bluuebunny/crossref_metadata_2025_split huggingface dataset:
Iron‐Induced Regio‐ and Stereoselective Addition of Sulfenyl Chlorides to Alkynes by a Radical Pathway
Authors: Iwasaki Masayuki , Fujii Tomoya , Nakajima Kiyohiko , Nishihara Yasushi 
Published: October 2014

AbstractThe radical addition of the ClS σ‐bond in sulfenyl chlorides to various CC triple bonds has been achieved with excellent regio‐ and stereoselectivity in the presence of a catalytic amount of a common iron salt. The reaction is compatible with a variety of functional groups and can be scaled up to the gram‐scale with no loss in yield. As well as terminal alkynes, internal alkynes underwent stereodefined chlorothiolation to provide tetrasubstituted alkynes. Preliminary mechanistic investigations revealed a plausible radical process involving a sulfur‐centered radical intermediate via iron‐mediated homolysis of the ClS bond. The resulting chlorothiolation adducts can be readily transformed to the structurally complex alkenyl sulfides by cross‐coupling reactions. The present reaction can also be applied to the complementary synthesis of the potentially useful bis‐sulfoxide ligands for transition‐metal‐catalyzed reactions.
Mitochondria‐Targeted Cancer Therapy Using a Light‐Up Probe with Aggregation‐Induced‐Emission Characteristics
Authors: Hu Qinglian , Gao Meng , Feng Guangxue , Liu Bin 
Published: October 2014

AbstractSubcellular organelle‐specific reagents for simultaneous tumor targeting, imaging, and treatment are of enormous interest in cancer therapy. Herein, we present a mitochondria‐targeting probe (AIE‐mito‐TPP) by conjugating a triphenylphosphine (TPP) with a fluorogen which can undergo aggregation‐induced emission (AIE). Owing to the more negative mitochondrial membrane potential of cancer cells than normal cells, the AIE‐mito‐TPP probe can selectively accumulate in cancer‐cell mitochondria and light up its fluorescence. More importantly, the probe exhibits selective cytotoxicity for studied cancer cells over normal cells. The high potency of AIE‐mito‐TPP correlates with its strong ability to aggregate in mitochondria, which can efficiently decrease the mitochondria membrane potential and increase the level of intracellular reactive oxygen species (ROS) in cancer cells. The mitochondrial light‐up probe provides a unique strategy for potential image‐guided therapy of cancer cells.
Environmental dependence of stellar mass, SFR, and SSFR for the Luminous Red Galaxy (LRG) sample of the SDSS DR7
Authors: Deng X.‐F. , Yang B. , Ding Y.‐P. , Jiang P. 
Published: October 2014

AbstractUsing the Luminous Red Galaxy (LRG) sample of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), we investigate the environmental dependence of stellar mass, star formation rate (SFR) and specific star formation rate (SSFR) of LRGs. It is found that stellar mass of LRGs nearly is independent of local environments, and that the environmental dependence of SFR and SSFR in the LRG sample is much weaker than the one in the Main galaxy sample. One possible explanation is that galaxy color and morphology are a pair of galaxy properties most predictive of local environments, while LRGs are a group of galaxies that are likely to be luminous, red and of early types (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of Korean astronomical records with Chinese equatorial coordinates
Authors: Lee K.W. 
Published: October 2014

