Aerosol Thermodynamics: Nitrate Loss from Regulatory PM2.5 Filters in California.

Fine particulate matter (PM2.5) mass concentrations reported by regulatory networks are declining across the United States. It is well established that ammonium nitrate contributes substantially to the PM2.5 mass in the western United States, and that Teflon filters commonly used by regulatory monitors are subject to negative mass artifacts due to ammonium nitrate volatilization. This study focuses on the San Joaquin Valley (SJV), an environmental justice (EJ) and agricultural region with persistently poor air quality. The SJV is a serious nonattainment area of PM2.5 National Ambient Air Quality Standards (NAAQS) with substantial nitrate mass concentrations. We explicitly model the chemical thermodynamic equilibrium of the ammonium nitrate-nitric acid systems and quantify volatilization across California as a function of the deliquescence point relative humidity (%DRH). Nitrate loss is estimated at all federal reference method (FRM) and federal equivalent method (FEM) monitors from 2001 to 2021. Nearly 20% of PM2.5 mass is lost from filters in the SJV area, especially during winter and fall when particulate nitrate mass is most abundant. All decadal PM2.5 trends calculated from reported measurements in Kern, Tulare, and Fresno counties in the SJV show greater decline in PM2.5 mass when nitrate loss is accounted for, up to a factor of 20 in Kern county. This suggests PM2.5 mass concentrations reported in regulatory networks are biased low relative to the actual atmospheric burden, notably in an EJ area that lags behind most of the country's air quality improvements.

A new method for evaluating radial neck fractures based on Judet classification.

Aims: To propose a new method for evaluating paediatric radial neck fractures and improve the accuracy of fracture angulation measurement, particularly in younger children, and thereby facilitate planning treatment in this population. Methods: Clinical data of 117 children with radial neck fractures in our hospital from August 2014 to March 2023 were collected. A total of 50 children (26 males, 24 females, mean age 7.6 years (2 to 13)) met the inclusion criteria and were analyzed. Cases were excluded for the following reasons: Judet grade I and Judet grade IVb (> 85° angulation) classification; poor radiograph image quality; incomplete clinical information; sagittal plane angulation; severe displacement of the ulna fracture; and Monteggia fractures. For each patient, standard elbow anteroposterior (AP) view radiographs and corresponding CT images were acquired. On radiographs, Angle P (complementary to the angle between the long axis of the radial head and the line perpendicular to the physis), Angle S (complementary to the angle between the long axis of the radial head and the midline through the proximal radial shaft), and Angle U (between the long axis of the radial head and the straight line from the distal tip of the capitellum to the coronoid process) were identified as candidates approximating the true coronal plane angulation of radial neck fractures. On the coronal plane of the CT scan, the angulation of radial neck fractures (CTa) was measured and served as the reference standard for measurement. Inter- and intraobserver reliabilities were assessed by Kappa statistics and intraclass correlation coefficient (ICC). Results: Angle U showed the strongest correlation with CTa (p < 0.001). In the analysis of inter- and intraobserver reliability, Kappa values were significantly higher for Angles S and U compared with Angle P. ICC values were excellent among the three groups. Conclusion: Angle U on AP view was the best substitute for CTa when evaluating radial neck fractures in children. Further studies are required to validate this method.

Mediating Effect of the NLR on the Relationship Between HbA1c and Left Atrial Stiffness in Overweight Patients With Hypertension.

BACKGROUND: We aimed to investigate the association between hemoglobin A1c (HbA1c) and left atrial (LA) stiffness in patients with hypertension and to explore the mediating effect of the neutrophil/lymphocyte ratio (NLR) on this association. METHODS: Essential hypertensive patients (n = 292) aged 18-83 years were enrolled and divided into two groups based on the LA stiffness index (LASI): Group I (LASI ≤ 0.32, n = 146) and Group II (LASI > 0.32, n = 146). The LASI was defined as the ratio of early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') to LA reservoir strain. Multivariate linear regression analysis was performed to determine the independent predictors of the LASI. RESULTS: Age, BMI, SBP, HbA1c, CRP, and NLR were significantly greater in Group II than in Group I (P < 0.05). Additionally, Group II had a greater LA volume index (LAVI), left ventricular mass index (LVMI), and early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') and lower LA reservoir, conduit, and booster pump strains than Group I (P < 0.001). Univariate and multivariate linear regression models revealed that age, SBP, HbA1c, and the NLR were independently associated with the LASI. Further mediation analysis was performed to determine the mediating effect of the NLR on the association between HbA1c and the LASI and revealed that the NLR had a mediating role only in overweight hypertensive patients, and the proportion of the mediating effect was 21.9%. CONCLUSIONS: The NLR was independently correlated with the LASI and played a mediating role in the relationship between HbA1c and the LASI in overweight hypertensive patients.

