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In the present study, we sought to determine whether early pre-emptive scheduling of inferior vena cava filter (IVCF) removal during the preoperative IVCF placement visit would affect the IVCF removal rate.All electronically documented IVCF placements at a single institution were reviewed from April 2015 to July 2019. The baseline characteristics included age, the clinical indications for IVCF placement, inpatient/outpatient status, and type of IVCF placed. Statistical analysis was performed using the χA total of 599 patients (mean age, 68 years; 273 women and 326 men) had undergone technically successful IVCF placement. During the preoperative consent process for placement, 232 patients had been scheduled for IVCF removal within 3 months after placement. However, 367 patients had not been scheduled for removal at the preoperative consent process. The indications for placement included failure of anticoagulation, a contraindication to anticoagulation (eg, bleeding), preoperative prophylaxis, and others. Of the 232 patients scheduled for IVCF removal during preoperative consent for IVCF placement, 103 (44%) had undergone successful IVCF removal (mean interval from placement, 107 ± 100 days). Of the 367 nonscheduled patients, 89 (24%) had undergone successful IVCF removal (mean time, 184 ± 215 days). We found a significant improvement in the IVCF removal rate between the scheduled and nonscheduled patients (P .0001). Three patients (all from the scheduled group) had a clot burden within the IVCF, which meant they were inappropriate for removal. These patients were rescheduled and had eventually undergone uncomplicated removal.Scheduling IVCF removal during the placement encounter significantly increased the IVCF removal rate. This approach could be a viable option for institutions where clinic time and/or resources are limited or unavailable and for patients who have difficulty traveling for clinical evaluations.

Percutaneous cholecystostomy tubes (PCT) are utilized in the management of acute cholecystitis in patients deemed unsuitable for surgery. However, the drive for these decisions and the outcomes remain understudied. We sought to characterize the practices and utilization of PCT and evaluate associated outcomes at an urban medical center.Patients undergoing PCT placement over a 12-y study period ending May 2019 were reviewed. Demographics, clinical presentation, labs, imaging studies, and outcomes were abstracted. The primary and secondary outcomes were 30-d mortality and interval cholecystectomy, respectively.Two hundred and four patients met inclusion criteria: 59.3% were male with a median age of 67.5 y and a National Surgical Quality Improvement Program (NSQIP) risk of serious complication of 8.0%. Overall, 57.8% of patients were located in an intensive care unit setting. The majority (80.9%) had an ultrasound and 48.5% had a hepatobiliary iminodiacetic acid scan. The overall 30-d mortality was 31.9%: 41.5% for intensive care unit and 18.6% for ward patients (P0.01). Of patients surviving beyond 30 d (n = 139), the PCT was removed from 106 (76.3%), and a cholecystectomy was performed in 55 (39.6%) at a median interval of 58.0 d. A forward logistic regression identified total bilirubin (Adjusted Odds Ratio: 1.12, adjusted P0.01) and NSQIP risk of serious complication (Adjusted Odds Ratio: 1.16, adjusted P0.01) as the only predictors for 30-d mortality.Patients selected for PCT placement have a high mortality risk. Despite subsequent removal of the PCT, the majority of surviving patients did not undergo an interval cholecystectomy. Total bilirubin and NSQIP risk of serious complication are useful adjuncts in predicting 30-d mortality in these patients.

Inertial confinement fusion seeks to create burning plasma conditions in a spherical capsule implosion, which requires efficiently absorbing the driver energy in the capsule, transferring that energy into kinetic energy of the imploding DT fuel and then into internal energy of the fuel at stagnation. We report new implosions conducted on the National Ignition Facility (NIF) with several improvements on recent work [Phys. Rev. Lett. 120, 245003 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.245003; Phys. Rev. E 102, 023210 (2020)PRESCM2470-004510.1103/PhysRevE.102.023210]: larger capsules, thicker fuel layers to mitigate fuel-ablator mix, and new symmetry control via cross-beam energy transfer; at modest velocities, these experiments achieve record values for the implosion energetics figures of merit as well as fusion yield for a NIF experiment.

