bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stellar versus Galactic: the intensity of cosmic rays at the evolving Earth and young exoplanets around Sun-like stars
Authors: Rodgers-Lee D , Taylor A M , Vidotto A A , Downes T P 
Published: March 2021

ABSTRACT
Energetic particles, such as stellar cosmic rays, produced at a heightened rate by active stars (like the young Sun) may have been important for the origin of life on Earth and other exoplanets. Here, we compare, as a function of stellar rotation rate (Ω), contributions from two distinct populations of energetic particles: stellar cosmic rays accelerated by impulsive flare events and Galactic cosmic rays. We use a 1.5D stellar wind model combined with a spatially 1D cosmic ray transport model. We formulate the evolution of the stellar cosmic ray spectrum as a function of stellar rotation. The maximum stellar cosmic ray energy increases with increasing rotation, i.e. towards more active/younger stars. We find that stellar cosmic rays dominate over Galactic cosmic rays in the habitable zone at the pion threshold energy for all stellar ages considered ($t_*=0.6\!-\!2.9\,$ Gyr). However, even at the youngest age, $t_*=0.6\,$ Gyr, we estimate that $\gtrsim \, 80$ MeV stellar cosmic ray fluxes may still be transient in time. At ∼1 Gyr when life is thought to have emerged on Earth, we demonstrate that stellar cosmic rays dominate over Galactic cosmic rays up to ∼4 GeV energies during flare events. Our results for t* = 0.6 Gyr (Ω = 4 Ω⊙) indicate that ≲GeV stellar cosmic rays are advected from the star to 1 au and are impacted by adiabatic losses in this region. The properties of the inner solar wind, currently being investigated by the Parker Solar Probe and Solar Orbiter, are thus important for accurate calculations of stellar cosmic rays around young Sun-like stars.
Disc versus wind accretion in X-ray pulsar GX 301-2
Authors: Liu Jiren , Ji Long , Jenke Peter A , Doroshenko Victor , Liao Zhenxuan , Li Xiaobo , Zhang Shuangnan , Orlandini Mauro , Ge Mingyu , Zhang Shu , Santangelo Andrea 
Published: March 2021

ABSTRACT
GX 301-2 provides a rare opportunity to study both disc and wind accretion in a same target. We report Insight-Hard X-ray Modulation Telescope observations of the spin-up event of GX 301-2 that happened in 2019 and compare with those of wind-fed state. The pulse profiles of the initial rapid spin-up period are dominated by one main peak, while those of the later slow spin-up period are composed of two similar peaks, as those of wind-fed state. These behaviours are confirmed by Fermi/Gamma-ray Burst Monitor data, which also show that during the rapid spin-up period, the main peak increases with luminosity up to 8 × 1037 erg s−1, but the faint peak remains almost constant. The absorption column densities during the spin-up period are ∼1.5 × 1023 cm−2, much less than those of wind-fed state at similar luminosity (∼9 × 1023 cm−2), supporting the scenario that most of material is condensed into a disc during the spin-up period. We discuss possible differences between disc and wind accretion that may explain the observed different trends of pulse profiles.
First star survivors as metal-rich halo stars that experienced supernova explosions in binary systems
Authors: Suda Takuma , Saitoh Takayuki R , Moritani Yuki , Matsuno Tadafumi , Shigeyama Toshikazu 
Published: March 2021

Abstract
The search for the first stars formed from metal-free gas in the universe is one of the key issues in astronomy because it relates to many fields, such as the formation of stars and galaxies, the evolution of the universe, and the origin of elements. It is not still clear if metal-free first stars can be found in the present universe. These first stars are thought to exist among extremely metal-poor stars in the halo of our Galaxy. Here we propose a new scenario for the formation of low-mass first stars that have survived until today and observational counterparts in our Galaxy. The first stars in binary systems, consisting of massive- and low-mass stars, are examined using stellar evolution models, simulations of supernova ejecta colliding with low-mass companions, and comparisons with observed data. These first star survivors will be observed as metal-rich halo stars in our Galaxy. We may have identified a candidate star in the observational database where elemental abundances and kinematic data are available. Our models also account for the existence in the literature of several solar-metallicity stars that have space velocities equivalent to the halo population. The proposed scenario demands a new channel of star formation in the early universe and is a supplementary scenario for the origin of the known metal-poor stars.
The distinct effect of titanium dioxide nanoparticles in primary and immortalized cell lines
Authors: Fayer Leonara , Zanette Rafaella S S , Siqueira Juliana T C , Oliveira Eduarda R , Almeida Camila G , Gern Juliana C , Sousa Saulo M , de Oliveira Luiz F C , Brandão Humberto M , Munk Michele 
Published: March 2021

