Genes do eixo somatotrófico e características de crescimento numa população F2 de bovinos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade sanitária e germinação de sementes de pinhão-manso

O pinhão-manso é uma espécie arbustiva que está se destacando pelo interesse para produção de biocombustível, porém, os estudos sobre controle de qualidade das sementes estão se iniciando. Neste trabalho objetivou-se estudar o efeito da temperatura e do tempo de contagem na germinação de sementes de pinhão-manso, conduzido em papel toalha bem como avaliar a qualidade sanitária das sementes, desinfestadas ou não com hipoclorito de sódio, a 2%. O estudo foi conduzido, com sementes de pinhão-manso extraídas de frutos maduros, coletados na planta. O teste de germinação foi conduzido nas temperaturas de 25 ºC e alternadas de 20-30 ºC, com contagens aos 6, 9 e 12 dias. O teste de sanidade foi conduzido a 20 ºC com fotoperíodo de 12 h por 7 dias. Foi utilizado o delineamento experimental inteiramente casualizado com quatro repetições e empregado o teste F na análise de variância dos dados de germinação e do índice de velocidade de germinação. As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. O potencial máximo de germinação das sementes de pinhão-manso foi obtido na temperatura de 25 ºC, com contagens aos seis, nove e 12 dias, entretanto não apresentou diferença significativa com as temperaturas de 20-30 ºC, nas contagens aos 9 e 12 dias. As sementes de pinhão-manso analisadas apresentaram alta frequência de espécies fúngicas, independente da desinfestação superficial. A incidência de fungos em ordem decrescente foi dos gêneros: Alternaria, Macrophomina, Cladosporium, Colletotrichum, Fusarium, Pestalotiopsis, Phoma, Helminthosporium, Epicocum e Nigrospora a maioria destes fungos apresenta potencial patogênico.

Queixas osteomusculares relacionadas ao trabalho relatadas por mulheres de centro de ressocialização

Considerando as queixas de origem laboral um problema de saúde pública, objetivou-se, com o presente estudo, analisar a freqüência da população que refere queixas osteomusculares e a associação de ocorrência e severidade destas às variáveis antropométricas e de trabalho. Tomou-se 146 mulheres de um centro de ressocialização feminino, que responderam a um questionário validado contendo informações sobre dados antropométricos e queixas osteomusculares relacionadas ao trabalho. O estudo da associação entre e dentro das variáveis foi feito pelo teste de Goodman. Observou-se elevada freqüência de ocorrência de queixas após início de atividade laboral (94,19%). As participantes com necessidade de afastamento apresentaram maiores valores em idade e peso. Queixa acentuada foi mais referida na coluna do tronco. Afastamento foi mais referido para as que trabalhavam há mais tempo. Concluiu-se que é alta a freqüência de queixas relacionadas ao trabalho e que há associação entre maiores valores de peso e de estatura e nível de severidade acentuado; maiores valores de idade e de peso e necessidade de afastamento; níveis acentuados de queixas e região da coluna e entre maior tempo de serviço e necessidade de afastamento.

n-alkanes from Paepalanthus Mart. species (Eriocaulaceae)

Este trabalho apresenta o estudo de substâncias apolares obtidas a partir de plantas pertencentes ao gênero Paepalanthus Mart. (Eriocaulaceae). Hidrocarbonetos alifáticos de cadeias longas lineares foram identificados por CG-DIC e CG-EM. Os resultados indicam que as espécies de Paepalanthus subg. Platycaulon apresentam perfil homogêneo, com cadeias carbônicas de n-alcanos variando de C25 a C31, com a maioria das amostras apresentando freqüências maiores dos homólogos C27 e C29. As espécies do subgênero Paepalocephalus podem ser diferenciadas pela distribuição dos n-alcanos principais. P. macrocephalus, uma espécie da subseção Aphorocaulon, apresenta perfil com alcanos de cadeia ímpar, enquanto P. denudatus e P. polyanthus, espécies da seção Actinocephalus, apresentam perfil bem distinto, com grande número de cadeias mais curtas e alta freqüência de cadeias com número par de carbonos, especialmente P. polyanthus. Os resultados obtidos indicam que a distribuição de nalcanos pode ser útil como caráter taxonômico, assim como as substâncias mais polares, como os flavonóides glicosilados.

