bluuebunny/crossref_metadata_2025_split huggingface dataset:
Re-estimating the Spin Parameter of the Black Hole in Cygnus X-1
Authors: Zhao Xueshan , Gou Lijun , Dong Yanting , Zheng Xueying , Steiner James F. , Miller-Jones James C. A. , Bahramian Arash , Orosz Jerome A. , Feng Ye 
Published: February 2021

Abstract
Cygnus X-1 is a well-studied persistent black hole X-ray binary. Recently, the three parameters needed to estimate the black hole spin of this system, namely the black hole mass M, the orbital inclination i, and the source distance D, have been updated. In this work we redetermine the spin parameter using the continuum-fitting technique for those updated parameter values. Based on the assumption that the spin axis of the black hole is aligned with the orbital plane, we fit the thermal disk component to a fully relativistic thin accretion disk model. The error in the spin estimate arising from the combined observational uncertainties is obtained via Monte Carlo simulations. We demonstrate that, without considering the counteracting torque effect, the new spin parameter is constrained to be a
* > 0.9985 (3σ), which confirms that the spin of the black hole in Cygnus X-1 is extreme.
Detection of Energy Cutoffs in Flare-accelerated Electrons
Authors: Xia Fanxiaoyu , Su Yang , Wang Wen , Wang Linghua , Warmuth Alexander , Gan Weiqun , Li Youping 
Published: February 2021

Abstract
Energy cutoffs in electron distribution define the lower and upper limits on the energy range of energetic electrons accelerated in solar flares. They are crucial parameters for understanding particle acceleration processes and energy budgets. Their signatures have been reported in studies of flattened flare X-ray spectra, i.e., the impulsive emission of nonthermal bremsstrahlung from energetic electrons impacting ambient, thermal plasma. However, these observations have not provided unambiguous constraints on the cutoffs. Moreover, other processes may result in similar spectral features. Even the existence and necessity of cutoffs as physical parameters of energetic electrons have been under debate. Here we report a search for their signatures in flare-accelerated electrons with two approaches, i.e., in both X-ray spectra and solar energetic particle (SEP) events. These represent two different electron populations, but may contain information of the same acceleration process. By studying a special group of late impulsive flares, and a group of selected SEP events, we found evidence of cutoffs revealed in both X-ray spectra and SEP electron distributions. In particular, we found for the first time consistent low- and high-energy cutoffs in both hard X-ray-producing and escaping electrons in two events. We also showed the importance of high-energy cutoff in studies of spectral shapes. These results provide evidence of cutoffs in flare-accelerated energetic electrons and new clues for constraining electron distribution parameters and particle acceleration models.
The Fundamental Plane of Massive Quiescent Galaxies at z ∼ 2
Authors: Stockmann Mikkel , Jørgensen Inger , Toft Sune , Conselice Christopher J. , Faisst Andreas , Margalef-Bentabol Berta , Gallazzi Anna , Zibetti Stefano , Brammer Gabriel B. , Gómez-Guijarro Carlos , Hirschmann Michaela , Lagos Claudia D. , Valentino Francesco M. , Zabl Johannes 
Published: February 2021

Abstract
We examine the Fundamental Plane (FP) and mass-to-light ratio (M/L) scaling relations using the largest sample of massive quiescent galaxies at 1.5 < z < 2.5 to date. The FP (r

e
, σ

e
, I

e
) is established using 19 UVJ quiescent galaxies from COSMOS with Hubble Space Telescope H

F160W
rest-frame optical sizes and X-shooter absorption line-measured stellar velocity dispersions. For a very massive,

log
(

M

*

/

M

⊙

)
>
11.26

, subset of eight quiescent galaxies at z > 2, from Stockmann et al., we show that they cannot passively evolve to the local Coma cluster relation alone and must undergo significant structural evolution to mimic the sizes of local massive galaxies. The evolution of the FP and M/L scaling relations, from z = 2 to present day, for this subset are consistent with passive aging of the stellar population and minor merger structural evolution into the most massive galaxies in the Coma cluster and other massive elliptical galaxies from the MASSIVE Survey. Modeling the luminosity evolution from minor merger-added stellar populations favors a history of merging with “dry” quiescent galaxies.
Evolution of the Nonpotential Magnetic Field in the Solar Active Region 12673 Based on a Nonlinear Force-free Modeling
Authors: Yamasaki Daiki , Inoue Satoshi , Nagata Shin’ichi , Ichimoto Kiyoshi 
Published: February 2021

