bluuebunny/crossref_metadata_2025_split huggingface dataset:
ECOLOGICAL FACTORS INFLUENCE ON THE EARLY ONTOGENESIS AND NUMBER OF SO-IUY MULLET (PLANILIZA HAEMATOCHEILA) IN THE SEA OF AZOV
Authors: Kozhurin Efim , Bully Liubov , Gubanov Evgeny 
Published: June 2020

In the article, an analysis of so-iuy mullet (Planiliza haematocheila) natural
reproduction conditions was performed in the Sea of Azov over the past 17 years.
The optimal and critical temperatures and salinity of the water were determined
for the effective spawning of so-iuy mullet as well as the influence of these factors
on its early ontogenesis, the dependence of the migration periods and spawning
of producers. An earlier spawning was observed in estuaries and bays.
PENGGUNAAN METODE EXPONENTIAL SMOOTHING UNTUK PERAMALAN PENJUALAN PRODUK GALVALUM (STUDI KASUS PADA TOKO ISTANA GALVALUM JEMBER)
Authors: Hotima Siti Husnul , Damara Deva 
Published: June 2020

Penelitian ini bertujuan untuk menghitung metode Exponential Smoothing dengan alpha 0,1 0,5 0,9 dalam meramalkan penjualan untuk periode selanjutnya. Penelitian ini merupakan penelitian kuantitatif dengan pendekatan deskriptif yang menggunakan data sekunder yaitu data penjualan Toko Istana Galvalum Jember mulai Bulan Oktober 2017 sampai September 2018. Hasil yang didapat dari penelitian ini antara lain hasil peramalan untuk produk Kanal C 1 mm yaitu menggunakan metode menggunakan metode Exponential Smoothing dengan alpha 0.9 dengan hasil peramalan untuk bulan Oktober 2018 sebesar 1006 unit. Hasil peramalan produk Kanal C 0,75 mm yaitu menggunakan metode Exponential Smoothing dengan alpha 0.9 dengan hasil peramalan untuk bulan Oktober 2018 sebesar 6547 unit. Hasil peramalan produk Kanal C 0,6 mm yaitu menggunakan metode Exponential Smoothing dengan alpha 0.1 dengan hasil peramalan untuk bulan Oktober 2018 sebesar 1564 unit. Hasil peramalan produk Reng yaitu menggunakan metode Exponential Smoothing dengan alpha 0.9 dengan hasil peramalan untuk bulan Oktober 2018 sebesar 15066 unit. Hasil peramalan produk Baut Skrup yaitu menggunakan metode Exponential Smoothing dengan alpha 0.5 dengan hasil peramalan untuk bulan Oktober 2018 sebesar 112982 unit.Keismpulan penelitian ini adalah peramalan yang memiliki nilai eror yang cukup rendah dan akurasi yang cukup baik dapat digunakan sebagai bahan pertimbangan dalam perencanaan pengadaan barang.
Prescription Errors Still a Challenge in Pakistan - A Cross-Sectional Study from Central Punjab, Pakistan
Authors: Obaid Hafiz , Sohaib Ahmed Umer , Munir Abu Bakar , Akbar Jamshaid , Zaman Muhammad Qamar-uz , Amjad Muhammad Arslan , Ahmad Sharjeel 
Published: June 2020

