The preventive destruction of a hazardous asteroid

One means of countering a hazardous asteroid is discussed: destruction of the object using a nuclear charge. Explosion of such an asteroid shortly before its predicted collision would have catastrophic consequences, with numerous highly radioactive fragments falling onto the Earth. The possibility of exploding the asteroid several years before its impact is also considered. Such an approach is made feasible because the vast majority of hazardous objects pass by the Earth several times before colliding with it. Computations show that, in the 10 years following the explosion, only a negligible number of fragments fall onto the Earth, whose radioactivity has substantially reduced during this time. In most cases, none of these fragments collides with the Earth. Thus, this proposed method for eliminating a threat from space is reasonable in at least two cases: when it is not possible to undergo a soft removal of the object from the collisional path, and to destroy objects that are continually returning to near-Earth space and require multiple removals from hazardous orbits

ASSESSMENT OF REFRACTORY GOLD-BEARING ORES BASED OF INTERPRETATION OF THERMAL ANALYSIS DATA

The article presents the results of a study on the possibility to assess refractory gold-bearing ores using thermal analysis data. It studies the flotation concentrates obtained during the enrichment of double refractory sulfide gold-bearing ores. This type of ore is complicated by the fine impregnation of gold in sulphide minerals and the presence of sorption-active scattered carbonaceous matter, which is in close association with sulphides. The results of thermogravimetric and mass spectrometric studies of refractory gold-bearing ores are presented. The obtained fragments for kerogen CH (m/z = 15), C2H (m/z = 29) and C3H (m/z = 43) indicate the presence of various types of carbonaceous matter in the studied samples. It is justified that the degree of sorption activity of carbonaceous matter depends on the presence of kerogen and bitumen in the ore. High sorption activity of scattered carbonaceous material significantly affects the processing technology of ores and concentrates, both flotation and pyro- and hydrometallurgical methods. Thermogravimetric and mass spectroscopic analyzes can be used to determine the degree of preg-robbing of refractory gold-bearing ores. The obtained results predetermine the direction of creating new methods and technologies in the field of decarburization of refractory gold-bearing ores in the integrated development of solid minerals in the mining regions of Russia

New advances in Raman study of polyvinylchloride structure

In this work we investigated Raman spectra of a number of industrial grades of polyvinylchloride powder and films, prepared from solutions in tetrahydrofuran and acetophenone. The number and spectral characteristics of the Raman lines in the spectral regions of the C-Cl stretching vibrations and in the region of the C-H and CH2 stretching vibrations were evaluated