Uma análise de semelhanças e diferenças na tradução de textos técnicos, jornalísticos e literários

Por meio da utilização de corpus de textos técnicos, jornalísticos e literários escritos originalmente em inglês e traduzidos para o português, pode-se efetuar uma análise das soluções propostas pelos tradutores ao lidarem com semelhanças e diferenças lingüísticas e culturais dos textos de partida e de chegada. Com esse intuito, aplicou-se o modelo descritivo-comparativo sugerido por Aubert (1984, 1998), o qual se origina das categorias de Vinay e Darbelnet ([1958, 1977] 1995), a fim de, primeiramente, identificar e, depois, classificar os procedimentos ou modalidades empregadas na tradução desses gêneros textuais. Registraram-se como modalidades de maior incidência nos três corpora: a tradução literal, a transposição e a modulação. em virtude de a alta freqüência da tradução literal ocorrer em textos técnicos e, contrariamente ao esperado, incidir com proporção ainda maior em textos jornalísticos, poder-se-ia inferir uma tendência para automatismos na tradução desses dois tipos de textos. Já a necessidade de um emprego acentuado da modulação e da transposição com modulação em textos literários poderia ser decorrente de uma participação mais ativa do tradutor na tentativa de escapar da literalidade e proceder a uma maior reelaboração, a fim de passar características normalmente associadas à linguagem do romance.

Identificação de zonas mortas da cóclea por meio do teste TEN

O audiograma ou o relato do paciente não é suficiente para determinar a presença ou não de zonas mortas na cóclea (ZMC), nem identificar sua extensão. OBJETIVO: Investigar, utilizando o teste TEN, ZMC de indivíduos com perda auditiva neurossensorial (PANS). CEDALVI/ HRAC-USP-Bauru, de agosto de 2003 a fevereiro de 2004. TIPO DE ESTUDO: Estudo de coorte contemporânea com corte transversal. Casuística e Métodos: O TEN foi aplicado nos grupos G1 (5 mulheres com limiares tonais aéreos dentro do padrão de normalidade); G2 (4 mulheres e 5 homens com PANS moderada plana); G3 (19 mulheres e 24 homens com PANS com o grau variando entre leve a profundo). RESULTADOS: Para G1, o valor de TEN para eliminar o tom de teste foi, em média, próximo ao limiar absoluto para todas as freqüências. Não foi observada ZMC em nenhuma das orelhas testadas do G2. Para as 76 orelhas do G3, 6 não apresentaram indício de ZM. CONCLUSÕES: O TEN é efetivo para indicar ZMC em indivíduos com PANS descendente. Há evidência de diferença na detecção do tom puro na presença de ruído entre indivíduos com PANS em altas freqüências e com PANS plana, pois se observou diferença significativa entre o limiar mascarado e absoluto apenas para PANS descendentes e não para as planas.

Emprego do cell block de agarose como método complementar no diagnóstico citológico de tumores mamários caninos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Duffy blood group gene polymorphisms among malaria vivax patients in four areas of the Brazilian Amazon region

Background: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.Methods: the P. vivax identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used.Results: the data show a high frequency of the FYA/FYB genotype, followed by FYB/FYB, FYA/FYA, FYA/FYB-33 and FYB/FYB-33. Low frequencies were detected for the FYA/FY(X), FYB/FY(X), FYX/FY(X) and FYB-33/FYB-33 genotypes. Negative Duffy genotype (FYB-33/FYB-33) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the FY(X)/FYB-33 genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients.Conclusion: the obtained data suggest that individuals with the FYA/FYB genotype have higher susceptibility to malaria. The presence of the FYB-33 allele may be a selective advantage in the population, reducing the rate of infection by P. vivax in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for P. vivax malaria, in particular the Brazilian Amazon region.

On non-ideal simple portal frame structural model: Experimental results under a non-ideal excitation

We present measurements of the non-linear oscillations of a portal frame foundation for a non-ideal motor. We consider a three-time redundant structure with two columns, clamped in their bases and a horizontal beam. An electrical unbalanced motor is mounted at mid span of the beam. Two non-linear phenomena are studied: a) mode saturation and energy transfer between modes; b) interaction between high amplitude motions of the structure and the rotation regime of a real limited power motor. The dynamic characteristics of the structure were chosen to have one-to-two internal resonance between the anti-symmetrical mode (sway motions) and the first symmetrical mode natural frequencies. As the excitation frequency reaches near resonance conditions with the 2nd natural frequency, the amplitude of this mode grows up to a certain level and then it saturates. The surplus energy pumped into the system is transferred to the sway mode, which experiences a sudden increase in its amplitude. Energy is transformed from low amplitude high frequency motion into high amplitude low frequency motion. Such a transformation is potentially dangerous.We consider the fact that real motors, such as the one used in this study, have limited power output. In this case, this energy source is said to be non-ideal, in contrast to the ideal source whose amplitude and frequency are independent of the motion of the structure. Our experimental research detected the Sommerfeld Effect: as the motor accelerates to reach near resonant conditions, a considerable part of its output energy is consumed to generate large amplitude motions of the structure and not to increase its own angular speed. For certain parameters of the system, the motor can get stuck at resonance not having enough power to reach higher rotation regimes. If some more power is available, jump phenomena may occur from near resonance to considerably higher motor speed regimes, no stable motions being possible between these two.

