Odessa Astronomical Publications最新文献

{"title":"ASTEROID POSITIONS BASED ON THE DUSHANBE PART OF THE FON PROJECT OBSERVATIONS","authors":"S. Shatokhina, H. Relke, A. Mullo-Abdolov, O. Yizhakevych, Q. Yuldoshev, Y. Protsyuk, V. Andruk","doi":"10.18524/1810-4215.2020.33.216421","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216421","url":null,"abstract":"Asteroid images identification and creation the positional catalogs based on digitized photographic observations of previous years were continued. Namely, the cooperation between Ukrainian Virtual Observatory (UkrVO) and the Institute of Astrophysics of the Academy of Sciences of Tajikistan make it possible to expand this work by involving numerous additional archives of digitized observations and processing services and thus obtaining new original data about the Universe. The Dushanbe part of the Northern Sky Survey (FON project) is represented by about 1570 photographic plates obtained in 1985-1992 on the Zeiss-400 astrograph at the Hissar Astronomical Observatory of the Institute of Astrophysics of the Academy of Sciences of Tajikistan. At present, their digitization and further scan processing continue until the final product is obtained in the form of a catalog of equatorial coordinates and stellar magnitudes for all registered objects on the plates. The equatorial coordinates α, δ of all objects on the plates were obtained in the Tycho-2 reference system at the epoch of exposure of each plate. Photometry of stars for the plates was carried out based on the principles implemented in the processing of the plates of the FON project using photoelectric measurements of stars to construct the characteristic curves of the plates. Photographic B-magnitudes of objects were calibrated with photoelectric standards. In parallel with solving the main task of the project to create a catalog of stars and galaxies, we analyzed the results of processing the plates to search for images of asteroids and comets and create a catalog of their coordinates and values. About 300 positions of asteroids and comets were obtained with visual magnitudes from 7 to 16.5. All positions of the asteroids were compared with the ephemeris. A preliminary analysis of the O-C differences and their comparison with similar results obtained from the digitized observations of the Kyiv and Kitab parts of the FON project are conducted.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42831443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANOMALOUS WIDENING OF 5434.5 LINE IN SUNSPOTS: SUPER-STRONG MAGNETIC FIELDS?","authors":"V. Lozitsky, S. Osipov, M. Stodilka","doi":"10.18524/1810-4215.2020.33.216451","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216451","url":null,"abstract":"We present results of spectralobservations of two sunspots in six metal lines near Fe I5434.5 A, which have effective Lande factors g eff from –0.014 to 2.14. The observations were made on July 8 andAugust 25, 2015, with the ATsU-5 telescope of GAO NASof Ukraine using a circular polarization analyzer andspectra registration with the SBIG ST-8300 CCD camera.The following line parameters are compared: observedsplitting of I ± V profiles, the width and depth of the StokesI profiles. Significant differences of the measured magneticfield strengths B eff were found in separate places of thespots and by lines with different g eff values. The Fe I 5434.5Ǻ line (g eff = –0.014) shows measurable splitting in somelocations of the sunspots, which corresponds to themagnetic field B obs ≈ 20 kG. Comparison of the widths anddepths of the line profiles revealed several special places inthe sunspots, where the Fe I 5434.5 Ǻ line was expandedadditionally by ≈ 15–35%, whereas other lines with largerLande factors did not have such a feature. One of thereasons for this expansion could be a sharp and localincrease of turbulent velocities, but no active processes suchas solar flares or significant Doppler flows were observed atthese locations. A semi-empirical model constructed for thefirst sunspot by FeI 5434.5 line using inverse code withTikhonov`s stabilizers shows an anomalous feature – themaximum of microturbulent velocities in the upperphotosphere and the temperature minimum zone instead ofthe usual small increase of microturbulence at these heights.This may be the effect of very strong magnetic fields ofmixed polarity or unresolved turbulent structures. As to firstcase, the estimated value of the magnetic field in suchlocations of sunspots is ~10 5 G, which requires additionalcareful verification.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46621742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE ROLE OF MACROSCOPIC TURBULENT DIAMAGNETISM IN ENSURING LONG-TERM STABILITY OF SUNSPOTS","authors":"V. Krivodubskij","doi":"10.18524/1810-4215.2020.33.216449","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216449","url":null,"abstract":"We investigated the role of macroscopic turbulent diamagnetism in ensuring the long-term stability of the equilibrium state of the sunspots. The physical meaning of macroscopic diamagnetism of turbulent plasma is expulsion of a large-scale magnetic field from areas with increased turbulence intensity to areas with reduced turbulence. We follow the idea of Krause & Rüdiger (1975) that a strong magnetic field of a sunspot modifies the structure of turbulence in spot umbra, so