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Physicians have gravitated toward larger group practice arrangements in recent years. However, consolidation trends in colorectal surgery have yet to be well described. Our objective was to assess current trends in practice consolidation within colorectal surgery and evaluate underlying demographic trends including age, gender, and geography. We performed a retrospective cross-sectional study using the Center for Medicare Services National Downloadable File from 2015 to 2022. Colorectal surgeons were categorized by practice size and by region, gender, and age. From 2015 to 2022, the number of colorectal surgeons in the United States increased from 1369 to 1621 (+18.4%), while the practices with which they were affiliated remained relatively stable (693-721, +4.0%). The proportion of colorectal surgeons in groups of 1-2 members fell from 18.9% to 10.7%. Conversely, those in groups of 500+ members grew from 26.5% to 45.2% (linear trend P < 0.001). The midwest region demonstrated the highest degree of consolidation. Affiliations with group practices of 500+ members saw large increases from both female and male surgeons (+148.9% and +86.9%, respectively). New surgeons joining the field since 2015 overwhelmingly practice in larger groups (5.3% in groups of 1-2, 50.1% in groups of 500+). Colorectal surgeons are shifting toward larger practice affiliations. Although this change is happening across all demographic groups, it appears unevenly distributed across geography, gender, and age. New surgeons are preferentially joining large group practices. [ABSTRACT FROM AUTHOR]

The article focuses on catastrophic sports injuries in high school and college athletes, differentiating between traumatic and nontraumatic incidents. Topics discussed include the incidence trends over the past 40 years, specific sports associated with these injuries especially football, cheerleading, and basketball, and preventive measures, such as rule changes and targeted screenings for conditions like sickle cell trait and cardiac abnormalities.

The selective oxidation of n -butane to maleic anhydride is a strongly exothermic reaction. Resulting local hot-spots and intraparticle temperatures high above the surrounding fluid temperature are challenging for safe and economic operation of reactors. Detailed modelling on all length scales is therefore required for an accurate description of this process. In this contribution, the one dimensional description of the ring-shaped catalyst, commonly used in continuum reactor modelling, is compared to three dimensional computational fluid dynamics simulations for the case of a single catalyst particle at different inclination angles (0 to 90°). Polytropic chemical reaction is considered under typical n -butane oxidation conditions (R e p = 400), representing a catalyst particle close to the inlet, (T = 673 K) and at the hot-spot (T = 730 K) of an industrial reactor. Comparative analysis suggests that the one dimensional simplification is justified when external transport phenomena are not the limiting resistance. Otherwise, neglecting two spatial dimensions leads to erroneous predictions. [Display omitted] • Comparing single particle CFD & continuum model simulations for n -butane oxidation • Continuum model representation can lead to erroneous intraparticle profiles • Description of surface conditions decisive under external transport limitation [ABSTRACT FROM AUTHOR]

Background: Cutaneous lupus erythematosus (CLE) can present later in life, but frequency and risk factors of late-onset CLE patients are not well characterized. The study determined frequency of late-onset CLE and compared the demographic and disease characteristics between early-onset and late-onset CLE in a cohort of patients with CLE. Objectives: To determine the frequency and compare clinical features of early-onset and late-onset CLE. Methods: This was a cross-sectional study of CLE patients seen in outpatient dermatology clinics at University of Texas Southwestern Medical Center (UTSW) and Parkland Health and Hospital System, Dallas, TX, from April 2009 to May 2019. The primary outcome was the age of CLE onset, stratified by early-onset (<50 years) and late-onset CLE (≥50 years). Predictor variables significantly associated with CLE onset groups were identified by univariate and multivariable logistic regression analyses. Results: Of the 291 CLE patients studied, 79% were early-onset, and 21% were late-onset. Multivariable logistic regression analyses identified that Caucasian race (odds ratio (OR): 2.23, 95% Confidence Interval (CI): 1.19–4.19, p = 0.013), having a CLE subtype other than chronic (OR: 2.18, 95% CI: 1.02–4.65, p = 0.044), and drug-induced cases (OR: 4.65, 95% CI: 1.18–18.24, p = 0.028) were significantly associated with late-onset CLE. Early-onset CLE patients were more likely to have oral ulcers (OR: 3.58, 95% CI: 1.46–8.78, p = 0.005) and renal disorders (OR: 4.02, 95% CI: 1.10–14.71, p = 0.036). Limitations: This was a single center study. Age of onset was self-reported and late-onset CLE cohort has a small sample size. Conclusions: Our diverse cohort of CLE patients had about one out of five patients with CLE experiencing disease onset after 50 years old. These patients have distinct demographic and clinical presentations compared to early-onset CLE patients. Providers should remain mindful of CLE in older patients with photosensitive rashes and mild systemic symptoms. [ABSTRACT FROM AUTHOR]

