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Neurons in area 17 of cat visual cortex display oscillatory responses that can synchronize across spatially separate columns in a stimulus-specific way. Response synchronization has now been shown to occur also between neurons in area 17 of the right and left cerebral hemispheres. This synchronization was abolished by section of the corpus callosum. Thus, the response synchronization is mediated by corticocortical connections. These data are compatible with the hypothesis that temporal synchrony of neuronal discharges serves to bind features within and between the visual hemifields.  相似文献   
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Lupine flour, protein, and fiber have become common ingredients in food products. The association of lupine-related allergic incidents with peanut allergy is a cause for concern as the latter may bring about severe reactions. In this study, a hybridization probe-based real-time PCR assay for the detection of lupine DNA in foods was developed. Particular attention was paid to the specificity of the method, which was verified by analysis of DNA extracts from more than 50 potential food ingredients such as legumes, cereals, seeds, nuts, spices, fruits, and meat. The limit of detection of the method was determined as 0.1 mg/kg. The successful detection of the presence/absence of lupine DNA in 20 samples proved the suitability of the assay for the analysis of frequently encountered food matrices.  相似文献   
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The current procedures to assess the safety of food and feed derived from modern biotechnology include the investigation of possible unintended effects. To improve the probability of detecting unintended effects, profiling techniques such as proteomics are currently tested as complementary analytical tools to the existing safety assessment. An optimized two-dimensional gel electrophoresis (2DE) method was used as a proteomics approach to investigate insertional and pleiotropic effects on the proteome due to genetic engineering. Twelve transgenic Arabidopsis thaliana lines were analyzed by 2DE, and their seed proteomes were compared to that of their parental line as well as to 12 Arabidopsis ecotype lines. The genetic modification of the Arabidopsis lines, using three different genes and three different promoters, did not cause unintended changes to the analyzed seed proteome. Differences in spot quantity between transgenic and nontransgenic lines fell in the range of values found in the 12 Arabidopsis ecotype lines or were related to the introduced gene.  相似文献   
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Systematic mapping studies provide a snapshot of the literature based on systematic literature searches. In this systematic mapping study, the original research that links reforestation and livelihoods in the tropics was mapped and analysed to identify the trends, biases and gaps in the literature. In total, 339 papers from 92 journals were identified. Agroforestry Systems was the journal in which articles were most frequently published, and Cameroon and Indonesia the most frequently studied countries. The greatest number of authors came from the USA, and authors were most commonly affiliated with ICRAF. A limited collaboration between research groups in the tropical regions was identified. Anthropology and Social Sciences were the most frequent areas of research, especially in Africa. Latin America had more technical studies and more publications discussing payment for environmental services than the other regions. Based on the temporal analysis of the main terms in abstracts of the publications included, it was found that agriculture-related terms and terms related to the human component in the landscape were consistently prevalent in the literature relating reforestation and livelihoods throughout time. Agroforestry systems were especially important in small-scale reforestation and livelihoods. Trends, biases and gaps were discussed. Broader cooperation between tropical regions and between clusters of authors would be beneficial for research and practice.  相似文献   
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A metabolite profiling methodology was developed using rice as model crop. The approach is based on consecutive extraction of lipids and polar compounds and subsequent fractionations of both extracts. Transesterification‐solid phase extraction (lipids) and selective hydrolysis of silylated derivatives (polar compounds) are applied to separate major from minor constituents. The method covers a broad spectrum of chemical classes. Preliminary investigation of the four fractions by gas chromatography/mass spectrometry (GC/MS) analysis of silylated derivatives identified more than 100 compounds. This unbiased approach can serve as an additional analytical tool for the safety assessment of genetically modified crops and may help to increase the chance to detect unintended effects due to the application of recombinant DNA techniques.  相似文献   
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