bluuebunny/crossref_metadata_2025_split huggingface dataset:
Is There an Enormous Cold Front at the Virial Radius of the Perseus Cluster?
Authors: Walker S. A. , Mirakhor M. S. , ZuHone J. , Sanders J. S. , Fabian A. C. , Diwanji P. 
Published: April 2022

Abstract
We present new XMM-Newton observations extending the mosaic of the Perseus cluster out to the virial radius to the west. Previous studies with ROSAT have reported a large excess in surface brightness to the west, possibly the result of large-scale gas sloshing. In our new XMM-Newton observations we have found two X-ray surface brightness edges at 1.2 and 1.7 Mpc to the west. The temperature measurements obtained with Suzaku data indicate that the temperature increases sharply at each edge, consistent with what would be expected from cold fronts. However the the XMM-Newton data are affected by stray light, which at present is a poorly understood source of systematic error that can also lead to curved features in X-ray images. To test our results, we compared our X-ray surface brightness profile with that obtained from ROSAT PSPC data. While the edge at 1.2 Mpc is confirmed by ROSAT PSPC, the ROSAT data quality is insufficient to confirm the outer edge at 1.7 Mpc. Further observations with future X-ray telescopes will be needed to confirm the existence of the outer edge at 1.7 Mpc. By comparing with numerical simulations, we find that these large cold fronts require a large impact parameter, and low-mass ratio mergers that can produce fast gas motions without destroying the cluster core.
Quantifying Chemical and Kinematical Properties of Galactic Disks
Authors: Hu 胡 Guozhen 国真 , Shao 邵 Zhengyi 正义 
Published: April 2022

Abstract
We aim to quantify the chemical and kinematical properties of Galactic disks with a sample of 119,558 giant stars having abundances and 3D velocities taken or derived from the APOGEE DR17 and Gaia EDR3 catalogs. A Gaussian mixture model is employed to distinguish the high-α and low-α sequences along the metallicity by simultaneously using chemical and kinematical data. Four disk components are identified and quantified; they are named the hαmp, hαmr, lαmp, and lαmr disks and correspond to the high-α or low-α, and metal-poor or metal-rich properties. Combined with the spatial and stellar-age information, we confirm that they are well interpreted by the two-infall formation model. The first infall of turbulent gas quickly forms the hot and thick hαmp disk with consequent thinner hαmr and lαmr disks. Then the second gas accretion forms a thinner and outermost lαmp disk. We find that the inside-out and upside-down scenario does not only satisfy the overall Galactic disk formation of these two major episodes but is also presented in the formation sequence of the three inner disks. Importantly, we reveal the inverse age–[M/H] trend of the lαmr disk, which means its younger stars are more metal-poor, indicating that the rejuvenated gas from the second accretion gradually dominates later star formation. Meanwhile, the recently formed stars converge to [M/H] ∼ −0.1 dex, demonstrating a sufficient mixture of gas from two infalls.
Simple Analytic Formula Relating the Mass and Spin of Accreting Compact Objects to Their Rapid X-Ray Variability
Authors: Török Gabriel , Kotrlová Andrea , Matuszková Monika , Klimovičová Kateřina , Lančová Debora , Urbancová Gabriela , Šrámková Eva 
Published: April 2022

Abstract
Following the previous research on epicyclic oscillations of accretion disks around black holes (BHs) and neutron stars (NSs), a new model of high-frequency quasiperiodic oscillations (QPOs) has been proposed, so-called cusp torus (CT) model, which deals with oscillations of fluid in marginally overflowing accretion tori (i.e., tori terminated by cusps). According to preliminary investigations, the model provides better fits of the NS QPO data compared to the relativistic precession (RP) model. It also implies a significantly higher upper limit on the Galactic microquasar BH spins. A short analytic formula has been noticed to well reproduce the model’s predictions on the QPO frequencies in Schwarzschild spacetimes. Here we derive an extended version of this formula that applies to rotating compact objects. We start with the consideration of Kerr spacetimes and derive a formula that is not restricted to a particular specific angular momentum distribution of the inner accretion flow, such as a Keplerian or constant one. Finally, we consider Hartle–Thorne spacetimes and include corrections implied by the NS oblateness. For a particular choice of a single parameter, our relation provides frequencies predicted by the CT model. For another value, it provides frequencies predicted by the RP model. We conclude that the formula is well applicable to rotating oblate NSs and both models. We briefly illustrate the application of our simple formula on several NS sources and confirm the expectation that the CT model is compatible with realistic values of the NS mass and provides better fits of data than the RP model.
The Primary Proton Spectrum of the Hadronic PeVatron Candidate HAWC J1825-134
Authors: Dzhatdoev Timur , Podlesnyi Egor , Vaiman Igor 
Published: April 2022

