Young stellar objects (YSOs) are protostars that exhibit bipolar outflows fed by accretion disks. Theories of the transition between disk and outflow often involve a complex magnetic field structure thought to be created by the disk coiling field lines at the jet base; however, due to limited resolution, these theories cannot be confirmed with observation and thus may benefit from laboratory astrophysics studies. We create a dynamically similar laboratory system by driving a $\sim$1 MA current pulse with a 200 ns rise through a $\approx$2 mm-tall Al cylindrical wire array mounted to a three-dimensional (3-D)-printed, stainless steel scaffolding. This system creates a plasma that converges on the centre axis and ejects cm-scale bipolar outflows. Depending on the chosen 3-D-printed load path, the system may be designed to push the ablated plasma flow radially inwards or off-axis to make rotation. In this paper, we present results from the simplest iteration of the load which generates radially converging streams that launch non-rotating jets. The temperature, velocity and density of the radial inflows and axial outflows are characterized using interferometry, gated optical and ultraviolet imaging, and Thomson scattering diagnostics. We show that experimental measurements of the Reynolds number and sonic Mach number in three different stages of the experiment scale favourably to the observed properties of YSO jets with $Re\sim 10^5\unicode{x2013}10^9$ and $M\sim 1\unicode{x2013}10$, while our magnetic Reynolds number of $Re_M\sim 1\unicode{x2013}15$ indicates that the magnetic field diffuses out of our plasma over multiple hydrodynamical time scales. We compare our results with 3-D numerical simulations in the PERSEUS extended magnetohydrodynamics code.

In the absence of a treaty protocol or verification regime, the Biological and Toxin Weapons Convention (BWC) instituted confidence-building measures (CBMs) as a mechanism to increase confidence in compliance by enhancing transparency and mitigating ambiguities regarding states parties’ biological activities. While a promising tool to support treaty compliance, low participation, concerns regarding the completeness and accuracy of CBM submissions, a dearth of analysis, and restricted access to many submissions have limited CBMs’ value. Through interviews with 53 international experts—38 from BWC delegations and 15 independent experts—we identified concrete opportunities to increase CBMs’ value while mitigating the burden on states parties. This study supports states parties’ efforts in the BWC Working Group on the Strengthening of the Convention, as part of a series of research on BWC assurance that aims to characterize challenges around BWC verification and increase certainty in BWC compliance.

Background: Acute respiratory infections (ARIs) are a key target to improve antibiotic use in the outpatient setting. The Core Elements of Outpatient Antibiotic Stewardship provide a framework for improving antibiotic use, but data on safety and effectiveness of interventions to improve antibiotic use are limited. We report the impact of Core Elements implementation within Veterans’ Healthcare Administration clinics on antibiotic prescribing and patient outcomes. Methods: The intervention targeting treatment of uncomplicated ARIs (sinusitis, pharyngitis, bronchitis, and viral upper respiratory infections [URIs]) in emergency department and primary care settings was initiated within 10 sites between September 2017 and January 2018. The intervention was developed using the Core Elements and included local site champions, audit-and-feedback with peer comparison, and academic detailing. We evaluated the following outcomes: per-visit antibiotic prescribing rates overall and by diagnosis; appropriateness of treatment; 30-day ARI revisits; 30-day infectious complications (eg,, pneumonia,); 30-day adverse medication effects; 90-day Clostridium difficile infection (CDI); and 30-day hospitalizations. Multilevel logistic regression was used to calculate rate ratios (RR) with 95% CI for each outcome in the postintervention period (12 months) compared to the preintervention period (39–42 months). Results: There were 14,020 uncomplicated ARI visits before the intervention and 4,866 uncomplicated ARI visits after the intervention. The proportions of uncomplicated ARI visits with antibiotics prescribed were 59.17% before the intervention versus 44.34% after the intervention. A trend in reduced antibiotic prescribing for ARIs throughout the entire (before and after) observation period was evident (0.92; 95% CI, 0.90–0.94); however, a significant reduction in antibiotic prescribing after the intervention was identified (0.74; 95% CI, 0.59–0.93). Per-visit antibiotic prescribing rates decreased significantly for bronchitis and URI (0.54; 95% CI, 0.44–0.65), pharyngitis (0.76; 95% CI, 0.67–0.86), and sinusitis (0.92; 95% CI, 0.85–1.0). Appropriate therapy for pharyngitis increased (1.43; 95% CI, 1.21–1.68), but appropriate therapy for sinusitis remained unchanged (0.92; 95% CI, 0.85–1.0) after the intervention. Complications associated with antibiotic undertreatment were not different after the intervention: ARI-related revisit rates (1.01; 95% CI, 0.98–1.05) and infectious complications (1.01; 95% CI, 0.79–1.28). A potential benefit of improved antibiotic use included a reduction in visits for adverse medication effects (0.82; 95% CI, 0.72–0.94). Furthermore, 90-day CDI events were too sparse to model: preintervention incidence was 0.08% and postintervention incidence was 0.06%. Additionally, 30-day hospitalizations were significantly lower in the postintervention period (0.79; 95% CI, 0.72–0.87). Conclusions: Implementation of the Core Elements was safe and effective and was associated with reduced antibiotic prescribing rates for uncomplicated ARIs, improvements in diagnosis-specific appropriate therapy, visits for adverse antibiotic effects, and 30-day hospitalization rates. No adverse events were noted in ARI-related revisit rates or infectious complications. CDI rates were low and unchanged.

Funding: None

Disclosures: None