DINAMICA PIEȚEI FORȚEI DE MUNCĂ ÎN BULGARIA

BACKGROUND. Bulgaria, as many countries in the world is experiencing a critical period for the health workforce. The shortage of qualified nurses is one of the biggest obstacles for improving the health-system performance. Lack of strategic planning based on profound market research and elaboration of scientifically based prognosis further deteriorate the current nursing labor market disequilibrium. THE AIM of the study is to explore the main factors influencing the nursing market disequilibrium in Bulgaria and to make an evidence-based forecast of the future needs for nurses in order to suggest relevant workforce development strategies. MATERIAL AND METHODS. The study employs a combination of sociological and statistical methods. The analysis is based on the official statistical data on Bulgarian nursing personnel up to 2012. Primary information is collected through self-administered questionnaires distributed among 337 practicing nurses from April 2007 to December 2012. Data are processed with the packages MS Office Excel 2010 and SPSS v. 13. RESULTS. Results indicate that a decrease in the demand for nursing labour caused large staff layoffs during the first stage of the restructuring period (1990-2000) followed by a severe drop in the number of nurses due to emigration and exodus from the profession. There are also educational and qualification problems along with unattractiveness of the nursing practice due to high workload and low remuneration. With the mean age of 49 severe nursing workforce’s deficit is expected in 10-15 years due to retirement. According to our estimations the deficit of nurses will account for 3162 specialists by 2030. CONCLUSION. The Bulgarian nursing labor market disequilibrium is due to long-term structural imbalances. As the market mechanism is unable to attain equilibrium Bulgarian government should be urgently involved in workforce planning and initiate actions and strategies for producing and retaining the highly qualified nurse professionals in Bulgaria.   Key words: nursing workforce market, Bulgaria, disequilibrium, factors.  CONTEXT. Similar multor state, Bulgaria traversează, de asemenea, o perioadă critică în ceea ce privește piața forței de muncă din sănătate. Lipsa de asistente medicale calificate este unul dintre cele mai mari obstacole pentru îmbunătățirea performanței sistemului de sănătate. Lipsa planificării strategice bazată pe cercetare amănunțită a pieței și lipsa prognozelor și proiecțiilor bazate pe argumente științifice conduc la dezechilibrul existent pe piața muncii asistentelor medicale, existent la momentul actual. SCOPUL studiului este de a explora factorii principali care influențează dezechilibrul de pe piața muncii asistentelor medicale în Bulgaria și de a face prognoze, bazate pe dovezi, ale nevoilor viitoare de asistente medicale, în scopul de a sugera strategii viitoare de dezvoltare a forței de muncă. MATERIAL ȘI METODE. Studiul  de față abordează o combinație de metode sociologice și statistice.  Analiza are la bază date statistice oficiale privind personalul medical din Bulgaria, date disponibile inclusiv pentru anul 2012. Informatiile primare au fost colectate cu ajutorul unor chestionare auto-administrate, distribuite unui număr de 337 asistente medicale practicante, în perioada aprilie 2007 - decembrie 2012. Datele sunt prelucrate cu pachetele de analiză MS Office Excel 2010 și SPSS v. 13. REZULTATE. Rezultatele indică faptul că scăderea cererii pentru asistentele medicale a cauzat  disponibilizările masive din timpul primei etape a perioadei de restructurare 1990-2000, urmată de o scădere severă a numărului de asistente medicale din cauza emigrării și exodul profesional. Există probleme educațiomale și de calificare, alături de lipsa de atractivitate a practicii de asistentă medicală din cauza volumului mare de muncă și a nivelului redus de salarizare. Cu o medie crescută a vârstei asistentelor medicale, de 49 de ani,  un deficit sever este așteptat în următorii 10+15 ani, din cauza fenomenului de pensionare. Conform estimărilor noastre, deficitul de asistente medicale, până în anul 2030, va fi de 3162 de specialiști. CONCLUZII. Dezechilibrul numeric de asistente medicale de pe piața forței de muncă din sănătate este cauza unor dezechilibre structurale pe termen lung. Cum mecanismul piaței nu este în măsură să rezolve acest dezechilibru, guvernul din Bulgaria va trebui urgent să  se implice în planificarea forței de muncă și să inițieze acțiuni și strategii de creare și menținere a asistentelor medicale calificate, în Bulgaria.  Cuvinte cheie: piața forței de muncă, asistente medicale, dezechilibru, factori frenatori, Bulgaria &nbsp

SPECIES DIVERSITY OF THE VIR COLLECTION OF GRAIN LEGUME GENETIC RESOURCES AND ITS USE IN DOMESTIC BREEDING

The world’s genebanks hold 7.5 million germplasm accessions of plant genetic resources (PGR). One of the qualitative characteristics of the PGR collections is the species diversity, in particular, the presence of crop wild relatives (CWR), which makes it possible to widen the use of gene pools in the breeding process. The collection of the Vavilov Institute (VIR) is one of the most diverse holdings in the number of plant species. A survey is provided here of the species diversity in VIR’s grain legume collection, and its use in domestic breeding practice is analyzed. Comparison of this diversity with the state of PGR exploitation in the world makes it possible to assess the prospects of more efficient utilization of gene pool potential, especially for species that are unjustifiably cultivated on a too small scale or even neglected as crops in this country. The VIR collection of grain legumes incorporates 196 species from 9 genera of the family Fabaceae. This number includes cultigens and CWR. The cultivars of 21 species of grain legumes listed in the State Register of Breeding Achievements (2018) are adapted to the soil and climate conditions of this country. However, the species diversity of the collection could be used more efficiently in domestic plant breeding and crop production. This concerns both underutilized crops in Russia (broad beans, lima beans and grass pea) and those whose adaptive potential is adjusted only to certain and limited areas of the Russian Federation (Tepary beans and Vigna spp.). It is also necessary to exploit more efficiently species of the wild flora, both for direct utilization as pastures, green manure or phytoremediation crops and for introgressive breeding and domestication (Vicia benghalensis L., V. narbonensis L., Lathyrus sylvestris L., Lupinus hartwegii Lindl., etc.). Incorporation of crop wild relatives into the breeding process is promising for crop improvement in a number of aspects: for example, to increase resistance to diseases, pests, abiotic stressors, etc

Multi-spin strings on AdS(5)xT(1,1) and operators of N=1 superconformal theory

We study rotating strings with multiple spins in the background of $AdS_5\times T^{1,1}$, which is dual to a $\mathcal{N}=1$ superconformal field theory with global symmetry $SU(2)\times SU(2)\times U(1)$ via the AdS/CFT correspondence. We analyse the limiting behaviour of macroscopic strings and discuss the identification of the dual operators and how their anomalous dimensions should behave as the global charges vary. A class of string solutions we find are dual to operators in SU(2) subsector, and our result implies that the one-loop planar dilatation operator restricted to the SU(2) subsector should be equivalent to the hamiltonian of the integrable Heisenberg spin chain.Comment: 8 pages, revtex4, twocolum

