Bioengineering

Quantitative Digital Rectal Examination

We are developing a device for the quantitative and objective assessment of the health of the prostate during the digital rectal examination (DRE). The output of the device is contour maps that can be portrayed on a computer screen and stored electronically for future reference. Such quantitative data can help the physician make an accurate diagnosis about the stage of the disease and recommend an optimal strategy for patient care.

Burn Injury from Fabric Fires

For NBS, we performed an evaluation of the burn injury potential of clothing fires. Fire tests were conducted on fabric strips next to a skin simulant and on garments over mannequins. Heat transfer to skin simulant and mannequins was measured and used to indicate burn areas, degrees and mechanisms. We integrated the results to assess the influence of fabric materials and garment designs.

Effects of Microwave Energy on Birds

For EPA, we investigated the thermal response of birds to microwave (2.5GHz) transmission from a satellite power system. Birds were irradiated (to 50 mW/sq.cm) in anechoic chambers under limited conditions. We used a model to extend the results to a range of air temperature, relative humidity, solar loading and wind speed.

Thermal Response of Cells to Heat

For NIH, we studied the effects of heat in Hela S-3 cells. In a unique microscope system, cells were subjected to well-defined heating and cooling protocols. Cell damage was measured and modeled using the concepts of Henrique's damage integral. This delineated the effect of temperature and its rate of rise.

In similar tests on erythrocytes, we measured hemolysis as a function of time and temperature. Two models successfully correlated the data -- a kinetic scheme with a reversible reaction followed by an irreversible one; and a statistical model with bell-shaped cell sensitivity. The later model provided a superior data fit while the former offered other advantages.