bluuebunny/crossref_metadata_2025_split huggingface dataset:
Axial force coefficient of APFSDS projectile
Authors: Trakic Ammar 
Published: March 2021

Armor-piercing ammunition is primarily used to combat against heavy armored targets (tanks), but targets can be light armored vehicles, aircraft, warehouse, structures, etc. It has been shown that the most effective type of anti-tank ammunition in the world is the APFSDS ammunition (Armor Piercing Fin Stabilized Discarding Sabot). The APFSDS projectile flies to the target and with his kinetic energy acts on the target, that is, penetrates through armor and disables the tank and his crew. Since the projectile destroys target with his kinetic energy, then it is necessary for the projectile to have the high impact velocity.
The decrease in the velocity of a projectile, during flight, is mainly influenced by aerodynamic forces. The most dominant is the axial force due to the laid trajectory of the projectile. By knowing the axial force (axial force coefficient), it is possible to predict the impact velocity of the projectile, by external ballistic calculation, in function of the distance of the target, and to define the maximum effective range from the aspect of terminal ballistics.
In this paper two models will be presented for predicting axial force (the axial force coefficient) of an APFSDS projectile after discarding sabot. The first model is defined in STANAG 4655 Ed.1. This model is used to predict the axial force coefficient for all types of conventional projectiles. The second model for predicting the axial force coefficient of an APFSDS projectile, which is presented in the paper, is the CFD-model (Computed Fluid Dynamics).
INSTRUMENTO VÁLIDO PARA AVALIAÇÃO DA QUALIDADE DO CUIDADO NAS INSTITUIÇÕES DE LONGA PERMANÊNCIA PARA IDOSOS: UMA REVISÃO INTEGRATIVA
Authors: De Almeida Alexandre Márcio , Santos de Souza Nair 
Published: March 2021

Como a demanda por instituições de longa permanência para idosos (ILPIs) está expandindo, e venha ser relevante para os sistemas e saúde pública discutir o processo de avaliação das condições de saúde dos seus residentes. Em relação a estes acontecimentos, que tem despertado a preocupação a preocupação da sociedade, a interação do idoso em Instituição de Longa Permanência para Idosos (ILPIs) mostra-se como alternativa a ser considerada. Perante a este cenário, as premissas supracitadas, o presente estudo objetivou identificar, por meio de revisão integrativa, instrumentos de medida construídos especificamente para o gerenciamento e o cuidado de residentes idosos, em instituições de longa permanência. Em face do objetivo proposto, as demandas assistenciais e gerenciais das ILPI, programa para melhorar a qualidade do cuidado baseada na dimensão Atenção Centrada na Pessoa, utilizando instrumentos como Indicadores Observáveis da Qualidade do Cuidado nas Instituições de Longa Permanência para Idosos (IOQ) adaptado ao contexto nacional na versão brasileira do IOQ. Torna-se urgente a reformulação de políticas públicas que garantam um sistema de avaliação padronizado dos residentes de ILPIs no Brasil, sendo um desafio fazer com que os instrumentos desenvolvidos consigam se difundir e se efetivar no cotidiano dos profissionais dessas instituições.
AX UMa, an ab-type RR Lyrae Star with a Rapidly Decreasing Pulsation Period, and Its Binarity
Authors: Li L.-J. , Qian S.-B. , Zhu L.-Y. , He J.-J. , Fang X.-H. 
Published: March 2021

Abstract
The pulsation periods of RR Lyrae stars usually vary with time, and they are often used as probes to study the mechanism behind the variation. After the early discovery that the pulsation period of the RR Lyrae star AX UMa decreased rapidly, in further research, we made multiband photometric observations of this star using the Sino-Thai 70 cm telescope and the 60 cm telescope at Yunnan Observatories, and collected its light-curve data from several photometry sky surveys. The O–C diagram confirmed that AX UMa has a rapid period decrease with a rate of −7.752 ± 0.005 days Myr−1, which indicates that it is the fastest-period decreasing ab-type RR Lyrae star in the Galactic field. Moreover, the O – C residuals contain additional periodic variations. We suppose that the variation with a long period is probably caused by the light-travel time effect as the star orbits in a binary system. The calculation shows that the lower mass limit of the companion is about 1 M
⊙. Combined with the full amplitudes and color indexes, we suggested that the companion is probably a hot subdwarf star. We compared the light curves of AX UMa and those of another binary evolution pulsator, OGLE-BLG-RRLYR-02792, and found that the former shows the characteristics of ab-type RR Lyrae stars, while the latter is more like an extreme long-period c-type RR Lyrae star. However, the absence of a bump in the light curves implies that the mass loss has occurred in the outer atmosphere of AX UMa. The special features of AX UMa make it worth more attention and further observations.
Cosmology with Galaxy Cluster Weak Lensing: Statistical Limits and Experimental Design
Authors: Wu Hao-Yi , Weinberg David H. , Salcedo Andrés N. , Wibking Benjamin D. 
Published: March 2021

