Fibrosis Stage-specific Incidence of Hepatocellular Cancer After Hepatitis C Cure With Direct-acting Antivirals: A Systematic Review and Meta-analysis.

BACKGROUND & AIMS: Hepatitis C virus (HCV) eradication with direct-acting antivirals reduces hepatocellular carcinoma (HCC) risk. Pooled HCC incidence rates by cirrhosis status and fibrosis stage have not been estimated using meta-analysis. METHODS: We searched PubMed, Web of Science, Embase, and Cochrane Library from January 1, 2014 to December 31, 2020 to identify studies assessing HCC incidence or outcomes by cirrhosis status, in adults with HCV who achieved sustained virologic response (SVR) after direct-acting antivirals. Pooled estimates were obtained using random-effects modeling. Subgroup, sensitivity, and meta-regression analyses were performed to evaluate heterogeneity. RESULTS: We included 31 studies involving 27,711 patients with cirrhosis (mean follow-up, 2.1 years) and 11 studies involving 32,123 patients without cirrhosis (mean follow-up, 2.6 years). HCC incidence was 2.99/100 person-years (95% confidence interval [CI], 2.52-3.54; I2 = 75%) in patients with cirrhosis, 0.47/100 person-years (95% CI, 0.32-0.70, I2 = 71%) in patients without cirrhosis, and 0.63/100 person-years (95% CI: 0.34-1.20, I2 = 0%) in stage 3 (F3) fibrosis. Among patients with cirrhosis, HCC incidence was highest in studies with <1 year of follow-up (6.17/100 person-years [95% CI, 3.73-10.19]) and progressively lower in studies with longer follow-up (1-2 years: 2.75/100 person-years [95% CI, 2.48-3.06]; 2-3 years: 2.90/100 person-years [95% CI, 1.90-4.44]; ≥3 years: 1.83/100 person-years [95% CI, 0.88-3.80]). CONCLUSION: Pooled HCC incidence after SVR in patients with cirrhosis was very high (2.99/100 person-years) but may be declining as longer time accrues after SVR. In patients without cirrhosis, including F3 fibrosis, HCC incidence was lower than thresholds associated with cost-effective HCC screening. In patients with F3 fibrosis, the lack of between-study heterogeneity provides strong evidence that HCC screening may not be warranted.

Analysis of Speaker Introduction Formality by Gender at the American College of Gastroenterology 2020 Annual Scientific Meeting.

BACKGROUND: Gender-based differences in the use of professional titles during speaker introductions have been described in other medical specialties. AIMS: Our primary aim was to assess gender-based differences in the formality of speaker introductions at the American College of Gastroenterology 2020 Virtual Annual Scientific Meeting. Our secondary aim was to assess gender-based differences in the formality of speaker self-introductions. METHODS: Reviewed presentations from the American College of Gastroenterology Annual Meeting for gender-based differences in professional title use during speaker introductions and self-introductions. RESULTS: Speakers included 29 women (37.2%) and 49 men (62.8%). We found no significant gender differences in the use of professional titles by introducers (t(67) = - 0.775, p = 0.441) or in self-introductions (36.4% of women vs. 41.9% of men, t(63) = 0.422, p = 0.674). CONCLUSION: The lack of gender differences in professional title use may represent a novel advantage of virtual meeting formats or suggest increased attention to gender bias in introductions.

An Axially Continuous Graphene-Copper Wire for High-Power Transmission: Thermoelectrical Characterization and Mechanisms.

The demand for high-power electrical transmission continues to increase with technical advances in electric vehicles, unmanned drones, portable devices, and deployable military applications. In this study, significantly enhanced electrical properties (i.e., a 450% increase in the current density breakdown limit) are demonstrated by synthesizing axially continuous graphene layers on microscale-diameter wires. To elucidate the underlying mechanisms of the observed enhancements, the electrical properties of pure copper wires and axially continuous graphene-copper (ACGC) wires with three different diameters are characterized while controlling the experimental conditions, including ambient temperature, gases, and pressure. The study reveals that the main mechanism that allows the application of extremely large current densities (>400 000 A cm-2 ) through the ACGC wires is threefold: the continuous graphene layers considerably improve: 1) surface heat dissipation (224% higher), 2) electrical conductivity (41% higher), and 3) thermal stability (41.2% lower resistivity after thermal cycles up to 450 °C), compared with pure copper wires. In addition, it is observed, through the use of high-speed camera images, that the ACGC wires exhibit very different failure behavior near the current density limit, compared with the pure copper wires.

