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In micro electro discharge machining (EDM), single pulse energy of pulsed power supply needs to be limited to a micro order of magnitude. One developing direction is to reduce the discharge pulse width for increasing discharging frequency. In order to research on micro EDM with nanometer gaps and nanometer removing units, a novel pulsed power supply with nanosecond pulse width was developed based on triode avalanche principle. The basic electric circuit with a steepening electric circuit was designed for the nanosecond pulse width. The test results show that the discharge pulses with an adjustable peak voltage and a pulse width down to 18 ns can be obtained. The developed pulsed power supply can output a single pulse and continuous pulses under high frequency.

The care of major trauma patients continues to be a challenge for emergency physicians and trauma surgeons. We found that the total number of radiological examinations for major trauma patients in this study was high and mainly comprised radiography and computed tomography (CT), with CT being more commonly adopted. The number of CT scans was positively correlated with severity of injury and intensive care unit length of stay. Further study is warranted to optimize radiological examinations involving major trauma patients.

Self-organized ZrO2 nanotubes are prepared via the conventional anodization method. Back-gate field effect transistors are fabricated for the first time to study the electrical transport properties of single ZrO2 nanotube The drain current increases with the applied negative gate voltage, which is suggesting the ZrO2 nanotube works under hole accumulation mode. The room temperature hole mobility of 0.03 cm2 V-1s[?]1 and average hole concentration of 2.8 x 1018 cm[?]3 are obtained at low drain bias. Temperature dependent I-V characteristics show that the hole concentration and hole mobility have an opposite changing trend with the temperature. The current of the device is controlled by the offset effect between the hole concentration and hole mobility.