Objective: To evaluate the prescription writing pattern and errors in prescriptions at different health care units of Central Punjab, Pakistan.
Methods: A descriptive cross-sectional study design was adopted to conduct the present study. Data collection was done for a period of one month i.e. March 2018 from selected community pharmacies of five different cities of Central Punjab, Pakistan. Patients were approached irrespective of age and gender and data was recorded on a pre-designed Performa. The total sample size was 750 (150 prescriptions from each pharmacy). SPSS (Statistical Program for Social Sciences, version 20.0) was used for statistical analysis of data.
Results: Out of 750 prescriptions, 662 prescriptions were included in final analysis. Patient name was found written in almost all prescriptions 660 (99.7%) while physician name was missing on 519 (78.4%). Healthcare provider registration number and qualification were not on 654 (98.8%) and 527 (79.6%) prescriptions respectively. Poly-pharmacy was observed in 103 (16%) prescriptions and no prescription was found with generic name.
Conclusion: The study results highlighted the imperative need to devise policies that should be regulated and implemented by the healthcare authorities to make our prescriptions in line with the prescribed guidelines.
Sources of Bipolar Outflows and Model Challenges for the Egg Nebula
Authors: Dinh-V-Trung  , Lim Jeremy , Ohyama Youichi 
Published: June 2020

Abstract
The striking features of the Egg Nebula—searchlight beams that illuminate a pair of bipolar lobes, quadrupolar outflows, and arcs imprinted on an expanding spherical envelope—have long defied a coherent explanation. Here we present images at high angular resolutions of emission from dust and dense molecular gas in the nebula. Away from the systemic velocity, the molecular gas primarily traces the walls of the bipolar lobes, where bipolar outflows collide with the envelope ejected by the progenitor AGB star. At and close to the systemic velocity, both the molecular gas and dust trace the walls of a cylindrical channel swept aside by these bipolar outflows; in addition, the dust also traces a channel orthogonal to the bipolar lobes, swept aside by the orthogonal set of bipolar outflows. Close to the center, the dense gas traces an expanding spherical shell, corresponding to a very dense final puff from the progenitor AGB star. The center of this shell lies within the channel aligned with the optical lobes but is displaced to the south of the channel orthogonal to these lobes, and it closely coincides with the illumination center of the nebula (location of post-AGB star), as well as the expansion center of the bipolar lobes. We highlight difficulties faced by models whereby a binary companion both induces arcs in the wind of the progenitor AGB star and gives rise to the quadrupolar outflows. Instead, we suggest that the addition of a second companion, thus forming a triple-star system, can naturally produce all the features seen.
Testing Rotating Regular Metrics as Candidates for Astrophysical Black Holes
Authors: Kumar Rahul , Kumar Amit , Ghosh Sushant G. 
Published: June 2020

Abstract
The Event Horizon Telescope, a global submillimeter wavelength very long baseline interferometry array, produced the first image of supermassive black hole M87* showing a ring of diameter θ

d
= 42 ± 3 μas, inferred a black hole mass of M = (6.5 ± 0.7) × 109
M
⊙, and allowed us to investigate the nature of strong-field gravity. The observed image is consistent with the shadow of a Kerr black hole, which according to the Kerr hypothesis describes the background spacetimes of all astrophysical black holes. The hypothesis, a strong-field prediction of general relativity, may be violated in the modified theories of gravity that admit non-Kerr black holes. Here, we use the black hole shadow to investigate the constraints when rotating regular black holes (non-Kerr) can be considered as astrophysical black hole candidates, paying attention to three leading regular black hole models with additional parameters g related to nonlinear electrodynamics charge. Our interesting results based on the systematic bias analysis are that rotating regular black holes shadows may or may not capture Kerr black hole shadows, depending on the values of the parameter g. Indeed, the shadows of Bardeen black holes (g ≲ 0.26M), Hayward black holes (g ≲ 0.65M) and non-singular black holes (g ≲ 0.25M) are indistinguishable from Kerr black hole shadows within the current observational uncertainties, and thereby they can be strong viable candidates for the astrophysical black holes. Whereas Bardeen black holes (g ≤ 0.30182M), Hayward black holes (g ≤ 0.73627M), and non-singular black holes (g ≤ 0.30461M), within the 1σ region for θ

d
= 39 μas, are consistent with the observed angular diameter of M87*.
HST Survey of the Orion Nebula Cluster in the H2O 1.4 μm Absorption Band. III. The Population of Substellar Binary Companions
Authors: Strampelli Giovanni M. , Aguilar Jonathan , Pueyo Laurent , Aparicio Antonio , Gennaro Mario , Ubeda Leonardo , Robberto Massimo 
Published: June 2020

