Noninvasive predictors of sudden cardiac death in men with coronary heart disease. Predictive value of maximal stress testing

In a follow-up study of 1,852 men with coronary heart disease, 195 deaths occurred within the first 3 years (33 +/- 13 months [mean +/- standard deviation]). Analysis of these cases indicated that the risk of sudden cardiac death in ambulatory men with clinical manifestations of coronary heart disease may be readily estimated from noninvasive clinical and exercise criteria. The important predictors are indexes of the severity of coronary heart disease and impairment of peak left ventricular function demonstrated with symptom-limited maximal exercise. The advantages of these predictors are that they may be elicited on the initial study as well as on follow-up noninvasive examinations of ambulatory patients. The appearance of nonelectrocardiographic predictors in serial examinations may provide an indication for invasive studies and be a more important finding than the ischemic S-T reponse to exertion.     

Nucleation and growth of sputtered and evaporated trigonal selenium films

Critical nucleation temperature experiments, scanning electron microscopy and light microscopy were used to study the nucleation and growth of trigonal Se films deposited by evaporation and sputtering on both gold and anodized aluminum substrates. The major nucleation and growth processes were shown to be the condensation of Se₂ molecules followed by their polymerization into Se_n chains, where n can be very large. In sputtering, these chains have a higher surface mobility, due in part to their higher residual kinetic energy, and thus they can form large trigonal Se crystallites. The high incident kinetic energies also allow the Se to break through the surface contamination of the substrate. This is important since the Se chain mobility should also be dependent on the surface free energy and on the nucleation site density of the substrate. Very adherent large-grained trigonal Se films were grown by sputtering on Au substrates. It was shown that nucleation sites for the large trigonal Se crystallites were not created by the incident flux but are inherent on the substrate. The high energy incident flux did, however, increase nucleation probability for the initial Se₂ condensation. For sputtering on anodized aluminum substrates the combination of low surface energy and high nucleation site density decreased chain mobility and thus prevented formation of large crystallites.     

Studies in approximation methods—I: Splines and control via discrete dynamic programming

A novel approach is suggested for alleviating the curse of dimensionality in discrete dynamic programming as applied to optimal control problems. By using multidimensional B-splines to approximate the overall minimum objective and optimal control function, a significant reduction of computer storage is made. The ease and accuracy of this approach is demonstrated on a two-dimensional control problem. Extensions of this procedure are also proposed that result in increased accuracy.     

Kinetics for unidirectional endwise chain depolymerizations. Experiments with amylose in aqueous alkaline solutions

A kinetic model for the unidirectional endwise chain-propagated depolymerization of a linear polymer is described in terms of three pseudo-first-order rate constants: k₁ for the unzipping itself; k₂ for termination through the formation of stable endgroups; and k₃ for termination through complete degradation of polymer chains. It is shown that the calculated zip length, ν = k₁/(k₂ + k₃), will decrease as the initial substrate D.P. is reduced. For the dimer, a maximum value of ν = 1 is expected. During the anaerobic degradation of potato amylose in aqueous alkaline solutions, k₁ decreases and k₂ increases in value as the initial amylose concentration is raised. As a result, quantitative depolymerization occurs at low substrate concentrations, while at raised starch levels an alkali-stable residue is formed. It is proposed that intermolecular association between polymer chains causes these kinetic differences. For amylose, the constants k₁, k₂, and k₃ are approximately related by the ratio 1000:1:1 or 1000:0:1; and for the homologous disaccharide, the ratio is 10:1:10. The relevance of these findings to the kinetics of cellulose decomposition in aqueous alkali is discussed.     

Castration, circumcision, and anti-Semitism.

In this study, the authors look at whether circumcision is a relevant variable in anti-Semitism as measured in a contemporary male gentile population. The 52-item A-S scale described by Levinson and Sanford was administered to 381 students drawn from various psychology courses at Princeton and Rutgers Universities. The subjects (Ss) included in this study are 142 gentile male undergraduates selected from the larger population and divided into two matched groups of 71 each. No reliable differences in attitude were found between circumcised and uncircumcised subjects. These findings indicate the relative unimportance of circumcision as an isolated factor in anti-Semitism. The implications for the relationships involving circumcision, castration, and anti-Semitism are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in dream recall.

Ss who typically fail to remember dreams at home (nonreporters) and Ss who frequently remember dreams (reporters) slept in the laboratory for 4 nights each. Gradual or abrupt awakenings were made at each EEG Stage-I REM (dream) period. Although nonreporters and reporters did not differ in REM-period frequency or EEG patterns during sleep, nonreporters did report dreaming less frequently following REM-period awakenings. Ss showed self-consistency in frequency of dream reporting and in type of failure to report. Some nonreporters typically failed to remember any content; others typically said they were awake and thinking. Comparisons among reporters and sub-groups of nonreporters for eye-movement frequency, arousal threshold, and dreamlike-report content indicate that it may be useful to distinguish different kinds of nonreporters. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Catalytic dehydrogenation of coal: Part 7. The effect of some catalyst variables

When vitrinite is catalytically dehydrogenated in the presence of phenanthridine as vehicle, the yield of hydrogen is not greatly influenced by the catalyst support or the concentration of metal on the support. The metal used has a large effect, palladium giving the highest yield of hydrogen.     

The Edwards SD scale: A short form of the MMPI?

Edwards has described a rationale for predicting MMPI scores based upon social desirability response bias. The clinical utility of this technique was examined by comparing the predicted average MMPI profile with the average profile actually obtained by college males. The estimated and actual profiles were markedly discrepant, indicating that Edwards' SD scale is not a useful substitute for the MMPI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)