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Powered scooters, including electric scooters (e-scooters), have become an increasingly available and popular mode of personal transportation, but the health risks of these devices are poorly explored. We aim to quantify the increase in frequency of powered scooter–associated head and neck region injuries occurring yearly from 2010 to 2019, and to compare the frequency and severity of injury with those involving unpowered scooters. Here we present a retrospective cross-sectional study of all patients with head and neck injuries associated with powered and unpowered scooters seen in emergency departments reporting to the National Electronic Injury Surveillance System (NEISS) database from January 1, 2010 to December 31, 2019. During this time frame, a total of 1,620 injuries associated with powered scooters and a total of 5,675 injuries associated with unpowered scooters were reported to the NEISS. The database estimates these to reflect a nationwide total of 54,036 powered scooter–related injuries and 168,265 unpowered scooter–related injuries. Powered scooter injuries have increased for both children and adults since 2014, and estimated powered scooter injuries (16,243) surpassed estimated unpowered scooter injuries (14,124) when including all age groups for the first time in 2019. In 2019, adults are estimated to have nearly twice as many powered scooter–related head and neck injuries as children (10,884 vs. 5,359, respectively). In 2019, a higher proportion of powered scooter–related injuries involving adults were severe injuries when compared with those involving children (13.3 vs. 5.2%, respectively). Interestingly, unpowered scooters still cause many more estimated injuries in children than powered scooters did during 2019 (11,953 vs. 5,083). We find that powered scooters are now associated with a greater number and severity of head and neck injuries among the adult population than the pediatric population. But unpowered scooters still cause more head and neck injuries than powered scooters in the pediatric population. [ABSTRACT FROM AUTHOR]

The Canadian Cordillera marks a transition region from the current plate boundary through the Phanerozoic Cordilleran orogen to the Precambrian cratons. Knowledge of the subsurface structure of western Canada has been greatly advanced by seismological investigations during the past two decades, pioneered by the Lithoprobe project and, more recently, by regional passive seismic arrays. In this study, we construct a new model (WCANM22) of crustal thickness and P‐ to S‐wave velocity ratio, or Vp/Vs, by compiling receiver function data from 473 stations and existing constraints from over 2,600‐km long active source experiments. Our model covers a broad swath (about 1/4) of the land area of North America (105°–140°W, 48°–72°N) and shows an overall flat Moho beneath the Cordillera with an average depth of ∼36 km and a standard deviation of 3 km across orogenic belts. This study provides a comprehensive catalog of Vp/Vs in western Canada and reveals a moderate correlation between Poisson's ratio and the age of crustal domains. The average Vp/Vs values are 1.72, 1.79, and 1.82 for the Phanerozoic Cordillera, Proterozoic Cratons, and Archean‐aged Medicine Hat Block, respectively, suggesting continued modifications to crustal composition through episodic tectonothermal events. This distinct trend in western Canada sheds new light on the debated role of secular changes in the composition of continental crust. Plain Language Summary: The crust of western Canada consists of complex tectonic domains that collided during a protracted geological history dating back to 4 billion years ago. To uncover crustal structures and the associated tectonic processes, we systematically determine the depth to the base of the crust (Moho depth) and compressional‐to‐shear seismic wave speed ratio (Vp/Vs) beneath 473 seismic stations integrated with the results from existing active source experiments. Along a northwest‐southeast profile, Vp/Vs ratios exhibit a gradually increasing trend with the age of the crust. This variation in Vp/Vs may be caused by modifications to the crustal composition during the geological evolution of western Canada. Key Points: We construct a new model of crustal thickness and Vp/Vs of western Canada from integrated active and passive seismic constraintsWe propose that increased Vp/Vs with the age of tectonic domains may reflect a secular change in crustal compositionWe highlight key tectonic boundaries at crustal depth formed during the collision and assembly of cratons [ABSTRACT FROM AUTHOR]

