bluuebunny/crossref_metadata_2025_split huggingface dataset:
Apparent brightness distribution of GRB host galaxies
Authors: Bagoly Zsolt , Rácz István I. , Balázs Lajos G. , Horváth István , Tóth L. Viktor 
Published: September 2016

AbstractWe studied the unbiased optical brightness distribution which was calculated from the survival analysis of host galaxies (HGs) data and its relationship with the Swift GRB data of the host galaxies observed by the Keck telescope. Based on the sample obtained from merging the Swift GRB table and the Keck optical data we also studied the dependence of this distribution on the GRB's data. Finally, we compared the HGs distribution with standard galaxies distribution of the DEEP2 redshift survey and checked the result with the VIPERS catalogue too.
The WISE Census of Young Stellar Objects and Clusters in Canis Major
Authors: Fischer W. J. , Padgett D. L. , Stapelfeldt K. R. 
Published: September 2016

AbstractThe photometric data returned by WISE, the Wide-field Infrared Survey Explorer, can be used to search the sky for young stellar objects (YSOs) away from the molecular clouds studied in detail by Spitzer and Herschel. We present updated results for a 100 deg2 region centered on Canis Major, including a look at the clustering properties of YSOs in the region.
Dust Extinction toward SN 2014J in M82
Authors: Gao Jian , Jiang B. W. , Li Aigen 
Published: September 2016

AbstractWe derive the extinction toward SN 2014J, a Type Ia supernova in M82, as a function of wavelength from the far ultraviolet to the near infrared by modeling the observed color excesses in terms of a mixture of silicate and graphite. With Av ≈ 1.9 mag and RV ≈ 1.7-1.8, the derived extinction law differs substantially from those of the Galaxy and the Magellanic clouds.
Properties of the ISM in UV-luminous galaxies: clues from the low-redshift universe
Authors: Gonçalves Thiago S. 
Published: September 2016

AbstractHow is gas converted into stars across cosmic time? Observations of star-forming galaxies at high redshift indicate that the conditions of the interstellar medium (ISM) were remarkably distinct from typical spirals in the local universe. Nevertheless, these observations are biased towards objects brighter than L*, due to the large luminosity distances involved. Here I present a survey targeting the molecular gas in galaxies at low redshift (z ~ 0.2) with ISM conditions remarkably similar to those observed at earlier epochs, including high star formation rates and lower metallicities. CO observations performed with CARMA indicate that these galaxies follow the same star-formation law as local spirals and other galaxies at the same redshift, albeit at much higher densities. We also present recent results from our ALMA program studying galaxies down to 12 + log(O/H) ~ 8, and discuss the implications of these data to our understanding of the molecular gas reservoir and the conversion factor between CO luminosity and gas mass in environments that are simultaneously low in metal content and extremely dense.
SWAN: NGC 253's Nucleated Star Bursting Environment
Authors: Gorski Mark , Ott Jürgen , Meier David , Momjian Emmanuel , Walter Fabian , Rand Richard 
Published: September 2016

AbstractWe present the first results from SWAN: “Survey of Water and Ammonia in Nearby galaxies”. Nearby galaxies are conveniently located to probe molecular gas properties on scales of 10 to 200 pc, which are appropriate for the study of Giant Molecular Clouds (GMCs). The resolution of the Very Large Array in D and C configurations corresponds to a few 10s of parsecs in these galaxies. To advance studies of galaxy evolution it is paramount to understand how processes in the molecular Interstellar Medium(ISM) and star formation are linked on these scales. We have observed the metastable transitions of ammonia and the 22GHz water maser line in four nearby galaxies: NGC 253, IC 342, NGC 2146, and NGC 6946 using the VLA. These galaxies were chosen to span an order of magnitude in star formation rate, and a range of galactic ecosystems. We use the ammonia transitions to derive kinetic temperatures, which exposes the heating and cooling balance of the ISM. We then aim to relate these conditions to energetic feedback from star formation as indicated by water masers.Currently, our analysis is focused on NGC 253. NGC 253 is a barred spiral starburst galaxy with a nucleated star formation rate (SFR) of ≈ 3M⊙ per year. We use a distance of 3.9Mpc for analysis. We have observed ammonia transitions (1,1) to (5,5) and the 22GHz water maser line with a resolution of ≈63pc. We have identified nine regions across the nucleated starburst for study. The ammonia (3,3) line appears to be masing in the centermost 200pc. We have identified two regions of water maser emission. The first region is a minor axis extension, about the center of the galaxy, and is very close to the outflow. By means of these measurements, we gain an understanding of the molecular ISM associated with the nucleated starburst environment in NGC 253.
Chemical Tracers of Pre-Brown Dwarf Cores Formed Through Turbulent Fragmentation
Authors: Holdship Jonathan , Viti Serena 
Published: September 2016

