338 research outputs found
Fabrication of minority-carrier-limited n-Si/insulator/metal diodes
Get PDFA photoelectrochemical anodization technique has been used to fabricate n-Si/insulator/metal (MIS) diodes with improved electrical properties. MIS structures fabricated with Au have provided the first experimental observation of a solid-state n-Si surface barrier device whose open circuit voltage Voc is controlled by minority-carrier bulk diffusion/recombination processes. For these diodes, variation of the minority-carrier diffusion length and majority-carrier dopant density produced changes in Voc that were in accord with bulk diffusion/recombination theory. Additionally, the variation in Voc in response to changes in the work function of the metal overlayer indicated that these MIS devices were not subject to the Fermi level pinning restrictions observed for n-Si Schottky structures. X-ray photoelectron spectroscopic characterization of the anodically grown insulator indicated 8.2±0.9 Å of a strained SiO2 layer as the interfacial insulator resulting from the photoanodization process
Inspiral, merger and ringdown of unequal mass black hole binaries: a multipolar analysis
Get PDFWe study the inspiral, merger and ringdown of unequal mass black hole
binaries by analyzing a catalogue of numerical simulations for seven different
values of the mass ratio (from q=M2/M1=1 to q=4). We compare numerical and
Post-Newtonian results by projecting the waveforms onto spin-weighted spherical
harmonics, characterized by angular indices (l,m). We find that the
Post-Newtonian equations predict remarkably well the relation between the wave
amplitude and the orbital frequency for each (l,m), and that the convergence of
the Post-Newtonian series to the numerical results is non-monotonic. To leading
order the total energy emitted in the merger phase scales like eta^2 and the
spin of the final black hole scales like eta, where eta=q/(1+q)^2 is the
symmetric mass ratio. We study the multipolar distribution of the radiation,
finding that odd-l multipoles are suppressed in the equal mass limit. Higher
multipoles carry a larger fraction of the total energy as q increases. We
introduce and compare three different definitions for the ringdown starting
time. Applying linear estimation methods (the so-called Prony methods) to the
ringdown phase, we find resolution-dependent time variations in the fitted
parameters of the final black hole. By cross-correlating information from
different multipoles we show that ringdown fits can be used to obtain precise
estimates of the mass and spin of the final black hole, which are in remarkable
agreement with energy and angular momentum balance calculations.Comment: 51 pages, 28 figures, 16 tables. Many improvements throughout the
text in response to the referee report. The calculation of multipolar
components in Appendix A now uses slightly different conventions. Matches
version in press in PR
Effectiveness of Health Education Teachers and School Nurses Teaching Sexually Transmitted Infections/ Human Immunodeficiency Virus Prevention Knowledge and Skills in High School
Get PDFBACKGROUND- We examined the differential impact of a well-established human immunodeficiency virus (HIV)/sexually transmitted infections (STIs) curriculum, Be Proud! Be Responsible!, when taught by school nurses and health education classroom teachers within a high school curricula.
METHODS- Group-randomized intervention study of 1357 ninth and tenth grade students in 10 schools. Twenty-seven facilitators (6 nurses, 21 teachers) provided programming; nurse-led classrooms were randomly assigned.
RESULTS- Students taught by teachers were more likely to report their instructor to be prepared, comfortable with the material, and challenged them to think about their health than students taught by a school nurse. Both groups reported significant improvements in HIV/STI/condom knowledge immediately following the intervention, compared to controls. Yet, those taught by school nurses reported significant and sustained changes (up to 12 months after intervention) in attitudes, beliefs, and efficacy, whereas those taught by health education teachers reported far fewer changes, with sustained improvement in condom knowledge only.
CONCLUSIONS- Both classroom teachers and school nurses are effective in conveying reproductive health information to high school students; however, teaching the technical (eg, condom use) and interpersonal (eg, negotiation) skills needed to reduce high-risk sexual behavior may require a unique set of skills and experiences that health education teachers may not typically have
Statistical Communication Theory
Get PDFContains research objectives and reports on six research projects
Health Professions Students\u27 Attitudes Toward Teamwork Before and After an Interprofessional Education Co-Curricular Experience
Get PDFBackground: Effective interprofessional collaboration may positively impact clinical outcomes, patient satisfaction, and cost effectiveness. However, educational silos and discipline-specific socialization have reinforced each health profession’s independent values, attitudes, and problem-solving approaches.
Methods and Findings: Students’ (N = 376) attitudes about teamwork were measured with the Interprofessional Attitudes Scale, Teamwork, Roles, and Responsibilities subscale using a pretest-posttest design. Experiential learning strategies and a case study approach were used to introduce students to the roles and responsibilities of the students’ disciplines. There was a positive mean difference in pretest-posttest measures (p \u3c .001) with a moderate effect size (r = .27).
Conclusions: Providing opportunities for pre-licensure health sciences students to understand the roles and responsibilities of other disciplines through IPE co-curricular learning can enhance positive attitudes toward teamwork
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