482 research outputs found
Nonlinear twisted multicore fibers with PT-symmetry
No full textWe investigate linear and nonlinear modes of parity-time (PT)-symmetric multicore fibers with a twist of peripheral cores with gain and loss around
the lossless central core. We determine the spectral properties of such a light guiding system and demonstrate that the presence of the lossless central core combined with the fiber twist may significantly change the supermode structure, as well as the PT-symmetry breaking threshold of the multicore fiber with gain and loss. We also construct stationary nonlinear modes of the fiber and verify their stabilit
How to Stimulate Myocardial Regeneration in Adult Mammalian Heart: Existing Views and New Approaches
No full textStem cell-based therapy has been considered as a promising option in the treatment of ischemic heart disease. Although stem cell administration resulted in the temporary improvement of myocardial contractility in the majority of studies, the formation of new cardiomyocytes within the injured myocardium has not been conclusively demonstrated. Consequently, the focus of research in the field has since shifted to stem cell-derived paracrine factors, including cytokines, growth factors, mRNA, and miRNA. Notably, both mRNA and miRNA can enter into the extracellular space either in soluble form or packed into membrane vesicles. Stem cell-derived paracrine factors have been shown to suppress inflammation and apoptosis, stimulate angiogenesis, and amplify the proliferation and differentiation of resident cardiac stem cells (CSCs). Such features have led to exosomes being considered as potential drug candidates affording myocardial regeneration. The search for chemical signals capable of stimulating cardiomyogenesis is ongoing despite continuous debates regarding the ability of mature cardiomyocytes to divide or dedifferentiate, transdifferentiation of other cells into cardiomyocytes, and the ability of CSCs to differentiate into cardiomyocytes. Future research is aimed at identifying novel cell candidates capable of differentiating into cardiomyocytes. The observation that CSCs can undergo intracellular development with the formation of "cell-in-cell structure" and subsequent release of transitory amplifying cells with the capacity to differentiate into cardiomyocytes may provide clues for stimulating regenerative cardiomyogenesis.This work was supported by the grants from the Russian Foundation for Basic Research (Nos. 12-04-00941 and 16-04-01424) and Program of Presidium of Russian Academy of Sciences "Fundamental Sciences for Medicine" (2012-2014), by the state assignment of FASO of Russia ("The mechanisms of development of neuropsychic, metabolic, and hormonal dysfunctions in the nervous and endocrine diseases and the approaches for their correction"), and by the Government of Russian Federation, Grant 08-08.Belostotskaya, G (reprint author), Russian Acad Sci, Sechenov Inst Evolutionary Physiol & Biochem, Grp Cytoanalysis, St Petersburg, Russia; Almazov Natl Med Res Ctr, Inst Expt Med, St Petersburg, Russia.
[email protected]; [email protected]; [email protected]; [email protected]
Lobbies in the Making of American Foreign Policy in the South Caucdsus
No full textThe article analyzes the role of lobbies in decision-making in the U.S. toward the South Caucasus states. It also examines lobbying peculiarities of Armenia, Azerbaijan and Georgia as well as mechanisms of their influence over the Congress and American expert community. The author outlines a number of prime issues each Republic lobbies and how they refract U.S. interests in the region
Ethnocultural Factor of Inclusive Education Development (by the Examples of the Russian Federation and Kyrgyz Republic)
No full textThe article addresses the problems of inclusive education development through the prism of ethnocultural factors. A small comparative analysis of inclusive education development is given: legislative and law basis, cultural traditions in Russia and Kyrgyzstan, language and customs. The ethnocultural factor of inclusive education development is expressed through the language of “study” at schools and professional educational organizations. The author emphasizes the signs of our time – language assimilation in the countries of the former Soviet Union. It is shown that many parents in the north of Kyrgyzstan send their children, including children with disabilities, to study at Russian schools, and it causes additional barriers in learning, along with the barriers caused by physical and intellectual disabilities
GAMMA-400 space observatory
No full textA new important step in high-energy gamma-ray astronomy has been made with the beginning of Fermi LAT observations. But, as usual, a lot of new problems arise, in particular, the number of unidentified discrete gamma-ray sources is about 40%. To solve them it is necessary to improve the angular resolution up to 0.01°, the energy resolution up to 1%, and to extend the observable energy range to 3000 GeV. A new generation instrument, the GAMMA-400 gamma-ray telescope, will correspond to these requirements. The instrument will be also equipped with transition radiation detector and neutron detector to measure electron and positron fluxes more reliably. The GAMMA-400 launch is planned in 2016-2017