Abstract
We forecast constraints on the amplitude of matter clustering σ
8(z) achievable with the combination of cluster weak lensing and number counts, in current and next-generation weak lensing surveys. We advocate for an approach, analogous to galaxy–galaxy lensing, in which the observables in each redshift bin are the mean number counts and the mean weak lensing profile of clusters above a mass proxy threshold. The primary astrophysical nuisance parameter is the logarithmic scatter

between the mass proxy and true mass near the threshold. For surveys similar to the Dark Energy Survey (DES), the Roman Space Telescope High Latitude Survey (HLS), and the Rubin Observatory Legacy Survey of Space and Time (LSST), we forecast aggregate precision on σ
8 of 0.26%, 0.24%, and 0.10%, respectively, if the mass–observable scatter is known externally to

. These constraints would be degraded by about 20% for

in the case of DES or HLS and for

for LSST. A 1 month observing program with Roman Space Telescope targeting ∼2500 massive clusters could achieve a ∼ 0.5% constraint on σ
8(z = 0.7) on its own, or a ∼ 0.33% constraint in combination with the HLS. Realizing the constraining power of clusters Requires accurate knowledge of the mass–observable relation and stringent control of systematics. We provide analytic approximations to our numerical results that allow for easy scaling to other survey assumptions or other methods of cluster mass estimation.
The RS CVn–type Star GT Mus Shows Most Energetic X-Ray Flares Throughout the 2010s
Authors: Sasaki Ryo , Tsuboi Yohko , Iwakiri Wataru , Nakahira Satoshi , Maeda Yoshitomo , Gendreau Keith , Corcoran Michael F. , Hamaguchi Kenji , Arzoumanian Zaven , Markwardt Craig B. , Enoto Teruaki , Sato Tatsuki , Kawai Hiroki , Mihara Tatehiro , Shidatsu Megumi , Negoro Hitoshi , Serino Motoko 
Published: March 2021

Abstract
We report that the RS CVn–type star GT Mus (HR 4492, HD 101379+HD 101380) was the most active star in the X-ray sky in the last decade in terms of the scale of recurrent energetic flares. We detected 11 flares from GT Mus in 8 yr of observations with the Monitor of All-sky X-ray Image (MAXI) from 2009 August to 2017 August. The detected flare peak luminosities were 1–4 × 1033 erg s−1 in the 2.0–20.0 keV band for its distance of 109.6 pc. Our timing analysis showed long durations (τ
r + τ
d) of 2–6 days with long decay times (τ
d) of 1–4 days. The released energies during the decay phases of the flares in the 0.1–100 keV band were in the range of 1–11 × 1038 erg, which are at the upper end of the observed stellar flare. The released energies during the whole duration were in the range of 2–13 × 1038 erg in the same band. We carried out X-ray follow-up observations for one of the 11 flares with the Neutron star Interior Composition Explorer (NICER) on 2017 July 18 and found that the flare cooled quasi-statically. On the basis of a quasi-static cooling model, the flare loop length is derived to be 4 × 1012 cm (or 60 R
☉). The electron density is derived to be 1 × 1010 cm−3, which is consistent with the typical value of solar and stellar flares (1010–13 cm−3). The ratio of the cooling timescales between radiative (τ
rad) and conductive (τ
cond) cooling is estimated to be τ
rad ∼ 0.1 τ
cond from the temperature; thus, radiative cooling was dominant in this flare.
On the Progenitors of AM CVn Stars as LISA Sources: The Evolved Donor Star Channel
Authors: Liu Wei-Min , Jiang Long , Chen Wen-Cong 
Published: March 2021

