bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trabajo experimental no convencional para la enseñanza de la química de 4to año de educación media general
Authors: Portillo Urdaneta Stephanie Valeria 
Published: November 2022

El estudio tuvo como objetivo evaluar la efectividad que tiene la aplicación del trabajo experimental no convencional para la enseñanza de la Química de 4to año de Educación Media General, por medio de un enfoque empírico – inductivo con tipo y diseño metodológico evaluativo. Se aplicó 1 instrumento compuesto por 34 ítems con alternativa de respuesta siempre, casi siempre, casi nunca y nunca, con un alfa de cronbach de 0.97 altamente confiable, validado por el juicio de 5 expertos en el área. Se emplearon dos baremos para interpretar los resultados de promedio y desviación estándar, parámetros empleados para evaluar las respuestas de los 31 docentes de las 25 instituciones públicas y privadas que conforman el circuito 9 del municipio Maracaibo de estado Zulia y que constituyeron la población y posterior muestra de este estudio. Apoyados en las teorías de aprender por descubrimiento, aprender haciendo y la investigación dirigida. Los resultados sugieren que las prácticas de laboratorio son efectivas cuando son elaboradas con materiales y recursos del entorno del estudiante, ya que presentan contenidos conceptuales, procedimentales y actitudinales, puntuales en los que los estudiantes deben seguir algoritmos para llegar a una conclusión predeterminada. Además, el estudio revela que este tipo de estrategias promueve la enseñanza de la Química, por lo que se recomienda realizar la promulgación de este tipo de actividades.
Testing the Limits of AGN Feedback and the Onset of Thermal Instability in the Most Rapidly Star-forming Brightest Cluster Galaxies
Authors: Calzadilla Michael S. , McDonald Michael , Donahue Megan , McNamara Brian R. , Fogarty Kevin , Gaspari Massimo , Gitti Myriam , Russell Helen R. , Tremblay Grant R. , Voit G. Mark , Ubertosi Francesco 
Published: November 2022

Abstract
We present new, deep, narrow- and broadband Hubble Space Telescope observations of seven of the most star-forming brightest cluster galaxies (BCGs). Continuum-subtracted [OII] maps reveal the detailed, complex structure of warm (T ∼ 104 K) ionized gas filaments in these BCGs, allowing us to measure spatially resolved star formation rates (SFRs) of ∼60–600 M
⊙yr−1. We compare the SFRs in these systems and others from the literature to their intracluster medium cooling rates (

M

̇

cool

), measured from archival Chandra X-ray data, finding a best-fit relation of

log
(
SFR
)
=
(
1.66
±
0.17
)

log
(

M

̇

cool

)

+ (−3.22 ± 0.38) with an intrinsic scatter of 0.39 ± 0.09 dex. This steeper-than-unity slope implies an increasingly efficient conversion of hot (T ∼ 107 K) gas into young stars with increasing

M

̇

cool

, or conversely a gradual decrease in the effectiveness of AGN feedback in the strongest cool cores. We also seek to understand the physical extent of these multiphase filaments that we observe in cluster cores. We show, for the first time, that the average extent of the multiphase gas is always smaller than the radii at which the cooling time reaches 1 Gyr, the t
cool/t
ff profile flattens, and that X-ray cavities are observed. This implies a close connection between the multiphase filaments, the thermodynamics of the cooling core, and the dynamics of X-ray bubbles. Interestingly, we find a one-to-one correlation between the average extent of cool multiphase filaments and the radius at which the cooling time reaches 0.5 Gyr, which may be indicative of a universal condensation timescale in cluster cores.
The Stellar Mass Function in CANDELS and Frontier Fields: The Buildup of Low-mass Passive Galaxies since z ∼ 3
Authors: Santini Paola , Castellano Marco , Fontana Adriano , Fortuni Flaminia , Menci Nicola , Merlin Emiliano , Pagul Amanda , Testa Vincenzo , Calabrò Antonello , Paris Diego , Pentericci Laura 
Published: November 2022