Genus <i>Nicotiana</i> L.: a review of traits significant for ornamental crop production
No full textBackground. The collection of Nicotiana L. species (Solanaceae) maintained at the All-Russian Scientific Research Institute of Tobacco, Makhorka and Tobacco Products (VNIITTI) is a valuable genetic resource used in breeding and genetic research on interspecific hybridization, cytoplasmic male sterility, and as a genebank for resistance to major tobacco diseases. Many species have ornamental features and properties: bright color and unusual morphology of the corolla, aroma, peculiar plant shape and others, and are promising for use in landscaping and garden designing. To identify and evaluate such species the collection was for the first time screened for a set of morphological and ornamental characters.Materials and methods. Thirty-seven accessions of Nicotiana spp. were studied in the greenhouses and at the experimental breeding site of VNIITTI using breeding methods and agricultural practices developed at the Institute and generally accepted in crop production.Results and conclusion. Phenotypic assessment of 37 Nicotiana accessions resulted in identifying for the first time 14 traits of ornamental value and selecting 18 original species and 10 hybrids of N. alata × N. × sanderae environmentally adapted to the local conditions and promising for landscaping and garden designing: with bright flowers, prolonged flowering, and relative resistance to stressful weather conditions. The typicality and stability of their progeny was assessed, and their germplasm was maintained and preserved in vivo
“The geopolitics of technology”: International relations and the fourth industrial revolution
No full textContemporary international relations as well as the life of an individual as we know it would
not be possible without the three Industrial revolutions. They have occurred in the course of the last three hundred years of human history and came to be part of a single continuous process
of changing technological waves. Each revolution defined how people would live, work,
and communicate with one another. Each industrial revolution set the dynamics for international
relations and created new political conflicts. The fourth industrial revolution that we are
going through today is also accompanied by geopolitical rivalry and develops exponentially,
not in a linear projection. It pierces through all layers of human activity and runs the risk of
changing the very nature of humans. The character of modern-day technology makes it hard
to perceive it through the lens of a mere consumer since technology impacts us as citizens and
deals with the three key concepts for people throughout their history: justice, freedom, and
power. The author hypothesizes that the three concepts are closely interlinked with the three
main megatrends of technology’s influence over politics respectively, — the call for a new
social contract, the problem of localization of big data and the associated pursuit of states for
digital sovereignty, and the development of artificial intelligence. Therefore, the present work
is an attempt to outline some key trajectories in how the new technological wave fractures the
three concepts and how all of this impacts international relations.The study was financially supported by MGIMO-University of the Ministry of Foreign Affairs of
Russia within the framework of the research project of the Institute for International Studies No. 2023-03-02
Treatment of covid-19 from the perspective of endotheliopathy correction and prevention of thrombotic complications. The agreed position of the experts
No full textThe proposed consensus position of the experts present approaches to the diagnosis, treatment and secondary prevention of throm-botic complications and endothelial dysfunction in COVID-19 for their use in outpatient visits. Experts confirmed the position of LMWH in hospitalized patients. Parnaparin sodium is the optimal choice for these patients, due to strong anti-inflammatory effect and a convenient dosing regimen. Experts confirmed endothelial damage as an important factor in the development of hyper-coagulation in outpatients with COVID-19. According to expert’s consensus position, sulodexide may be a pathogenetic approach for the problem of endothelial dysfunction, especially — for period of convalescence. Experts recommend to introduce of sulo-dexide into the Temporary methodological recommendations of the Ministry of Health of the Russian Federation: for outpatients with light forms COVID-19, for patients with high risk of bleeding, also — for patients at the stage of rehabilitation to prevent recurrent VTE and reduce the risk of developing pulmonary fibrosis
- …