Abstract
We present new results concerning the substellar binary population in the Orion Nebula Cluster (ONC). Using the Karhunen–Loève Image Projection algorithm, we have reprocessed images taken with the IR channel of the Wide Field Camera 3 mounted on the Hubble Space Telescope to unveil faint, close companions in the wings of the stellar point-spread functions. Starting with a sample of 1392 bona fide unsaturated cluster members, we detect 39 close-pair cluster candidates with separation 0.″16–0.″77. The primary masses span a range M

p
∼ 0.015–1.27 M
☉, whereas for the companions we derive M

c
∼ 0.004–0.54 M
☉. Of these 39 binary systems, 18 were already known, while the remaining 21 are new detections. Correcting for completeness and combining our catalog with previously detected ONC binaries, we obtain an overall binary fraction of 11.5% ± 0.9%. Compared to other star-forming regions, our multiplicity function is ∼2 times smaller than, for example, Taurus, while compared to the binaries in the field we obtain comparable values. We analyze the mass functions of the binaries, finding differences between the mass distributions of binaries and single stars and between primary and companion mass distributions. The mass ratio shows a bottom-heavy distribution with median value M

c
/M

p
∼ 0.25. Overall, our results suggest that ONC binaries may represent a template for the typical population of field binaries, supporting the hypothesis that the ONC may be regarded as a most typical star-forming region in the Milky Way.
Very Long Baseline Astrometry of PSR J1012+5307 and its Implications on Alternative Theories of Gravity
Authors: Ding Hao , Deller Adam T. , Freire Paulo , Kaplan David L. , W. Lazio T. Joseph , Shannon Ryan , Stappers Benjamin 
Published: June 2020

Abstract
PSR J1012+5307, a millisecond pulsar in orbit with a helium white dwarf (WD), has been timed with high precision for about 25 yr. One of the main objectives of this long-term timing is to use the large asymmetry in gravitational binding energy between the neutron star and the WD to test gravitational theories. Such tests, however, will be eventually limited by the accuracy of the distance to the pulsar. Here, we present very long baseline interferometry (VLBI) astrometry results spanning approximately 2.5 yr for PSR J1012+5307, obtained with the Very Long Baseline Array as part of the

project. These provide the first proper motion and absolute position for PSR J1012+5307 measured in a quasi-inertial reference frame. From the VLBI results, we measure a distance of

kpc (all the estimates presented in the abstract are at 68% confidence) for PSR J1012+5307, which is the most precise obtained to date. Using the new distance, we improve the uncertainty of measurements of the unmodeled contributions to orbital period decay, which, combined with three other pulsars, places new constraints on the coupling constant for dipole gravitational radiation

and the fractional time derivative of Newton’s gravitational constant

in the local universe. As the uncertainties of the observed decays of orbital period for the four leading pulsar-WD systems become negligible in ≈10 yr, the uncertainties for

and κ

D
will be improved to ≤1.5 × 10−13 yr−1 and ≤1.0 × 10−4, respectively, predominantly limited by the distance uncertainties.
The Three Young Nuclear Super Star Clusters in NGC 5253
Authors: Smith Linda J. , Bajaj Varun , Ryon Jenna , Sabbi Elena 
Published: June 2020