AbstractA gas-grain time dependent chemical code, UCL_CHEM, has been used to investigate the possibility of using chemical tracers to differentiate between the possible formation mechanisms of brown dwarfs. We model the formation of a pre-brown dwarf core through turbulent fragmentation by following the depth-dependent chemistry in a molecular cloud through the step change in density associated with an isothermal shock and the subsequent freefall collapse once a bound core is produced. Trends in the fractional abundance of molecules commonly observed in star forming cores are then explored to find a diagnostic for identifying brown dwarf mass cores formed through turbulence. We find that the cores produced by our models would be bright in CO and NH3 but not in HCO+. This differentiates them from models using purely freefall collapse as such models produce cores that would have detectable transitions from all three molecules.
ALFALFA Hα Reveals How Galaxies Use Their Hi Fuel
Authors: Jaskot Anne , Oey Sally , Salzer John , Van Sistine Angie , Bell Eric , Haynes Martha 
Published: September 2016

AbstractAtomic hydrogen traces the raw material from which molecular clouds and stars form. With 565 galaxies from the ALFALFA Hα survey, a statistically complete subset of the ALFALFA survey, we examine the processes that affect galaxies' abilities to access and consume their Hi gas. On galaxy-wide scales, Hi gas fractions correlate only weakly with instantaneous specific star formation rates (sSFRs) but tightly with galaxy color. We show that a connection between dust and Hi content, arising from the fundamental mass-metallicity-Hi relation, leads to this tight color correlation. We find that disk galaxies follow a relation between stellar surface density and Hi depletion time, consistent with a scenario in which higher mid-plane pressure leads to more efficient molecular cloud formation from Hi. In contrast, spheroids show no such trend. Starbursts, identified by Hα equivalent width, do not show enhanced Hi gas fractions relative to similar mass non-starburst galaxies. The starbursts' shorter Hi depletion times indicate more efficient consumption of Hi, and galaxy interactions drive this enhanced star formation efficiency in several starbursts. Interestingly, the most disturbed starbursts show greater enhancements in Hi gas fraction, which may indicate an excess of Hi at early merger stages. At low galaxy stellar masses, the triggering mechanism for starbursts is less clear; the high scatter in efficiency and sSFR among low-mass galaxies may result from periodic bursts. We find no evidence for depleted Hi reservoirs in starbursts, which suggests that galaxies may maintain sufficient Hi to fuel multiple starburst episodes.
Possible density dependent local variations in the IMF
Authors: Kavila Indulekha , George Babitha 
Published: September 2016

AbstractA robust feature of turbulent fragmentation theories is a universal Salpeter like slope (2.2 -2.4), for the mass spectrum of the fragments, at the high mass end. This is so due to the scale-free nature of turbulence and gravity. There are reports of top heavy / flatter Initial Mass Functions (IMF), inferred for many regions where we expect star formation to take place in gas clouds with comparatively higher gas density. Also, a higher Star Formation Efficiency (SFE) for regions of higher gas density has been proposed, to understand the formation of bound stellar systems in which dark matter is not a significant factor affecting the internal dynamics. In turbulent fragmentation models for star formation, we do not expect the mass of the stellar cluster to influence the maximum stellar mass directly and thereby imply a relation between the maximum stellar mass and the cluster mass. However, such a relation may be expected from statistical considerations. In this context, we explore the density dependence of the IMF, that would arise due to denser clouds producing more massive clusters due to the density dependence of the SFE.
High-Redshift Protoclusters Traced by Submillimeter Galaxies
Authors: Menéndez-Delmestre Karín , Capak Peter , Sheth Kartik 
Published: September 2016

