Metamorphic InAlAs/InGaAs HEMTs on GaAs substrates with a novelcomposite channels design

We report on fabrication and performance of novel 0.13 μm T-gate metamorphic InAlAs/InGaAs HEMTs on GaAs substrates with composite InGaAs channels, combining the superior transport properties of In_0.52Ga_0.48As with low-impact ionization in the In_0.32Ga_0.68As subchannel. These devices exhibit excellent DC characteristics, high drain currents of 750 mA/mm, extrinsic transconductances of 600 mS/mm, combined with still very low output conductance values of 20 mS/mm, and high channel and gate breakdown voltages. The use of a composite InGaAs channels leads to excellent cut-off frequencies: f_max of 350 GHz and an f_T 160 GHz at V_DS=1.5 V. These are the best microwave frequency results ever reported for any FET on GaAs substrate     

Surveillance of non-fatal workplace assault injuries, using police and employers'' reports

BACKGROUND: There is a need to evaluate the effectiveness of laryngeal fracture repair using rigid adaptation plates. METHODS: A retrospective chart review of patients undergoing open repair of laryngeal fractures using metal alloy plates, from 1987 to 1995, was performed. Postoperative airway, deglutition, and voice were assessed. Postoperative follow-up ranged from 1 to 58 months (median, 27 months). All 10 patients sustained blunt or penetrating laryngeal trauma. After patients were resuscitated according to the ABC principles recommended by the American College of Surgeons, each underwent open repair of laryngeal fractures using rigid adaptation plates. RESULTS: Outcome was measured by perceptual analysis of the postoperative airway, swallowing, and voice, as well as biocompatibility. Ten patients underwent repair and stabilization of the larynx using adaptation plates. Nine patients sustained blunt trauma, and one patient sustained penetrating trauma. Voice was subjectively graded as good if it resembled the preinjury status, fair if it differed, and poor if it represented aphonia, whisper, or unintelligible speech. Airway was graded as good if it resembled preinjury status, fair if mild exercise intolerance or aspiration existed, and poor if the patient could not be decannulated. Nine patients had a good airway following repair, and six of seven patients requiring tracheotomy were decannulated. All patients tolerated the plates well and suffered no surgical complications. CONCLUSION: Repair of the laryngeal framework using adaptation plates provides adequate, immediate stabilization with restoration of function and is an alternative to traditional methods of repair.     

Tunneled hemodialysis catheters: use of a silver-coated catheter for prevention of infection--a randomized study

OBJECTIVE: The purpose of this study was to determine the feasibility of high-resolution sonography for the detection of meniscal cysts and associated meniscal tears and for the differentiation of meniscal cysts from other masses at the knee joint. SUBJECTS AND METHODS: Fifty consecutive patients (51 knees) with a palpable mass at the knee joint were examined prospectively using a 7.5-MHz annular array transducer. Mass consistency and location and meniscal integrity were evaluated. Sonographic findings were correlated with surgery (46/51) and histopathology (15/51). Five patients did not undergo surgery. RESULTS: At surgery, 32 masses appeared to be meniscal cysts, whereas 19 were other types of masses. Sonographically, 31 of the 32 meniscal cysts were diagnosed correctly. Sonographic differentiation of the other types of masses from meniscal cysts could reliably be made in 17 of 19 cases; two masses were falsely interpreted as meniscal cysts. Sensitivity, specificity, and accuracy of sonography in the depiction of meniscal cysts were 97%, 86%, and 94%, respectively. The positive predictive value was 94% and the negative predictive value was 92%. Meniscal tears (31/46) and meniscal tears concomitant with meniscal cysts (26/32) were detected with an accuracy of 83% and 88%, respectively. CONCLUSION: Sonography is an accurate imaging technique for the detection of meniscal cysts and associated meniscal tears. Differentiation of meniscal cysts from other cystic and solid masses at the knee joint can be reliably made with sonography.     

Coating the inner walls of metal tubes with carbon films by physical vapor deposition at low temperature

Tubes are often required to exhibit better performance in corrosion and wear behavior than the material the tube is made of can offer. The situation can be improved when the tube is coated with a protective film. This can be achieved by sputter coating with an ion beam. A sputter target is located inside the tube. Energetic ions are accelerated into the tube and impinge onto the target. Thus, material is sputtered from the target onto the inner walls of the tube. Two apparatus for coating tubes of different lengths and diameters are described. Aluminum and stainless steel tubes were coated with amorphous carbon films. Results on adhesion, corrosion performance in aqueous media and thickness uniformity are shown.     

A combined test used for the diagnosis of organic brain condition: Predictive validity based on radiographic and electroencephalographic criteria.

The predictions of "organic" brain damage made by A. A. Elizur's (see 34:4) Combined Test for the Diagnosis of Organic Brain Condition were validated against EEG and radiographic criteria from 231 neuropsychiatric patients. There was a highly significant correlation between the predictions and the criteria. The test predicted correctly 69% of the EEG findings, 71% of the radiographic findings, and 82% of the combined EEG and radiographic findings when the 2 were in agreement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bacterial hemagglutination by Neisseria gonorrhoeae

Direct bacterial hemagglutination was investigated with 20 clinical isolates of Neisseria gonorrhoeae. The hemagglutination tests were performed by both a macrotechnique with glass slides and a microtechnique with autotrays. Only organisms from form type 1 or 2 colonies caused hemagglutination. There was no statistical difference at a 10% or higher level in hemagglutination powers of type 1 and type 2 organisms, of male urethral and female cervical isolates, and of the eight major human blood types (ABO-Rh). Of seven erythrocyte species tested, only human cells were agglutinated. D-Mannose did not prevent the agglutination. Rabbit antigonococcal serum and high-titer antigonococcal human sera inhibited the hemagglutination. The results suggest the pili are the mediators of hemagglutination and that their specific agglutination of human erythrocytes may be a correlate of their adherence to human mucosal cells in natural infection. Also, although the procedure is presently insensitive, it is possible to detect human antigonococcal antibody by inhibition of direct bacterial hemagglutination.     

Enthalpy—pressure (H-p) diagram of He3 in the range 1.0 K ≤ T ≤ 4.17 K and 0 ≤ p ≤ 6.5 atm and inversion curve for T ≤ 4.17 K

The enthalpy-pressure (H-p) diagram of He³ was determined by experiment. All important data for the operation of a continuous He³ refrigerator working on the Joule-Thomson principle can be derived from this diagram. In particular, the achievable refrigerating capacity at preselected operating conditions may be immediately ascertained. The inversion curve of He³ for T ? 4.17 K was determined from the H-p diagram and is in fair agreement with the data for T ? 4 K already known.     

An analysis of bottom entry nozzles for atmospheric storage tanks

In this paper, we describe the analysis of soil settlement in the vicinity of a bottom entry nozzle of an atmospheric storage tank for several practical loadings. These are the pressure of the liquid stored in the tank, the body force of the rock and soil foundation, and an external moment applied to the nozzle where it emerges from the foundation. The foundation is modelled as a three-dimensional elastic medium which can support no tensile stress and is composed of two materials (rock and soil) with an elastic cylindrical shell embedded in the rock phase. The solution is accomplished with a general-purpose finite element program (ICES—STRUDL II). The overall conclusion reached is that bottom entry nozzles are acceptable for tankage installed on reasonably good soil.