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.

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.

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.

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.

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.