CLINICODIAGNOSTIC VALUE OF DETERMINATION OF LEPTIN AND ANDROGENIC HORMONES IN BOYS AND TEENAGERS WITH OBESITY

Purpose: To address the relation between the levels of androgenic hormones and metabolic indices in obese male children and adolescents.Materials and methods: 175 boys were examined, of which children at the age of 11-12 – 75 persons, teenagers at the age of 13-15 – 100 persons. Obesity degree according to Knyazev and sexual development stage according to Tanner were evaluated, the following hormones were identified in the blood serum: luteinizing hormone, follicle-stimulating hormone, testosterone, dihydrotestosterone, androstenedione, anti-Müllerian hormone and inhibin B as well as insulin, leptin and lipometabolism rates.Results: In the group of 13-15-year-old boys 20% of boys with obesity had the 1st-2nd stage of sexual development according to Tanner. In children with obesity in the prepubescent age the following was detected: dyslipidaemia, hyperleptinemia and high level of AMH; there are no reliable differences in the level of sex hormones if compared to children with normal weight. 13-15-year-old boys with the 1st-2nd stage of sexual development according to Tanner have the highest leptin rates (among all groups), AMH (in comparison to the same age) and very low rates of sex hormones.Summary: Hyperleptinemia detected at the stage of prepubescent age is an important physiological regulator of a signal to the beginning of pubescence. The heightened level of leptin in boys with obesity in pubescence age as well as the maintained heightened concentration of AMH suppressing the increase of the androgenic hormone level causes the development of prolonged pubescence

Numerical Model of the Motion of Artificial Earth Satellite Systems. Latest Version

В работе представлено описание последней версии численной модели движения систем искусственных спутников Земли (ИСЗ), разработанной в НИИ ПММ ТГУ. Представленное программное математическое обеспечение (ПМО) позволяет прогнозировать движение ИСЗ, исследовать хаотичность движения околоземных объектов, вычислять резонансные характеристики для изучения влияния вековых резонансов на динамику ИСЗ. Программный комплекс реализован в двух версиях: для персонального компьютера (ПК) и в среде параллельных вычислений «СКИФ Cyberia» ТГУ. Для удобства ПМО дополнено пользовательским интерфейсом.The paper presents a description of the latest version of the numerical model of the motion of artificial Earth satellites (AES) systems developed at the Research Institute of Applied Mathematics and Mechanics of Tomsk State University. The presented mathematical software (MO) makes it possible to predict the motion of the satellite, to investigate the chaotic character of the motion of AES, to calculate resonant characteristics to study the influence of secular resonances on the dynamics of the satellite. The software package is realized in two versions: for a personal computer and in the environment of parallel computing “SKIF Cyberia” TSU. For convenience, the MO is supplemented with a user interface.Исследование выполнено за счет гранта Российского научного фонда № 19-72-10022, https://rscf.ru/project/19-72-10022/

Semiclassical Strings, Dipole Deformations of N=1 SYM and Decoupling of KK Modes

In this paper we investigate the recently found $\gamma$-deformed Maldacena-Nunez background by studying the behavior of different semiclassical string configurations. This background is conjectured to be dual to dipole deformations of $\N=1$ SYM. We compare our results to those in the pure Maldacena-Nunez background and show that the energies of our string configurations are higher than in the undeformed background. Thinking in the lines of (hep-th/0505100) we argue that this is an evidence for better decoupling of the Kaluza-Klein modes from the pure SYM theory excitations. Moreover we are able to find a limit of the background in which the string energy is independent of $\gamma$, these strings are interpreted as corresponding to pure gauge theory effects.Comment: 31 pages, references added, new solutions in Section 7 presented, an appendix added, to appear in JHE

Numerical Models of Motion of Artificial Satellites of the Earth and the Moon. Latest Version

A description of the latest versions of the numerical models of the motion of artificial satellites of the Earth (AES) and the Moon (AMS) developed at the RIAMM NRTSU is presented and the possibilities of their use in solving problems of satellite dynamics are descussed.Представлено описание последних версий разработанных в НИПММ НИТГУ численных моделей движения искусственных спутников Земли (ИСЗ) и Луны (ИСЛ) и показаны возможности их использования в решении задач спутниковой динамики.Работа выполнена при финансовой поддержке РНФ в рамках научного проекта № 19-72-10022 от 07.08.2019