AbstractClustering analysis indicate that at z ~ 2 submm-selected galaxies (SMGs) reside in very massive halos (MDM > 5 × 1013), suggesting that SMGs trace high-density environments that evolve into rich galaxy clusters. Conversely, recent work suggests that SMGs are tracers of a broader range of environments, including structures with more modest masses caught in highly active periods; since galaxies in these structures are likely caught during episodes of peak starbursts, SMGs may be tracers of a wider range of environments beyond the progenitors of todays very rich clusters, opening a window for a more complete exploration of the details underpinning the process of galaxy evolution in concert with the assembly of the large scale structure (LSS). We have undertaken a large observing program comprising deep narrow-band Ly-alpha imaging and multi-object spectroscopy using Palomar/Keck/Magellan/Gemini telescopes to probe for galaxy overdensities in SMG environments at z ~ 1 − 5. With ~200 spectroscopically-confirmed Ly-alpha emitters, we are in a position to gauge the level of galaxy overdensity in these regions.
What is a GMC? Are observers and simulators discussing the same star-forming clouds?
Authors: Pan Hsi-An , Fujimoto Yusuke , Tasker Elizabeth J. 
Published: September 2016

AbstractObservations and simulations have now reached the point where the giant molecular cloud (GMCs) populations can be studied over a whole galaxy. This is immensely helpful for understanding star formation. Yet, are these two groups really comparing the same objects? While simulators work in 6D (x, y, z, vx, vy, vz) position-position-position (PPP) space, observers see 2 + 1D (RA, Dec, vlos) projected properties along the line of sight, identifying clouds in position-position-velocity (PPV) space. In this research we generated PPP and PPV data for a high-resolution simulated galaxy and compared the identified clouds in both data sets. The results show that 70% of the clouds have a single counterpart in each data structure. Cloud boundaries of these clouds are indeed the same. Scatter of the derived cloud properties (radius and velocity dispersion) between PPP and PPV are typically within a factor of two. However, this small scatter can make it difficult to determine if a cloud is truly gravitationally bound.
Galactic spiral generation in tidal encounters
Authors: Pettitt Alex R. , Tasker Elizabeth J. , Wadsley James W. 
Published: September 2016

AbstractThe existence of grand design spiral galaxies in the universe is still a standing problem. The passage of a small companion is known to be able to induce spiral structures in disc galaxies, but there remains questions over how relevant this mechanism is to the galaxies observed in the real universe. Our study aims to address two key points regarding such interactions; the limiting mass companion needed to drive tidal spiral structures, and the differences between the resulting gas and stellar morphology. We find the minimum mass of a companion to be as low as 5% of the stellar mass of the galaxy, and that the arms formed in the gas and the stars display very minor dynamical and morphological differences.
Core mass function: a comparison study between Orion A and other massive filamentary clouds.
Authors: Ren Zhiyuan , Li Di 
Published: September 2016

AbstractAs a giant compact filamentary cloud, Orion A has a similar morphology with those more distant filaments in infrared dark clouds as revealed in Herschel surveys. We compared their core mass functions and found a similar power law index of N(>m)∝ m−1.0 for the high-mass end, which may possibly indicates a common case for massive filamentary clouds. We also show that the measured mass function for a certain cloud would largely depend on its distance, thus call for caution in interpreting individual measurements of CMF.
CaII Quasar Absorbers: Statistics, Metals, Dust, and Associated Galaxies
Authors: Turnshek David A. , Sardane Gendith M. , Rao Sandhya M. 
Published: September 2016

AbstractWe summarize results from our recent SDSS survey for CaII quasar absorbers. The survey finds 435 absorbers at z<1.34, which corresponds to ~9 Gyrs of the Universe's history. Two CaII absorber populations are identified, which we call weak and strong. Metal abundance ratios derived from normalized composite spectra show that weak absorbers can be identified with halo-like gas, while strong absorbers are a mix of halo+disk-like gas. Consistent with these abundance ratio results, fluxed composites show that strong absorbers are ~6 times more reddened than weak absorbers (i.e., they contain more dust). Four individual examples of galaxies associated with CaII absorption are found in the SDSS images, and three are star forming galaxies (SFGs). Image composites show that galaxies associated with strong absorbers have mean luminosity-weighted impact parameters, b, which are ~2.4 times smaller than the weak absorbers (bstrong ~ 19 kpc versus bweak 45 kpc). Studies of CaII absorbers suggest links to molecular clouds, SFGs, and circumgalactic gas (CGG).
WISE properties of OH megamaser galaxies: Guide for future FAST OHM survey?
Authors: Zhang J.S. , Wang J.Z. , Li D. , Zhu Q.F. 
Published: September 2016

