431 research outputs found
Cool spots on the surface of the active giant PZ Mon
Based on the multiband (BVRIJHKL) photometric observations of the active red
giant PZ Mon performed for the first time in the winter season of 2017-2018, we
have determined the main characteristics of the spotted stellar surface in a
parametric three-spot model. The unspotted surface temperature is Teff=4730 K,
the temperature of the cool spots is Tspot=3500 K, their relative area is about
41%, and the temperature of the warm spots is Twarm=4500 K with a maximum
relative area up to 20%. The distribution of spots over the stellar surface has
been modeled. The warm spots have been found to be distributed at various
longitudes in the hemisphere on the side of the secondary component and are
most likely a result of its influence.Comment: 5 pages, 7 figure
Evidence for nonallopatric speciation among closely related sympatric Heliotropium species in the Atacama Desert
The genetic structure of populations of closely related, sympatric species may
hold the signature of the geographical mode of the speciation process. In
fully allopatric speciation, it is expected that genetic differentiation
between species is homogeneously distributed across the genome. In
nonallopatric speciation, the genomes may remain undifferentiated to a large
extent. In this article, we analyzed the genetic structure of five sympatric
species from the plant genus Heliotropium in the Atacama Desert. We used
amplified fragment length polymorphisms (AFLPs) to characterize the genetic
structure of these species and evaluate their genetic differentiation as well
as the number of loci subject to positive selection using divergence outlier
analysis (DOA). The five species form distinguishable groups in the genetic
space, with zones of overlap, indicating that they are possibly not completely
isolated. Among-species differentiation accounts for 35% of the total genetic
differentiation (FST = 0.35), and FST between species pairs is positively
correlated with phylogenetic distance. DOA suggests that few loci are subject
to positive selection, which is in line with a scenario of nonallopatric
speciation. These results support the idea that sympatric species of
Heliotropium sect. Cochranea are under an ongoing speciation process,
characterized by a fluctuation of population ranges in response to pulses of
arid and humid periods during Quaternary times
Protein conformational changes and protonation dynamics probed by a single shot using quantum-cascade-laser-based IR spectroscopy
Mid-IR spectroscopy is a powerful and label-free technique to investigate protein reactions. In this study, we use quantum-cascade-laser-based dual-comb spectroscopy to probe protein conformational changes and protonation events by a single-shot experiment. By using a well-characterized membrane protein, bacteriorhodopsin, we provide a comparison between dual-comb spectroscopy and our homebuilt tunable quantum cascade laser (QCL)-based scanning spectrometer as tools to monitor irreversible reactions with high time resolution. In conclusion, QCL-based infrared spectroscopy is demonstrated to be feasible for tracing functionally relevant protein structural changes and proton translocations by single-shot experiments. Thus, we envisage a bright future for applications of this technology for monitoring the kinetics of irreversible reactions as in (bio-)chemical transformations
Sociological analysis of remote work as a new format of current population employment in Russia
The article discusses remote work as a subject of scientific research, describes the factors stimulating the development of distance employment and substantiates the need for a sociological study of this phenomenon in view of the high potential for the impact of changes in forms of employment not only on the labor market, but also on other social structures. Sociologists extremely rarely consider the remote work, despite the increased relevance in recent years, as a subject of study. Scientific publications devoted to remote work as the main type of employment, as a rule, relate to personnel management issues. However, it should be noted that changes in the structure of employment can also affect other social institutions, processes and relationships: the institution of the family, domestic relations, social and professional communications, social mobility, and the very relationship of a person to work. The authors have conducted preliminary monitoring of the media and blogosphere in the Tyumen region and come to the conclusion that, as of today, the applied research methods do not allow to fully reveal the impact of remote employment on all spheres of social life and describe the trends. Therefore, an in-depth sociological analysis of telecommuting with the help of in-depth interviews, interviews with experts, questionnaires to specialists employed in the labor market and representatives of the authorities is required to identify trends, prospects and social consequences
NY Her: possible discovery of negative superhumps
We presents result of CDD photometry for SU UMa dwarf nova NY Her during 6 nights in June 2017 when object was in quiescence.
Light curves clearly show strong amplitude variations in a range of 0Time series analysis revealed a period 0.07141(5) d,
that we identified as the period of possible negative superhumps of NY Her
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