Self-induced plasma gratings are now routinely used in inertial confinement fusion experiments at the National Ignition Facility (NIF) to achieve precise spatio-temporal control of the laser energy deposition directly inside the fusion targets. This novel capability is enabled by applying a few Å wavelength shifts between different groups of beams, in order to control the direction and level of light scattering off these plasma gratings. A new wavelength tuning capability was added on the NIF in January 2020 to extend the range of applications of plasma gratings; such applications include the control of several asymmetry modes during the implosion, and mitigation of backscatter from stimulated Raman or Brillouin scattering.

Background Percutaneous cholecystostomy is performed by interventional radiologists for patients with calculous/acalculous cholecystitis who are poor candidates for cholecystectomy. Two anatomical approaches are widely utilized: transperitoneal and transhepatic. Purpose To compare the clinical outcomes of transperitoneal and transhepatic approaches to cholecystostomy catheter placement. Material and Methods From December 2007 to August 2015, 165 consecutive patients (97 men, 68 women) underwent either transperitoneal (n = 89) or transhepatic (n = 76) cholecystostomy at a single center. Indications were calculous cholecystitis (n = 21), acalculous cholecystitis (n = 35), hydrops (n = 1), gangrenous cholecystitis (n = 1), and other cholecystitis (n = 107). The most common high-risk co-morbidities were sepsis (n = 53) and cardiac (n = 11). Outcomes were compared using univariate and multivariable analysis. Results Post-procedure outcomes included tube dislodgement (transperitoneal [n = 6] and transhepatic [n = 3], P = 0.44), bile leak (transperitoneal [n = 5], transhepatic [n = 1], P = 0.14), gallbladder hemorrhage (transperitoneal [n = 2]; transhepatic [n = 3], P = 0.52), duodenal fistula (transperitoneal [n = 0], transhepatic [n = 1], P = 0.27), repeat cholecystostomy (transperitoneal [n = 1], transhepatic [n = 3], P = 0.27), and repeat cholecystitis requiring separate admission (transperitoneal [n = 6], transhepatic [n = 10], P = 0.15). All complications were Common Terminology Criteria for Adverse Events grade Conclusion There were no significant differences in short-term complications after transperitoneal and transhepatic approaches to percutaneous cholecystostomy catheter placement.

Transportation investments have the potential to improve health, but readily available data to guide transportation decisions that could promote health are limited. In October 2015, the U.S. Department of Transportation (USDOT) and the Centers for Disease Control and Prevention (CDC) released the Transportation and Health Tool (THT). The tool is a resource to help transportation professionals in states and metropolitan areas access data about transportation and health in their jurisdictions and stimulate discussions on how to improve public health through transportation planning and policy. To develop the tool, a multidisciplinary team identified 190 possible data indicators. Using input from expert panel workshops and criteria that addressed data availability, geographic scale, timeliness, feasibility, validity, and topic area, the team selected 14 transportation and health indicators that covered the four priority topic areas of safety, active transportation, air quality, and connectivity. The THT contains the raw values for each indicator and a standardized score to enable comparisons. Additionally, the THT contains 25 evidence-based strategies that can help practitioners in states and metropolitan areas take action to improve health outcomes.

Recent experiments in the study of inertial confinement fusion (ICF) at the National Ignition Facility (NIF) in the United States have reached the so-called alpha-heating regime1–3, in which the self-heating by fusion products becomes dominant, with neutron yields now exceeding 1 × 1016 (ref. 4) However, there are still challenges on the path towards ignition, such as minimization of the drive asymmetry, suppression of laser-plasma instabilities, and mitigation of fabrication features5. In addition, in the current cylindrical-hohlraum indirect drive schemes for ICF, a strong limitation is the inefficient (≤10%) absorption of the laser-produced hohlraum X-rays by the capsule as set by relative capsule-to-hohlraum surface areas. Here we report an experiment demonstrating ~30% energy coupling to an aluminium capsule in a rugby-shaped6, gold hohlraum. This high coupling efficiency can substantially increase the tolerance to residual imperfections and improve the prospects for ignition, both in mainline single-shell hot-spot designs and potential double-shell targets. High coupling efficiency between laser-induced hohlraum X-rays and targets is essential for reaching long-sought regimes for viable inertial confinement fusion. Experiments with a rugby hohlraum shape and an improved capsule now allow demonstration of more than 30%.

