Sustainable energy at the 100 W level for scientific sites on the Antarctic Plateau: lessons learned from the Polar Experiment Network for Geospace Upper atmosphere Investigations-Automatic Geophysical Observatory project.

The need to provide power to unmanned instrumentation over the course of an entire year on the Antarctic plateau presents a large number of engineering and logistical challenges. Designs formulated in ideal laboratory environments often fail in the Antarctic due to the harsh operating conditions, and field experience is necessary to achieve year-round operation in the 100 W power range. In this paper we present our current power design for the Automatic Geophysical Observatories; a design based on over two decades of experience on the ice and allows for relatively continuous operation at the aforementioned power level.

Ethnic differences in women with HIV infection in Britain and Ireland. The study group for the mrc collaborative study of HIV infection in women.

Objective: To examine ethnic differences in the socio-epidemiological and clinical characteristics of a cohort of women with HIV infection in Britain and Ireland.

Design And Methods: Analysis of baseline data (ethnic group, sexual history, likely route of HIV infection, reasons for HIV testing and first AIDS-defining disease) from 400 women with HIV infection recruited into a cohort study from 15 genitourinary medicine/HIV clinics in Britain and Ireland.

Results: Sixty-five per cent of women were white and 29% black African.

History of NIST's contributions to development of standard reference materials and reference and definitive methods for clinical chemistry.

The issuance of cholesterol as a Standard Reference Material (SRM) in 1967 started the National Institute of Standards and Technology (NIST; then named the National Bureau of Standards) on a major effort to help clinical laboratories establish and improve the quality of measurements they make. NIST now issues three kinds of SRMs for that purpose: analyte samples of certified purity as primary standards, serum samples having certified analyte concentrations as accuracy controls, and materials certified for calibrating instruments. In working with clinical laboratory scientists to establish Reference Methods (RMs) for measuring the analytes, NIST developed Definitive Methods (DMs) to use for evaluating RM accuracy and then used the DMs for assigning analyte values to its SRMs.