bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C7H in Molecular Clouds
Authors: Araki Mitsunori , Takano Shuro , Sakai Nami , Yamamoto Satoshi , Oyama Takahiro , Kuze Nobuhiko , Tsukiyama Koichi 
Published: September 2017

Abstract
Long carbon-chain molecules were searched for toward the low-mass star-forming region L1527, which is a prototypical source of warm carbon-chain chemistry (WCCC), using the 100 m Green Bank Telescope. Long carbon-chain molecules, C7H (2Π1/2), C6H (2Π3/2 and 2Π1/2), CH3C4H, and C6H2 (cumulene carbene, CCCCCCH2), and cyclic species of C3H and C3H2O were detected. In particular, C7H was detected for the first time in molecular clouds. The column density of C7H is determined to be 6 × 1010 cm−2. The column densities of the carbon-chain molecules including CH3C4H and C6H in L1527 relative to those in the starless dark cloud Taurus Molecular Cloud-1 Cyanopolyyne Peak (TMC-1 CP) tend to be systematically lower for long carbon-chain lengths. However, the column densities of C7H and C6H2 do not follow this trend and are found to be relatively abundant in L1527. This result implies that these long carbon-chain molecules are remnants of the cold starless phase. The results—that both the remnants and WCCC products are observed toward L1527—are consistent with the suggestion that the protostar can also be born in the parent core at a relatively early stage in the chemical evolution.
Can the Discrepancy between Locally and Globally Derived Neutral Hydrogen Mass Functions be Explained by a Varying Value of M ⋆?
Authors: Minchin Robert F. 
Published: September 2017

Abstract
I investigate whether it is possible to reconcile the recent Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) observation that the neutral hydrogen mass function (HIMF) across different galactic densities has the same, non-flat, faint-end slope, with observations of isolated galaxies and many galaxy groups that show their HIMFs to have flat faint-end slopes. I find that a fairly simple model in which the position of the knee in the mass function of each individual group is allowed to vary is able to account for both of these observations. If this model reflects reality, the ALFALFA results point to an interesting “conspiracy” whereby the differing group HIMFs always sum up to form global HIMFs with the same faint-end slope in different environments. More generally, this result implies that global environmental HIMFs do not necessarily reflect the HIMFs in individual groups belonging to that environment and cannot be used to directly measure variations in group-specific HIMFs with environment.
Convergence of the Critical Cooling Rate for Protoplanetary Disk Fragmentation Achieved: The Key Role of Numerical Dissipation of Angular Momentum
Authors: Deng Hongping , Mayer Lucio , Meru Farzana 
Published: September 2017

Abstract
We carry out simulations of gravitationally unstable disks using smoothed particle hydrodynamics (SPH) and the novel Lagrangian meshless finite mass (MFM) scheme in the GIZMO code. Our aim is to understand the cause of the nonconvergence of the cooling boundary for fragmentation reported in the literature. We run SPH simulations with two different artificial viscosity implementations and compare them with MFM, which does not employ any artificial viscosity. With MFM we demonstrate convergence of the critical cooling timescale for fragmentation at

. Nonconvergence persists in SPH codes. We show how the nonconvergence problem is caused by artificial fragmentation triggered by excessive dissipation of angular momentum in domains with large velocity derivatives. With increased resolution, such domains become more prominent. Vorticity lags behind density, due to numerical viscous dissipation in these regions, promoting collapse with longer cooling times. Such effect is shown to be dominant over the competing tendency of artificial viscosity to diminish with increasing resolution. When the initial conditions are first relaxed for several orbits, the flow is more regular, with lower shear and vorticity in nonaxisymmetric regions, aiding convergence. Yet MFM is the only method that converges exactly. Our findings are of general interest, as numerical dissipation via artificial viscosity or advection errors can also occur in grid-based codes. Indeed, for the FARGO code values of

significantly higher than our converged estimate have been reported in the literature. Finally, we discuss implications for giant planet formation via disk instability.
The Evaporation Valley in the Kepler Planets
Authors: Owen James E. , Wu Yanqin 
Published: September 2017