PURPOSE: To identify baseline characteristics and long-term prognostic factors in non-transplant patients with unresectable hepatocellular carcinoma (HCC) who had prolonged survival after treatment with yttrium-90 radioembolization (Y90). MATERIALS AND METHODS: 67 "Super Survivors" (defined as ≥3 years survival after Y90) were identified within our 1,000-patient Y90 database (2003–2017). Baseline imaging and follow-up occurred at 1 months and every 3 months thereafter. Overall survival (OS) was calculated with Kaplan-Meier estimates with log-rank test in sub-groups: Child-Pugh (CP) score, distribution of disease, portal vein thrombus (PVT), and technique (segmental vs lobar Y90). RESULTS: Median age 69.5 years (range: 45–94 years); 69% male; 60% solitary HCC; 79% unilobar disease; 12% PVT; 10% ascites; Barcelona Clinic Liver Cancer Stage A-54%/B-28%/C-16%/D-2%; CP A-70%/B-28%/C-2%. Longest baseline tumor diameter was 5.4 ± 4.0cm (mean ± SD). All patients had an imaging response (either partial or complete response). Median OS was 67.5 months (95% confidence interval; 55.2–82.5). CP score and main PVT stratified median OS (p=0.0007 and p=0.0187, respectively). Beyond 3 years, segmental vs lobar Y90 was associated with improved OS with a median OS of 80.2 vs 46.7 months, respectively (p=0.0024). Dosing >200Gy was not a significant predictor of improved OS. CONCLUSIONS: Super survivors spanning the BCLC Staging System maintained durable OS after radioembolization that was stratified by the extent of underlying liver disease. The common variable among all patients was an imaging response. Segmental vs lobar Y90 may have a long-term associated OS benefit.

We report survival outcomes for patients with advanced-stage hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) treated with 90Y radioembolization. Methods: With institutional review board approval, we searched our prospectively acquired database for 90Y patients treated between 2003 and 2017. Inclusion criteria were patients who had HCC with tumor PVT. Patients with metastases were excluded. Laboratory data were collected at baseline and 1 mo after 90Y radioembolization. Toxicity grades were reported according to the Common Terminology Criteria for Adverse Events, version 4.0, and long-term survival outcomes were reported and stratified by Child-Pugh class (CP). Overall survival was calculated using the Kaplan-Meier method. Multivariate analysis was performed using Cox proportional hazards regression. A subanalysis for patients with a high level of α-fetoprotein (AFP) (>100 ng/dL) was conducted. Results: In total, 185 patients with HCC PVT underwent 90Y radioembolization. Seventy-four (40%) were CP-A, 51 (28%) were CP-B7, and 60 (32%) were ≥CP-B8. New albumin, bilirubin, and alkaline phosphatase grade 3/4 toxicities were, respectively, 3%, 10%, and 0% for CP-A; 14%, 12%, and 6% for CP-B7; and 23%, 32%, and 3% for ≥CP-B8. Median overall survival for CP-A patients was 13.3 mo (95% confidence interval [CI], 8.7-15.7 mo). CP-B7 and ≥CP-B8 patients exhibited median overall survival of 6.9 mo (95% CI, 5.3-10.1 mo) and 3.9 mo (95% CI, 2.9-5.0 mo), respectively. Significant overall survival prognosticators on univariate analysis were albumin, bilirubin, ascites, tumor size 5 cm or smaller, focality, distribution, infiltration, Eastern Cooperative Oncology Group status, AFP level, and PVT extent. Multivariate analysis showed the prognosticators of overall survival to be bilirubin, no ascites, tumor size 5 cm or smaller, solitary lesion, baseline AFP level lower than 100 ng/dL, and Eastern Cooperative Oncology Group status. Of 123 patients with a high AFP level (>100 ng/dL), 12 patients achieved restored normal AFP levels (

