Astronomy & Astrophysics最新文献

{"title":"The fate of the interstellar medium in early-type galaxies. IV. The impact of stellar feedback, mergers, and black holes on the cold interstellar medium in simulated galaxies.","authors":"J. Nadolny, J. Michał Michałowski, M. Parente, Jens Hjorth, C. Gall, A. Leśniewska, M. Solar, Przemysław Nowaczyk, O. Ryzhov","doi":"10.1051/0004-6361/202449839","DOIUrl":"https://doi.org/10.1051/0004-6361/202449839","url":null,"abstract":"Removing the cold interstellar\u0000medium (ISM) from a galaxy is essential to quenching star formation, however,\u0000the exact mechanism behind this process remains unclear. The objective of this work is to find the mechanism responsible for dust\u0000and gas removal in simulated early-type galaxies. We studied a statistically significant sample of massive ( simulated early-type galaxies in a redshift range of 0.02--0.32 in the context of its ISM properties. In particular, we investigated the cold dust and gas removal timescales, the cold gas inflows, and their relation with black hole mass. We also investigated the evolution of galaxies in the dust mass and star formation rate (SFR) plane and the influence of merger events. Finally, we broke\u0000down the dust destruction mechanisms to find which (if any) of the implemented\u0000processes dominate as a function of a galaxy's stellar age. We find a good agreement with previous observational works dealing with\u0000the timescales of dust and removal from early-type galaxies. When considering the dust-to-stellar-mass ratio as a function of time in simulations, we recovered a similar decline as in the observational sample as a function of stellar age, validating its use for timing the ISM decline. Moreover, we recovered the observed relation between dust mass and the SFR for actively star-forming galaxies, as well as that of passive early-type galaxies. We also show that starburst galaxies form their own sequence on the dust mass and SFR plot in the form of $ dust, SB SFR ) + 6.533,$\u0000with a $2 scatter of 0.32. Finally, we find that type II supernova reverse shocks dominate the dust destruction at the early stages of early-type galaxy evolution; however, we also see that at later times, stellar feedback becomes more important. We show that merger events lead to morphological transformations by increasing the bulge-to-total stellar mass ratio followed by an increase in black hole masses. The black hole feedback resulting from radio mode accretion prevents the hot halo gas from cooling, indirectly leading to a decrease in the SFR.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"15 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141715759","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":"Investigation of the rotational spectrum of CH$_3$17OH and its tentative detection \u0000 toward Sagittarius B2(N)","authors":"Holger S. P. Muller, V. Ilyushin, Arnaud Belloche, F. Lewen, S. Schlemmer","doi":"10.1051/0004-6361/202451011","DOIUrl":"https://doi.org/10.1051/0004-6361/202451011","url":null,"abstract":"Methanol is an abundant and widespread molecule in the interstellar medium. The column \u0000 density of its 18O isotopolog, CH$_3$18OH, is in some star-forming regions so high \u0000 that the search for CH$_3$17OH is promising. But only very few transition frequencies \u0000 of CH$_3$17OH with a microwave accuracy have been published prior to our investigation. We want to extend the very limited rotational line list of CH$_3$17OH to be able \u0000 to search for this isotopolog in the interstellar medium. We recorded the rotational spectrum of CH$_3$17OH between 38 and 1095 GHz employing a \u0000 methanol sample enriched in 17O to 20. A torsion-rotation Hamiltonian model based on \u0000 the rho-axis method was employed to fit the data, as in our previous studies. \u0000 We searched for rotational transitions of CH$_3$17OH in the imaging spectral line survey \u0000 ReMoCA obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward the \u0000 high-mass star-forming region Sgr B2(N). The observed spectra were modeled under the assumption \u0000 of local thermodynamic equilibrium (LTE). The assignments cover $0 J 45$, $K_a 16$, and mainly the $ t = 0$ and 1 \u0000 torsional states. The Hamiltonian model describes our data well. The model was applied to derive \u0000 a line list for radio-astronomical observations. \u0000 We report a tentative detection of CH$_3$17OH along with secure detections of the more \u0000 abundant isotopologs of methanol toward Sgr B2(N2b). The derived column densities yield \u0000 isotopic ratios 12C/13C = 25, 16O/18O = 240, and 18O/17O = 3.3, \u0000 which are consistent with values found earlier for other molecules in Sgr B2. The agreement between the 18O/17O isotopic ratio that we obtained for methanol \u0000 and the 18O/17O ratios reported in the past for other molecules in Sgr B2(N) \u0000 strongly supports our tentative interstellar identification of CH$_3$17OH. \u0000 The accuracy of the derived line list is sufficient for further radio astronomical \u0000 searches for this methanol isotopolog toward other star-forming regions.