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The contents of this publication are the sole responsibility of the authors and do not necessarily reflect the views, opinions ir policies of the Henry M.Jackson Foundation for the Advancement of Military Medicine, Inc. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government. Results from an approach to simulate muzzle blast shows very good agreement with data. The simulations provide full 3D blast environment (including multiple peaks) from burning propellant. The results are used to mitigate blast exposure by adjusting body position and orientation (where possible) while still conducting training. The longer-term goal is to address concerns about negative impacts on brain health. Acknowledgements Simulating Blast Exposure on Personnel During Combat Training While Operating: Mortars, Howitzers, and .50 Caliber Guns The simulations were initialized with a uniform high-pressure volume of burned propellant. The velocity of the gas in the tube varied linearly from zero at the base of the tube to the muzzle velocity at the end of the tube. This represents the velocity distribution just as the projectile leaves the muzzle. The specific internal energy was uniformly distributed within the tube. The LSZK equation of state was used for the burned propellant, and the Doan Nickel equation of state was used for the air. The simulations did not include the projectiles since the primary focus is air blast exposure on the personnel. The simulated peak overpressure contours show the blast exposure on and around the personnel for each weapon system. Understanding blast exposure on personnel during training and combat is important as it may potentially negatively impact brain health in the short- and long-term. Blast overpressure data was collected on and around service members operating weapons with muzzle brakes to better understand the exposures experienced by the operators. These measured overpressures were then compared wi, RITM0039084, Understanding blast exposure on personnel during training and combat is important as it may potentially negatively impact brain health in the short- and long-term. Blast overpressure data was collected on and around service members operating weapons with muzzle brakes to better understand the exposures experienced by the operators. These measured overpressures were then compared with 3D simulations. Data collected from Blast Gauges can quantify the magnitude of blast exposure on an individual at specific locations. High-fidelity simulations provide contours of blast magnitude all around the weapon systems and operators

The general agreement (~20%) between measurements with the BG (using procedure) and the pencil probe demonstrates the viability of the B3 gauge to measure blast overpressure. One could utilize these devices and the proposed procedure to estimate incident overpressure around weapons systems without a data acquisition system, wires, and laboratory-grade sensors. The results could also provide information on the blast environment experienced by personnel during training, which could be used to develop safety guidelines to mitigate blast exposure by increasing stand off distance and adjusting body position around a weapon system or blast source. Acknowledgements Measuring Air Blast Overpressure During Military Training Using BlackBox Biometrics Blast Gauges Mounted on Stakes and Comparison with Pencil Probe Data The B3 gauge has a perforated dome to protect the sensor from debris and particulates. A stake instrumented with three face on BGs, a pencil probe, and one rotated BG is shown. Photos of the weapon systems/blast source from training are shown. The figures below show examples of the raw BG data compared to the pencil probe data. These plots show the overall agreement between the BG data and pencil probes over the whole waveform, along with the BG “spike” at the first peak. When the procedure is used on the BG data, the estimated incident overpressures are in good agreement with corresponding pencil probe measurements, differing in a range of -21.5% to 2.2%, as seen in the table. Understanding the blast environment on and around service members in combat training is important as researchers work to correlate blast exposure with brain health. Both incident peak overpressure and impulse are used to correlate blast exposure with risk of injury (e.g. lung). However, current methods of blast overpressure measurement can be cumbersome in the training environment. Body-mounted sensors can record data during training. We present a comparison of the laboratory-grade PCB pe, RITM0039080, Understanding the blast environment on and around service members in combat training is important as researchers work to correlate blast exposure with brain health. Both incident peak overpressure and impulse are used to correlate blast exposure with risk of injury (e.g. lung). However, current methods of blast overpressure measurement can be cumbersome in the training environment. Body-mounted sensors can record data during training. We present a comparison of the laboratory-grade PCB pencil probe overpressure sensor with the wireless, more portable BlackBox Biometrics (B3) Blast Gauge System mounted on stakes. Quantifying the differences between these two sensors will allow for more convenient data collection as researchers continue to investigate the correlation between low level blast exposure and effects on the brain.