Abstract
A new piece of evidence supporting the photoevaporation-driven evolution model for low-mass, close-in exoplanets was recently presented by the California–Kepler Survey. The radius distribution of the Kepler planets is shown to be bimodal, with a “valley” separating two peaks at 1.3 and 2.6 R
⊕. Such an “evaporation valley” had been predicted by numerical models previously. Here, we develop a minimal model to demonstrate that this valley results from the following fact: the timescale for envelope erosion is the longest for those planets with hydrogen/helium-rich envelopes that, while only a few percent in weight, double its radius. The timescale falls for envelopes lighter than this because the planet’s radius remains largely constant for tenuous envelopes. The timescale also drops for heavier envelopes because the planet swells up faster than the addition of envelope mass. Photoevaporation therefore herds planets into either bare cores (∼1.3 R
⊕), or those with double the core’s radius (∼2.6 R
⊕). This process mostly occurs during the first 100 Myr when the stars’ high-energy fluxes are high and nearly constant. The observed radius distribution further requires the Kepler planets to be clustered around 3 M
⊕ in mass, born with H/He envelopes more than a few percent in mass, and that their cores are similar to the Earth in composition. Such envelopes must have been accreted before the dispersal of the gas disks, while the core composition indicates formation inside the ice line. Lastly, the photoevaporation model fails to account for bare planets beyond ∼30–60 days; if these planets are abundant, they may point to a significant second channel for planet formation, resembling the solar system terrestrial planets.
Global Energetics of Solar Flares. VI. Refined Energetics of Coronal Mass Ejections
Authors: Aschwanden Markus J. 
Published: September 2017

Abstract
In this study, we refine the coronal mass ejection (CME) model that was presented in an earlier study of the global energetics of solar flares and associated CMEs and apply it to all (860) GOES M- and X-class flare events observed during the first seven years (2010–2016) of the Solar Dynamics Observatory (SDO) mission. The model refinements include (1) the CME geometry in terms of a 3D volume undergoing self-similar adiabatic expansion, (2) the solar gravitational deceleration during the propagation of the CME, which discriminates between eruptive and confined CMEs, (3) a self-consistent relationship between the CME center-of-mass motion detected during EUV dimming and the leading-edge motion observed in white-light coronagraphs, (4) the equipartition of the CME’s kinetic and thermal energies, and (5) the Rosner–Tucker–Vaiana scaling law. The refined CME model is entirely based on EUV-dimming observations (using Atmospheric Imager Assembly (AIA)/SDO data) and complements the traditional white-light scattering model (using Large-Angle and Spectrometric Coronagraph Experiment (LASCO)/Solar and Heliospheric Observatory data), and both models are independently capable of determining fundamental CME parameters. Comparing the two methods, we find that (1) LASCO is less sensitive than AIA in detecting CMEs (in 24% of the cases), (2) CME masses below

g are underestimated by LASCO, (3) AIA and LASCO masses, speeds, and energies agree closely in the statistical mean after the elimination of outliers, and (4) the CME parameters speed v, emission measure-weighted flare peak temperature T

e
, and length scale L are consistent with the following scaling laws:

,

, and

.
Discovery of Two New Hypervelocity Stars from the LAMOST Spectroscopic Surveys
Authors: Huang Y. , Liu X.-W. , Zhang H.-W. , Chen B.-Q. , Xiang M.-S. , Wang C. , Yuan H.-B. , Tian Z.-J. , Li Y.-B. , Wang B. 
Published: September 2017

Abstract
We report the discovery of two new unbound hypervelocity stars (HVSs) from the LAMOST spectroscopic surveys. They are, respectively, a B2V-type star of ∼7 M
⊙ with a Galactic rest-frame radial velocity of 502 km s−1 at a Galactocentric radius of ∼21 kpc and a B7V-type star of ∼4 M
⊙ with a Galactic rest-frame radial velocity of 408 km s−1 at a Galactocentric radius of ∼30 kpc. The origins of the two HVSs are not clear given their currently poorly measured proper motions. However, the future data releases of Gaia should provide proper motion measurements accurate enough to solve this problem. The ongoing LAMOST spectroscopic surveys are expected to yield more HVSs to form a statistical sample, providing vital constraints on understanding the nature of HVSs and their ejection mechanisms.
Epicardial Adipose Tissue Volume and Cardiovascular Risk Indices among Asymptomatic Women with and without HIV
Authors: Srinivasa Suman , Lu Michael T , Fitch Kathleen V , Hallett Travis R , O'Malley Timothy K , Stone Lauren A , Martin Amanda , Coromilas Alexandra J , Burdo Tricia H , Triant Virginia A , Lo Janet , Looby Sara E , Neilan Tomas G , Zanni Markella V 
Published: September 2017