Relationship Between Confidence, Gender, and Career Choice in Internal Medicine.

BACKGROUND: Understanding factors in internal medicine (IM) resident career choice may reveal important needed interventions for recruitment and diversity in IM primary care and its subspecialties. Self-reported learner confidence is higher in men than in women in certain areas of practicing medicine, but has never been explored as a factor in career choice. OBJECTIVE: The purpose of this study is to elucidate associations between confidence, gender, and career choice. DESIGN: IM residents completed a 31-item survey rating confidence in procedural, clinical, and communication skills on a 9-point Likert scale. Residents also reported anticipated career choice and rated influence of factors. Associations between gender and confidence scale scores, gender and career choice, and confidence and career choice were analyzed using t tests, ANOVA, and multiple linear regression controlled for postgraduate year (PGY), institution, and specialty choice. PARTICIPANTS: 292 IM residents at Northwestern and University of Texas (UT) Southwestern MAIN MEASURES: Resident gender, self-reported confidence, career choice KEY RESULTS: Response rate was 79.6% (n = 292), of them 50.3% women. Overall self-reported confidence increased with training (PGY-1 4.9 (1.1); PGY-2 6.2 (1.0); PGY-3 7.4 (1.0); p < 0.001). Men had higher confidence than women (men 6.6 (1.5); women 6.3 (1.4), p = 0.06), with the greatest difference in procedures. High confidence in men was associated with choice of procedural careers, whereas there was no association between confidence and career in women. CONCLUSIONS: This is the first study demonstrating a gender difference in self-reported confidence and career choice. There is a positive correlation in men: higher self-reported confidence with procedural specialties, lower with general internal medicine. Women's self-reported confidence had no association. Further investigation is needed to elucidate causative factors for differences in self-reported confidence by gender, and whether alterations in level of self-reported confidence produce a downstream effect on career choice.

Low Awareness of Nonalcoholic Fatty Liver Disease in a Population-Based Cohort Sample: the CARDIA Study.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States, yet little is known about NAFLD awareness in individuals with incidental fatty liver on imaging. OBJECTIVE: To assess the level of awareness of imaging-defined NAFLD among individuals with and without metabolic risk factors. DESIGN: Cross-sectional analysis within a prospective longitudinal population-based cohort study conducted in four U.S. cities. PARTICIPANTS: Adults age 43 to 55 years enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study who underwent computed tomography and a personal health questionnaire at the year 25 exam (2010-2011, n = 2788). MAIN MEASURES: NAFLD was defined as liver attenuation ≤ 51 Hounsfield units after exclusion of other causes of liver fat. Participants were considered "NAFLD aware" if they reported being told previously by a doctor or nurse that they had "fatty liver." KEY RESULTS: NAFLD prevalence was 23.9%. Only 16 of 667 (2.4%) participants with CT-defined NAFLD were aware of a NAFLD diagnosis. NAFLD aware participants were more likely to be white (81.3% vs. 53.5%, p = 0.03) and have the metabolic syndrome (87.5% vs. 59.3%, p = 0.02) and/or hypertension (75.0% vs. 50.2%, p = 0.05). In multivariable analyses adjusted for demographics, metabolic syndrome and hypertension remained predictive of NAFLD awareness. CONCLUSION: There is low awareness of NAFLD among individuals with hepatic steatosis on imaging, even among those with metabolic risk factors. These findings highlight an opportunity to raise public and practitioner awareness of NAFLD with the goal of increasing diagnosis and implementing early treatment strategies.

Plasma renin activity, response to aliskiren, and clinical outcomes in patients hospitalized for heart failure: the ASTRONAUT trial.

AIMS: The direct renin inhibitor, aliskiren, is known to reduce plasma renin activity (PRA), but whether the efficacy of aliskiren varies based on an individual's baseline PRA in patients hospitalized for heart failure (HF) is presently unknown. We characterized the prognostic value of PRA and determined if this risk is modifiable with use of aliskiren. METHODS AND RESULTS: This pre-specified neurohormonal substudy of ASTRONAUT analysed all patients hospitalized for HF with ejection fraction (EF) ≤40% with available baseline PRA data (n = 1306, 80.9%). Risk associated with baseline PRA and short-term changes in PRA from baseline to 1 month was modelled with respect to 12-month clinical events. Median baseline PRA was 3.0 (interquartile range 0.6-16.4) ng/mL/h. Aliskiren significantly reduced PRA early after treatment initiation through 12-month follow-up compared with placebo (P < 0.001). The lowest baseline PRA quartile (<0.6 ng/mL/h) was independently predictive of lower all-cause mortality [adjusted hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.31-0.81] and the composite of cardiovascular mortality and HF hospitalization (adjusted HR 0.57, 95% CI 0.40-0.79). Delta log-normalized PRA (from baseline to 1 month) was not predictive of either primary endpoint at 12 months (P ≥ 0.43). The prognostic value of baseline PRA and short-term changes in PRA did not vary by randomization to aliskiren or placebo (interaction P ≥ 0.13). CONCLUSIONS: Plasma renin activity is reduced early and durably by aliskiren, but this did not translate into improved clinical outcomes in ASTRONAUT. Baseline PRA or short-term reduction in PRA do not identify a subgroup who may preferentially benefit from direct renin inhibition. Clinical Trial Registration ClinicalTrials.gov Unique Identifier: NCT00894387.

