Superbroad Component in Emission Lines of SS 433

We have detected new components in stationary emission lines of SS 433; these are the superbroad components that are low-contrast substrates with a width of 2000--2500 km s-1 in He I $\lambda4922$ and H$\beta$ and 4000--5000 km s-1 in He II $\lambda4686$. Based on 44 spectra taken during four years of observations from 2003 to 2007, we have found that these components in the He II and He I lines are eclipsed by the donor star; their behavior with precessional and orbital phases is regular and similar to the behavior of the optical brightness of SS 433. The same component in H$\beta$ shows neither eclipses nor precessional variability. We conclude that the superbroad components in the helium and hydrogen lines are different in origin. Electron scattering is shown to reproduce well the superbroad component of H$\beta$ at a gas temperature of 20--35 kK and an optical depth for Thomson scattering $\tau \approx$ 0.25--0.35. The superbroad components of the helium lines are probably formed in the wind from the supercritical accretion disk. We have computed a wind model based on the concept of Shakura-Sunyaev supercritical disk accretion. The main patterns of the He II line profiles are well reproduced in this model: not only the appearance of the superbroad component but also the evolution of the central two-component part of the profile of this line during its eclipse by the donor star can be explained.Comment: 17 pages, 13 figures, 2 tables, published in Astronomy Letters, 2013, vol. 39, N 12, pp. 826 - 84

Magneto-optical response enhanced by Mie resonances in nanoantennas

Control of light by an external magnetic field is one of the important methods for modulation of its intensity and polarisation. Magneto-optical effects at the nanoscale are usually observed in magnetophotonic crystals, nanostructured hybrid materials or magnetoplasmonic crystals. An indirect action of an external magnetic field (e.g. through the Faraday effect) is explained by the fact that natural materials exhibit negligible magnetism at optical frequencies. However, the concept of metamaterials overcome this limitation imposed by nature by designing artificial subwavelength meta-atoms that support a strong magnetic response, usually termed as optical magnetism, even when they are made of nonmagnetic materials. The fundamental question is what would be the effect of the interaction between an external magnetic field and an optically-induced magnetic response of metamaterial structures. Here we make the first step toward answering this fundamental question and demonstrate the multifold enhancement of the magneto-optical response of nanoantenna lattices due to the optical magnetism.Comment: 7 pages, 5 figure

Shelf life extension of minimally processed vegetables using combinations of bacterial bioprotection and modified atmosphere packaging

The objective of the work: to study the effect of combination of bacterial bioprotective cultures and modified atmosphere packaging for prolonging the refrigerated storage period of minimally processed vegetables. Sweet pepper, zucchini, eggplant, celery stalks were used for preparation of minimally processed vegetables. SafePro® bio-products from Chr. Hansen (Denmark) containing strains of Lactobacillus sakei, Pediococcus acidilactici, Lactobacillus сurvatus, Leuconostoc carnosum were used as bioconservatives. For packaging minimally processed vegetables, the bags made of flat multilayer PA/adhesive/PE films and composite PET/A1/PE film material were used. The bags were filled with gas mixtures including nitrogen and carbon dioxide. Storage of packaged minimally processed vegetables was carried out in a refrigerator at a temperature of (4 ± 2) °C for 16 days. The viability of cultures Lactobacillus sakei, Pediococcus acidilactici, Lactobacillus curvatus, Leuconostoc carnosum in modified atmosphere packaging was studied. It was revealed that the gas mixture of 60% nitrogen and 40% carbon dioxide and the culture of Lactobacillus sakei contribute to the preservation of the quality of fresh-cutsweet pepper, eggplant and zucchini, and Leuconostoc carnosum is the more effective for celery storing. In the process of refrigerated storage for 14 days, the solids content in the experimental samples increased 1.3–2.1 times, the loss of organic substances was 26–50%, depending on the type of vegetables. The developed technology for the refrigeration preservation of minimally processed vegetables using bio-products treatment and in modified atmosphere packaging made it possible to increase the shelf life of fresh-cut vegetables by 2 times

From global corruption paradigm to the study of informal practices: outsiders vs. insiders/ От глобальной коррупционной парадигмы к изучению неформальных практик: различие в подходах аутсайдеров и инсайдеров

