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Computer modeling and simulation are the cornerstones of product design and development in the automotive industry. Computer-aided engineering tools have improved to the extent that virtual testing may lead to significant reduction in prototype building and testing of vehicle designs. In order to make this a reality, we need to assess our confidence in the predictive capabilities of simulation models. As a first step in this direction, this paper deals with developing measures and a metric to compare time histories obtained from simulation model outputs and experimental tests. The focus of the work is on vehicle safety applications. We restrict attention to quantifying discrepancy between time histories as the latter constitute the predominant form of responses of interest in vehicle safety considerations. First, we evaluate popular measures used to quantify discrepancy between time histories in fields such as statistics, computational mechanics, signal processing, and data mining. Three independent error measures are proposed for vehicle safety applications, associated with three physically meaningful characteristics (phase, magnitude, and slope), which utilize norms, cross-correlation measures, and algorithms such as dynamic time warping to quantify discrepancies. A combined use of these three measures can serve as a metric that encapsulates the important aspects of time history comparison. It is also shown how these measures can be used in conjunction with ratings from subject matter experts to build regression-based validation metrics. [DOI: 10.1115/1.4002478]

Background: The incidence of obesity in African Americans (AAs) is higher than in non-AA in the USA. Previous studies using large national databases report that AA patients have worse outcomes than non-AA patients., Objectives: To assess perioperative outcomes among AA patients after MBS at a center of excellence (COE) that serves a large, diverse patient population., Setting: University Hospital METHODS: A retrospective analysis was performed on patients undergoing MBS between 2010 and 2020 at our two accredited MBSAQIP (Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program) COEs where the AA population makes up over 35% of the population. Preoperative variables were compared using unpaired t-test or chi-squared test where appropriate. Thirty-day outcomes were compared following propensity score matching (exact algorithm) of demographics and comorbidities., Results: Overall, 5742 patients (AA = 2058, 36%) had Roux-en-Y gastric bypass (AA = 1028, 26%) or sleeve gastrectomy (AA = 1030, 27%). AA patients were more often female (90.2% vs. 80.2%, p < 0.001) and had higher rates of hypertension (56.3% vs. 47.8%, p < 0.001), while non-AA patients had higher rates of hyperlipidemia (27.3% vs. 20.7%, p < 0.001) and obstructive sleep apnea (41.2% vs. 37.1%, p = 0.0024). Matched data showed that AA patients had higher rates of pulmonary embolism (PE) (0.3% vs. 0.1%, p = 0.020) and more emergency department visits (7.0% vs. 5.1%, p = 0.012) but no differences in mortality, readmission, reintervention, or reoperation rates., Conclusions: In a diverse area, AA patients who underwent MBS had similar perioperative outcomes compared to non-AA patients except that they experienced higher rates of PE. They also experienced higher rates of emergency department visits but had similar readmission rates., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Freestanding emergency departments have risen in popularity as a means to expand access to care. Although some evaluation of freestanding emergency department utility in specific patient populations exists, management of surgical patients via remote triage and disposition has not been previously described. We report our experience with remote triage to discharge home, level I trauma center, or community hospital admission for general surgery patients who present to an affiliated freestanding emergency department., Methods: A retrospective cohort study of patients presenting to freestanding emergency departments requiring surgical consultation between 2016 and 2021 was conducted. Outcomes included disposition, length of stay, surgical intervention, 30-day mortality, and readmission. Undertriage and overtriage rates were calculated and defined as the following: (1) discharge undertriage-discharge home with 30-day emergency department visit/readmission; 2) transfer undertriage-transfers to community hospital requiring transfer to trauma center; and (3) overtriage-admissions <24 hours without surgery., Results: Of 1,105 patients, 15% were discharged home, 27% were transferred to trauma centers, and 58% were transferred to community hospitals. Patients admitted to trauma centers were older and had higher acuity pathology, whereas patients admitted to community hospitals had higher operative rates with shorter lengths of stay, operating room time, 30-day readmission, and mortality. Transfer undertriage was 0.9% (n = 6), with only 1 patient requiring transfer from a community hospital to a trauma center for disease acuity. Discharge undertriage was 12% (n = 20) due to worsening or persistent pathology. Overtriage was 5.5% (n = 52), with most having a partial small bowel obstruction or ambiguous diagnostic imaging requiring observation., Conclusion: Remote surgery triage at freestanding emergency