bluuebunny/crossref_metadata_2025_split huggingface dataset:
Global Attenuation in Spiral Galaxies in Optical and Infrared Bands
Authors: Kourkchi Ehsan , Tully R. Brent , Neill J. Don , Seibert Mark , Courtois Hélène M. , Dupuy Alexandra 
Published: October 2019

Abstract
The emerging light from a galaxy is under the influence of its own interstellar medium, as well as its spatial orientation. Considering a sample of 2239 local spiral galaxies in optical (Sloan Digital Sky Survey u, g, r, i, and z) and infrared bands (WISE W1, W1), we study the dependency of the global intrinsic attenuation in spiral galaxies on their morphologies, sizes, and spatial inclinations. Reddening is minimal at the extremes of low mass and gas depletion and maximal in galaxies that are relatively massive and metal-rich and still retain substantial gas reserves. A principal component constructed from observables that monitor galaxy mass, relative H i content to old stars, and infrared surface brightness is strongly correlated with the amplitude of obscuration. We determine both a parametric model for dust obscuration and a nonparametric model based on the Gaussian process formalism. An average dust attenuation curve is derived for wavelengths between 0.36 and 4.5 μm.
Constraints on the Galactic Inner Halo Assembly History from the Age Gradient of Blue Horizontal-branch Stars
Authors: Whitten Devin D. , Beers Timothy C. , Placco Vinicius M. , Santucci Rafael M. , Denissenkov Pavel , Tissera Patricia B. , Mejías Andrea , Hernitschek Nina , Carollo Daniela 
Published: October 2019

Abstract
We present an analysis of the relative age distribution of the Milky Way halo, based on samples of blue horizontal-branch (BHB) stars obtained from the Panoramic Survey Telescope and Rapid Response System and Galaxy Evolution Explorer photometry, as well a Sloan Digital Sky Survey spectroscopic sample. A machine-learning approach to the selection of BHB stars is developed, using support vector classification, with which we produce chronographic age maps of the Milky Way halo out to 40 kpc from the Galactic center. We identify a characteristic break in the relative age profiles of our BHB samples, corresponding to a Galactocentric radius of R
GC ∼ 14 kpc. Within the break radius, we find an age gradient of −63.4 ± 8.2 Myr kpc−1, which is significantly steeper than obtained by previous studies that did not discern between the inner- and outer-halo regions. The gradient in the relative age profile and the break radius signatures persist after correcting for the influence of metallicity on our spectroscopic calibration sample. We conclude that neither are due to the previously recognized metallicity gradient in the halo, as one passes from the inner-halo to the outer-halo region. Our results are consistent with a dissipational formation of the inner-halo population, involving a few relatively massive progenitor satellites, such as those proposed to account for the assembly of Gaia-Enceladus, which then merged with the inner halo of the Milky Way.
Counter-rotation and High-velocity Outflow in the Parsec-scale Molecular Torus of NGC 1068
Authors: Impellizzeri C. M. Violette , Gallimore Jack F. , Baum Stefi A. , Elitzur Moshe , Davies Richard , Lutz Dieter , Maiolino Roberto , Marconi Alessandro , Nikutta Robert , O’Dea Christopher P. , Sani Eleonora 
Published: October 2019

Abstract
We present 1.4 pc resolution observations of 256 GHz nuclear radio continuum and HCN (J = 3 → 2) in the molecular torus of NGC 1068. The integrated radio continuum emission has a flat spectrum consistent with free–free emission and resolves into an X-shaped structure resembling an edge-brightened bicone. HCN is detected in absorption against the continuum, and the absorption spectrum shows a pronounced blue wing that suggests a high-velocity molecular outflow with speeds reaching 450 km s−1. Analysis of the off-nucleus emission line kinematics and morphology reveals two nested, rotating disk components. The inner disk, inside r ∼ 1.2 pc, has kinematics that are consistent with the nearly edge-on, geometrically thin H2O megamaser disk in Keplerian rotation around a central mass of 1.66 × 107
M
⊙. The outer disk, which extends to ∼7 pc radius, counter-rotates relative to the inner disk. The rotation curve of the outer disk is consistent with rotation around the same central mass as the megamaser disk but in the opposite sense. The morphology of the molecular gas is asymmetric around the nuclear continuum source. We speculate that the outer disk formed from more recently introduced molecular gas falling out of the host galaxy or from a captured dwarf satellite galaxy. In NGC 1068, we find direct evidence that the molecular torus consists of counter-rotating and misaligned disks on parsec scales.
The Reliability of the Low-latency Estimation of Binary Neutron Star Chirp Mass
Authors: Biscoveanu Sylvia , Vitale Salvatore , Haster Carl-Johan 
Published: October 2019