Abstract
The γ-ray spectrum of the source HAWC J1825-134 measured with the High Altitude Water Cherenkov (HAWC) observatory extends beyond 200 TeV without any evidence for a steepening or cutoff. There are some indications that the γ-rays detected with HAWC were produced by cosmic-ray protons or nuclei colliding with the ambient gas. Assuming primary protons, we inquire which shape of the primary proton spectrum is compatible with the HAWC measurements. We find that the primary proton spectrum with the power-law shape of γ

p
= 2.2 and the cutoff energy E

c−p
> 500 TeV describes the data well. However, much harder spectra with γ

p
down to 1.3 and E

c−p
as low as 200 TeV also do not contradict the HAWC measurements. The former option might be realized if the accelerator is inside or very near to the γ-ray production zone. The latter option is viable for the case of a cosmic-ray source that effectively confines low-energy (E

p
< 10 TeV) accelerated protons. Using publicly available data of the Fermi-LAT space γ-ray telescope, we derive upper limits on the intensity of the HAWC J1825-134 source in the 1 GeV–1 TeV energy range. We show that the account of these upper limits drastically changes the interpretation: only hard (γ

p
< 1.7) spectra describe the combined HAWC and Fermi-LAT data sets well.
Magnetic Switchback Occurrence Rates in the Inner Heliosphere: Parker Solar Probe and 1 au
Authors: Pecora Francesco , Matthaeus William H. , Primavera Leonardo , Greco Antonella , Chhiber Rohit , Bandyopadhyay Riddhi , Servidio Sergio 
Published: April 2022

Abstract
The subject of switchbacks, defined either as large angular deflections or polarity reversals of the magnetic field, has generated substantial interest in the space physics community since the launch of the Parker Solar Probe (PSP) in 2018. Previous studies have characterized switchbacks in several different ways and have been restricted to data available from the first few orbits. Here, we analyze the frequency of occurrence of switchbacks per unit distance for the first full eight orbits of PSP. In this work, events that reverse the sign of the magnetic field relative to a regional average are considered switchbacks. A significant finding is that the rate of occurrence falls off sharply approaching the Sun near 0.2 au (40 R
⊙) and rises gently from 0.2 au outward. The analysis is varied for different magnetic field cadences and for different local averages of the ambient field, confirming the robustness of the results. We discuss implications for the mechanisms of switchback generation. A publicly available database has been created with the identified reversals.
Limiting Flux versus Redshift as a Flag of New Physics
Authors: Loeb Abraham 
Published: April 2022

Abstract
I show that General Relativity sets an absolute upper limit on the energy flux observed from a cosmological source as a function of its redshift. Detecting a brighter source in gravitational waves, neutrinos or light, would flag new physics. The derived flux limit can also be used to determine the maximum redshift possible for any source with an unknown origin.
The Increase of Knowledge, Attitude, and Practice of Husbands toward the Prenatal Care of their Wives Using the Illustrations Having the Local Cultural Nuance
Authors: Sinaga Siti Nurmawan , Siagian Albiner , Nurmaini Nurmaini , Badaruddin Badaruddin 
Published: April 2022

BACKGROUND: The role of husbands in maternal health during pregnancy is crucial and is related to the high maternal mortality rate in Indonesia. In spite of that, the effort to involve husbands in the maternal health program is still low.

