Low-temperature far-infrared ellipsometry of convergent beam

Development of an ellipsometry to the case of a coherent far infrared irradiation, low temperatures and small samples is described, including a decision of the direct and inverse problems of the convergent beam ellipsometry for an arbitrary wavelength, measurement technique and a compensating orientation of cryostat windows. Experimental results are presented: for a gold film and UBe13 single crystal at room temperature (lambda=119 um), temperature dependencies of the complex dielectric function of SrTiO3 (lambda=119, 84 and 28 um) and of YBa2Cu3O7-delta ceramic (lambda=119 um).Comment: 14 pages, 6 figure

Segredos do coração: a escola como espaço para o olhar sensível

Nesse artigo apresentamos a experiência da construção, na escola, de um espaço para o afeto. Em tal espaço, através da atividade artística, torna-se possível trabalhar perdas, cultivar segredos, sonhos e desejos. Espaço-lugar que permite a construção de um olhar sensível para as histórias de cada um e para a memória coletiva. A dinâmica envolvida na proposta expressa uma dimensão do ensino de arte na atualidade, como espaço de atuação entre a objetividade e a subjetividade no trabalho com os alunos. Nesta sintonia, durante as aulas de arte que configuraram a experiência aqui analisada, alinhávamos histórias dos participantes com os fios da experiência estética, cruzando referências das culturas africana e indígena com a tradição das bordadeiras, que tecem a sua história de vida com fios e panos. Na composição de todos esses elementos, criamos na escola um lugar de acolhimento das individualidades, das subjetividades de cada um de nós, verdadeiros tesouros segredados

Genome structure of a Saccharomyces cerevisiae strain widely used in bioethanol production

Bioethanol is a biofuel produced mainly from the fermentation of carbohydrates derived from agricultural feedstocks by the yeast Saccharomyces cerevisiae. One of the most widely adopted strains is PE-2, a heterothallic diploid naturally adapted to the sugar cane fermentation process used in Brazil. Here we report the molecular genetic analysis of a PE-2 derived diploid (JAY270), and the complete genome sequence of a haploid derivative (JAY291). The JAY270 genome is highly heterozygous (∼2 SNPs/kb) and has several structural polymorphisms between homologous chromosomes. These chromosomal rearrangements are confined to the peripheral regions of the chromosomes, with breakpoints within repetitive DNA sequences. Despite its complex karyotype, this diploid, when sporulated, had a high frequency of viable spores. Hybrid diploids formed by outcrossing with the laboratory strain S288c also displayed good spore viability. Thus, the rearrangements that exist near the ends of chromosomes do not impair meiosis, as they do not span regions that contain essential genes. This observation is consistent with a model in which the peripheral regions of chromosomes represent plastic domains of the genome that are free to recombine ectopically and experiment with alternative structures. We also explored features of the JAY270 and JAY291 genomes that help explain their high adaptation to industrial environments, exhibiting desirable phenotypes such as high ethanol and cell mass production and high temperature and oxidative stress tolerance. The genomic manipulation of such strains could enable the creation of a new generation of industrial organisms, ideally suited for use as delivery vehicles for future bioenergy technologies

Description of novel microsatellite loci in the Neotropical fish Prochilodus argenteus and cross-amplification in P. costatus and P. lineatus

Prochilodus is one of the most important fish resources of South America, in addition to the important role it plays in nutrient cycling of Neotropical rivers. In the present study, we describe the isolation and characterization of nine novel microsatellite loci in Prochilodus argenteus. The number of alleles per polymorphic locus varied from 5 (Par76) to 21 (Par85), revealing a total of 116 alleles. The values of observed and expected heterozygosities ranged from 0.629 (Par69) to 0.926 (Par85 and Par86) and from 0.643 (Par66) to 0.931 (Par80), respectively. Furthermore, the ability of these and other previously described microsatellite markers to amplify orthologous loci was tested in two related species, Prochilodus costatus and Prochilodus lineatus. These loci will be useful for studies of population genetic structure in this group of fishes, and in aiding future genetic mapping studies of P. argenteus