Taking Our Pulse: Examining 5 Years of Data from the Association of Pediatric Program Directors Research and Scholarship Learning Community.

BACKGROUND: The Association of Pediatric Program Directors Research and Scholarship Learning Community (RSLC) prioritizes and comprehensively reviews medical education surveys directed to residency program leadership. Each survey is reviewed by two members of RSLC and the Chair and Vice Chair using a standardized scoring rubric and a limited number of surveys are accepted per cycle. METHODS: Internal review data from 2015 to 2020 were analyzed to determine factors associated with survey acceptance, and for surveys accepted for distribution, determine factors associated with response rates or dissemination status. One-Way analysis of variance (ANOVA) assessed differences in evaluation scores by initial determination status. T-tests and Pearson Product Correlation assessed associations between evaluation scores and response rates by dissemination status. RESULTS: The majority (47/81; 58%) of surveys submitted to RSLC are eventually accepted for distribution. Response rates for distributed surveys varied between 14% and 73%. Most (35/47; 74%) surveys distributed through RSLC are presented (62%) and/or published (60%). Higher review scores were associated with acceptance for distribution but not with response rates or dissemination status. CONCLUSION: Most surveys are eventually accepted by RSLC for distribution and those distributed often get published or presented despite variability in response rates.

Getting the Most Out of Your Medical Education Survey: 11 Tips From the Association of Pediatric Program Directors Research and Scholarship Learning Community.

OBJECTIVE: Surveys in medical education are commonplace. However, survey studies often lack scientific rigor. Well-designed surveys can ensure improved response rates and higher likelihood of dissemination. The purpose of this paper is to provide guidance for investigators planning to survey pediatric residency leaders METHODS: We examined the Association of Pediatric Program Directors Research and Scholarship Learning Community (APPD-RSLC) submissions, acceptances, and outcomes between 2015 and 2020. Additionally, we performed a literature review of survey design methods with the help of a research librarian. We established a list of tips and settled on the 11 included here by group discussion and consensus. CONCLUSION: These 11 tips provide specific recommendations for successful design of medical education surveys distributed by the APPD based on experience from current and former leaders of the RSLC and literature review in survey design and implementation.

Off the Shelf Multibranched Endograft for Thoraco-Abdominal and Pararenal Abdominal Aortic Aneurysms: a Prospective, Single Centre Study of the G-Branch Endograft.

OBJECTIVE: To investigate outcomes of a novel, off the shelf multibranched endovascular stent graft for the treatment of thoraco-abdominal aortic aneurysm (TAAA) and pararenal abdominal aortic aneurysm (PAAA). METHODS: A prospective, single centre study including 15 patients (mean age, 63.4 ± 10.7 years; 13 male) with TAAA or PAAA treated from October 2019 to March 2021 with a G-Branch endograft (Lifetech Scientific, Shenzhen, China) featuring a mixed multibranch design with two inner and two outer branches for reconstruction of the visceral and bilateral renal arteries, respectively. Follow up assessments were scheduled before discharge and at 30 days, six and 12 months after the index procedure. Annual telephone interviews were performed beyond the initial 12 months. The Kaplan-Meier method was used to estimate cumulative mortality and morbidity rates after endovascular repair. RESULTS: Technical success was achieved in all 15 patients. Nine patients (60%) had TAAA and six (40%) had PAAA (mean maximum aneurysm diameter, 73.7 ± 15.8 mm). The median follow up was 31.4 months (range, 10.1 - 44.0 months). At 30 days, there was no death and 7% morbidity (one case of temporary spinal cord ischaemia on Day 4). At one year, the mortality rate was 7% (one death from stroke at 10 months) and morbidity was 13% (one other case of renal function decline at six months). There were no aneurysm dilatations, re-interventions, or access related complications, and two (13%) persistent type II endoleaks. The one year primary branch patency rate was 100% for the four renovisceral arteries in all 13 patients who underwent computed tomography examinations. One patient died of hepatocellular carcinoma 29 months post-operatively, resulting in an estimated three year mortality rate of 13%. CONCLUSION: The G-Branch endograft yielded high technical success with good early and midterm outcomes for the treatment of TAAA and PAAA. A large multicentre study is warranted.