The Effects of Gauge Mounting on Blast Overpressure Measurements Using Blackbox Biometrics (B3) Blast Gauges Background Results Methods Disclaimers Acknowledgements References The opinions and assertions expressed herein are those of the author(s) and do not necessarily reflect the official policy or position of the Uniformed Services University or the Department of Defense. The contents of this publication are the sole responsibility of the author(s) and do not necessarily reflect the views, opinions or policies of The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government. This work was funded by the Uniformed Services University: HU0001-19-2-0049 Wiri, S., Needham, C., Longwell, J., Gonzales, A., Watry, C., Graves, W., Massow, T., Whitty, J., Reid, J., Leonessa, F., Duckworth, J.: The Effects of Gauge Mounting on Blast Overpressure Measurements Using Blackbox Biometrics (B3) Blast Gauges. Shock Waves (submitted). Understanding blast exposure is important for protecting our service members. In order to accurately quantify blast exposure events, understanding the physics of the blast wave as it interacts with recording hardware and mounting is necessary. Through the Combat and Training Queryable Exposure/Event Repository (CONQUER) program, blast overpressure and impulse data were collected from blast gauges on different static mount configurations. The data show that the BG (either facing or rotated 90 degrees) records a “spike” in the overpressure in excess of the incident overpressure value at shock arrival. This signal could be caused by the partial stagnation of the incoming wave by the protective shield over the pressure sensing surface and the body of the sensor. The magnitude of this shock reflection is a function of the gauge orientation relative to the blast source and the shock strength. After the initial spike, the BG data i, RITM0040591, Understanding blast exposure is important for protecting our service members. In order to accurately quantify blast exposure events, understanding the physics of the blast wave as it interacts with recording hardware and mounting is necessary. Through the Combat and Training Queryable Exposure/Event Repository (CONQUER) program, blast overpressure and impulse data were collected from blast gauges on different static mount configurations.

Septic shock carries substantial morbidity and mortality. The failure of many promising therapies during late-phase clinical trials prompted calls for alternative trial designs. We describe an innovative trial evaluating selepressin, a novel selective vasopressin V receptor agonist, for adults with septic shock. SEPSIS-ACT (Selepressin Evaluation Programme for Sepsis-induced Shock-Adaptive Clinical Trial) is a blinded, randomized, placebo-controlled, two-part, adaptive phase 2b/3 trial, evaluating up to four selepressin dosing strategies. The primary outcome is pressor- and ventilator-free days, with a value of zero assigned for death within 30 days. We calculate Bayesian probabilities of final trial success to guide interim decision-making. Part 1 (dose-finding) has an adaptive sample size based on response-adaptive randomization and prespecified rules to determine stopping for futility or selection of the best dosing regimen for Part 2. Part 2 (confirmation) randomizes a minimum of 1,000 patients equally to the selected dosing regimen or placebo. The final estimate of treatment effect compares all selepressin-treated patients with all placebo-treated patients. The sample size of 1,800 provides 91% power to detect an increase of 1.5 pressor- and ventilator-free days with a reduction in mortality of 1.5%. The trial received a Special Protocol Assessment agreement from the U.S. Food and Drug Administration Center for Drug Evaluation and Research and is underway in Europe and the United States. SEPSIS-ACT is an innovative trial that addresses both optimal dose and confirmation of benefit, accelerating the evaluation of selepressin while mitigating risks to patients and sponsor through use of response-adaptive randomization, a novel registration endpoint, prespecified futility stopping rules, and a large sample size. Clinical Trial registered with www.clinicaltrials.gov (NCT02508649).

Septic shock carries substantial morbidity and mortality. The failure of many promising therapies during late-phase clinical trials prompted calls for alternative trial designs. We describe an innovative trial evaluating selepressin, a novel selective vasopressin V1a receptor agonist, for adults with septic shock. SEPSIS-ACT (Selepressin Evaluation Programme for Sepsis-induced Shock-Adaptive Clinical Trial) is a blinded, randomized, placebo-controlled, two-part, adaptive phase 2b/3 trial, evaluating up to four selepressin dosing strategies. The primary outcome is pressor- and ventilator-free days, with a value of zero assigned for death within 30 days. We calculate Bayesian probabilities of final trial success to guide interim decision-making. Part 1 (dose-finding) has an adaptive sample size based on response-adaptive randomization and prespecified rules to determine stopping for futility or selection of the best dosing regimen for Part 2. Part 2 (confirmation) randomizes a minimum of 1,000 patients equally to the selected dosing regimen or placebo. The final estimate of treatment effect compares all selepressin-treated patients with all placebo-treated patients. The sample size of 1,800 provides 91% power to detect an increase of 1.5 pressor- and ventilator-free days with a reduction in mortality of 1.5%. The trial received a Special Protocol Assessment agreement from the U.S. Food and Drug Administration Center for Drug Evaluation and Research and is underway in Europe and the United States. SEPSIS-ACT is an innovative trial that addresses both optimal dose and confirmation of benefit, accelerating the evaluation of selepressin while mitigating risks to patients and sponsor through use of response-adaptive randomization, a novel registration endpoint, prespecified futility stopping rules, and a large sample size. Clinical Trial registered with www.clinicaltrials.gov (NCT02508649).