Abstract
The space gravitational wave (GW) detector Laser Interferometer Space Antenna (LISA) that is planned to be launched in the early 2030s will detect the low-frequency GW signals in the Galaxy. AM CVn stars were generally thought to be important low-frequency GW sources. Employing the MESA code, in this work we calculate the evolution of a great number of binary systems consisting of a white dwarf (WD) and a main sequence (MS) star, and diagnose whether their descendant-AM CVn stars will be visible with LISA. The simulated results show that the progenitors of these LISA sources, within a distance of 1 kpc, are WD–MS binaries with a donor star of 1.0–1.4 M
⊙ (for initial WD mass of 0.5 M
⊙) or 1.0–2.0 M
⊙ (for initial WD mass of 0.7 M
⊙), and an initial orbital period slightly smaller than the bifurcation period. Our simulations also indicate that 10 verification AM CVn sources can be reproduced by the standard magnetic braking model, and are potential LISA sources. Based on the birth rate of AM CVn stars simulated by the population synthesis, the birth rate of AM CVn-LISA sources evolving from the evolved donor star channel within a distance of 1 kpc can be estimated to be (0.6–1.4) × 10−6 yr−1, and the predicted number of AM CVn-LISA sources is about 340–810. Therefore, the evolved donor star channel plays an important role in forming AM CVn-LISA sources in the Galaxy.
The Perseus ALMA Chemistry Survey (PEACHES). I. The Complex Organic Molecules in Perseus Embedded Protostars
Authors: Yang Yao-Lun , Sakai Nami , Zhang Yichen , Murillo Nadia M. , Zhang Ziwei E. , Higuchi Aya E. , Zeng Shaoshan , López-Sepulcre Ana , Yamamoto Satoshi , Lefloch Bertrand , Bouvier Mathilde , Ceccarelli Cecilia , Hirota Tomoya , Imai Muneaki , Oya Yoko , Sakai Takeshi , Watanabe Yoshimasa 
Published: March 2021

Abstract
To date, about two dozen low-mass embedded protostars exhibit rich spectra with lines of complex organic molecules (COMs). These protostars seem to possess a different enrichment in COMs. However, the statistics of COM abundance in low-mass protostars are limited by the scarcity of observations. This study introduces the Perseus ALMA Chemistry Survey (PEACHES), which aims at unbiasedly characterizing the chemistry of COMs toward the embedded (Class 0/I) protostars in the Perseus molecular cloud. Of the 50 embedded protostars surveyed, 58% of them have emission from COMs. 56%, 32%, and 40% of the protostars have CH3OH, CH3OCHO, and N-bearing COMs, respectively. The detectability of COMs depends neither on the averaged continuum brightness temperature, a proxy of the H2 column density, nor on the bolometric luminosity and the bolometric temperature. For the protostars with detected COMs, CH3OH has a tight correlation with CH3CN, spanning more than two orders of magnitude in column densities normalized by the continuum brightness temperature, suggesting a chemical relation between CH3OH and CH3CN and a large chemical diversity in the PEACHES samples at the same time. A similar trend with more scatter is also found between all identified COMs, which hints at a common chemistry for the sources with COMs. The correlation between COMs is insensitive to the protostellar properties, such as the bolometric luminosity and the bolometric temperature. The abundance of larger COMs (CH3OCHO and CH3OCH3) relative to that of smaller COMs (CH3OH and CH3CN) increases with the inferred gas column density, hinting at an efficient production of complex species in denser envelopes.
Discovery of an Ultra-faint Stellar System near the Magellanic Clouds with the DECam Local Volume Exploration Survey
Authors: Cerny W. , Pace A. B. , Drlica-Wagner A. , Ferguson P. S. , Mau S. , Adamów M. , Carlin J. L. , Choi Y. , Erkal D. , Johnson L. C. , Li T. S. , Martínez-Vázquez C. E. , Mutlu-Pakdil B. , Nidever D. L. , Olsen K. A. G. , Pieres A. , Tollerud E. J. , Simon J. D. , Vivas A. K. , James D. J. , Kuropatkin N. , Majewski S. , Martínez-Delgado D. , Massana P. , Miller A. E. , Neilsen E. H. , Noël N. E. D. , Riley A. H. , Sand D. J. , Santana-Silva L. , Stringfellow G. S. , Tucker D. L. ,   (DELVE Collaboration)
Published: March 2021

Abstract
We report the discovery of a new ultra-faint stellar system found near the Magellanic Clouds in the DECam Local Volume Exploration Survey. This new system, DELVE J0155−6815 (DELVE 2), is located at a heliocentric distance of D
⊙ = 71 ± 4 kpc, which places it at a 3D physical separation of 12 ± 3 kpc from the center of the Small Magellanic Cloud and

from the center of the Large Magellanic Cloud (LMC). DELVE 2 is identified as a resolved overdensity of old (τ > 13.3 Gyr) and metal-poor (

dex) stars with a projected half-light radius of

and an absolute magnitude of

. The size and luminosity of DELVE 2 are consistent with both the population of recently discovered ultra-faint globular clusters and the smallest ultra-faint dwarf galaxies. However, its photometrically derived age and metallicity would place it among the oldest and most metal-poor globular clusters in the Magellanic system. In the absence of spectroscopic measurements of the system’s metallicity dispersion and internal kinematics, we are unable to conclusively classify this system at this time. DELVE 2 is detected in Gaia DR2 with a clear proper-motion signal, with multiple blue horizontal-branch stars near the centroid of the system with proper motions consistent with the systemic mean. We measure the system proper motion to be