Transarterial radioembolization is a novel therapy that has gained rapid clinical acceptance for the treatment of hepatocellular carcinoma (HCC). Segmental radioembolization [also termed radiation segmentectomy (RS)] is a technique that can deliver high doses (> 190 Gy) of radiation selectively to the hepatic segment(s) containing the tumor. The aim of this comprehensive review is to provide an illustrative summary of the most relevant imaging findings encountered after radiation segmentectomy. A 62-patient cohort of Child-Pugh A patients with solitary HCC

We present direct measurements of electron temperature variations within an inertially confined deuterium-tritium plasma caused by localized mix of higher-Z materials into the central hot spot. The data are derived from newly developed differentially filtered penumbral imaging of the bremsstrahlung continuum emission. Our analysis reveals distinct localized emitting features in the stagnated hot-spot plasma, and we infer spatial variations in the electron temperature: the mixed region is 660±130eV colder than the surrounding hot-spot plasma at 3.26±0.11keV. Our analysis of the energy flow shows that we measure approximately steady-state conditions where the radiative losses in the mix region are balanced by heat conduction from the surrounding hot deuterium-tritium plasma.

Objective To increase the availability and accessibility of standardized environmental health data for public health surveillance and decision-making. Introduction In 2002, the United States (US) Centers for Disease Control and Prevention (CDC) launched the National Environmental Public Health Tracking Program (Tracking Program) to address the challenges in environmental health surveillance described by the Pew Environmental Commission (1). The report cited gaps in our understanding of how the environment affects our health and attributed these gaps to a dearth of surveillance data for environmental hazards, human exposures, and health effects. The Tracking Program’s mission is to provide information from a nationwide network of integrated health and environmental data that drives actions to improve the health of communities. Accomplishing this mission requires a range of expertise from environmental health scientists to programmers to communicators employing the best practices and latest technical advances of their disciplines. Critical to this mission, the Tracking Program must identify and prioritize what data are needed, address any gaps found, and integrate the data into the network for ongoing surveillance. Methods The Tracking Program identifies important environmental health topics with data challenges based on the recommendations in the Pew Commission report as well as input from federal, state, territorial, tribal, and local partners. For each topic, the first step is to formulate the key surveillance question, which includes identifying the decision-maker or end user. Next, available data are evaluated to determine if the data can answer the question and, if not, what enhancements or new data are needed. Standards are developed to establish data requirements and to ensure consistency and comparability. Standardized data are then integrated into the network at national, state, and local levels. Standardized measures are calculated to translate the data into the information needed. These measures are then publically disseminated via national, state, and local web-based portals. Data are updated annually or as they are available and new data are added regularly. All data undergo a multi-step validation process that is semi-automated, routinized, and reproducible. Results The first set of nationally consistent data and measures (NCDM) was released in 2008 and covered 8 environmental health topics. Since then the NCDM have grown to cover 14 topics. Additional standardized data and measures are integrated into the national network resulting in 23 topics with standardized 450 measures (Figure). On the national network, measures can be queried via the Data Explorer, viewed in the info-by-location application, or connected to via the network’s Application Program Interface (API). On average, 15,000 and 3300 queries are run every month on the Data Explorer and the API respectfully. Additional locally relevant data are available on state and local tracking networks. Gaps in data have been addressed through standards for new data collections, models to extend available data, new methodologies for using existing data, and expansion of the utility of non-traditional public health data. For example, the program has collaborated with the Environmental Protection Agency to develop daily estimates of fine particulate matter and ozone for every county in the conterminous US and to develop the first national database of standardized radon testing data. The program also collaborated with the National Aeronautics and Space Administration and its academic partners to transform satellite data into data products for public health. The Tracking Program has analyzed the data to address important gaps in our understanding of the relationship between negative health outcomes and environmental hazards. Data have been used in epidemiologic studies to better quantify the association between fine particulate matter, ozone, wildfire smoke, and extreme heat on emergency department visits and hospitalizations. Results are translated into measures of health burden for public dissemination and can be used to inform regulatory standards and public health interventions. Conclusions The scope of the Tracking Program’s mission and the volume of data within the network requires the program to merge traditional public health expertise and practices with current technical and scientific advances. Data integrated into the network can be used to (1) describe temporal and spatial trends in health outcomes and potential environmental exposures, (2) identify populations most affected, (3) generate hypotheses about associations between health and environmental exposures, and (4) develop, guide, and assess the environmental public health policies and interventions aimed at reducing or eliminating health outcomes associated with environmental factors. The program continues to expand the data within the network and the applications deployed for others to access the data. Current data challenges include the need for more temporally and spatially resolved data to better understand the complex relationships between environmental hazards, health outcomes, and risk factors at a local level. National standards are in development for systematically generating, analyzing, and disseminating small area data and real-time data that will allow for comparisons between different datasets over geography and time. References 1. Pew Environmental Health Tracking Project Team. America’s Environmental Health Gap: Why the Country Needs a Nationwide Health Tracking Network. Johns Hopkins School of Hygiene and Public Health, Department of Health Policy and Management; 2000.