departments, without an in-person examination, demonstrated both low undertriage and overtriage rates, reflecting appropriate triage practices., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Freestanding emergency departments (FSEDs) have generated improved hospital metrics, including decreased ED wait times and increased patient selection. Patient outcomes and process safety have not been evaluated. This study investigates the safety of FSED virtual triage in the emergency general surgery (EGS) patient population., Methods and Procedures: A retrospective review evaluated all adult EGS patients admitted to a community hospital between January 2016 and December 2021 who either presented at a FSED and received virtual evaluation from a surgical team (fEGS) or presented at the community hospital emergency department and received in-person evaluation from the same surgical group (cEGS). Patients' demographics, acute care utilization history, and clinical characteristics at the onset of the index visit were used to build a propensity score model and stabilized Inverse Probability of Treatment Weights (IPTW) were used to create a weighted sample. Multivariable regression models were then employed to the weighted sample to evaluate the treatment effect of virtual triage compared to in-person evaluation on short-term outcomes, including length of stay (LOS) and 30-day readmission and mortality. Variables which occurred during the index visit (such as surgery duration and type of surgery) were adjusted for in the multivariable analyses., Results: Of 1962 patients, 631 (32.2%) were initially evaluated virtually (fEGS) and 1331 (67.8%) underwent an in-person evaluation (cEGS). Baseline characteristics demonstrated significant differences between the cohorts in gender, race, payer status, BMI, and CCI score. Baseline risks were well balanced in the IPTW-weighted sample (SD range 0.002-0.18). Multivariable analysis found no significant differences between the balanced cohorts in 30-day readmission, 30-day mortality, and LOS (p > 0.05 for all)., Conclusion: Patients who undergo virtual triage have similar outcomes to those who undergo in-person triage for EGS diagnoses. Virtual triage at FSED for these EGS patients may be an efficient and safe means for initial evaluation., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Traumatic brain injury can be caused by head impacts, but many brain injury risk estimation models are not equally accurate across the variety of impacts that patients may undergo, and the characteristics of different types of impacts are not well studied. We investigated the spectral characteristics of different head impact types with kinematics classification., Methods: Data were analyzed from 3262 head impacts from lab reconstruction, American football, mixed martial arts, and publicly available car crash data. A random forest classifier with spectral densities of linear acceleration and angular velocity was built to classify head impact types (e.g., football, car crash, mixed martial arts). To test the classifier robustness, another 271 lab-reconstructed impacts were obtained from 5 other instrumented mouthguards. Finally, with the classifier, type-specific, nearest-neighbor regression models were built for brain strain., Results: The classifier reached a median accuracy of 96% over 1000 random partitions of training and test sets. The most important features in the classification included both low- and high-frequency features, both linear acceleration features and angular velocity features. Different head impact types had different distributions of spectral densities in low- and high-frequency ranges (e.g., the spectral densities of mixed martial arts impacts were higher in the high-frequency range than in the low-frequency range). The type-specific regression showed a generally higher R 2 value than baseline models without classification., Conclusion: The machine-learning-based classifier enables a better understanding of the impact kinematics spectral density in different sports, and it can be applied to evaluate the quality of impact-simulation systems and on-field data augmentation., Competing Interests: Competing interests The authors declare that they have no competing interests., (Copyright © 2023. Production and hosting by Elsevier B.V.)

Introduction: Biliopancreatic diversion with duodenal switch (BPD-DS) has often been reserved for patients with BMI > 50 kg/m 2 . We aim to assess the safety of BPD-DS in patients with morbid obesity (BMI 3 35 kg/m 2 and < 50 kg/m 2 ) using a 150-cm common channel (CC), 150-cm Roux limb, and 60-fr bougie., Methods: A retrospective review was performed on patients with a BMI < 50 mg/k 2 who underwent a BPD-DS in 2016-2019 at a single institution. Limb lengths were measured with a laparoscopic instrument with minimal tension. Sleeve gastrectomy was created with 60-fr bougie. Variables were compared using paired t test, Chi-square analysis or repeated measures ANOVA where appropriate., Results: Forty-five patients underwent BPD-DS. CC lengths and Roux limb lengths were 158 ± 20 cm and 154 ± 18 cm, respectively. Preoperative BMI was 44.9 ± 2.3 kg/m 2 and follow-up was 2.7 ± 1.4 years. One patient required reoperation for bleeding and died from multiorgan failure and delayed sleeve leak. There was 1 (2.2%) readmission for contained anastomotic leak and 2 ED visits (4.5%) within 30 days. There were no marginal ulcers, limb length revisions, or need for parental nutrition. Percent excess weight loss was 67.2 ± 19.7%. 