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Many people grew up on the principle that a good workout consists of three basic components: warm-up, conditioning bout/activity, and cool-down. For those who participated in competitive athletics, the warm-up period seemed just as long as the activity or workout itself; but it was and remains the most important part of any workout. This article describes the three parts of a complete workout, along with a discussion on the current research that has explored a different variation of the workout once taught.

Both selenite and tellurite caused lysis of normal sheep erythrocytes in vitro. GSH-deficient sheep erythrocytes were considerably more resistant to haemolysis than normal cells. This effect was independent of the biochemical lesion responsible for GSH-deficiency (amino acid transport lesion or γ-glutamyl cysteine synthetase deficiency). These and other observations directly implicate intracellular GSH in the lytic mechanism. Selenite and tellurite-induced haemolysis therefore provides a simple method for detecting GSH-deficient cells. The lytic effect of selenite may explain some of the symptoms associated with selenium poisoning.

One method for identifying contingency relationships in a sequence of observed behaviors studies occurrences of matching behaviors at successive event or time steps from a criterion event. This paper briefly summarizes the method and presents a computer program for generating lag conditional probabilities and associated measures for assessing statistical significance.

It is not necessary to define structured programming in detail, but allow me to characterize it in terms that will be useful later. Structured programming is a way to reduce the complexity of the programming process by several means. First, it limits the allowed control structures to sequencing, looping, and alternation. These structures all have the property of one input and one output. Closely related to this is the idea of block structure, or localization of actions that are only relevant to a particular part of the computation. Similarly connected is the idea of closed subroutines and modules which do specific functions and can be understood independently of the context of the program in which they appear.

Procedure timing is important in program performance improvement. The feasibility of such timings is discussed in relation to commonly used computers and operating systems. Some simple design criteria are described which facilitate such timing in an operating system. Finally, some observations are made on how clocks might be made available at the hardware level to further facilitate procedure timing.

Three stages of the development of programming languages are examined and compared with similar stages in the development of operating systems. It is noted that not only do these stages agree but particular developments within these stages also have remarkable similarities; some of these are superficial while others are deeper. The parallels are used to note that certain developments have yet to occur in operating systems. Finally, the essential identity of purpose of programming languages and operating systems is discussed.

A new, rapid and specific method for the determination of reduced glutathione has been developed. The method differs from enzymic methods described previously in that reduced glutathione is a substrate for the enzyme used in the assay. The assay is based upon the reaction C6H3(NO2)2Cl + GSH / C6H3(NO2)2SG + H+ + Cl−, catalysed by glutathione S-transferases (e.g., EC 2.5.1.13) from rat liver. Other thiols found in tissues do not interfere in the assay. Results obtained by applying the present method to various tissues were consistently lower than those from the DTNB method.

A project to produce a kernel-based, message-passing version of UNIX is described. The system is designed to be (1) useful in teaching operating systems, (2) easily changeable, (3) easily portable, and (4) a vehicle for studying the message-passing approach to operating systems design. The system calls normally handled by the UNIX kernel are handled by system processes, each of which operates in its own address space. Interprocess communication and process environment management is done by a small kernel. The design and implementation of the system are described. Message passing as a system design method is evaluated in this context and compared with the procedure call orientation of standard UNIX. The message-based design proved successful in creating a modular and understandable system.