Biological Physics
Mostrando 13-24 de 42 artigos, teses e dissertações.
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13. DEVELOPING A VERSATILE MONOCHROMATIZATION SYSTEM FOR X-RAYS / DESENVOLVIMENTO DE UM SISTEMA DE MONOCROMATIZAÇÃO VERSÁTIL PARA RAIOS-X
The investigation of the dynamics of the interaction of high-energy X-rays and molecules of biological interest requires the energy of the X-rays to be well defined, so that one can establish the dependence of the molecular ionization and fragmentation patterns as functions of the incident beam energy. For this purpose, a versatile system for the monochromat
Publicado em: 2009
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14. Assessment of the Cambisol structure sustainability under different land uses systems in Western Amazon. / AvaliaÃÃo da sustentabilidade da estrutura de um Cambissolo sob diferentes sistemas de uso da terra na AmazÃnia Ocidental.
The adequate use of the soil is important for the preservation of the natural resources and for a search of a sustainable agriculture. However, itâs inadequate use promotes degradation of the soil altering its physical, chemical and biological properties. In order for the soil management happens in a sustainable way it is important to diagnose through effic
Publicado em: 2009
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15. A numerical study about the determination of parameters in an incompressible and linearly elastic solid / Estudo numérico sobre a determinação de parâmetros em um sólido elástico-linear e incompressível
The theory of classical linear elasticity is used to model of problems in medical physics that are related to the determination of elastic parameters of biological tissues from the measurement in vivo, or, in vitro of either displacements or strains. Based on experimental observations, which indicate that the abnormal biological tissues have different mechan
Publicado em: 2008
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16. Propriedades eletrônicas de nanofios semicondutores / Electronic properties of semiconductor nanowires
We have performed an extensive study on the electronic and structural properties of silicon nanowires (NWs) using parameter free computational simulations (DFT). We show that in Si NWs, surfaces whose atoms are connected to inner ones perpendicularly to the wires axes become electronically inactive at the band edges. However, when these bonds are oriented al
Publicado em: 2008
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17. SOIL PHYSICAL AND BIOLOGICAL CHARACTERIZATION AFTER HERBICIDES APPLICATION IN BLACK WATTLE (Acacia mearnsii De Wild.) STANDS IN RIO GRANDE DO SUL / CARACTERIZAÇÃO FÍSICA E BIOLÓGICA DO SOLO APÓS APLICAÇÃO DE HERBICIDAS EM PLANTIOS DE ACÁCIA-NEGRA (Acacia mearnsii De Wild.) NO RIO GRANDE DO SUL
The study of soil quality biological indicators in areas classified as forest production units is important to understand the ecological processes that occur in these systems. Monitoring the soil fauna in modified environments, when management practices involve chemical products in the environment, is an instrument that allows to evaluate not only the soil q
Publicado em: 2008
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18. Hirsch's index: a case study conducted at the Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo
An analysis of scientific bibliographic productivity using the Hirsch h-index, information from the Institute of Scientific Information database and the Curriculum Lattes (CNPq, Brazil) was performed at the Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (FFCLRP-USP) that has four departments in natural, biological a
Brazilian Journal of Medical and Biological Research. Publicado em: 2007-11
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19. Structural and dynamical properties of a quasi-onedimensional classical binary system / Estudo das propriedades estruturais e dinÃmicas de um sistema binÃrio quasi-unidimensional.
The aim of this work is to study the structural and dynamical properties of a classical binary system of charged particles confined in a two dimensional channel. Such a system is described in the literature as quasi-unidimensional, and its relevance is supported by the possibility of technological applications, shown recently in the scientific literature, an
Publicado em: 2007
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20. Um sistema presa-predador com evasão mediada por feromônio de alarme / A predator-prey model with pursuit and evasion triggered by alarm pheromones
Pattern, structure and emergent collective properties are ubiquitous in systems with many units (alive or inanimated) coupled through nonlinear interactions. Within this context, the study of cooperative phenomena in population dynamics of ecological interest has attracted the attention of the mathematicians and physicists since Lotka and Volterra in the 192
Publicado em: 2006
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21. Cooperação e Conflito em Modelos de Vesículas Pré-Bióticas / Cooperation and Conflict in Prebiotic Vesicle Models
The primordial genetic information crisis as defined by the Eigens quasispecies model, which can be used as a paradigm here, has been a challenge to any theory about the origin of life and prebiotic evolution for more than three decades. Despite several tentative solutions proposed along this period, theres no consensual solution to the scientific commun
Publicado em: 2006
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22. Implementação de um protocolo Dynamic Clamp em sistema Linux em tempo real para a produção de condutâncias em neurônios biológicos e eletrônicos / Implementation of a protocol dynamic clamp in system Linux in real time for the production of artifical conductances in biological and electronic neurons
O protocolo conhecido como Dynamic Clamp consiste em utilizar um computador para introduzir condutâncias artificiais em um neurônio biológico. O modo como estas condutâncias dependem da voltagem da membrana ou do tempo são modelado por equações diferenciais que são integradas em tempo real por um computador conectado ao neurônio biológico. Resumida
Publicado em: 2006
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23. Influence of vegetation cover on nutrient cycling in soil solution at the area of Manaus AM. / Influência da cobertura vegetal na ciclagem de nutrientes via solução do solo na região de Manaus - AM.
The main objective of this study was to contribute for the sustainability of land use in the central Amazon, evaluating the influence of vegetation cover on nutrient concentrations in soil solution that is, on the amounts of cations, anions and dissolved organic carbon (DOC). Using a primary forest as reference, we compared these concentrations with those in
Publicado em: 2005
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24. Evolutionary aging models: reproductive regimes and the Y chromosome degeneration. / Modelos evolucionários de envelhecimento: regimes reprodutivos e a degeneração do cromossomo Y.
Aging theories can be classified in two types: biochemical theory and evolutionary theory. The biochemical theories explain ageing due to imperfections on the biochemical process responsible for the maintenance of life. The evolutionary theories explain aging without any biochemical mechanisms. They support only adaptive strategies, such as reproduction, her
Publicado em: 2003