Admittance and dielectric spectroscopy of polycrystalline semiconductors

This text discusses about advantageous, powerful and limitations of admittance and dielectric spectroscopy in the characterization of polycrystalline semiconductors. In the context of polycrystalline semiconductors or dielectric materials, the admittance or dielectric frequency response analyses are shown to be sometimes more useful than impedance spectra analysis, mainly because information on the capacitances or deep trap states are possible to be monitored from admittance or dielectric spectra as a function of dopant concentration or annealing effects. The majority of examples of the application of admittance or dielectric analysis approach were here based on SnO2- and ZnO-based polycrystalline semiconductors devices presenting nonohmic properties. Examples of how to perform the characterization of Schottky barrier in such devices are clearly depicted. The approach is based on findings of the true Mott-Schottky pattern of the barrier by extracting the grain boundary capacitance value from complex capacitance diagram analysis. The equivalent circuit of such kind of devices is mainly consistent with the existence of three parallel elements: the high-frequency limit related to grain boundary capacitances, the complex incremental capacitance at intermediate frequency related to the deep trap relaxation and finally at low frequency region the manifestation of the conductance term representing the dc conductance of the multi-junction device. (c) 2007 Elsevier Ltd. All rights reserved.

Underlying dynamics of typical fluctuations of an emerging market price index: the Heston model from minutes to months

We investigate the Heston model with stochastic volatility and exponential tails as a model for the typical price fluctuations of the Brazilian São Paulo Stock Exchange Index (IBOVESPA). Raw prices are first corrected for inflation and a period spanning 15 years characterized by memoryless returns is chosen for the analysis. Model parameters are estimated by observing volatility scaling and correlation properties. We show that the Heston model with at least two time scales for the volatility mean reverting dynamics satisfactorily describes price fluctuations ranging from time scales larger than 20min to 160 days. At time scales shorter than 20 min we observe autocorrelated returns and power law tails incompatible with the Heston model. Despite major regulatory changes, hyperinflation and currency crises experienced by the Brazilian market in the period studied, the general success of the description provided may be regarded as an evidence for a general underlying dynamics of price fluctuations at intermediate mesoeconomic time scales well approximated by the Heston model. We also notice that the connection between the Heston model and Ehrenfest urn models could be exploited for bringing new insights into the microeconomic market mechanics. (c) 2005 Elsevier B.V. All rights reserved.

Strong and fast phase modulation for quantitative analysis of photorefractive gratings

A new approach for studying photorefractive gratings in two-wave mixing experiments by a phase modulation technique is presented. The introduction of a large-amplitude, high-frequency sinusoidal phase modulation in one of the input beams blurs the interference pattern and provides powerful harmonic signals for accurate measurements of the grating diffraction efficiency eta and the output phase shift rho between the transmitted and diffracted waves. The blurring of the light fringes can be used to suppress the higher spatial harmonics of the grating, allowing a space-charge field with sinusoidal profile to be recorded. Although the presence of such a strong phase modulation affects the beam coupling in a rather complicated way, it is shown that for the special case of equal intensity input beams, the effect of the phase modulation on eta and rho is reduced to a weakening of the coupling strength. The potentialities of the technique are illustrated in a study of refractive-index waves excited by running interference patterns in a Bi12TiO20 crystal. Expressions for the diffraction efficiency and the output phase shift are derived and used to match numerically calculated curves to the experimental data. The theoretical model is supported by the very good data fitting and allows the computation of important material parameters.

Evidence for a respiratory component, similar to mammalian respiratory sinus arrhythmia, in the heart rate variability signal from the rattlesnake, Crotalus durissus terrificus

Autonomic control of heart rate variability and the central location of vagal preganglionic neurones (VPN) were examined in the rattlesnake ( Crotalus durissus terrificus), in order to determine whether respiratory sinus arrhythmia (RSA) occurred in a similar manner to that described for mammals. Resting ECG signals were recorded in undisturbed snakes using miniature datalogging devices, and the presence of oscillations in heart rate (f(H)) was assessed by power spectral analysis (PSA). This mathematical technique provides a graphical output that enables the estimation of cardiac autonomic control by measuring periodic changes in the heart beat interval. At fH above 19 min(-1) spectra were mainly characterised by low frequency components, reflecting mainly adrenergic tonus on the heart. By contrast, at f(H) below 19 min(-1) spectra typically contained high frequency components, demonstrated to be cholinergic in origin. Snakes with a f(H) > 19 min(-1) may therefore have insufficient cholinergic tonus and/or too high an adrenergic tonus acting upon the heart for respiratory sinus arrhythmia ( RSA) to develop. A parallel study monitored f(Hd) simultaneously with the intraperitoneal pressures associated with lung inflation. Snakes with a fH < 19 min(-1) exhibited a high frequency (HF) peak in the power spectrum, which correlated with ventilation rate (f(V)). Adrenergic blockade by propranolol infusion increased the variability of the ventilation cycle, and the oscillatory component of the f(H) spectrum broadened accordingly. Infusion of atropine to effect cholinergic blockade abolished this HF component, confirming a role for vagal control of the heart in matching f(H) and f(V) in the rattlesnake. A neuroanatomical study of the brainstem revealed two locations for vagal preganglionic neurones (VPN). This is consistent with the suggestion that generation of ventilatory components in the heart rate variability (HRV) signal are dependent on spatially distinct loci for cardiac VPN. Therefore, this study has demonstrated the presence of RSA in the HRV signal and a dual location for VPN in the rattlesnake. We suggest there to be a causal relationship between these two observations.