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"32 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141715890","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 radio properties of z>3.5 quasars: Are most high-redshift radio-loud active galactic nuclei obscured?","authors":"A. C. U. D. Torino, Pino Torinese, Italy","doi":"10.1051/0004-6361/202449676","DOIUrl":"https://doi.org/10.1051/0004-6361/202449676","url":null,"abstract":"We explore the radio properties of powerful (rest-frame\u0000 luminosity $ at 500 MHz) high-redshift ($z 3.5$) quasars. The aim of this study is to gain a better understanding of radio-loud sources at the epoch when they reach the highest space density. We selected 29 radio-loud quasars at low radio frequencies (76 MHz). Their radio spectra, covering the range from 76 MHz to 5 GHz, are generally well reproduced by a single power law. We created samples that were matched in radio luminosity at lower redshift (from $z to $z to investigate any spectral evolution. We find that the fraction of flat-spectrum radio quasars (FSRQs) strongly increases with redshift (from $ 8$ at z=1.2 to $ 45$ at z$>$3.5). This effect is also observed in quasars with lower luminosities (down to $ The increase in the fraction of FSRQs with redshift corresponds to a decrease in the steep- spectrum radio quasars. This result can be explained when we assume that the beaming factor and the slope of the luminosity function do not change with redshift and if high-redshift radio-loud sources can be recognized as quasars only when they are seen at a small viewing angle ($ but most of them, about 90 are obscured in the UV and optical bands. We also found a trend for the size of radio sources to decrease with increasing redshift. Because projection effects are insufficient to cause this trend, we suggest that the large amount of gas causing the nuclear obscuration also hampers the growth of the more distant sources.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"55 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141689247","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":"Optical polarimetry study of the Lambda-Orionis star-forming region","authors":"S. Neha, A. Soam, G. Maheswar","doi":"10.1051/0004-6361/202449720","DOIUrl":"https://doi.org/10.1051/0004-6361/202449720","url":null,"abstract":"We present an optical polarimetry study of the nearby star-forming region Lambda-Orionis to map the plane-of-the-sky magnetic field geometry to understand the magnetized evolution of the HII region and the associated small molecular clouds. We made multiwavelength polarization observations of 34 bright stars distributed across the region. We also present the R-band polarization measurements that focused on the small molecular clouds, bright-rimmed clouds (BRC), BRC 17, and BRC 18, which are located at the periphery of the HII region. The magnetic field lines exhibit a large-scale ordered orientation consistent with the Planck submillimeter polarization measurements. The magnetic field lines in the two BRCs are found to be roughly in north-south directions. However, a larger dispersion is noted in the orientation for BRC 17 compared to BRC 18. Using a structure-function analysis, we estimate the strength of the plane-of-the-sky component of the magnetic field as sim 28 mu G for BRC 17 and sim 40 mu G for BRC 18. The average dust grain size and the mean value of the total-to-selective extinction ratio (R$_ V $) in the HII region are found to be sim 0.51 pm 0.05 mu m and sim 2.9 pm 0.3, respectively. The distance of the whole HII region is estimated as sim 392 pm 8 pc by combining astrometry information from Global Astrometric Interferometer for Astrophysics (Gaia) early data release 3 (EDR3) for young stellar objects associated with BRCs and confirmed members of the central cluster Collinder 69.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"57 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141338763","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":"Follow-up LOFAR observations of the tau Boötis exoplanetary system","authors":"Jake D. Turner, J. Grießmeier, P. Zarka, Xiang Zhang, E. Mauduit","doi":"10.1051/0004-6361/202450095","DOIUrl":"https://doi.org/10.1051/0004-6361/202450095","url":null,"abstract":"o tis (tau Boo) exoplanetary system was tentatively detected using LOFAR (LOW-Frequency ARray) beamformed observations. If confirmed, this detection will be a major contribution to exoplanet science. However, follow-up observations are required to confirm this detection. Here, we present such follow-up observations of the tau Boo system using LOFAR. These observations cover 70$$ of the orbital period of tau Boo b including the orbital phases of the previous tentative detections. We used the BOREALIS pipeline to mitigate radio frequency interference and to search for bursty and slowly varying radio signals. BOREALIS was previously used to find the tentative radio signals from tau Boo. o tis exoplanetary system. o tis exoplanetary system.