Abstract
The titanium dioxide nanoparticles (NPs) have been applied to biomedical, pharmaceutical, and food additive fields. However, the effect on health and the environment are conflicting; thus, it has been reviewing several times. In this context, establishing standard robust protocols for detecting cytotoxicity and genotoxicity of nanomaterials became essential for nanotechnology development. The cell type and the intrinsic characteristics of titanium dioxide NPs can influence nanotoxicity. In this work, the cyto- and genotoxicity effects of standard reference material titanium dioxide NPs in primary bovine fibroblasts and immortalized Chinese hamster ovary epithelial (CHO) cells were determined and compared for the first time. Titanium dioxide NPs exposure revealed no cytotoxicity for primary bovine fibroblasts, while only higher concentrations tested (10 μg/ml) induce genotoxic effects in this cell model. In contrast, the lower concentrations of the titanium dioxide NPs cause the cyto- and genotoxic effects in CHO cells. Therefore, our finding indicates that the CHO line was more sensitive toward the effects of titanium dioxide NPs than the primary bovine fibroblast, which should be valuable for their environmental risk assessment.
The Lived Experiences of Nurses Working During the COVID-19 Pandemic
Authors: Robinson Ruthie , Stinson Cynthia Kellam 
Published: March 2021

Background
Previous research on nurses during pandemics has focused on nurses working in one facility or type of unit; this study focuses on nurses caring for COVID-19 patients in a variety of units in different sites across the United States.

Objective
The aim of this study was to understand the experiences of registered nurses working with hospitalized COVID-19 patients.

Methods
This study used a hermeneutic phenomenology design. Semistructured interviews via telephone were conducted and then transcribed verbatim. Colaizzi's method of analysis was used. Data saturation was achieved with 14 participants.

Results
Three major themes were evident. They were “the human connection,” “the nursing burden,” and “coping.” Subthemes were identified under each major theme.

Discussion
This study depicted nurses who are caring, empathetic, and resilient. They had many recommendations for fellow nurses, the public, and health care organizations.
Rheumatoid arthritis coexisting with ankylosing spondylitis
Authors: Zhang Yuanyuan , Feng Bo , Dong Jing , Zhong Yanyan , Wang Liqin , Zhao Lei 
Published: March 2021

Abstract
Coexisting rheumatoid arthritis (RA) and ankylosing spondylitis (AS) in the same patient is often thought to be rare, and thus misdiagnosis is common. The aim of our study was to describe the main characteristics of RA coexisting with AS in patients with delayed diagnoses and improve awareness of the disease association.
Between 2012 and 2018, data from 22 patients who had RA and AS (RA/AS) were retrospectively reviewed. All patients had a history of delayed diagnosis for RA or AS. The clinical features and radiographic changes of RA and AS patients were obtained at baseline and after 2 years. Disease activity score 28 (DAS28) or bath ankylosing spondylitis disease activity index (BASDAI) were used as outcome measures. The mean age at the time of diagnosis of RA/AS was 51.8 years, while the mean duration of diagnostic delay was 5.5 years. Middle-aged women were the most common subgroup among the RA/AS cohort. The common clinical manifestations were systemic, symmetric, peripheral, and axial arthritis. The erythrocyte sedimentation rate and C-reactive protein levels in RA/AS patients were elevated at the time diagnosis of RA/AS. The typical radiologic changes for the 2 diseases coexisted in RA/AS patients. The DAS28 and BASDAI scores at the 2-year follow-up evaluation were lower than the initial assessment.
Coexisting RA and AS is often misdiagnosed for many years; a lack of recognition of RA and AS together is one of the most common reasons. Systemic, symmetric, peripheral, and axial arthritis in middle-aged women were the most frequent presentations at onset.
Efficacy of rivaroxaban for the treatment of Chinese patients with acute pulmonary embolism
Authors: Wang Lei , Jiang Shuang , Li Chao , Xu Zhi , Chen Ying 
Published: March 2021

