Letters between A. M. Ten Eyck and W. J. Kerr

Letters concerning recommendation for position in Domestic Science at Utah Agricultural College

Double quantum dot with tunable coupling in an enhancement-mode silicon metal-oxide semiconductor device with lateral geometry

We present transport measurements of a tunable silicon metal-oxide-semiconductor double quantum dot device with lateral geometry. Experimentally extracted gate-to-dot capacitances show that the device is largely symmetric under the gate voltages applied. Intriguingly, these gate voltages themselves are not symmetric. Comparison with numerical simulations indicates that the applied gate voltages serve to offset an intrinsic asymmetry in the physical device. We also show a transition from a large single dot to two well isolated coupled dots, where the central gate of the device is used to controllably tune the interdot coupling.Comment: 4 pages, 3 figures, to be published in Applied Physics Letter

Prevalence of diabetes, metabolic syndrome and metabolic abnormalities in schizophrenia over the course of the illness: a cross-sectional study

BACKGROUND: Patients with schizophrenia are at high risk of developing metabolic abnormalities. METHOD: A prospective study focusing on metabolic disturbances in patients with schizophrenia, including an oral glucose tolerance test, is currently ongoing at our University Hospital and affiliate services. The prevalence of metabolic abnormalities at baseline was assessed in a cohort of 415 patients with schizophrenia. The sample was divided into 4 groups according to duration of illness: first-episode patients (<1.5 years), recent-onset patients (between 1.5 and 10 years), subchronic patients (between 10 and 20 years) and chronic patients (>20 years). RESULTS: Metabolic abnormalities were already present in first-episode patients, and considerably increased with increasing duration of illness. When compared to the general population matched for age and gender, much higher rates of the metabolic syndrome (MetS) and diabetes were observed for patients with schizophrenia. For MetS, the increase over time was similar to that of the general population. In contrast, the difference in the prevalence of diabetes in patients with schizophrenia and the general population dramatically and linearly increased from 1.6% in the 15–25 age-band to 19.2% in the 55–65 age-band. CONCLUSION: Thus, the current data suggest that on the one hand metabolic abnormalities are an inherent part of schizophrenic illness, as they are already present in first-episode patients. On the other hand, however, our results suggest a direct effect of the illness and/or antipsychotic medication on their occurence. The data underscore the need for screening for metabolic abnormalities in patients diagnosed with schizophrenia, already starting from the onset of the illness

Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications

Fabrication development work was carried out on a push-rod tip having a stepped OD design and a 90[degree] shoulder in the transition area. Spray-dried Sialon premix was used in dry press tooling, and components were densified to about 98% of theoretical density using pressureless sintering conditions. Upon evaluation of the sintered components, it was found that afl components showed defects in the transition area. Modifications of the pressing parameters, incorporation of a 45[degree] angle in the shoulder area, and the use of tailored premix did not lead to the fabrication of defect-free parts. From these observations, it was concluded that the original part design could not easily be adapted to high-volume ceramic manufacturing methods. Subsequently, a modification to the desip was implemented. An SiC material with improved toughness (Hexoloy SX) was used for fabricating several test components with a closely machined, straight OD design. Pressureless-sintered and post-hot isostatically pressed (HIPed) Hexoloy SX components were supplied to The American Ceramic Engine Company (ACE) for assembly and testing. Fuel pump push-rod assemblies with Hemoloy SX tips were prepared by ACE, but no testing has been carried out to date