Abstract
The LIGO and Virgo Collaborations currently conduct searches for gravitational waves from compact binary coalescences in real time. For promising candidate events, a sky map and distance estimation are released in low latency to facilitate their electromagnetic follow-up. Currently, no information is released about the masses of the compact objects. Recently, Margalit & Metzger suggested that knowledge of the chirp mass of the detected binary neutron stars could be useful to prioritize the electromagnetic follow-up effort, and urged the LIGO-Virgo collaboration to release chirp mass information in low latency. One might worry that low-latency searches for compact binaries make simplifying assumptions that could introduce biases in the mass parameters: neutron stars are treated as point particles with dimensionless spins below 0.05 perfectly aligned with the orbital angular momentum. Furthermore, the template bank used to search for them has a finite resolution. In this paper we show that none of these limitations can introduce chirp mass biases larger than ∼10−3 M
⊙. Even the total mass is usually accurately estimated, with biases smaller than 6%. The mass ratio and effective inspiral spins, on the other hand, can suffer from more severe biases.
CDF-S XT1 and XT2: White Dwarf Tidal Disruption Events by Intermediate-mass Black Holes?
Authors: Peng Zong-Kai , Yang Yi-Si , Shen Rong-Feng , Wang Ling-Jun , Zou Jin-Hang , Zhang Bin-Bin 
Published: October 2019

Abstract
Recently, two fast X-ray transients (XT1 and XT2) have been reported from the search in the Chandra Deep Field (CDF) data. Each transient shows an initial plateau lasting around hundreds to thousands of seconds followed by a rapid decay in the light curve. In particular, CDF-S XT2 is found to be associated with a galaxy at redshift z = 0.738 and was explained as a counterpart of a binary neutron-star merger event. In this Letter, motivated by the short duration and decay slopes of the two transients, we consider an alternative interpretation in which both events are accretion-driven flares from tidal disruption of white dwarfs by intermediate-mass black holes. We derive a theoretical model of the accretion rate history and find that it fits the observed X-ray light curves well. The extremely super-Eddington peak luminosity of XT2 can be explained by the beaming effect of the system, likely in the form of a jet.
Intraoperative Aberrometry Versus Preoperative Biometry for IOL Power Selection After Radial Keratotomy: A Prospective Study
Authors: Curado Sebastião Xavier , Hida Wilson Takashi , Vilar César Martins Cortez , Ordones Virgílio Luiz , Chaves Mário Augusto Pereira , Tzelikis Patrick Frensel 
Published: October 2019

PURPOSE:
To compare the accuracy of Optiwave Refractive Analysis (ORA) intraoperative aberrometry (Alcon Laboratories, Inc., Fort Worth, TX) with preoperative biometry in predicting residual refractive error after cataract surgery in eyes that underwent radial keratotomy.

METHODS:
This was a prospective consecutive case series of patients with cataract and prior radial keratotomy. Each patient underwent a preoperative intraocular lens (IOL) power calculation using partial coherence interferometry (IOLMaster version 5; Carl Zeiss Meditec, Jena, Germany). For each eye, the Barrett True-K formula was used to select an IOL targeting emmetropia. Residual refractive error was predicted preoperatively using the SRK/T, Hoffer Q, Haigis, and Holladay formulas 1 and 2, and the ORA intraoperatively. Between 8 and 12 weeks after cataract extraction with IOL implantation, the postoperative refraction was compared with the preoperative and intraoperative predictions.

