14,799 research outputs found
O programa nacional de fortalecimento da agricultura familiar no Brasil: uma análise sobre a distribuição regional e setorial dos recursos.
No Brasil, as políticas públicas para o espaço rural sempre tenderam a priorizar a agricultura patronal, em detrimento dos agricultores familiares. Todavia, os estudos realizados pelos órgãos FAO - INCRA deram subsídio para a criação do Programa Nacional de Fortalecimento da Agricultura Familiar (PRONAF), resultando em um novo direcionamento dos investimentos públicos, os quais passaram a contemplar o segmento dos agricultores familiares. Entende-se o PRONAF como uma política não-compensatória, que, apesar de seus problemas, tem contribuído de fato para mudanças e melhorias no espaço agrário brasileiro. Desde sua criação no final da década de 1990, o PRONAF passou por várias mudanças em sua estrutura administrativa e operacional, a fim de alcançar seus objetivos e adequar-se face a complexa realidade social agrária brasileira. Sendo assim, o presente estudo visa discutir as ações do Estado por meio desse Programa, a partir de suas linhas de atuação, bem como analisar a distribuição de suas concessões de crédito regional e setorialmente. Assim, os procedimentos metodológicos utilizados para a realização deste trabalho compreendem pesquisa bibliográfica e documental, além de pesquisa em fontes secundárias, no intuito de obter dados e informações relevantes para a análise das relações sociais estabelecidas em meio a esse processo de concretização e espacialização desse Programa. Dentre as implicações do PRONAF pode-se notar em âmbito nacional, uma diminuição da disparidade regional brasileira, bem como a preocupação que o Programa tem demonstrado com os aspectos socioculturais locais e regionais, como forma de garantir que seus investimentos perpassem a dimensão econômica, mas valorize outras dimensões, a exemplo dos elementos culturais
Genetic control of purothionins in wheat: problems of the aneuploid analysis when searching for regulatory genes
The study of the genetic control of purothionins in wheat endosperm illustrates some of the problems and pitfalls faced in aneuploid analysis of regulatory effects. Biochemical and genetic evidence is presented indicating that the possible regulatory effect of genes located in group 5 chromosomes on the expression of the purothionin structural genes located in group 1 chromosomes is not actually operating "in vivo"
Expression of homoeologous molecular systems in wheat alloploids
Allopolyploidy is widespread in the plant kingdom, where it has been of considerable evolutionary significance. Although the existence of heterotic interactions between the genomes that make up an alloploid have been generally assumed, the precise nature of these interactions has not been extensively investigated. Presently available evidence about metabolic integration of the wheat genomes is examined in search of new insights about the different modes of genome interaction. Although additive expression seems to be the case for many homoeologous systems, more complex patterns of integration have become evident. Examples of enzyme subunit complementation, gene compensation and other dosage effects, holoprotein completion, and complementation of metabolic pathways are discussed
Multidisciplinary teaching of Biotechnology and Omics sciences
In the last years, there was a great boom in the Omics fields that have developed as multidisciplinary
sciences. They use laboratory techniques related to Biology and Chemistry but also Bioinformatics
tools. However, the developmental progress of these disciplines has led that much of undergraduate
studies related to Biology have curricula that become outdated. From this point of view, it is
necessary to focus the students to the fundamentals and techniques of complementary disciplines that
will be essentials for the understanding of the Omics sciences. In the present work, we have
developed a new teaching approach for Biochemistry, Biology and Bioinformatics students. They
formed interdisciplinary working groups. These groups have prepared and presented
communications about different techniques or methods in Molecular Biology, Omics or
Bioinformatics participating in a technical meeting. This learning strategy “I do and I learn” has
enabled to the students a first contact with the scientific communication including the approach to the
scientific literature to acquire technical knowledge. The cooperation between students from different
disciplines has enriched their point of view and even has been used in some practical master’s works.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Ion condensation on charged patterned surfaces
We study ion condensation onto a patterned surface of alternating charges.
The competition between self-energy and ion-surface interactions leads to the
formation of ionic crystalline structures at low temperatures. We consider
different arrangements of underlying ionic crystals, including single ion
adsorption, as well as the formation of dipoles at the interface between
charged domains. Molecular dynamic simulation illustrates existence of single
and mixed phases. Our results contribute to understanding pattern recognition,
and molecular separation and synthesis near patterned surfaces.Comment: 3 figure
Charged Particles on Surfaces: Coexistence of Dilute Phases and Periodic Structures on Membranes
We consider a mixture of one neutral and two oppositely charged types of
molecules confined to a surface. Using analytical techniques and molecular
dynamics simulations, we construct the phase diagram of the system and exhibit
the coexistence between a patterned solid phase and a charge-dilute phase. The
patterns in the solid phase arise from competition between short-range
immiscibility and long-range electrostatic attractions between the charged
species. The coexistence between phases leads to observations of stable
patterned domains immersed in a neutral matrix background.Comment: 5 pages, 3 figure
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