AIM: This paper aims to explain the results of the effort to produce learning assisting tools in a form of an illustration having local cultural nuance that can be used to do intervention of health education to increase the participation of husbands in maternal health.

METHODS: The research was conducted in Silaen Village, Silaen District in Toba Regency, North Sumatera Province. To make the teaching materials, interviews and focus group discussions were conducted for the village community figures, the village midwives, the pregnant women, and their husbands. After illustrations were made, the trial was conducted to 10 pairs of husbands and pregnant wives.

RESULTS: The illustrations made accommodating the role of husbands in maternal health can increase the knowledge, attitude, and practice (KAP) of husbands, including the KAP of their wives. The biggest increase happening in the attitude component (p < 0.05).

CONCLUSION: The educational method using an illustration adopting local culture is important to become one of the education teaching alternatives in the effort to improve husband’s KAP.
Factors Associated with Anxiety Scores in Patients with Stable Angina Pectoris in Cardiology Outpatient Clinic of Universitas Sumatera Utara Hospital
Authors: Ginting Silvana R. R. , Loebis Bahagia , Camellia Vita 
Published: April 2022

Introduction: Stable angina pectoris is of great interest to health care workers because of the high levels of anxiety observed in patients following a coronary event. This study aims to investigate factors associated with anxiety scores in patients with stable angina pectoris.
Methods: This cross-sectional study was conducted from November to December 2020. Subjects were patients diagnosed with stable angina pectoris in the Cardiology outpatient clinic of Universitas Sumatera Utara Hospital. Signed the informed consent were subjected to history taking, and structured interviews then were asked to fill out the HADS questionnaire.
Results: A total of 200 study subjects were obtained. The majority of the subjects, 110 (55%) subjects, were women. Of all subjects, 105 (52.5%) subjects were married. The majority of study subjects were employed (61.5%), had >9 years education (88%), non-smokers (70.5%), had comorbidities (73.5%) and had a family history of the disease (64%). The median age was 53 years (min 50, max 55 years). The median value of the length of illness was seven years (min 1 year, max 12 years). The median value of body mass index was 24.16 (min 20.11, max 30.59).
Conclusion: Age, marital relationship, occupation, smoking status, comorbidities, family history of the disease, and body mass index were found to be associated with anxiety scores in patients with stable angina pectoris.
Relations de services
Authors: Caroly Sandrine , Weill-Fassina Annie 
Published: April 2022

Résumé L’évolution des activités de services des guichetiers et des conseillers funéraires est marquée par trois caractéristiques : une augmentation de la population précaire rendant plus complexe le traitement des dossiers, une mutation vers l’informatique, une pression temporelle liée aux contraintes économiques. Les mutations économiques dont l’ouverture à la concurrence, conduisent les entreprises de pompes funèbres et la Poste à redéfinir les missions des salariés en relation de service. Pour les conseillers funéraires, on observe une professionnalisation croissante accompagnée par une augmentation des contraintes réglementaires. Il devient notamment un spécialiste de réseaux d’acteurs professionnels. Pour les guichetiers de la Poste, sont introduites de nouvelles contraintes commerciales qui modifient les relations avec la clientèle. Le guichetier devient polyvalent : il doit prendre en charge simultanément des fonctions administrative, financière et commerciale tout en conseillant le client. La qualité de service devient un objet de transaction entre l’agent et le client. Les objectifs de rentabilité et de qualité relationnelle avec la clientèle peuvent être contradictoires dans la réalisation de l’activité des agents. Ce contexte de travail invite à questionner les régulations individuelles et collectives mises en œuvre par les agents pour gérer ces contradictions.
Intravenous iron supplementation treats anemia and reduces blood transfusion requirements in patients undergoing coronary artery bypass grafting—A prospective randomized trial
Authors: Shokri Hoda , Ali Ihab 
Published: April 2022

Study Objective:
Preoperative anemia results in two- to sixfold increased incidence of perioperative blood transfusion requirements and reduced postoperative hemoglobin (Hb) level. This prospective study was designed to investigate the effect of preoperative intravenous infusion of iron on Hb levels, blood transfusion requirements, and incidence of postoperative adverse events in patients undergoing coronary artery bypass grafting.

