Summary

Perchlorinated polysilanes were synthesized by polymerization of tetrachlorosilane under cold plasma conditions with hydrogen as a reducing agent. Subsequent selective cleavage of the resulting polymer yielded oligochlorosilanes SinCl2 n +2 (n = 2, 3) from which the octachlorotrisilane (n = 3, Cl8Si3, OCTS) was used as a novel precursor for the synthesis of single-crystalline Si nanowires (NW) by the well-established vapor–liquid–solid (VLS) mechanism. By adding doping agents, specifically BBr3 and PCl3, we achieved highly p- and n-type doped Si-NWs by means of atmospheric-pressure chemical vapor deposition (APCVD). These as grown NWs were investigated by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as electrical measurements of the NWs integrated in four-terminal and back-gated MOSFET modules. The intrinsic NWs appeared to be highly crystalline, with a preferred growth direction of [111] and a specific resistivity of ρ = 6 kΩ·cm. The doped NWs appeared to be [112] oriented with a specific resistivity of ρ = 198 mΩ·cm for p-type Si-NWs and ρ = 2.7 mΩ·cm for n-doped Si-NWs, revealing excellent dopant activation.

Aminoglycosides are commonly prescribed antibiotics with deleterious side effects to the inner ear. Due to their popular application as a result of their potent antimicrobial activities, many efforts have been undertaken to prevent aminoglycoside ototoxicity. Over the years, understanding of the antimicrobial as well as ototoxic mechanisms of aminoglycosides has increased. These mechanisms are reviewed in regard to established and potential future targets of hair cell protection.

Regional fat distribution is an important risk factor for the development of diabetes and hypertension in white females; those with fat cells in the upper part of the body have a higher prevalence of diabetes and hypertension than those with similar degrees of obesity in the lower parts of the body. Whether this observation is relevant for the general population of black females is not known. In this article, we report the results of a study of fat distribution in black females and its correlation with the prevalence of diabetes and hypertension. One hundred black females who attend the Charity Hospital System of Louisiana were studied. Anthropometric measurements were taken, and the prevalence of both diabetes and hypertension determined by review of the medical record and patient interview. In this study, the waist to hips ratio was the index of fat distribution. Waist to hips ratio was found to increase with age. The observed prevalence of diabetes, hypertension, and both together was higher in those with upper body obesity: 40% of those in the lower quartile had diabetes, whereas 80% of those in the highest quartile had diabetes. The mean waist to hips of diabetic patients (0.95) was higher than the ratio for nondiabetics (0.90). Hypertensives also had a higher ratio (0.95) than nonhypertensives (0.89). This is the first study to show that waist to hips ratio in blacks correlates with the prevalence of diabetes and hypertension. This suggests that the measurement of waist to hips ratio is an important part of the physical evaluation and may be a predictor of morbidity.(ABSTRACT TRUNCATED AT 250 WORDS)