UNLABELLED The study was performed to compare the (18)F-labeled nitroimidazole compound fluoroazomycin arabinoside ((18)F-FAZA) with the standard hypoxia tracer fluoromisonidazole ((18)F-FMISO) in detection of tumor tissue hypoxia and to verify the oxygenation dependency of (18)F-FAZA uptake. METHODS Biodistribution of (18)F-FAZA was studied at various time points in EMT6 tumor-bearing BALB/c...

A new approach to rejecting interference between sonar systems is presented in this paper. The approach is based on identifying a transmitter by sending a double pulse with known separation. Using simple delayed pulse subtraction, a sonar receiver can test echo pulses quickly and simply for acceptance. This approach is implemented on a sonar system that is capable of accurately tracking objects...

The patallar-tendon-bearing supracondy­ lar, suprapatellar air cushion (PTS-AC) below-knee (BK) prosthesis is a special modi­ fication of the supracondylar, suprapatellar suspension and the air cusion socket. The air cushion principle in combination with the patella tendon-bearing (PTB) prosthesis was introduced by Lyquist, Wilson, and Radcliffe (Fig. 1), (2) in 1965. It requires more accurate ...

Current trends in micro-turbomachinery stress the need for adequate rotordynamic models. These models should allow accurate prediction of critical speeds, imbalance response and stable operation range of microturbomachinery rotor-bearing systems. This paper gives an overview of the total rotordynamic modelling process of a micro-turbine rotor supported on aerostatic bearings. A both accurate an...

Oil-free microturbomachinery (MTM) are inevitably subjected to base or foundation excitations: passenger and commercial transportation vehicles experiencing intermittent excitation from road conditions, and (multiple) periodic load excitations from internal combustion (IC) engines in turbochargers, for example. Too large base excitations can produce severe damage, even failure, due to hard coll...

This study presents a developed hybrid electrical air-cushion tracked vehicle (HETAV) for the transportation operation of agricultural and industrial goods on the swamp peat terrain bearing capacity of 5 kN/m. The vehicle’s design parameters are optimized by using the developed mathematical models which are made based on the kinematics and dynamics behaviors of the vehicle. A set of sensors are...

A technique to analyze particulates extracted from inline jet engine oil filters using energy dispersive X-ray fluorescence (EDXRF) is presented. This technique, developed by the U.S. Department of Defense’s Joint Oil Analysis Technical Support Center (JOAP-TSC), is termed filter debris analysis (FDA). Six beta prototype instruments capable of performing FDA-EDXRF in an automated mode were manu...

Synchronous Thermal Instability Evaluation of Medium Speed Turbocharger Rotor-Bearing Systems Brian R. Carroll Rotors in fluid-film bearing supported turbomachinery are known to develop elliptical orbits as a result of rotor-bearing interactions, mass unbalance within the rotor, gravitational bending of the shaft and external excitation. In synchronous whirl, where the speed at which the shaft ...

Lubrication with ambient air is not quite generally applied. The best known application is the “foil bearing” in tape recording systems for audio, video and computer applications; where the gap height that is needed for effective lubrication may quite easily be attained. This air gap reduces tape friction and wear of tape and recording head substantially. On the other hand, though, the air gap ...