Colorectal cancer is the third leading cause of cancer death in the United States. Although hepatic excision is the first-line treatment for colorectal liver metastasis (CRLM), few patients are candidates. Locoregional therapy (LRT) encompasses minimally invasive techniques practiced by interventional radiology. These include ablative treatments (radiofrequency ablation, microwave ablation, and cryosurgical ablation) and transcatheter intra-arterial therapy (hepatic arterial infusion chemotherapy, transarterial "bland" embolization, transarterial chemoembolization, and radioembolization with yttrium 90). The National Comprehensive Cancer Network recommends LRT for unresectable CRLM refractory to chemotherapy. The following is a review of LRT in CRLM, including salient features, advantages, limitations, current roles, and future considerations.

To assess the feasibility of conducting pretreatment mesenteric angiography, coil embolization, 99mTc macroaggregated albumin (99mTc-MAA) scintigraphy, and 90Y radioembolization treatment in a single, same-day, combined outpatient encounter. This was a retrospective study of 78 patients treated during the period 2008 – 2015 who were managed in a single outpatient encounter under the guidance of the Interventional Radiology Department and The Nuclear Medicine Department. Pretreatment planning was performed by reviewing baseline imaging and estimated perfused liver volume bearing the tumor. The region of interest was estimated using 3-D software; this value was used for dosimetry planning. Maximum lung shunting fractions of 10 % for hepatocellular carcinoma and 5 % for liver metastases were assumed. Subsequently, hepatic angiography and 99mTc-MAA scintigraphy were performed followed by 90Y treatment in one outpatient encounter. Total in-room procedure time was recorded. All patients underwent same-day angiography, 99mTc-MAA scintigraphy and 90Y radioembolization. Of the 78 patients, 16 received multiple segmental treatments to both lobes, 44 received treatment to the right lobe, and 18 received treatment to the left lobe. The median dose was 106 Gy. The median number of 90Y vials needed was two (range one to six). The median in-room time was 160 min (75 – 250 min). The residential status of the patients was as follows, 18 % (14/78) were local residents, 55 % (43/78) traveled from outside the city limits, 18 % (14/78) were from out-of-state, and 9 % (7/78) were resident abroad. Of the 78 patients, 61 (77 %) had hepatocellular carcinoma, and 17 (22 %) had liver metastases. The median lung dose was 3.5 Gy. This study demonstrated the feasibility of same-day 90Y evaluation and treatment while maintaining the principles of safe and effective 90Y infusion including tumoricidal dosimetry (lobar, segmentectomy), minimization of nontarget flow, and minimization of lung dose. This paradigm translates into expeditious cancer care and significant cost savings.