Although the relationships among acute stress, cardiorespiratory fitness (CRF), and cognitive function have been examined, whether CRF is related to behavioral and neuroelectric indices of inhibitory control following acute stress remains unknown. The purpose of the current study was to investigate the combined influence of acute stress and CRF on inhibitory control. Participants, aged 20–30 years, were stratified into the Higher‐Fit (n = 31) and the Lower‐Fit (n = 32) groups, and completed a Stroop task following the modified Maastricht Acute Stress Test (MAST) in the stress condition and the sham‐MAST in the non‐stress condition, during which electroencephalography was recorded. Behavioral (i.e., response time and accuracy) and neuroelectric (N2 and P3b components of the event‐related potential) outcomes of inhibitory control were obtained. While the Higher‐Fit group demonstrated shorter response times and higher accuracy than the Lower‐Fit group following both the MAST and the sham‐MAST, they also exhibited selective benefits of acute stress on inhibitory control performance (i.e., decreased response times and diminished interference scores). CRF‐dependent alterations in neuroelectric indices were also observed, with the Higher‐Fit group displaying smaller N2 and greater P3b amplitudes than the Lower‐Fit group following the sham‐MAST, and increased N2 and attenuated P3b amplitudes following the MAST. Collectively, these findings not only confirm the positive relationship between CRF and inhibitory control but also provide novel insights into the potential influence of CRF on inhibitory control and associated neuroelectric activity following acute stress. Distinct from previous research that analyzed the effects of cardiorespiratory fitness (CRF) and acute stress on inhibitory control in isolation, our research innovatively examined the relationship between CRF and inhibitory control after acute stress. Our findings revealed that individuals with higher CRF not only inherently possess superior inhibitory control than those with lower CRF under non‐stress conditions but also demonstrate markedly enhanced performance after acute stress. This advancement in understanding the multifaceted relationship between CRF and inhibitory control under varying stress conditions paves the way for the development of targeted strategies to leverage CRF to optimize inhibitory control in stress‐prone environments. [ABSTRACT FROM AUTHOR]

Abstract This study investigates lateral variations in density contrast across the 660‐km discontinuity, which is critical for understanding mantle convection and composition. We produce a global map of density jump, with values ranging from 3.8% to 9.3%, at the mineralogical phase boundary by applying inversions of amplitude variations with offset to underside S reflections. Our observations reveal a global average velocity jump of 4.1% and a density jump of 5.3%, favoring a pyrolitic bulk composition. Near major subduction zones, most notably the western Pacific and South America, we identify reduced density jumps in regions of depressed 660‐km discontinuity, consistent with basalt fractions greater than 30% in a mechanically mixed mantle. The causal association between density jump and compositional changes is further supported by a moderate correlation between lateral variations in density jump and those of water content anomalies.

We report a case a 70-year-old female presenting with abdominal pain who has a cystic duct coursing medial to the common bile duct before anastomosing just proximal to the ampulla. Low medial insertion of the cystic duct is a rare anatomic variant that is easily misidentified on imaging studies and may complicate surgical and percutaneous intervention. It can be identified by pre-operative imaging modalities such as magnetic resonance cholangiopancreatography.

BackgroundOzone is a ubiquitous air pollutant with increasing concentrations in many populous regions. Toxicological studies show that ozone can cause oxidative stress and increase insulin resistance. These pathways may contribute to metabolic changes and diabetes formation. In this paper, we investigate the association between ozone and incident type 2 diabetes in a large cohort of African American women.MethodsWe used Cox proportional hazards models to calculate hazard ratios (HRs) for incident type 2 diabetes associated with exposure to ozone in a cohort of 45,231 African American women living in 56 metropolitan areas across the United States. Ozone levels were estimated using the U.S. EPA Models-3/Community Multiscale Air Quality (CMAQ) predictions fused with ground measurements at a resolution of 12km for the years 2007-2008.ResultsThe HR per interquartile range increment of 6.7ppb of ozone was 1.18 (95% CI 1.04-1.34) for incident diabetes in adjusted models. This association was unaltered in models that controlled for fine particulate matter with diameter

Stem cells in many tissues sustain themselves by entering a quiescent state to avoid genomic insults and to prevent exhaustion caused by excessive proliferation. In the mammary gland, the identity and characteristics of quiescent epithelial stem cells are not clear. Here, we identify a quiescent mammary epithelial cell population expressing high levels of Bcl11b and located at the interface between luminal and basal cells. Bcl11bhigh cells are enriched for cells that can regenerate mammary glands in secondary transplants. Loss of Bcl11b leads to a Cdkn2a-dependent exhaustion of ductal epithelium and loss of epithelial cell regenerative capacity. Gain- and loss-of-function studies show that Bcl11b induces cells to enter the G0 phase of the cell cycle and become quiescent. Taken together, these results suggest that Bcl11b acts as a central intrinsic regulator of mammary epithelial stem cell quiescence and exhaustion and is necessary for long-term maintenance of the mammary gland.

