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IntroductionReal-time physiological episode (PE) detection and management in aircrew operating high-performance aircraft (HPA) is crucial for the US Military. This paper addresses the unique challenges posed by high acceleration (G-force) in HPA aircrew and explores the potential of a novel wearable functional near-infrared spectroscopy (fNIRS) system, named NIRSense Aerie, to continuously monitor cerebral oxygenation during high G-force exposure.MethodsThe NIRSense Aerie system is a flight-optimized, wearable fNIRS device designed to monitor tissue oxygenation 13–20 mm below the skin's surface. The system includes an optical frontend adhered to the forehead, an electronics module behind the earcup of aircrew helmets, and a custom adhesive for secure attachment. The fNIRS optical layout incorporates near-distance, middle-distance, and far-distance infrared emitters, a photodetector, and an accelerometer for motion measurements. Data processing involves the modified Beer-Lambert law for computing relative chromophore concentration changes. A human evaluation of the NIRSense Aerie was conducted on six subjects exposed to G-forces up to +9 Gz in an Aerospace Environmental Protection Laboratory centrifuge. fNIRS data, pulse oximetry, and electrocardiography (HR) were collected to analyze cerebral and superficial tissue oxygenation kinetics during G-loading and recovery.ResultsThe NIRSense Aerie successfully captured cerebral deoxygenation responses during high G-force exposure, demonstrating its potential for continuous monitoring in challenging operational environments. Pulse oximetry was compromised during G-loading, emphasizing the system's advantage in uninterrupted cerebrovascular monitoring. Significant changes in oxygenation metrics were observed across G-loading levels, with distinct responses in Deoxy-Hb and Oxy-Hb concentrations. HR increased during G-loading, reflecting physiological stress and the anti-G straining maneuver.DiscussionThe NIRSense Aerie shows promise for real-time monitoring of aircrew physiological responses during high G-force exposure. Despite challenges, the system provides valuable insights into cerebral oxygenation kinetics. Future developments aim for miniaturization and optimization for enhanced aircrew comfort and wearability. This technology has potential for improving anti-G straining maneuver learning and retention through real-time cerebral oxygenation feedback during centrifuge training.

Abstract Background Natalizumab and fingolimod are used as high-efficacy treatments in relapsing–remitting multiple sclerosis. Several observational studies comparing these two drugs have shown variable results, using different methods to control treatment indication bias and manage censoring. The objective of this empirical study was to elucidate the impact of methods of causal inference on the results of comparative effectiveness studies. Methods Data from three observational multiple sclerosis registries (MSBase, the Danish MS Registry and French OFSEP registry) were combined. Four clinical outcomes were studied. Propensity scores were used to match or weigh the compared groups, allowing for estimating average treatment effect for treated or average treatment effect for the entire population. Analyses were conducted both in intention-to-treat and per-protocol frameworks. The impact of the positivity assumption was also assessed. Results Overall, 5,148 relapsing–remitting multiple sclerosis patients were included. In this well-powered sample, the 95% confidence intervals of the estimates overlapped widely. Propensity scores weighting and propensity scores matching procedures led to consistent results. Some differences were observed between average treatment effect for the entire population and average treatment effect for treated estimates. Intention-to-treat analyses were more conservative than per-protocol analyses. The most pronounced irregularities in outcomes and propensity scores were introduced by violation of the positivity assumption. Conclusions This applied study elucidates the influence of methodological decisions on the results of comparative effectiveness studies of treatments for multiple sclerosis. According to our results, there are no material differences between conclusions obtained with propensity scores matching or propensity scores weighting given that a study is sufficiently powered, models are correctly specified and positivity assumption is fulfilled.

A parallel series of general chemistry courses for Life Science Majors was created in an effort to support students and improve general chemistry outcomes. We created a two-quarter enhanced general chemistry course series that is not remedial, but instead implements several evidence-based teaching practices including Process Oriented Guided Inquiry Learning (POGIL), Peer-Led Team Learning (PLTL), and the Learning Assistant (LA) model. We found that students who took enhanced general chemistry had higher persistence to the subsequent first organic chemistry course, and performed equally well in the organic course compared to their peers who took standard general chemistry. Students in the first enhanced general chemistry course also reported significantly higher belonging, although we were unable to determine if increased belonging was associated with the increased persistence to organic chemistry. Rather we found that the positive association between taking the enhanced general chemistry course and persistence to organic chemistry was mediated by higher grades received in the enhanced general chemistry course. Our findings highlight the responsibility we have as educators to carefully consider the pedagogical practices we use, in addition to how we assign student grades.