it becomes two-dimensional. In addition, we take into account the strong magnetic suppression of turbulence in the spot, where it becomes less intense than the turbulent convection around the spot. As a result, a relatively thin transitional vertical layer of permeable convection (convective overshot layer) should be formed between these sections, in which the intensity of turbulent pulsations decreases noticeably in the transverse direction during the transition from the convection section to the spot. In this permeable convection layer, the effect of turbulent diamagnetic displacement of the magnetic field from the convection region to the sunspot occurs. Owing to the two-dimensional turbulent diffusion, the magnetic field of the spot spreads outwards, while the intense turbulent pulsations in the convection region return the magnetic field in the opposite direction, back to the spot. Therefore, these two oppositely directed processes of magnetic field transfer in the horizontal plane compete with each other. As a result, the magnetic fields that are transferred due to turbulent diffusion outward from the sunspot will be thrown backward into the spot due to strong external turbulent convection. In our opinion, this effect should ensure long-term stability of the equilibrium state of the magnetic field of sunspots and support them in the form of isolated vertical unipolar magnetic force tubes.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41476353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SPECIFIC FEATURES OF STRUCTURES IN THE INNER COMA OF COMET C/2017 T2 (PANSTARRS) AS OBSERVED WITH THE OMT-800 TELESCOPE OF THE ODESSA OBSERVATORY TELESCOPE NETWORK","authors":"V. V. Kleshchenok, S. Kashuba, S. Andrievsky, Y. Gorbanev","doi":"10.18524/1810-4215.2020.33.216432","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216432","url":null,"abstract":"Observations of the comet werecarried out using the OMT-800 telescope (the primarymirror diameter D = 80 cm; the focal length F =214 cm) of the Odessa Observatory telescope networkfrom January to June 2020. Image processing was per-formed through standard methods using subtraction ofdark and flat field frames. The resulting frames wereemployed to analyse the morphology of the cometaryinner coma using digital filters. Isophotes of the comaand images of its structures appearing as fans and jetswere obtained. The presence of a strong fan, whichdistorts the coma’s standard appearance and makesit elongated perpendicularly to the Sun-comet line, isobserved over the period from January to April. Lateron, a weak jet that hardly affects the coma’s standardshape appears to replace the fan. The jet reaches itspeak intensity near perihelion and then gets fainterrapidly. Such behaviour of the coma structures isindicative of the presence of two active areas on thecometary nucleus surface, for which the matter outflowis governed by the Sun illumination conditions. Oneof these areas, being more active, is responsible for theappearance of a strong fan. The other area, which isfar less active, generates a jet that manifests itself nearperihelion. The peak dust production of the comet120–150 days before perihelion is due to the presenceof an active fan in the inner coma.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45176946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FEATURES OF THE DEVELOPMENT OF A CIRCULAR SOLAR FLARE","authors":"S. N. Chornogor, N. Kondrashova","doi":"10.18524/1810-4215.2020.33.216444","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216444","url":null,"abstract":"We present the results of the analysis of morphology and evolution of the circular solar flare using H-alpha images. H-alpha filtergrams were obtained with the Meudon spectroheliograph. The active region NOAA 9087 had a complex multipolar magnetic field configuration. New magnetic fluxes emerged during the evolution of this flare-productive active region. The high flare and surge activity was observed in the active region. According to Solar Geophysical Data (SGD) the 3N/M6.4 class solar flare occurred on July 19, 2000 at 06:37 UT, peaked at 07:23 UT and lasted 2.5 hours. Two bright kernels appeared near large positive-polarity sunspot at the beginning of the flare. In a few minutes bright kernels occurred in the center of the active region near polarity inversion line. Space solar observatory Yohkoh detected a hard X-ray (HXR) coronal source in the 13.9-22.7 keV and 22.7-32.7 keV energy bands in this location. New kernels appeared in the southern and eastern parts of the active region at the boundaries of the chromospheric network. They brightened sequentially clockwise, which may indicate a slipping reconnection. Magnetic reconnection was observed in the main phase of the flare in the eastern part of the active region. In the late flare phase arcade of post-reconnection EUV loops connected the main flare ribbon with the place of repeated reconnection. Additional heating may be required for the explanation of the long flare decay phase. Flare ribbons of the circular shape were formed. The complex magnetic configuration of the studied active region and circular shape of the ribbons suggest that it had a fan-spine magnetic topology with null points. Possibly, flare ribbons are the locations of intersections of the fan quasi-separatrix layer with the chromosphere. They appeared as a result of heating or particle beam moving along a quasi-separatrix layer from a source in the corona.