88.9% (N = 8), 86.6% (N = 13), and 55.5% (N = 5) of patients had resolution or improvement of their diabetes mellitus type II, hypertension, and hyperlipidemia, respectively. 40% (N = 4) of patients had resolution of their gastroesophageal reflux disease (GERD) and 11.4% (N = 5) developed de novo GERD. 32% (N = 14) of patients had vitamin D deficiency and 25% (N = 11) experienced zinc deficiency., Conclusion: BPD-DS may be considered in patients with BMI < 50 kg/m 2 with 150-cm CC, 150-cm Roux limb, and a 60-fr bougie sleeve gastrectomy. There was sustained weight loss and no protein calorie malnutrition, but Vitamin D and zinc deficiency remained a challenge. Careful patient selection and proper counseling of the risks and benefits are necessary., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Obesity rates in Hispanics and African Americans (AAs) are higher than in Caucasians in the USA, yet the rate of metabolic and bariatric surgery (MBS) for weight loss remains lower for both Hispanics and AAs., Methods: Patient demographics and outcomes of adult AA and Hispanic patients undergoing sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) procedures were analyzed using the MBSAQIP dataset [2015-2018] using unmatched and propensity-matched data., Results: In total, 173,157 patients were included, of whom 98,185 were AA [56.7%] [21,163-RYGB; 77,022-SG] and 74,972 were Hispanic [43.3%] [20,282-RYGB; 54,690-SG]). Preoperatively, the AA cohort was older, had more females, and higher BMIs with higher rates of all tracked obesity-related medical conditions except for diabetes, venous stasis, and prior foregut surgery. Intra- and postoperatively, AAs were more likely to experience major complications including unplanned ICU admission, 30-day readmission/reintervention, and mortality. After propensity matching, the differences in ED visits, treatment for dehydration, 30-day readmission, 30-day intervention, and pulmonary embolism remained for both SG and RYGB cohorts. Progressive renal insufficiency and ventilator use lost statistical significance in both cohorts. Conversely, 30-day reoperation, postoperative ventilator requirement, unplanned intubation, unplanned ICU admission, and mortality lost significance in the RYGB cohort, but not SG patients., Conclusion: Outcomes for AA patients were worse than for Hispanic patients, even after propensity matching. After matching, differences in major complications and mortality lost significance for RYGB, but not SG. These data suggest that outcomes for RYGB may be driven by the presence and severity of pre-existing patient-related factors., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: For patients with super obesity (BMI > 50 kg/m 2 ), biliopancreatic diversion/duodenal switch (BPD/DS) can be an effective bariatric operation. Technical challenges and patient safety concerns, however, have limited its use as a primary procedure. This study sought to assess the safety of primary versus revisional BPD/DS., Materials and Methods: The MBSAQIP database was queried for primary and revisional BPD/DS (2015-2018). Inclusion criteria were patients ≥ 18 years of age, BMI > 50 kg/m 2 , and with no concurrent procedures. Preoperative variables were compared using a chi-square test or Wilcoxon two-sample tests. Multivariate logistic or robust linear regression models were used to compare outcomes., Results: There were 3,378 primary BPD/DS and 487 revisional BPD/DS patients. Primary BPD/DS patients had higher BMI (56.5 [IQR4.4] versus 54.8 [IQR4] kg/m 2 , p < 0.0001) and had more diabetes mellitus type II (29.1% versus 17.2%, p < 0.0001). Intraoperatively, revisional BPD/DS had longer operative time (165 [IQR47] min versus 139 [IQR100] min, p < 0.0001). After adjusting for preoperative characteristics, there was no difference in 30-day readmission or ED visits (primary 12.9% versus revisional 14.6%), reoperation or reintervention (primary 5.7% versus revisional 7.8%), or mortality (primary 0.4% versus revisional 0.6%). In contrast, the revisional BPD/DS patients had higher odds of major morbidity (primary 3.4% versus revisional 5.3%, OR 1.9, CI 1.1-3.2, p = 0.019)., Conclusions: Revisional BPD/DS is associated with higher morbidity than primary BPD/DS in patients with super obesity. These patients should thus be counselled appropriately when choosing a primary or revisional bariatric procedure., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Roux-en-Y gastric bypass (RYGB) is an established surgical treatment for obesity. Variations in limb length during RYGB procedures have been investigated for optimizing weight loss while minimizing nutritional deficiencies. The role of the total alimentary limb length (TALL; Roux limb plus common channel [CC]), however, is poorly defined., Objective: Compare TALL in RYGB procedures for weight loss outcomes and malnutrition., Setting: Systematic review., Methods: Ovid Medline and PubMed databases were searched for entries between 1993 and 2020. Search terms included "gastric bypass" and "TALL." Two independent reviewers screened the results., Results: A total of 21 studies measured TALL in RYGB. Of these, 4 of 6 reported a relationship between TALL and weight loss. Additionally, 11 studies reported that when TALL was ≤400 cm and CC <200 cm, 3.4% to 63.6% of patients required limb lengthening for protein malnutrition., Conclusions: The majority of studies on RYGB do not report TALL length. There is some evidence that weight loss is affected by shortening TALL, while a TALL ≤400 cm with CC<200 should be avoided due to severe protein malnutrition. More studies on the effect of TALL are needed., (Copyright © 2021 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Regionalization of emergency general surgery (EGS) has primarily focused on expediting care of high acuity patients through interfacility transfers. In contrast, triaging low-risk patients to a nondesignated trauma facility has not been evaluated. This study evaluates a 16-month experience of a five-surgeon team triaging EGS patients at a tertiary care, Level I trauma center (TC) to an affiliated community hospital 1.3 miles away., Methods: All EGS patients who presented to the Level I TC emergency department from January 2020 to April 2021 were analyzed. Patients were screened by EGS surgeons covering both facilities for transfer appropriateness including hemodynamics, resource need, and comorbidities. Patients were retrospectively evaluated for disposition, diagnosis, comorbidities, length of stay, surgical intervention, and 30-day mortality and readmission., Results: Of 987 patients reviewed, 31.5% were transferred to the affiliated community hospital, 16.1% were discharged home from the emergency department, and 52.4% were admitted to the Level I TC. Common diagnoses were biliary disease (16.8%), bowel obstruction (15.7%), and appendicitis (14.3%). Compared with Level I TC admissions, Charlson Comorbidity Index was lower (1.89 vs. 4.45, p < 0.001) and length of stay was shorter (2.23 days vs. 5.49 days, p < 0.001) for transfers. Transfers had a higher rate of surgery (67.5% vs. 50.1%, p < 0.001) and lower readmission and mortality (8.4% vs. 15.3%, p = 0.004; 0.6% vs. 5.0%, p < 0.001). Reasons not to transfer were emergency evaluation, comorbidity burden, operating room availability, and established care. No transfers required transfer back to higher care (under-triage). Bed days saved at the Level I TC were 693 (591 inpatients). Total operating room minutes saved were 24,008 (16,919, between 7:00 am and 5:00 pm)., Conclusion: Transfer of appropriate patients maintains high quality care and outcomes, while improving operating room and bed capacity and resource utilization at a tertiary care, Level I TC. Emergency general surgery regionalization should consider triage of both high-risk and low-risk patients., Level of Evidence: Prospective comparative cohort study, Level II., (Copyright © 2021 American Association for the Surgery of Trauma.)

Efficient brain strain estimation is critical for routine application of a head injury model. Lately, a convolutional neural network (CNN) has been successfully developed to estimate spatially detailed brain strains instantly and accurately in contact sports. Here, we extend its application to automotive head impacts, where impact profiles are typically more complex with longer durations. Head impact kinematics (N=458) from two public databases were used to generate augmented impacts (N=2694). They were simulated using the anisotropic Worcester Head Injury Model (WHIM) V1.0, which provided baseline elementwise peak maximum principal strain (MPS). For each augmented impact, rotational velocity ( v rot ) and the corresponding rotational acceleration ( a rot ) profiles were concatenated as static images to serve as CNN input. Three training strategies were evaluated: 1) "baseline", using random initial weights; 2) "transfer learning", using weight transfer from a previous CNN model trained on head impacts drawn from contact sports; and 3) "combined training", combining previous training data from contact sports (N=5661) for training. The combined training achieved the best performances. For peak MPS, the CNN achieved a coefficient of determination (R 2 ) of 0.932 and root mean squared error (RMSE) of 0.031 for the real-world testing dataset. It also achieved a success rate of 60.5% and 94.8% for elementwise MPS, where the linear regression slope, k, and correlation coefficient, r, between estimated and simulated MPS did not deviate from 1.0 (when identical) by more than 0.1 and 0.2, respectively. Cumulative strain damage measure (CSDM) from the CNN estimation was also highly accurate compared to those from direct simulation across a range of thresholds (R 2 of 0.899-0.943 with RMSE of 0.054-0.069). Finally, the CNN achieved an average k and r of 0.98±0.12 and 0.90±0.07, respectively, for six reconstructed car crash impacts drawn from two other sources independent of the training dataset. Importantly, the CNN is able to efficiently estimate elementwise MPS with sufficient accuracy while conventional kinematic injury metrics cannot. Therefore, the CNN has the potential to supersede current kinematic injury metrics that can only approximate a global peak MPS or CSDM. The CNN technique developed here may offer enhanced utility in the design and development of head protective countermeasures, including in the automotive industry. This is the first study aimed at instantly estimating spatially detailed brain strains for automotive head impacts, which employs >8.8 thousand impact simulations generated from ~1.5 years of nonstop computations on a high-performance computing platform.

