Biological remodelling: Stationary energy, configurational change, internal variables and dissipation

Remodelling is defined as an evolution of microstructure or variations in the configuration of the underlying manifold. The manner in which a biological tissue and its subsystems remodel their structure is treated in a continuum mechanical setting. While some examples of remodelling are conveniently modelled as evolution of the reference configuration (Case I), others are more suited to an internal variable description (Case II). In this paper we explore the applicability of stationary energy states to remodelled systems. A variational treatment is introduced by assuming that stationary energy states are attained by changes in microstructure via one of the two mechanisms--Cases I and II. An example is presented to illustrate each case. The example illustrating Case II is further studied in the context of the thermodynamic dissipation inequality.Comment: 24 pages, 4 figures. Replaced version has corrections to typos in equations, and the corresponding correct plot of the solution--all in Section

Avaliação econômica de pastagens: método da taxa interna de retorno com uso de microcomputador.

As baixas qualidade e disponibilidade das pastagens, especialmente na estação seca, têm sido apontadas como as principais causas do baixo desfrute do rebanho brasileiro. Na tentativa de encontrar soluções para este problema, pesquisadores, extensionistas e produtores têm intensificado esforços na busca de gramíneas exóticas, bem como estratégias alternativas para formação e conservação de pastagem cultivada, para oferecer melhor alimentação para os rebanhos a custos mais baixos. Entretanto, um aspecto que deve ser levado em conta na busca da pastagem mais adequada é a multiplicidade de condições em cada fazenda. Diferentes categorias animais e condições de clima, solo, vegetação nativa e infraestrutura regional, determinam as espécies forrageiras e os sistemas de formação e conservação de pastagem mais adequados economicamente. Dentre os métodos de formação e conservação de pastagens, há um grande número de alternativas. O método de abertura da mata, mecânico ou manual, o aproveitamento Inicial da área, com lavoura ou capim. a intensidade de uso e conservação da pastagem. a freqüência de rocadas e adubação constituem decisões determinantes de custos e benefício das pastagens.bitstream/item/131376/1/avaliacao-economica-de-pastagens.pd

Sensory stability and aromatic differentiation of tropical Brazilian wines.

Our objective was determined stability of sensory parameters and aromatic differentiation of tropical wines from Northeast of Brazil by Quantitative Descriptive Analysis (QDA

Sensory stability and aromatic differentiation of tropical Brazilian wines.

Our objective was determined stability of sensory parameters and aromatic differentiation of tropical wines from Northeast of Brazil by Quantitative Descriptive Analysis (QDA

The Role of Carcinine in Signaling at the Drosophila Photoreceptor Synapse

The Drosophila melanogaster photoreceptor cell has long served as a model system for researchers focusing on how animal sensory neurons receive information from their surroundings and translate this information into chemical and electrical messages. Electroretinograph (ERG) analysis of Drosophila mutants has helped to elucidate some of the genes involved in the visual transduction pathway downstream of the photoreceptor cell, and it is now clear that photoreceptor cell signaling is dependent upon the proper release and recycling of the neurotransmitter histamine. While the neurotransmitter transporters responsible for clearing histamine, and its metabolite carcinine, from the synaptic cleft have remained unknown, a strong candidate for a transporter of either substrate is the uncharacterized inebriated protein. The inebriated gene (ine) encodes a putative neurotransmitter transporter that has been localized to photoreceptor cells in Drosophila and mutations in ine result in an abnormal ERG phenotype in Drosophila. Loss-of-function mutations in ebony, a gene required for the synthesis of carcinine in Drosophila, suppress components of the mutant ine ERG phenotype, while loss-of-function mutations in tan, a gene necessary for the hydrolysis of carcinine in Drosophila, have no effect on the ERG phenotype in ine mutants. We also show that by feeding wild-type flies carcinine, we can duplicate components of mutant ine ERGs. Finally, we demonstrate that treatment with H3 receptor agonists or inverse agonists rescue several components of the mutant ine ERG phenotype. Here, we provide pharmacological and genetic epistatic evidence that ine encodes a carcinine neurotransmitter transporter. We also speculate that the oscillations observed in mutant ine ERG traces are the result of the aberrant activity of a putative H3 receptor

Fano resonances in plasmonic core-shell particles and the Purcell effect

Despite a long history, light scattering by particles with size comparable with the light wavelength still unveils surprising optical phenomena, and many of them are related to the Fano effect. Originally described in the context of atomic physics, the Fano resonance in light scattering arises from the interference between a narrow subradiant mode and a spectrally broad radiation line. Here, we present an overview of Fano resonances in coated spherical scatterers within the framework of the Lorenz-Mie theory. We briefly introduce the concept of conventional and unconventional Fano resonances in light scattering. These resonances are associated with the interference between electromagnetic modes excited in the particle with different or the same multipole moment, respectively. In addition, we investigate the modification of the spontaneous-emission rate of an optical emitter at the presence of a plasmonic nanoshell. This modification of decay rate due to electromagnetic environment is referred to as the Purcell effect. We analytically show that the Purcell factor related to a dipole emitter oriented orthogonal or tangential to the spherical surface can exhibit Fano or Lorentzian line shapes in the near field, respectively.Comment: 28 pages, 10 figures; invited book chapter to appear in "Fano Resonances in Optics and Microwaves: Physics and Application", Springer Series in Optical Sciences (2018), edited by E. O. Kamenetskii, A. Sadreev, and A. Miroshnichenk

Época de aplicação e tipos de dessecantes na qualidade fisiológica de sementes de soja.

Objetivou-se neste trabalho avaliar o efeito de dessecantes aplicados em diferentes épocas, na qualidade fisiológica e no vigor de sementes de soja da cultivar BRS 247 RR

Estimativa do custo de producao da carne bovina para a regiao Centro-oeste: setembro de 1986.

bitstream/item/138579/1/COT-30.pdfCNPGC

Carbon dynamics in aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

International audienceThis is the first estimation on carbon dynamics in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in Central Southern America. In four 1-ha plots in stands characterized by the pioneer species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ?10 cm diameter at breast height, DBH) have been performed and converted to predictions of AGWB by five different allometric models using two or three predicting parameters (DBH, tree height, wood density). Best prediction has been achieved using allometric equations with three independent variables. Carbon stocks (50% of AGWB) vary from 7.4 to 100.9 Mg C ha?1 between the four stands. Carbon sequestration differs 0.50?4.24 Mg C ha?1 yr?1 estimated by two growth models derived from tree-ring analysis describing the relationships between age and DBH for V. divergens and other tree species. We find a close correlation between estimated tree age and C-stock, C-sequestration and C-turnover (mean residence of C in AGWB)