Abstract
Active region (AR) 12673 has produced many M-class and several X-class flares, one of which being an X9.3 flare, which is recorded as the largest solar flare in solar cycle 24. We studied the evolution of the three-dimensional flare-productive magnetic field within AR 12673, using a time series of nonlinear force-free field extrapolations of every 12 hr from 2017 September 4 00:00 UT to 6 00:00 UT. Our analysis found that three magnetic flux ropes (MFRs) formed by September 4, one of which produced the X9.3 flare on September 6. One MFR has positive magnetic twist, which is a different sign from the other two MFRs. Since the temporal evolution of the magnetic flux of the MFR accumulating the positive twist is consistent with the profile of the GOES X-ray flux well observed from September 4 to 6, we suggest that the formation of the MFR having the positive twist is closely related to the occurrence of the M-class flares, including an M5.5 flare. We further found a magnetic null in the magnetic field surrounding the MFRs, in particular above the MFR having positive twist before the M5.5 flare, which is the largest M-flare observed during this period. By comparing with Atmospheric Imaging Assembly 1600 Å images, we found that the footpoints of the overlying field lines are anchored to the area where the brightening was initially observed. Therefore, we suggest that reconnection induced by the torus instability of the positively twisted MFR at the null possibly drove the M5.5 flare.
Luminosity Functions and Host-to-host Scatter of Dwarf Satellite Systems in the Local Volume
Authors: Carlsten Scott G. , Greene Jenny E. , Peter Annika H. G. , Beaton Rachael L. , Greco Johnny P. 
Published: February 2021

Abstract
Low-mass satellites around Milky Way (MW)-like galaxies are important probes of small-scale structure and galaxy formation. However, confirmation of satellite candidates with distance measurements remains a key barrier to fast progress in the Local Volume (LV). We measure the surface brightness fluctuation distances to recently cataloged candidate dwarf satellites around 10 massive hosts within D < 12 Mpc to confirm association. The satellite systems of these hosts are complete and mostly cleaned of contaminants down to M

g
∼ −9 to −10, within the area of the search footprints. Joining this sample with hosts surveyed to comparable or better completeness in the literature, we explore how well cosmological simulations combined with common stellar to halo mass relations (SHMR) match observed satellite luminosity functions in the classical satellite luminosity regime. Adopting an SHMR that matches hydrodynamic simulations, we find that the predicted overall satellite abundance agrees well with the observations. The MW is remarkably typical in its luminosity function among LV hosts. We find that the host-to-host scatter predicted by the model is in close agreement with the scatter between the observed systems, once the different masses of the observed systems are taken into account. However, we find significant evidence that the observed systems have more bright and fewer faint satellites than the SHMR model predicts, possibly necessitating a higher normalization of the SHMR around halo masses of 1011
M
⊙ or significantly greater scatter than present in common SHMRs. These results demonstrate the utility of nearby satellite systems in inferring the galaxy–subhalo connection in the low-mass regime.
Spectral Line Asymmetries of Hot Fe Lines in Multiloop Models
Authors: Mandage Revati S. , Bradshaw Stephen J. 
Published: February 2021

Abstract
Extreme ultraviolet emission line profiles often show asymmetries, in the form of wing enhancements, during solar flares. Various explanations, ranging from magnetic disturbances to non-Maxwellian electron distributions to plasma turbulence have been proposed to explain these features. Plasma dynamics in a single loop can also satisfactorily explain line asymmetry. However, the presence of sub-resolution structures, confirmed by increasingly high-resolution observations, and observational difficulties in isolating a monolithic loop from nearby loops, necessitate detailed modeling efforts to investigate the effect of superposed dynamics on some line asymmetries. In the present work, we design multiloop models, representative of three possible loop configurations, to study how the resultant Fe xxiii spectral line profiles differ in each case and examine the differences between these multiloop models and the single loop model. We also briefly explore the role of a constant time delay in heating successive sub-loops on the spectral line shape. We find that for a multiloop model with sub-loops of the same length, heating time delay is an important factor that alters the line profile shape from the single loop case. Whereas, multiloop models with sub-loops of varied lengths predict significantly different line profiles, such as asymmetric lines for longer durations and with large blueshifts, without the necessity of introducing time delays.
Radio Monitoring of the Tidal Disruption Event Swift J164449.3+573451. IV. Continued Fading and Non-relativistic Expansion
Authors: Cendes Y. , Eftekhari T. , Berger E. , Polisensky E. 
Published: February 2021