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42224877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RELATIONSHIP OF SCR, CME AND CORONAL SHOCK WAVES WITH THE PARAMETERS OF TYPE IV AND II SOLAR RADIO BURSTS","authors":"E. A. Isaeva","doi":"10.18524/1810-4215.2020.33.216446","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216446","url":null,"abstract":"ABSTRACT. This paper presents the results of a comparative analysis of the relationship between solar cosmic rays (SCR), coronal mass ejections (CME), and coronal shock waves (CSW) with the parameters of solar continual type IV radio bursts, as well as with the parame- ters of type II radio bursts. The sample under study con- tains 147 proton events accompanied by type IV continu- um radio bursts in the 25-15400 MHz range, type II radio bursts in the 25-180 MHz range, as well as CME and cor- onal shock waves. For the analysis, we used original rec- ords of solar radio emission at 8 fixed frequencies in the range 245-15400 MHz according to data from RSTN (Ra- dio Solar Telescope Network), original records of dynam- ic spectra from SRS (Solar Radio Spectrograph) in the range of 25-180 MHz, as well as original records intensity of the flux of SCR protons with proton energies in the range> 1-100 MeV according to data from the GOES spacecraft. A comparative analysis showed that the rela- tionship between the intensity of the SCR proton flux and the CME velocity is, on average, much stronger with the parameters of type IV radio bursts than with the parame- ters of type II radio bursts, which indicates the dominant role of the SCR acceleration process in the flare region, rather than shock waves. However, detailed studies of the fine structure of type II radio bursts have shown that there is a fairly strong relationship between the intensity of the flux of mean-relativistic protons I p and the frequency f min,1 at the fundamental harmonic (at the 1-st harmonic) at the time t min corresponding to the minimum relative distance b min between the harmonics of type II radio bursts. De- tailed studies of the fine structure of type II radio bursts have also shown that there is a strong relationship between the intensity of the SCR proton flux I p and parameter V II , which characterizes the displacement of the shock front with time t i in a narrow frequency range of 25-60 MHz.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45439143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GROUPS OF METEORITE-PRODUCING METEOROIDS AND METEORITES IN ASTEROIDAL ORBITS AND THEIR SOURCES","authors":"Y. Gorbanev, N. Konovalova, N. K. Davruqov","doi":"10.18524/1810-4215.2020.33.216430","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216430","url":null,"abstract":"This paper presents the results of the analysis of possible existence of nine near-Earth meteorite-producing groups in asteroidal orbits, consisting of sporadic fireballs from the IAU MDC 2007 database, sporadic meteors from the SonotaCo database, meteorites – namely, L5, L6 and H4-H6 ordinary chondrites and an ureilite, for which atmospheric and orbital parameters are known from instrumental observations – and their plausible parent bodies, that is, near-Earth asteroids (NEAs). Orbits of the selected members of meteoriteproducing groups were classified as asteroidal according to the Tisserand parameter TJ > 3.1. In order to test the link between meteorite-producing groups in asteroidal orbits and their plausible parent bodies, we carried out an investigation into the possible existence of some known NEAs that move in similar orbits. Based on the orbital similarity, determined using the Drummond (DD) and Southworth & Hawkins (DSH) orbital similarity criteria, some associations between the identified NEAs, known meteorites in asteroidal orbits and small, as well as meteorite-dropping, meteoroids have been suggested. As a result, several meteorite-dropping sporadic fireballs and small meteors, whose orbits are currently similar to the orbits of known meteorites, have been detected and reckoned as possible members of the groups in asteroidal orbits; their plausible source regions have also been considered.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47043437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DISTRIBUTION OF THE OCCURRENCE OF THE INTENSIVE IONOSPHERE SCINTILLATIONS ON THE OBSERVATIONS OF THE COSMIC RADIO SOURCES AT THE DECAMETER WAVE RANGE","authors":"O. A. Lytvynenko, S. Panishko","doi":"10.18524/1810-4215.2020.33.216305","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216305","url":null,"abstract":". Effect of scintillations arises in the result of interaction of radio signal from the cosmic radio source with irregularities of ionosphere plasma which appears at the registration of observations as amplitude fluctuations. Wherein fluctuations of the different intensities and with the different long time periods can be observed. Scintillations of large intensity and with large characteristic times (periods) take an interest because its influence on records of the radio sources is very essential and can distort the record shape. In this case there is a need to consider the presence of the intensive fluctuations. In this sense it might be useful to investigate the frequency