Composition and distribution patterns of chewing lice of two neotropical species of Turdus

We analyzed the prevalence and intensity of chewing lice on two neotropical species of Turdus and identified morphological parameters of birds influencing louse population dynamics. The study was conducted in southernmost Rio Grande do Sul state (RS), Brazil, between July 2009 and June 2010. Chewing lice were collected by dust-ruffling. The prevalence of chewing lice on both species of Turdus was high. Chewing lice from both species of Turdus exhibit similar composition and distribution patterns. However, chewing lice were more abundant on Turdus rufiventris, whereas species richness was higher on Turdus amaurochalinus. Myrsidea and Brueelia were the most prevalent and abundant genera on both host species in all seasons of the year. A predominance of chewing louse females and adults was observed. Aggregated distributions were observed. Body length was the only morphological parameter correlated with louse abundance, suggesting that specimens with a larger body have a higher abundance of lice.     

Systemic Analysis of the Brazilian Production Chain of Semiconductors: Graphic Representation and Leverage Points

The purpose of this article is to analyze systemically the Brazilian production chain of semiconductors. The specific objectives of this article are to represent the chain systemically and to identify key variables and leverage points that can increase the overall performance of the semiconductor industry. The research method is qualitative modelling. Eleven practitioners of the industry answered a questionnaire approaching various aspects of the semiconductor industry in Brazil. By a systemic approach, the complex behavior present in the industry was considered. By content analysis, we identified patterns in the speech of the respondents. Texts fragments allowed the identification of key themes and variables present in the system. The association among key variables and complex behavior helped to build a systemic structure, aimed at representing the main relationships in the system. From the systemic structure, eight leverage points were identified and discussed. The key implications of the findings are the damage that cheap imports make in the local market; the need of strong public policies that include more than tax reduction, but also local conditions, like clusters or technological parks, for the high-tech manufacture; and the promotion of conditions that stimulate private investment in the industry.     

Allosteric function and dysfunction of the prion protein

Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases associated with progressive oligo- and multimerization of the prion protein (PrP^C), its conformational conversion, aggregation and precipitation. We recently proposed that PrP^C serves as a cell surface scaffold protein for a variety of signaling modules, the effects of which translate into wide-range functional consequences. Here we review evidence for allosteric functions of PrP^C, which constitute a common property of scaffold proteins. The available data suggest that allosteric effects among PrP^C and its partners are involved in the assembly of multi-component signaling modules at the cell surface, impose upon both physiological and pathological conformational responses of PrP^C, and that allosteric dysfunction of PrP^C has the potential to entail progressive signal corruption. These properties may be germane both to physiological roles of PrP^C, as well as to the pathogenesis of the TSEs and other degenerative/non-communicable diseases.     

Shigella sonnei genome sequencing and phylogenetic analysis indicate recent global dissemination from Europe

Shigella are human-adapted Escherichia coli that have gained the ability to invade the human gut mucosa and cause dysentery, spreading efficiently via low-dose fecal-oral transmission. Historically, S. sonnei has been predominantly responsible for dysentery in developed countries but is now emerging as a problem in the developing world, seeming to replace the more diverse Shigella flexneri in areas undergoing economic development and improvements in water quality. Classical approaches have shown that S. sonnei is genetically conserved and clonal. We report here whole-genome sequencing of 132 globally distributed isolates. Our phylogenetic analysis shows that the current S. sonnei population descends from a common ancestor that existed less than 500 years ago and that diversified into several distinct lineages with unique characteristics. Our analysis suggests that the majority of this diversification occurred in Europe and was followed by more recent establishment of local pathogen populations on other continents, predominantly due to the pandemic spread of a single, rapidly evolving, multidrug-resistant lineage.     

Mutations in NMNAT1 cause Leber congenital amaurosis with early-onset severe macular and optic atrophy

In addition to its activity in nicotinamide adenine dinucleotide (NAD(+)) synthesis, the nuclear nicotinamide mononucleotide adenyltransferase NMNAT1 acts as a chaperone that protects against neuronal activity-induced degeneration. Here we report that compound heterozygous and homozygous NMNAT1 mutations cause severe neonatal neurodegeneration of the central retina and early-onset optic atrophy in 22 unrelated individuals. Their clinical presentation is consistent with Leber congenital amaurosis and suggests that the mutations affect neuroprotection of photoreceptor cells.     

Genome-wide association analysis identifies three new breast cancer susceptibility loci

Breast cancer is the most common cancer among women. To date, 22 common breast cancer susceptibility loci have been identified accounting for ～8% of the heritability of the disease. We attempted to replicate 72 promising associations from two independent genome-wide association studies (GWAS) in ～70,000 cases and ～68,000 controls from 41 case-control studies and 9 breast cancer GWAS. We identified three new breast cancer risk loci at 12p11 (rs10771399; P = 2.7 × 10(-35)), 12q24 (rs1292011; P = 4.3 × 10(-19)) and 21q21 (rs2823093; P = 1.1 × 10(-12)). rs10771399 was associated with similar relative risks for both estrogen receptor (ER)-negative and ER-positive breast cancer, whereas the other two loci were associated only with ER-positive disease. Two of the loci lie in regions that contain strong plausible candidate genes: PTHLH (12p11) has a crucial role in mammary gland development and the establishment of bone metastasis in breast cancer, and NRIP1 (21q21) encodes an ER cofactor and has a role in the regulation of breast cancer cell growth.     

BBS10 encodes a vertebrate-specific chaperonin-like protein and is a major BBS locus

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous ciliopathy. Although nine BBS genes have been cloned, they explain only 40-50% of the total mutational load. Here we report a major new BBS locus, BBS10, that encodes a previously unknown, rapidly evolving vertebrate-specific chaperonin-like protein. We found BBS10 to be mutated in about 20% of an unselected cohort of families of various ethnic origins, including some families with mutations in other BBS genes, consistent with oligogenic inheritance. In zebrafish, mild suppression of bbs10 exacerbated the phenotypes of other bbs morphants.     

啤酒厂污泥替代营养盐培养钝顶螺旋藻的研究

啤酒厂废水处理后排出的沉淀池剩余活性污泥[1]（以下自称啤酒厂污泥）含粗蛋白20％～30％,磷、铁、钾等藻类培养主要元素含量丰富,同时还含有不少藻类培养所需的微量元素和辅助生长的有机物质,是培养藻类的良好基质[2]．经试验能50％替代营养盐培养钝项螺旋藻而保持其收得率基本不变,利用啤酒厂污泥培养螺旋藻既净化环境,又降低藻类养殖成本[3],是一条有政处理污泥和推广螺旋藻养殖的良好途径．     

基于线性模式的有损伤图像复原技术的研究

提出了一种线性逼近法,应用数字图像处理技术,实现了有损伤图像的复原。结果显示,复原图像质量有显著改善。