Abstract
Despite significant efforts in recent years, the physical processes responsible for the formation of passive galaxies through cosmic time remain unclear. The shape and evolution of the stellar mass function (SMF) give an insight into these mechanisms. Taking advantage of the CANDELS and the deep Hubble Frontier Fields (HFF) programs, we estimated the SMF of total, star-forming, and passive galaxies from z = 0.25 to z = 2.75 to unprecedented depth and we focus on the latter population. The density of passive galaxies underwent a significant evolution over the last 11 Gyr. They account for 60% of the total mass in the nearby universe against ∼20% observed at z ∼ 2.5. The inclusion of the HFF program allows us to detect, for the first time at z > 1.5, the characteristic upturn in the SMF of passive galaxies at low masses, usually associated with environmental quenching. We observe two separate populations of passive galaxies evolving on different timescales: roughly half of the high-mass systems were already quenched at high redshift, while low-mass passive galaxies are gradually building up over the redshift range probed. In the framework of environmental quenching at low masses, we interpret this finding as evidence of an increasing role of the environment in the buildup of passive galaxies as a function of time. Finally, we compared our findings with a set of theoretical predictions. Despite good agreement in some redshift and mass intervals, none of the models are able to fully reproduce the observations. This calls for further investigation into the involved physical mechanisms, both theoretically and observationally, especially with the brand-new JWST data.
The Correlation between WISE 12 μm Emission and Molecular Gas Tracers on Subkiloparsec Scales in Nearby Star-forming Galaxies
Authors: Gao Yang , Tan Qing-Hua , Gao Yu , Fang Min , Chown Ryan , Jiao Qian , Luo Chun-Sheng 
Published: November 2022

Abstract
We complement the MALATANG sample of dense gas in nearby galaxies with archival observations of 12CO and its isotopologues to determine scaling relations between Wide-field Infrared Survey Explorer (WISE) 12 μm emission and molecular gas tracers at subkiloparsec scales. We find that 12 μm luminosity is more tightly correlated with 12CO than it is with 13CO or dense gas tracers. Residuals between predicted and observed 12CO are only weakly correlated with molecular gas mass surface density (Σmol) in regions where Σmol is very low (∼10 M
⊙ pc−2). Above this limit, the 12CO residuals show no correlations with physical conditions of molecular gas, while 13CO residuals depend on the gas optical depth and temperature. By analyzing differences from galaxy to galaxy, we confirm that the 12CO−12 μm relation is strong and statistically robust with respect to star-forming galaxies and active galactic nucleus hosts. These results suggest that WISE 12 μm emission can be used to trace total molecular gas instead of dense molecular gas, likely because polycyclic aromatic hydrocarbons (PAHs, a major contributor to WISE 12 μm emission) may be well mixed with the gas that is traced by 12CO. We propose that WISE 12 μm luminosity can be used to estimate molecular gas surface density for statistical analyses of the star formation process in galaxies.
Intermediate-mass Black Holes on the Run from Young Star Clusters
Authors: González Prieto Elena , Kremer Kyle , Fragione Giacomo , Martinez Miguel A. S. , Weatherford Newlin C. , Zevin Michael , Rasio Frederic A. 
Published: November 2022

Abstract
The existence of black holes (BHs) with masses in the range between stellar remnants and supermassive BHs has only recently become unambiguously established. GW190521, a gravitational wave signal detected by the LIGO/Virgo Collaboration, provides the first direct evidence for the existence of such intermediate-mass BHs (IMBHs). This event sparked and continues to fuel discussion on the possible formation channels for such massive BHs. As the detection revealed, IMBHs can form via binary mergers of BHs in the “upper mass gap” (≈40–120 M
⊙). Alternatively, IMBHs may form via the collapse of a very massive star formed through stellar collisions and mergers in dense star clusters. In this study, we explore the formation of IMBHs with masses between 120 and 500 M
⊙ in young, massive star clusters using state-of-the-art Cluster Monte Carlo models. We examine the evolution of IMBHs throughout their dynamical lifetimes, ending with their ejection from the parent cluster due to gravitational radiation recoil from BH mergers, or dynamical recoil kicks from few-body scattering encounters. We find that all of the IMBHs in our models are ejected from the host cluster within the first ∼500 Myr, indicating a low retention probability of IMBHs in this mass range for globular clusters today. We estimate the peak IMBH merger rate to be