Abstract
The blue compact dwarf galaxy NGC 5253 hosts a very young central starburst. The center contains intense radio thermal emission from a massive ultracompact H ii region (or supernebula) and two massive and very young super star clusters (SSCs), which are seen at optical and infrared wavelengths. The spatial correspondence between these three objects over an area of

is very uncertain, and it is usually assumed that one of the optically detected SSCs coincides with the supernebula. Using the Gaia Data Release 2 catalog, we improve the absolute astrometry of Hubble Space Telescope ultraviolet, optical, and infrared images by a factor of ∼10 and match them to the radio observations with an accuracy of 10–20 mas. We find that there are three SSCs at the center of NGC 5253. At optical wavelengths, the two SSCs lie on either side of the supernebula, which coincides with a highly obscured region. In the infrared, all three SSCs are seen with the supernebula dominating at the longest wavelengths. We examine the properties of the SSCs, which have ages of ∼1 Myr, are very compact (

pc), and are separated by projected distances of only 1.5 and 5.8 pc. It seems likely that they will merge and may form the building blocks for nuclear star clusters.
Discovery of a Universal Correlation for Long and Short GRBs and Its Application for the Study of Luminosity Function and Formation Rate
Authors: Guo Qi , Wei Da-Ming , Wang Yuan-Zhu , Jin Zhi-Ping 
Published: June 2020

Abstract
Gamma-ray bursts (GRBs) are known to be the most violent explosions in the universe, and a variety of correlations between observable GRB properties have been proposed in the literature, but none of these correlations are valid for both long and short GRBs. In this paper we report the discovery of a universal correlation that is suitable for both long and short GRBs using three prompt emission properties of GRBs, i.e., the isotropic peak luminosity L
iso, the peak energy of the time-integrated prompt emission spectrum E
peak, and the “high signal” timescale T
0.45,

. This universal correlation involves properties of GRB prompt emission and does not require knowledge of the afterglow phase, which can be used as a relatively unbiased redshift estimator. Here we use this correlation to estimate the pseudoredshifts for short GRBs and then use the Lynden–Bell method to obtain a nonparametric estimate of their luminosity function and formation rate. The luminosity function is

for dim SGRBs and

for bright SGRBs, with the break point

. The local formation rate of SGRBs is about 15 events Gpc−3 yr−1 . This universal correlation may have important implications for GRB physics, implying that the long and short GRBs should share similar radiation processes.
HST Survey of the Orion Nebula Cluster in the H2O 1.4 μm Absorption Band. I. A Census of Substellar and Planetary-mass Objects
Authors: Robberto Massimo , Gennaro Mario , Ubeira Gabellini Maria Giulia , Hillenbrand Lynne A. , Pacifici Camilla , Ubeda Leonardo , Andersen Morten , Barman Travis , Bellini Andrea , Rio Nicola Da , de Mink Selma E. , Lodato Giuseppe , Manara Carlo Felice , Platais Imants , Pueyo Laurent , Strampelli Giovanni Maria , Tan Jonathan C. , Testi L. 
Published: June 2020

Abstract
In order to obtain a complete census of the stellar and substellar population, down to a few

in the ∼1 Myr old Orion Nebula Cluster, we used the infrared channel of the Wide Field Camera 3 of the Hubble Space Telescope with the F139M and F130N filters. These bandpasses correspond to the 1.4 μm H2O absorption feature and an adjacent line-free continuum region. Out of 4504 detected sources, 3352 (about 75%) appear fainter than m
130 = 14 (Vega mag) in the F130N filter, a brightness corresponding to the hydrogen-burning limit mass (

) at ∼1 Myr. Of these, however, only 742 sources have a negative F130M–F139N color index, indicative of the presence of H2O vapor in absorption, and can therefore be classified as bona fide M and L dwarfs, with effective temperatures T ≲ 2850 K at an assumed 1 Myr cluster age. On our color–magnitude diagram (CMD), this population of sources with H2O absorption appears clearly distinct from the larger background population of highly reddened stars and galaxies with positive F130M–F139N color index and can be traced down to the sensitivity limit of our survey, m
130 ≃ 21.5, corresponding to a 1 Myr old ≃3

planetary-mass object under about 2 mag of visual extinction. Theoretical models of the BT-Settl family predicting substellar isochrones of 1, 2, and 3 Myr down to ∼1

fail to reproduce the observed H2O color index at M ≲ 20

. We perform a Bayesian analysis to determine extinction, mass, and effective temperature of each substellar member of our sample, together with its membership probability.
Effects of General Relativistic Spin Precessions on the Habitability of Rogue Planets Orbiting Supermassive Black Holes
Authors: Iorio Lorenzo 
Published: June 2020