Inertial confinement fusion, based on laser-heating a deuterium–tritium mixture, is one of the approaches towards energy production from fusion reactions. Now, record energy-yield experiments are reported—bringing us closer to ignition conditions.

Hepatic metastases of colorectal carcinoma are a leading cause of cancer-related mortality. Most colorectal liver metastases become refractory to chemotherapy and biologic agents, at which point the median overall survival declines to 4–5 mo. Radioembolization with 90Y has been used in the salvage setting with favorable outcomes. This study reports the survival and safety outcomes of 531 patients treated with glass-based 90Y microspheres at 8 institutions, making it the largest 90Y study for patients with colorectal liver metastases. Methods: Data were retrospectively compiled from 8 institutions for all 90Y glass microsphere treatments for colorectal liver metastases. Exposure to chemotherapeutic or biologic agents, prior liver therapies, biochemical parameters before and after treatment, radiation dosimetry, and complications were recorded. Uni- and multivariate analyses for predictors of survival were performed. Survival outcomes and clinical or biochemical adverse events were recorded. Results: In total, 531 patients received 90Y radioembolization for colorectal liver metastases. The most common clinical adverse events were fatigue (55%), abdominal pain (34%), and nausea (19%). Grade 3 or 4 hyperbilirubinemia occurred in 13% of patients at any time. The median overall survival from the first 90Y treatment was 10.6 mo (95% confidence interval, 8.8–12.4). Performance status, no more than 25% tumor burden, no extrahepatic metastases, albumin greater than 3 g/dL, and receipt of no more than 2 chemotherapeutic agents independently predicted better survival outcomes. Conclusion: This multiinstitutional review of a large cohort of patients with colorectal liver metastases treated with 90Y radioembolization using glass microspheres has demonstrated promising survival outcomes with low toxicity and low side effects. The outcomes were reproducible and consistent with prior reports of radioembolization.

Fuel areal density (ρR) of all recent indirectly driven, cryogenically-layered DT implosions at the National Ignition Facility (NIF) show a deficit when compared to simulations. Across all designs, experimental ρR is lower than in 1D simulations without alpha energy or momentum deposition. A series of layered implosions were fielded at NIF to assess the impact of fuel-ablator instability, as caused by M-band preheat, on lower-than-expected fuel areal density. The stability of the fuel-ablator interface is modified by varying the Atwood number through a series of experiments where capsules were fielded with different ablator dopant levels. A key finding of this campaign is that optimization of 1D physics (shock timing) dominates stabilization of the fuel-ablator interface.

Experiments on imploding an Al capsule in a Au rugby hohlraum with up to a 1.5 MJ laser drive were performed on the National Ignition Facility (NIF). The capsule diameter was 3.0 mm with ∼1 MJ drive and 3.4 mm with ∼1.5 MJ drive. Effective symmetry tuning by modifying the rugby hohlraum shape was demonstrated, and good shell symmetry was achieved for 3.4 mm capsules at a convergence of ∼10. The nuclear bang time and the shell velocity from simulations agree with experimental data, indicating ∼500 kJ coupling with 1.5 MJ drive or ∼30% efficiency. The peak velocity reached above 300 km/s for a 120 μm-thick Al capsule. The laser backscatter inside the low-gas-filled rugby hohlraum was very low (

