bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of radiative feedback on the initial mass function of metal-poor stars
Authors: Chon Sunmyon , Hosokawa Takashi , Omukai Kazuyuki , Schneider Raffaella 
Published: April 2024

ABSTRACT
The stellar initial mass function (IMF) in the early universe is essential to understand the formation of ancient galaxies. To this end, we conduct a series of long-term radiation hydrodynamic simulations following star cluster formation, varying the metallicity from Z/Z⊙ = 10−4 to 1. We particularly consider the effects of protostellar radiative feedback, which modify the exact shape of the IMF and determine the star formation efficiency (SFE), i.e. the ratio between the mass in stars and the initial gas mass in the parental cloud. Our results show that the IMF changes from a Salpeter-type to a top-heavy function as the metallicity decreases. When Z/Z⊙ ≲ 10−2, the IMF becomes log-flat and distinct from a Salpeter-like IMF. Stellar feedback is effective in shaping both the low- and high-mass ends of the IMF. Heating of dust grains by stellar radiation suppresses small-scale fragmentation and reduces the number of low-mass stars with M* ≲ 1 M⊙ at all metallicities. The ionizing radiation hinders the growth of massive stars, steepening the slope of the IMF at the high-mass end. The resulting feedback is more effective at lower metallicity, and star formation is regulated by stellar radiative feedback, with the SFE decreasing with decreasing metallicity. We suggest that the unexpectedly large number of UV-bright galaxies at z &gt; 10 reported by JWST observations can be explained by considering star cluster formation at Z/Z⊙ ∼ 10−2 or 10−3, where the IMF is top-heavy, but the SFE is not too low due to stellar feedback.
Using ZDI maps to determine magnetic forces and torques at the photospheres of early-type stars
Authors: MacDonald James , Natan Tali , Petit Véronique , Kochukhov Oleg , Shultz Matthew E 
Published: April 2024

ABSTRACT
We use the magnetic field components measured by Zeeman Doppler imaging (ZDI) to calculate the stellar surface force and torque due to magnetic stresses for the fast rotators σ Ori E, 36 Lyn, and CU Vir, and the slow rotator τ Sco. If we assume the stars have spherical photospheres, the estimated torques give spin-down time-scales no larger than 7 × 105 yr. For σ Ori E, the predicted spin-down time-scale, ≃ 6000 yr, is much less than the observationally measured time-scale of ≃ 106 yr. However, for CU Vir, we find that the spin-down time-scale from its ZDI map is 7 × 105 yr in good agreement with its average rate of spin-down from 1960 to 2010.
With the exception of τ Sco, the net force due to magnetic stresses at the stellar surface are large compared to the surface-integrated pressure. We discuss possible reasons for the large values of the forces (and torques), and suggest that the likely explanation is that rotation and the magnetic stresses create significant departures from spherical symmetry.
The metallicity gradients of star-forming regions store information of the assembly history of galaxies
Authors: Jara-Ferreira F , Tissera P B , Sillero E , Rosas-Guevara Y , Pedrosa S E , De Rossi M E , Theuns T , Bignone L 
Published: April 2024

ABSTRACT
The variations in metallicity and spatial patterns within star-forming regions of galaxies result from diverse physical processes unfolding throughout their evolutionary history, with a particular emphasis on recent events. Analysing MaNGA and EAGLE galaxies, we discovered an additional dependence of the mass–metallicity relation (MZR) on metallicity gradients (∇(O/H)). Two regimes emerged for low- and high-stellar mass galaxies, distinctly separated at approximately M⋆ &gt; 109.75$\rm{M}_{\odot}$. Low-mass galaxies with strong positive ∇(O/H) appear less enriched than the MZR median, while those with strong negative gradients are consistently more enriched in both simulated and observed samples. Interestingly, low-mass galaxies with strong negative ∇(O/H) exhibit high star-forming activity, regardless of stellar surface density or ∇(O/H). In contrast, a discrepancy arises for massive galaxies between MaNGA and EAGLE data sets. The latter exhibit a notable anticorrelation between specific star formation rate and stellar surface density, independent of ∇(O/H), while MaNGA galaxies show this trend mainly for strong positive ∇(O/H). Further investigation indicates that galaxies with strong negative gradients tend to host smaller central black holes in observed data sets, a trend not replicated in simulations. These findings suggest disparities in metallicity recycling and mixing history between observations and simulations, particularly in massive galaxies with varying metallicity gradients. These distinctions could contribute to a more comprehensive understanding of the underlying physics.
Dynamics of cold circumstellar gas in debris discs
Authors: Cui Can , Marino Sebastian , Kral Quentin , Latter Henrik 
Published: April 2024