Abstract
Recently, the possibility that several starless telluric planets may form around supermassive black holes (SMBHs) and receive energy input from the hole’s accretion disk, which, under certain plausible circumstances, may make them habitable in a terrestrial sense, has gained increasing attention. In particular, an observer on a planet orbiting at distance r = 100 Schwarzschild radii from a maximally rotating Kerr SMBH with mass M
• = 1 × 108
M
⊙ in a plane slightly outside the equator of the latter, would see the gravitationally lensed accretion disk the same size as the Sun as seen from Earth. Moreover, the accretion rate might be imagined to be set in such a way that the apparent disk’s temperature would be identical to that of the solar surface. We demonstrate that the post-Newtonian (pN) de Sitter and Lense–Thirring precessions of the spin axis of such a world would rapidly change, among other things, its tilt, ε, to its orbital plane by tens to hundreds of degrees over a time span of, say, just Δt = 400 yr, strongly depending on the obliquity η
• of the SMBH’s spin to the orbital plane. Thus, such relativistic features would have per se a relevant impact on the long-term habitability of the considered planet. Other scenarios are examined as well.
Pulsar Glitch Detection with a Hidden Markov Model
Authors: Melatos A. , Dunn L. M. , Suvorova S. , Moran W. , Evans R. J. 
Published: June 2020

Abstract
Pulsar timing experiments typically generate a phase-connected timing solution from a sequence of times of arrival (TOAs) by absolute pulse numbering, i.e., by fitting an integer number of pulses between TOAs in order to minimize the residuals with respect to a parameterized phase model. In this observing mode, rotational glitches are discovered, when the residuals of the no-glitch phase model diverge after some epoch, and glitch parameters are refined by Bayesian follow-up. Here, we present an alternative, complementary approach which tracks the pulse frequency f and its time derivative

with a hidden Markov model (HMM), whose dynamics include stochastic spin wandering (timing noise) and impulsive jumps in f and

(glitches). The HMM tracks spin wandering explicitly, as a specific realization of a discrete-time Markov chain. It discovers glitches by comparing the Bayes factor for glitch and no-glitch models. It ingests standard TOAs for convenience, and being fully automated, allows performance bounds to be calculated quickly via Monte Carlo simulations. Practical, user-oriented plots of the false-alarm probability and detection threshold (e.g., minimum resolvable glitch size) versus observational scheduling parameters (e.g., TOA uncertainty, mean delay between TOAs) and glitch parameters (e.g., transient and permanent jump sizes, exponential recovery timescale) are presented. The HMM is also applied to ∼1 yr of real data bracketing the 2016 December 12 glitch in PSR J0835−4510 as a proof of principle. It detects the known glitch and confirms that no other glitch exists in the same data with size ≳10−7
f.
The PHLEK Survey: A New Determination of the Primordial Helium Abundance
Authors: Hsyu Tiffany , Cooke Ryan J. , Prochaska J. Xavier , Bolte Michael 
Published: June 2020

Abstract
We present Keck NIRSPEC and Keck NIRES spectroscopy of sixteen metal-poor galaxies that have pre-existing optical observations. The near-infrared (NIR) spectroscopy specifically targets the He i λ10830 Å emission line, due to its sensitivity to the physical conditions of the gas in H ii regions. We use these NIR observations, combined with optical spectroscopy, to determine the helium abundance of sixteen galaxies across a metallicity range