Abstract
We present continued radio and X-ray observations of the previously relativistic tidal disruption event (TDE) Swift J164449.3+573451 (Sw 1644+57) extending to about 9.4 yr post disruption, as part of ongoing campaigns with the Jansky Very Large Array (VLA) and the Chandra X-ray observatory. We find that the X-ray emission has faded below detectable levels, with an upper limit of ≲3.5 × 10−15 erg cm−2 s−1 in a 100 ks observation, while the radio emission continues to be detected and steadily fade. Both are consistent with forward shock emission from a non-relativistic outflow, although we find that the radio spectral energy distribution is better fit at these late times with an electron power-law index of p ≈ 3 (as opposed to p ≈ 2.5 at earlier times). With the revised spectral index we find ϵ

B
≈ 0.01 using the radio and X-ray data, and a density of ≈0.04 cm3 at a radius of R ≈ 0.65 pc (R
sch ≈ 2 × 106
R
⊙) from the black hole. The energy scale of the blastwave is ≈1052 erg. We also report detections of Sw 1644+57 at 3 GHz from the first two epochs of the VLA Sky Survey (VLASS), and find that ∼102 off-axis Sw 1644+57-like events to z ∼ 0.5 may be present in the VLASS data. Finally, we find that Sw 1644+57 itself will remain detectable for decades at radio frequencies, although observations at sub-GHz frequencies will become increasingly important to characterize its dynamical evolution.
On the Maximum Mass of Neutron Stars and GW190814
Authors: Godzieba Daniel A. , Radice David , Bernuzzi Sebastiano 
Published: February 2021

Abstract
Motivated by the recent discovery of a compact object with mass in the range 2.5–2.67 M
⊙ in the binary merger GW190814, we revisit the question of the maximum mass of neutron stars (NSs). We use a Markov Chain Monte Carlo approach to generate about two million phenomenological equations of state with and without first-order phase transitions. We fix the crust equation of state and only assume causality at higher densities. We show how a strict upper bound on the maximum NS mass can be inferred from upcoming observation of NS radii and masses. The derived upper bounds depend only on relativity and causality, so it is not affected by nuclear physics uncertainties. We show how a lower limit on the maximum mass of NSs, in combination with upcoming measurements of NS radii by LIGO/Virgo and NICER, would constrain the equation of state of dense matter. Finally, we discuss the implications for GW190814.
Les compétences : maillon fort des structures d’accompagnement des PME
Authors: Aloui Adel , Wehbi Sleiman Manal 
Published: February 2021

Depuis quelques années, l’accompagnement suscite un intérêt grandissant, en témoignent le nombre et la diversité des contributions relatives à ce thème. Les PME, vu le contexte de crise actuel et du fait de leurs caractéristiques, ont besoin d’un accompagnement tout au long de leur cycle de vie et notamment dans leurs projets de développement et d’innovation. Dans ce travail, nous présentons les résultats d’une étude empirique dans le cadre de la création d’une structure d’accompagnement et nous mettrons en lumière l’importance de la prise en compte des compétences de ses acteurs. Cette étude présente un double intérêt ; tout d’abord, la qualité de l’accompagnement est étroitement liée, entre autres, aux compétences de l’accompagnant et à ses aptitudes à mener à bien ses missions. En plus, sur un plan organisationnel, le profil des accompagnants et leurs compétences sont déterminants dans la performance collective de la structure d’accompagnement et de son évolution.
Analisis Pengaruh Kepuasan Pelanggan Melalui Kualitas Produk Tape Ketan Daun Jambu
Authors: Afifah Afifah , Setiadi Roby , Mukson Mukson , Fitralisma Gian , Ikhwan Syariefull , Dwita Kumala Findhy 
Published: February 2021

