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A method is described for choosing experimental parameters in studies of high-energy-density (HED) physics relevant to fusion energy, as well as other applications. An important HED issue for magneto-inertial fusion (MIF) is the interaction of metal pusher materials with megagauss (MG) magnetic fields during liner compression of magnetic flux and fusion fuel. The experimental approach described here is to study a stationary conductor when a pulsed current generates MG fields at the surface, instead of studying the inner surface of a moving liner. This places less demand upon the pulsed power system, and significantly improves diagnostic access. Thus the deceptively simple geometry chosen for this work is that of a z pinch composed of a metal cylinder carrying large current. Consideration of well known stability issues for the z pinch shows that for given peak current and rise time from a particular power supply, there is a minimum radius and thus maximum B field that can be created without disruption of the conductor before peak current. The reasons are reviewed why MG levels of magnetic field, as required for MIF, result in high temperatures and plasma formation at the surface of the metal in response to Ohmic heating. The distinction is noted between the liner regime obtained with cylindrical rods, which have a skin depth small compared to the conductor radius, and the exploding thin-wire regime, which has skin depth larger than the wire radius. A means of diagnostic development is described using a small facility (DPM15) built at the University of Nevada, Reno. It is argued that surface plasma temperature measurements in the 10-eV range are feasible based on the intensity of visible light emission.

At Los Alamos, we investigate solid density materials under extreme conditions of high pressure or strain. To further these studies, we develop pulsed power techniques for driving high energy imploding liners. We have developed the Ranchero explosive-driven magnetic flux compression generator (FCG) system to perform such experiments at very high energy, in remote locations. Our first charter is to support the development of the Atlas capacitor bank [1] which, when completed in 2001, will deliver up to 30 MA to hydrodynamic liners. The basic unit of the Ranchero system is a 1.4 m long coaxial FCG that is simultaneously initiated along its axis and has an armature expansion ratio of 2:1. We performed initial system tests using 43 cm long [2,3] coaxial modules and are finalizing the design and development of our 1.4 m detonation system. This development, which met with unexpected difficulties, is the subject of another paper in this conference [4]. The 43cm module combined with the 2.4 MJ capacitor bank at our high explosive pulsed power facility has the capability of delivering ~40 MA to a load of ~5 nH. Coupled with a fuse opening switch (FOS), the system will generate a good approximation of Atlas waveforms with 5 nH in the load and transmission lines. This allows us to begin preliminary Atlas related tests before the 1.4 m module is completed. Herein is described our efforts to develop the capability and the design of our first imploding liner experiment.

Ranchero is an explosively driven magnetic flux-compression generator that has been developed over the last four years as a versatile power source for high energy density physics experiments. It is coaxial and comprises a 15 cm diameter armature and a 30 cm diameter stator, each made of aluminum. The length may be varied to suit the demands of each experiment. Thus far, lengths of 0.43 m and 1.4 m have been used. The armature is filled and driven by a high-performance cast explosive, and the ultimate performance of the device is limited by the smoothness of the armature expansion. The armature explosive is initiated on axis by PETN hemispheres spaced at intervals of between 18 mm and 24.5 mm. Each is simultaneously detonated by a slapper detonator system. Armature expansion calculations predicted ripples less than 0.2 mm, which was confirmed in early experiments. Yet, ripples approaching tens of millimeters were observed in some more recent experiments. We will discuss the possible origins of these large ripples and the methods we have used to correct them.

Experimental data which considerably complements earlier results [1] is given for the initial perturbation growth of liners made of high-purity soft aluminum (A995, 99.995% Al) and high-strength aluminum alloys with major magnesium (AMg6) or zinc (B95) additives. Preliminary data analysis and comparison with VNIIEF and LANL numerical simulation allows us to revise parameter estimations of dynamic strength and conductivity of the materials used for designing magnetically driven liners.

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation 1 , 2 . Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid 1 – 3 . A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation 1 . NASA’s Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission’s target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft 4 . Although past missions have utilized impactors to investigate the properties of small bodies 5 , 6 , those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft’s autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos 7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary. The impact of the DART spacecraft on the asteroid Dimorphos is reported and reconstructed, demonstrating that kinetic impactor technology is a viable technique to potentially defend Earth from asteroids.

Background Prior studies in critically ill patients suggest the supra-physiologic chloride concentration of 0.9% (“normal”) saline may be associated with higher risk of renal failure and death compared to physiologically balanced crystalloids. However, the comparative effects of 0.9% saline and balanced fluids are largely unexamined among patients outside the intensive care unit, who represent the vast majority of patients treated with intravenous fluids. Methods/design This study, entitled Saline Against Lactated Ringer’s or Plasma-Lyte in the Emergency Department (SALT-ED), is a pragmatic, cluster, multiple-crossover trial at a single institution evaluating clinical outcomes of adults treated with 0.9% saline versus balanced crystalloids for intravenous fluid resuscitation in the emergency department. All adults treated in the study emergency department receiving at least 500 mL of isotonic crystalloid solution during usual clinical care and subsequently hospitalized outside the intensive care unit are included. Treatment allocation of 0.9% saline versus balanced crystalloids is assigned by calendar month, with study patients treated during the same month assigned to the same fluid type. The first month (January 2016) was randomly assigned to balanced crystalloids, with each subsequent month alternating between 0.9% saline and balanced crystalloids. For balanced crystalloid treatment, clinicians can choose either Lactated Ringer’s or Plasma-Lyte A©. The study period is set at 16 months, which will result in an anticipated estimated sample size of 15,000 patients. The primary outcome is hospital-free days to day 28, defined as the number of days alive and out of the hospital from the index emergency department visit until 28 days later. Major secondary outcomes include proportion of patients who develop acute kidney injury by creatinine measurements; major adverse kidney events by hospital discharge or day 30 (MAKE30), which is a composite outcome of death, new renal replacement therapy, and persistent creatinine elevation >200% of baseline; and in-hospital mortality. Discussion This ongoing pragmatic trial will provide the most comprehensive evaluation to date of clinical outcomes associated with 0.9% saline compared to physiologically balanced fluids in patients outside the intensive care unit. Trial registration ClinicalTrials.gov, NCT02614040 . Registered on 18 November 2015.