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"17 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141338817","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":"Period-luminosity and period-luminosity-metallicity relations for Galactic RR Lyrae stars in the Sloan bands","authors":"W. Narloch, G. Hajdu, G. Pietrzyński, W. Gieren, B. Zgirski, P. Wielgórski, P. Karczmarek, M. Górski, D. Graczyk","doi":"10.1051/0004-6361/202450364","DOIUrl":"https://doi.org/10.1051/0004-6361/202450364","url":null,"abstract":"RR Lyrae stars are excellent tracers of the old population II \u0000 due to their period-luminosity \u0000 (PL) and period-luminosity-metallicity (PLZ) relations. While these relations have been investigated\u0000 in detail in many photometric bands, there are few comprehensive studies about them in Sloan-like \u0000 systems. We present PL and PLZ relations \u0000 (as well as their counterparts in Wesenheit magnitudes) in the Sloan--Pan-STARSS \u0000 $g_ P1 r_ P1 i_ P1 $ bands obtained for Galactic RR Lyrae stars in the vincinity of the Sun. The data used in this paper were collected with the network of $40$ cm telescopes of the \u0000 Las Cumbres Observatory, and geometric parallaxes were adopted from Gaia Data Release $3$. We derived PL and PLZ relations separately for RRab and RRc-type stars, as well as for the \u0000 mixed population of RRab+RRc stars. To our knowledge, these are the first PL and PLZ relations in the Sloan bands determined \u0000 using RR Lyrae stars in the Galactic field.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"47 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141343810","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":"Infrared emissivity of icy surfaces. Sensitivity to regolith properties and water-ice contaminants","authors":"C. Ferrari","doi":"10.1051/0004-6361/202449479","DOIUrl":"https://doi.org/10.1051/0004-6361/202449479","url":null,"abstract":"Most analyses of the infrared emission of Saturn's rings and icy satellites have considered pure water ice as the constituent of regolith and particle surfaces. Visual and near-infrared observations have shown, however, that darkening and reddening contaminants are present at a fraction level of a few percent. In the spectral domain 10-2000 $ cm^ $, water ice becomes transparent in a few windows, which in particular causes the roll-off of emissivity of icy surfaces that is observed below 50 $ cm^ $. Their emissivity there may be affected by these contaminants. We present a quantitative global sensitivity analysis of a hybrid Mie-Hapke model to evaluate the influence of regolith properties and contaminant fraction on the infrared emissivity of icy rings or moons over this spectral range. A hybrid Mie-Hapke model of the hemispherical emissivity $ was made, including various diffraction correction and mixing types with tholins or amorphous carbon grains, or grain size distributions and some anisotropy in emission. A Sobol global sensitivity analysis provided quantitative levels of importance for these factors versus wave number $w_n$. Given the a priori uncertainties, the most important factor acting on $ remains the size distribution of regolith grains and the average anisotropy factor xi . For $w_n$> 50 $ cm^ $, xi , the power-law index $p$ and the minimum $a_ min $ of the size distribution are most influential. In windows of water-ice transparency (10-50, 300-600, and 900-1300 $ cm^ $), the emissivity is also sensitive, but to a lesser extent, to the maximum grain size $a_ max $ and the fraction $f$ of contaminants, if mixed at the molecular level. This model provides a self-consistent tool for interpreting multi-modal observations of the thermal emission from icy surfaces. It also offers interesting insights into recent mid-infrared observations of Saturn's rings and Jupiter's moon Ganymede by the JWST-MIRI instrument.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"55 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141342245","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":"First very long baseline interferometry detection of FornaxA","authors":"G. Paraschos, M. Wielgus, P. Benke, V. Mpisketzis, F. Rösch, K. Dasyra, E. Ros, M. Kadler, R. Ojha, P. G. Edwards, L. Hyland, J. Quick, S. Weston","doi":"10.1051/0004-6361/202450590","DOIUrl":"https://doi.org/10.1051/0004-6361/202450590","url":null,"abstract":"Radio galaxies harbouring jetted active galactic nuclei are a frequent target of very-long-baseline interferometry (VLBI) because they play an essential role in exploring how jets form and propagate.\u0000Hence, only few have not been detected with VLBI yet; is one of the most famous examples. Here we present the first detection of the compact core region of with VLBI. At 8.4,GHz the faint core is consistent with an unresolved point source. We constrained its flux density to be $S_0= and its diameter to be $D_0^ min The high values of the measured brightness temperature ($T_ B K $) imply that the observed radiation is of non-thermal origin, likely associated with the synchrotron emission from the active galactic nucleus.\u0000We also investigated the possibility of a second radio source being present within the field of view.