AbstractThe historical documents of ancient Korea contain abundant records on various astronomical phenomena. The historical documents of the Joseon dynasty contain observational values based on Chinese equatorial coordinate system (i.e., angular distances from the reference star of a lunar mansion and the North Pole). However, quantitative analysis of the observational values has not been carried out. In this study, we investigate the observational accuracy during the Joseon dynasty by comparing the astronomical records of Joseonwangjo Sillok (Annals of the Joseon Dynasty) and Seungjeongwon Ilgi (Daily Records of the Royal Secretariat) with modern astronomical calculations. Consequently, we find that the observational accuracy during the early Joseon dynasty was approximately 1°.2 and 0°.3 in the right ascension and declination, respectively. On the other hand, we find that the observational accuracy during the later Joseon dynasty was considerably poor. Observations of Halley's comet in 1759 were off by approximately 7° in declination. We believe that further investigation is required to verify the reason for this poor accuracy. Thus, we list the complete records used for this study in the appendix. We believe that these records also can contribute to modern studies on phenomena such as supernovae or Halley's comet. In conclusion, we believe that this study is useful for understanding ancient Korean astronomical records, even though we have considered a small number of astronomical events (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
CN rotational excitation
Authors: Krełowski J. , Galazutdinov G. , Gnaciński P. 
Published: October 2014

AbstractWe demonstrate, using a sample of high quality spectra, that the average equivalent width ratio of the unsaturated R(0) and R(1) lines of the CN B2Σ+ – X2Σ+ (0, 0) band near 3875 Å equals π instead of 3.73 – calculated for the CMBR temperature T = 2.725 K and the already published oscillator strengths of both transitions, i.e. the excitation temperature of CN is slightly higher than it should be expected if CMBR is the only excitation mechanism. Taking into account the saturation effects by means of profile fitting during the column density calculations does not remove the revealed temperature excess. Possible interpretations of the effect are discussed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The significance of the Hansen Ideal space frame
Authors: Jochim E.F.M. 
Published: October 2014

AbstractKnown and unknown properties of Hansen Ideal coordinates are summarized. It is shown that the ideal space frame is a general and necessary component of basic celestial mechanics and astrodynamics, as well as of any theory of motion. A typical consequence is the intimate correlation of the Hansen frame with the Lagrange constraint within the method of the variation of the parameters. The use of observations in the ideal frame may allow conclusions on the intergalactic fundamental coordinate system (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The hemispheric variation of the flare index during solar cycles 20–23
Authors: Deng L.H. , Qu Z.Q. , Liu T. , Wang K.R. 
Published: October 2014

AbstractIn this paper, the monthly counts of flare index in the northern and southern hemispheres are used to investigate the hemispheric variation of the flare index in each of solar cycles 20–23. It is found that, (1) the flare index is asymmetrically distributed in each solar cycle and its asymmetry is a real phenomenon; (2) the flare index in the northern hemisphere begins earlier than that in the southern hemisphere in each of solar cycles 20–23, and the phase shifts between the two hemispheres show an odd‐even pattern; (3) although the flare index dominating in a hemisphere does not mean that it leads in phase in this hemisphere in individual solar cycle, these two features have an intrinsic relationship. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cosmic Flows surveys and CLUES simulations
Authors: Courtois H.M. , Tully R.B. 
Published: October 2014

Abstract‘Cosmic Flows’ is a program to determine galaxy distances for 30000 galaxies with systematic errors below 2%, almost ten times the number currently known and a five‐fold improvement in systematics. The resultant velocity field will provide input for constrained local universe simulations: CLUES (www.clues‐project.org). The observed and the simulated universe are then comparatively studied. This synergy of observations and theory distinguishes the program, and should lead to fundamental discoveries regarding the sources of deviations from the expansion of the universe. Specifically, the program should give a definitive answer to one of the most outstanding unsolved problem in cosmology: the cause of the motion of 630 km s–1 of our Galaxy manifested in the microwave background dipole. This paper presents current results with particular emphasis on the “great attractor” reconstruction (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Milky Way simulations: The Galaxy, its stellar halo and its satellites – insights from a hybrid cosmological approach
Authors: De Lucia G. 
Published: October 2014