Background Mechanisms underlying the heightened myocardial infarction risk among HIV-infected women (versus non-HIV-infected women) remain unclear. Our objectives were to assess epicardial adipose tissue (EAT) volume and its associations among asymptomatic women with and without HIV. Methods A total of 55 HIV-infected and 27 non-HIV-infected women without known cardiovascular disease who underwent cardiac CT and metabolic/immune phenotyping were included. EAT volume derived from CT was compared among women with and without HIV, and within-group EAT associations were assessed. Next, immune and atherosclerotic plaque parameters were compared among groups stratified by HIV serostatus and high/low EAT (defined in reference to median EAT for each serostatus group). Results Asymptomatic HIV-infected women and age-matched non-HIV-infected women with comparable mean body mass index (28 ±1 versus 29 ±1 kg/m2) had similar median (IQR) volumes of EAT (54 [41–79] versus 65 [41–78] cm3; P>0.05); however, different within-group associations were noted. Markers of monocyte activation/arterial inflammation differed by HIV serostatus/EAT volume subgroup (CXCL10 [ P=0.02], sCD163 [ P=0.004], sCD14 [ P=0.03], Lp-PLA2 [ P=0.04]; P for overall ANOVA) and were highest among HIV-infected women with excess EAT (versus HIV-infected women without excess EAT, non-HIV-infected women with excess EAT and non-HIV-infected women without excess EAT). The percentage of segments with non-calcified coronary plaque also differed by HIV serostatus/EAT volume subgroup and was highest among HIV-infected women with excess EAT. Conclusions Asymptomatic women with and without HIV have similar volumes of EAT, but drivers of EAT may differ between groups. HIV-infected women with excess EAT have highest-level immune activation and the highest percentage of non-calcified plaque. Future studies are needed to determine whether EAT contributes pathogenetically to HIV-associated cardiovascular disease in women.
Tauromachies et temporalités : un système de transformations entre sport et art du spectacle
Authors: Saumade Frédéric 
Published: September 2017

À partir d’une mise au point théorique sur les similitudes et différences formelles entre le « système des sports » et les spectacles tauromachiques, mêmement caractérisés par un processus de rationalisation du rapport au temps, l’auteur, suivant une méthodologie structuraliste et comparative fondée sur une ethnographie localisée entre l’Europe du sud-ouest et l’Amérique du nord, met en exergue la relativité culturelle des jeux d’arènes. Il montre que les principes de temporalité observés dans les différents types de spectacles, de la corrida espagnole au rodéo américain, avec ou sans mise à mort, se résolvent en un quadrant, soit une structure de corrélations et d’oppositions à quatre termes qui donne toute sa cohérence à un mode de performance paradoxal, oscillant constamment entre sport, cirque, tragédie, comédie et gestion du cycle de la vie et de la mort par la confrontation de l’humain et de ses animaux d’élevage.
Circulating CD34+ Cell Count is Associated with Extent of Subclinical Atherosclerosis in Asymptomatic Amish Men, Independent of 10-Year Framingham Risk
Authors: Bielak Lawrence F. , Horenstein Richard B. , Ryan Kathleen A. , Sheedy Patrick F. , Rumberger John A. , Tanner Keith , Post Wendy , Mitchell Braxton D. , Shuldiner Alan R. , Peyser Patricia A. 
Published: September 2017