This analysis of Barack Obama's "Address on the 50th Anniversary of the Selma, Alabama March" argues that the president used the African oral element of nommo to locate the civil rights protest within a broader narrative of American exceptionalism. In two stages, Obama first appealed to American exceptionalism to reconceptualize the impediments to Black citizenship at the time of the protest and then utilized counterargument to manage the tension between inclusion and exclusion underscoring the contemporary struggle for African Americans. While Obama's deployment of American exceptionalism functioned as an attempt to create a transformative perspective for the nation's pursuit of equality, the myth's colonialist foundation created space to decenter the Black cultural perspective from the debate over structural racism. Supplemental data for this article is available online at https://doi.org/10.1080/10646175.2021.1929580. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the relationship between acute, chronic, and acute:chronic sleep on aerobic performance in female youth soccer athletes. Fifty-nine female soccer players (13–18 years) reported prior night (acute) and average prior month (chronic) sleep duration before undergoing cycle ergometer testing to determine maximal aerobic capacity (VO2max), time to exhaustion (Tmax), and ventilatory threshold (VO2VT). Variables were grouped by prior night and prior month sleep duration (< 8 h, ≥ 8 h) as well as acute:chronic sleep (< 1, ≥ 1) and compared between groups using least squares means from age-adjusted linear models. No statistically significant differences were identified between those participants who slept ≥ 8 h the prior night and those who slept < 8 h, with respect to VO2max (50.3 ± 5.9 vs. 47.6 ± 5.9 ml/kg/min, p = 0.10, d = 0.45), Tmax (15.7 ± 2.8 vs.14.9 ± 2.2 min, p = 0.17, d = 0.37), or VO2VT (43.2 ± 5.4 vs. 40.7 ± 5.4 ml/kg/min, p = 0.09, d = 0.46). Participants who averaged ≥ 8 h of sleep in the prior month demonstrated significantly greater VO2max (50.2 ± 5.7 vs. 45.4 ± 5.7 ml/kg/min, p = 0.023, d = 0.83) and VO2VT (43.0 ± 5.2 vs. 39.0 ± 5.2 ml/kg/min, p = 0.016, d = 0.78), but not Tmax (15.6 ± 2.2 vs. 14.8 ± 2.2 min, p = 0.24, d = 0.37). On the other hand, participants with higher acute:chronic sleep demonstrated greater Tmax (16.4 ± 2.1 vs. 14.9 ± 2.1 min, p = 0.012, d = − 0.73), but not VO2max (50.1 ± 6.0 vs. 48.7 ± 6.0 ml/kg/min, p = 0.38, d = − 0.25) or VO2VT (42.7 ± 5.5 vs. 41.9 ± 5.5 ml/kg/min, p = 0.60, d = − 0.15). Greater chronic prior month sleep duration is associated with increased VO2max and VO2VT, while increased acute prior night sleep relative to the preceding month was associated with increased Tmax. [ABSTRACT FROM AUTHOR]

Congenital kidney failure not only affects the homeostatic functions of the kidney, but also affects neonatal respiratory integrity. Until recently, extracorporeal membrane oxygenation (ECMO) support was not used in this population because the need for ECMO clearly established nonviability. Since 2016, 31 neonates have been admitted to the NICU at Children's of Alabama with congenital kidney failure. Five patients were placed on ECMO for severe respiratory distress unresponsive to conventional interventions. We evaluated neonates with congenital kidney failure and pulmonary hypoplasia/hypertension refractory to conventional therapies who received ECMO support within the first 9 postnatal days. We describe the pre and postnatal diagnoses, ECMO course details, dialysis modalities, complications, procedures, and long-term outcomes of these patients. All 5 patients received kidney support therapy by postnatal day 7. Diagnoses included posterior urethral valves, bilateral renal dysplasia, and autosomal recessive polycystic kidney disease. Gestational age ranged from 35.6 to 37.1 weeks. Birth weight ranged from 2740 to 3140 g. Days on ECMO ranged from 4 to 23. Four survived and are living today. Pulmonary hypertension resolved in surviving patients. Three surviving patients require no oxygen support, and 1 patient requires nocturnal oxygen. Three survivors received a kidney transplant, and 1 awaits transplant evaluation. Patients with congenital kidney failure with severe pulmonary hypoplasia/pulmonary hypertension no longer warrant a reflexive assignment of nonviability. Meticulous ECMO, respiratory, nutritional, and kidney support therapies may achieve a favorable long-term outcome. Further investigation of strategies for optimal outcome is needed. [ABSTRACT FROM AUTHOR]

To quantify trends in ophthalmology practice consolidation in the United States. A retrospective cross-sectional study. Providers in the Centers for Medicare and Medicaid Services (CMS) National Downloadable File with a primary specialty designation of ophthalmology. We used the CMS database to determine national practice consolidation trends in ophthalmology on individual physician and group practice levels and analyzed by region, sex, and years spent in practice. We used the Cochran-Armitage test to determine the statistical significance of practice size differences between 2015 and 2022. Temporal practice size trends for physicians and practices in ophthalmology and regional, sex-specific, and age-related trends. Between 2015 and 2022, the number of ophthalmologists decreased from 17 656 to 17 615 (–0.2%), whereas the number of practices decreased from 7149 to 5890 (–18%). The percentage of ophthalmologists in practices of 1 to 2 members decreased from 35% to 28%, whereas those in groups of 50 or more increased from 7% to 11%. The percentage of practices with 1 to 2 members decreased from 75% to 71%, and those with 50 or more increased from 0.2% to 0.4%. Consolidation trends were significant on individual ophthalmologist (P < 0.001) and group practice (P < 0.001) levels. All regions, sexes, and subgroups of years spent in practice demonstrated consolidation (P < 0.001). The Northeast showed the greatest increase in groups of 50 or more physicians (+7%) between 2015 and 2022. Proportionally fewer female than male ophthalmologists were associated with practice sizes of 1 to 2 members in 2015 (29% and 36%, respectively) and 2022 (23% and 30%, respectively). Proportionally fewer ophthalmologists with 0 to 10 years of experience in practice were associated with practice sizes of 1 to 2 members than those with more than 30 years in practice in 2015 (18% and 48%, respectively) and 2022 (14% and 40%, respectively). Ophthalmology has undergone practice consolidation from 2015 to 2022. A decrease in the proportion of physicians affiliated with smaller practice sizes seems to have occurred. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. [ABSTRACT FROM AUTHOR]

