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The performance of a 10 mm diameter pyroelectric detector coated with a single-wall carbon nanotube (SWCNT) was evaluated in the 0.8 to 20 [micro]m wavelength range. The relative spectral responsivity of this detector exhibits significant fluctuations over the wavelength range examined. This is consistent with independent absorbance measurements, which show that SWCNTs exhibit selective absorption bands in the visible and near-infrared. The performance of the detector in terms of noise equivalent power and detectivity in wavelength regions of high coating absorptivity was comparable with gold-black-coated pyroelectric detectors based on 50 [micro]m thick LiTa[O.sub.3] crystals. The response of this detector was shown to be nonlinear for DC equivalent photocurrents > [10.sup.-9] A, and its spatial uniformity of response was comparable with other pyroelectric detectors utilizing gold-black coatings. The nonuniform spectral responsivity exhibited by the SWCNT-coated detector is expected to severely restrict the use of SWCNTs as black coatings for thermal detectors. However, the deposition of SWCNT coatings on a pyroelectric crystal followed by the study of the prominence of the spectral features in the relative spectral responsivity of the resultant pyroelectric detectors is shown to provide an effective method for quantifying the impurity content in SWCNT samples. OCIS codes: 040.3060, 160.4236.

The performance of a pyroelectric detector with a carbon multiwalled nanotube coating was evaluated in the 0.9-14 [micro]m wavelength range. The relative spectral responsivity of this detector was shown to be flat over most of the wavelength range examined, and the spectral flatness was shown to be comparable to the best infrared black coatings currently available. This finding is promising because black coatings with spectrally flat absorbance profiles are usually associated with the highest absorbance values. The performance of the detector (in terms of noise equivalent power and specific detectivity) was limited by the very thick (250 [micro]m thick) LiNb[O.sub.3] pyroelectric crystal onto which the coating was deposited. The responsivity of this detector was shown to be linear in the 0.06-2.8 mW radiant power range, and its spatial uniformity was comparable to that of other pyroelectric detectors that use different types of black coating. The carbon nanotube coatings were reported to be much more durable than other infrared black coatings, such as metal blacks, that are commonly used to coat thermal detectors in the infrared. This, in combination with their excellent spectral flatness, suggests that carbon nanotube coatings appear extremely promising for thermal detection applications in the infrared. OCIS codes: 040.3060, 160.1890.

GaAs micro-electromechanical RF relays fabricated by surface micromachining techniques were characterized for their response to total ionizing dose. Microrelays with two different geometries were studied. For one geometry, changes in switch actuation voltage at moderate dose levels were observed. For an alternative geometry, no change in actuation voltage was observed. A mechanism for dielectric charge trapping and its effect on the electrostatic force is proposed. Micro-electromechanical devices, radiation effects, RF switch.

Research has been conducted on the high-risk persons tested for HIV. The factors critical for HIV prevention program planning which include the reasons for testing and not testing, denial of HIV risk factors and the attitudes toward HIV testing are discussed.

Results are presented from a study of human immunodeficiency virus (HIV) infection rates and the risk factors for HIV infection among female prisoners in New York State. Of interest too were associations between HIV infection and syphilis, hepatitis B, and tuberculosis. The New York State correctional system, the third largest in the US, houses 44,637 inmates in 56 facilities. Roughly 1,800 are female, of whom 77 percent are admitted from New York City (69 percent) or from the counties nearest New York City (8 percent). Blacks, Hispanics, and whites make up 47 percent, 34 percent, and 16 percent of the female inmate population, respectively. Women who entered the system between September and December 1988 were included in the study. Information was collected concerning prisoners' demographic characteristics, fertility, history of drug abuse, and HIV risk factors; in addition, prisoners were tested for syphilis and other diseases. Blood samples were analyzed in a way that did not allow linkage of a result to a particular prisoner. Ninety of the 480 women studied (18.8 percent) tested positive for HIV infection; of these, 53 were Hispanic, 31 black, and 6 white. The majority (40 percent) were between 20 and 39 years of age, and 82 (24 percent) were from New York City. The highest seropositivity rates were found in women aged 30 to 39 (25 percent). Approximately 68 percent reported histories of intravenous drug use, and 7 percent had had sexual contact with a person at risk for HIV infection. Seroprevalence (the rate of positive test results) was higher among less educated women, and almost one third of those born in Caribbean countries tested positive. There was a correlation between positive results from the syphilis test and positive results from HIV testing. The seroprevalence in the current study and in another one concerning male prisoners (17.4 percent) indicates that the prison problem is more severe than was thought. Additional medical care is needed in New York State for its many affected prisoners. (Consumer Summary produced by Reliance Medical Information, Inc.)

This poster is designed to enable viewers to become acquainted with a collaborative process that led to the development of a device that allows homebound elders to safely access delivered food packages. The Open-iT addresses a critical need because 7.3% of individuals over age 65 and 12.5% over 75 require assistance with meal preparation. Despite the fact that more homebound elders are receiving home delivered meals each year, inability to safely and adequately access nutritional food, defined as food insecurity, increases with functional impairments. Viewers of this poster will learn how occupational therapy fieldwork, accompanying a course in aging, led to identifying problems that most New Yorkers have in opening packages they receive from Citymeals-on-Wheels. Systematic problem-solving by students resulted in 1) surveying elders in the community about their ability to access food, 2) designing a device and piloting it with elders, and 3) developing a prototype of the multi-purpose device. Three classes of students, collaboration with faculty, a community agency, and a home delivered meal program, brought this project to fruition.