Design:
Prospective randomized trial.

Setting:
Academic university hospital.

Patients:
Eighty patients (52–67 years old) underwent coronary artery bypass grafting and received either iron therapy or saline infusion preoperatively.

Interventions:
Patients were randomly allocated to iron or placebo groups. In the iron group, patients received a single intravenous dose of ferric carboxymaltose (1000 mg in 100 mL saline) infused slowly over 15 min 7 days before surgery. In placebo group, patients received a single intravenous dose of saline (100 mL saline) infused slowly over 15 min 7 days before surgery.

Measurements:
Patients were followed up with regards to incidence of anemia, Hb level on admission, preoperatively, postoperatively, 1 week and 4 weeks after discharge, aortic cross-clamp time, the number of packed red blood cells (pRBCs) units, the percentage of reticulocytes pre–postoperatively and 1 week later, hospital stay and intensive care unit (ICU) stay length, and the incidence of postoperative complications.

Main Results:
Iron therapy was associated with lower incidence of anemia 4 weeks after discharge (P < 0.001). Hb level was significantly higher in the iron group compared to the placebo group preoperatively and postoperatively, and 4 weeks after discharge (P < 0.001). Iron therapy resulted in shorter hospital and ICU stay (P < 0.001) and shorter aortic cross-clamp time, reduced pRBCs requirements postoperatively. Percentage of reticulocytes was significantly higher in placebo group than in iron group postoperatively and 1 week after discharge and the incidence of postoperative complications was similar to the placebo group.

Conclusions:
Preoperative IV iron infusion is a safe and feasible way to manage preoperative anemia. Preoperative administration of IV iron is associated with a higher postoperative Hb level, shorter hospital and ICU stay, and reduced perioperative red blood cell transfusion requirements with insignificant difference in incidence of postoperative complications.
Comparison of Effects of Sevoflurane Versus Propofol on Left Ventricular Longitudinal Global and Regional Strain in Patients Undergoing On-Pump Coronary Artery Bypass Grafting
Authors: Chennakeshavallu G N , Gadhinglajkar Shrinivas , Sreedhar Rupa , Babu Saravana , Sankar Sruthi , Dash Prasanta Kumar 
Published: April 2022

Background:
Assessment of myocardial deformation by quantifying peak systolic longitudinal strain (PSLS) is a sensitive and robust index to detect subclinical myocardial dysfunction. We hypothesize that sevoflurane by virtue of anesthetic preconditioning preserves myocardial function better than propofol.

Aims:
The authors have assessed the effects of sevoflurane and propofol on global longitudinal strain (GLS) as a primary outcome in patients undergoing on-pump coronary artery bypass grafting. Our secondary aim was to assess the pattern of regional distribution of segmental PSLS between the groups.

Materials and Methods:
Fifty patients with normal left ventricular function undergoing coronary artery bypass grafting were analyzed in this prospective observational study. Consecutive patients received either propofol (P) or sevoflurane (S) anesthesia.

Measurements:
Trans-esophageal echocardiographic images (mid-esophageal four-chamber, two-chamber, and three-chamber (long-axis)) were recorded during the precardiopulmonary bypass (CPB) and post-CPB period. Strain analysis (GLS/segmental PSLS) was done offline by investigators blinded to the study. The inotropic score, duration of inotropic support, and mechanical ventilation required were recorded.

Results:
Following cardiopulmonary bypass and coronary revascularization, GLS reduced significantly in both the groups (P < 0.05). In the S-group, significant reduction in segmental strain was observed only in apical segments including apex, whereas in P-group significant reduction in segmental strain was seen in mid- and apical segments. The postoperative VIS, duration of inotropes/vasopressor required, and mechanical ventilation were similar in both the groups.