Absolute kinetics for reactions of C2H2 with a series of ∼60 individual carbon nanoparticles (NPs) from graphite, graphene, graphene oxide, carbon black, diamond, and nano-onion feedstocks were measured for temperatures (TNP) ranging from 1200 to 1700 K. All the NPs were observed to gain mass by carbon addition under conditions that varied with feedstock but with large variations in initial growth rate. Long reaction periods were studied to allow the evolution of growth rates over time to be observed. Diamond NPs were found to passivate against C2H2 addition if heated above ∼1400 K, and the highly variable initial reactivity for carbon nano-onions was found to depend on the presence of non-onion-structure surface carbon. For graphitic and carbon black NPs, three distinct growth modes were observed, correlated with the initial NP mass (Minitial). Smallest graphitic and carbon black NPs, with masses <∼25 MDa, initially grew rapidly but also passivated quickly after adding <4% of Minitial. NPs in the 20–50 MDa range also passivated but only after multiple waves of fast growth separated by periods of low reactivity, with up to ∼11% total mass gain before passivation. The largest carbon black and graphitic NPs, with Minitial >50 MDa, grew rapidly and continuously, adding up to ∼300% of Minitial with no sign of rate slowing as long as C2H2 was present. The efficiencies for C2H2 addition and etching by O2 are strongly correlated, but the correlation changes as the NPs passivate. Growth and passivation mechanisms are discussed. [ABSTRACT FROM AUTHOR]

We present the results of an investigation of a highly variable C iv broad absorption line (BAL) feature in spectra of the quasar SBS 1408+544 (z = 2.337) that shows a significant shift in velocity over time. This source was observed as a part of the Sloan Digital Sky Survey (SDSS) Reverberation Mapping project and the SDSS-V Black Hole Mapper Reverberation Mapping project, and has been included in two previous studies, both of which identified significant variability in a high-velocity C iv BAL on timescales of just a few days in the quasar rest frame. Using ∼130 spectra acquired over 8 yr of spectroscopic monitoring with SDSS, we have determined that this BAL is not only varying in strength, but is also systematically shifting to higher velocities. Using cross-correlation methods, we measure the velocity shifts (and corresponding acceleration) of the BAL over a wide range of timescales, measuring an overall velocity shift of Δ v = − 683 − 84 + 89 km s−1 over the 8 yr monitoring period. This corresponds to an average rest-frame acceleration of a = 1.04 − 0.13 + 0.14 cm s−2, though the magnitude of the acceleration on shorter timescales is not constant throughout. We place our measurements in the context of BAL-acceleration models and examine various possible causes of the observed velocity shift. [ABSTRACT FROM AUTHOR]

Active galactic nuclei (AGN) can vary significantly in their rest-frame optical/UV continuum emission, and with strong associated changes in broad line emission, on much shorter timescales than predicted by standard models of accretion disks around supermassive black holes. Most such changing-look or changing-state AGNâ€"and at higher luminosities, changing-look quasars (CLQs)â€"have been found via spectroscopic follow-up of known quasars showing strong photometric variability. The Time Domain Spectroscopic Survey of the Sloan Digital Sky Survey IV (SDSS-IV) includes repeat spectroscopy of large numbers of previously known quasars, many selected irrespective of photometric variability, and with spectral epochs separated by months to decades. Our visual examination of these repeat spectra for strong broad line variability yielded 61 newly discovered CLQ candidates. We quantitatively compare spectral epochs to measure changes in continuum and H β broad line emission, finding 19 CLQs, of which 15 are newly recognized. The parent sample includes only broad line quasars, so our study tends to find objects that have dimmed, i.e., turn-off CLQs. However, we nevertheless find four turn-on CLQs that meet our criteria, albeit with broad lines in both dim and bright states. We study the response of H β and Mg ii emission lines to continuum changes. The Eddington ratios of CLQs are low, and/or their H β broad line width is large relative to the overall quasar population. Repeat quasar spectroscopy in the upcoming SDSS-V black hole Mapper program will reveal significant numbers of CLQs, enhancing our understanding of the frequency and duty cycle of such strong variability, and the physics and dynamics of the phenomenon. [ABSTRACT FROM AUTHOR]