Cross beam energy transfer (CBET), invoked by setting a wavelength difference, Δλ, between inner and outer beam cones, can be used to increase the drive on the waist in indirectly driven inertial confinement fusion experiments at the National Ignition Facility (NIF). Historically, hot spot symmetry control in capsule implosions in high (≥0.9 mg/cm3 4He) gas fill Hohlraums was enabled by substantial CBET. However, these implosion designs suffered from inflight symmetry swings, high SRS backscatter on the inner cones, and significant hot electron generation posing a threat to DT fuel preheat. Subsequent experiments in larger, low (≤0.6 mg/cm3 4He) gas fill Hohlraums demonstrated round implosions by varying the inner cone fraction throughout the laser drive at Δλ = 0 A while keeping backscatter and hot electron generation very low. To enable driving larger capsules at a given Hohlraum size, additional tools for implosion symmetry control are required. With this goal in mind, this paper presents a detailed experimental study of using CBET in low gas fill Hohlraums near NIF's current peak power capability. We find a ∼2.5× higher sensitivity of the P2 Legendre mode with respect to Δλ changes compared to that of high gas fill designs. We attribute this observation to the fact that backscatter remains very low and that CBET remains in a linear regime, as suggested by simulations. As a result, a much smaller Δλ of order 1 A is sufficient for sustaining implosion symmetry while keeping laser-to-Hohlraum coupling high and hot electron generation very low. While this study used plastic ablator capsules, our findings can be generalized to other ablator materials and, hence, show great promise for using wavelength detuning as a strong lever for implosion symmetry control in future low gas fill designs that require smaller case to capsule ratios in order to increase the energy coupled to the capsule.

Experimental results from indirectly driven inertial confinement fusion experiments testing the performance gained from using an alternate capsule tent support are reported. The polar tent describes an alternate geometry for the thin membrane used to support the Deuterium–Tritium (DT) filled capsule. Here, the contact area is reduced by 23 times by locating the tent support close to the poles of the capsule. The polar tent experiments are repeats of previous 3 shock 1.63 MJ, 400 TW high foot experiments and use a 165 μm thick silicon doped carbon hydrogen plastic (CH) shell. Using the polar tent support, we report a DT neutron yield of 1.07 × 10 16, 76% higher than the expected Y D T ∝ V 7.7 scaling. This is, at the time of writing, the highest neutron yield to date from a CH shell implosion. Furthermore, we find that the inferred pressure when using the polar tent is significantly above the model based on analytic scaling even when accounting for tent effects. Analysis of x-ray and neutron images shows the reduction of lobes produced by nominal tent features. The reduction of these features in the polar tent experiments leads to decreased low mode (P2 and P4) asymmetry compared to the nominal tent results.

The yield and fuel compression trends for the NIF indirect-drive cryogenically-layered DT implosions is empirically examined across all ablators (CH, C and Be) and design in-flight adiabats between 1.5 and 3. Higher compression is observed for a lower design adiabat. Within a design adiabat, compression increases for shorter coast implosions but only if have optimized shock timing. The sensitivity of compression to coast time appears less for higher adiabat designs. Across all designs and ablators, the best DT neutron yields follow the same 1D theoretical curve versus peak velocity, but only if normalize by capsule scale rather than fuel mass and thickness. Shots with reduced yields can be explained by having long coast time, high hot spot mix or know capsule imperfections. Repeat “Standard Candle” shock timing and gas implosions, and DT layered implosions normalized for scale and velocity, reveal adequate reproducibility in shock timing, implosion drive symmetry, compression and yield for the majority of shots. The level of reproducibility is also consistent with known uncertainties and imperfections in initial laser and capsule parameters and outputs. We thus conclude there is no evidence of a significant random unknown variable in these NIF implosions. The scaled yield reproducibility is such that the effect of design improvements increasing yield on any given shot by at least 40% can be deemed statistically significant.

We describe the overall performance of the major indirect-drive inertial confinement fusion campaigns executed at the National Ignition Facility. With respect to the proximity to ignition, we can describe the performance of current experiments both in terms of no-burn ignition metrics (metrics based on the hydrodynamic performance of targets in the absence of alpha-particle heating) and in terms of the thermodynamic properties of the hotspot and dense fuel at stagnation—in particular, the hotspot pressure, temperature, and areal density. We describe a simple 1D isobaric model to derive these quantities from experimental observables and examine where current experiments lie with respect to the conditions required for ignition.