Conclusions:
There are no significant differences in global left ventricular function as assessed by GLS between patients anesthetized with sevoflurane or propofol. However, regional PSLS was better preserved in the S-group compared to P-group.
Infection Prevention and Control
Authors: Ochie Casmir Ndubuisi , Aniwada Elias C. , Uchegbu Chukwueloka K. , Asogwa Thaddeus C. , Onwasoigwe Chika N. 
Published: April 2022

Introduction:
Administrative supervision of infection prevention and control (IPC) is the most important aspect of IPC/hazard controls. The practice, uptake, and compliance to IPC is a documented, cost-effective method of interrupting the infection transmission pathways. Poor or nonadherence to this has led to disabilities and loss of lives among health-care workers, especially in the face of emerging and re-emerging infections. The present study evaluated the practice of IPC as well as its uptake and administrative control among the primary health-care workers in Enugu metropolis, Southeast Nigeria.

Methodology:
This was an analytical cross-sectional study using semi-structured self-administered questionnaires and an observation checklist. Eligible health-care workers (HCWs) were selected using simple random sampling from ten primary health-care (PHC) facilities. Chi-square test was used to examine associations of interest. Binary logistic regression was employed to identify predictors of good IPC practices.

Results:
Three hundred eligible health-care workers participated in this study. More than a fifth (n = 65, 21.7%) of HCWs exhibited good practice of IPC measures. Correct practice of handwashing was noted among 275 (95.7%) respondents. Majority (n = 224, 74.7%) reported recapping of needles and engaged in unsanitary disposal of health-care wastes (n = 257, 85.7%). The prevalence of needlestick injuries 3 months prior to the study period was 53.3% (n = 160). Majority of those sampled reported a lack of IPC committee (n = 220, 73.3%), conspicuous signage to aid movement (n = 230, 76.7%), and an IPC policy (n = 217, 72.3%) in their respective centers. Identified predictors of good practice of IPC were age <40 years (adjusted odds ratios [AORs] 0.57; 95% confidence interval [CI] 0.38–0.57), being a community health extension worker or community health officer (AOR 3.76; 95% CI 1.56–9.03), and working for <20 years (AOR 5.10;95% CI 5.00-5.73).

Conclusion:
Poor practice of IPC and poor compliance to administrative control among PHC workers, in addition to lack of administrative facilities, remains a great challenge. There is an urgent need for capacity building on IPC and administrative support to reverse this trend.
Pathological findings in COVID-19
Authors: Kyada Hetal C. , Bhalara Rohit V. , Vadgama Divyesh K. , Varu Pratik R. , Trangadia Mahesh M. , Manvar Prince J. , Bhuva Shailesh D. 
Published: April 2022

Background & objectives
Autopsy study has been considered the gold standard method for studying the effects of any disease on the body. Since COVID-19 is a novel disease, autopsy is crucial to understand its pathophysiology. This study was conducted to analyze the microscopic and macroscopic findings of various organs in COVID-19 and to associate those findings with clinical observations and laboratory findings.

Methods
Conventional invasive autopsies were performed on 33 patients with COVID-19 from September 7, 2020 to December 23, 2020. All the organs were removed by routine dissection techniques and preserved in 10 per cent formalin. The tissues were processed and stained according to standard practices using haematoxylin-eosin (H & E) and periodic acid-schiff (PAS) stain.

Results
The study included 28 males and 5 females with a median age of 61 yr (range 30-90 yr). Massive pulmonary oedema and thrombi in the lungs were the characteristic features macroscopically. On microscopic examination, diffuse alveolar damage in the exudative/proliferative phase was found in 29 (87.88%) cases. Among the other notable microscopic findings were bronchopneumonia and lung abscesses due to secondary bacterial infection (n=17, 51.52%), acute tubular injury (n=21, 63.64%) and thrombi in the lungs, heart, and kidneys.

Interpretation & conclusions
COVID-19 primarily affected the respiratory and the renal systems in the vast majority of severely affected patients in our study. We also found signs of hypercoagulability, as evidenced by widespread thrombi in multiple organs, along with a raised d-dimer level and a hyperinflammatory state manifested by elevated inflammatory markers. Our autopsy findings and altered laboratory investigations support the role of immune-mediated cellular injury along with direct virus-mediated cellular damage.