Although a complete oxygen meter is an expensive piece of equipment, homemade circuitry can be a suitable substitute if science teachers are aware of the limitations of the apparatus as well as of certain techniques for effective use. (PB)

A laboratory experiment that demonstrates the effects of various dental materials on a representative enzyme from the pulp is outlined. The experiment encourages students to consider the effects that various restorative materials and techniques might have on enzymes in the living pulp. (Author/MLW)

Describes a system that monitors intestinal motility in vivo which is very sensitive, minimally injurious to the tissue, and inexpensive. Used are two balloons, one of which is inserted into the intestinal lumen and the other suspended from a force transducer. (CS)

Discusses the physiology of endogenous pyrogen (EP), the fever-producing factor of cellular origin. Included are: its hormone-like role, its molecular nature, bioassay procedures, cellular production and mechanisms of EP action. (SA)

Describes experiments which demonstrate how different diets affect the growth rate of earthworms. Procedures for feeding baby worms are outlined, the analysis of results are discussed, and various modifications of the exercise are provided. (CS)

Describes three videocassette formats comparing their technical characteristics to determine which is most suited for a given application. Discusses duplication problems and international exchange of tapes, advising about world standards and conversion from one to the other. Gives guidelines to selecting the proper hardware for different video…

Various safety precautions for the science teaching laboratory are discussed, including rules for pupils, hazards of some reagents, and electrical safety. (SA)

The design and use of an instrument simulator is described. Used for student laboratory experiments illustrating the use of mini-computers, it can provide, at very low cost, a repetitive, repeatable output to duplicate the readout of various instruments such as electrochemical experiments, mass spectrometers, pulsed magnetic experiments,…

Describes a laboratory teaching method in which students are given a simulated research problem to solve in groups by planning and laboratory work. (MLH)

Describes an experiment that utilizes advanced techniques for analyzing complicated nmr spectra that are not first-order. (MLH)

Describes various ways to arrange equipment and utilities in chemical laboratories for both research and teaching purposes. (MLH)

Describes an experiment in which chemical interferences in atomic absorption analyses are examined and measured. (MLH)

This article summarizes conditions and changes in language laboratories. Types of laboratories and equipment are listed; laboratory personnel include technicians, librarians and student assistants. Most maintenance was done by institution personnel; student use is outlined. Professional attitudes and equipment statistics are surveyed. (CHK)

Describes a scheme that uses precipitation, gas evolution, complex ion formation, and flame tests to analyze for the following ions: Hg(I), Hg(II), Sb(III), Cr(III), Pb(II), Sr(II), Cu(II), Cd(II), As(III), chloride, nitrate, and sulfate. (MLH)

Describes a quick, inexpensive laboratory demonstration of Charles's Law. The opening of a large, round balloon is placed snugly over the mouth of a narrow-mouthed 750-mL Erlenmeyer flask, which is then heated in a strong flame. At end of the full procedure, students easily arrive at the conclusion that the volume of a gas is proportional to…