Building a Bicycle-Powered Centrifuge

Centrifuges are very common instruments utilized in research and clinical settings. The purpose of a centrifuge is to separate the components of a mixture using centrifugal force. An example of a process that utilizes centrifugation is the acquisition of a hematocrit, where red blood cells are separated from blood plasma and the other cellular components. Industrial centrifuges are expensive and generally employed in academic or clinical contexts. A bicycle centrifuge, on the contrary, may be designed and implemented in more generalized settings. Moreover, a bicycle centrifuge affords the opportunity to relate principles in physics to concepts specific to other scientific disciplines, such as biology and kinesiology

Consensual sex between men and sexual violence in Australian prisons

Estimates of the incidence of sexual coercion in men’s prisons are notoriously variable and fraught with conceptual and methodological problems. In 2006–2007, we conducted a computer-assisted telephone survey of a random sample of 2,018 male prisoners in New South Wales and Queensland. Of 2,626 eligible and available inmates, 76.8% consented and provided full responses. We asked about time in prison, sexual experience, attraction and (homo/bi/heterosexual) identity, attitudes, sexual contact with other inmates, reasons for having sex and practices engaged in, and about sexual coercion, including location and number of perpetrators. Most men (95.1%) identified as heterosexual. Of the total sample, 13.5% reported sexual contact with males in their lifetime: 7.8% only outside prison, 2.8% both inside and outside, and 2.7% only inside prison. Later in the interview, 144 men (7.1% of total sample) reported sexual contact with inmates in prison; the majority had few partners and no anal intercourse. Most did so for pleasure, but some for protection, i.e., to avoid assault by someone else. Before incarceration, 32.9% feared sexual assault in prison; 6.9% had been sexually threatened in prison and 2.6% had been sexually coerced (‘‘forced or frightened into doing something sexually that [they] did not want’’). Some of those coerced reported no same-sex contact. The majority of prisoners were intolerant of male-to-male sexual activity. The study achieved a high response rate and asked detailed questions to elicit reports of coercion and sex separately. Both consensual sex and sexual assault are less common than is generally believed