Estudo para determinação da frequência de deformidade do mento em Chironomus sancticaroli (Diptera: chironomidae) em cultura de laboratório

The midge Chironomus sancticaroli (Diptera: Chironomidae) has been used in ecotoxicological tests because it is sensitive to a variety of inorganic pollutants. Among the parameters used to evaluate the toxicity of a substance is the frequency of mentum deformity, which is part of the oral system of this organism. However, there is still no consensus on the baseline level (percentage) of acceptable deformities in laboratory cultures not exposed to pollutants. The determination of this variable is important to ensure the validity of bioassays and to compare cultures from different research and teaching institutions. Once this value is established, it will also be used to monitor the quality of organisms cultured, since factors such as inbreeding could increase the frequency of mentum deformity. Thus, the objective of this study was to quantify the percentage of mentum deformity in the fourth instar of C. sancticaroli larvae from the culture of the Laboratory of Aquatic Ecosystems, at Embrapa Meio Ambiente. The average frequency of mentum deformity obtained was 6,63%. It is believed that factors such as the renewal of the culture with the inclusion of spawns from the laboratories of other institutions, as well as the control of the quality of the dilution water and the sediment of the breeding may have contributed to a low frequency of mentum deformity of the culture observed in this study.142sensível a uma variedade de poluentes inorgânicos. Um dos parâmetros utilizados para avaliar a toxicidade de uma substância é a frequência de deformidade do mento, que faz parte do sistema oral deste organismo. Entretanto, ainda não há consenso a respeito do nível basal (porcentagem) de deformidade aceitável em culturas de laboratório não expostas a poluentes. A determinação desta variável é importante para assegurar a validade de bioensaios e comparar culturas de diferentes instituições de pesquisa e ensino. Uma vez estabelecido, este número também será usado para o controle da qualidade dos organismos criados, já que fatores como o endocruzamento poderiam aumentar a frequência de deformidade do mento. Assim, o objetivo deste estudo foi quantificar a porcentagem de deformidade do mento em larvas de quarto instar de C. sancticaroli de cultura do Laboratório de Ecossistemas Aquáticos da Embrapa Meio Ambiente. A média de frequência de deformidade obtida para a cultura foi de 6,63%. Acredita-se que fatores como a renovação da cultura com a inclusão de desovas de laboratórios de outras instituições, assim como o controle da qualidade da água de diluição e do sedimento da criação, podem ter contribuído para uma baixa frequência de deformidade do mento da cultura

Polarisation measurements with a CdTe pixel array detector for Laue hard X-ray focusing telescopes

Polarimetry is an area of high energy astrophysics which is still relatively unexplored, even though it is recognized that this type of measurement could drastically increase our knowledge of the physics and geometry of high energy sources. For this reason, in the context of the design of a Gamma-Ray Imager based on new hard-X and soft gamma ray focusing optics for the next ESA Cosmic Vision call for proposals (Cosmic Vision 2015-2025), it is important that this capability should be implemented in the principal on-board instrumentation. For the particular case of wide band-pass Laue optics we propose a focal plane based on a thick pixelated CdTe detector operating with high efficiency between 60-600 keV. The high segmentation of this type of detector (1-2 mm pixel size) and the good energy resolution (a few keV FWHM at 500 keV) will allow high sensitivity polarisation measurements (a few % for a 10 mCrab source in 106s) to be performed. We have evaluated the modulation Q factors and minimum detectable polarisation through the use of Monte Carlo simulations (based on the GEANT 4 toolkit) for on and off-axis sources with power law emission spectra using the point spread function of a Laue lens in a feasible configuration.Comment: 10 pages, 6 pages. Accepted for publication in Experimental Astronom

Phase-resolved Photoacoustic Spectroscopy And Epr Investigation Of Mno2- And Coo-doped Soda-lime Glasses

A discussion on the use of the phase shifts of the photoacoustic signal of different constituents of a composite sample for resolving their individual spectra is presented. It is experimentally shown that as long as we are interested in a qualitative analysis the method is simple and fast. For a quantitative analysis in which the nonradiative relaxation time and the characteristic diffusion time within the optical-absorption depth are sought, the method presents some limitations. This is demonstrated using MnO2- and CoO-doped soda-lime silica glass samples. © 1989 The American Physical Society.40318801884CAS; Chinese Academy of Sciences; DFG; Chinese Academy of Sciences; NRF; Chinese Academy of Sciences; NSFC; Chinese Academy of Sciences; PSI; Chinese Academy of Sciences; RAS; Chinese Academy of Sciences; RFBR; Chinese Academy of Sciences; RPF; Chinese Academy of Sciences; STFC; Chinese Academy of Science

Amplification of SOX4 promotes PI3K/Akt signaling in human breast cancer

Purpose: The PI3K/Akt signaling axis contributes to the dysregulation of many dominant features in breast cancer including cell proliferation, survival, metabolism, motility, and genomic instability. While multiple studies have demonstrated that basal-like or triple-negative breast tumors have uniformly high PI3K/Akt activity, genomic alterations that mediate dysregulation of this pathway in this subset of highly aggressive breast tumors remain to be determined. Methods: In this study, we present an integrated genomic analysis based on the use of a PI3K gene expression signature as a framework to analyze orthogonal genomic data from human breast tumors, including RNA expression, DNA copy number alterations, and protein expression. In combination with data from a genome-wide RNA-mediated interference screen in human breast cancer cell lines, we identified essential genetic drivers of PI3K/Akt signaling. Results: Our in silico analyses identified SOX4 amplification as a novel modulator of PI3K/Akt signaling in breast cancers and in vitro studies confirmed its role in regulating Akt phosphorylation. Conclusions: Taken together, these data establish a role for SOX4-mediated PI3K/Akt signaling in breast cancer and suggest that SOX4 may represent a novel therapeutic target and/or biomarker for current PI3K family therapies

Influência da consociação com diferentes trevos, da rega e da variedade na produção e qualidade do azevém italiano.

