46 research outputs found
Thermionic charge transport in CMOS nano-transistors
We report on DC and microwave electrical transport measurements in
silicon-on-insulator CMOS nano-transistors at low and room temperature. At low
source-drain voltage, the DC current and RF response show signs of conductance
quantization. We attribute this to Coulomb blockade resulting from barriers
formed at the spacer-gate interfaces. We show that at high bias transport
occurs thermionically over the highest barrier: Transconductance traces
obtained from microwave scattering-parameter measurements at liquid helium and
room temperature is accurately fitted by a thermionic model. From the fits we
deduce the ratio of gate capacitance and quantum capacitance, as well as the
electron temperature
Effect of sterilization on osteoinduction. Comparison of five methods in demineralized rat bone.
The aim of this study was to find a safe, effective sterilization method that does not destroy the bone-inductive capacity of demineralized bone implants. Five sterilizing agents were tested in rats. Implants procured and processed under sterile conditions served as controls. New bone formation was evaluated by determining dry weight, calcium content, and Sr-85 incorporation of the induced ossicles. Glutaraldehyde solution, formaldehyde gas, and ethylene oxide destroyed almost all the bone-inductive capacity. Irradiation by 2.5 Mrads Co-60 resulted in a loss of about half of the inductive capacity. Merthiolate (0.18 per cent) was the only sterilizing agent that did not reduce the bone-inductive capacity of the demineralized implants. Because merthiolate is not sporicidal, gamma irradiation appears to be the most appropriate sterilizing agent for demineralized bone in clinical use
Long-term results and late recurrence after endoureteropyelotomy: a critical analysis of prognostic factors.
Of 102 consecutive endoureteropyelotomy cases followed for 1 to 10 years (mean 5) late recurrence was observed in 13% and long-term success was achieved in 73%. Of 67 cases with an available preoperative angiogram a strong association was noted between the existence of a vessel crossing the ureteropelvic junction and high grade hydronephrosis, and final failure and/or recurrence: long-term success rate was 39% when both factors were present and it was 95% when neither factor was present. Therefore, we recommend that the presence of a vessel should be determined preoperatively since it significantly influences the outcome