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111.
Rebecca T. Trout Fryxell Kimberly Freyman Armando Ulloa Brian Hendricks Dave Paulsen Agricola Odoi Abelardo Moncayo 《PloS one》2015,10(4)
La Crosse encephalitis (LAC) is the leading arboviral disease among children, and was previously limited to the upper Midwest. In 2012 nine pediatric cases of LAC occurred in eastern Tennessee, including one fatal case. In an attempt to identify sites near an active LACv infection and describe the abundance and distribution of potential LACv vectors near a fatal LAC case in the Appalachian region, we initiated an end of season study using a combination of questing and oviposition mosquito traps placed at forty-nine sites consisting of cemeteries and houses within 16 radial kilometers of two pediatric infections. LACv was isolated from three Aedes triseriatus pools collected from cemeteries and spatial clustering analysis identified clusters of Ae. triseriatus and Ae. albopictus populations that overlapped in the same area as the 2012 LACv cases. Results indicate cemeteries are effective sites for monitoring LACv. The role of cemeteries and specific environmental features will be the focus of future investigations. 相似文献
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Kermanshahi Sareh Ghanavati Ghazal Abbasi-Mesrabadi Mobina Gholami Mina Ulloa Luis Motaghinejad Majid Safari Sepideh 《Neurochemical research》2020,45(11):2573-2585
Neurochemical Research - Neurodegenerative disorders are characterized by mitochondrial dysfunction and subsequently oxidative stress, inflammation, and apoptosis that contribute to neuronal... 相似文献
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M. Alejandra Giaveno M. Sofía Urbieta J. Ricardo Ulloa Elena González Toril Edgardo R. Donati 《Microbial ecology》2013,65(2):336-346
A novel thermoacidophilic archaeal strain has been isolated from three geothermal acidic hot springs in Copahue, Argentina. One of the most striking characteristic of ALE1 isolate is its metabolic versatility. It grows on sulphur, tetrathionate, iron (II) and sucrose under aerobic conditions, but it can also develop under anaerobic conditions using iron (III) or sulphur as electron acceptors and sulphur or hydrogen as electron donors autotrophically. A temperature of 75 °C and a pH between 2.5 and 3.0 are strain ALE1 optimal growth conditions, but it is able to oxidise iron (II) even at pH 1.0. Cells are irregular cocci surrounded by a regularly arrayed glycoprotein layer (S-layer). Phylogenetic analysis shows that strain ALE1 belongs to the family Sulfolobaceae in the class Thermoprotei, within the phylum Crenarchaeota. Based on 16S rRNA gene sequence similarity on NCBI database, ALE1 does not have closely related relatives, neither in culture nor uncultured, which is more surprising. Its closest related species are strains of Acidianus hospitalis (91 % of sequence similarity), Acidianus infernus (90 %), Acidianus ambivalens (90 %) and Acidianus manzanensis (90 %). Its DNA base composition of 34.5 %?mol C?+?G is higher than that reported for other Acidianus species. Considering physiological and phylogenetic characteristics of strain ALE1, we considered it to represent a novel species of the genus Acidianus (candidatus “Acidianus copahuensis”). The aim of this study is to physiologically characterise this novel archaea in order to understand its role in iron and sulphur geochemical cycles in the Copahue geothermal area and to evaluate its potential applications in bioleaching and biooxidation. 相似文献
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Phylogenetic analyses today involve dealing with computer files in different formats and often several computer programs. Although some widely used applications have integrated important functionalities for such analyses, they still work with local resources only: input/output files (users have to manage them) and local computing (users have sometimes to leave their programs, on their desktop computers, running for extended periods of time). To address these problems we have developed 'Bosque', a multi-platform client-server software that performs standard phylogenetic tasks either locally or remotely on servers, and integrates the results on a local relational database. Bosque performs sequence alignments and graphical visualization and editing of trees, thus providing a powerful environment that integrates all the steps of phylogenetic analyses. AVAILABILITY: http://bosque.udec.cl 相似文献
117.
