639 research outputs found
Tendencies of interaction between Russian universities and companies implementing innovative development programs
The main aim of this article is to analyze key indicators and trends of global innovative development and their role in development. Attention is given to the consideration of several mechanisms of interaction between universities and state companies, with concrete measures and steps that can be used in economic policy. The authors analyze the real experience of the Russian economy now. Based on collected data for the total volume of R&D, revenues and the number of patents, regression models were constructed to determine the relationship between the named indicators. Recommendations and innovative ideas to improve the economic policy are given to achieve the goals and to justify the use of mechanisms of "compulsion to innovate" in state companies for the implementation of more productive development programs.peer-reviewe
Multiple hybridization events between Drosophila simulans and Drosophila mauritiana are supported by mtDNA introgression
The study of speciation has advanced considerably in the last decades because of the increased application of molecular tools. In particular, the quantification of gene flow between recently diverged species could be addressed. Drosophila simulans and Drosophila mauritiana diverged, probably allopatrically, from a common ancestor approximately 250 000 years ago. However, these species share one mitochondrial DNA (mtDNA) haplotype indicative of a recent episode of introgression. To study the extent of gene flow between these species, we took advantage of a large sample of D. mauritiana and employed a range of different markers, i.e. nuclear and mitochondrial sequences, and microsatellites. This allowed us to detect two new mtDNA haplotypes (MAU3 and MAU4). These haplotypes diverged quite recently from haplotypes of the siII group present in cosmopolitan populations of D. simulans. The mean divergence time of the most diverged haplotype (MAU4) is approximately 127 000 years, which is more than 100 000 years before the assumed speciation time. Interestingly, we also found some evidence for gene flow at the nuclear level because an excess of putatively neutral loci shows significantly reduced differentiation between D. simulans and D. mauritiana. Our results suggest that these species are exchanging genes more frequently than previously thought
A new technique for elucidating -decay schemes which involve daughter nuclei with very low energy excited states
A new technique of elucidating -decay schemes of isotopes with large
density of states at low excitation energies has been developed, in which a
Broad Energy Germanium (BEGe) detector is used in conjunction with coaxial
hyper-pure germanium detectors. The power of this technique has been
demonstrated on the example of 183Hg decay. Mass-separated samples of 183Hg
were produced by a deposition of the low-energy radioactive-ion beam delivered
by the ISOLDE facility at CERN. The excellent energy resolution of the BEGe
detector allowed rays energies to be determined with a precision of a
few tens of electronvolts, which was sufficient for the analysis of the
Rydberg-Ritz combinations in the level scheme. The timestamped structure of the
data was used for unambiguous separation of rays arising from the
decay of 183Hg from those due to the daughter decays
Marx, the labour theory of value and the transformation problem
This article reconsiders what Marx says about the transformation problem in Chapter IX of Capital Volume III, in the light of Marx's claim, made in Capital Volume I, that the value of a commodity is determined by the socially necessary labour time that goes into its production. The article criticises the traditional way of thinking about the transformation problem, according to which what Marx is doing in Chapter IX is considering the transformation of values into prices ('prices of production'). I argue that Marx's prices of production may be thought of as modified values. The discussion in Chapter IX is usually seen as a supplement to the labour theory of value. On this view its purpose is to explain how and why the prices of commodities sometimes deviate from their values. Against this view, the paper argues that Marx's remarks in Chapter IX can be seen as an elaboration on or development of the labour theory of value. It is a refinement of the account offered in Capital Volume I, which takes into consideration what Marx had in mind there when he introduced the notion of socially necessary as opposed to actual labour-time. The paper draws attention to the importance of Marx's distinction between the individual value of a commodity (determined by actual labour-time) and its social value (determined by socially necessary labour-time). It also draws attention to the methodological difficulties that are generated by any attempt to read Marx in this way
Plasma Magnetohydrodynamics and Energy Conversion
Contains reports on seven research projects.U. S. Air Force (Aeronautical Systems Division) under Contract AF33 (615)-1083 with the Air Force Aero Propulsion Laboratory, Wright-Patterson Air Force Base, OhioNational Science Foundation (Grant GK-57
Plasma Magnetohydrodynamics and Energy Conversion
Contains research objectives and reports on x research projects.National Science Foundation under Grant G-9330U.S. Air Force (Aeronautical Systems Division) under Contract AF33(616)-7624 with the Flight Accessories Laboratory, Wright-Patterson Air Force Base, Ohi
Plasma Magnetohydrodynamics and Energy Conversion
Contains reports on eight research projects.National Science Foundation (Grant G-24073)United States Air Force, Aeronautical Systems Division, Aeronautical Accessories Laboratory, Wright-Patterson Air Force Base (Contract AF33(616)-7624)United States Air Force, Office of Scientific Research of the Office of Aerospace Research (Research Grant No. 62-308
The surprising negative correlation of gene length and optimal codon use - disentangling translational selection from GC-biased gene conversion in yeast
<p>Abstract</p> <p>Background</p> <p>Surprisingly, in several multi-cellular eukaryotes optimal codon use correlates negatively with gene length. This contrasts with the expectation under selection for translational accuracy. While suggested explanations focus on variation in strength and efficiency of translational selection, it has rarely been noticed that the negative correlation is reported only in organisms whose optimal codons are biased towards codons that end with G or C (-GC). This raises the question whether forces that affect base composition - such as GC-biased gene conversion - contribute to the negative correlation between optimal codon use and gene length.</p> <p>Results</p> <p>Yeast is a good organism to study this as equal numbers of optimal codons end in -GC and -AT and one may hence compare frequencies of optimal GC- with optimal AT-ending codons to disentangle the forces. Results of this study demonstrate in yeast frequencies of GC-ending (optimal AND non-optimal) codons decrease with gene length and increase with recombination. A decrease of GC-ending codons along genes contributes to the negative correlation with gene length. Correlations with recombination and gene expression differentiate between GC-ending and optimal codons, and also substitution patterns support effects of GC-biased gene conversion.</p> <p>Conclusion</p> <p>While the general effect of GC-biased gene conversion is well known, the negative correlation of optimal codon use with gene length has not been considered in this context before. Initiation of gene conversion events in promoter regions and the presence of a gene conversion gradient most likely explain the observed decrease of GC-ending codons with gene length and gene position.</p
The scale of population structure in Arabidopsis thaliana
The population structure of an organism reflects its evolutionary history and influences its evolutionary trajectory. It constrains the combination of genetic diversity and reveals patterns of past gene flow. Understanding it is a prerequisite for detecting genomic regions under selection, predicting the effect of population disturbances, or modeling gene flow. This paper examines the detailed global population structure of Arabidopsis thaliana. Using a set of 5,707 plants collected from around the globe and genotyped at 149 SNPs, we show that while A. thaliana as a species self-fertilizes 97% of the time, there is considerable variation among local groups. This level of outcrossing greatly limits observed heterozygosity but is sufficient to generate considerable local haplotypic diversity. We also find that in its native Eurasian range A. thaliana exhibits continuous isolation by distance at every geographic scale without natural breaks corresponding to classical notions of populations. By contrast, in North America, where it exists as an exotic species, A. thaliana exhibits little or no population structure at a continental scale but local isolation by distance that extends hundreds of km. This suggests a pattern for the development of isolation by distance that can establish itself shortly after an organism fills a new habitat range. It also raises questions about the general applicability of many standard population genetics models. Any model based on discrete clusters of interchangeable individuals will be an uneasy fit to organisms like A. thaliana which exhibit continuous isolation by distance on many scales
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