Abstract
Pulmonary embolism (PE) is a life-threatening disease, which accounts for the major type of venous thromboembolism. Currently, there is limited understanding and management for PE. Rivaroxaban is reported to treat patients with PE. However, there is still insufficient evidence on rivaroxaban for the treatment of Chinese patients with acute PE. Thus, this retrospective study investigated the benefits and safety of rivaroxaban for Chinese patients with acute PE.
A total of 72 Chinese patient cases with acute PE were analyzed in this study. Of these, 36 cases who received rivaroxaban mono-therapy were assigned to the treatment group, while the remaining 36 cases who received standard therapy were assigned to the control group. The benefits were assessed by the duration of hospital stay, treatment satisfaction, and safety.
After treatment, rivaroxaban mono-therapy showed better benefits in decreasing the duration of hospital stay (P < .01), increasing treatment satisfaction (P < .01), and reducing mild bleeding (P = .02) in Chinese patients with acute PE, than standard therapy.
The results of this study indicated that rivaroxaban may provide more benefits than the standard therapy for Chinese patients with acute PE. Future studies are still needed to warrant the current results.
Prognostic implications of an autophagy-based signature in colorectal cancer
Authors: Wang Liangbin , Jiang Xinlei , Zhang Xingguo , Shu Peng 
Published: March 2021

Abstract

Background:
The heterogeneity of colorectal cancer (CRC) poses a significant challenge to the precise treatment of patients. CRC has been divided into 4 consensus molecular subtypes (CMSs) with distinct biological and clinical characteristics, of which CMS4 has the mesenchymal identity and the highest relapse rate. Autophagy plays a vital role in CRC development and therapeutic response.

Methods:
The gene expression profiles collected from 6 datasets were applied to this study. Network analysis was applied to integrate the subtype-specific molecular modalities and autophagy signature to establish an autophagy-based prognostic signature for CRC (APSCRC).

Results:
Network analysis revealed that 6 prognostic autophagy genes (VAMP7, DLC1, FKBP1B, PEA15, PEX14, and DNAJB1) predominantly regulated the mesenchymal modalities of CRC. The APSCRC was constructed by these 6 core genes and applied for risk calculation. Patients were divided into high- and low-risk groups based on APSCRC score in all cohorts. Patients within the high-risk group showed an unfavorable prognosis. In multivariate analysis, the APSCRC remained an independent predictor of prognosis. Moreover, the APSCRC achieved higher prognostic power than commercialized multigene signatures.

Conclusions:
We proposed and validated an autophagy-based signature, which is a promising prognostic biomarker of CRC patients. Further prospective studies are warranted to test and validate its efficiency for clinical application.
Trends in the incidence and prevalence of end-stage renal disease with hemodialysis in entire Korean population
Authors: Choi Hong Sang , Han Kyung-Do , Oh Tae Ryom , Suh Sang Heon , Kim Minah , Kim Chang Seong , Bae Eun Hui , Ma Seong Kwon , Kim Soo Wan 
Published: March 2021

Abstract
Data on the overall epidemiology and temporal trends of end-stage renal disease (ESRD) requiring hemodialysis in Korea are scarce. We aimed to estimate the prevalence and incidence of ESRD requiring hemodialysis in Korea between 2002 and 2017.
Using the National Health Insurance Service database, we analyzed data from the entire Korean population between 2002 and 2017. Hemodialysis patients were identified using rare incurable disease codes (V001) or prescription of medical fee codes of hemodialysis (O7020 and O7021). We only included patients who had been maintained on hemodialysis for more than 90 days from the date of dialysis initiation, to exclude patients who required short-term dialysis for acute kidney injury, conversion to peritoneal dialysis, or kidney transplantation.
During the 16-year follow-up, the number of hemodialysis patients in Korea has steadily increased from 11,215 in 2002 to 67,486 in 2017. The mean age of these patients has gradually increased from 55.57 ± 13.31 years in 2002 to 62.13 ± 13.23 years in 2017. In 2017, the crude prevalence rate of hemodialysis was 1303.4 per million population. Overall, the number of men tended to be somewhat higher than that of women, and the proportion of men increased slightly from 55.56% in 2002 to 58.45% in 2017. The proportion of diabetic patients increased rapidly from 23.84% to 47.84%, and the percentage of dyslipidemic patients rose from 18.9% to 86.7%. The number of incident hemodialysis patients increased significantly from 4406 in 2003 to 12,134 in 2014, and then decreased to 8090 in 2017. In the incident cases of hemodialysis, the observed increase in the proportion of male patients and in diabetes and dyslipidemia were similar to that of prevalent patients. The more recent era of hemodialysis initiation, the better 5-year survival rates were observed.
The prevalence and incidence of hemodialysis in Korea gradually increased between 2002 and 2017. The proportion of men, and patients with diabetes and dyslipidemia requiring hemodialysis also increased continuously. The survival rate of hemodialysis patients was gradually improving. These findings may serve as a reference for future epidemiological studies on hemodialysis in Korea.
The systemic treatment of uterine leiomyosarcomas
Authors: Kyriazoglou Anastasios , Liontos Michalis , Ntanasis-Stathopoulos Ioannis , Gavriatopoulou Maria 
Published: March 2021