AbstractOur home galaxy – the Milky Way – is a fairly large spiral galaxy, prototype of the most common morphological class in the local Universe. Although being only a galaxy, it is the only one that can be studied in unique detail: for the Milky Way and for a number of members of the Local Group, a wealth of observational data is available about the ages and chemical abundances of their stars. Much more information is expected to come in the next few years, from ongoing and planned spectroscopic and astrometric surveys, providing a unique benchmark for modern theories of galaxy formation. In this review, I will summarize recent results on the formation of our Milky Way, its stellar halo, and its satellite galaxies. I will focus, in particular, on results obtained in the framework of hybrid models of galaxy formation, and refer to other reviews in this issue for studies based on hydrodynamical simulations (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gamma‐ray burst host galaxies at low and high redshift
Authors: Savaglio S. 
Published: October 2014

AbstractThe galaxies hosting the most energetic explosions in the universe, the gamma‐ray bursts (GRBs), are generally found to be low‐mass, metal poor, blue and star forming galaxies. However, the majority of the targets investigated so far (less than 100) are at relatively low redshift, z < 2. We know that at low redshift, the cosmic star formation is predominantly in small galaxies. Therefore, at low redshift, long‐duration GRBs, which are associated with massive stars, are expected to be in small galaxies. Preliminary investigations of the stellar mass function of z < 1.5 GRB hosts does not indicate that these galaxies are different from the general population of nearby star‐forming galaxies. At high‐z, it is still unclear whether GRB hosts are different. Recent results indicate that a fraction of them might be associated with dusty regions in massive galaxies. Remarkable is the a super‐solar metallicity measured in the interstellar medium of a z = 3.57 GRB host (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New results from Galactic ISM surveys: The frothy ISM
Authors: McClure‐Griffiths N.M. 
Published: October 2014

AbstractThe past 10 years have seen a resurgence in studies of the Milky Way's interstellar medium (ISM) driven by new surveys of the Galactic plane at wavelengths from 4 microns to 20 cm. These surveys, which include the H I International Galactic Plane Survey, the Spitzer GLIMPSE and MIPSGAL surveys, the recently commenced Herschel HI‐GAL survey, and several surveys of CO J = 1–0, are allowing us to trace the evolution of the ISM on scales of parsecs and sub‐parsecs from warm and diffuse through to cold, dusty molecular gas. Together with hydrodynamical simulations of ever‐increasing sophistication our understanding of the ISM in the disk of the Milky Way has evolved from the 1970's simplistic models of cold clouds surrounded by warm gas to a complex mixture of phases intertwined and interconnected, whose cooling is driven by colliding flows. Here I focus on the “frothy” ISM, where structure and evolution is impacted by bubbles, shells and supershells. I discuss the role of these objects in cooling, the formation of molecules and even the transfer of matter out of the disk of the Galaxy (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The extinction curve in the visible and the value of RV: Addendum to AN 333, 160
Authors: Zagury F. , Turner D.G. 
Published: October 2014

AbstractThis paper corrects and completes a previous study of the shape of the extinction curve in the visible and the value of RV. A continuous visible/infrared extinction law proportional to 1/λp with p close to 1 (± 0.4) is indistinguishable from a perfectly linear law (p = 1) in the visible within observational precision, but the shape of the curve in the infrared can be substantially modified. Values of p slightly larger than 1 would account for the increase of extinction (compared to the p = 1 law) reported for λ > 1 μ m and deeply affect the value of RV. In the absence of gray extinction RV must be 4.04 if p = 1. It becomes 3.14 for p = 1.25, 3.00 for p = 1.30, and 2.76 for p = 1.40. Values of p near 1.3 are also attributed to extinction by atmospheric aerosols, which indicates that both phenomena may be governed by similar particle size distributions. A power extinction law may harmonize visible and infrared data into a single, continuous, and universal interstellar extinction law (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Larger, faster, better: Current trends in cosmological simulations
Authors: Springel V. 
Published: October 2014