RESULTS:

The study comprised 52 eyes of 34 patients. The median absolute errors associated with each method were as follows: Barrett True-K formula (0.34), ORA aberrometer (0.53), and SRK/T (0.54), Hoffer Q (0.51), Haigis (0.54), SRK/T (0.57), and Holladay formulas 1 and 2 (0.44) (
P
= .08). The proportion of patients within ±0.50 diopters of the predicted error was 63.5%, 48.1%, 44.2%, 48.1%, 53.8%, 36.5%, and 57.7%, respectively (
P
= .03). No statistically significant difference was observed in the number of eyes with hyperopic outcomes (
P
= .68).

CONCLUSIONS:
In eyes with prior radial keratotomy surgery, the ORA aberrometer performance was similar to the Barrett True-K formula and all of the other established formulas, with no significant difference between median absolute error and mean absolute error. The Barrett True-K formula produced significantly more eyes within ±0.50 diopters than the SRK/T, Hoffer Q, and Holladay 1 formulas.

[
J Refract Surg.
2019;35(10):656–661.]
FCX, an arylidene derivative, induces apoptosis in androgen receptor-selective prostate cancer cells
Authors: Prasanna Rajagopalan , Elbessoumy Ashraf A. , Chandramoorthy Harish C. , Dera Ayed , Al Fayi Majed 
Published: October 2019

Context:
Rational screening of arylidene derivatives for biological activities has resulted in many lead molecules with anticancer properties with effective therapeutic window.

Aims:
In the current study, FCX, an arylidene derivative, was screened for anticolon and prostate cancer activity.

Settings and Design:
Prostate and colon cancer cell lines were used to check the FCX effect on proliferation, apoptosis, and mechanism of drug action.

Subjects and Methods:
LNCaP, PC-3, HCT-8, and HT-29 cells were treated with various concentrations of the FCX. MTT assay was performed to check proliferation, propidium iodide and Hoechst dual staining for DNA fragmentation, and Annexin V binding assay for apoptosis, and cell cycle assay was done using flow cytometry. Functional androgen-mutated receptor cells were used mechanistic pathway elucidation.

Statistical Analysis Used:
A minimum of three individual replicates at different time periods were taken as mean value. The data were expressed in mean ± standard deviation. Student's t-test and one-way ANOVA were used to assess the statistical difference between the groups.

Results:
FCX inhibited proliferation of prostate cancer cell lines in a dose-dependent manner with more selectivity toward LNCaP cells. Nuclear fragmentation and dose-dependent increase in Annexin V-positive LNCaP cells revealed apoptosis. Cell cycle G2/M phase arrest along with sub-G0/G1 population augmented the antiproliferative observations. Addition of FCX in the presence of estradiol, testosterone, and dehydroepiandrosterone, LNCaP cells markedly caused a dose-dependent increase in cell proliferation indicating the compound activity to be facilitated through androgen receptor pathway.

Conclusions:
Together with the results, it is evident that FCX has a wide therapeutic window in the in vitro inhibition of the prostate cancer cells mediated by hormone-dependent effects.
Job stress and satisfaction in faculty of a teaching hospital in south India
Authors: Chichra A , Abhijnhan A , Tharyan P 
Published: October 2019

Background:
There are multiple economic, psychological, and physical consequences of high job stress, low job satisfaction and burnout in faculty of a teaching hospital in South India. Data from developing countries on these domains are sparse.

Materials and Methods:
In a cross-sectional study we assessed the prevalence and sources of perceived job stress, job satisfaction and burnout in faculty, as well as ways of coping with stress among consenting faculty of a large, private, charitable, teaching hospital in India using standardized, self-rated questionnaires.

Results:
A total of 304 respondents, 156 (51.3%) were Assistant Professors; 71 (23.4%) were Associate Professors, and 77 (25.3%) were Professors. The majority (175; 58%) were male, younger than 45 years (235; 76%) and from clinical departments (248; 81.5%) A third (96; 31%) reported high overall levels of perceived job stress. In multivariate analyses, age less than 45 years, designation as Assistant or Associate Professor, and working in a clinical department were associated with perceived high job stress; reporting high perceived job satisfaction was protective. Nearly two-thirds (217; 71.4%) of faculty reported high levels of job satisfaction. In multivariate analysis, age less than 45 years and reporting high job stress were associated with low perceived job satisfaction. Causes of stress and satisfaction differed by age, gender and designation. On the Maslach Burnout Inventory (MBI), 88 (29%) had high scores on the emotional exhaustion subscale, 63 (20.8%) had high scores on the depersonalization subscale, and 90 (29.7%) had low scores on the personal achievement subscales. High job stress and low job satisfaction were significantly associated with burnout on the three domains.

