ABSTRACT
We study InAs nanowire resonators fabricated on sapphire substrate with a local gate configuration. The key advantage of using an insulating sapphire substrate is that it results in a reduced parasitic capacitance, thus allowing both wide bandwidth actuation and detection using a network analyzer as well as signal detection at room temperature. Both in-plane and out-of-plane vibrational modes of the nanowire can be driven and the nonlinear response of the resonators studied. In addition, this technique enables the study of variation of thermal strains due to heating in nanostructures.
ABSTRACT
The first estimates of the seroincidence of human immunodeficiency virus type 1 (HIV-1) and of the risk factors for seroconversion in a cohort of high-risk patients attending sexually transmitted disease (STD) clinics in India are reported. Between 1993 and 1995, 851 HIV-1-seronegative persons were evaluated prospectively every 3 months for HIV infection and biologic and behavioral characteristics. The overall incidence of HIV-1 was 10.2/100 person-years (95% confidence interval, 7.9-13.1). The incidence among commercial sex workers (CSWs) was 26.1/100 person-years, compared with 8.4 among non-CSWs. Recurrent genital ulcer disease and urethritis or cervicitis during the follow-up period were independently associated with a 7- (P < .001) and 3-fold (P = .06) increased risk of HIV-1 seroconversion, respectively. Because of the association of recurrent ulcerative and nonulcerative STDs with HIV-1 seroconversion in this setting, behavioral and biologic measures directed at the prevention and control of STDs would be expected to greatly reduce the transmission of HIV-1 infection in similar high-risk groups.
