The effect of pressure on the band-gap energy in ordered GaInP and AlGaInP grown by MOVPE

Photoluminescence (PL) measurements on Ga0.52In0.48P and Al0.18Ga0.34In0.48, P alloys, grown by metalorganic vapor phase epitaxy (MOVPE) on GaAs, have been made as a function of pressure up to about 4.5 GPa at 77 K. The substrates are oriented on the (100) and off the (100) plane toward [011] and [011¯] by up to 25°. The band-gap energy anomaly in the CuPt-type ordered structure has been systematically investigated at high pressures. With increasing pressure the E0 band gap shows a sublinear shift toward higher energies. For some samples, this shift tends to saturate, of the PL peak shows a decrease in energy with pressure. The pressures needed for these observations are found to be significantly smaller in AlGaInP than in GaInP. The observed behaviors strongly depend on substrate misorientation, and hence reflect the degree of ordering in these alloys. These results clearly demonstrate the importance of the effects of repulsion between the G-folded energy states on the optical spectra in the CuPt-type ordered structure. Possible explanations for some of the trends in high-pressure behavior of the E0 direct band gap in GaInP and AlGaInP samples having different degrees of ordering are discussed, including the modification of the ordinary G-X crossover upon ordering

Statusbericht zu Forschung und Anwendung der wirkmedienbasierten Blechumformung Neue Konzepte fuer die Herausforderung von morgen

Available from TIB Hannover: RR 7808(520) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

What’s around me? Spatialized audio augmented reality for blind users with a smartphone

Abstract. Numerous projects have investigated assistive navigation technologies for the blind community, tackling challenges ranging from interface design to sensory substitution. However, none of these have successfully integrated what we consider to be the three factors necessary for a widely deployable system that delivers a rich experience of one’s environment: implementation on a commodity device, use of a preexisting worldwide point of interest (POI) database, and a means of rendering the environment that is superior to a naive playback of spoken text. Our “In Situ Audio Services ” (ISAS) application responds to these needs, allowing users to explore an urban area without necessarily having a particular destination in mind. We describe the technical aspects of its implementation, user requirements, interface design, safety concerns, POI data source issues, and further requirements to make the system practical on a wider basis. Initial qualitative feedback from blind users is also discussed

Capacity Building in Female Pelvic Medicine and Reconstructive Surgery: Global Health Partnership Beyond Fistula Care in Ethiopia

Objective: Obstetric fistula is a devastating childbirth injury that leaves women incontinent, stigmatized and often isolated from their families and communities. In Ethiopia, although much attention has focused on treating and preventing obstetric fistula, other more prevalent childbirth-related pelvic floor disorders, such as pelvic organ prolapse, non-fistula-related incontinence and post-fistula residual incontinence, remain largely unattended. The lack of international and local attention to addressing devastating pelvic floor disorders is concerning for women in low- and middle-income countries. The objective of this article is to highlight the need for a more comprehsive approach to pelvic floor care and to share our experience in addressing it. Methods: Here, we share our experience launching one of the first formal training programs in Female Pelvic Medicine and Reconstructive Surgery (FPMRS) in Ethiopia. Results: This fellowship program provides quality care while strengthening the health system in its local context. This program has positioned Ethiopia to be a regional leader by providing comprehensive training of surgeons and allied health professionals, building appropriate health system and research infrastructure, and developing a formal FPMRS training curriculum. Conclusion: We hope that sharing this experience will serve as a template for others championing comprehensive pelvic floor care for women in low- and middle-income countries