Neuromyelitis optica spectrum disorder is an autoimmune disease, causing severe disability due to relapses, but recent mortality data are limited. Among 396 patients seropositive for anti‐aquaporin‐4 antibody from 2014 to 2020 in the United Kingdom, 39 deaths occurred: 19 (48.7%) were unrelated to disease; 14 (35.9%) were severe disability‐ or relapse‐related; and 4 (10.3%) were attributed to malignancy/infection. Mean annual mortality was 1.92% versus 0.63% in the matched population. The standardized mortality ratio was 3.04 (95% confidence interval 1.67–5.30) with 1.29% excess mortality per year in patients. Median Expanded Disability Status Scale before death was 7.0. Results highlight the importance of preventing relapses that drive disability. [ABSTRACT FROM AUTHOR]

IntroductionSubstantial research has been dedicated to understanding the reasons for the dramatic rise in obesity rates in the U.S. in the last 2 decades. Animal studies and epidemiologic studies in children have suggested that air pollution might contribute to weight gain. This study investigates the association between ambient air pollution and weight gain over 16 years of follow-up (1995-2011) in a large cohort of African-American women in the U.S.MethodsThis study assessed associations of fine particulate matter, ozone, and nitrogen dioxide with weight gain using a linear random effects model. All analyses were conducted in 2015.ResultsThere was no statistically significant association between weight change and fine particulate matter (mean weight change over 16 years per interquartile range [2.9 μg/m(3)], 0.12 kg; 95% CI=-0.10, 0.35) and ozone (0.16 kg per interquartile range [6.7 ppb]; 95% CI=-0.11, 0.43). There was a small decrease in weight associated with nitrogen dioxide (-0.50 per interquartile range [9.7 ppb]; 95% CI=-0.77, -0.23).ConclusionsThe results do not provide support for an association of air pollution with weight gain in African-American adult women.

While laboratory studies show that air pollutants can potentiate insulin resistance, the epidemiologic evidence regarding the association of air pollution with diabetes incidence is conflicting. The purpose of the present study was to assess the association of the traffic-related nitrogen dioxide (NO2) with the incidence of diabetes in a longitudinal cohort study of African American women. We used Cox proportional hazards models to calculate hazard ratios and 95% confidence intervals (CI) for diabetes associated with exposure to NO2 among 43,003 participants in the Black Women's Health Study (BWHS). Pollutant levels at participant residential locations were estimated with 1) a land use regression model for participants living in 56 metropolitan areas, and 2) a dispersion model for participants living in 27 of the cities. From 1995 to 2011, 4387 cases of diabetes occurred. The hazard ratios per interquartile range of NO2 (9.7 ppb), adjusted for age, metropolitan area, education, vigorous exercise, body mass index, smoking, and diet, were 0.96 (95% CI 0.88-1.06) using the land use regression model estimates and 0.94 (95% CI 0.80, 1.10) using the dispersion model estimates. The present results do not support the hypothesis that exposure to NO2 contributes to diabetes incidence in African American women.

Numerous observational studies have assessed the association between ambient air pollution and chronic disease incidence, but there is no uniform approach to create an exposure metric that captures the variability in air pollution through time and determines the most relevant exposure window. The purpose of the present study was to assess ways of modeling exposure to air pollution in relation to incident hypertension. We simulated data on incident hypertension to assess the performance of six air pollution exposure metrics, using characteristics from the Black Women's Health Study. Each metric made different assumptions about how to incorporate time trends in pollutant data, and the most relevant window of exposure. We use observed values for particulate matter ≤ 2.5 microns (PM2.5) for this cohort to create the six exposure metrics and fit Cox proportional hazards models to the simulated data using the six metrics. The optimal exposure metric depends on the underlying association between PM2.5 and disease, which is unknown. Metrics that incorporate exposure information from multiple years tend to be more robust and suffer from less bias. This study provides insight into factors that influence the metric used to quantifying exposure to PM2.5 and suggests the need for careful sensitivity analyses.

BackgroundClinical studies have shown that exposure to fine particulate matter (PM2.5) can increase insulin resistance and blood pressure. The epidemiologic evidence for an association of PM2.5 exposure with the incidence of type 2 diabetes or hypertension is inconsistent. Even a modest association would have great public health importance given the ubiquity of exposure and high prevalence of the conditions.MethodsWe used Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident type 2 diabetes and hypertension associated with exposure to PM2.5 in a large cohort of African American women living in 56 metropolitan areas across the US, using data from the Black Women's Health Study. Pollutant levels were estimated at all residential locations over follow-up with a hybrid model incorporating land use regression and Bayesian Maximum Entropy techniques.ResultsDuring 1995 to 2011, 4,387 cases of diabetes and 9,570 cases of hypertension occurred. In models controlling for age, questionnaire cycle, and metro area, there were positive associations with diabetes (HR = 1.13, 95% CI = 1.04, 1.24) and hypertension (HR = 1.06, 95% CI = 1.00, 1.12) per interquartile range of PM2.5 (2.9 μg/m). Multivariable HRs, however, were 0.99 (95% CI = 0.90, 1.09) for diabetes and 0.99 (95% CI = 0.93, 1.06) for hypertension.ConclusionsOur results provide little support for an association of PM2.5 with diabetes or hypertension incidence.