ABSTRACT
Mounting observational evidence indicates that cold circumstellar gas is present in debris disc systems. This work focuses on various dynamical processes that debris disc gas may undergo. We review five mechanisms that can transport angular momentum and their applications to debris discs. These include molecular viscosity, hydrodynamic turbulence, magnetohydrodynamic (MHD) turbulence, magnetized disc winds, and laminar magnetic stress. We find that molecular viscosity can result in α as high as ≲0.1 for sufficiently low densities, while the Rossby wave instability is a possible source of hydrodynamic turbulence and structure formation. We argue that the vertical shear instability is unlikely due to the long cooling times. The onset of the magnetorotational instability (MRI) is dichotomous: for low-density discs the MRI can be excited at the mid-plane, while for high-mass discs it may only be operating at z &gt; 2 − 3H, if at all. The MHD wind and laminar magnetic stress mechanisms rely on the configuration and strength of any background large-scale magnetic field, the existence of which is uncertain and possibly unlikely. We conclude that the dominant mechanism and its efficiency in transporting angular momentum vary from one system to the other, depending especially closely on the gas density. More detailed analyses shall be performed in the future focusing on representative, nearby debris discs.
Changes in U.S. Adolescent Nicotine Vaping Prevalence From 2022 to 2023: The Role of Reduced Initiation Three Years Earlier During the Onset of the Pandemic
Authors: Miech Richard 
Published: April 2024

Abstract

Introduction
The prevalence of adolescent nicotine vaping declined substantially after the COVID-19 pandemic onset in the United States during the Spring of 2020. This study examines whether the decline continued from 2022 to 2023, and the extent to which any decline reflects the lasting influence of lowered levels of initiation 3 years earlier, at the onset of the pandemic.

Aims and Methods
Data for this study come from nationally representative, cross-sectional surveys of U.S. 12th-grade (n = 9854) and 10th-grade (n = 14 663) students administered in the Spring of 2022 and 2023. The main outcomes are past 12-month nicotine vaping and grade first ever vaped nicotine.

Results
From 2022 to 2023 prevalence of past 12-month nicotine vaping declined a relative 20% for 12th-grade students, from 24.3% to 19.1%, and for 10th-grade students by a relative 16%, from 17.8% to 15.1%. Among 12th-grade students who vaped nicotine in the past 12 months, a significant decline in prevalence took place only among those who first ever vaped nicotine in ninth grade, and not among those who first ever vaped nicotine in any other grade. Among 10th grade students who vaped nicotine in the past 12 months, a significant decline in prevalence took place only among those who first ever vaped nicotine in seventh grade, and not among those who first ever vaped nicotine in any other grade.

Conclusions
These results contribute national-level evidence that forestalled initiation of nicotine use for 1 year may have a lasting effect that continues to lower adolescents’ levels of use many years afterward.

Implications
These findings caution against looking to contemporaneous policy for explanations of the large, 1-year decline in nicotine vaping from 2022 to 2023. It can be tempting to interpret the decline as a victory for current efforts to restrict adolescent access to vaping products, or current education/media campaigns that warn adolescents of the dangers of vaping. The findings of this study suggest, instead, that the 1-year vaping declines primarily result from declines in initiation that were set into place 3 years ago during the pandemic onset, more so than the immediate result of contemporaneous policy.
Cohort Effects on Tobacco Consumption and Its Genetic and Environmental Variance Among Finnish Adults Born Between 1880 and 1957
Authors: Zellers Stephanie , Maes Hermine H M , Latvala Antti , Kaprio Jaakko 
Published: April 2024

Abstract

Introduction
Population research indicates that smoking behaviors in Finland have varied over time by sex and birth cohort. Smoking behaviors are influenced by genes and the environment; like the behaviors themselves, these underlying influences are not necessarily stable over time and may be modifiable by national drug policy.