A study of habitat fragmentation in Southeastern Brazil using remote sensing and geographic information systems (GIS)

The purpose of this work was to study fragmentation of forest formations (mesophytic forest, riparian woodland and savannah vegetation (cerrado)) in a 15,774-ha study area located in the Municipal District of Botucatu in Southeastern Brazil (São Paulo State). A land use and land cover map was made from a color composition of a Landsat-5 thematic mapper (TM) image. The edge effect caused by habitat fragmentation was assessed by overlaying, on a geographic information system (GIS), the land use and land cover data with the spectral ratio. The degree of habitat fragmentation was analyzed by deriving: 1. mean patch area and perimeter; 2. patch number and density; 3. perimeter-area ratio, fractal dimension (D), and shape diversity index (SI); and 4. distance between patches and dispersion index (R). In addition, the following relationships were modeled: 1. distribution of natural vegetation patch sizes; 2. perimeter-area relationship and the number and area of natural vegetation patches; 3. edge effect caused by habitat fragmentation, the values of R indicated that savannah patches (R = 0.86) were aggregated while patches of natural vegetation as a whole (R = 1.02) were randomly dispersed in the landscape. There was a high frequency of small patches in the landscape whereas large patches were rare. In the perimeter-area relationship, there was no sign of scale distinction in the patch shapes, In the patch number-landscape area relationship, D, though apparently scale-dependent, tends to be constant as area increases. This phenomenon was correlated with the tendency to reach a constant density as the working scale was increased, on the edge effect analysis, the edge-center distance was properly estimated by a model in which the edge-center distance was considered a function of the to;al patch area and the SI. (C) 1997 Elsevier B.V. B.V.

Phylogeography of the Solanaceae-infecting Basidiomycota fungus Rhizoctonia solani AG-3 based on sequence analysis of two nuclear DNA loci

Background: the soil fungus Rhizoctonia solani anastomosis group 3 (AG-3) is an important pathogen of cultivated plants in the family Solanaceae. Isolates of R. solani AG-3 are taxonomically related based on the composition of cellular fatty acids, phylogenetic analysis of nuclear ribosomal DNA (rDNA) and beta-tubulin gene sequences, and somatic hyphal interactions. Despite the close genetic relationship among isolates of R. solani AG-3, field populations from potato and tobacco exhibit comparative differences in their disease biology, dispersal ecology, host specialization, genetic diversity and population structure. However, little information is available on how field populations of R. solani AG-3 on potato and tobacco are shaped by population genetic processes. In this study, two field populations of R. solani AG-3 from potato in North Carolina (NC) and the Northern USA; and two field populations from tobacco in NC and Southern Brazil were examined using sequence analysis of two cloned regions of nuclear DNA (pP42F and pP89).Results: Populations of R. solani AG-3 from potato were genetically diverse with a high frequency of heterozygosity, while limited or no genetic diversity was observed within the highly homozygous tobacco populations from NC and Brazil. Except for one isolate (TBR24), all NC and Brazilian isolates from tobacco shared the same alleles. No alleles were shared between potato and tobacco populations of R. solani AG-3, indicating no gene flow between them. To infer historical events that influenced current geographical patterns observed for populations of R. solani AG-3 from potato, we performed an analysis of molecular variance (AMOVA) and a nested clade analysis (NCA). Population differentiation was detected for locus pP89 (Phi(ST) = 0.257, significant at P < 0.05) but not for locus pP42F (Phi(ST) = 0.034, not significant). Results based on NCA of the pP89 locus suggest that historical restricted gene flow is a plausible explanation for the geographical association of clades. Coalescent-based simulations of genealogical relationships between populations of R. solani AG-3 from potato and tobacco were used to estimate the amount and directionality of historical migration patterns in time, and the ages of mutations of populations. Low rates of historical movement of genes were observed between the potato and tobacco populations of R. solani AG-3.Conclusion: the two sisters populations of the basidiomycete fungus R. solani AG-3 from potato and tobacco represent two genetically distinct and historically divergent lineages that have probably evolved within the range of their particular related Solanaceae hosts as sympatric species.