Purpose: Patients undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) are at risk of developing strictures of the gastrojejunal anastomosis (GJA). Several variables can affect this, one of which may be the method of anastomosis. Between 2010 and 2014, our institution utilized three different anastomotic techniques for creating the GJA (25 mm end-to-end circular-stapled (CS), linear-stapled (LS), and robotic hand sewn (HS)). Our objectives were to compare the method of GJA relative to the subsequent development of anastomotic stricture., Methods: We queried our electronic health record for all patients who underwent an upper endoscopy (EGD) after RYGB (2010-2014). Patient charts were retrospectively reviewed for type of GJA, weight loss, complications, interventions, and revisions of the GJA., Results: In total, 1112 RYGB were performed at our institute, and 17.4% of patients (194/1112) had an upper endoscopy (EGD). Overall, 3.1% (34/1112) were found to have a stricture of the GJA. Patients undergoing a CS, LS, and HS anastomosis had GJA stricture rates of 4.9%, 0.5%, and 1.2% respectively (CS to LS (p < 0.05), p = NS among CS vs. HS, and LS vs. HS). The rate of GJA revision was 1.5%, 0.5%, and 0.1% (p = NS). In patients who had an EGD, excess BMI loss was 57.4%, 64.6%, and 59.2% (p = NS). In patients symptomatic from strictures, excess BMI loss was 69.4%, 83%, and 63.5% respectively (p = NS)., Conclusion: The anastomotic technique for creating of the GJA may impact the formation of strictures. Based on our experience, gastrojejunostomies created with a 2-mm EEA-stapling technique are at higher risk of strictures., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Brain tissue deformation resulting from head impacts is primarily caused by rotation and can lead to traumatic brain injury. To quantify brain injury risk based on measurements of kinematics on the head, finite element (FE) models and various brain injury criteria based on different factors of these kinematics have been developed, but the contribution of different kinematic factors has not been comprehensively analyzed across different types of head impacts in a data-driven manner. To better design brain injury criteria, the predictive power of rotational kinematics factors, which are different in (1) the derivative order (angular velocity, angular acceleration, angular jerk), (2) the direction and (3) the power (e.g., square-rooted, squared, cubic) of the angular velocity, were analyzed based on different datasets including laboratory impacts, American football, mixed martial arts (MMA), NHTSA automobile crashworthiness tests and NASCAR crash events. Ordinary least squares regressions were built from kinematics factors to the 95% maximum principal strain (MPS95), and we compared zero-order correlation coefficients, structure coefficients, commonality analysis, and dominance analysis. The angular acceleration, the magnitude and the first power factors showed the highest predictive power for the majority of impacts including laboratory impacts, American football impacts, with few exceptions (angular velocity for MMA and NASCAR impacts). The predictive power of rotational kinematics about three directions (x: posterior-to-anterior, y: left-to-right, z: superior-to-inferior) of kinematics varied with different sports and types of head impacts., (© 2021. Biomedical Engineering Society.)

Background: Marginal ulceration (MU) and bleeding are possible complications following laparoscopic Roux-en-Y gastric bypass (RYGB). Our institution utilizes three techniques for performing the gastrojejunal anastomosis (GJA), providing a means to compare postoperative MU and bleeding as it relates to GJA technique., Objectives: We sought to analyze the incidence of MU and bleeding between the 25-mm end-to-end anastomosis (EEA) stapler, linear stapler (LS), and robotic hand-sewn (RHS) GJA techniques., Methods: Electronic health records for all patients who had an upper endoscopy (EGD) after RYGB were queried (2010-2014). Charts were retrospectively reviewed for type of GJA, complications, endoscopic interventions, and smoking and NSAID use., Results: Out of 1112 RYGBs, the GJA was created using an EEA, LS, or RHS approach in 58.6%, 33.6%, and 7.7% of patients, respectively. 17.4% had an EGD (19.9% EEA, 13.9% LS, and 14.0% RHS). Incidence of MU was 7.3% (9.3% EEA, 4.8% LS, and 5.8% RHS). Rates of EGD and MU were significantly higher after EEA vs. LS GJA (p<0.05). The bleeding rate was 1.5%, [1.1% EEA, 2.1% LS, and 2.3% RHS (p=NS)]. MU within 90 days of RYGB occurred in 4.1%, 0.8%, and 4.7%, respectively (p<0.05 for EEA vs LS only). NSAID and cigarette use were identified in 29.3%, 38.9%, and 60% and 17.2%, 22.2%, and 20%, respectively, for the EEA, LS, and RHS GJA (p=NS)., Conclusion: The method of GJA has an impact on rate of MU formation. A GJA fashioned with a 25-mm EEA stapler tends to have higher rates of EGD and MU.