Conclusions:
High job stress and low job satisfaction were inversely related in this survey of medical faculty and were significantly associated with levels of burnout. The sources of job stress and job satisfaction identified provide insights that could inform formal institutional mechanisms to prevent burnout in doctors.
Experimental Investigations of Microwave Effects on Rock Breakage Using SEM Analysis
Authors: Teimoori Khashayar , Hassani Ferri , Sasmito Agus Pulung , Madiseh Ali Ghoreishi 
Published: October 2019

Preconditioning of hard rocks by microwave energy has recently been considered a potentially effective technology in mechanical rock breakage for civil and mining engineering. To obtain the amount of mechanical damage that a single-mode microwave treatment produces in rocks, it is necessary to analyze and evaluate the thermal cracking process by microwave heating at different power levels, exposure times, and distances from the antenna. The current study employs the scanning electron microscopy imaging technique to capture images from surfaces of irradiated rock specimens and to compare them with a nontreated specimen. To evaluate and quantify the amount of cracking (i.e. crack density, crack size, etc.) in a rock specimen after microwave irradiation with different microwave input operating parameters, the following steps were evaluated. First, several experiments of single-mode microwave treatments with different operating parameters were performed on rectangular specimens of basalt. Then, cylindrical core samples with a dimension of r = 0.5 cm, h = 2cm, were drilled from the center of the irradiated specimens and prepared for image processing. The results of the present study show that there are significant differences between the number of microcracks present in samples irradiated at different power levels and distances from the antenna. Also, longer exposure times result in more severe cracks.
SCALABLE MICROWAVE WASTE-TO-FUEL CONVERSION
Authors: Robinson Megan , Popovic Zoya 
Published: October 2019

This paper presents an efficiency study for scalable microwave waste management. When waste with carbon content is subjected to volume power densities on the order of 0.25W/cm3 at GHz frequencies, it converts to solid coke fuel with oil and gas bi-products that can further be processed for fuel, leaving no trace. For an efficient process, a well-controlled uniform RF field should be maintained in a non-uniform and time-variable material. We are developing a 2.45-GHz active microwave cavity with solid-state (GaN) spatially power combined sources for lower volumes, Fig.1. In the energy balance calculations, the input energy into the system consists of the waste chemical energy and the DC electrical energy used to obtain the RF power with an efficiency that can reach 70% for kW power levels. The efficiency of RF power conversion to heat in the waste mass is calculated from full-wave simulations for typical waste mixtures and ranges from 10 to 90% depending on the material and cavity filling. The output energy estimates are collected from various pyrolysis process descriptions, e.g. [1], with the total energy being that of the solid fuel (35MJ/kg) and oil caloric values, e.g. 40MJ/kg for plastics and about 10-15MJ/kg for nonplastics [2]. A byproduct is flue gas which can be converted to Syngas [3]. The total worse-case carbon footprint balance (0.3-3) calculations will be presented. Fig. 1. Block diagram of active microwave cavity for waste to fuel conversion. References D. Czajczyńska, “Potential of pyrolysis processes in the waste management sector,” Thermal Science and Engineering Progress, vol. 3, p. 171. Sept., 2017. J.A. Onwudili, “Composition of products from the pyrolysis of polyethylene and polystyrene in a closed batch reactor: effects of temperature and residence time,” Journal of Analytical and Applied Pyrolysis, vol. 86 p. 293–303. Nov., 2009. S. Chunshan, "Tri-reforming of methane: a novel concept for synthesis of industrially useful synthesis gas with desired H2/CO ratios using CO2 in flue gas of power plants without CO2 separation." Prepr. Pap.-Am. Chem. Soc., Div. Fuel Chem 49, no. 1 (2004): 128.
SELECTIVE FORMATION OF LINEAR ALPHA-OLEFINS VIA MICROWAVE CATALYTIC CRACKING OF LIQUID STRAIGHT-CHAIN ALKANES
Authors: Bolotov Vasiliy Alexandrovich , Tikhov Serguei Fedorovich , Valeev Konstantin Radikovich , Shamirzaev Vladimir Timurovich , Parmon Valentin Nikolaevich 
Published: October 2019