Abstract

Background:
Uterine leiomyosarcomas are rare malignant mesenchymal tumors. The systemic treatment of these tumors includes chemotherapy and radiotherapy. However, there are still a lot of unanswered questions regarding the ideal therapeutic approach.

Methods:
We have conducted a systematic review of the treatment strategies of uterine leiomyosarcomas for the last ten years.

Results:
Adjuvant chemotherapy is still a matter of dilemma. Doxorubicin based chemotherapy or the combination of Gemcitabine-Docetaxel are the regimens of choice for the first line setting. Beyond the first line, there are several options;, including chemotherapy, targeted therapy, and recently efforts of introducing immunotherapy to the therapeutic armamentarium of clinicians treating uterine leiomyosarcomas.

Conclusions:
Despite the efforts of the clinicians dealing with uterine leiomyosarcomas, the optimal therapeutic algorithm is yet to be described.
The Supply and Distribution of the Preventive Medicine Physician Workforce
Authors: Ricketts Thomas C. , Porterfield Deborah S. , Miller Randall L. , Fraher Erin P. 
Published: March 2021

Context:
Preventive medicine physicians work at the intersection of clinical medicine and public health. A previous report on the state of the preventive medicine workforce in 2000 revealed an ongoing decline in preventive medicine physicians and residents, but there have been few updates since.

Objective:
The purpose of this study was to describe trends in both the number of board-certified preventive medicine physicians and those physicians who self-designate preventive medicine as a primary or secondary specialty and examine the age, gender distribution, and geographic distribution of this workforce.

Design:
Analysis of the supply of preventive medicine physicians using data derived from board certification files of the American Board of Preventive Medicine and self-designation data from the American Medical Association Masterfile.

Setting:
The 50 US states and District of Columbia.

Participants:
Board-certified and self-designated preventive medicine physicians in the United States.

Main Outcome Measures:
Number, demographics, and location of preventive medicine physicians in United States.

Results:
From 1999 to 2018, the total number of physicians board certified in preventive medicine increased from 6091 to 9270; the number of self-identified preventive medicine physicians has generally decreased since 2000, with a leveling off in the past 4 years matching the trend of preventive medicine physicians per 100 000 population; there is a recent increase in women in the specialty; the practice locations of preventive medicine physicians do not match the US population in rural or micropolitan areas; and the average age of preventive medicine physicians is increasing.

Conclusions:
The number of preventive medicine physicians is not likely to match population needs in the United States in the near term and beyond. Assessing the preventive medicine physician workforce in the United States is complicated by difficulties in defining the specialty and because less than half of self-designated preventive medicine physicians hold a board certification in the specialty.
Outcomes of an Intervention to Increase Physicians Underrepresented in Medicine in Occupational Medicine Training
Authors: Green-McKenzie Judith , Savul Sajjad 
Published: March 2021

Context:
Diversity in the US physician workforce is important. Physicians Underrepresented in Medicine (UIM) are more likely to serve poor, uninsured, and vulnerable populations.

Objective:
To increase the number of UIM physicians in Occupational Medicine.

Program:
An Inclusion and Diversity Committee, consisting of the program director, trainees, and graduates, was created with the goal of recruiting and developing UIM residents and increasing Occupational and Environmental Medicine awareness. Outreach to UIM residents and medical students at local, regional, and national meetings, creation and distribution of descriptive brochures, and supervised 1-day observerships were some of the interventions.

Results:
Only 4 Underrepresented Minorities physicians out of 65 (6%) graduated during the first decade of the program 1997-2007; this increased to (16/70) 23% during the following decade subsequent to establishing the Inclusion and Diversity Committee.

Conclusion:
A multifaceted strategic approach can help increase UIM physician participation in graduate training programs, helping address health equity.
Assessment of Bone Mineral Density From a Computed Tomography Topogram of Photon-Counting Detector Computed Tomography—Effect of Phantom Size and Tube Voltage
Authors: Euler André , Nowak Tristan , Bucher Brian , Eberhard Matthias , Schmidt Bernhard , Flohr Thomas G. , Frey Diana , Distler Oliver , Alkadhi Hatem 
Published: March 2021

Purpose
The aim of this study was to assess the accuracy and impact of different sizes and tube voltages on bone mineral density (BMD) assessment using a computed tomography (CT) topogram acquired with photon-counting detector CT in an osteopenic ex vivo animal spine.

