Biomedical subjects

J Tice

Publications and source records attributed to J Tice.

4 recordsLinked to original sources

PubMed2000

Double crystals.

The lowest-energy way to enclose and separate two planar regions of prescribed areas is found, where the energy is given by the l1 norm ('Manhattan metric'), in which horizontal and vertical directions use less energy than other directions, as in some crystals. With the assumption that interfaces carry a fraction lambda of the energy of exterior faces, it is proved that there are three possible types of energy-minimizing double crystals. The dependence of these three types of lambda as well as the ratio of the areas of the two regions is discussed, and some paths for further study are suggested.

Journal Article↗

PubMed1992

Effect of serotesting with counselling on condom use and seroconversion among HIV discordant couples in Africa.

OBJECTIVE: To determine whether HIV testing and counselling increased condom use and decreased heterosexual transmission of HIV in discordant couples. DESIGN: Prospective study. SETTING: Kigali, the capital of Rwanda. SUBJECTS: Cohabiting couples with discordant HIV serology results. MAIN OUTCOME MEASURES: Condom use in the couple and HIV seroconversion in the negative partners. RESULTS: 60 HIV discordant couples were identified, of whom 53 were followed for an average of 2.2 years. The proportion of discordant couples using condoms increased from 4% to 57% after one year of follow up. During follow up two of the 23 HIV negative men and six of the 30 HIV negative women seroconverted (seroconversion rates of 4 and 9 per 100 person years). The rate among women was less than half that estimated for similar women in discordant couples whose partners had not been serotested. Condom use was less common among those who seroconverted (100% v 5%, p = 0.01 in men; 67% v 25%, p = 0.14 in women). CONCLUSIONS: Roughly one in seven cohabiting couples in Kigali have discordant HIV serological results. Confidential HIV serotesting with counselling caused a large increase in condom use and was associated with a lower rate of new HIV infections. HIV testing is a promising intervention for preventing the spread of HIV in African cities.

AIDS Serodiagnosis↗

PubMed1991

Human immunodeficiency virus and malaria in a representative sample of childbearing women in Kigali, Rwanda.

In 1986-1987 a consecutive sample of 3702 women presenting to prenatal and pediatric clinics at the only hospital in Kigali, Rwanda, was screened for human immunodeficiency virus (HIV) and malaria infection. The prevalence of HIV antibodies was 29%, and that of malaria parasites was 9%. HIV antibodies were more prevalent in women from the urban center than in those from the outskirts (31% vs. 20%, P less than .001), and malaria parasites showed the opposite prevalence pattern (8% vs. 15%, P less than .001); after stratifying by location, there was no association between HIV and the presence or degree of malaria parasitemia. HIV prevalence was 45% in women who had received a blood transfusion between 1980-1985 (before screening of donated blood began), and 28% among the great majority (94%) who had never been transfused. HIV prevalence was 44% in single mothers. 34% in women in common law unions, and 20% in those in legal marriages. These high rates of infection in the general population of Kigali highlight the need to develop effective programs for preventing further spread of sexually transmitted HIV.

Adult↗

PubMed1991

Knowledge, attitudes, and perceived risk of AIDS among urban Rwandan women: relationship to HIV infection and behavior change.

We examined factors associated with perceived risk of AIDS, behavior change, and HIV infection in a representative sample of 1458 child-bearing urban women in Rwanda, central Africa. Although 68% of women reported only one lifetime partner, and the majority (87%) lived with a husband or steady partner, the prevalence of HIV antibodies was still high (32%). Before receiving their HIV test results, the women completed a questionnaire about AIDS knowledge, attitudes, and practices. Knowledge about HIV transmission was high, with 96-98% of women correctly identifying the three primary routes of infection. However, only 16% of women reported taking any action to avoid AIDS in the previous year, and most (11%) had done so merely by asking their male partners to change their behavior. Only 7% of women had ever tried condoms, and many (68%) thought they could be dangerous to use. Women who perceived themselves at risk of AIDS (57%) were more likely to report changing behavior; they were also more likely to be infected with HIV. Other factors associated with behavior change included having known someone with AIDS, having discussed AIDS with a male partner, and believing that condoms are not dangerous. Future interventions should enhance perception of risk, encourage male sexual partners to reduce risky behavior, and increase familiarity with condoms.

Adolescent↗