Linear even-carbon-number alpha-olefins (LAO) with four or more carbon atoms are important compounds of high demand in chemical industry as precursors of a wide range of value-added chemicals [1]. LAO are used as co-monomers for polyethylene production, for the production of alcohols (mainly in detergents and plasticizers) and for synthesis of polyalphaolefins (used in synthetic lubricants). Alpha-olefins (C4, C6, C8 and C10) are mainly used to produce poly(vinyl chloride) plasticizers, high-density and linear low-density polyethylene to impart the stress-crack resistance. C10–C14 alpha-olefins can be used to synthesize linear alkylbenzene sulfonates (synthetic detergents). A conventional route to produce alpha-olefins is oligomerization of ethylene. The process provides production of high quality alpha-olefins but is very costly. If not oligomerization, LAO can be produced by thermal cracking of waxy paraffins but the product is not pure and contains numerous internal olefins, dienes and paraffin impurities. The process is conducted in the vapor phase at relatively low cracking temperatures and needs rapid quenching to prevent side reactions such as isomerization or cyclization. In our previous work [2], we showed that the selectivity to alpha-olefins can be increased considerably via catalytic cracking of n-alkanes under selective MW heating of catalysts. In the present work, the general regularities of MW cracking of n-alkanes are presented. Porous ceramic matrix Al2O3/Al composites (ceramometals) and various carbon materials (CM) having high dielectric losses were studied as supports of the catalysts. MW cracking was conducted with n-C16H34 and n-C28H58. The influence particle size and surface morphology of ceramometals and CM on the structural and group composition of the products was studied. It was established that LAO (C2-C23) and n-alkanes (C2-C26) were the main cracking products under selective MW heating of the used supports. The quantitative analysis of the products demonstrated that the liquid-phase process is more selective to alpha-olefins at the MW catalytic cracking than at the convectional thermal cracking. Silica modification of the surface of CM was shown to suppress spark discharge (usually observed at MW heating of CM); hence, the thermal cleavage of C-C bonds on the CM surface but not in the plasma discharge contributes the most to the formation of radicals. It was shown that the selectivity to liquid alpha-olefin could be more than 85 % under MW heating of cermets in region of the E - field node and decrease considerably in the region of H - field node.
PLANE WAVE IRRADIATION OF A LAYERED SYSTEM: RESONANCE-BASED CONTROL OVER THERMAL RUNAWAY
Authors: Mohekar Ajit , Tilley Burt , Yakovlev Vadim 
Published: October 2019

The loss factor of a material is a key characteristic behind heat generation during EM heating. For typical ceramics, the loss factor increases exponentially with temperature potentially initiating thermal runaway which can damage the material through melting or cracking. Equilibrium of EM heating can be represented by a parametric plot of the average steady-state temperature as function of the applied power that is known as a power response curve. In a layered structure, for wavelengths of the incident wave that are much larger than the layer’s thickness, the power response curve is an S-shaped bifurcation diagram (or S-curve). Stable temperatures are low at the lower branch of the S-curve and may be very high (up to ~2000 K) at the upper branch. The recent analytical and numerical models show that, for a triple (lossless-lossy-lossless) layered system, when thickness of the structure is comparable with the wavelength, an electric field resonance can be achieved in the lossy layer. This resonance causes the S-curve to acquire another (middle) stable branch and become a double S-curve. That suggests that temperatures during thermal runaway may be controlled by the field resonance. However, these models assume two-side symmetric irradiation. In this paper, we show that the resonance producing a double S-curve can be achieved in a more practical scenario with one-side irradiation: in the system with a metal plate the resonance is achieve by choosing layer's thickness and triggering a constructive interference of the incident and reflected waves. A series of double S-curves computed with COMSOL Multiphysics are analyzed, and practical ways of controlling thermal runaway in EM heating of layered structures are discussed.