Materials and Methods
The lumbar back of a piglet was used to simulate osteopenia of the lumbar spine. Five fat layers (each with a thickness of 3 cm) were consecutively placed on top of the excised spine to emulate a total of 5 different sizes. Each size was repeatedly imaged on (A) a conventional dual-energy x-ray absorptiometry scanner as the reference standard, (B) a prototype photon-counting detector CT system at 120 kVp with energy thresholds at 20 and 70 keV, and (C) the same prototype system at 140 kVp with thresholds at 20 and 75 keV. Material-specific data were reconstructed from spectral topograms for B and C. Bone mineral density was measured for 3 lumbar vertebrae (L2–L4). A linear mixed-effects model was used to estimate the impact of vertebra, imaging setup, size, and their interaction term on BMD.

Results
The BMD of the lumbar spine corresponded to a T score in humans between −4.2 and −4.8, which is seen in osteoporosis. Averaged across the 3 vertebrae and 5 sizes, mean BMD was 0.56 ± 0.03, 0.55 ± 0.02, and 0.55 ± 0.02 g/cm2 for setup A, B, and C, respectively. There was no significant influence of imaging setup (P = 0.7), simulated size (P = 0.67), and their interaction term (both P > 0.2) on BMD. Bone mineral density decreased significantly from L2 to L4 for all 3 setups (all P < 0.0001). Bone mineral density was 0.59 ± 0.01, 0.57 ± 0.01, and 0.52 ± 0.02 g/cm2 for L2, L3, and L4, respectively, for setup A; 0.57 ± 0.02, 0.55 ± 0.01, and 0.53 ± 0.01 g/cm2 for setup B; and 0.57 ± 0.01, 0.55 ± 0.01, and 0.53 ± 0.01 g/cm2 for setup C.

Conclusion
A single CT topogram acquired on photon-counting detector CT with 2 energy thresholds enabled BMD quantification with similar accuracy compared with dual-energy x-ray absorptiometry over a range of simulated sizes and tube voltages in an osteopenic ex vivo animal spine.
High-Fidelity Patient Simulation Incorporated Into a Flipped Classroom Improves Students' Long-Term Knowledge Retention of Acute Organophosphorus Pesticide Poisoning
Authors: Zheng Ziyu , Liao Jinli , Zeng Lijin , Tang Hao , Li Hui , Liu Zhihao , Zhan Hong , Yang Zhen , Xiong Yan , Yuan Shiwen 
Published: March 2021

Introduction
The flipped classroom (FC) approach and high-fidelity patient simulation (HFPS) training have shown promising effects in short-term acquisition or long-term retention of knowledge in medical education. In this study, we aimed to explore the incorporation of HFPS into the FC and the impact on the long-term (3 months after classes) knowledge retention of medical undergraduate students learning about acute organophosphorus pesticide poisoning (AOPP).

Methods
Eighty-two fifth-year medical students were randomly divided into an HFPS group (HG, n = 40) and an FC group (FG, n = 42). A postclass quiz and preinternship quiz were performed to assess the short-term knowledge acquisition and long-term (3 months after classes) knowledge retention of both groups of students. Feedback questionnaires were administered immediately after the class and before the internship to assess the students' self-perceived competency.

Results
In the postclass quiz, the scores achieved by the students from the HG and FG were 15.58 ± 2.69 and 14.62 ± 2.19, respectively. No significant difference was found between the 2 groups (P = 0.19). In the preinternship quiz, the scores achieved by the students from the HG (14.50 ± 2.16) were significantly higher than those achieved by the students from the FG (11.40 ± 2.07, P < 0.001). There was no significant difference between the postclass quiz and preinternship quiz scores achieved by the HG students (P = 0.05). However, scores in the preinternship quiz showed a significant decline compared with the postclass quiz for the FG students (P < 0.001). Students in the HG gave significantly higher scores for self-perceived confidence in dealing with AOPP patients in the forthcoming internship on the postclass and preinternship questionnaires.

Conclusions
The incorporation of HFPS into the FC approach could improve students' long-term knowledge retention of AOPP and enhance their confidence in caring for these patients in their internship.