Penelitian ini dilakukan untuk mengetahui serta mengukur kepuasan pelanggan melalui kualitas produk tape ketan daun jambu di Banjarharjo Kabupaten Brebes dengan menggunakan metode penelitian kuantitatif assosiatif. Peneliti membuat serta menyebar kuesioner kepada 30 responden yang merupakan sampel dari jumlah populasi pelanggan tape ketan daun jambu yang berada di Kecamatan Banjarharjo untuk dapat diteliti serta dianalisis sesuai dengan data yang telah disebar. Teknik analisis data pada penelitian ini menggunakan Uji Validitas, Uji Reliabilitas, Uji Regresi Sederhana, Uji Determinasi (R) dan Uji Hipotesis (Uji-t). Hasil distribusi responden penelitian ini adalah persepsi responden Kualitas Produk Tape Ketan Daun Jambu “Dio” memiliki nilai distribusi responden sebesar 4,11 dan masuk pada kategori interpretasi baik, dan persepsi responden terhadap kepuasan pelanggan tape ketan daun jambu “Dio” memiliki nilai distribusi responden dengan total 3,87 dan masuk pada kategori interpretasi puas. Sedangkan hasil pengujian yang diperoleh terdapat pengaruh positif kuat dan siginifikan antara kualitas produk Tape Ketan daun Jambu “Dio” terhadap kepuasan pelanggan. Hal ini dapat dilihat dari model Regresi Linier Sederhana Y = 4,477+ 1,616X, nilai koefisien korelasi r = 0,408, kontribusi variabel kualitas produk terhadap variabel kepuasan pelanggan sebesar 16,6%, pengaruh kualitas produk terhadap kepuasan pelanggan signifikan karena t hitung > t tabel (3,128 > 1,701).
Penerapan Metode Simple Additive Weighting (SAW) dalam Sistem Pengambilan Keputusan Order Persediaan Barang Berbasis Web
Authors: Marliana Iin 
Published: February 2021

Nowaday, computers already can be used to provide choices in taking of the decision, not only used for data processing or presenting information, process of taking the decision it self is the results of a system that called Sistem Pendukung Keputusan (SPK). The system of taking the decision is possible because there has been a development of hardware technology, integration of hardware and software. In the business sector one of them is a truck and expedition which engages in the transportation services of stuffs between Lampung-Surabaya cities and vice versa. In this expedition service consists of arround used by 76 units of cars. And the supply of stuffs still used bookkeeping which is sometimes taking of the decision supply of stuffs is still handled by superiors.
Therefore, this research used Simple Additive Weighting (SAW) method which is used to make decisions in problems solving by create a design system and building software. This research will create a system when taking the decision in the supply of stuffs in the Business Entity Expedition Services with SAW method by using WEB.
Leer y escribir como interpretación de roles, aprender de experiencias de estudiantes de doctorado
Authors: Carrasco Altamirano Alma Cecilia , Méndez Ochaita Margarita Flor de María , Brambila Limón Rocío , Encinas Prudencio María Teresa Fátima , Sánchez Hernández Verónica 
Published: February 2021

Este artículo reporta la investigación de las prácticas de escritura en dos programas de doctorado,en Fisiología y Oceanografía Física, para propiciar la construcción de vocaciones científicas desde el pregrado. Se optó por un paradigma cualitativo, utilizando entrevistas a profundidad con estudiantes, investigadores y administrativos, además de grupos focales con estudiantes. Para el análisis de los datos se utilizó el atlas.ti. Los resultados sugieren que los doctorandos se convierten en especialistas “en el trabajo” en un entorno colaborativo, supervisados y guiados por expertos. En este proceso formativo, los estudiantes juegan roles de autor, lector, crítico, editor y experto local al participar gradualmente en procesos de investigación, comités de política y gestión, paneles de revisión y comisiones de evaluación. Sobre todo, aprenden a escribir artículos, a revisarlos y a someterlos a dictaminaciones de comités científicos disciplinares.
Rotary Files in Pediatric Dentistry: From Then Till Now
Authors: Pitchiah Pragadeesh A , Shivashankarappa Prathima G 
Published: February 2021