AbstractNumerical simulations of galaxy formation provide a powerful technique for calculating the non‐linear evolution of cosmic structure formation. In fact, they have played an instrumental role in establishing the current standard cosmological model known as ΛCDM. In this brief review, I highlight some of largest calculations carried out recently in the field, and I discuss the challenges involved in making further progress with simulations in the future. These entail the need to scale up the simulations to ever larger sizes and much better resolution, the need to develop more comprehensive numerical models of the physics of galaxy formation, and the need to improve the accuracy of the numerical techniques currently employed. The present epoch of petaflop supercomputers, and the exaflop machines that are foreseen towards the end of the decade, demand novel types of simulation codes that yet have tobe developed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
GJ 581 update: Additional evidence for a Super‐Earth in the habitable zone
Authors: Vogt S.S. , Butler R.P. , Haghighipour N. 
Published: October 2014

AbstractWe present an analysis of the significantly expanded HARPS 2011 radial velocity data set for GJ 581 that was presented by Forveille et al. (2011). Our analysis reaches substantially different conclusions regarding the evidence for a Super‐Earth‐mass planet in the star's Habitable Zone. We were able to reproduce their reported χ2ν and RMS values only after removing some outliers from their models and refitting the trimmed down RV set. A suite of 4000 N‐body simulations of their Keplerian model all resulted in unstable systems and revealed that their reported 3.6σ detection of e = 0.32 for the eccentricity of GJ 581e is manifestly incompatible with the system's dynamical stability. Furthermore, their Keplerian model, when integrated only over the time baseline of the observations, significantly increases the χ2ν and demonstrates the need for including non‐Keplerian orbital precession when modeling this system. We find that a four‐planet model with all of the planets on circular or nearly circular orbits provides both an excellent self‐consistent fit to their RV data and also results in a very stable configuration. The periodogram of the residuals to a 4‐planet all‐circular‐orbit model reveals significant peaks that suggest one or more additional planets in this system. We conclude that the present 240‐point HARPS data set, when analyzed in its entirety, and modeled with fully self‐consistent stable orbits, by and of itself does offer significant support for a fifth signal in the data with a period near 32 days. This signal has a false alarm probability of <4% and is consistent with a planet of minimum mass 2.2 M⊕, orbiting squarely in the star's habitable zone at 0.13 AU, where liquid water on planetary surfaces is a distinct possibility (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The opacity of spiral galaxy disks: IX. Dust and gas surface densities
Authors: Holwerda B.W. , Allen R.J. , de Blok W.J.G. , Bouchard A. , González‐Lópezlira R.A. , van der Kruit P.C. , Leroy A. 
Published: October 2014

AbstractOur aim is to explore the relation between gas, atomic and molecular, and dust in spiral galaxies. Gas surface densities are from atomic hydrogen and CO line emission maps. To estimate the dust content, we use the disk opacity as inferred from the number of distant galaxies identified in twelve HST/WFPC2 fields of ten nearby spiral galaxies. The observed number of distant galaxies is calibrated for source confusion and crowding with artificial galaxy counts and here we verify our results with sub‐mm surface brightnesses from archival Herschel ‐SPIRE data. We find that the opacity of the spiral disk does not correlate well with the surface density of atomic (H I) or molecular hydrogen (H2) alone implying that dust is not only associated with the molecular clouds but also the diffuse atomic disk in these galaxies. Our result is a typical dust‐to‐gas ratio of 0.04, with some evidence that this ratio declines with galactocentric radius, consistent with recent Herschel results. We discuss the possible causes of this high dust‐to‐gas ratio; an over‐estimate of the dust surface‐density, an under‐estimate of the molecular hydrogen density from CO maps or a combination of both. We note that while our value of the mean dust‐to‐gas ratio is high, it is consistent with the metallicity at the measured radii if one assumes the Pilyugin & Thuan (2005) calibration of gas metallicity. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New classification and basic stellar parameter of SW Equulei
Authors: Behre O. , Hünsch M. 
Published: October 2014

AbstractWe review the classification of the variable star SW Equulei, formerly classified as a close binary of the W UMa type with a period of 0.83632 d and components of spectral types O–A or F–G and later. New observations indicate that the light curve is not that of an eclipsing binary but of a pulsating star with a period half of the old value. Further examination shows that SW Equulei is a double mode star of the RRd Lyrae type with a fundamental period of P = 0.560727 d and an overtone of P = 0.4181777 d at a distance of ≈ 7.1 kpc. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
CSS091109:035759+102943: A candidate polar
Authors: Schwope A.D. , Thinius B. 
Published: October 2014