Aims and Methods
We utilized longitudinal mixed-effects models and causal–common–contingent twin models to evaluate sex and cohort effects on tobacco consumption and the underlying genetic and environmental variance components in a birth cohort sample of same-sex twins born in Finland between 1880 and 1957, assessed in 1975, 1981, 1990, and 2011.

Results
We identified significant main effects of age, sex, and cohort on quantity of cigarette consumption, as well as significant age × cohort and sex × cohort interactions. We also identified sex and cohort effects on the liability to initiate regular smoking and the magnitude of variation underlying quantity of cigarette consumption. That said, heritability and environmental contributions to both traits were not different between the four sex × cohort groups.

Conclusions
Our results indicate sex and cohort effects on the prevalence of smoking and its underlying variation. Our results on changing prevalence mirror existing population-level research in Finnish samples, but we did not identify differences in heritability found in other studies of cohort effects in tobacco use, potentially due to power issues. These results highlight the importance of considering age, cohort, and timing of policy changes when evaluating changes in substance consumption across time.

Implications
This study identifies sex and cohort effects influencing tobacco consumption in a sample of Finnish adult twins born between 1880 and 1957. Our results are in line with other population-level research in Finland and research on cohort effects influencing alcohol use in the same sample. Our results highlight the intertwining effects of age, cohort, sex, and substance policies on substance use.
Are People More Likely to Vape or Smoke Indoors? A Population Survey of Adults in England
Authors: Tattan-Birch Harry , Jackson Sarah E , Shahab Lion , Brown Jamie 
Published: April 2024

Abstract

Background
Increasingly, people smoke cigarettes outdoors and avoid exposing bystanders to harm. People may not have the same motivation to vape outdoors since e-cigarettes, unlike cigarettes, do not create side stream emissions and exhaled aerosol contains fewer toxicants than secondhand smoke. This study aims to estimate the prevalence and correlates of vaping and smoking indoors among adults in England.

Aims and Methods
Data came from the Health Survey for England 2019, a cross-sectional household survey. Adults who vape or smoke (N = 1530) were asked whether they had vaped or smoked indoors inside the home, car, or other places within the past 7 days. Logistic regression was used to estimate prevalence and key correlates of indoor use, including age, sex, presence of adults/children in home, housing tenure, and nicotine dependence.

Results
People who exclusively vaped were much more likely to use their product indoors than those who exclusively smoked (87.0% vs. 52.0%; odds ratio [OR] = 6.16, 95% confidence interval [CI] = 4.09 to 9.28). Similarly, people who dual used had higher odds of vaping than smoking indoors (62.1% vs. 44.3%; OR = 3.76, 95% CI = 2.06 to 6.84). The preference for vaping over smoking indoors was found across different locations, including at home and in cars. Those who were older, highly dependent on nicotine, and lived alone were most prone to use any product indoors. While housing tenure was not strongly associated with vaping indoors, those living in social housing were much more likely to smoke indoors than homeowners.

Conclusions
Adults in England are much more likely to vape than smoke indoors. Age, nicotine dependence, and living alone are strongly associated with both behaviors.

Implications
Our results show that people have a strong preference for vaping over smoking indoors, including in the home. Given the high prevalence of vaping indoors, policy makers, landlords, and businesses must weigh up the ethics, benefits, and harms of extending smoke-free laws to include e-cigarettes.
Geochemical Evidence of Plume Sources for High-MgO Lavas in the Western Kunlun Orogenic Belt
Authors: Cheng Zhiguo , Zhang Zhaochong , Lang Mingde , Santosh M , Xu Lijuan , Liu Jingao 
Published: April 2024