The surface chemistry and optical properties of silica nanoparticles (NPs) were studied using a single nanoparticle mass spectrometer. Initially, silica NPs were transparent to 532 nm excitation, but after brief exposure to a CO2 laser (10.6 μm) their 532 nm absorptivity increased, and when heated they emitted blackbody-like radiation, signalling that their compositions had become more Si-rich. The transformation was also probed by sublimation rate measurements from 1600 K to 2350 K, and the chemistry of the transformed surface was probed by measuring the O2 etching kinetics of pre-heated silica NPs at 1200 and 1300 K. Sublimation was significant at TNP ≥ 1900 K, and the NP optical properties showed further changes as the NPs sublimed. The O2 etching kinetics for pre-heated silica NPs were similar to those previously reported for single Si NPs under identical conditions, with etching efficiency (EEO2) initially increasing with etching time, then dropping by three orders of magnitude as the NP surface passivated by growth of a thermally stable SiO2 layer. The etching and passivation kinetics at different temperatures and O2 pressures are compared, and comparisons are also made to the temperature and time dependence of EEO2 for pre-heated silica, Si, SiC, and carbon NPs. [ABSTRACT FROM AUTHOR]

Buzard, R.M.; Kinsman, N.E.M.; Maio, C.V.; Erikson, L.H.; Jones, B.M.; Anderson, S.; Glenn, R.J.T., and Overbeck, J.R., 2023. Barrier island reconfiguration leads to rapid erosion and relocation of a rural Alaska community. Journal of Coastal Research, 39(4), 625–642. Charlotte (North Carolina), ISSN 0749-0208. Coastal erosion is one of the foremost hazards that circumpolar communities face. Climate change and warming temperatures are anticipated to accelerate coastal change, increasing risk to coastal communities. Most erosion hazard studies for Alaska communities only consider linear erosion and do not anticipate coastal morphologic changes. This study showcases the possibility and consequence of accelerated erosion by examining a shift from stability to rapid erosion that forced the rural Alaska Native village of Meshik (now Port Heiden) to abandon the original town site and relocate inland. A combination of remote sensing, coastal surveys, and community-based monitoring are used to map coastal morphologic changes and identify erosion drivers. The community's shoreline was stable until a protective barrier island eroded away. The exposure to open ocean waves, coupled with unconsolidated, low-density sediments, led to rapid erosion rates averaging 5.8 ± 0.6 m/y from the 1970s to 2020s. The sudden and rapid erosion put great stress on Meshik residents and resulted in the loss of homes, erosion of a safe boat harbor, and pollution of the beach and bay. Erosion of the barrier island coincided with a period of greater storm activity and sea ice decline, but the exact cause could not be determined. Many polar communities are built on or behind barriers and are on erodible soils such as sands and thawing permafrost. This study highlights the need to study, monitor, and predict morphologic change and regime shifts that can bring catastrophic impacts to coastal communities. [ABSTRACT FROM AUTHOR]

Weak emission-line quasars (WLQs) are a subset of type 1 quasars that exhibit extremely weak Ly α + N v λ 1240 and/or C iv λ 1549 emission lines. We investigate the relationship between emission-line properties and accretion rate for a sample of 230 "ordinary" type 1 quasars and 18 WLQs at z < 0.5 and 1.5 < z < 3.5 that have rest-frame ultraviolet and optical spectral measurements. We apply a correction to the H β -based black hole mass (M BH) estimates of these quasars using the strength of the optical Fe ii emission. We confirm previous findings that WLQs' M BH values are overestimated by up to an order of magnitude using the traditional broad-emission-line region size–luminosity relation. With this M BH correction, we find a significant correlation between H β -based Eddington luminosity ratios and a combination of the rest-frame C iv equivalent width and C iv blueshift with respect to the systemic redshift. This correlation holds for both ordinary quasars and WLQs, which suggests that the two-dimensional C iv parameter space can serve as an indicator of accretion rate in all type 1 quasars across a wide range of spectral properties. [ABSTRACT FROM AUTHOR]

Background: Pulse pressure is a dynamic marker of cardiovascular function and is often impaired in patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO). Pulsatile blood flow also serves as a regulator of vascular endothelium, and continuous-flow mechanical circulatory support can lead to endothelial dysfunction. We explored the impact of early low pulse pressure on occurrence of acute brain injury (ABI) in VA-ECMO. Methods: We conducted a retrospective analysis of adults with VA-ECMO at a tertiary care center between July 2016 and January 2021. Patients underwent standardized multimodal neuromonitoring throughout ECMO support. ABI included intracranial hemorrhage, ischemic stroke, hypoxic ischemic brain injury, cerebral edema, seizure, and brain death. Blood pressures were recorded every 15 min. Low pulse pressure was defined as a median pulse pressure < 20 mm Hg in the first 12 h of ECMO. Multivariable logistic regression was performed to investigate the association between pulse pressure and ABI. Results: We analyzed 5138 blood pressure measurements from 123 (median age 63; 63% male) VA-ECMO patients (54% peripheral; 46% central cannulation), of whom 41 (33%) experienced ABI. Individual ABIs were as follows: ischemic stroke (n = 18, 15%), hypoxic ischemic brain injury (n = 14, 11%), seizure (n = 8, 7%), intracranial hemorrhage (n = 7, 6%), cerebral edema (n = 7, 6%), and brain death (n = 2, 2%). Fifty-eight (47%) patients had low pulse pressure. In a multivariable model adjusting for preselected covariates, including cannulation strategy (central vs. peripheral), lactate on ECMO day 1, and left ventricle venting strategy, low pulse pressure was independently associated with ABI (adjusted odds ratio 2.57, 95% confidence interval 1.05–6.24). In a model with the same covariates, every 10-mm Hg decrease in pulse pressure was associated with 31% increased odds of ABI (95% confidence interval 1.01–1.68). In a sensitivity analysis model adjusting for systolic pressure, pulse pressure remained significantly associated with ABI. Conclusions: Early low pulse pressure (< 20 mm Hg) was associated with ABI in VA-ECMO patients. Low pulse pressure may serve as a marker of ABI risk, which necessitates close neuromonitoring for early detection. [ABSTRACT FROM AUTHOR]