AbstractWe report optical time‐resolved photometry of the CRTS transient CSS091109:035759+102943. Pronounced orbital variability with a 114 min period, large X‐ray variability and the IR to X‐ray spectral energy distribution suggest a classification as a magnetic cataclysmic binary, a likely AM Herculis star or polar (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rotation, activity, and lithium abundance in cool binary stars
Authors: Strassmeier K. G. , Weber M. , Granzer T. , Järvinen S. 
Published: October 2014

AbstractWe have used two robotic telescopes to obtain time‐series high‐resolution optical echelle spectroscopy and VI and/or by photometry for a sample of 60 active stars, mostly binaries. Orbital solutions are presented for 26 double‐lined systems and for 19 single‐lined systems, seven of them for the first time but all of them with unprecedented phase coverage and accuracy. Eighteen systems turned out to be single stars. The total of 6609 R = 55000 échelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute Hα‐core fluxes as a function of time. The photometry is used to infer unspotted brightness, V – I and/or b – y colors, spot‐induced brightness amplitudes and precise rotation periods. An extra 22 radial‐velocity standard stars were monitored throughout the science observations and yield a new barycentric zero point for our STELLA/SES robotic system. Our data are complemented by literature data and are used to determine rotation‐temperature‐activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74% of all known rapidly‐rotating active binary stars are synchronized and in circular orbits but 26% (61 systems) are rotating asynchronously of which half have Prot > Porb and e > 0. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin‐down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars, Prot α T–7eff, for both single and binaries, main sequence and evolved. For inactive, single giants with Prot > 100 d, the relation is much weaker, Prot α T‐1.12eff. Our data also indicate a period‐activity relation for Hα of the form RHα α P0.24rot for binaries and RHα α P‐0.14rot for singles. Its power‐law difference is possibly significant. Lithium abundances in our (field‐star) sample generally increase with effective temperature and are paralleled with an increase of the dispersion. The dispersion for binaries can be 1–2 orders of magnitude larger than for singles, peaking at an absolute spread of 3 orders of magnitude near Teff ≈ 5000 K. On average, binaries of comparable effective temperature appear to exhibit 0.25 dex less surface lithium than singles, as expected if the depletion mechanism is rotation dependent. We also find a trend of increased Li abundance with rotational period of form log n (Li) α –0.6 log Prot but again with a dispersion of as large as 3‐4 orders of magnitude (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mining the ESO WFI and INT WFC archives for known Near Earth Asteroids. Mega‐Precovery software
Authors: Vaduvescu O. , Popescu M. , Comsa I. , Paraschiv A. , Lacatus D. , Sonka A. , Tudorica A. , Birlan M. , Suciu O. , Char F. , Constantinescu M. , Badescu T. , Badea M. , Vidican D. , Opriseanu C. 
Published: October 2014

AbstractThe ESO/MPG WFI and the INT WFC wide field archives comprising 330 000 images were mined to search for serendip‐itous encounters of known Near Earth Asteroids (NEAs) and Potentially Hazardous Asteroids (PHAs). A total of 152 as‐teroids (44 PHAs and 108 other NEAs) were identified using the PRECOVERY software, their astrometry being measured on 761 images and sent to the Minor Planet Centre. Both recoveries and precoveries were reported, including prolonged orbital arcs for 18 precovered objects and 10 recoveries. We analyze all new opposition data by comparing the orbits fitted before and after including our contributions. We conclude the paper presenting “Mega‐Precovery”, a new online service focused on data mining of many instrument archives simultaneously for one or a few given asteroids. A total of 28 instrument archives have been made available for mining using this tool, adding together about 2.5 million images forming the “Mega‐Archive”