Abstract
Plume-derived high-MgO lavas provide important information on the lithological, thermal and chemical variations of Earth’s deep mantle. Here we present results from detailed field, mineralogical and geochemical studies of Late Permian–Late Triassic high-MgO lavas near the Chalukou area in the Western Kunlun (WK) orogenic belt, NW China. The major element compositions of the lavas show extremely high MgO contents (26.6–33.8 wt %) in accordance with olivine accumulation. The parental magma is inferred to be picritic in composition with MgO of 17.2 ± 0.9 wt %. Olivine Zn/Fe and Mn/Zn ratios suggest a peridotite-dominated source with a minor fraction of pyroxenite. The temperature and oxygen fugacity estimates based on multi-methods including olivine-melt Mg–Fe equilibria, Al-in-olivine and olivine–spinel thermometry and oxybarometer yield a mantle potential temperature of 1522–1556 °C and high oxygen fugacity of FMQ (fayalite-magnetite-quartz) + 0.93. The H2O contents in the picrite flows are estimated as 3.67 ± 1.0 wt %, indicating the volatile-rich nature of parental magma and its mantle source. The immobile trace element features show that the WK picrites are OIB (oceanic island basalt)-like, with the enrichment in light rare earth elements and positive Nb, Ta, Zr and Hf anomalies. Furthermore, the Nd–O–Os isotopes display typical mantle values without involvement of recycled materials. Our results suggest the high-MgO volcanism in the WK orogenic belt originated from a volatile-rich plume source.
The Elusive Gains from Nationally Oriented Monetary Policy
Authors: Bodenstein Martin , Corsetti Giancarlo , Guerrieri Luca 
Published: April 2024

Abstract
The gains from monetary policy cooperation depend on real and financial distortions in the economy and evolve dynamically with prevailing economic conditions. We show that, with international trade in assets, these gains are driven by asymmetric cross-border developments in productivity and savings, and can reach multiples of the cost of economic fluctuations. When financial flows are restricted to nonstate-contingent bonds, the gains from cooperation grow with the size of global imbalances, i.e. net-foreign-asset positions.
The Use of Mobility-Focused Outcome Measures for Young Adults With Cancer Undergoing Chemotherapy
Authors: Edward Holly , Nayiga Brenda , Nicolau Daniel , Darsot Faheemah , Smith-Turchyn Jenna 
Published: April 2024

Background:Young adults living with cancer face many unique challenges during treatment and throughout survivorship. Chemotherapy is a standard anticancer treatment that has been known to lead to negative side effects on health including loss of muscle mass, strength, and physical function (ie, physical mobility). This scoping review aimed to explore what, how, and when mobility-focused outcome measures are being used during chemotherapy treatments for young adults living with cancer to examine changes in physical mobility.Methods:Five databases were searched. To be included in this review, studies must have included young adults (age 18-40) living with cancer, who were receiving chemotherapy treatment and used any form of physical mobility measurement during treatment. Duplicates were removed, and all screening and data extraction were performed by 2 or more independent reviewers.Results:A total of 1734 studies were screened, and four studies were included in this review. Three studies included a self-reported activity log. All studies assessed physical mobility using types of performance-based outcome measures such as accelerometers, muscle strength tests, cycle ergometer testing, or the 6- minute walk test. Assessments were conducted in person by study personnel in 2 studies. Outcomes were assessed throughout the chemotherapy cycle, including preadministration, over the first 7 days, weekly, and months into treatment.Conclusion:Although a scarcity of available literature exists, this review highlights the potential for screening and monitoring changes in mobility for young adults with cancer. Clinical application of the measures highlighted in this review shows promise in guiding appropriate interventions and informing changes in treatment dosage. Future research should build upon existing work to address the limited availability of mobility measures validated in this population.
Timely Completion of Direct Access Colonoscopy Is Noninferior to Office Scheduled for Screening and Surveillance
Authors: White Mary , Israilevich Rachel , Lam Sophia , McCarthy Michael , Mico Vasil , Chipkin Benjamin , Abrams Eric , Moore Kelly , Kastenberg David 
Published: April 2024

Goals:
We aimed to evaluate whether direct access colonoscopy (DAC) is noninferior to office-scheduled colonoscopy (OSC) for achieving successful colonoscopy.

Background:
DAC may improve access to colonoscopy. We developed an algorithm assessing eligibility, risk for inadequate preparation, and need for nursing/navigator assistance.