≈
2

Gpc

−
3

yr

−
1

at redshift z ≈ 2.
Does the Gamma-Ray Binary LS I + 61°303 Harbor a Magnetar?
Authors: Suvorov Arthur G. , Glampedakis Kostas 
Published: November 2022

Abstract
The high-mass X-ray binary LS I + 61°303 is also cataloged as a gamma-ray binary as a result of frequent outbursts at TeV photon energies. The system has released two soft-gamma flares in the past, suggesting a magnetar interpretation for the compact primary. This inference has recently gained significant traction following the discovery of transient radio pulses, detected in some orbital phases from the system, as the measured rotation and tentative spin-down rates imply a polar magnetic field strength of B

p
≳ 1014 G if the star is decelerating via magnetic dipole braking. In this paper, we scrutinize magnetic field estimates for the primary in LS I + 61°303 by analyzing the compatibility of available data with the system’s accretion dynamics, spin evolution, age limits, gamma-ray emissions, and radio pulsar activation. We find that the neutron star’s age and spin evolution are theoretically difficult to reconcile unless a strong propeller torque is in operation. This torque could be responsible for the bulk of even the maximum allowed spin-down, potentially weakening the inferred magnetic field by more than an order of magnitude.
Dynamic Evolution of Magnetic Flux Ropes in Active Region 11429. I. EUV Observations
Authors: Zhang Yin , Liu Jihong , Tan Baolin , Zhu Xiaoshuai , Yan Yihua 
Published: November 2022

Abstract
Studying the formation and dynamic evolution of the magnetic flux rope (MFR) is key to understanding the physics of most solar eruptions. In the present study, we investigate the dynamic evolution of four MFRs, which involve in a major eruption. The MFR1, which represents as filament (F1), first appears about 31 hr before the major eruption. The MFR2 appears as a hot-channel with a small filament (F2) in its east part. The hot-channel becomes intermittently visible about 2 hr before the major eruption. The MFR3 is formed by the reconnection between MFR1 and MFR2. The annular components of MFR3 along the MFR2 part appear as a hollow helical structure from the background with the temperature of several MK after the reconnection. Coronal material then flows along the hollow structure from MFR1 part to MFR2 part to form a new filament (F3), which is hosted by MFR3 and acts as the axial component of MFR3 in the following evolution. The MFR4 appears during MFR3's eruption phase as conjugated extreme ultraviolet (EUV) brightenings. Both brightenings extend outward into irregular ribbons with conjugate EUV dimmings inside. Meanwhile, an erupted hot-channel, which roots in the conjugated brightening, is identified. The morphology of the MFRs are also profiled by four associated flare ribbon pairs. The on-disk observations shed light on our understanding of the topology of the MFRs and their formation and eruption. Further work should lay emphasis on the magnetic environment for the MFR formation and evolution.
The Disk Population in a Distant Massive Protocluster
Authors: Cheng Yu , Tan Jonathan C. , Tobin John J. , Fedriani Rubén , Andersen Morten , Wang Junfeng 
Published: November 2022

Abstract
The unprecedented angular resolution and sensitivity of the Atacama Large Millimeter/submillimeter Array make it possible to unveil disk populations in distant (>2 kpc), embedded young cluster environments. We have conducted an observation toward the central region of the massive protocluster G286.21+0.16 at 1.3 mm. With a spatial resolution of 23 mas and a sensitivity of 15 μJy beam−1, we detect a total of 38 protostellar disks. These disks have dust masses ranging from about 53 to 1825 M
⊕, assuming a dust temperature of 20 K. This sample is not closely associated with previously identified dense cores, as would be expected for disks around Class 0 protostars. Thus, we expect our sample, being flux-limited, to be mainly composed of Class I/flat-spectrum source disks, since these are typically more massive than Class II disks. Furthermore, we find that the distributions of disk masses and radii are statistically indistinguishable from those of the Class I/flat-spectrum objects in the Orion molecular cloud, indicating that similar processes are operating in G286.21+0.16 to regulate disk formation and evolution. The cluster center appears to host a massive protostellar system composed of three sources within 1200 au, including a potential binary with 600 au projected separation. Relative to this center, there is no evidence for widespread mass segregation in the disk population. We do find a tentative trend of increasing disk radius versus distance from the cluster center, which may point to the influence of dynamical interactions being stronger in the central regions.
Spatial Distribution and Low-frequency Disturbance Modulation of Magnetosheath Ion Polytropic Index
Authors: Pang Xuexia , Geng Xiyao , Wang Shiqun , Cao Jinbin , Deng Zechao , Duan Pingguang , Li Xuechen , Jia Pengying , Xu Longfei 
Published: November 2022