A scoping review of social media in child, adolescents and young adults: research findings in depression, anxiety and other clinical challenges.

BACKGROUND: Social media and other technologies are reshaping communication and health. AIMS: This review addresses the relationship between social media use, behavioural health conditions and psychological well-being for youth aged <25 years. METHOD: A scoping review of 11 literature databases from 2000 to 2020 explored research studies in youth in five areas: clinical depression and anxiety, quantitative use, social media mode, engagement and qualitative dimensions and health and well-being. RESULTS: Out of 2820 potential literature references, 140 met the inclusion criteria. The foci were clinical depression and anxiety disorders (n = 78), clinical challenges (e.g. suicidal ideation, cyberbullying) (n = 34) and psychological well-being (n = 28). Most studies focused on Facebook, Twitter, Instagram and YouTube. Few studies are longitudinal in design (n = 26), had comparison groups (n = 27), were randomised controlled trials (n = 3) or used structured assessments (n = 4). Few focused on different youth and sociodemographic populations, particularly for low-income, equity-seeking and deserving populations. Studies examined association (n = 120; 85.7%), mediating (n = 16; 11.4%) and causal (n = 4; 2.9%) relationships. Prospective, longitudinal studies of depression and anxiety appear to indicate that shorter use (≤3 h/day) and purposeful engagement is associated with better mood and psychological well-being. Depression may predict social media use and reduce perception of support. Findings provide families, teachers and providers ways to engage youth. CONCLUSIONS: Research opportunities include clinical outcomes from functional perspective on a health continuum, diverse youth and sociodemographic populations, methodology, intervention and privacy issues. More longitudinal studies, comparison designs and effectiveness approaches are also needed. Health systems face clinical, training and professional development challenges.

Harnessing Aromatic-Histidine Interactions through Synergistic Backbone Extension and Side Chain Modification.

Peptide engineering efforts have delivered drugs for diverse human diseases. Side chain alteration is among the most common approaches to designing new peptides for specific applications. The peptide backbone can be modified as well, but this strategy has received relatively little attention. Here we show that new and favorable contacts between a His side chain on a target protein and an aromatic side chain on a synthetic peptide ligand can be engineered by rational and coordinated side chain modification and backbone extension. Side chain modification alone was unsuccessful. Binding measurements, high-resolution structural studies and pharmacological outcomes all support the synergy between backbone and side chain modification in engineered ligands of the parathyroid hormone receptor-1, which is targeted by osteoporosis drugs. These results should motivate other structure-based designs featuring coordinated side chain modification and backbone extension to enhance the engagement of peptide ligands with target proteins.

Are Final Residency Milestones Correlated With Early Fellowship Performance in Pediatrics?

PURPOSE: Milestones have been used to assess trainees across graduate medical education programs and reflect a developmental continuum from novice to expert. This study examined whether residency milestones are correlated with initial fellowship milestone performance in pediatrics. METHOD: This retrospective cohort study used descriptive statistics to assess milestone scores from pediatric fellows who began fellowship training between July 2017 and July 2020. Milestone scores were obtained at the end of residency (R), middle of the first fellowship year (F1), and end of the first fellowship year (F2). RESULTS: Data represent 3,592 unique trainees. High composite R scores, much lower F1 scores, and slightly higher F2 scores were found over time for all pediatric subspecialities. R scores were positively correlated with F1 scores (Spearman ρ = 0.12, P < .001) and F2 scores (Spearman ρ = 0.15, P < .001). Although scores are negligibly different when trainees graduate from residency, there were differences in F1 and F2 scores among fellows in different specialties. Those who trained at the same institution for residency and fellowship had higher composite milestone F1 and F2 scores compared with those who trained at different institutions ( P < .001). The strongest associations were between R and F2 scores for the professionalism and communication milestones, although associations were still relatively weak overall (r s = 0.13-0.20). CONCLUSIONS: This study found high R scores and low F1 and F2 scores across all shared milestones, with weak association of scores within competencies, indicating that milestones are context dependent. Although professionalism and communication milestones had a higher correlation compared with the other competencies, the association was still weak. Residency milestones may be useful for individualized education in early fellowship, but fellowship programs should be cautious about overreliance on R scores due to the weak correlation with F1 and F2 scores.

