Commercial off-the-shelf (COTS) explosive trace detectors (ETDs) have become an integral part of security practices aimed at protecting the public, transportation, and facilities. Despite their widespread deployment, quality control procedures that can evaluate day-to-day instrument performance or differences among units of the same manufacture are in need for development. In this work, we describe the preparation of test materials (TMs) using inkjet printing that have fixed dosing levels of two explosives; 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and pentaerythritol tetranitrate (PETN). The uncertainty in the mass of dispensed solute is 0.8% (nominal 1 ng RDX and 5 ng or 20 ng PETN depending on ETD). TMs are stable under storage for at least 20 days at temperatures consistent with indoor and outdoor environments, and can be used by field personnel at deployed locations. Inkjet printing is shown to provide the necessary control over the spatial distribution of analyte on the substrate, thus limiting the variability in the signal response due to the sample. Measurements of signal intensities for two COTS ETDs were obtained from TMs over multi-year time spans and for multiple units of each ETD. Reproducibility in the signal response is shown to be between 6% and 15% RSD, or approximately double the within-day variability. The large datasets allow for the first time modeling of signal intensities with respect to normal distributions, which support the use of standard 3-sigma control practices.

Introduction The purpose of this study was to compare the rotational blunt impact performance of an anthropomorphic test device (ATD: male 50% Hybrid III head and neck) headform donning an Advanced Combat Helmet (ACH) between conditions in which the coefficient of static friction (μs) at the head-to-helmet pad interface varied. Materials and Methods Two ACHs (size large) were used in this study and friction was varied using polytetrafluoroethylene (PTFE), human hair, skullcap, and the native vinyl skin of the ATD. A condition in which hook and loop material adhered the headform to the liner system was also tested, resulting in a total of five conditions: PTFE, Human Hair, Skullcap, Vinyl, and Hook. Blunt impact tests with each helmet in each of the five conditions were conducted on a pneumatic linear impactor at 4.3 m/s. The ATD donning the ACH was impacted in seven locations (Crown, Front, Rear, Left Side, Right Side, Left Nape, and Right Nape). The peak resultant angular acceleration (PAA), velocity (PAV), and the Diffuse Axonal Multi-Axis, General Evaluation (DAMAGE) metric were compared between conditions. Results No pairwise differences were observed between conditions for PAA. A positive correlation was observed between mean μs and PAA at the Front (τ = 0.28; P = .044) and Rear (τ = 0.31; P = .024) impact locations. The Hook condition had a mean PAV value that was often less than the other conditions (P ≤ .024). A positive correlation was observed between mean μs and PAV at the Front (τ = 0.32; P = .019) and Right Side (τ = 0.57; P < .001) locations. The Hook condition tended to have the lowest DAMAGE value compared to the other conditions (P ≤ .032). A positive correlation was observed between the mean μs and DAMAGE at the Rear (τ = 0.60; P < .001) location. A negative correlation was observed at the Left Side (τ = -0.28; P = .040), Right Side (τ = -0.58; P < .001) and Left Nape (τ = -0.56; P < .001) locations. Conclusions The results of this study indicate that at some impact locations kinematic responses can vary as a function of the friction at the head-to-helmet pad interface. However, a reduction in the coupling of the head-helmet pad interface did not consistently reduce head angular kinematics or measures of brain strain across impact locations. Thus, for the ACH during collision-type impacts, impact location as opposed to μs seems to have a greater influence on head kinematics and rotational-based measures of brain strain.

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Category: Other; Ankle; Hindfoot; Lesser Toes; Midfoot/Forefoot Introduction/Purpose: The automation and integration of patient reported outcomes (PROs) into standard of care practice and electronic health systems is becoming increasingly viable. While often collected as a quality assurance measure for a practice and surgical decision-making, PROs are also valuable to assess the relative treatment outcomes. In order for physicians to gain the most insight from PROs, more baseline outcomes are needed to serve as a benchmark of anticipated patient improvement following surgical interventions. The goal of this study is to evaluate differences in patient improvement among validated physical and mental health PROs in a foot and ankle surgery practice. Methods: Consecutive patients undergoing foot and ankle surgery were enrolled into the U-COSMOS pathway. All PROs are automatically distributed and tracked through a secure, HIPAA-compliant, online PRO data capture tool. All patients are invited to complete the PROMIS Physical Function (PF) Computer Adaptive Test (CAT), PROMIS Pain Interference CAT (PI), Foot and Ankle Single Assessment Numeric Evaluation (SANE), PROMIS Global Physical Health (GPH), PROMIS Global Mental Health (GMH), PROMIS Depression, and a brief resiliency scale (BRS). PROs are collected pre-operatively, and post-operatively at 3- months, 6-months, 12-months, and 24-months. In this study, differences between pre- and post-operative scores for each PRO are evaluated using an unpaired Mann-Whitney U Test. Results: To date, 3154 patients have been enrolled into the U-COSMOS foot and ankle surgery pathway. Overall survey compliance was 77%. A significant improvement was seen in PF, PI, SANE, and GPH at 6-months, 12-months, and 24-months (p < 0.0001, see Table 1). There was no significant improvement in PF or GPH at the 3-month mark, supporting reduction of pain interference may be observed before return of physical function. All PROs measuring changes in mental health or resilience (Depression, GMH, BRS) did not significantly change at any post-operative visit relative to baseline. We found a mild positive correlation between BRS and improved 12-month PF and PI outcomes and a mild inverse correlation between pre-operative depression and 12-month PI and PF scores. Conclusion: Our data suggests that foot and ankle surgery leads to significant improvement in physical outcomes such as function or pain interference, but mental health and resilience outcomes remain somewhat unchanged throughout treatment on average. Within physical outcomes, we also find significant improvement in pain interference precedes functional and general measures. Early findings from the U-COSMOS outcomes pathway demonstrates greater overall improvement in physical health PROs, and a sustained improvement up to 24 months post-op. Future investigation of outcomes specific to procedures and conditions within the U-COSMOS pathway will help elucidate anticipated variation from general trends.