Laboratory analogue of a supersonic accretion column in a binary star system.

Astrophysical flows exhibit rich behaviour resulting from the interplay of different forms of energy-gravitational, thermal, magnetic and radiative. For magnetic cataclysmic variable stars, material from a late, main sequence star is pulled onto a highly magnetized (B>10 MG) white dwarf. The magnetic field is sufficiently large to direct the flow as an accretion column onto the poles of the white dwarf, a star subclass known as AM Herculis. A stationary radiative shock is expected to form 100-1,000 km above the surface of the white dwarf, far too small to be resolved with current telescopes. Here we report the results of a laboratory experiment showing the evolution of a reverse shock when both ionization and radiative losses are important. We find that the stand-off position of the shock agrees with radiation hydrodynamic simulations and is consistent, when scaled to AM Herculis star systems, with theoretical predictions.

Pregnancy and its outcome among hospital personnel according to occupation and working conditions.

Relationships between occupation, working conditions, and the development and outcome of pregnancy were analysed on a sample of women employed in hospital during their pregnancy. Ancillary staff members experienced more uterine contractions during pregnancy, more preterm deliveries, and more low birthweight infants than those performing other duties; this remained true after adjusting for social characteristics. The rate of preterm delivery was significantly higher in the presence of at least two of the following arduous working conditions: stand-up work, carrying heavy loads (exclusive of patients), and heavy cleaning tasks; this was so, whatever the occupation.

[Indigenous, introduced and airport malaria in Europe.]. / Paludisme autochtone et introduit en Europe.

Mainly due to P. vivax, the autochtonous malaria - sometimes caused by P. malaria, scarcely by P. falciparum - is spread in the whole Europe until the 18th century, decreasingly during the second part of the 19th century, while the latest documented cases were noticed in Macedonia, 1974. In France malaria spontaneously disappeared in 1943 on the mainland, and after, DDT house-spraying, in Corsica, 1959-60 (in spite of a temporarily reintroduction run in 1970). Malaria is now eradicated from Europe officially since 1975. Since 1969, approximatively 60 cases of autochtonous "airborne or airport malaria" have been officially reported from various European countries : Belgium, Germany, Italy, Netherlands, United Kingdom, Spain, Swiss, and France. Most of the 23 cases run into France were due to P. falciparum and appeared during summer. All patients were living, working or both, in the vicinity of an international airport or harbour (2 cases). Few of theses cases queerly involved a second-step carriage of Anopheles. The illness is usually severe and case fatality rate is therefore high, because of the subject's absence of premunition and no history of tropical travel, and then, the infection may be unfortunately misdiagnosed. According to the International Health Regulations, disinsection of aircrafts must be systematically done and even enhanced as soon as possible. On the other hand some of new methods for the aircraft disinsection and improved international vector control must be developped.

Determination of the blood lactate:pyruvate ratio as a noninvasive test for the diagnosis of zidovudine myopathy.

OBJECTIVE: To evaluate the use of the lactate: pyruvate ratio as a test for the detection of zidovudine myopathy. METHODS: Twenty consecutive human immunodeficiency virus-infected patients with muscle involvement and 20 without muscle involvement were studied prospectively. Blood lactate and pyruvate levels and serum creatine kinase levels were tested, muscle involvement was assessed both clinically and electrophysiologically, and muscle biopsy was performed in patients with myopathy. RESULTS: Nine patients had biopsy-proven zidovudine myopathy. All 9 had a high lactate:pyruvate ratio, with elevations on 2 of 2 determinations in 6 patients and on 1 of 2 in 3 patients. Two of 11 patients with other myopathies and 2 of 20 patients without myopathy had a high lactate:pyruvate ratio on 1 of 2 determinations. CONCLUSION: The lactate:pyruvate ratio, when determined repeatedly, is a sensitive test for detecting mitochondrial muscular toxicity of zidovudine.