Multiple brain injury criteria (BIC) are developed to quickly quantify brain injury risks after head impacts. These BIC originated from different head impact types (e.g. sports and car crashes) are widely used in risk evaluation. However, the accuracy of using the BIC on brain injury risk estimation across head impact types has not been evaluated. Physiologically, brain strain is often considered the key parameter of brain injury. To evaluate the BIC's risk estimation accuracy across five datasets comprising different head impact types, linear regression was used to model 95% maximum principal strain, 95% maximum principal strain at the corpus callosum and cumulative strain damage (15%) on 18 BIC. The results show significantly different relationships between BIC and brain strain across datasets, indicating the same BIC value may suggest different brain strain across head impact types. The accuracy of brain strain regression is generally decreasing if the BIC regression models are fitted on a dataset with a different type of head impact rather than on the dataset with the same type. Given this finding, this study raises concerns for applying BIC to estimate the brain injury risks for head impacts different from the head impacts on which the BIC was developed.

Efficient on-chip integration of single-photon emitters imposes a major bottleneck for applications of photonic integrated circuits in quantum technologies. Resonantly excited solid-state emitters are emerging as near-optimal quantum light sources, if not for the lack of scalability of current devices. Current integration approaches rely on cost-inefficient individual emitter placement in photonic integrated circuits, rendering applications impossible. A promising scalable platform is based on two-dimensional (2D) semiconductors. However, resonant excitation and single-photon emission of waveguide-coupled 2D emitters have proven to be elusive. Here, we show a scalable approach using a silicon nitride photonic waveguide to simultaneously strain-localize single-photon emitters from a tungsten diselenide (WSe 2 ) monolayer and to couple them into a waveguide mode. We demonstrate the guiding of single photons in the photonic circuit by measuring second-order autocorrelation of g (2) (0) = 0.150 ± 0.093 and perform on-chip resonant excitation, yielding a g (2) (0) = 0.377 ± 0.081. Our results are an important step to enable coherent control of quantum states and multiplexing of high-quality single photons in a scalable photonic quantum circuit., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Objective: Approximately 40% of the U.S. adult population are obese. An issue associated with this trend is proper seat belt fit for obese occupants. This study extends previous research, in which few individuals with high BMI (> 40 kg/m 2 ) were included, by examining the relationship between participant and belt factors on belt fit for drivers with Class I-III obesity., Methods: Posture and belt fit of 52 men and women with BMI from 31 to 59 kg/m 2 (median 38 kg/m 2 ) were measured in a laboratory vehicle mockup. Five seat belt configurations were achieved by manipulating the belt anchorage locations. Body and belt landmark locations were recorded using a three-dimensional coordinate measuring machine., Results: Higher BMI was associated with a lap belt position further forward and higher relative to the pelvis. On average, the lap belt was positioned an additional 32 mm forward and 13 mm above the ASIS with each increasing level of obesity classification. Sex had a small effect after accounting for BMI and stature. The mean fore-aft location of the lap belt was 24 mm more forward for men vs. women and 12 mm higher for women vs. men at the same stature and BMI. On average, women used 50 mm more belt webbing in the lap and 92 mm more in the shoulder vs. men., Conclusions: The results suggest that increasing levels of obesity class effectively introduces slack in the seat belt system by routing the belt further away from the skeleton. Because the belt is designed to engage the pelvis during a frontal crash, belt placements that are higher and further forward may increase injury risk by allowing excursions or submarining. Unique to this cohort, sex had an important effect on belt fit measures after taking into account stature and BMI. The participant and belt factors considered explained only about 40% of the variance in belt fit. The remaining variance may be due to preference or exogenous body shape effects. Further research is needed to assess methods for enhanced seat belt fit for people with obesity, including addressing sex differences in belt routing.