=

mas yr−1. We compare the spatial position and proper motion of DELVE 2 with simulations of the accreted satellite population of the LMC and find that it is very likely to be associated with the LMC.
VLBI Observations of Supernova PTF11qcj: Direct Constraints on the Size of the Radio Ejecta
Authors: Palliyaguru N. T. , Corsi A. , Pérez-Torres M. , Varenius E. , Van Eerten H. 
Published: March 2021

Abstract
We present High Sensitivity Array and enhanced Multi-Element Remotely Linked Interferometer Network observations of the radio-loud broad-lined Type Ic supernova PTF11qcj obtained ∼7.5 yr after the explosion. Previous observations of this supernova at 5.5 yr since explosion showed a double-peaked radio light curve accompanied by a detection in the X-rays, but no evidence for broad Hα spectral features. The Very Long Baseline Interferometry (VLBI) observations presented here show that the PTF11qcj GHz radio ejecta remains marginally resolved at the submilliarcsecond level ≈7.5 yr after the explosion, pointing toward a nonrelativistic expansion. Our VLBI observations thus favor a scenario in which the second peak of the PTF11qcj radio light curve is related to the strong interaction of the supernova ejecta with a circumstellar medium of variable density, rather than to the emergence of an off-axis jet. Continued VLBI monitoring of PTF11qcj in the radio may further strengthen this conclusion.
Testing the High-latitude Curvature Effect of Gamma-Ray Bursts with Fermi Data: Evidence of Bulk Acceleration in Prompt Emission
Authors: Li Liang , Zhang Bing 
Published: March 2021

Abstract
When a gamma-ray burst (GRB) emitter stops emission abruptly, the observer receives rapidly fading emission from high latitudes with respect to the line of sight, known as the “curvature effect.” Identifying such emission from GRB prompt-emission lightcurves would constrain the radius of prompt emission from the central engine and the composition of GRB jets. We perform a dedicated search of high-latitude emission (HLE) through spectral and temporal analyses of a sample of single-pulse bursts detected by the Gamma-ray Burst Monitor on board the Fermi satellite. We identify HLE from a subsample of bursts and constrain the emission radius to be R
GRB ∼ (1015–1016) cm from the central engine. Some bursts have the HLE decay faster than predicted by a constant Lorentz factor jet, suggesting that the emission region is undergoing acceleration during prompt emission. This supports the Poynting-flux-dominated jet composition for these bursts. The conclusion is consistent with previous results drawn from spectral-lag modeling of prompt emission and HLE analysis of X-ray flares.
3D Solar Coronal Loop Reconstructions with Machine Learning
Authors: Chifu Iulia , Gafeira Ricardo 
Published: March 2021

Abstract
The magnetic field plays an essential role in the initiation and evolution of different solar phenomena in the corona. The structure and evolution of the 3D coronal magnetic field are still not very well known. A way to ascertain the 3D structure of the coronal magnetic field is by performing magnetic field extrapolations from the photosphere to the corona. In previous work, it was shown that by prescribing the 3D-reconstructed loops’ geometry, the magnetic field extrapolation produces a solution with a better agreement between the modeled field and the reconstructed loops. This also improves the quality of the field extrapolation. Stereoscopy, which uses at least two view directions, is the traditional method for performing 3D coronal loop reconstruction. When only one vantage point of the coronal loops is available, other 3D reconstruction methods must be applied. Within this work, we present a method for the 3D loop reconstruction based on machine learning. Our purpose for developing this method is to use as many observed coronal loops in space and time for the modeling of the coronal magnetic field. Our results show that we can build machine-learning models that can retrieve 3D loops based only on their projection information. Ultimately, the neural network model will be able to use only 2D information of the coronal loops, identified, traced, and extracted from the extreme-ultraviolet images, for the calculation of their 3D geometry.
Lost in the matrix : rationalisations en tension pour les ingénieurs aéronautiques
Authors: Coutant Hadrien 
Published: March 2021