Background Bone-marrow derived progenitor cells (PCs) may play a role in maintaining vascular health by actively repairing damaged endothelium. The purpose of this study in asymptomatic Old Order Amish men (n = 90) without hypertension or diabetes was to determine if PC count, as determined by CD34+ cell count in peripheral blood, was associated with 10-year risk of cardiovascular disease (CVD) and measures of subclinical atherosclerosis. Methods and Results CD34+ cell count by fluorescence-activated cell sorting, coronary artery calcification (CAC) by electron beam computed tomography, and CVD risk factors were obtained. Carotid intimal-medial thickness (CIMT) also was obtained in a subset of 57 men. After adjusting for 10-year CVD risk, CD34+ cell count was significantly associated with CAC quantity ( p =0.03) and CIMT ( p < 0.0001). A 1-unit increase in natural-log transformed CD34+ cell count was associated with an estimated 55.2% decrease (95% CI: −77.8% to −9.3%) in CAC quantity and an estimated 14.3% decrease (95% CI: −20.1% to −8.1%) in CIMT. Conclusions Increased CD34+ cell count was associated with a decrease in extent of subclinical atherosclerosis in multiple arterial beds, independent of 10-year CVD risk. Further investigations of associations of CD34+ cell count with subclinical atherosclerosis in asymptomatic individuals could provide mechanistic insights into the atherosclerotic process.
The Threshold of Admission Glycemia as a Predictor of Adverse Events in Diabetic and Non-Diabetic Patients with Acute Coronary Syndrome
Authors: Garadah Taysir S. , Kassab Salah , Al-Shboul Qasim M. , Alawadi Abdulhai 
Published: September 2017

Recent studies indicated a high prevalence of hyperglycemia in non-diabetic patients presenting with acute coronary syndrome (ACS). However, the threshold of admission glucose (AG) as a predictor of adverse events in ACS is unclear. Objective The aim of this study was to assess the threshold of admission glucose (AG) as a predictor of adverse events including Major Acute Cardiac Events (MACE) and mortality, during the first week of admitting patients presenting with ACS. Material and Methods The data of 551 patients with ACS were extracted and evaluated. Patients were stratified according to their blood glucose on admission into three groups: group 1: <7 mmol/L (n = 200, 36.3%) and group 2: >7 mmol/L and <15 mmol/L (n = 178, 32.3%) and group 3: ≥15 mmol/L (n = 173, 31.4%). Stress hyperglycemia was arbitrarily defined as AG levels > 7 mmol/L (group 2 and 3). Patients with ACS were sub-divided into two groups: patients with unstable angina (UA, n = 285) and those with ST segment elevation myocardial Infarction (STEMI, n = 266) and data were analyzed separately using multiple regression analysis. Results The mean age of patients was 59.7 ± 14.8 years and 63% were males. The overall mortality in the population was 8.5% (5.4% in STEMI and 3.1% in UA) patients. In STEMI patients, the odds ratio of stress hyperglycemia as predictor of mortality in group 3 compared with group 1 was 3.3 (CI 0.99-10.98, P < 0.05), while in group 2 compared with group 1 was 2.4 (CI: 0.75-8.07, P = 0.065) after adjustment for age and sex. Similarly, in UA patients, the odds ratio of stress hyperglycemia in group 3 compared with group 1 was 2.7 (CI 0.37-18.98, P < 0.05), while in group 2 compared with group 1 was 2.4 (CI: 0.4-15.2, P = 0.344) after adjustment for age and sex. The incidence of more than 2 MACE in both STEMI and UA patients was higher in group 3 compared with the other two groups. Regression analysis showed that history of DM, high level of LDL cholesterol, high level of HbA1c, and anterior infarction were significant predictors of adverse events while other risk factors such as BMI, history of hypertension and smoking were of no significance. Conclusion This study indicates that the stress hyperglycemia on admission is a powerful predictor of increased major adverse events and hospital mortality in patients with acute coronary syndrome.
Stress Cardiomyopathy (Takotsubo Cardiomyopathy)
Authors: Khouri Samer , Imran Naser 
Published: September 2017

