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We derive higher-order macroscopic transport models for semiconductor device simulation from Boltzmann’s transport equation using the method of moments. To obtain a tractable equation set suitable for numerical implementation the validity of the diffusion limit will be assumed which removes the convective terms from the equation system. The infinite hierarchy of equations is then truncated at the orders two (drift-diffusion model), four (energy-transport model), and six. Nonparabolicity correction factors are included in the streaming terms. Closure relations for the highest-order moments are obtained from a cold Maxwell distribution (drift-diffusion) and a heated Maxwell distribution (energy-transport). For the six moments model this issue is more complicated. In particular, this closure relation is identified to be crucial both in terms of accuracy and in terms of numerical stability. Various possible closure relations are discussed and compared. In addition to the closure of the highest-order moment, various transport parameters such as mobilities and relaxation times appear in the models and need to be accurately modeled. Particularly for higher-order transport models this is a complicated issue and since the analytical models used in our previous attempts did not deliver satisfactory results we extract all these parameters using homogeneous Monte Carlo simulations. Since all macroscopic transport models are based on rather stringent assumptions a practical evaluation is mandatory. Therefore, the proposed six moments model, a corresponding energy-transport model, and the drift-diffusion model are carefully compared to self-consistent Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

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The declining number of physician scientists is an alarming issue. A systematic review of all existing programs described in the literature was performed, so as to highlight which programs may serve as the best models for the training of successful physician scientists. Multiple databases were searched, and 1,294 articles related to physician scientist training were identified. Preference was given to studies that looked at number of confirmed publications and/or research grants as primary outcomes. Thirteen programs were identified in nine studies. Eighty-three percent of Medical Scientist Training Program (MSTP) graduates, 77% of Clinician Investigator Training Program (CI) graduates, and only 16% of Medical Fellows Program graduates entered a career in academics. Seventy-eight percent of MSTP graduates succeeded in obtaining National Institute of Health (NIH) grants, while only 15% of Mayo Clinic National Research Service Award-T32 graduates obtained NIH grants. MSTP physician scientists who graduated in 1990 had 13.5 ± 12.5 publications, while MSTP physician scientists who graduated in 1975 had 51.2 ± 38.3 publications. Additionally, graduates from the Mayo Clinic's MD-PhD Program, the CI Program, and the NSRA Program had 18.2 ± 20.1, 26.5 ± 24.5, and 17.9 ± 26.3 publications, respectively. MSTP is a successful model for the training of physician scientists in the United States, but training at the postgraduate level also shows promising outcomes. An increase in the number of positions available for training at the postgraduate level should be considered. [ABSTRACT FROM AUTHOR]

Medical schools in Taiwan have recently adopted the U.S. medical school admissions model by incorporating interviews into the selection process. The objective of this study was to investigate factors that contribute to successful medical school applications through the national entrance examination and interview admission routes. The sample consisted of survey data from five entry cohorts of medical students admitted to the National Yang-Ming University Faculty of Medicine from 2003 to 2007. Of the 513 students, 62% were admitted through the traditional national entrance examination route and 38% were admitted early after achieving a threshold score on the composite national exam followed by a structured interview. Students admitted through the interview route were more likely to be female, with an odds ratio (OR) of 2.17 (1.20-3.93). Maternal education level was an independent predictor of both early admission through a successful interview and higher medical school grade point average (GPA). Students admitted through the interview route had a 3.20 point higher first-year medical school GPA (p < .001) as determined by regression analyses. Those students who were admitted via interview did not have significantly different personality traits than those admitted through the traditional route. This study calls into question the ability of an admissions interview to select for noncognitive character traits. [ABSTRACT FROM AUTHOR]

Quantum electronics has significantly evolved over the last decades. Where initially the clear focus was on light-matter interactions, nowadays approaches based on the electron's wave nature have solidified themselves as additional focus areas. This development is largely driven by continuous advances in electron quantum optics, electron based quantum information processing, electronic materials, and nanoelectronic devices and systems. The pace of research in all of these areas is astonishing and is accompanied by substantial theoretical and experimental advancements. What is particularly exciting is the fact that the computational methods, together with broadly available large-scale computing resources, have matured to such a degree so as to be essential enabling technologies themselves. These methods allow to predict, analyze, and design not only individual physical processes but also entire devices and systems, which would otherwise be very challenging or sometimes even out of reach with conventional experimental capabilities. This review is thus a testament to the increasingly towering importance of computational methods for advancing the expanding field of quantum electronics. To that end, computational aspects of a representative selection of recent research in quantum electronics are highlighted where a major focus is on the electron's wave nature. By categorizing the research into concrete technological applications, researchers and engineers will be able to use this review as a source for inspiration regarding problem-specific computational methods., (Creative Commons Attribution license.)

The interaction between ASA and H.p. as the strongest irritants to gastric mucosa has not been sufficiently documented to date. The aim of our study was to evaluate the frequency of mucosal lesions in stomach and duodenum and the frequency of H.p. infection in patients suffering from IHD and chronically taking ASA. We evaluated the number of mucosal lesions and the incidence rate in relation to the daily dose of ASA. We examined 96 with IHD treated with ASA in doses: 75, 150 or 300 mg per day. We assessed the number of mucosal lesions and H.p. status. The control groups included 80 patients treated for IHD who did not take ASA and 50 patients who did not suffer from IHD. The highest rate of mucosal lesions we found in the group of patients with IHD treated with ASA: 62% vs 41% in patients not using ASA and 8% in the control group. We did not find any essential difference in mucosal lesions occurrence between patients treated with 75 or 150 and 300 mg per day. In patients with IHD using ASA the frequency of H.p. infection was higher in comparison to patients not receiving ASA (68% vs 47%) and to control group (68% vs 26%). ASA users infected with H.p. had more mucosal lesions (75%) in comparison to those not using ASA (47%). Our results confirm the synergistic harmful influence of ASA and H.p. infection on gastric and duodenal mucosa. It seems to us that the frequency of mucosal lesions development does not depend on the daily dose of ASA.