Les organisations industrielles contemporaines, en particulier les organisations « matricielles », supposées répondre aux limites des organisations bureaucratiques, sont caractérisées par une multiplication des dispositifs de rationalisation. Poursuivant des objectifs différents, quoique tous orientés vers une recherche de plus grande efficacité productive, ces dispositifs se déclinent en diverses rationalisations formelles qui entrent bien souvent en tension les unes avec les autres. L’étude de l’organisation d’une division de recherche et développement en électronique et logiciel aéronautiques montre que ces tensions entre rationalisations ont des effets paradoxaux. Plutôt que de rendre l’organisation plus prévisible, ces dispositifs entraînent à la fois une repolitisation de l’organisation et le renforcement d’une collégialité technique. Au-delà de l’étude des dysfonctionnements bureaucratiques, l’article propose une réflexion sur les jeux locaux induits par les espaces de tensions entre rationalisations.
A cross-sectional study on current prescription trends and errors in outpatient department of a Bangladeshi secondary care district hospital
Authors: Rahman Md. Mizanur , Munia Ashfia Tasnim , Sikdar K. M. Yasif Kayes , Sarkar Md Raihan 
Published: March 2021

Context:
The rational prescription leads to a healthy and good-quality life of a patient. Irrational, inappropriate, and unnecessary prescriptions are major therapeutic issues in Bangladesh, which can cause severe consequences.

Aim:
This cross-sectional study was conducted to evaluate the prescription patterns and errors as well as to review the most frequently prescribed drug classes among outpatients at a secondary hospital in Pabna, a district of Bangladesh.

Methods:
A total of 400 prescriptions were reviewed from March 2019 to May 2019. In this study, statistical data analysis was implemented by IBM SPSS Statistics V22 and data revealed in frequencies, mean, and percentage. Spearman's rank correlation coefficient was calculated to show the correlation between bivariate coded variables.

Results:
The results revealed that majority of the prescription were prescribed for females (73.5%) where proton-pump inhibitors (PPIs), analgesics, vitamins, and single antibiotics were most frequently prescribed medicine for the female patients compared to male patients. Almost half of the collected prescription contained four medicines (47%). Maximum number of prescriptions contained two (30.5%) essential drugs and among 1402 medicines of 400 prescriptions, antiulcerants were most frequently prescribed medicine (23.32%) where esomeprazole was highly prescribed generic drug (44.75%). Moreover, Spearman's rank correlation coefficient suggested that PPIs and analgesics were frequently prescribed medicines at a time for the patients (0.182). According to the age group, the study also got some significant variations in prescribing pattern. However, most common prescription errors were prescriber's name not mentioned (100%), diagnosis not mentioned (96.75%), dose not indicated (15.41%), and wrong drug name (0.36%).

Conclusion:
Findings of the current study represent the existing prescribing trends of different therapeutic classes of drugs and common prescription errors in a secondary health facility of Bangladesh. From this study, it is observed that physicians prescribed rationally in some cases but need to ensure rationality in all prescriptions. Continuous monitoring of drug use, development of prescribing guidelines, and training are recommended to ensure and implement good-quality prescribing practices for promoting the rational and cost-effective use of drugs.
Neuroprotective Effects of San-Jia-Fu-Mai Decoction
Authors: Qu Chang , Liu Ling , Xu Qing-Qing , Xian Yan-Fang , Lin Zhi-Xiu 
Published: March 2021

Objective:
The objective of this study was to investigate whether 70% aqueous ethanol extract of San-Jia-Fu-Mai decoction extract (SJFMDE) could protect against 1-methyl-4-phenylpyridinium (MPP+)-induced oxidative stress in PC12 cells and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced motor function deficits in mice.

Materials and Methods:
The cell viability, the levels of intracellular reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) in the MPP+-treated PC12 cells were measured. Motor function deficits and dopamine (DA) level in the brain striatum and tyrosine hydroxylase (TH)-positive cells in substantia nigra pars compacta (SNc) of the MPTP-treated mice were determined.

Results:
The results showed that SJFMDE could reduce cell death and the levels of ROS and MDA while increase the level of GSH in the MPP+-treated PC12 cells. In addition, in vivo studies showed that oral administration of SJFMDE (3, 6, and 12 g/kg) significantly improved the motor function deficits induced by MPTP and enhanced the DA level in the striatum and TH-positive neuronal cells in SNc of the MPTP-treated mice.

Conclusions:
Our results revealed that SJFMDE possessed neuroprotective effects against neurotoxicity induced by MPP + and motor function deficits induced by MPTP via suppressing oxidative stress and increasing the levels of DA and TH, indicating that SJFMDE might be a promising Chinese medicine formula for the treatment of Parkinson's disease.