Spectral indices of cardiovascular adaptations to short-term simulated microgravity exposure

We investigated the effects of exposure to microgravity on the baseline autonomic balance in cardiovascular regulation using spectral analysis of cardiovascular variables measured during supine rest. Heart rate, arterial pressure, radial flow, thoracic fluid impedance and central venous pressure were recorded from nine volunteers before and after simulated microgravity, produced by 20 hours of 6° head down bedrest plus furosemide. Spectral powers increased after simulated microgravity in the low frequency region (centered at about 0.03 Hz) in arterial pressure, heart rate and radial flow, and decreased in the respiratory frequency region (centered at about 0.25 Hz) in heart rate. Reduced heart rate power in the respiratory frequency region indicates reduced parasympathetic influence on the heart. A concurrent increase in the low frequency power in arterial pressure, heart rate, and radial flow indicates increased sympathetic influence. These results suggest that the baseline autonomic balance in cardiovascular regulation is shifted towards increased sympathetic and decreased parasympathetic influence after exposure to short-term simulated microgravity.     

Another look at physicians' treatment of men and women with common complaints

A recent study of San Diego patients found that men received more extensive and appropriate diagnostic workups than women did for five common complaints (Armitage, K. J., Schneiderman, L. J., & Bass, R. A. Journal of the American Medical Association 1979, 241 2186–2187). This article is a broader analysis of medical care given to men and women for those complaints (fatigue, headache, vertigo/dizziness, chest pain, back pain), and it uses a national survey of ambulatory-care visits. We find that medical care is usually similar for men and women. When significant sex differences do appear, they often show that women receive more medical care during a visit. To some extent, differential care stems from different medical needs that men and women with a complaint have; when some medically relevant factors are controlled, half of the significant sex differences disappear. But half persist, and this suggests that psychosocial factors also underlie differential care for men and women. These may originate with patients (for example, their requests for particular services) or with physicians (for example stereotypes of men and women patients). In contrast to the San Diego study, the national data show that (1) women sometimes receive more diagnostic workups for the five complaints, and (2) when medical factors are controlled, sex differences in the extent and content of workups disappear. The only exception is that men with vertigo/dizziness receive more appropriate workups.     

Delinquency: the learning disabled students reaction to academic school failure?

Support for the relationship between academic performance and delinquency is offered. Additionally a review is provided describing the learning disabled male adolescent as the target population for experimental research.