Study:
This was a retrospective, single-center study of DAC and OSC patients from June 5, 2018, to July 31, 2019. Patients were 45 to 75 years old with an indication of screening or surveillance. A successful colonoscopy met 3 criteria: complete colonoscopy (cecum, anastomosis, or ileum), adequate preparation (Boston Score ≥2/segment), and performed <90 days from initial patient contact. Unsuccessful colonoscopy did not meet ≥1 criteria. Secondary end points included days to successful colonoscopy, preparation quality, polyp detection, and 10-year recall rate. Noninferiority against risk ratio value of 0.85 was tested using 1-sided alpha of 0.05.

Results:
A total of 1823 DAC and 828 OSC patients were eligible. DAC patients were younger, with a greater proportion of black patients and screening indications. For the outcome of successful colonoscopy, DAC was noninferior to OSC (DAC vs. OSC: 62.7% vs. 57.1%, RR 1.16, 95% LCL 1.09, P=0.001). For DAC, days to colonoscopy were fewer, and likelihood of 10-year recall after negative screening greater. Boston Score and polyp detection were similar for groups. Black patients were less likely to achieve successful colonoscopy; otherwise, groups were similar. For unsuccessful colonoscopies, proportionally more DAC patients canceled or no-showed while more OSC patients scheduled >90 days. DAC remained noninferior to OSC at 180 days.

Conclusions:
DAC was noninferior to OSC for achieving successful colonoscopy, comparing similarly in quality and efficiency outcomes.
Protocol for a Randomized Controlled Trial to Evaluate a Permissive Blood Pressure Target Versus Usual Care in Critically Ill Children with Hypotension (PRESSURE)
Authors: Darnell Robert , Brown Alanna , Laing Emma , Edwards Julia , Harrison David A. , Manning Joseph C. , Peters Mark J. , Ramnarayan Padmanabhan , Ray Samiran , Sadique Zia , Scholefield Barnaby R. , Shortt Dermot , Lampro Lamprini , Au Carly , Rowan Kathy M. , Mouncey Paul , Inwald David P. ,   Protocolised Evaluation of Permissive Blood Pressure Targets Versus Usual Care (PRESSURE) Trial Investigators on behalf of the U.K. Paediatric Critical Care Society Study Group (PCCS-SG)
Published: April 2024

OBJECTIVES:Management of hypotension is a fundamental part of pediatric critical care, with cardiovascular support in the form of fluids or vasoactive drugs offered to every hypotensive child. However, optimal blood pressure (BP) targets are unknown. The PRotocolised Evaluation of PermiSSive BP Targets Versus Usual CaRE (PRESSURE) trial aims to evaluate the clinical and cost-effectiveness of a permissive mean arterial pressure (MAP) target of greater than a fifth centile for age compared with usual care.DESIGN:Pragmatic, open, multicenter, parallel-group randomized control trial (RCT) with integrated economic evaluation.SETTING:Eighteen PICUs across the United Kingdom.PATIENTS:Infants and children older than 37 weeks corrected gestational age to 16 years accepted to a participating PICU, on mechanical ventilation and receiving vasoactive drugs for hypotension.INTERVENTIONS:Adjustment of hemodynamic support to achieve a permissive MAP target greater than fifth centile for age during invasive mechanical ventilation.MEASUREMENTS AND MAIN RESULTS:Randomization is 1:1 to a permissive MAP target or usual care, stratified by site and age group. Due to the emergency nature of the treatment, approaching patients for written informed consent will be deferred until after randomization. The primary clinical outcome is a composite of death and days of ventilatory support at 30 days. Baseline demographics and clinical status will be recorded as well as daily measures of BP and organ support, and discharge outcomes. This RCT received Health Research Authority approval (reference 289545), and a favorable ethical opinion from the East of England—Cambridge South Research Ethics Committee on May 10, 2021 (reference number 21/EE/0084). The trial is registered and has an International Standard RCT Number (reference 20609635).CONCLUSIONS:Trial findings will be disseminated in U.K. national and international conferences and in peer-reviewed journals.