Avaliação de linhagens de arroz irrigado com tipo de grãos para a culinária japonsesa.

O objetivo deste trabalho foi avaliar as características agronômicas e culinárias de nove linhagens de arroz irrigado nas condições de cultivo do Rio Grande do Sul. Foram conduzidos sete ensaios de Valor de Cultivo e Uso (VCU) nos Municípios de Alegrete e Uruguaiana nos anos agrícolas 2001/02 a 2003/04, constituídos de nove linhagens mais a testemunha BRS Bojuru. O delineamento experimental usado foi o de blocos ao acaso com quatro repetições. Das linhagens avaliadas, a CNAi 9903 destacou-se por apresentar boas características agronômicas e qualidade de grãos favoráveis à culinária japonesa.bitstream/CNPAF/23533/1/bolpesq_17.pd

Linhagens de arroz irrigado com potencial para indicação como novas cultivares para a região tropical do Brasil.

O objetivo do presente trabalho foi analisar o desempenho das linhagens avaliadas nos Ensaios Regionais conduzidos na Região Tropical, no ano agrícola 2003/04. Esta região tem como principais problemas, doenças com ênfase para brusone, cuja ocorrência é favorecida pelas condições climáticas predominantes na região e pelo manejo deficiente da cultura; baixo nível de tecnologia utilizado; e cultivares com grãos de má qualidade, ocasionando perda de competitividade do produto no mercado.bitstream/CNPAF/23008/1/comt_88.pd

Correlation of interfacial bonding mechanism and equilibrium conductance of molecular junctions

We report theoretical investigations on the role of interfacial bonding mechanism and its resulting structures to quantum transport in molecular wires. Two bonding mechanisms for the Au-S bond in an Au(111)/1,4-benzenedithiol(BDT)/Au(111) junction were identified by ab initio calculation, confirmed by a recent experiment, which, we showed, critically control charge conduction. It was found, for Au/ BDT/Au junctions, the hydrogen atom, bound by a dative bond to the Sulfur, is energetically non-dissociative after the interface formation. The calculated conductance and junction breakdown forces of H-non-dissociative Au/BDT/Au devices are consistent with the experimental values, while the H-dissociated devices, with the interface governed by typical covalent bonding, give conductance more than an order of magnitude larger. By examining the scattering states that traverse the junctions, we have revealed that mechanical and electric properties of a junction have strong correlation with the bonding configuration. This work clearly demonstrates that the interfacial details, rather than previously believed many-body effects, is of vital importance for correctly predicting equilibrium conductance of molecular junctions; and manifests that the interfacial contact must be carefully understood for investigating quantum transport properties of molecular nanoelectronics.Comment: 18 pages, 6 figures, 2 tables, to be appeared in Frontiers of Physics 9(6), 780 (2014

Rapid Saline Permafrost Thaw Below a Shallow Thermokarst Lake in Arctic Alaska

Permafrost warming and degradation is well documented across the Arctic. However, observation- and model-based studies typically consider thaw to occur at 0°C, neglecting the widespread occurrence of saline permafrost in coastal plain regions. In this study, we document rapid saline permafrost thaw below a shallow arctic lake. Over the 15-year period, the lakebed subsided by 0.6 m as ice-rich, saline permafrost thawed. Repeat transient electromagnetic measurements show that near-surface bulk sediment electrical conductivity increased by 198% between 2016 and 2022. Analysis of wintertime Synthetic Aperture Radar satellite imagery indicates a transition from a bedfast to a floating ice lake with brackish water due to saline permafrost thaw. The regime shift likely contributed to the 65% increase in thermokarst lake lateral expansion rates. Our results indicate that thawing saline permafrost may be contributing to an increase in landscape change rates in the Arctic faster than anticipated

Magneto-Conductance Anisotropy and Interference Effects in Variable Range Hopping

We investigate the magneto-conductance (MC) anisotropy in the variable range hopping regime, caused by quantum interference effects in three dimensions. When no spin-orbit scattering is included, there is an increase in the localization length (as in two dimensions), producing a large positive MC. By contrast, with spin-orbit scattering present, there is no change in the localization length, and only a small increase in the overall tunneling amplitude. The numerical data for small magnetic fields $B$, and hopping lengths $t$, can be collapsed by using scaling variables $B_\perp t^{3/2}$, and $B_\parallel t$ in the perpendicular and parallel field orientations respectively. This is in agreement with the flux through a `cigar'--shaped region with a diffusive transverse dimension proportional to $\sqrt{t}$. If a single hop dominates the conductivity of the sample, this leads to a characteristic orientational `finger print' for the MC anisotropy. However, we estimate that many hops contribute to conductivity of typical samples, and thus averaging over critical hop orientations renders the bulk sample isotropic, as seen experimentally. Anisotropy appears for thin films, when the length of the hop is comparable to the thickness. The hops are then restricted to align with the sample plane, leading to different MC behaviors parallel and perpendicular to it, even after averaging over many hops. We predict the variations of such anisotropy with both the hop size and the magnetic field strength. An orientational bias produced by strong electric fields will also lead to MC anisotropy.Comment: 24 pages, RevTex, 9 postscript figures uuencoded Submitted to PR

