Reassessment of lead exposure in New Jersey using GIS technology.

In order to prevent children's exposure to lead, a variety of sources must be controlled. The New Jersey Department of Environmental Protection and Energy (NJDEPE) is using its Geographic Information System to identify areas within Newark, East Orange, and Irvington, New Jersey, where there may be greater environmental exposure to lead. Sensitive populations are identified through the U.S. Bureau of the Census information. Blood screening data provided by the New Jersey Department of Health (NJDOH) provide reported patterns of elevated blood lead in the study area. Comparisons of these spatial patterns will assist the NJDEPE in its soil sampling activities and lead exposure research, will provide information for public education, and will provide valuable information on sections of the study area where further screening and public education may be needed.

Potentiation of the toxicity of basic peptides from rattlesnake venoms by sodium acetate.

The potentiating effect of sodium acetate on the toxicity of crotamine from Crotalus durissus terrificus venom, E toxin from Crotalus horridus horridus venom, and myotoxin a from Crotalus viridus viridis venom was examined. Subcutaneous injection of 6.3 mg/kg body weight of either crotamine or E toxin in 0.6 ml of water or myotoxin a in 0.6 ml of 0.05 M Tris/0.1 M NaCl buffer, pH 9.0, failed to produce lethality in mice. Injection of either E toxin or crotamine at doses of 4.0 mg/kg in 0.6 ml of 20 mM phosphate, pH 7.2, containing 1 M sodium chloride also failed to produce lethality. However, when any of the toxins were injected in 0.4 ml of 1 M sodium acetate, pH 7.0, lethality was observed. LD50 values of 1.43 mg/kg for E toxin, 1.39 mg/kg for crotamine and 0.56 mg/kg for myotoxin a were determined under these conditions. Lethality was also observed when either sodium propionate or sodium butyrate was used as a carrier for E toxin. The effect of these two buffers on crotamine and myotoxin a was not examined. Injection of E toxin s.c. in water followed at various time intervals with i.p. injections of 1 M sodium acetate produced lethality, even when the acetate was injected up to 4 hr after the toxin challenge.

Statistical power in physical anthropology: a technical report.

A statistical power analysis of The American Journal of Physical Anthropology (Volume 44, 1976) was conducted. Twenty-five articles, which included 3,304 major significance tests, constituted the final sample. Resultant power estimates of 0.38, 0.62, and 0.81, corresponding to small, medium, and large population effects respectively, were obtained. Although the medium effect size estimate falls short of the recommended 0.80 level, the statistical power of physical anthropological research fares well relative to several of the social scientific fields of inquiry.

Influence of reading level difficulty on the disfluencies of normal children.

This study assessed the effect of increasing the difficulty of reading material on the frequency and type of disfluency in the oral reading of normally fluent elementary school children. Eighty children participated in the study. Ten boys and 10 girls each, from Grades 3, 4, 5, and 6, read five 200-word passages, corresponding to one grade below their school placement, the grade of their school placement, and one, two, and three grades above their school placement. Results indicated a significant increase in total moments of disfluency and four specific types of disfluency as the difficulty of reading material increased. The data revealed a tendency for "stuttering" disfluencies to increase more in frequency than "normal" nonfluencies. Results are discussed with respect to theoretical and experimental implications.

Toxicity of aquatic herbicides to Daphnia magna.

Accurate determination of the acute toxicities of a series of 16 aquatic herbicides to Daphnia magna reveals that several of them may present a hazard to food-chain microfauna whether the compounds are environmentally destroyed or not.