of occurrence of the intensive scintillation. Processing of the radio sources records was carried out on the observations of power cosmic radio sources at the passage through direction pattern of the radio telescope URAN-4 at frequencies 20 and 25 MHz during 1998-2007. Record's characteristics were obtained including ionosphere scintillation parameters. Also records with scintillations of large intensity and with long periods were marked. In this work daily distribution of intensive scintillations was analyzed. It was showed that occurrence of intensive scintillations changes in limits of 4-26% and it is larger on the lower frequency. Dependence of occurrence of scintillations from angle between direction on the radio source and line of geomagnetic field in the observation place was found. It was obtained that the maximum of the occurrence of the intensive scintillations for all observed radio sources appears on the nighttime of the day. Also local maximums of frequency of occurrence are exist which may be associated with the moments of sunrise and sunset.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47774157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE HOT DARK MATTER MODEL: FURTHER INVESTIGATION","authors":"D. Khokhlov","doi":"10.18524/1810-4215.2020.33.216299","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216299","url":null,"abstract":". In a recent paper, the model of the galaxy with hot dark matter was considered. The galaxy is divided into the inner region with the dominant baryonic matter (the elliptic orbit of the test particle) and the outer region with the dominant hot dark matter (the parabolic orbit of the test particle). It was assumed that the hot dark matter consists of hypothetical Planck neutrinos arising in the decay of the protons at the Planck scale. Galaxies formed from the baryonic matter, and the hot dark matter appears in the galaxies later. The rotation curves of the galaxies were studied in the model, including Milky Way, M33, NGC 2366 and IC 2574. In the present paper, the hot dark matter model is further investigated, with the application to M31, the system of M31 and the Milky Way, the globular clusters NGC 2419 and MGC1, the dwarf spheroidal galaxy Sculptor, ultra-massive quiescent galaxies from the COSMOS and UDS fields. The baryonic matter mass of M31 was estimated from the rotation curves, with the average value 1 . 6 × 10 11 m (cid:12) . The gravitational interaction of the Milky Way and M31 is considered. In the hot dark matter model, the dynamical masses of the Milky Way and M31 are twice their baryonic matter masses that gives the radial velocity of M31 toward the Milky Way, 106 km s − 1 . The hot dark matter mass in the globular clusters NGC 2419 and MGC1 is estimated. The value is small compared to the stellar mass in both the clusters. The hot dark matter mass within the half-light radius of the dwarf spheroidal galaxy 0 . 5 × 10 6 m (cid:12) . of stellar hot dark matter mass the half-light radius mass within half-light radius the of the hot dark matter and some perturbations flattens the velocity profile of the metal poor stars which is unsuitable to derive the dynamical mass. The evolution of ultra-massive quiescent galaxies from the COSMOS and UDS fields is considered. The dynamical to stellar mass relation is doubling during the evolution from z = 2 to 0 that can be explained by the absence of dark matter at z = 2 and the presence of the hot dark matter at z = 0 .","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48521538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TO THE PERSONALITIES OF THE UKRAINIAN ASTRONOMY: SCIENTIFIC WORK OF KOSTYANTYN SAVCHENKO","authors":"M. Balyshev, I. Vavilova","doi":"10.18524/1810-4215.2020.33.216290","DOIUrl":"https://doi.org/10.18524/1810-4215.2020.33.216290","url":null,"abstract":"The research is devoted to the study of the life and work of the outstanding Ukrainian astronomer-theoretician Kostyantyn Savchenko (1910–1956), who worked in the field of celestial mechanics and dynamic cosmogony at the Kharkiv and Odesa astronomical observatories in 1930–1950 years. As a result of historio-graphic analysis, we found that till now there is no comprehensive study of his scientific biography besides several publications related to certain facts of his life and activity, mostly in the Odesa period, including the reminiscences by Prof. V.K.Abalakin. Despite this, the vast majority of aspects of the scientist’s life, including his scientific and teaching activity in the Kharkiv period in 1930s, remains unexplored. The astronomer's scientific work was devoted to the study of the motion and rotation of celestial bodies with variable masses, the exploration of the perturbations of the planets by geometry methods, research of the physical nature of gravity, and the development of cosmogonic theories. We consistently describe the life and activity of Prof. K.N.Savchenko at the Kharkiv and Odesa astronomical observatories, the scientific and teaching work at the Kharkiv State University, the Kherson State Pedagogical Institute, and the Odesa State University, analyzing the archive documents and his scientific publications.","PeriodicalId":34039,"journal":{"name":"Odessa Astronomical Publications","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43262019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}