RMechDB: A Public Database of Elementary Radical Reaction Steps.

We introduce RMechDB, an open-access platform for aggregating, curating, and distributing reliable data about elementary radical reaction steps for computational radical reaction modeling and prediction. RMechDB contains over 5,300 elementary radical reaction steps, each with a single transition state at or around room temperature. These elementary step reactions are manually curated plausible arrow-pushing steps for organic radical reactions. The steps were taken from a variety of sources. Over 2,000 mechanistic steps were extracted from textbooks and/or constructed from research publications. Another 3,000 were taken from gas-phase atmospheric reactions of isoprene and other organic molecules on the MCM (Master Chemical Mechanism) Web site. Reactions are encoded in the SMIRKS format with accurate atom mapping and annotations for arrow-pushing mechanisms. At its core, RMechDB consists of a database schema with an online interactive search interface and a request portal for downloading the raw form of elementary step reactions with their metadata. It also offers an interface for submitting new reactions to RMechDB and expanding the data set through community contributions. Although there are several applications for RMechDB, it is primarily designed as a central platform of radical elementary steps with a unified and structured representation. We believe that this open access to this data and platform enables the extension of data-driven models for chemical reaction predictions and other chemoinformatics predictive tasks.

Composite Proton-Conducting Membrane with Enhanced Phosphoric Acid Doping of Basic Films Radiochemically Grafted with Binary Vinyl Heterocyclic Monomer Mixtures.

A composite proton conducting membrane (PCM) was prepared by radiation-induced grafting (RIG) of binary mixtures of 4-vinyl pyridine (4-VP) and 1-vinylimidazole (1-VIm) onto poly(ethylene-co-tetrafluoroethylene) (ETFE) film followed by phosphoric acid (PA) doping. The grafting parameters such as absorbed dose, temperature, monomer concentration, time, and monomer ratio were varied to control the degree of grafting (DG%). The effect of the reactivity ratio of 4-VP and 1-VIm on the composition and degree of monomer unit alternation in the formed graft copolymer was investigated. The changes in the chemical and physical properties endowed by grafting and subsequent PA acid doping were monitored using analytical instruments. The mechanical properties and proton conductivity of the obtained membrane were evaluated and its performance was tested in H2/O2 fuel cell at 120 °C under anhydrous and partially wet conditions. The acid doping level was affected by the treatment parameters and enhanced by increasing DG. The proton conductivity was boosted by incorporating the combination of pyridine and imidazole rings originating from the formed basic graft copolymer of 4-VP/1-VIm dominated by 4-VP units in the structure. The proton conductivity showed a strong dependence on the temperature. The membrane demonstrated superior properties compared to its counterpart obtained by grafting 4-VP alone. The membrane also showed a strong potential for application in proton exchange membrane fuel cells (PEMFC) operating at 120 °C.

Differential Effects of Work and Family Support on the Relationship Between Surface Acting and Wellbeing: A Self-Determination Theory Approach.

Surface acting-the management of emotional displays as part of a nurse's work role-is increasingly getting scholars' attention in organizational behavior. Previous research focused on the relationship between surface acting and outcomes (such as psychological well-being) on the basis of resource-centric theories, ignoring the subjective stance of surface acting provider. According to self-determination theory, surface acting affects an individual's well-being through stimulating autonomous or controlled work motivation. Taking nurses as the subjects, the current study proposed that surface acting would affect job satisfaction and further psychological well-being through nurses' controlled work motivation, and work and family support would moderate the above relationships in diverse directions. An online survey of n = 342 nurses working at a hospital in central China was conducted, evaluating surface acting, job satisfaction, psychological well-being, workplace support, and family support. Results indicated that surface acting negatively influenced nurses' psychological well-being through job satisfaction. In addition, the results highlighted the two-faced aspect of social support, in which work support positively moderated the relationships between surface acting, job satisfaction, and psychological well-being, while family support intensified the abovementioned relationships negatively. These findings have important implications for surface acting, social support research, and managerial practices.

