Self‐consistent scattering matrix calculation of the distribution function in semiconductor devices

The scattering matrix approach is a new technique for solving the Boltzmann equation in devices. We report a self-consistent application of the technique to realistic silicon devices exhibiting strong nonlocal effects. Simulation of a hot-electron, n-i-n diode demonstrates that the new technique efficiently and accurately reproduces Monte Carlo results without the statistical noise, allowing much tighter convergence with Poisson’s equation

A Spectral Flux Method for Solving the Boltzmann Equation

A spectral method for solving the Boltzmann equation by the scattering matrix approach is presented, The algorithm discussed can be used to simulate both bulk and device properties with arbitrary field profiles. Although the primary goal is to reduce the data storage problem of the scattering matrix approach, many of the concepts and mathematical properties developed may be useful for other traditional spectral methods as well

A first update on mapping the human genetic architecture of COVID-19

peer reviewe

Evaluation of Factors Related to Glycemic Management in Professional Cyclists With Type 1 Diabetes Over a 7-Day Stage Race

OBJECTIVE To investigate factors related to glycemic management among members of a professional cycling team with type 1 diabetes over a 7-day Union Cycliste Internationale World Tour stage race.RESEARCH DESIGN AND METHODS An observational evaluation of possible factors related to glycemic management and performance in six male professional cyclists with type 1 diabetes (HbA1c 6.4 ± 0.6%) during the 2019 Tour of California.RESULTS In-ride time spent in euglycemia (3.9–10.0 mmol/L glucose) was 63 ± 11%, with a low percentage of time spent in level 1 (3.0–3.9 mmol/L; 0 ± 1% of time) and level 2 (13.9 mmol/L) hyperglycemia during races. Bolus insulin use was uncommon during races, despite high carbohydrate intake (76 ± 23 g ⋅ h−1). Overnight, the riders spent progressively more time in hypoglycemia from day 1 (6 ± 12% in level 1 and 0 ± 0% in level 2) to day 7 (12 ± 12% in level 1 and 2 ± 4% in level 2) (χ2[1] > 4.78, P < 0.05).CONCLUSIONS Professional cyclists with type 1 diabetes have excellent in-race glycemia, but significant hypoglycemia during recovery overnight, throughout a 7-day stage race

Particle emission characteristics of a gas turbine with a double annular combustor

The total climate, air quality, and health impact of aircraft black carbon (BC) emissions depend on quantity (mass and number concentration) as well as morphology (fractal dimension and surface area) of emitted BC aggregates. This study examines multiple BC emission metrics from a gas turbine with a double annular combustor, CFM56-5B4-2P. As a part of the SAMPLE III.2 campaign, concurrent measurements of particle mobility, particle mass, particle number concentration, and mass concentration, as well as collection of transmission electron microscopy (TEM) samples, allowed for characterization of the BC emissions. Mass- and number-based emission indices were strongly influenced by thrust setting during pilot combustion and ranged from <1 to 208 mg/kg-fuel and 3 ×× 1012 to 3 ×× 1016 particles/kg-fuel, respectively. Mobility measurements indicated that mean diameters ranged from 7 to 44 nm with a strong dependence on thrust during pilot-only combustion. Using aggregation and sintering theory with empirical effective density relationships, a power-law relationship between primary particle diameter and mobility diameter is presented. Mean primary particle diameter ranged from 6 to 19 nm; however, laser-induced incandescence (LII) and mass-mobility-calculated primary particle diameters demonstrated opposite trends with thrust setting. Similarly, mass-mobility-calculated aggregate mass specific surface area and LII-measured surface area were not in agreement, indicating both methods need further development and validation before use as quantitative indicators of primary particle diameter and mass-specific surface area

Newly designed field control module for the SNS

The low-level RF (LLRF) control system for the Spallation Neutron Source has undergone some recent hardware changes. The intended Field and Resonance Control Module (FRCM) design has been re-vamped to minimize functionality and ease implementation. This effort spans a variety of disciplines, and requires parallel development with distinct interface controls. This paper will discuss the platform chosen, the design requirements that will be met, and the parallel development efforts ongoing

Drug-eluting stents: a study of international practice.

OBJECTIVE: We aimed to analyze trends in drug-eluting stents (DES) use in four international health care and regulatory settings. BACKGROUND: Accounts suggest a differential approach to DES internationally and recent reductions in use following reports of late stent thrombosis. Current studies of clinical practice are limited in their scope. METHODS: Data were pooled from angioplasty registries in Alberta (Canada), Belgium, Mayo Clinic (Rochester, MN), and Scotland (UK) that have routinely recorded consecutive patients treated since 2003. Trend analysis was performed to examine variations in DES use over time and by clinical subgroup. RESULTS: A total of 178,504 lesions treated between January 2003 and September 2007 were included. In the Mayo Clinic Registry, rapid adoption to a peak of 91% DES use for all lesions by late 2004 was observed. In contrast, Alberta and Scotland showed delayed adoption with lower peak DES use, respectively, 56% and 58% of lesions by early 2006. Adoption of DES in Belgium was more gradual and peak use of 35% lower than other registries. Reductions in DES use were seen in all data sets during 2006, although this varied in absolute and relative terms and by clinical subgroup. CONCLUSION: Adoption and use of DES showed wide variation in four countries. The determinants of use are complex, and it is likely that nonclinical factors predominate. Recent reductions in use may be as a consequence of publicity and concerns regarding late stent thrombosis. The optimum application of DES in clinical practice is unclear and is reflected in the degree of international variation demonstrated