Introduction: The high diagnostic accuracy of plasma metanephrines (PMets) in the diagnosis of Phaeochromocytoma/Paraganglioma (PPGL) is well established. Considerable controversy exists regarding optimum sampling conditions for PMets. The use of reference intervals that do not compromise diagnostic sensitivity is recommended. However, the optimum rest period prior to sampling has yet to be clearly established. The aim of this study was to evaluate PMets concentrations in paired blood samples collected following 30 and 40 min seated-rest prior to sampling, in patients in whom it was clinically reasonable to suspect that PPGL may be present. Design and Methods: A retrospective cross-sectional study design was used. PMets results from paired blood samples collected after 30 and 40 min seated-rest between January 2009 and June 2015 were recorded. Results were interpreted using reference intervals established in subjects seated and supine. Results: A total of 410 patient results were eligible for analysis. There was no statistical difference between plasma normetanephrine (NMN) or metanephrine (MN) concentrations in samples collected following 30 and 40 min seated-rest in subjects with PPGL (n=11), post-resection of PPGL (n=20) or in whom PPGL was excluded (n=379). Using reference intervals established in the seated position, diagnostic sensitivity was 100% at 30 min and 90.9% at 40 min. Diagnostic specificity was approximately 95% at both time points. When supine reference intervals were used, diagnostic sensitivity was 100% and diagnostic specificity was reduced by ≈22% at both time points. Conclusion: Based on these data, we recommend at most 30 min continuous rest prior to sampling for PMets measurement. Keywords: Plasma metanephrine, Plasma normetanephrine, Phaeochromocytoma, Diagnostic sensitivity, Diagnostic specificity

During COVID-19 remote instruction, instructors were tasked with providing students with authentic laboratory experiences in an out-of-classroom environment. One solution developed for our introductory general chemistry laboratory involved students critiquing readily available technique videos to distinguish between correct and incorrect laboratory technique. After returning to in-person labs in Fall 2021, we incorporated this assessment into the pre-lab assignments in an effort to reduce the cognitive load of learning a new technique. Here we explore whether this critical-review exercise translates into improved technique as measured by precision and accuracy when using a 10 mL volumetric pipet. Additionally, we consider the impact of the pre-lab assignment given the involvement level of the TA, as some TAs are more willing to provide feedback on student technique during the lab period. We found that while students self-report the exercise as useful towards their learning, there are no significant changes in performance for most students. We did, however, find a reduction in the overall outliers and saw improvements when additional feedback (through a TA) was provided as well. These findings indicate that the exercise may be most useful for students who make large errors and who receive little individualized feedback.

With the support of the US National Science Foundation (NSF) and on behalf of the international seismological community, IRIS developed a Data Management Center (DMC; Ahern, 2003) that has for decades acted as a primary resource for seismic networks wishing to make their data broadly available, as well as a significant point of access for researchers and monitoring agencies worldwide that wish to access high quality data for a variety of purposes. Recently IRIS has taken significant new steps to improve the quality of and access to the services of the IRIS DMC. This paper highlights some of the current new efforts being undertaken by IRIS. The primary topics include (1) steps to improve reliability and consistency of access to IRIS data resources, (2) a comprehensive new approach to assessing the quality of seismological and other data, (3) working with international partners to federate seismological data access services, and finally (4) extensions of the federated concept to extend data access to data from other geoscience domains.

We report here a successful adaptation of lab videos used during remote instruction to a kinetics experiment reported in this Journal in 2007. In the in-person lab, students now record their rate data on their cell phone cameras and then collect their data from the videos for their postlab reports; previously, they acquired the data in real time from the spectrophotometer reading and a stopwatch. We have found that increasing the concentration of the bleach, which speeds up the rate faster than data can be directly recorded in real time (1) does not affect the reaction order and (2) decreases lab time.