Havendo alguma evidência de que as leguminosas podem beneficiar as gramíneas pela transferência de azoto fixado seria de todo o interesse utilizar consociações em vez de azevém em estreme fertilizado com azoto. Como conclusões gerais, podemos referir que a utilização do trevo squarroso, em consociação com o azevém anual, se mostrou vantajosa, comparativamente aos outros trevos, pois mostrou tendência para apresentar valores mais elevados de produção total de matéria seca, proteína bruta e matéria seca digestível. Porém, as máximas produções foram obtidas com o azevém em estreme fertilizado com 100 kg/ha de azoto à sementeira e após cada corte. No ensaio comparativo entre diferentes dotações de rega e sequeiro verificou-se que mesmo a dotação mais baixa (25% da CC) permitiu duplicar o número de cortes. Em face dos resultados desta actividade, pode concluir-se que a rega pode contribuir, de forma muito significativa, para aumentar a produção e melhorar a qualidade da forragem produzida. A existência de regadio na região, ainda que com pouca água, é fundamental para regularizar a curva de produção de erva nas explorações pecuárias pois além de maiores produções, em quantidade e qualidade, o número de cortes também pode duplicar. A decisão de regar ou não vai depender da viabilidade económica. Relativamente à utilização da variedade bianual em vez da anual, parece não haver vantagem em condições de regadio pois, além de se ter revelado menos eficiente a utilizar a água, cresce pouco no Verão devido às elevadas temperaturas não se justificando, por isso, continuar a regar. Sem humidade no solo, a sua persistência é afectada pelo que não se torna viável continuar a explorá-la no ano seguinte. Assim, uma vez que a água é um recurso cada vez mais escasso e caro, parece que a melhor escolha é o azevém anual com o tratamento de rega mais baixo. No entanto, caso não exista água disponível para regar, a variedade bianual parece mais vantajosa

Photoacoustic And Esr Studies Of Iron-doped Soda-lime Glasses: Thermal Diffusivity

The photoacoustic technique is used to measure the thermal diffusivity of iron-doped soda-lime glasses. To explain the thermal diffusivity behavior as a function of the iron content in the samples, electron-spin-resonance data were used. It is concluded that the main reason for the observed changes in the thermal diffusivity is the ferric ion entering substitutionally at the Si4+ sites. © 1989 The American Physical Society.40117912791

Gender and age differences in polysomnography findings and sleep complaints of patients referred to a sleep laboratory

Our objective was to examine the effet of gender on the sleep pattern of patients referred to a sleep laboratory. The data (questionnaires and polysomnographic recordings) were collected from a total of 2365 patients (1550 men and 815 women). The polysomnography permits an objective assessment of the sleep pattern. We included only polysomnography exams obtained with no more than one recording system in order to permit normalization of the data. Men had a significantly higher body mass index than women (28.5 ± 4.8 vs 27.7 ± 6.35 kg/m²) and had a significantly higher score on the Epworth Sleepiness Scale (10.8 ± 5.3 vs 9.5 ± 6.0), suggesting daytime sleepiness. Women had a significantly higher sleep latency than men, as well as a higher rapid eye movement (REM) latency. Men spent more time in stages 1 (4.6 ± 4.1 vs 3.9 ± 3.8) and 2 (57.0 ± 10.5 vs 55.2 ± 10.1) of non-REM sleep than women, whereas women spent significantly more time in deep sleep stages (3 and 4) than men (22.6 ± 9.0 vs 19.9 ± 9.0). The apnea/hypopnea and arousal indexes were significantly higher and more frequent in men than in women (31.0 ± 31.5 vs 17.3 ± 19.7). Also, periodic leg movement index did not differ significantly between genders, but rather differed among age groups. We did not find significant differences between genders in the percentage of REM sleep and sleep efficiency. The results of the current study suggest that there are specific gender differences in sleep pattern.1067107

A case study undertaken recycling & reuse of glass fiber reinforced thermoset polumer wastes of composite materials industry

Glass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: crosslinked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, efforts were made in order to recycle grinded GFRP waste, proceeding from pultrusion production scrap, into new and sustainable composite materials. For this purpose, GFRP waste recyclates, were incorporated into polyester based mortars as fine aggregate and filler replacements at different load contents and particle size distributions. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified polymer mortars. Results revealed that GFRP waste filled polymer mortars present improved flexural and compressive behaviour over unmodified polyester based mortars, thus indicating the feasibility of the GFRP industrial waste reuse into concrete-polymer composite materials