First Measurement of the Total Neutron Cross Section on Argon between 100 and 800 MeV.

We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is 0.91±0.10(stat)±0.09(syst) b. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages, where the energy averaged cross sections in this range are 0.60 and 0.68 b, respectively.

Insights into the AHA scientific statement concerning cardiovascular preparticipation screening of competitive athletes.

In 1996 the American Heart Association (AHA) published recommendations concerning the cardiovascular component of the preparticipation exam in competitive athletes as part of an AHA medical scientific statement. This article will review the rationale for the development of such a statement and how it has been incorporated into the current state-of-the-art preparticipation exam of athletes.

Survey of NCAA institutions concerning HIV/AIDS policies and universal precautions.

Attention has recently been focused on issues concerning HIV disease and competitive athletics. These issues have included HIV testing of athletes, participation by HIV-infected athletes, and the practice of "Universal Precautions" by members of the athletic health care team. A survey of all NCAA member institutions was conducted to further investigate these areas. Routine testing for the HIV virus is rare in NCAA member athletic departments. Policies of NCAA member institutions athletic departments concerning participation with HIV virus are few but nearly half restrict participation. Only 12 schools reported having HIV-positive athletes or AIDS-diagnosed athletes at their institutions. There is a need for increased awareness, knowledge, and practice of "Universal Precautions" in all athletic training rooms.

NCAA institutionally based drug testing: do our athletes know the rules of this game?

One aspect of the current drug-testing controversy that has gone relatively unexamined concerns the extent to which student-athletes are fully informed of the testing procedures employed by their institution. College athletes (N = 2,282) participating at 11 NCAA-affiliated institutions nationwide were surveyed as to their awareness of their school's drug-testing program. Results indicate athletes have numerous misconceptions regarding the drug testing to which they may be subjected. Over one-third of the athletes attending "testing" institutions were oblivious to the fact their school was engaged in drug-testing, and more than 70% were unable to correctly identify their school's drug-testing protocol. Implications of such ignorance are discussed.

Effects of a 6-month incentive-based exercise program on adherence and work capacity.

The purpose of the study was to evaluate the effect of behavioral management techniques on exercise adherence linked to improvements in work capacity and maximal oxygen consumption (VO2max). One hundred thirty-seven participants in six different worksites on a university campus (five experimental and one comparison site) completed 6 months of a minimally supervised, incentive-based endurance exercise program. All participants in the experimental group contracted to engage in at least four bouts of 30 min of verified aerobic exercise within a prescribed target heart rate range each week for the duration of the program. Forty dollars deposited at the beginning of the program served as a response cost that could be lost as a result of failure to fulfill the weekly contracts. Individuals in the comparison group participated in a similar 6-month program but without the contracts and response cost strategies. Weekly adherence for both groups was strictly defined as verified fulfillment of all four bouts of exercise. Adherence for the experimental group was 97% by this definition, and adherence for the comparison group was 19% (P less than 0.01). VO2max increased 2.6% (P less than 0.01), and treadmill test time increased 16% (P less than 0.01) in the experimental group after the 6-month program, with no significant changes in the comparison group. Recovery heart rates at 2 and 4 min post-exercise were significantly lower at 6 months in the experimental group but not in the comparison group. These data provide evidence that adherence to a 6-month endurance exercise program can be improved significantly through the use of well conceived behavior management strategies.(ABSTRACT TRUNCATED AT 250 WORDS)

An outbreak of histoplasmosis at an Arkansas courthouse with five cases of probable reinfection.

An outbreak of histoplasmosis occurred at a county courthouse in Arkansas in July, 1975. Fifty cases were identified by symptoms and positive complement fixation (CF) tests and 18 others by the clinical findings alone. Only three positive CF tests (greater than or equal to 1:8) were found in a control group of 55 unexposed persons of the same age. The attack rate for 84 courthouse employees was 52%. Histoplasma capsulatum was isolated from the sputum of two cases, and from bird droppings which had been dumped from the roof of the courthouse two weeks before the epidemic's peak. Window air conditioners apparently helped to distribute infectious particles throughout the building. Nine exposed people had pulmonary calcifications and a negative tuberculin test that were taken as presumptive evidence of previous histoplasmosis. Five (55%) of these became ill. Exposed persons without pulmonary calcifications had an attack rate of 85%. The reinfected cases during convalescence had higher serum CF titers but not larger histoplasmin skin test diameters than the rest of the cases. A microdroplet aerosol of cooking oil was used to simulate air flow patterns during the exposure, and the results agreed with the hypothesized means of infection.