Background: Correlating patient outcomes with length of stay (LoS) is an important consideration in metabolic and bariatric surgery. At present, conflicting data exists regarding patient safety for ambulatory (AMB) metabolic and bariatric surgery., Objective: Outcomes for AMB-metabolic and bariatric surgery patients (LoS <1 d) undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) were compared with matched patients with LoS ≥1 day (non-AMB) using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) registry., Setting: MBSAQIP national database., Methods: The MBSAQIP registry was queried for patients undergoing SG or RYGB (2015-2017) and patients grouped as AMB/non-AMB. Exclusion criteria included LoS >4 days, age <18 or >75 years, revision surgery, gastric banding, body mass index <35 kg/m 2 , and day of surgery mortality. Variables were combined into major/minor complications and 30-day mortality. Analysis was performed using univariate and multivariate logistic regression and propensity matching., Results: After exclusions were applied 408,895 patients remained (9973 AMB). Overall, 111,279 patients underwent RYGB (1032 AMB) and 297,616 underwent SG (8941 AMB), with similar demographic characteristics and co-morbidities between groups. For AMB patients, there was no increase in 30-day mortality, reoperation, or readmission, and fewer drains were placed versus matched non-AMB patients. In AMB-SG patients more surgical site infections were reported versus non-AMB-SG, although AMB-SG patients had fewer intensive care unit admissions. For AMB-RYGB, no differences in complications were detected versus non-AMB-RYGB., Conclusion: Based on our analysis of the MBSAQIP database, patients undergoing laparoscopic RYGB or SG procedures can be safely discharged on the day of their procedure without increased incidence of mortality, reoperation, or readmission., (Published by Elsevier Inc.)

Background: The obesity rate for the Hispanic population is significantly higher than that of white, non-Hispanic people in the United States, yet Hispanic people undergo disproportionately fewer metabolic and bariatric surgery procedures. This study used the Metabolic Bariatric Surgery Accreditation and Quality Improvement Program data registry to examine potential differences in preoperative co-morbidities and postoperative outcomes in Hispanic adults undergoing sleeve gastrectomy or Roux-en-Y gastric bypass procedures in the United States., Objectives: To study the presence of the Hispanic paradox in metabolic and bariatric surgery utilizing the MBSAQIP registry., Setting: Academic Teaching Institution., Methods: Participant User Files from the Metabolic Bariatric Surgery Accreditation and Quality Improvement Program were reviewed for patients undergoing sleeve gastrectomy or Roux-en-Y gastric bypass (2015-2017). Patients were grouped by race (Hispanic versus all other races) and primary procedure performed. Variables for major and minor postoperative complications were combined. A univariate analysis was performed on unmatched and propensity-matched cohorts., Results: After applying exclusions, 53,353 (13.7%) Hispanic patients and 335,299 non-Hispanic patients remained. A univariate analysis demonstrated Hispanic patients had the lowest preoperative co-morbidity profile compared with all other races and decreased rates of major and minor postoperative complications. Using matched-cohort data, when complications were assessed and grouped as major/minor complications, rates of major and minor complications in Hispanic patients were lower in the Roux-en-Y gastric bypass group, despite Hispanic patients having higher leak rates. Similarly, there were no differences between Hispanic/non-Hispanic sleeve gastrectomy patients in overall major/minor complication rates despite Hispanic patients exhibiting higher venous thromboembolism and lower bleeding compared with non-Hispanic patients., Conclusion: Hispanic patients undergo disproportionately low rates of metabolic and bariatric surgery procedures and present with lower incidence of preoperative co-morbidities. Additionally, Hispanic patients have the same or decreased incidence of postoperative complications compared with non-Hispanic patients, thereby corroborating the Hispanic paradox., (Copyright © 2020 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Bariatric surgery is the most effective modality to treat obesity and obesity-related comorbidities. This study sought to utilize the MBASQIP® Data Registry to analyze the impact of age at time of surgery on outcomes following sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) procedures., Methods: The MBSAQIP® Data Registry for patients undergoing SG or RYGB procedures between 2015 and 2016 was reviewed. Patients were divided into 4 age groups [18-44; 45-54; 55-64; > 65 years]. Minimal exclusions for revisional and/or emergency surgery were selected and combination variables created to classify complications as major or minor. A comorbidity index was constructed to include diabetes, gastroesophageal reflux disease (GERD), obstructive sleep apnea (OSA), and prior cardiac surgery. Univariate and multivariate logistic regression analyses were performed to compare age stratifications to the young adult (18-45 years) cohort., Results: Of 301,605 cases, 279,419 cases (71.2% SG) remained after applying exclusion criteria (79.2% female, mean BMI 45.5 ± 8.1 kg/m 2 , 8.9% insulin-dependent diabetics). Mean age was 44.7 ± 12.0 years (51.3% 18-44 years; 26.9% 45-54 years; 16.3% 55-64 years; 5.5% > 65 years). A univariate analysis demonstrated preoperative differences of lower BMI with increasing age concomitant with increasing frequency of RYGB and a higher comorbidity index (p < 0.0001 vs. 18-45 years). At age > 45 years, major complications and 30-day mortality increased independent of procedure type (p < 0.0001). A multivariate analysis controlling for comorbidity indices demonstrated increasing age (> 45 years) increased risk for major complications and mortality., Conclusion: Overall, bariatric surgery (SG or RYGB) remains a low mortality risk procedure for all age groups. However, all age group classifications > 45 years had higher incidence of major complications and mortality compared to patients 18-45 years (despite older individuals having lower preoperative BMI) indicating delaying surgery is detrimental.

