MATHEMATICAL MODEL AND EXPERIMENTAL PROCEEDINGS TO DETERMINE ROLL WAVES IN OPEN CHANNELS

The goal of this paper is consolidate a representative model previously developed by RMVP team (Rheological Studies on Viscous and Viscousplastic Materials) from UNESP - Ilha Solteira, for a typical phenomenonthat occurs on spillways, river's bed, landslides, mudflows, blood flows, for Newtonian and non-Newtonian fluids, known as roll waves. Another goal of this paper is present an experimental project designed for capturing measurements (amplitude and wavelength) of these instabilities. From a mathematical perspective, a first-order analytical model is showed, based on Cauchy's equations system, once developed by the team (Ferreira, 2007), which provides a generation condition for roll waves through temporal linear stability analysis. This model follows the remarkable work of Dressler (1949) and it is able to generate roll waves for many rheological configurations, from Newtonian to Herschel & Bulkley models, representing clean water up to muddy mixtures, respectively. A numerical routine developed in Matlab/Simulink is used to show some results that illustrate roll waves pattern. Due to the lack of roll waves data (amplitude and wavelength), the team started to focus on the experimental approach of the phenomenon, aiming to design an apparatus that would be capable to reproduce roll waves in special conditions of flow, isolated from external perturbations. This project is here presented along with a proposal of a photometric system to ascertain measures of the flow height through light absorption technique, based on experiments found in the literature. The final execution of this experiment and the correct obtaining of amplitude and wavelength will contribute for the validation of the model here presented

Carrier relaxation in GaAs v-groove quantum wires and the effects of localization

Carrier relaxation processes have been investigated in GaAs/AlGaAs v-groove quantum wires (QWRs) with a large subband separation (46 meV). Signatures of inhibited carrier relaxation mechanisms are seen in temperature-dependent photoluminescence (PL) and photoluminescence-excitation (PLE) measurements; we observe strong emission from the first excited state of the QWR below ~50 K. This is attributed to reduced inter-subband relaxation via phonon scattering between localized states. Theoretical calculations and experimental results indicate that the pinch-off regions, which provide additional two-dimensional confinement for the QWR structure, have a blocking effect on relaxation mechanisms for certain structures within the v-groove. Time-resolved PL measurements show that efficient carrier relaxation from excited QWR states into the ground state, occurs only at temperatures > 30 K. Values for the low temperature radiative lifetimes of the ground- and first excited-state excitons have been obtained (340 ps and 160 ps respectively), and their corresponding localization lengths along the wire estimated.Comment: 9 pages, 8 figures, submitted to Phys. Rev. B Attempted to correct corrupt figure

Produção e conservação de forragens em escala para sustentabilidade dos rebanhos caprinos e ovinos na agricultura de base familiar.

Esta revisão pretende abordar alguns aspectos sobre a produção e conservação de forragens em escala para sustentabilidade dos rebanhos caprinos e ovinos na agricultura de base familiar

Comparison of growth and lipid accumulation at three different growth regimes with Desmodesmus sp.

The production of third generation biofuel and use of microalgae as feedstock have recently gained increased attention in the research area in search of more sustainable processes. These microorganisms have characteristics that offer great potential to produce either feedstock to other process or even final use products. They have fast growth rates and accumulation of intracellular metabolites, including lipids. There are three basic types of cultures in which microalgae can develop: autotrophic, heterotrophic and mixotrophic. The objective of this work was to study the growth of the microalgae Desmodesmus sp. in these three types of cultivations in order to establish the most effective farming strain for lipids production. It was observed that the strain had higher yields of biomass and lipids in the mixotrophic cultivation with glucose (10 g L−1) as the carbon source, obtaining 54.5 × 106 cells mL−1 with a growth rate of 0.28 (days−1) and 25.1% of lipids in a 6 day cultivation time9421427COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação2014/10064-9; 2015/19935-

Mutations Of Androgen Receptor Gene In Brazilian Patients With Male Pseudohermaphroditism.

We describe the identification of point mutations in the androgen receptor gene in five Brazilian patients with female assignment and behavior. The eight exons of the gene were amplified by the polymerase chain reaction (PCR) and analyzed for single-strand conformation polymorphism (SSCP) to detect the mutations. Direct sequencing of the mutant PCR products demonstrated single transitions in three of these cases: G-->A in case 1, within exon C, changing codon 615 from Arg to His; G-->A in case 2, within exon E, changing codon 752 from Arg to Gln, and C-->T in case 3, within exon B, but without amino acid change.31775-

Longitudinal photocurrent spectroscopy of a single GaAs/AlGaAs v-groove quantum wire

Modulation-doped GaAs v-groove quantum wires (QWRs) have been fabricated with novel electrical contacts made to two-dimensional electron-gas (2DEG) reservoirs. Here, we present longitudinal photocurrent (photoconductivity/PC) spectroscopy measurements of a single QWR. We clearly observe conductance in the ground-state one-dimensional subbands; in addition, a highly temperature-dependent response is seen from other structures within the v-groove. The latter phenomenon is attributed to the effects of structural topography and localization on carrier relaxation. The results of power-dependent PC measurements suggest that the QWR behaves as a series of weakly interacting localized states, at low temperatures

Detecção, transmissão e patogenicidade de fungos em sementes de angico-vermelho (Parapiptadenia rigida).

Angico-vermelho (Parapiptadenia rigida (Benth.) Brenan) é uma espécie nativa de grande valor ecológico e econômico, importante para a recomposição de áreas degradadas. O presente trabalho avaliou incidência, transmissão e patogenicidade de fungos associados a sementes de angico-vermelho de distintas procedências do Estado do Rio Grande do Sul. Para isso, utilizaram-se três amostras de sementes, com as quais realizaram-se testes de germinação, sanidade empregandose o método do papel-filtro (PF) e de plaqueamento em batata-dextrose-ágar (BDA), transmissão e patogenicidade dos fungos. A germinação das sementes de angico-vermelho variou de 63 a 91 %. Os fungos considerados potencialmente patogênicos encontrados associados as sementes de angico-vermelho foram: Alternaria sp.; Botrytis sp.; Fusarium sp.; Cladosporium sp. e Pestalotia sp.; sendo que Fusarium sp. foi detectado em todas as amostras pelo método PF, e foi transmitido via semente causando má formação do sistema radicular e dos cotilédones e tombamento de pré emergência. Sua patogenicidade foi confirmada

Produtividade de Cultivares de Palma de Óleo na Fase Juvenil em Área de Floresta Alterada no Sul de Roraima.

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