ABSTRACT
The introduction of adult NiTi rotary file system for children was a revolution in the field of pediatric endodontics. With the use of these files, cost-effective, consistent obturations were made possible in shorter instrumentation time. The various restraints of adult rotary files such as file length and taper created the need for newer rotary file system. These voids were fulfilled with the advent of exclusive pediatric rotary file—Kedo-S file system. In this article, we have discussed how the innovative pediatric rotary files have made its mark overpowering the limitations of the existing adult rotary file system in children.
How to cite this article: Pitchiah PA, Shivashankarappa PG. Rotary Files in Pediatric Dentistry: From Then Till Now. J Sci Dent 2020;10(2):55–57.
Efficiency of Universal Back Resting Device in Public Health Dentistry Outreach Activities: A Cross-sectional Study among Patients and Service Care Providers
Authors: Benny Ashna M , Murugappan Senthil 
Published: February 2021

ABSTRACT

Aims and objectives
This study was undertaken to analyze the benefits and drawbacks of the universal back resting device (UBRD) and to use the obtained data to rectify defects if any and modify it for the betterment of treatment outcomes at camp sites.

Materials and methods
This is a cross-sectional questionnaire study undertaken among a group of 100 patients and 100 healthcare providers who have received treatment with the aid of and provided treatment with the UBRD, respectively. The data that were obtained by analyzed and percentages were calculated using SPSS 17 for windows.

Results
The results of this study conclusively pointed out that the UBRD meets the demands that it was intended for and it can also be used as an alternative to portable dental chairs at camp sites or even in primary health centers when the available funds are insufficient in ratio to the number of people requiring treatment. The possible alteration that can be made to the device to increase its efficiency was also noted.

Conclusion
The UBRD has proved to be useful in providing oral healthcare at camp sites and could be stated that it is a fair enough alternative to conventional chairs when minimum resources are available.

Clinical significance
The UBRD is a unique device that can aid in providing better treatment and is cost efficient and if it is implemented in camp/outreach sites, it would drastically increase the number of patients getting treated in a short period of time and to an efficiency level almost as equal as a portable dental chair.
How to cite this article
Benny AM, Murugappan S. Efficiency of Universal Back Resting Device in Public Health Dentistry Outreach Activities: A Cross-sectional Study among Patients and Service Care Providers. J Sci Dent 2020;10(2):34–37.
Knowledge of Stem Cells among Pregnant Women in Rural Areas of Puducherry
Authors: Arumugam Santha , Vinodine Joice , Guna Balavaishnavi , Gobinathan Parameshwari 
Published: February 2021

ABSTRACT
Stem cells are unique cells, as they have the potential to undergo repair and regeneration into a variety of distinct cell types of the body. These cells are of great importance in today's regenerative medicine and can be isolated from specific tissues of the body including oral cavity. Especially, stem cells obtained from the placenta and umbilical cord that were considered to be biologic waste can be used in the treatment of cancerous conditions also. Moreover, the recent past has plenty of studies carried out in pulpal stem cells from the dental tissues. Hence, the present study was conducted to assess the level of awareness and knowledge about different sources of stem cells and its importance among expectant mothers in rural areas of Puducherry population. Through this study, the knowledge of stem cells will be emphasized among the pregnant women.
How to cite this article: Arumugam SD, Vinodine J, Guna B, Gobinathan P. Knowledge of Stem Cells among Pregnant Women in Rural Areas of Puducherry. J Sci Dent 2020;10(2):32–33.
An Uncommon and Rare Soft Tissue Tumor of the Cheek (Schwannoma): A Case Report
Authors: Sathyanarayanan Ramanujam , Kumaravelu Raghu , Jude Nithin J 
Published: February 2021

ABSTRACT
Schwannoma is usually an uncommon, benign, encapsulated, very slow-growing, usually solitary tumor that originates from Schwann cells of the nerve sheath derived from the neuroectoderm. Only 1% of schwannomas was intraoral of which the most common site is always the tongue after which the palate, floor of the mouth, buccal mucosa, lips, and jaws can be affected. Schwannoma is an uncommon benign tumor that originates from the Schwan cell of the peripheral nerves. It is difficult to diagnose clinically. In our case, the patient reported a solitary swelling present on the left cheek. The swelling was warmth, tender, and consistency is soft. Inflamed buccal mucosa was also noted and the patient had restricted mouth opening. Then, surgical excision was done under general anesthesia.
How to cite this article: Kumaravelu R, Sathyanarayanan R, Jude NJ. An Uncommon and Rare Soft Tissue Tumor of the Cheek (Schwannoma): A Case Report. J Sci Dent 2020;10(2):38–40.