We sought datasets with granular age distributions of rotavirus-positive disease presentations among children <5 years of age, before the introduction of rotavirus vaccines. We identified 117 datasets and fit parametric age distributions to each country dataset and mortality stratum. We calculated the median age and the cumulative proportion of rotavirus gastroenteritis events expected to occur at ages between birth and 5.0 years. The median age of rotavirus-positive hospital admissions was 38 weeks (interquartile range [IQR], 25–58 weeks) in countries with very high child mortality and 65 weeks (IQR, 40–107 weeks) in countries with very low or low child mortality. In countries with very high child mortality, 69% of rotavirus-positive admissions in children <5 years of age were in the first year of life, with 3% by 10 weeks, 8% by 15 weeks, and 27% by 26 weeks. This information is critical for assessing the potential benefits of alternative rotavirus vaccination schedules in different countries and for monitoring program impact.

As part of the new Fisheries Act, Fisheries and Oceans Canada (DFO) has made it a priority to disseminate its data publicly. The project proposed here is to create an open-access data product that includes most of the historical temperature and salinity profiles collected in Northwest Atlantic Ocean and its Arctic gateways. This project does not aim to replace a potential database, but rather provides an easily accessible and quality-controlled product that can inform fisheries management and support DFO priorities such as the Ecosystem Approach to Fisheries Management, Marine Spatial Planning and the Blue Economy. The Canadian Atlantic Shelf Temperature-Salinity (CASTS) data product consists of 853 748 individual casts (as of 22 August 2025) collected in a geographical zone corresponding to [35–80° N] and [42–100° W] since 1873. The data sources used to make this product were gathered from multiple sources, including DFO regional archives at the Maurice-Lamontagne Institute (MLI), the Bedford Institute of Oceanography (BIO), and the Northwest Atlantic Fisheries Center (NAFC). Other sources of data include the Fisheries and Marine Institute of Memorial University, data from international ships of opportunity archived by the Marine Environmental Data Services (MEDS), and the Polar Data Catalog. This data product also offers new opportunities to review the changes in the ocean climate of Atlantic Canada, another priority of the Government of Canada. The analysis of these data collected over more than a century also reveals the profound changes undergone by the Northwest (NW) Atlantic Ocean during that period. Climate highlights include large decadal fluctuations of temperature and salinity throughout the entire zone, as well as sustained warming trends on the Scotian Shelf and the Bay of Fundy since the early 1990s, coinciding with an important freshening on the Newfoundland and Labrador Shelf during the same period. The CASTS data product is available at https://doi.org/10.20383/103.01462 (Coyne et al., 2023).

Background Saline, the intravenous fluid most commonly administered to critically ill adults, contains a high chloride content, which may be associated with acute kidney injury and death. Whether using balanced crystalloids rather than saline decreases the risk of acute kidney injury and death among critically ill adults remains unknown. Methods The Isotonic Solutions and Major Adverse Renal Events Trial (SMART) is a pragmatic, cluster-level allocation, cluster-level crossover trial being conducted between 1 June 2015 and 30 April 2017 in five intensive care units at Vanderbilt University Medical Center in Nashville, TN, USA. SMART compares saline (0.9% sodium chloride) with balanced crystalloids (clinician’s choice of lactated Ringer’s solution or Plasma-Lyte A®). Each intensive care unit is assigned to provide either saline or balanced crystalloids each month, with the assigned crystalloid alternating monthly over the course of the trial. All adults admitted to participating intensive care units during the study period are enrolled and followed until hospital discharge or 30 days after enrollment. The anticipated enrollment is approximately 14,000 patients. The primary outcome is Major Adverse Kidney Events within 30 days—the composite of in-hospital death, receipt of new renal replacement therapy, or persistent renal dysfunction (discharge creatinine ≥200% of baseline creatinine). Secondary clinical outcomes include in-hospital mortality, intensive care unit-free days, ventilator-free days, vasopressor-free days, and renal replacement therapy-free days. Secondary renal outcomes include new renal replacement therapy receipt, persistent renal dysfunction, and incidence of stage 2 or higher acute kidney injury. Discussion This ongoing pragmatic trial will provide the largest and most comprehensive comparison to date of clinical outcomes with saline versus balanced crystalloids among critically ill adults. Trial registration For logistical reasons, SMART was prospectively registered separately for the medical ICU (SMART-MED; ClinicalTrials.gov identifier: NCT02444988 ; registered on 11 May 2015; date of first patient enrollment: 1 June 2015) and the nonmedical ICUs (SMART-SURG; ClinicalTrials.gov identifier: NCT02547779 ; registered on 9 September 2015; date of first patient enrollment: 1 October 2015).