Futuros do Trabalho nas Ciências Sociais: Relatório de Pesquisa

This report presents the results of the research "Futures of work in the social sciences.” This study was based on a survey and in-depth interviews with the academic community. Two main points were investigated: perceptions of the profession and work routines. It also addressed questions on generational, gender, and racial inequalities in the area. The results provide a broad overview of academic work in the Social Sciences in Brazil.Este relatório apresenta resultados da pesquisa "Futuros do trabalho nas ciências sociais". O estudo se baseou em um survey e na realização de entrevistas em profundidade com a comunidade acadêmica e teve como objetivos investigar as percepções acerca dos usos do tempo e das rotinas de trabalho acadêmico na área; conhecer percepções e expectativas de múltiplas gerações de cientistas sociais sobre a profissão; investigar desigualdades de geração, gênero e raça que atravessam a prática profissional na academia. Os resultados proporcionam um retrato abrangente de distintas gerações que integram a comunidade de trabalho acadêmico na área

Arroz preto: nova opção culinária para o Brasil.

A Embrapa Arroz e Feijão desenvolveu algumas linhagens de arroz preto com grão similar ao tipo agulhinha e realizou alguns estudos agronômicos e de qualidade de grãos com o objetivo de estimular a ampliação de novos mercados para os produtores atingirem um nicho específico, com potencial no consumo interno e externo, já que o arroz preto tem amplo mercado na Europa e nos Estados Unidos. Apesar de ainda incipiente no Brasil, é grande o potencial de mercado em qualquer região brasileira com vantagens nutricionais, funcionais e culinárias agregadas. O arroz preto deve ser considerado um produto especial e ser analisado como tal, não sendo o intuito do trabalho recomendar um tipo de arroz colorido para substituir o arroz branco ou integral na dieta brasileira, mas sim, sugerir alternativas de diversificação culinária e de geração de renda.bitstream/CNPAF-2009-09/27598/1/comt_147.pd

Genetic history of Hepatitis C virus in Venezuela: high diversity and long time of evolution of HCV genotype 2

Background: The subtype diversity of the hepatitis C virus (HCV) genotypes is unknown in Venezuela. Methodology/Principal Findings: Partial sequencing of the NS5B region was performed in 310 isolates circulating in patients from 1995 to 2007. In the samples collected between 2005 and 2007, HCV genotype 1 (G1) was the most common genotype (63%), composed as expected of mainly G1a and G1b. G2 was the second most common genotype (33%), being G2a almost absent and G2j the most frequent subtype. Sequence analysis of the core region confirmed the subtype assignment performed within the NS5b region in 63 isolates. The complete genome sequence of G2j was obtained. G2j has been described in France, Canada and Burkina Fasso, but it was not found in Martinique, where several subtypes of G2 circulate in the general population. Bayesian coalescence analysis indicated a most recent common ancestor (MRCA) of G2j around 1785, before the introduction of G1b (1869) and G1a (1922). While HCV G1a and G1b experienced a growth reduction since 1990, coincident with the time when blood testing was implemented in Venezuela, HCV G2j did not seem to reach growth equilibrium during this period. Conclusions/Significance: Assuming the introduction of G2j from Africa during the slave trade, the high frequency of G2j found in Venezuela could suggest: 1- the introduction of African ethnic groups different from the ones introduced to Martinique or 2- the occurrence of a founder effect. This study represents an in-depth analysis of the subtype diversity of HCV in Venezuela, which is still unexplored in the Americas and deserves further studies.Fil: Sulbarán, Maria Z.. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Di Lello, Federico Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Virología; ArgentinaFil: Sulbarán, Yoneira. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Cosson, Clarisa. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Loureiro, Carmen. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Rangel, Héctor R.. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Cantaloube, Jean F.. Etablissement Français du Sang Alpes-Méditerranée. Unité Emergence et Co-évolution virale; FranciaFil: Campos, Rodolfo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Virología; ArgentinaFil: Moratorio, Gonzalo. Universidad de la Republica; Uruguay. Instituto Pasteur de Montevideo; UruguayFil: Cristina, Juan. Universidad de la Republica; UruguayFil: Pujol, Flor H.. Instituto Venezolano de Investigaciones Cientificas; Venezuel