the determination of Minimal Bacterial Concentration (MBC) (%). In the microplates, the extracts of T. minuta and the inoculums of the bacteria were placed in addition to the growth control of the bacteria and the control of the extracts, which were incubated for 72 hours at 37°C in an oven. After this time, aliquots of 5?L of each orifice were transferred to plates containing 5% equine defibrinated blood agar and maintained in incubation for 24 hours at the same previous temperature. With this, the growth readings were performed, with the subsequent interpretation of the results by the geometric mean of the MBC (%). The results indicate that there is a difference in sensitivity to microorganisms by the extracts as a function of the collection sites and both present antimicrobial action

Experimental evidence of solitary wave interaction in Hertzian chains

We study experimentally the interaction between two solitary waves that approach one to another in a linear chain of spheres interacting via the Hertz potential. When these counter propagating waves collide, they cross each other and a phase shift respect to the noninteracting waves is introduced, as a result of the nonlinear interaction potential. This observation is well reproduced by our numerical simulations and it is shown to be independent of viscoelastic dissipation at the beads contact. In addition, when the collision of equal amplitude and synchronized counter propagating waves takes place, we observe that two secondary solitary waves emerge from the interacting region. The amplitude of secondary solitary waves is proportional to the amplitude of incident waves. However, secondary solitary waves are stronger when the collision occurs at the middle contact in chains with even number of beads. Although numerical simulations correctly predict the existence of these waves, experiments show that their respective amplitude are significantly larger than predicted. We attribute this discrepancy to the rolling friction at the beads contacts during solitary wave propagation

Estabilidade da atividade antibacteriana do extrato de Pluchea sagittalis (lam.) cabrera frente a microrganismos causadores da mastite bovina.

O uso das plantas medicinais na prevenção e tratamento da mastite bovina vem apresentando resultados promissores no que tange os sistemas de produção agroecológicos. Nesse contexto, a planta Pluchea sagittalis (Lam.) Cabrera evidencia-se como importante espécie devido aos seus efeitos antimicrobianos. Dessa forma, o objetivo do trabalho foi avaliar extratos da espécie P. sagittalis, elaborados em diferentes anos, frente a 10 microrganismos causadores da mastite bovina. A avaliação antimicrobiana foi por meio da técnica da microdiluição em caldo, em microplacas de 96 orifícios em triplicata, para a determinação da Concentração Bactericida Mínima (%). Nas microplacas, foram colocados os extratos de P. sagittalis e os inóculos das bactérias, além do controle de crescimento das bactérias e dos extratos, que foram incubadas por 72 horas a 37°C em estufa. Após esse período, alíquotas de 5μL de cada orifício foram transferidas para placas contendo meio ágar sangue desfibrinado de equino à 5% e mantidos em incubação por 24 horas, na mesma temperatura anterior. Com isso, foram realizadas as leituras do crescimento para a determinação da CBM (%). Para análise dos dados, utilizou-se o Teste de Kruskal-Wallis, método de Simes-Hochberg, ao nível de 5% de significância. Como resultados, o extrato de P. sagittalis manteve a estabilidade de seus compostos por pelo menos um ano de armazenamento. Os extratos preparados em diferentes anos apresentaram a mesma ação farmacológica e ação bactericida sobre S. aureus, S. intermedius, S. hyicus, S. dysgalactiae, S. uberis e S. agalactiae, nas condições de teste deste trabalho

Efeito do extrato alcoólico de casca de erva de bugre no desempenho de sementes de feijão.

O trabalho teve o objetivo de avaliar a ação de extrato alcoólico de casca de Erva de Bugre (Casearia sylvestris) sobre desenvolvimento de parte aérea e raiz de plântulas de feijão (Phaseolus vulgaris)

Proteomics and Posttranslational Proteomics of Seed Dormancy and Germination

The seed is the dispersal unit of plants and must survive the vagaries of the environment. It is the object of intense genetic and genomic studies because processes related to seed quality affect crop yield and the seed itself provides food for humans and animals. Presently, the general aim of postgenomics analyses is to understand the complex biochemical and molecular processes underlying seed quality, longevity, dormancy, and vigor. Due to advances in functional genomics, the recent past years have seen a tremendous progress in our understanding of several aspects of seed development and germination. Here, we describe the proteomics protocols (from protein extraction to mass spectrometry) that can be used to investigate several aspects of seed physiology, including germination and its hormonal regulation, dormancy release, and seed longevity. These techniques can be applied to the study of both model plants (such as Arabidopsis) and crops

Chromatin interaction analysis reveals changes in small chromosome and telomere clustering between epithelial and breast cancer cells

BACKGROUND: Higher-order chromatin structure is often perturbed in cancer and other pathological states. Although several genetic and epigenetic differences have been charted between normal and breast cancer tissues, changes in higher-order chromatin organization during tumorigenesis have not been fully explored. To probe the differences in higher-order chromatin structure between mammary epithelial and breast cancer cells, we performed Hi-C analysis on MCF-10A mammary epithelial and MCF-7 breast cancer cell lines. RESULTS: Our studies reveal that the small, gene-rich chromosomes chr16 through chr22 in the MCF-7 breast cancer genome display decreased interaction frequency with each other compared to the inter-chromosomal interaction frequency in the MCF-10A epithelial cells. Interestingly, this finding is associated with a higher occurrence of open compartments on chr16-22 in MCF-7 cells. Pathway analysis of the MCF-7 up-regulated genes located in altered compartment regions on chr16-22 reveals pathways related to repression of WNT signaling. There are also differences in intra-chromosomal interactions between the cell lines; telomeric and sub-telomeric regions in the MCF-10A cells display more frequent interactions than are observed in the MCF-7 cells. CONCLUSIONS: We show evidence of an intricate relationship between chromosomal organization and gene expression between epithelial and breast cancer cells. Importantly, this work provides a genome-wide view of higher-order chromatin dynamics and a resource for studying higher-order chromatin interactions in two cell lines commonly used to study the progression of breast cancer