Stimulated Raman scattering (SRS) has been explored comprehensively in planar-geometry experiments at the National Ignition Facility in conditions relevant to the corona of inertial confinement fusion ignition-scale direct-drive targets. These experiments at measured electron temperatures of 4 to 5 keV simulated density scale lengths L n of 400 to 700 μm, and laser intensities at the quarter-critical density of up to 1.5 × 1015 W/cm2 have determined SRS thresholds and the scaling behavior of SRS for various beam geometries. Several SRS mechanisms, including saturated absolute SRS near the quarter-critical density and additional SRS, including near-backscatter or sidescatter at lower densities, have been identified. Correlation of time-dependent SRS at densities ∼0.15 to 0.21 of the critical density with hot-electron signatures as well as the magnitudes of these signatures across different experiments, is observed. Further modeling work is needed to definitively identify the density region in which hot electrons are generated and will guide SRS and hot-electron preheat mitigation strategies for direct-drive-ignition designs.

We are reporting on a series of indirect-drive 0.9-scale CH capsule implosions (inner radius = 840 μm) fielded in low gas-fill (0.6 mg/cm3) hohlraums of 6.72 mm diameter at the National Ignition Facility. Thanks to the 11%-reduction of the capsule size at a given hohlraum diameter compared to previously tested full-scale capsules, we achieved good hot spot symmetry control near 33% cone-fraction and without the need to invoke cross beam energy transfer. As a result, we achieved a hot spot pressure of 280 ± 40 Gbar, which is the highest pressure demonstrated in layered DT implosions with CH capsules to date. Pushing this design to higher velocity resulted in a reduction of neutron yield. Highly resolved capsule simulations suggest that higher Au M-shell preheat resulted in an increase in Atwood number at the ablator–ice interface, which leads to increased fuel-ablator instability and mixing. The results reported here provide important scaling information for next-generation CH designs.

Recent experiments systematically studied subscale beryllium-capsule implosions on NIF [A.B. Zylstra et al., Phys. Plasmas 26, 052707 (2019)], finding that the performance was well explained by invoking an inline model for mix at the fuel ablator interface. This model is optimistic about the performance of full-scale beryllium implosions, motivating an exploratory study on tactics for fielding larger capsules within the current limits of power and energy available at NIF. Here we report the results of that work, finding that using a ‘picketless’ pulse would allow a 25% increase in capsule size, which is predicted to substantially improve performance.

We investigate cross-beam energy transfer (CBET), where power is transferred from one laser beam to another via a shared ion acoustic wave in hohlraums with low-gas-fill density as a tool for late-time symmetry control for long-pulse (greater than $10\phantom{\rule{0.28em}{0ex}}\mathrm{ns}$) inertial confinement fusion (ICF) and laboratory astrophysics experiments. We show that the radiation drive symmetry can be controlled and accurately predicted during the foot of the pulse (until the rise to peak power), which is important for mitigating areal density variations in the compressed fuel in ICF implosions. We also show that the effective inner-beam drive after CBET is much greater than observed in previous high-gas-filled-hohlraum experiments, which is thought to be a result of less inverse bremsstrahlung absorption of the incident laser light and reduced (by more than 10 times) stimulated Raman scattering (and Langmuir wave heating). With the inferred level of inner-beam drive after transfer, we estimate that more than $1.25$ times larger plastic capsules could be fielded in this platform with sufficient laser-beam propagation to the waist of the hohlraum. We also estimate that a full-scale plastic capsule, $1100\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ in capsule radius, would require $\ensuremath{\sim}1--2\phantom{\rule{0.16em}{0ex}}\AA{}$ of $1\ensuremath{\omega}$ wavelength separation between the outer and inner beams to achieve a symmetric implosion in this platform.

To assess changes in imaging and volume characteristics of the prostate gland by magnetic resonance (MR) following prostatic artery embolization (PAE) for benign prostate hyperplasia. With IRB approval, we analyzed prospectively acquired MR data of PAE patients at baseline and 6-month following treatment from 2015 to 2017. We reviewed prostate MRs looking for sequelae of embolization [changes in signal intensity and/or enhancement, infection/inflammation, infarction, edema, and change in intravesical prostatic protrusion (IPP)]. We calculated the total volume (TV) and central gland volumes (CGV) using DynaCAD® and measured change in volumes. Analyses were performed using SPSS with p