Electronic Transport in Bilayer MoS2 Encapsulated in HfO2.

The exact nature of the interface between a two-dimensional crystal and its environment can have a significant impact on the electronic transport within the crystal, and can place fundamental limitations on transistor performance and long-term functionality. Two-dimensional transition-metal dichalcogenides are a new class of transistor channel material with electronic properties that can be tailored through dielectric engineering of the material/environmental interface. Here, we report electrical transport measurements carried out in the insulating regime of bilayer molybdenum disulfide, which has been encapsulated within a high-κ hafnium oxide dielectric. Temperature- and carrier-density-dependent measurements show that for T < 130 K the transport is governed by resonant tunneling, and at T = 4.2 K the tunneling peak lineshape is well-fitted by a Lorentzian with an amplitude less than e2/h. Estimates of tunneling time give τ ∼ 1.2 ps corresponding to a frequency f ∼ 0.84 THz. The tunneling processes are observable up to T ∼ 190 K (more than a factor of 6 higher than that previously reported for MoS2 on SiO2) despite the onset of variable range hopping at T ∼ 130 K, demonstrating the coexistence of the two transport processes within the same temperature range. At constant temperature, varying the Fermi energy allows experimental access to each transport process. The results are interpreted in terms of an increase in charge carrier screening length and a decrease in electron-phonon coupling induced by the hafnium oxide. Our results represent the first demonstration of the intermediate tunneling-hopping transport regime in a two-dimensional material. The results suggest that interface engineering may be a macroscopic tool for controlling quantum transport within such materials as well as for increasing the operating temperatures for resonant-tunneling devices derived from such materials, with applications in high-frequency electronics and logic devices.

Removal of sodium dodecyl sulfate surfactant from aqueous dispersions of single-wall carbon nanotubes.

A reagent-based treatment method was developed for the removal of sodium dodecyl sulfate (SDS) from aqueous dispersions of single-wall carbon nanotubes (SWCNTs). Based on a survey of various reagents, organic solvents emerged as the most effective at interrupting the SDS:SWCNT interaction without producing deleterious side reactions or causing precipitation of the surfactant. Specifically, treatment with acetone or acetonitrile allows for the facile isolation of SWCNTs with near complete removal of SDS through vacuum filtration, resulting in a 100x reduction in processing time. These findings were validated via quantitative analysis using thermogravimetric analysis, Raman spectroscopy, 4-point probe electrical measurement, and X-ray photoelectron spectroscopy. Subsequent thermal oxidation further enhances the purity of the reagent treated samples and yields bulk SWCNT samples with >95% carbonaceous purity. The proposed reagent treatment method thus demonstrates potential for large volume SWCNT processing.

Profile evolution for conformal atomic layer deposition over nanotopography.

The self-limiting reactions which distinguish atomic layer deposition (ALD) provide ultrathin film deposition with superb conformality over the most challenging topography. This work addresses how the shapes (i.e., surface profiles) of nanostructures are modified by the conformality of ALD. As a nanostructure template, we employ a highly scalloped surface formed during the first anodization of the porous anodic alumina (PAA) process, followed by removal of the alumina to expose a scalloped Al surface. SEM and AFM reveal evolution of surface profiles that change with ALD layer thickness, influenced by the way ALD conformality decorates the underlying topography. The evolution of surface profiles is modeled using a simple geometric 3D extrusion model, which replicates the measured complex surface topography. Excellent agreement is obtained between experimental data and the results from this model, suggesting that for this ALD system conformality is very high even on highly structured, sharp features of the initial template surface. Through modeling and experimentation, the benefits of ALD to manipulate complex surface topographies are recognized and will play an important role in the design and nanofabrication of next generation devices with increasingly high aspect ratios as well as nanoscale features.