AbstractAll 119 OH maser galaxies (110 out of them are megamasers, i.e., LOH > 10 L⊙, OHMs) published so far were compiled and were cross-identified with the Wide-Field Infrared Survey Explorer (WISE) catalog. Our aim is to investigate intrinsic middle-infrared properties of OH maser galaxies and try to find some hints on sample selections on OHM surveys through the coming Five hundred aperture spherical telescope (FAST). In addition, enormous potentials for OHM surveys by future FAST are investigated, based on its innovative designs and its expected best sensitivity among single dish telescopes.
Binary stars on the galaxy SFH
Authors: Zhang F. , Li L. , Han Z. 
Published: September 2016

AbstractUsing the Yunnan-II evolutionary population synthesis models comprising binary stars, we find that the inclusion of binary stars can raise the derived stellar metallicity Z* and/or age t (degeneracy problem), raise the stellar mass M*, lower the gaseous metallicity Zgas and star formation rate (SFR) of galaxies. This means that a few stars form recently in galaxies, while more stars form during the entire evolution process when considering binary stars. If the degeneracy between t and Z* can be broken, its effect on the feedback process and star formation history can be determined.
Targeting the metabolic pathway of human colon cancer overcomes resistance to TRAIL-induced apoptosis
Authors: Carr Ryan M , Qiao Guilin , Qin Jianzhong , Jayaraman Sundararajan , Prabhakar Bellur S , Maker Ajay V 
Published: September 2016

AbstractColon cancer is a leading cause of cancer-related mortality for which targeted therapy is needed; however, trials using apoptosis-inducing ligand monotherapy to overcome resistance to apoptosis have not shown clinical responses. Since colon cancer cells selectively uptake and rapidly metabolize glucose, a property utilized for clinical staging, we investigated mechanisms to alter glucose metabolism in order to selectively target the cancer cells and to overcome evasion of apoptosis. We demonstrate TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) resistance in the majority of human colon cancers tested and utilize the glucose analog 2-deoxy-d-glucose to sensitize TRAIL-resistant gastrointestinal adenocarcinoma cells, and not normal gastrointestinal epithelial cells, to TRAIL-induced apoptosis through enhanced death receptor 5 expression, downstream modulation of MAPK signaling and subsequent miRNA expression modulation by increasing the expression of miR-494 via MEK activation. Further, established human colon cancer xenografts treated with this strategy experience anti-tumor responses. These findings in colon adenocarcinoma support further investigation of manipulation of cellular energetics to selectively overcome resistance to apoptosis and to impart tumor regressions in established colon cancer tumors.
Mutational signatures of ionizing radiation in second malignancies
Authors: Behjati Sam , Gundem Gunes , Wedge David C. , Roberts Nicola D. , Tarpey Patrick S. , Cooke Susanna L. , Van Loo Peter , Alexandrov Ludmil B. , Ramakrishna Manasa , Davies Helen , Nik-Zainal Serena , Hardy Claire , Latimer Calli , Raine Keiran M. , Stebbings Lucy , Menzies Andy , Jones David , Shepherd Rebecca , Butler Adam P. , Teague Jon W. , Jorgensen Mette , Khatri Bhavisha , Pillay Nischalan , Shlien Adam , Futreal P. Andrew , Badie Christophe ,   ICGC Prostate Group, Cooper Colin S. , Eeles Rosalind A. , Easton Douglas , Foster Christopher , Neal David E. , Brewer Daniel S. , Hamdy Freddie , Lu Yong-Jie , Lynch Andrew G. , Massi Charlie E. , Ng Anthony , Whitaker Hayley C. , Yu Yongwei , Zhang Hongwei , Bancroft Elizabeth , Berney Dan , Camacho Niedzica , Corbishley Cathy , Dadaev Tokhir , Dennis Nening , Dudderidge Tim , Edwards Sandra , Fisher Cyril , Ghori Jilur , Gnanapragasam Vincent J. , Greenman Christopher , Hawkins Steve , Hazell Steven , Howat Will , Karaszi Katalin , Kay Jonathan , Kote-Jarai Zsofia , Kremeyer Barbara , Kumar Pardeep , Lambert Adam , Leongamornlert Daniel , Livni Naomi , Luxton Hayley , Matthews Lucy , Mayer Erik , Merson Susan , Nicol David , Ogden Christopher , O’Meara Sarah , Pelvender Gill , Shah Nimish C. , Tavare Simon , Thomas Sarah , Thompson Alan , Verrill Claire , Warren Anne , Zamora Jorge , McDermott Ultan , Bova G. Steven , Richardson Andrea L. , Flanagan Adrienne M. , Stratton Michael R. , Campbell Peter J. 
Published: September 2016

AbstractIonizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1–100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential.
Local and thalamic origins of correlated ongoing and sensory-evoked cortical activities
Authors: Cohen-Kashi Malina Katayun , Mohar Boaz , Rappaport Akiva N. , Lampl Ilan 
Published: September 2016

AbstractThalamic inputs of cells in sensory cortices are outnumbered by local connections. Thus, it was suggested that robust sensory response in layer 4 emerges due to synchronized thalamic activity. To investigate the role of both inputs in the generation of correlated cortical activities, we isolated the thalamic excitatory inputs of cortical cells by optogenetically silencing cortical firing. In anaesthetized mice, we measured the correlation between isolated thalamic synaptic inputs of simultaneously patched nearby layer 4 cells of the barrel cortex. Here we report that in contrast to correlated activity of excitatory synaptic inputs in the intact cortex, isolated thalamic inputs exhibit lower variability and asynchronous spontaneous and sensory-evoked inputs. These results are further supported in awake mice when we recorded the excitatory inputs of individual cortical cells simultaneously with the local field potential in a nearby site. Our results therefore indicate that cortical synchronization emerges by intracortical coupling.
Quantum dot spin coherence governed by a strained nuclear environment
Authors: Stockill R. , Le Gall C. , Matthiesen C. , Huthmacher L. , Clarke E. , Hugues M. , Atatüre M. 
Published: September 2016

AbstractThe interaction between a confined electron and the nuclei of an optically active quantum dot provides a uniquely rich manifestation of the central spin problem. Coherent qubit control combines with an ultrafast spin–photon interface to make these confined spins attractive candidates for quantum optical networks. Reaching the full potential of spin coherence has been hindered by the lack of knowledge of the key irreversible environment dynamics. Through all-optical Hahn echo decoupling we now recover the intrinsic coherence time set by the interaction with the inhomogeneously strained nuclear bath. The high-frequency nuclear dynamics are directly imprinted on the electron spin coherence, resulting in a dramatic jump of coherence times from few tens of nanoseconds to the microsecond regime between 2 and 3 T magnetic field and an exponential decay of coherence at high fields. These results reveal spin coherence can be improved by applying large magnetic fields and reducing strain inhomogeneity.
Relationships between pathology and crystal structure in breast calcifications: an in situ X-ray diffraction study in histological sections
Authors: Scott Robert , Stone Nicholas , Kendall Catherine , Geraki Kalotina , Rogers Keith 
Published: September 2016

AbstractCalcifications are not only one of the most important early diagnostic markers of breast cancer, but are also increasingly believed to aggravate the proliferation of cancer cells and invasion of surrounding tissue. Moreover, this influence appears to vary with calcification composition. Despite this, remarkably little is known about the composition and crystal structure of the most common type of breast calcifications, and how this differs between benign and malignant lesions. We sought to determine how the phase composition and crystallographic parameters within calcifications varies with pathology, using synchrotron X-ray diffraction. This is the first time crystallite size and lattice parameters have been measured in breast calcifications, and we found that these both parallel closely the changes in these parameters with age observed in fetal bone. We also discovered that these calcifications contain a small proportion of magnesium whitlockite, and that this proportion increases from benign to in situ to invasive cancer. When combined with other recent evidence on the effect of magnesium on hydroxyapatite precipitation, this suggests a mechanism explaining observations that carbonate levels within breast calcifications are lower in malignant specimens.