Long-term effect of inducible silent ischaemia on left ventricular systolic function

A new method of thin section preparation of III-V semiconductors and multilayers for transmission electron microscopy (TEM) is presented that exhibits considerable advantages over conventional methods such as ion beam milling and jet thinning. GaAs thin films and multilayers of GaAs/In chi Ga1-chi As/GaAs are grown over an etch release layer of AlAs on GaAs substrates by molecular beam epitaxy (MBE). Planar TEM sections prepared by selective etching from these samples show improved ability to image film morphology and dislocation arrangements, and the resulting large thin electron transparent areas facilitate dislocation density measurements and detection of spatial variations. Avoidance of radiation effects and wedge shaping, both common to ion milled samples, allows this method to be used to prepare uniform thickness standards of single layer GaAs films for EDS analysis or lattice imaging.     

Efficacy evaluation of a 4% chlorhexidine gluconate as a full-body shower wash

A 4% chlorhexidine gluconate (Xttrium Laboratories, Chicago, Ill.) was used in a shower bath application to evaluate its merits in reducing resident skin microorganisms. Five volunteers completed a 14-day microbial stabilization period, a 7-day baseline period, and a 5-day test period. Subjects followed a standard protocol, performed five shower washes and were sampled at both the abdominal and inguinal regions immediately after the shower wash as well as at 3 and 6 hours later on days 1, 2, and 5. Chlorhexidine gluconate provided significant microbial reductions from baseline, with greater reductions noted as the study progressed. Use of chlorhexidine gluconate in a shower wash application in conjunction with a preoperative skin-preparation procedure may reduce the probability of surgically associated infections.     

DSM-III-R personality disorders in a mood and anxiety disorders clinic: prevalence, comorbidity, and clinical correlates

This study examined the prevalence, comorbidity, and clinical correlates of personality disorders in an outpatient sample (N = 352) with anxiety and depression. Subjects were diagnosed using the Structured Clinical Interview for DSM-III-R (SCID) on Axes I and II, and they also completed interview and self-report measures of symptoms. Subjects with a personality disorder were less likely to be married, more likely to be single or divorced, had lower family incomes, had more severe symptoms of both anxiety and depression, and had a greater number of lifetime Axis I diagnoses. Subjects with dysthymic and bipolar disorders were more likely, and subjects with panic disorder uncomplicated by agoraphobia were less likely to have a personality disorder compared to the rest of the sample. The most prevalent personality disorders were Avoidant, Obsessive-Compulsive, Paranoid, and Borderline. Paranoid co-occurred with Narcissistic, and Borderline co-occurred with Histrionic personality disorder significantly more often than chance and base rates would predict.     

Effect of prenatal alcohol and cigarette exposure on two- and six-month-old infants'' adrenocortical reactivity to stress

Biologic data on benzene metabolite doses, cytotoxicity, and genotoxicity often show that these effects do not vary directly with cumulative benzene exposure (i.e., concentration times time, or c x t). To examine the effect of an alternate exposure metric, we analyzed cell-type specific leukemia mortality in Pliofilm workers. The work history of each Pliofilm worker was used to define each worker's maximally exposed job/department combination over time and the associated long-term average concentration associated with the maximally exposed job (LTA-MEJ). Using this measure, in conjunction with four job exposure estimates, we calculated SMRs for groups of workers with increasing LTA-MEJs. The analyses suggest that a critical concentration of benzene exposure must be reached in order for the risk of leukemia or, more specifically, AMML to be expressed. The minimum concentration is between 20 and 60 ppm depending on the exposure estimate and endpoint (all leukemias or AMMLs only). We believe these analyses are a useful adjunct to previous analyses of the Pliofilm data. They suggests that (a) AMML risk is shown only above a critical concentration of benzene exposure, measured as a long-term average and experienced for years, (b) the critical concentration is between 50 and 60 ppm when using a median exposure estimate derived from three previous exposure assessments, and is between 20 and 25 ppm using the lowest exposure estimates, and (c) risks for total leukemia are driven by risks for AMML, suggesting that AMML is the cell type related to benzene exposure.     

High quality gate dielectrics formed by rapid thermal chemical vapor deposition of silane and nitrous oxide

In the present study, we have performed electrical characterization of oxides deposited via rapid thermal chemical vapor deposition using SiH₄ and N₂O. We have investigated the effect of temperature, pressure, and SiH₄ to N₂O ratio on the electrical and material properties of as-deposited films. We have found that as-deposited oxides deposited at low temperatures, low pressures, and with a low silane to nitrous oxide ratio of ～0.5% give good material and electrical properties. The as-deposited films are stoichiometric in nature and have high deposition rates. As-deposited films had very low D_it values, high breakdown fields, and excellent subthreshold swing. The leakage currents and metal oxide semiconductor field effect transistor current drive, although lower than thermal oxides, were found to be quite acceptable. We have also investigated the thickness dependence of the films and found that as the film thickness is reduced below 50Å, the reliability improves for all oxides including the silicon-rich deposited oxides.