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Problems which the solid propellant rocket engineer will encounter in designing for long-term storage in a radiation environment are discussed. A summary of present knowledge of the radiation environment is given. Mechanisms of radiation degradation and its effects on tensile properties of propellant binders are discussed qualitatively. Data from a program of irradiation of several propellants is presented. Properties of two of the propellants were changed significantly by doses of the order of 4 x 10(exp 6) rads.

The relationships between observable changes in sociocultural behavior on the one hand and underlying value systems on the other is examined in two communities that stem from a single sociocultural tradition but that recently diverged because of differential exposure to economic development. Value preferences of individuals in each community were elicited by structured questionnaires, which allowed operational measurement of values and statistical testing of differences within and between the community samples. The findings are explained with reference to the nature of the behavioral responses of individuals to perceived modifications (related to economic development) in their environments.

1. 1. Thirty-five cases and forty operative procedures for biliary strictures are reviewed and evaluated over a ten-year period. 2. 2. Statistics on nine cases of stricture treated with a Vitallium tube prosthesis are presented. 3. 3. Experimental and clinical evidence is presented in support of the time interval a prosthesis used in biliary intestinal anastomosis should be left in place. 4. 4. Clinical support is presented for the use of the Vitallium tube in difficult reconstructive problems. The possibility of secondary operations when these tubes are used is discussed, but the simplicity of the secondary procedure is such that the use of a semi-permanent prosthesis is not contraindicated.

SummaryRepeated intravenous injections of homologous erythrocytes, begun in the early neonatal period, later resulted in the inability of the recipients to destroy rapidly the same homologous erythrocytes. This behavior contrasted with that of control chickens from the same hatching, which uniformly and rapidly destroyed the same donor blood.

An analysis of 15,000 repair estimates written nationwide on 1973 model passenger cars has been completed by State Farm Mutual Auto Insurance Company. Among the findings presented in this paper are the distribution of impact points around the car, distribution of repair cost, repair and replacement frequencies of certain components, and an analysis of repair cost spending by component assembly. A procedure is described which will monitor the crash damage sustained by new cars through the systematic collection and analysis of insurance company damage repair estimates. The availability and limitations of other insurance industry data sources are also discussed.

The experience with fifty-three cases of complete heart block at the University of California Medical Center in a ten-year period was reviewed. Of twenty-two nonsurgical cases, the average survival time from onset of disease under medical management without benefit of the artificial pacemaker was nineteen months, in contrast to one death in fourteen patients in whom internal pacemakers were implanted. The advent of the subcutaneous pacemaker and the coil electrode has made this method of treatment more satisfactory. Methods of implantation, complications and results of steroid therapy were reviewed. It was found that syncope is a grave prognostic sign in these patients. On the basis of this study, it is recommended that the use of implantable pacemakers should be considered in patients with intractable heart block, whether caused by surgical trauma or acquired heart disease.

In a previous study, the survival time of transfused erythrocytes was determined in dogs before and after total body perfusion with a pump oxygenator. 1 In that study, pooled homologous blood taken from the oxygenator and tagged with chromium survived longer in the perfused, thoracotomized dogs than in the control dogs not operated on. Survival time of the homotransfused tagged red blood cells in the perfused animals, however, was still shorter than the survival time in dogs transfused with their own blood. Further experiments in which a dog's own blood was run through the oxygenator without the addition of homologous blood showed that trauma to the erythrocytes in itself specifically accounted for a decrease of approximately 6 days in survival time. There are 2 possible explanations for the relative prolongation of survival time in the perfused dogs. One is that the perfused animal contributed approximately 25% of his own red

Closed chest cardiac resuscitation has proved to be a most effective technic for emergency resuscitation or circulation in the event of sudden circulatory arrest. It is the method of choice in the treatment of this catastrophe. Technical recommendations suggest a rate of thirty to forty strokes a minute as a nontraumatic technic of external cardiac compression. Utilizing this technic, survival has been effected following circulatory arrest in fifteen patients; five of these patients required ventricular defibrillation.