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XMPP for cloud computing in bioinformatics supporting discovery and invocation of asynchronous web services 总被引:1,自引:0,他引:1
Background
Life sciences make heavily use of the web for both data provision and analysis. However, the increasing amount of available data and the diversity of analysis tools call for machine accessible interfaces in order to be effective. HTTP-based Web service technologies, like the Simple Object Access Protocol (SOAP) and REpresentational State Transfer (REST) services, are today the most common technologies for this in bioinformatics. However, these methods have severe drawbacks, including lack of discoverability, and the inability for services to send status notifications. Several complementary workarounds have been proposed, but the results are ad-hoc solutions of varying quality that can be difficult to use. 相似文献23.
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Summer distribution of Red-legged Partridges Alectoris rufa in relation to water availability on Mediterranean farmland 总被引:1,自引:0,他引:1
The suggestion that the summer distribution of Red-legged Partridges Alectoris rufa in the Mediterranean region is determined by the availability of surface water was examined on the agricultural farm, Alto Alentejo, southern Portugal. Partridge coveys were surveyed between 15 July and 15 August in 1993 and 1994. Using a vector-based Geographic Information System, we assessed, for each covey location and for the locations of a double number of random points, the distance to the nearest water point, distance to field boundaries, distance to water lines and land use classes. Univariate comparisons were made between the two groups of locations, and three multivariate logistic models were fitted through forward stepwise selection to the 1993, 1994 and pooled data sets to estimate the probability of sighting partridge coveys in the study area. Distance to water was significantly lower for partridge locations than for random points in both years and was the only variable selected for all logistic models. Apart from water availability, Red-legged Partridge locations were also affected by land use and distance to field boundaries. 相似文献
26.
Zea ribosomal repeat evolution and substitution patterns 总被引:2,自引:1,他引:1
Zea and Tripsacum nuclear ribosomal internal transcribed spacer (ITS)
sequences were used to evaluate patterns of concerted evolution, rates of
substitutions, patterns of methylation-induced deamination, and structural
constraints of the ITS. ITS pseudogenes were identified by their
phylogenetic position, differences in nucleotide composition, extensive
deamination at ancestral methylation sites, and substitutions resulting in
low-stability secondary RNA structures. Selection was important in shaping
the kinds of polymorphisms and substitutions observed in the ITS. ITS
substitution rates were significantly different among the Zea taxa.
Deamination of cytosines at methylation sites was a potent mutation source,
but selection appeared to maintain high methylation site density throughout
the ribosomal repeat except for the gene promoter. Nucleotide divergence
statistics identified selectively constrained regions at the 5' ends of the
ITS1 and ITS2.
相似文献
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28.
Concerted transpositions of mobile genetic elements coupled with fitness changes in Drosophila melanogaster 总被引:3,自引:0,他引:3
Pasyukova EG; Belyaeva ES; Kogan GL; Kaidanov LZ; Gvozdev VA 《Molecular biology and evolution》1986,3(4):299-312
In an inbred low-activity (LA) strain of Drosophila melanogaster with a low
level of fitness and a complex of inadaptive characters, in situ
hybridization reveals an invariant pattern of distribution of three
copia-like elements (mdg-1, mdg-3, and copia). Rare, spontaneous, multiple
transpositions of mobile elements in the LA strain were shown to be coupled
with a drastic increase of fitness. A changed pattern of various types of
mobile elements was also observed on selecting the LA strain for higher
fitness. High-fitness strains show transpositions of mobile elements to
definite chromosomal sites ("hot spots"). Concerted changes in the location
of three different mobile elements were found to be coupled with an
increase of fitness. The mdg-1 distribution patterns were also examined in
two low-fitness strains independently selected from the high-fitness ones.
Fitness decrease was accompanied by mdg-1 excision from the hot spots of
their location usually detected in the high-fitness strains. The results
suggest the existence of a system of adaptive transpositions of mobile
elements that takes part in fitness control.
相似文献
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NUNO NEGRÕES PEDRO SARMENTO JOANA CRUZ CATARINA EIRA ELOY REVILLA CARLOS FONSECA RAHEL SOLLMANN NATÁLIA M. TǑRRES MARIANA M. FURTADO ANAH T. A. JÁCOMO LEANDRO SILVEIRA 《The Journal of wildlife management》2010,74(6):1195-1203
Abstract: We used remotely triggered cameras to collect data on Puma (Puma concolor) abundance and occupancy in an area of tropical forest in Brazil where the species' status is poorly known. To evaluate factors influencing puma occupancy we used data from 5 sampling campaigns in 3 consecutive years (2005 to 2007) and 2 seasons (wet and dry), at a state park and a private forest reserve. We estimated puma numbers and density for the 2007 sampling data by developing a standardized individual identification method. We based individual identification on 1) time-stable parameters (SP; physical features that do not change over time), and 2) time-variable parameters (VP; marks that could change over time such as scars and botfly marks). Following individual identification we established a capture-recapture history and analyzed it using closed population capture-mark-recapture models. Puma capture probability was influenced by camera placement (roads vs. trails), sampling year, and prey richness. Puma occupancy was positively associated with species richness and there was a correlation between relative puma and jaguar (Panthera onca) abundance. Identifications enabled us to generate 8 VP histories for each photographed flank, corresponding to 8 individuals. We estimated the sampled population at 9 pumas (SE = 1.03, 95% CI = 8–10 individuals) translating to a density of 3.40 pumas/100 km2. Information collected using camera-traps can effectively be used to assess puma population size in tropical forests. As habitat progressively disappears and South American felines become more vulnerable, our results support the critical importance of private forest reserves for conservation. 相似文献