Leucocyte values of alpha-L-iduronidase activity in mucopolysaccharidosis I

Participants in many sports, such as wrestling, gymnastics, and light-weight crew, attempt to reduce body weight to achieve a maximum ratio of muscle strength to body weight. Such weight reduction should result only from reduction in excess body fat. In most instances, weight reduction should be achieved at a rate of no more than 1 kg a week, through a modest reduction in diet and a moderate increase in exercise. More rapid weight reduction by starvation and dehydration compromises strength and endurance. Athletes attempting to gain weight should increase weight as muscle mass, not fat. Muscle mass is increased only through muscle work supported by an appropriate increase in food intake. No food, vitamin, drug, or hormone will increase muscle mass. It is recommended that the high caloric diet required to support muscle growth from increased work should be low in animal fats and cholesterol.     

Strain gauge readings on a programmable pocket calculator

Programs and command instructions are described for three readily available and established programmable pocket calculators which are an aid to the reduction of readings for rosette strain gauges both into principal strains and stresses, and also to the corresponding maximum shear stresses.     

Genital sex pheromones of ixodid ticks: 1. Evidence of occurrence in anterior reproductive tract of American dog tick,Dermacentor variabilis (Say) (Acari: Ixodidae)

The occurrence of a genital sex pheromone in the anterior reproductive tract of partially fed femaleDermacentor variabilis was demonstrated by extraction and bioassay. A new type of bioassay, the neutered female assay, was developed to test the potency of extracts or chemically defined fractions to stimulate males to copulate. Electrophysiological tests confirmed the ability of males to detect the pheromone with sensilla on their cheliceral digits. Males of bothD. variabilis andD. andersoni exhibited neuronal excitation when stimulated with extracts of theD. variabilis reproductive tissues. The pheromone, which is soluble in methanol, was fractionated and found to contain at least two fractions that stimulated copulation by sexually excited males. Evidently, the pheromone is a mixture of two or more compounds. Histologic, ultrastructural, and histochemical studies suggest the vestibular vagina as the site of genital sex pheromone occurrence, presumably from secretions of the surrounding lobular accessory gland. The identity of the compounds that comprise the pheromone remains unknown.Supported by grants AI10986 and AI10987 from the National Institute of Allergy and Infectious Diseases, National Institute of Health, U.S. Public Health Service, Bethesda, Maryland 20205.     

An electron microprobe study of a mature cement paste

A portland cement paste 23 years old, and essentially fully hydrated, was studied by electron probe microanalysis. X-ray images indicated that the shapes of the original, largely polymineralic cement grains, and those of the regions occupied by the individual phases within them, are substantially preserved in the hydrated material. This was shown especially clearly by the Mg and Fe images, probably because these elements do not readily migrate in the alkaline medium. Estimation of individual phase compositions is rendered uncertain because of possible admixture of phases on or below a micrometer scale, but the atomic ratios relative to Ca are, approximately: Mg 0.03, Al 0.08, Si 0.60, S 0.03 and Fe 0.015 (Ca:Si 1.67) for the C-S-H, and Al 0.40, Si 0.33 and Fe 0.27 for the hydrogarnet.     

Cerebrospinal fluid findings in asymptomatic patients with reactive serum fluorescent treponemal antibody absorption tests

It is common to examine the cerebrospinal fluid in untreated or inadequately treated asymptomatic patients with a reactive serum fluorescent treponemal antibody absorption (FTA-ABS) test before initiating antibiotic therapy for syphilis. This prospective study evaluated the usefulness of such examination. Four hundred thirty-two patients over 40 years old, reporting for annual physical examination, had a serum FTA-ABS test. Thirty-seven (8.6%) patients and 2 of 4 spouses were reactive repeatedly. Of the 39 patients with reactive tests, 7 had a history of penicillin therapy for syphilis, 5 had received heavy metal therapy, and 27 had no history of syphilis. These 39 patients had a neurological examination, serum VDRL, Treponema pallidum immobilization (TPI), and repeat FTA-ABS tests by two other laboratories. The TPI test was reactive in 30 (77%). Four had nonspecific neurological signs. Routine CSF examination (cells, total protein, VDRL, glucose, IgG%) on 30 patients with a history of inadequate treatment had a low diagnostic yield. Two patients had an unexplained total protein elevation (57 and 61 mg/dl) and 1 had a mildly increased IgG% (15%). All cell counts, VDRL tests, and glucose levels were normal. Agarose electrophoresis demonstrated one or more CSF immunoglobulin bands in 10 (36%) of 28 patients, possibly representing an immunological marker of past or latent central nervous system infection.     

Properties of metal-dielectric codeposited films

Optical, electrical, mechanical and corrosion properties have been investigated in the following codeposited metal-dielectric systems: CrSiO₂, CuSiO₂ and (Cu, Zn)SiO₂. The studies were performed in a compositional range of 9–95% Cr, 17–87% Au, 87–99% Cu and 65–85% brass. The films were codeposited in an NRC triode sputtering unit where a variable target aperture was used to control the composition during a single pumpdown. The composite film thicknesses ranged from 200 to 1500 Å. The scratch and corrosion resistance and hardness of the composite films showed considerable improvement over the metal component alone. Marked changes were observed in the reflectance and transmittance spectra with relatively small compositional changes. The data on the optical properties including solar reflectance factors DW (nm) and P%, sheet resistance, scratch and corrosion resistance are presented as a function of composition and thickness of the codeposited films.