Introduction and Methods: We examined the relationship between 24-h pre- and post-cannulation arterial oxygen tension (PaO2) and arterial carbon dioxide tension (PaCO2) and subsequent acute brain injury (ABI) in patients receiving veno-venous extracorporeal membrane oxygenation (VV-ECMO) with granular arterial blood gas (ABG) data and institutional standardized neuromonitoring. Results: Eighty-nine patients underwent VV-ECMO (median age = 50, 63% male). Twenty (22%) patients experienced ABI; intracranial hemorrhage (ICH) was the most common diagnosis (n = 14, 16%). Lower post-cannulation PaO2 levels were significantly associated with ICH (66 vs. 81 mmHg, p = 0.007) and a post-cannulation PaO2 level < 70 mmHg was more frequent in these patients (71% vs. 33%, p = 0.007). PaCO2 parameters were not associated with ABI. By multivariable logistic regression, hypoxemia post-cannulation increased the odds of ICH (OR = 5.06, 95% CI:1.41–18.17; p = 0.01). Conclusion: In summary, lower oxygen tension in the 24-h post-cannulation was associated with ICH development. The precise roles of peri-cannulation ABG changes deserve further investigation, as they may influence the management of VV-ECMO patients. [ABSTRACT FROM AUTHOR]

We report the size‐dependent activity and stability of supported Pt1,4,7,8 for electrocatalytic hydrogen evolution reaction, and show that clusters outperform polycrystalline Pt in activity, with size‐dependent stability. To understand the size effects, we use DFT calculations to study the structural fluxionality under varying potentials. We show that the clusters can reshape under H coverage and populate an ensemble of states with diverse stoichiometry, structure, and thus reactivity. Both experiment and theory suggest that electrocatalytic species are hydridic states of the clusters (≈2 H/Pt). An ensemble‐based kinetic model reproduces the experimental activity trend and reveals the role of metastable states. The stability trend is rationalized by chemical bonding analysis. Our joint study demonstrates the potential‐ and adsorbate‐coverage‐dependent fluxionality of subnano clusters of different sizes and offers a systematic modeling strategy to tackle the complexities. [ABSTRACT FROM AUTHOR]

We report the size‐dependent activity and stability of supported Pt1,4,7,8 for electrocatalytic hydrogen evolution reaction, and show that clusters outperform polycrystalline Pt in activity, with size‐dependent stability. To understand the size effects, we use DFT calculations to study the structural fluxionality under varying potentials. We show that the clusters can reshape under H coverage and populate an ensemble of states with diverse stoichiometry, structure, and thus reactivity. Both experiment and theory suggest that electrocatalytic species are hydridic states of the clusters (≈2 H/Pt). An ensemble‐based kinetic model reproduces the experimental activity trend and reveals the role of metastable states. The stability trend is rationalized by chemical bonding analysis. Our joint study demonstrates the potential‐ and adsorbate‐coverage‐dependent fluxionality of subnano clusters of different sizes and offers a systematic modeling strategy to tackle the complexities. [ABSTRACT FROM AUTHOR]

We present a high-cadence multiepoch analysis of dramatic variability of three broad emission lines (Mg ii, H β, and H α) in the spectra of the luminous quasar (λ L λ (5100 Å) = 4.7 × 1044 erg s−1) SDSS J141041.25+531849.0 at z = 0.359 with 127 spectroscopic epochs over nine years of monitoring (2013–2022). We observe anticorrelations between the broad emission-line widths and flux in all three emission lines, indicating that all three broad emission lines "breathe" in response to stochastic continuum variations. We also observe dramatic radial velocity shifts in all three broad emission lines, ranging from Δ v ∼ 400 km s−1 to ∼800 km s−1, that vary over the course of the monitoring period. Our preferred explanation for the broad-line variability is complex kinematics in the gas in the broad-line region. We suggest a model for the broad-line variability that includes a combination of gas inflow with a radial gradient, an azimuthal asymmetry (e.g., a hot spot), superimposed on the stochastic flux-driven changes to the optimal emission region ("line breathing"). Similar instances of line-profile variability due to complex gas kinematics around quasars are likely to represent an important source of false positives in radial velocity searches for binary black holes, which typically lack the kind of high-cadence data we analyze here. The long-duration, wide-field, and many-epoch spectroscopic monitoring of SDSS-V BHM-RM provides an excellent opportunity for identifying and characterizing broad emission-line variability, and the inferred nature of the inner gas environment, of luminous quasars. [ABSTRACT FROM AUTHOR]