= 7.13–8.00. This data set is combined with two other samples where metallicity and helium abundance measurements can be secured: star-forming galaxies selected from the Sloan Digital Sky Survey spectroscopic database, and existing low-metallicity systems in the literature. We calculate a linear fit to these measurements, accounting for intrinsic scatter, and report a new determination of the primordial helium number abundance,

, which corresponds to a primordial helium mass fraction

. Using our determination of the primordial helium abundance in combination with the latest primordial deuterium measurement,

, we place a bound on the baryon density

and the effective number of neutrino species

. These values are in 1.3σ agreement with those deduced from the Planck satellite observations of the temperature fluctuations imprinted on the cosmic microwave background.
On the Origin of the Gamma-Ray Emission toward SNR CTB 37A with Fermi-LAT
Authors: Abdollahi Soheila , Ballet Jean , Fukazawa Yasushi , Katagiri Hideaki , Condon Benjamin 
Published: June 2020

Abstract
The middle-aged supernova remnant (SNR) CTB 37A is known to interact with several dense molecular clouds through the detection of shocked H2 and OH 1720 MHz maser emission. In the present work, we use eight years of Fermi-LAT Pass 8 data, with an improved point-spread function and an increased acceptance, to perform detailed morphological and spectral studies of the γ-ray emission toward CTB 37A from 200 MeV to 200 GeV. The best fit of the source extension is obtained for a very compact Gaussian model with a significance of 5.75σ and a 68% containment radius of 0.°116 ± 0.°014stat ± 0.°017sys above 1 GeV, which is larger than the TeV emission size. The energy spectrum is modeled as a LogParabola, resulting in a spectral index α = 1.92 ± 0.19 at 1 GeV and a curvature β = 0.18 ± 0.05, which becomes softer than the TeV spectrum above 10 GeV. The SNR properties, including a dynamical age of 6000 yr, are derived assuming the Sedov phase. From the multiwavelength modeling of emission toward the remnant, we conclude that the nonthermal radio and GeV emission is mostly due to the reacceleration of preexisting cosmic rays (CRs) by radiative shocks in the adjacent clouds. Furthermore, the observational data allow us to constrain the total kinetic energy transferred to the trapped CRs in the clouds. Based on these facts, we infer a composite nature for CTB 37A to explain the broadband spectrum and to elucidate the nature of the observed γ-ray emission.
The SAMI Galaxy Survey: Stellar Population Gradients of Central Galaxies
Authors: Santucci Giulia , Brough Sarah , Scott Nicholas , Montes Mireia , Owers Matt S. , van Sande Jesse , Bland-Hawthorn Joss , Bryant Julia J. , Croom Scott M. , Ferreras Ignacio , Lawrence Jon S. , López-Sánchez Ángel R. , Richards Samuel N. 
Published: June 2020

Abstract
We examine the stellar population radial gradients (age, metallicity, and [α/Fe]) of 96 passive central galaxies up to ∼2 R

e
in the SAMI Galaxy Survey. The targeted groups have a halo mass range of

. The main goal of this work is to determine whether central galaxies have different stellar population properties when compared to similarly massive satellite galaxies. For the whole sample, we find negative metallicity radial gradients, which show evidence of becoming shallower with increasing stellar mass. The age and [α/Fe] gradients are slightly positive and consistent with zero, respectively. The [α/Fe] gradients become more negative with increasing mass, while the age gradients do not show any significant trend with mass. We do not observe a significant difference between the stellar population gradients of central and satellite galaxies at fixed stellar mass. The mean metallicity gradients are

for central galaxies and

for satellites. The mean age and [α/Fe] gradients are consistent between central and satellite galaxies, within the uncertainties, with a mean value of

for centrals and

for satellites and

for centrals and

for satellites. The stellar population gradients of central and satellite galaxies show no difference as a function of halo mass. This evidence suggests that the inner regions of central passive galaxies form in a similar fashion to those of satellite passive galaxies, in agreement with a two-phase formation scenario.