Background: Male patients undergoing bariatric surgery have (historically) been considered higher risk than females. The aim of this study was to examine the disparity between genders undergoing laparoscopic sleeve gastrectomy (SG) and laparoscopic Roux-en-Y gastric bypass (RYGB) procedures and assess gender as an independent risk factor., Methods: The MBSAQIP® Data Registry Participant User Files for 2015-2017 was reviewed for patients having primary SG and RYGB. Patients were divided into groups based on gender and procedure. Variables for major complications were grouped together, including but not limited to PE, stroke, and MI. Univariate and propensity matching analyses were performed., Results: Of 429,664 cases, 20.58% were male. Univariate analysis demonstrated males were older (46.48 ± 11.96 vs. 43.71 ± 11.89 years, p < 0.0001), had higher BMI (46.58 ± 8.46 vs. 45.05 ± 7.75 kg/m 2 , p < 0.0001), and had higher incidence of comorbidities. Males had higher rates of major complications (1.72 vs. 1.05%; p < 0.0001) and 30-day mortality (0.18 vs. 0.07%, p < 0.0001). Significance was maintained after subgroup analysis of SG and RYGB. Propensity matched analysis demonstrated male gender was an independent risk factor for RYGB and SG, major complications [2.21 vs. 1.7%, p < 0.0001 (RYGB), 1.12 vs. 0.89%, p < 0.0001 (SG)], and mortality [0.23 vs. 0.12%, p < 0.0001 (RYGB), 0.10 vs. 0.05%; p < 0.0001 (SG)]., Conclusion: Males continue to represent a disproportionately small percentage of bariatric surgery patients despite having no difference in obesity rates compared to females. Male gender is an independent risk factor for major post-operative complications and 30-day mortality, even after controlling for comorbidities.

Given the worldwide adverse impact of traumatic brain injury (TBI) on the human population, its diagnosis and prediction are of utmost importance. Historically, many studies have focused on associating head kinematics to brain injury risk. Recently, there has been a push toward using computationally expensive finite element (FE) models of the brain to create tissue deformation metrics of brain injury. Here, we develop a new brain injury metric, the brain angle metric (BAM), based on the dynamics of a 3 degree-of-freedom lumped parameter brain model. The brain model is built based on the measured natural frequencies of an FE brain model simulated with live human impact data. We show that it can be used to rapidly estimate peak brain strains experienced during head rotational accelerations that cause mild TBI. In our data set, the simplified model correlates with peak principal FE strain ( R 2  = 0.82). Further, coronal and axial brain model displacement correlated with fiber-oriented peak strain in the corpus callosum ( R 2  = 0.77). Our proposed injury metric BAM uses the maximum angle predicted by our brain model and is compared against a number of existing rotational and translational kinematic injury metrics on a data set of head kinematics from 27 clinically diagnosed injuries and 887 non-injuries. We found that BAM performed comparably to peak angular acceleration, translational acceleration, and angular velocity in classifying injury and non-injury events. Metrics that separated time traces into their directional components had improved model deviance compare with those that combined components into a single time trace magnitude. Our brain model can be used in future work to rapidly approximate the peak strain resulting from mild to moderate head impacts and to quickly assess brain injury risk.

A 65-year-old man with dysphagia underwent placement of a percutaneous endoscopic gastrostomy tube. He was cared for at a nursing facility where the tube became dislodged and was replaced with similar size Foley catheter. Patient was brought to the hospital with dislodged feeding Foley but none was found at the bedside. Diagnostic workup revealed antegrade migration of the catheter into the small bowel. Push enteroscopy was unsuccessful in retrieving the catheter because it was too far distal. Patient was observed for a total of 7 days. Due to lack of progress with conservative measures, a colonoscopy was performed to extract the catheter, thus avoiding the need for more invasive surgical measures. If a Foley catheter is used as a gastrostomy tube, it should be replaced with a dedicated feeding tube as quickly as possible and should always be affixed to the skin to prevent antegrade migration and associated complications., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.)