Background: Sport-related concussions (SRCs) affect millions of adolescents and young adults annually in the USA; however, current SRC consensus statements provide limited guidance on academic support for students within higher education. Objective: To generate consensus on appropriate academic recommendations for clinicians, students, and academic stakeholders to support university students during their recovery. Methods: Panelists participated in three stages of a modified Delphi procedure: the first stage included a series of open-ended questions after reviewing a literature review on post-SRC return-to-learn (RTL) in higher education; the second stage asked panelists to anonymously rate the recommendations developed through the first Delphi stage using a 9-point scale; and the final stage offered panelists the opportunity to change their responses and/or provide feedback based on the group's overall ratings. Results: Twenty-two panelists including clinicians, concussion researchers, and academic stakeholders (54.5% female) from 15 institutions and/or healthcare systems participated in a modified Delphi procedure. A total of 42 statements were developed after round one. Following the next two rounds, 27 statements achieved consensus amongst the panel resulting in the four-stage Post-Concussion Collegiate RTL Protocol. Conclusion: There are several unique challenges when assisting university students back to the classroom after SRC. Explicit guidelines on when to seek additional medical care (e.g., if they are experiencing worsening or persistent symptoms) and how to approach their instructor(s) regarding academic support may help the student self-advocate. Findings from the present study address barriers and provide a framework for universities to facilitate a multidisciplinary approach amongst medical and academic stakeholders. [ABSTRACT FROM AUTHOR]

Highly variable and unpredictable precipitation in humid regions makes water management important for consistent potato production. This study assessed the influence of supplemental irrigation (SI) and soil dewatering on potato productivity and profitability in Prince Edward Island, Canada. The average yields of Russet Burbank (RB), Shepody, Kennebec and Goldrush cultivars from 2000 to 2020 (excluding 2018) were conceptualized as the results of an un-replicated experiment with growing season (GS) precipitation representing water supply treatment. GS precipitation varied from 155 to 479 mm, with an average of 338 mm. Yield increased with increasing GS precipitation in the 155–257 mm range (Rainfall Zone 1; 3/20 seasons), became relatively insensitive to GS precipitation in the 258–425 mm range (Rainfall Zone 2; 12/20 seasons), and decreased as GS precipitation increased from 426 to 479 mm (Rainfall Zone 3; 5/20 seasons). Yields responded to GS precipitation following second-order polynomial regressions, with GS precipitation explaining 69%, 65%, 29% and 50% of yield variation for RB, Shepody, Kennebec and Goldrush cultivars, respectively. These yield regression equations predict that SI using a center-pivot system would produce a positive profit in the first half of Rainfall Zone 1 regardless of field size and in the second half of Rainfall Zone 1 in fields over 40 ha. SI would not produce a positive profit in Rainfall Zone 2 regardless of field size because precipitation was high enough that additional water supply would not have resulted in sufficient yield gains to offset the cost of SI. Soil dewatering would be beneficial for optimal production in Rainfall Zone 3 in which precipitation was excessive. The annual variation in precipitation, unpredictability of SI requirements, and unprofitability in most seasons, present a significant financial barrier for the widespread implementation of SI. On the other hand, the gross income gained from increased yields by soil dewatering would fully cover the cost of tile drain installation after only two to three extremely wet seasons, making tile drainage a good investment for consistent production. This study demonstrates that historical rain-fed yield and weather data can be used to assess the economics of potato production with SI and soil dewatering, and provides important insights on potato water management in a humid temperate climate. [ABSTRACT FROM AUTHOR]

Appropriate glucose-stimulated insulin secretion (GSIS) by pancreatic β-cells is an essential component of blood glucose homeostasis. Configuration of β-cells as 3D pseudoislets (PI) improves the GSIS response compared to 2D monolayer (ML) culture. The aim of this study was to determine the underlying mechanisms. MIN6 β-cells were grown as ML or PI for 5 days. Human islets were isolated from patients without diabetes. Function was assessed by GSIS and metabolic capacity using the Seahorse bioanalyser. Connexin 36 was downregulated using inducible shRNA. Culturing MIN6 as PI improved GSIS. MIN6 PI showed higher glucose-stimulated oxygen consumption (OCR) and extracellular acidification (ECAR) rates. Further analysis showed the higher ECAR was, at least in part, a consequence of increased glycolysis. Intact human islets also showed glucose-stimulated increases in both OCR and ECAR rates, although the latter was smaller in magnitude compared to MIN6 PI. The higher rates of glucose-stimulated ATP production in MIN6 PI were consistent with increased enzyme activity of key glycolytic and TCA cycle enzymes. There was no impact of connexin 36 knockdown on GSIS or ATP production. Configuration of β-cells as PI improves GSIS by increasing the metabolic capacity of the cells, allowing higher ATP production in response to glucose. [ABSTRACT FROM AUTHOR]

Objectives: Our institution was affected by a multi-institution, systemwide cyberattack that led to a complete shutdown of major patient care, operational, and communication systems. The attack affected our electronic health record (EHR) system, including all department-specific modules, the laboratory information system (LIS), pharmacy, scheduling, billing and coding, imaging software, internet access, and payroll. Downtime for the EHR lasted 25 days, while other systems were nonfunctional for more than 40 days, causing disruptions to patient care and significantly affecting our laboratories. As more institutions transition to network EHR systems, laboratories are increasingly vulnerable to cyberattack. This article focuses on the approaches we developed in the anatomic pathology (AP) laboratory to continue operations, consequences of the prolonged downtime, and strategies for the future.Methods: Our AP laboratory developed manual processes for surgical and cytopathology processing, redeployed staff, and used resources within the department and of nearby facilities to regain and maintain operations.Results: During the downtime, our AP laboratory processed 1,362 surgical pathology and consult cases as well as 299 cytology specimens and outsourced 1,308 surgical pathology and 1,250 cytology cases.Conclusions: Our laboratory successfully transitioned to downtime processes during a 25-day complete network outage. The crisis allowed for innovative approaches in managing resources. [ABSTRACT FROM AUTHOR]