\u0000Adding a second Gaussian component to the geometrical model-fit does not significantly improve the quality of the fit and we, therefore, conclude that our detection corresponds to the compact core of Analysis of the non-trivial closure phases provides evidence for the detection of more extended flux density, on the angular scale of $ Finally, the fractional circular polarisation of the core is consistent with zero, with a conservative upper limit being $m_ circ","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"31 36","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141340489","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":"Extended CO(1-0) survey and ammonia measurements towards two bubble regions in W5. Feedback on molecular gas and clumps","authors":"Hailiang Shen, J. Esimbek, C. Henkel, Ye Xu, Jianjun Zhou, Da-lei Li, Yuxin He, Xindi Tang, Gang Wu, T. Komesh, K. Tursun, Dongdong Zhou, Ernar Imanaly., Dilda Berdikhan.","doi":"10.1051/0004-6361/202347972","DOIUrl":"https://doi.org/10.1051/0004-6361/202347972","url":null,"abstract":"The feedback effect of massive stars can either accelerate or inhibit star formation activity within molecular clouds. Studying the morphology of molecular clouds near W5 offers an excellent opportunity to examine this feedback effect. We conducted a comprehensive survey of the W5 complex using the Purple Mountain Observatory 13.7,m millimeter telescope. This survey includes 12CO, 13CO, and C18O ($J$ = 1--0), with a sky coverage of 6.6 $ deg^2$ circ l circ circ b circ $). Furthermore, we performed simultaneous observations of the NH$_3$ (1,1) and NH$_3$ (2,2) lines in the four densest star-forming regions of W5, using the 26,m radio telescope of the Xinjiang Astronomy Observatory (XAO). Our analysis of the morphological distribution of the molecular clouds, distribution of high-mass young stellar objects (HMYSOs), 13CO/C18O abundance ratio, and the stacked average spectral line distribution at different 8mu m thresholds provide compelling evidence of triggering. Within the mapped region, we identified a total of 212 molecular clumps in the 13CO cube data using the astrodendro algorithm. Remarkably, approximately 26.4$$ (56) of these clumps demonstrate the potential to form massive stars and 42.9$$ (91) of them are gravitationally bound. Within clumps that are capable of forming high-mass stars, there is a distribution of class,I YSOs, all located in dense regions near the boundaries of the ii regions. The detection of NH$_3$ near the most prominent cores reveals moderate kinetic temperatures and densities (as CO). Comparing the $T_ kin $ and $T_ ex $ values reveals a reversal in trends for AFGL,4029 (higher ex $ and lower $T_ kin $) and W5-w1, indicating the inadequacy of optically thick CO for dense region parameter calculations. Moreover, a comparison of the intensity distributions between NH$_3$ (1,1) and C18O (1-0) in the four densest region reveals a notable depletion effect in AFGL,4029, characterised by a low kin $ (9,K) value and a relatively high NH$_3$ column density, 2.5times $. By classifying the 13CO clumps as: \"feedback,\" \"non-feedback,\" \"outflow,\" or \"non-outflow\" clumps, we observe that the parameters of the \"feedback\" and \"outflow\" clumps exhibit variations based on the intensity of the internal 8mu m flux and the outflow energy, respectively. These changes demonstrate a clear linear correlation, which distinctly separate them from the parameter distributions of the \"non-feedback\" and \"non-outflow\" clumps, thus providing robust evidence to support a triggering scenario.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"43 38","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141339881","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":"Investigating and comparing the IRIS spectral lines Mg ii, Si iv, or C ii for flare precursor diagnostics","authors":"Jonas Zbinden, L. Kleint, Brandon Panos","doi":"10.1051/0004-6361/202347824","DOIUrl":"https://doi.org/10.1051/0004-6361/202347824","url":null,"abstract":"Context : Reliably predicting solar flares can mitigate the risks of technological damage and enhance scientific output by providing reliable pointings for observational campaigns. Flare precursors in the spectral line Mg ii have been identified. Aims : We extend previous studies by examining the presence of flare precursors in additional spectral lines, such as Si iv and C ii over longer time windows, and for more observations. Methods : We trained neural networks and XGBoost decision trees to distinguish spectra observed from active regions that lead to a flare and those that did not. To enhance the information within each observation, we tested different masking methods to preprocess the data. Results : We find average classification true skill statistics (TSS) scores of $0.53$ for Mg ii $0.44$ for Si iv and $0.42$ for C ii . We speculate that Mg ii h k performs best because it samples the highest formation height range, and is sensitive to heating and density changes in the mid- to upper chromosphere. The flaring area relative to the field of view has a large effect on the model classification score and needs to be accounted for. Combining spectral lines has proven difficult, due to the difference in areas of high probability for an imminent flare between different lines. Conclusion : Our models extract information from all three lines, independent of observational bias or GOES X-ray flux precursors, implying that the physics encoded in a combination of high resolution spectral data could be useful for flare forecasting.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"45 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141338717","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}