Background Due to the rise in the number of reports of stress cardiomyopathy in the literature, awareness of this condition is increasing. Although different names have been used to describe this condition, the similarities in clinical, electrocardiographic, echocardiographic and angiographic features suggest that they represent the same spectrum of diseases with different underlying causes. The pathophysiology of stress cardiomyopathy remains controversial. Methods We describe a series of four cases of stress cardiomyopathy admitted to our institution over a period of six months with different presentations, but similar clinical course, EKG, echocardiographic, and catheterization findings. The ages ranged from 22 to 81 years; all four females. All showed characteristic wall motion abnormalities by imaging in the absence of significant coronary artery disease, with spontaneous recovery of left ventricular function with conservative therapy. Results Although the patients presented with different clinical scenarios, all four showed characteristic features of stress cardiomyopathy suggesting that the pathophysiology affecting the myocardium was the same. We present a review of the literature with a discussion of the history of this condition, characteristic clinical features, and diagnostic criteria used in the past as well as the suggested pathophysiology of this condition. Conclusion Stress cardiomyopathy is an underdiagnosed reversible cardiomyopathy triggered by severe emotional or physical stress. It represents a spectrum of conditions with reversible severe left ventricular systolic dysfunction that includes neurogenic cardiomyopathy. It is not confined to the Japanese population and can affect people of any ethnic background or nationality.
Effects of Nebivolol on Endothelial Function and Exercise Parameters in Patients with Slow Coronary Flow
Authors: Tiryakioglu Selma , Tiryakioglu Osman , Ari Hasan , Basel Mehmet C. , Bozat Tahsin 
Published: September 2017

Objective Earlier studies have reported that a decrease in exercise capacity might indicate endothelial dysfunction. However, the effects of improvement of endothelial functions on exercise capacity have not been evaluated. The aim of the present study is to investigate the effects of nebivolol on flow-mediated dilatation (FMD), and on the exercise capacities of the patients with slow coronary flow (SCF). Methods The study population included 25 subjects with SCF (Group 1) documented by the thrombolysis in myocardial infarction (TIMI) frame count, and 25 control group (Group 2) subjects with normal coronary angiography, for a total of 50 subjects who underwent coronary angiography due to several indications and had no coronary lesion. The TIMI frame count (TFC) values of the subjects in Group I for left anterior descending artery, right coronary, and circumflex coronary artery were 61.8 ± 30.6, 37.2 ± 17.4, and 34.6 ± 17.4, respectively. All the subjects received nebivolol 5 mg/day. Results At the end of the first month of FMD, the mean exercise duration (MED) and the Duke Scores of the patients with SCF were significantly higher than the baseline values. However, the values by the sixth month did not differ from that at the first month. Although a numerical improvement compared to the baseline values was observed for the subjects in Group 2 by the measurements at the end of the first and the sixth month, this difference was not statistically significant. Conclusions Nebivolol treatment increases FMD in the subjects with SCF. The difference in the exercise parameters of these subjects is particularly dramatic, and such an outcome may indirectly indicate long-term improvement in endothelial function.
Point-of-Care, Ultraportable Echocardiography Predicts Diuretic Response in Patients Admitted with Acute Decompensated Heart Failure
Authors: Krishnan Dena K. , Pawlaczyk Barbara , McCullough Peter A. , Enright Susan , Kunadi Arvind , Vanhecke Thomas E. 
Published: September 2017

Background Routine management of patients with acute decompensated heart failure (ADHF) requires careful attentiveness to fluid status and diuretic treatment efficacy. New advances in ultrasound have made ultraportable echocardiography (UE) available to physicians for point-of-care use. The purpose of this study is to explore physiologic measures of intravascular fluid volume derived from UE and explore predictors of diuretic response in ADHF. Methods Various echocardiography imaging measurements, particularly diameter and collapse of inferior vena cava (IVC), were collected from 77 patients admitted with a primary diagnosis of ADHF. Patients were divided into two groups based on whether or not they achieved a net negative fluid output of 3 L within 48 hours. The demographic information, serum laboratory markers, and physical characteristics of the subjects were obtained to correlate with daily ultrasound measurements. Univariate and multivariate analyses were used to compare diuretic “responders” to “nonresponders.” Results A negative change in the IVC diameter at 48 hours was robust in prediction of diuretic response. For every 1 mm decrease in the IVC diameter at 48 hours, there was an odds ratio of 1.62 (95% CI: 1.20-2.19) for responding to diuretic therapy independent of other variables including baseline renal filtration function and blood B-type natriuretic peptide. Conclusion Assessment of central venous pressure as a proxy for passive renal congestion independently predicts initial diuretic response in ADHF. Future research is needed to further understand the individual variation in response to loop diuresis and to identify optimal treatment approaches that utilize anatomic and physiologic measures such as venous ultrasound.