Zwirglmaier K Jardillier L Ostrowski M Mazard S Garczarek L Vaulot D Not F Massana R Ulloa O Scanlan DJ 《Environmental microbiology》2008,10(1):147-161
Marine cyanobacteria of the genera Prochlorococcus and Synechococcus are important contributors to global primary production occupying a key position at the base of marine food webs. The genetically diverse nature of each genus is likely an important reason for their successful colonization of vast tracts of the world's oceans, a feature that has led to detailed analysis of the distribution of these genetic lineages at the local and ocean basin scale. Here, we extend these analyses to the global dimension, using new data from cruises in the Pacific, Indian and Arctic Oceans in combination with data from previous studies in the Atlantic Ocean, Arabian Sea, Red Sea and a circumnavigation of the southern hemisphere to form a data set which comprises most of the world's major ocean systems. We show that the distribution patterns of Prochlorococcus and Synechococcus lineages are remarkably similar in different ocean systems with comparable environmental conditions, but producing a strikingly different 'signature' in the four major ocean domains or biomes (the Polar Domain, Coastal Boundary Domain, Trade Winds Domain and Westerly Winds Domain). This clearly reiterates the idea of spatial partitioning of individual cyanobacterial lineages, but at the global scale. 相似文献
118.
Bioenergy production and sustainable development: science base for policymaking remains limited 下载免费PDF全文
Carmenza Robledo‐Abad Hans‐Jörg Althaus Göran Berndes Simon Bolwig Esteve Corbera Felix Creutzig John Garcia‐Ulloa Anna Geddes Jay S. Gregg Helmut Haberl Susanne Hanger Richard J. Harper Carol Hunsberger Rasmus K. Larsen Christian Lauk Stefan Leitner Johan Lilliestam Hermann Lotze‐Campen Bart Muys Maria Nordborg Maria Ölund Boris Orlowsky Alexander Popp Joana Portugal‐Pereira Jürgen Reinhard Lena Scheiffle Pete Smith 《Global Change Biology Bioenergy》2017,9(3):541-556
The possibility of using bioenergy as a climate change mitigation measure has sparked a discussion of whether and how bioenergy production contributes to sustainable development. We undertook a systematic review of the scientific literature to illuminate this relationship and found a limited scientific basis for policymaking. Our results indicate that knowledge on the sustainable development impacts of bioenergy production is concentrated in a few well‐studied countries, focuses on environmental and economic impacts, and mostly relates to dedicated agricultural biomass plantations. The scope and methodological approaches in studies differ widely and only a small share of the studies sufficiently reports on context and/or baseline conditions, which makes it difficult to get a general understanding of the attribution of impacts. Nevertheless, we identified regional patterns of positive or negative impacts for all categories – environmental, economic, institutional, social and technological. In general, economic and technological impacts were more frequently reported as positive, while social and environmental impacts were more frequently reported as negative (with the exception of impacts on direct substitution of GHG emission from fossil fuel). More focused and transparent research is needed to validate these patterns and develop a strong science underpinning for establishing policies and governance agreements that prevent/mitigate negative and promote positive impacts from bioenergy production. 相似文献
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We are reporting computational studies of several genotyped strains of astrovirus isolated in Colombia which we have genotyped using the 348-bp segment located between nucleotides 258 and 606 close to the amino terminal region of the complete ORF 2. By biocomputational techniques this 348-bp segment from the different strains was translated into an amino acid sequence. The sequences were aligned and compared in order to build a dendrogram. Our results show that the 348 bp and the 116 amino acid peptides cluster in a very conservative way, showing slight genetic variations between them. This slight sequence variability does not allow us to identify common amino acid substitution patterns shared by all members of each HAstV specific type, thus suggesting that antigenic epitopes are probably located outside the 116 peptide fragment of this capsid protein. These results show that there is little recombination among different regions of the ORF2, thus suggesting that this genotyping method should continue to be useful for serotyping HAstV isolates. 相似文献