As main-sequence stars with C > O, dwarf carbon (dC) stars are never born alone but inherit carbon-enriched material from a former asymptotic giant branch (AGB) companion. In contrast to M dwarfs in post-mass-transfer binaries, C2 and/or CN molecular bands allow dCs to be identified with modest-resolution optical spectroscopy, even after the AGB remnant has cooled beyond detectability. Accretion of substantial material from the AGB stars should spin up the dCs, potentially causing a rejuvenation of activity detectable in X-rays. Indeed, a few dozen dCs have recently been found to have photometric variability with periods under a day. However, most of those are likely post-common-envelope binaries, spin–orbit locked by tidal forces, rather than solely spun-up by accretion. Here, we study the X-ray properties of a sample of the five nearest-known dCs with Chandra. Two are detected in X-rays, the only two for which we also detected short-period photometric variability. We suggest that the coronal activity detected so far in dCs is attributable to rapid rotation due to tidal locking in short binary orbits after a common-envelope phase, late in the thermally pulsing (TP) phase of the former C-AGB primary (TP-AGB). [ABSTRACT FROM AUTHOR]

The synthesis of terpenes is a large field of research that is woven deeply into the history of chemistry. Terpene biosynthesis is a case study of how the logic of a modular design can lead to diverse structures with unparalleled efficiency. This work leverages modern nickel-catalyzed electrochemical sp2–sp3 decarboxylative coupling reactions, enabled by silver nanoparticle–modified electrodes, to intuitively assemble terpene natural products and complex polyenes by using simple modular building blocks. The step change in efficiency of this approach is exemplified through the scalable preparation of 13 complex terpenes, which minimized protecting group manipulations, functional group interconversions, and redox fluctuations. The mechanistic aspects of the essential functionalized electrodes are studied in depth through a variety of spectroscopic and analytical techniques. [ABSTRACT FROM AUTHOR]

Few studies have analyzed the Sport Concussion Assessment Tool's (SCAT) utility among athletes whose concussion assessment is challenging. Using a previously published algorithm, we identified possible and probable concussions at <6 h (n = 393 males, n = 265 females) and 24–48 h (n = 323 males, n = 236 females) post-injury within collegiate student-athletes and cadets from the Concussion Assessment, Research, and Education (CARE) Consortium. We applied cluster analysis to characterize performance on the Standard Assessment of Concussion (SAC), Balance Error Scoring System (BESS), and the SCAT symptom checklist for these athletes. Among the cluster sets that best separated acute concussions and normal performances, total symptom number raw score and change and post-traumatic migraine raw score and change score were the most frequent clustering variables across males and females at <6 h and 24–48 h. Similarly, total symptom number raw score and change score and post-traumatic migraine raw score and change score were most significantly different between clusters for males and females at <6 h and 24–48 h. Our results suggest that clinicians should focus on total symptom number, post-traumatic migraine symptoms, and cognitive-fatigue symptoms when assessing possible and probable concussions, followed by the SAC and BESS scores. [ABSTRACT FROM AUTHOR]

• COVID-19 pandemic's stay-at-home orders has downstream effects on care • Increased perforated appendicitis rates were identified during the pandemic • More education is needed to help prevent delays in care due to the pandemic Coronavirus Disease-19 (COVID-19) was declared a pandemic in March 2020. States issued stay-at-home orders and hospitals cancelled non-emergent surgeries. During this time, we anecdotally noticed more admissions for perforated appendicitis. Therefore, we hypothesized that during the months following the COVID-19 pandemic declaration, more children were presenting with perforated appendicitis. This is a retrospective cohort study reviewing pediatric patients admitted at a single institution with acute and/or perforated appendicitis between October 2019 to May 2020. Interval appendectomies were excluded. COVID-19 months were designated as March, April, and May 2020. Additional analysis of March, April, and May 2019 was performed for comparison purposes. Analyzed data included demographics, symptoms, white blood cell count, imaging findings, procedures performed, and perforation status. Statistical analysis was performed. During the study period, 285 patients were admitted with the diagnosis of acute appendicitis with 95 patients being perforated. We identified a significant increase in perforated appendicitis cases in the three COVID-19 months compared with the preceding five months (45.6% vs 26.4%; P <0.001). In addition, a similar significant increase was identified when comparing to the same months a year prior (P = 0.003). No significant difference in duration of pain was identified (P =0.926). The COVID-19 pandemic and its associated stay-at-home orders have had downstream effects on healthcare. Our review has demonstrated a significant increase in the number of children presenting with perforated appendicitis following these stay-at-home ordinances. These results demonstrate that further investigations into the issues surrounding access to healthcare, especially during this pandemic, are warranted. [ABSTRACT FROM AUTHOR]

