Engineering the Electron-Hole Bilayer Tunneling Field-Effect Transistor

The electron-hole (EH) bilayer tunneling field-effect transistor promises to eliminate heavy-doping band tails enabling a smaller subthreshold swing voltage. Nevertheless, the electrostatics of a thin structure must be optimized for gate efficiency. We analyze the tradeoff between gate efficiency versus ON-state conductance to find the optimal device design. Once the EH bilayer is optimized for a given ON-state conductance, Si, Ge, and InAs all have similar gate efficiency, around 40%-50%. Unlike Si and Ge, only the InAs case allows a manageable work function difference for EH bilayer transistor operation.National Science Foundation (U.S.). Center for Energy Efficient Electronics Science (Award 0939514

Machine detector interface for the e+e−e^+e^- future circular collider

The international Future Circular Collider (FCC) study aims at a design of $pp$, $e^+e^-$, $ep$ colliders to be built in a new 100 km tunnel in the Geneva region. The $e^+e^-$ collider (FCC-ee) has a centre of mass energy range between 90 (Z-pole) and 375 GeV (tt_bar). To reach such unprecedented energies and luminosities, the design of the interaction region is crucial. The crab-waist collision scheme has been chosen for the design and it will be compatible with all beam energies. In this paper we will describe the machine detector interface layout including the solenoid compensation scheme. We will describe how this layout fulfills all the requirements set by the parameters table and by the physical constraints. We will summarize the studies of the impact of the synchrotron radiation, the analysis of trapped modes and of the backgrounds induced by single beam and luminosity effects giving an estimate of the losses in the interaction region and in the detector.Comment: 6 pages, 7 figures, 62th ICFA ABDW on High Luminosity Circular $e^+e^-$ Colliders, eeFACT2018, Hong Kong, Chin

Medical Students’ Use of the Stages of Change Model in Tobacco Cessation Counseling

BACKGROUND: Many medical schools have incorporated the Stages of Change Model into their curricula with specific application to tobacco cessation. OBJECTIVE: This study examined the extent to which medical students were prepared to provide stage-based interventions to treat nicotine dependence. DESIGN: Using a quasi-experimental design, medical students’ counseling interactions were evaluated with a standardized patient portraying a smoker in either the precontemplation or preparation stage of change. PARTICIPANTS: Participants were 147 third-year medical students at the University of California, San Francisco. MEASUREMENTS: Checklists completed by standardized patients evaluated students’ clinical performance. Surveys administered before and after the encounters assessed students’ knowledge, attitudes, confidence and previous experience with treating smoking. RESULTS: Most students asked about tobacco use (89%), advised patients of the health benefits of quitting (74%), and assessed the patient’s readiness to quit (76%). The students were more likely to prescribe medications and offer referrals to patients in the preparation than in the precontemplation stage of change (P < 0.001); however, many students had difficulty identifying patients ready to quit, and few encouraged patients to set a quit date or arranged follow-up to assess progress. Students’ tobacco-related knowledge, but not their attitudes, confidence, or previous experience predicted their clinical performance. CONCLUSIONS: The findings indicated evidence of students tailoring their counseling strategies to the patients’ stage of change; however, they still could do more to assist their patients in quitting. Additional training and integration of cessation counseling into clinical rotations are needed

Benefits and barriers among volunteer teaching faculty: comparison between those who precept and those who do not in the core pediatrics clerkship

Background: Community-based outpatient experiences are a core component of the clinical years in medical school. Central to the success of this experience is the recruitment and retention of volunteer faculty from the community. Prior studies have identified reasons why some preceptors volunteer their time however, there is a paucity of data comparing those who volunteer from those who do not. Methods: A survey was developed following a review of previous studies addressing perceptions of community-based preceptors. A non-parametric, Mann&#x2013;Whitney U test was used to compare active preceptors (APs) and inactive preceptors (IPs) and all data were analyzed in SPSS 20.0. Results: There was a 28% response rate. Preceptors showed similar demographic characteristics, valued intrinsic over extrinsic benefits, and appreciated Continuing Medical Education (CME)/Maintenance of Certification (MOC) opportunities as the highest extrinsic reward. APs were more likely to also precept at the M1/M2 level and value recognition and faculty development opportunities (p&#x3C;0.05). IPs denoted time as the most significant barrier and, in comparison to APs, rated financial compensation as more important (p&#x3C;0.05). Conclusions: Community preceptors are motivated by intrinsic benefits of teaching. Efforts to recruit should initially focus on promoting awareness of teaching opportunities and offering CME/MOC opportunities. Increasing the pool of preceptors may require financial compensation

Band-to-band tunneling in silicon diodes and tunnel transistors

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student submitted PDF version of thesis.Includes bibliographical references (p. 82-83).This work studies the effect of mechanically applied uniaxial strain on reverse-bias band-to-band tunneling current in n+/p+ vertical silicon diodes fabricated on {100} and {110} substrate orientations. The Band Structure Lab and nextnano are used to analyze the change in band structure with uniaxial stress applied perpendicular to the tunneling direction along and crystal directions. A theoretical analysis based on the Wentzel-Kramers-Brillouin (WKB) approximation for tunneling probability combined with an uncoupled full-band Poisson equation solver and the calculated band structure changes is developed to model the experimental results. Reasonable agreement between experimental data and theoretical calculations is found when comparing the relative change in tunneling current at 1 V reverse-bias versus strain for different substrate orientation/strain configurations.by James Towfik Teherani.S.M

Clerkship Students’ Use of Clinical Reasoning Concepts After a Pre-clinical Reasoning Course

BackgroundMany medical schools have incorporated clinical reasoning (CR) courses into their pre-clinical curricula to address the quality and safety issue of diagnostic error. It is unknown how students use concepts and practices from pre-clinical CR courses once in clerkships.ObjectiveWe sought to understand how students utilize CR concepts from a pre-clinical course during clerkships and to identify facilitators and barriers to the use of reasoning concepts.DesignWe used structured interviews to gain insight into medical students' experiences with CR concepts in clerkships.ParticipantsWe interviewed 16 students who had completed a pre-clinical CR course and subsequently completed a neurology, internal medicine, or pediatrics clerkship.ApproachWe used constructivist grounded theory to perform a qualitative analysis and to develop a theoretical model to describe findings.Key resultsInsights fell into three main areas: (1) CR concept carryover, representing concepts taught in the CR course, such as problem representation, illness scripts, schema, and prioritized&nbsp;differential diagnosis, which were utilized in clerkships; (2) CR concept reinforcers, which included the clerkship setting and supervising physicians who emphasized and provided feedback on CR; and (3) CR concept diminishers, which included time constraints and supervisors who were unfamiliar with or did not reinforce CR concepts.ConclusionsConcepts taught in a pre-clinical CR course influenced how students prepared for and navigated clinical encounters. Contextual factors both enhanced and inhibited the utilization of CR concepts. Our findings align with social learning theories including social cognitive theory and ecological psychology. This contextual view-taking into account interactions between personal, social, and environmental factors-can help educators integrate CR education from the classroom to the clinical setting

Recherche des flavacoumarines par Chromatographie en couche mince. Importance de la discrimination des autres taches fluorescentes

Teherani A., Jacquet Jean, Boutibonnes Ph. Recherche des flavacoumarines par chromatographie en couche mince. Importance de la discrimination des autres taches fluorescentes. In: Bulletin de l'Académie Vétérinaire de France tome 124 n°6, 1971. pp. 263-275