Abstract
We, using the Cluster data from 2001 to 2010, studied spatial distribution of the ion polytropic index in the magnetosheath, and the modulation of polytropic process by the low-frequency disturbances (4–18 mHz). The total of 30,3283 samples is divided into two sorts: quasi-perpendicular and quasi-parallel propagating ones. The median polytropic index increases with spreads narrowing from the bow shock to the magnetopause. The median polytropic indices are basically between isothermal and adiabatic in the inner magnetosheath, and between isothermal and isobaric in the outer magnetosheath. The spatial distributions of the correlation coefficient (CC) between the perturbed ion number density and the parallel magnetic field CC (δn, δB
∥) have a good correlation with those of polytropic index. The quasi-perpendicular disturbances are mostly mirror-like modes (D

r
≪ 1) except for some slow-mode disturbances (D

r
≥ 1) in the regions near the Sun–Earth line and the inner magnetosheath. The polytropic indices in the inner and middle magnetosheath modulated by mirror-like-mode disturbances are between 0.9 and 1.3. The quasi-parallel propagating low-frequency disturbances are predominantly slow modes in the inner and middle magnetosheath, and Alfvén modes in the outer magnetosheath. For the samples with quasi-parallel propagating disturbances, the polytropic processes are basically between isothermal and isobaric except near the magnetopause. The good correlation between the spatial distributions of polytropic index and low-frequency disturbances indicates that the distribution of the polytropic index in the magnetosheath is modulated by low-frequency disturbances.
Laboratory and Astronomical Discovery of Magnesium Dicarbide, MgC2
Authors: Changala P. B. , Gupta H. , Cernicharo J. , Pardo J. R. , Agúndez M. , Cabezas C. , Tercero B. , Guélin M. , McCarthy M. C. 
Published: November 2022

Abstract
We report the detection of magnesium dicarbide, MgC2, in the laboratory at centimeter wavelengths and assign 24MgC2, 25MgC2, and 26MgC2 to 14 unidentified lines in the radio spectrum of the circumstellar envelope of the evolved carbon star IRC+10216. The structure of MgC2 is found to be T-shaped with a highly ionic bond between the metal atom and the C2 unit, analogous to other dicarbides containing electropositive elements. A two-temperature excitation model of the MgC2 emission lines observed in IRC+10216 yields a very low rotational temperature of 6 ± 1 K, a kinetic temperature of 22 ± 13 K, and a column density of (1.0 ± 0.3) × 1012 cm−2. The abundance of MgC2 relative to the magnesium–carbon chains MgCCH, MgC4H, and MgC6H is 1:2:22:20 and provides a new constraint on the sequential radiative association–dissociative recombination mechanisms implicated in the production of metal-bearing molecules in circumstellar environments.
Self-medication with antibiotics and awareness of antibiotic resistance among population in Arar city, Saudi Arabia
Authors: Eltom Elhassan Hussein , Alanazi Abdallah Lafi , Alenezi Jamal Farhan , Alruwaili Ghazi Meshal , Alanazi Abdulaziz Mohammed , Hamayun Rahma 
Published: November 2022