The charge state of a molecule is the single most prominent attribute ruling out its interactions with the surrounding environment. In a previous study, the retention of acids on the new Celeris™ Arginine (ARG) column was found to be predominantly driven by electrostatics and, specifically, their charge state. Therefore, we analysed 41 compounds in liquid chromatography with ultraviolet detection to study possible relationships between the analytical retention on this phase and the pK a of the acidic solutes. Highly significant relationships were observed indicating either a linear (r 2 = 0.86) or a quadratic (r 2 = 0.89) trend. To improve the throughput of the method, this was transferred to LC mass spectrometry, allowing the analysis of a molecule every 3 mins. The developed method was found to be fast, reliable, accurate, easily automatable and simple to set up. Finally, the analytical column's being industrially manufactured and commercially available offers broad applicability. [Display omitted] • For acids, retention on the ARG phase is dependent on their dissociation constant. • Analytical method was successfully transferred from LC/UV to LC/MS. • This set up allowed high throughput (1 molecules/3 mins) assessment of pKa. [ABSTRACT FROM AUTHOR]

Understanding land surface change in and sediment export out of proglacial landscapes is critical for understanding geohazard and flood risks over engineering timescales and characterizing landscape evolution over geomorphic timescales. We used automated Structure from Motion software to process historical aerial photographs and, with modern lidar data, generated a high-resolution DEM time series with coverage over 10 glacierized watersheds on Mount Baker, Washington, USA for the time period between 1947 and 2015. We measured basin-wide sediment yields and sediment redistribution on hillslopes and in stream channels. Slopes within most measured erosion sites are above theoretical and observed debris-flow thresholds. We observed significant erosion of hillslopes and limited deposition on hillslopes and in stream channels. Sediment delivery ratios during time periods with net erosion averaged 0.73. We determined, consistent with previous field observations, that debris flows originating from moraines are a primary erosion mechanism in proglacial zones on Mount Baker. Time series measurements indicate that temporal variability in erosion rates is associated with climate oscillations, with higher erosion rates during cooler-wetter periods. Basin-wide sediment yield is positively correlated with lithology (r2 = 0.54), hillslope angle (r2 = 0.52), drainage area (r2 = 0.82), and negatively correlated with stream channel slope (r2 = 0.67). Topographic differences between high and low yielding basins indicate that spatial variability in erosion on Mount Baker is sensitive to Pleistocene and Holocene glacial and volcanic activity. Specific sediment yields in six basins averaged 4600 ton/km2/yr, consistent with global measurements in glacierized catchments. Specific sediment yield decreased with increasing basin area, with total loads in the downstream main stem Nooksack River estimated between 480 and 820 ton/km2/yr. Proglacial sediment yields account for between 18 and 32 % of total sediment load in the main stem Nooksack River and exceed contributions by bluff and terrace erosion, which account for between 8 and 13 % of total load. Our findings indicate that erosion in glacierized basins is sensitive to decadal climate oscillations and that high proglacial sediment yields provide an important contribution to river systems downstream, particularly in catchments where upland topography and lithology is favorable. [Display omitted] • Erosion rates approximately follow Pacific Decadal Oscillation (PDO) climate cycles. • Denudation rates in 8 proglacial basins range from 0.2 to 4 mm/yr. • Mean specific sediment yield across 8 proglacial basins is 4600 ton/km2/yr. • Drainage area, hillslope angle, and surface lithology predict sediment yield. • Proglacial headwater basins supply 18–32 % of sediment in the downstream river system. [ABSTRACT FROM AUTHOR]

• The CelerisTM Arginine (ARG) is a mixed-mode stationary phase. • The phase was found to have greater affinity for anionic molecules. • BR analysis was used to deconvolute the retention on ARG into its elementary blocks. • For the neutrals, the most relevant blocks were found to be Size and O. • Bases were poorly retained; retention of acids was found to be electrostatics- driven. CelerisTM Arginine (ARG) is a mixed-mode stationary phase recently released on the market. To characterize its analytical behavior, the retention factors of a pool (n =100, of which 36 neutrals, 26 acids and 38 bases) of pharmaceutically relevant compounds have been measured on this phase over eight percentages (from 10 to 90% v/v) of acetonitrile (MeCN) as organic modifier. The ARG phase exhibited enhanced affinity for the molecules that are in their anionic form at the experimental pH, whilst basic compounds, albeit over a wide range of lipophilicity and pK a values, were on average poorly retained. To dissect the separation mechanism of the ARG phase, the overall analytical retention has been deconvoluted into the individual contributions of intermolecular forces by a QSPR/ Partial Least Square (PLS)/Block Relevance (BR) analysis tool recently developed by us. For the neutrals, the most relevant blocks were found to be Size, describing the interaction due to the dimension of the molecule, and O, representing the solute's hydrogen bond donor properties. The change in sign from positive to negative of the Size block, which occurs between 10% and 20% MeCN, allowed to visually appreciate the switch in the separation mode from reversed phase to normal phase. Some good statistic models for rationalizing the analytical behaviour of neutrals were developed from VS+ descriptors. However, their performance in modelling the analytical retention of acids was substandard, probably due to the intrinsic inefficacy of VS+ descriptors in handling electric charges. This instance was addressed by a complimentary MLR strategy, which led to successfully model the retention of acids on the ARG column and to shed light into their retention mechanism, which seemed to be substantially driven by electrostatics. [ABSTRACT FROM AUTHOR]