В статье представлен сравнительный анализ двух подходов: коррупционной парадигмы как взгляда аутсайдеров, применяющих универсальные суждения к разным обществам, и анализа неформальных практик, реконструирующего взгляд инсайдеров, их понимание мотивов и смыслов коррупционных практик. Коррупционная парадигма, получившая широкое распространение в 1990-е годы, базируется на трех предположениях: коррупцию можно четко определить, измерить и преодолеть. Такой подход лежит в основе международных мониторингов и стимулирует активную антикоррупционную политику. В статье систематизирована критика коррупционной парадигмы. Сделан вывод о том, что провалы антикоррупционных кампаний связаны не столько с дефицитом политической воли, сколько с недостаточностью знаний о социокультурной укорененности коррупции, предложены пути интеграции коррупционной парадигмы с традицией изучения неформальных практик. The article compares two approaches to the analysis of corruption: the global corruption paradigm - a downstream view on corruption promoted by international organisations and policy makers, the so-called outsiders, and the analysis of informal practices - an upstream, or bottom-up, perspective of insiders, which contextualises motives and meaning of corrupt practices. The global corruption paradigm rests on the premises that corruption can be defined, measured and controlled. Since the 1990s, data on corruption have been systematically collected and monitored, yet there has been little progress in combatting the phenomenon across the globe. Success cases are rare, and policy makers are increasingly dissatisfied with existing indicators and approaches to anti-corruption policies. On the one hand, the paper articulates the critique of assumptions, preconceptions and methodology implicit in the prevailing corruption paradigm. We question the cultural and historical neutrality of the definition of corruption, problems with its measurement, and implications for policy-making. On the other hand, the paper argues for the 'disaggregation' of the corruption paradigm and the necessity to integrate local knowledge and insiders' perspectives into corruption studies. The combination of the two approaches will provide for more effective ways of tackling the challenges of corruption, especially in endemically corrupt systems

Optical observations of "hot" novae returning to quiescence

We have monitored the return to quiescence of novae previously observed in outburst as supersoft X-ray sources, with optical photometry of the intermediate polar (IP) V4743 Sgr and candidate IP V2491 Cyg, and optical spectroscopy of these two and seven other systems. Our sample includes classical and recurrent novae, short period (few hours), intermediate period (1-2 days) and long period (symbiotic) binaries. The light curves of V4743 Sgr and V2491 Cyg present clear periodic modulations. For V4743 Sgr, the modulation occurs with the beat of the rotational and orbital periods. If the period measured for V2491 Cyg is also the beat of these two periods, the orbital one should be almost 17 hours. The recurrent nova T Pyx already shows fragmentation of the nebular shell less than 3 years after the outburst. While this nova still had strong [OIII] at this post-outburst epoch, these lines had already faded after 3 to 7 years in all the others. We did not find any difference in the ratio of equivalent widths of high ionization/excitation lines to that of the Hbeta line in novae with short and long orbital period, indicating that irradiation does not trigger high mass transfer rate from secondaries with small orbital separation. An important difference between the spectra of RS Oph and V3890 Sgr and those of many symbiotic persistent supersoft sources is the absence of forbidden coronal lines. With the X-rays turn-off, we interpret this as an indication that mass transfer in symbiotics recurrent novae is intermittent.Comment: In press in Monthly Notices of the Royal Astronomical Societ

Influence of the toxic effect of zinc and mineral starvation on the growth and development of buckwheat plantlets <i>in vitro</i>

Background. Common buckwheat is a cereal crop with high potential for genetic improvement in terms of developing breeding material resistant to abiotic stressors. To date, there have been no reports on in vitro production of buckwheat plantlets resistant to high doses of zinc and a lack of macronutrients.   Materials and methods. Aseptic single-node cuttings from the obtained regenerated plants of common buckwheat cultivars ‘Dikul’ and ‘Izumrud’ were cultivated in vitro on nutrient media with the addition of the selection factor ZnSO4 × 7 H2O in a concentration of 808–1313 mg/L. Survived plants were microcloned on nutrient media without macrosalts for mineral starvation modeling. Morphological traits and general nonspecific adaptation reactions of the plantlets were evaluated for the following characteristics: plant height, the number of internodes, the number of leaves, leaf blade length, the presence of roots, and leaf color.   Results. According to the results of the 33-day cultivation of test-tube microcuttings on media with zinc toxicity, 33–91 % of lines resistant to ionic stress were selected in different variants. The secondary testing of the plantlets under conditions of mineral starvation in vitro turned out to be the strongest inhibitory factor for buckwheat. At the same time, high resistance to stress was observed in cv. ‘Dikul’. Cultivation of the obtained buckwheat lines on the MS nutrient medium for two passages showed a sufficiently high level of regeneration in the studied genotypes. The test-tube buckwheat plantlets obtained under selective conditions are promising material for further breeding as well as for studying the possibility of their use as phytoremediators