Introduction: Self-medication with pharmaceutical products can be defined as the use of these products without a medical prescription, and the production, distribution, and sale of these products are the client’s responsibility, while they think it is within rational usage. Among these products, antibiotics remain the most serious problem leading to the spread of antibiotic resistance, with consequences of increased morbidity, mortality, and extended hospital stays.
Methodology: This is a cross-sectional study aimed to estimate the prevalence of self-medication with antibiotics among Arar city population and assessing their awareness of antibiotic resistance. Data had been collected through a self-administered validated online questionnaire. Data entry and analysis were performed using a statistical package for the social science program (SPSS) version 20.
Results: The overall number of respondents to our survey was 462, with 56.7% female and 43.3% male participants. The prevalence of self-medication with antibiotics was (77.5%). The main reasons for self-medication with antibiotics were ease of use (54.6%) and cost-saving (24.8%). When asked about what they think about self-medication with antibiotics for self-care, 20.1% of our participants thought that it is a good practice and 41.6% thought that it is an acceptable practice. 81.4 % of respondents thought that antibiotic resistance occurs when your body becomes resistant to antibiotics and no longer works well
Conclusions: In the Northern region, despite the open and rapid access to medical care services, it appears that a high proportion of young adult population prefers custom antibiotics without a medical prescription.
Salmonella gastroenteritis in children: six-year experience in İstanbul, Turkey
Authors: Karaaslan Ayşe , Çetin Ceren , Köle Mehmet Tolga , Demir Tekol Serap , Söbü Elif , Akın Yasemin 
Published: November 2022

Introduction: The aim of this study was to evaluate the demographic and clinical characteristics and treatment outcomes of children with Salmonella gastroenteritis.
Methodology: We retrospectively reviewed the medical records of pediatric patients aged between 1 month and 18 years with the diagnosis of Salmonella gastroenteritis between May 2015 and December 2021.
Results: A total of 172 children diagnosed with Salmonella gastroenteritis, including 113 outpatients and 59 hospitalized children, were included in this study. There were 95 (55.2%) males and 77 (44.8%) females with a median age of 59.5 months (interquartile range [IQR]: 33.5–96 months, min–max: 1–205 months). The most common clinical symptoms were diarrhea (n = 166, 96.5%), fever (n = 113, 65.7%) and abdominal pain (n = 73, 42.4%). Bloody diarrhea was seen in 19.2% of patients. Fifty (29.1%) of the Salmonella species could not be typed. Serogroup D (n = 106, 61.6%) was the predominant serogroup isolated from stool cultures, followed by serogroup B (n = 16, 9.3%). 62.2% of the isolates were susceptible to ampicillin, 97.7% to ciprofloxacin, 98.8% to trimethoprim-sulfamethoxazole, and 98.8% to ceftriaxone. Fever, vomiting, and underlying disease occurred more frequently in hospitalized patients than in outpatients (p: 0.005, p: 0.000, p: 0.000, respectively). C-reactive protein value was found to be higher in hospitalized patients (p: 0.000).
Conclusions: Salmonella should be considered as a causative agent in pediatric patients with abdominal pain, fever, and bloody-mucous diarrhea, and patients with severe clinical conditions should be hospitalized and antibiotic therapy initiated if indicated.
Species associated with whale sharks (Rhincodon typus) in the Galapagos Archipelago
Authors: Green Sofia , Hearn Alex , Green Jonathan 
Published: November 2022

Whale sharks (Rhincodon typus) frequently appear to interact or associate with other species, which vary depending on the community structure and the demographic of the whale sharks at each location globally. Here, we present the species sighted frequently around whale sharks in the Galapagos Archipelago, and reported by dive guides and scientists and also in earlier publications. These associated species include cetacean species: bottlenose dolphins (Tursiops truncatus), other shark species: silky sharks (Carcharhinus falciformis), Galapagos sharks (Carcharhinus galapagensis), scalloped hammerhead sharks (Sphyrna lewini), tiger sharks (Galeocerdo cuvier), and teleost fish species: remoras (Echeneis sp), yellowfin tuna (Thunnus albacares), almaco jacks (Seriola rivoliana), and black jacks (Caranx lugubris). The recording of interspecies associations and interactions may lead to better understanding of the natural history of whale sharks and can show important symbiotic relationships or interdependence between different species.