Enhancing Learner Engagement Through Experiential Learning With Learner-Generated Data.

Integrating self-generated learner data into hands-on curricula enhances learner engagement with material and self-assessed learning. Using learner self-generated data to enhance learner engagement can have widespread applicability and benefit for use in design of educational curricula.

The Early Effects of the Coronavirus Disease-19 Pandemic on Pediatric Resident Education: A National Assessment.

PURPOSE: Residency programs must ensure resident competence for independent practice. The coronavirus disease-19 (COVID-19) pandemic disrupted health care delivery, impacting pediatric residencies. This study examines the impact on pediatric resident education. METHODS: The authors conducted a mixed methods national survey of pediatric residency program directors (PDs) from May 2020 to July 2020. Data analysis included descriptive statistics, chi-square, and Wilcoxon rank sum tests. Multivariable modeling identified factors associated with resident preparation for more senior roles. Thematic analysis was performed on open-ended questions about PD COVID-19 pandemic recommendations to peers, Accreditation Council for Graduate Medical Education and American Board of Pediatrics. RESULTS: Response rate was 55% (110/199). PDs reported the COVID-19 pandemic negatively affected inpatient (n = 86, 78.2%), and outpatient education (n = 104, 94.5%), procedural competence (n = 64; 58.2%), and resident preparation for more senior roles (n = 50, 45.5%). In bivariate analyses, increasingly negative impacts on inpatient and outpatient education were associated with an increasingly negative impact on resident preparation for more senior roles (P = .03, P = .008), these relationships held true in multivariable analysis. Qualitative analysis identified 4 themes from PD recommendations: 1) Clear communication from governing bodies and other leaders; 2) Flexibility within programs and from governing bodies; 3) Clinical exposure is key for competency development; 4) Online platforms are important for education, communication, and support. CONCLUSIONS: The COVID-19 pandemic negatively impacted inpatient and outpatient education. When these were more negatively impacted, resident preparation for more senior roles was worse, highlighting the importance of competency based medical education to tailor experiences ensuring each resident is competent for independent practice.

COVID-19 Pandemic Impact on Pediatricians Entering the Pediatric Workforce.

OBJECTIVE: Determine extent of impact of coronavirus disease 2019 (COVID-19) pandemic on career choice and employment of pediatricians entering pediatric workforce. METHODS: A national, cross-sectional electronic survey of pediatricians registering for the 2021 American Board of Pediatrics initial general certifying examination on the impact of the COVID-19 pandemic on 3 aspects of career (career choice, employment search, employment offers) was performed. Data were analyzed using descriptive statistics and multivariate logistic regression to determine factors associated with the pandemic's impact on career. Thematic analysis was used to generate themes for open-ended survey questions. RESULTS: Over half (52.3%, 1767 of 3380) of pediatricians responded. Overall, 29.1% reported that the pandemic impacted their career (career choice [10.4%], employment search [15.6%], or employment offers [19.0%]); applicants to general pediatrics (GP) (52.9%) or pediatric hospitalist (PH) positions (49.3%) were most affected. Multivariate logistic regression modeling found those applying to GP (odds ratio [OR]: 3.83, 95% confidence interval [CI]: 2.22-6.60), PH (OR: 9.02, 95% CI: 5.60-14.52), and International Medical Graduates (IMGs) (OR: 1.90; 95% CI: 1.39-2.59) most likely to experience any career impact. CONCLUSIONS: Almost one third of pediatricians registering for the initial general pediatrics certifying examination reported their careers were impacted by the COVID-19 pandemic, with 10% of respondents reporting the pandemic impacted their career choice. Half of new pediatricians seeking employment reported being impacted by the pandemic, particularly IMGs. As the pandemic evolves, career advising will continue to be critical to support trainees in their career choices and employment.