The state of stress in the crust is an important factor in the design and performance of underground excavations, the behaviour of oil reservoirs and in the design and construction of major civil works such as dams, bridges and road cuttings. A compilation of 'near surface' stresses, measured from tunnels, mines and rock outcrops has recently been conducted by Brown and Windsor (1990). This compilation has been extended to include the results from more than 40 earthquake focal mechanisms, and breakout data from 31 deep (>1 km) drill holes.

Amino acid analysis has been performed on the products of four simultaneous separate thermal copolymerizations of a set of 18 amino acids. Four analyses have been performed also on aliquots of one of the products. Standard deviations have been calculated for the analyses of the products of the four separate copolymerizations, and for the four aliquots of one copolymerization. All calculations indicate a high reproducibility in the copolymerization reactions.

A number of copoly(alpha-amino acids) have been prepared thermally; some have been found to function as inhibitors of glyoxalase I, an enzyme which occupies a central position in Szent-Györgyi's theory of tumour genesis. These polymers are also of interest in the search for synthetic peptides having carcinostatic activity, since many natural peptides are active. The way in which the inhibitory activity varies with composition of the synthetic polymers has been investigated. Various properties (hydrophobicity, molecular weight, u.v. absorption, kinetic type) have been examined in a search for correlates of inhibitory activity. The relationship to the origin of enzyme control mechanisms is discussed.

AbstractErhitzt man Ammoniak (I) und Formaldehyd (II) im Molverhältnis 1:3 unter Stickstoff 8 Stunden auf 185°C, so entstehen neben Urotropin und Polymeren in einer Gesamtausbeute von 0,002 bis 0,007% die dünnschichtchromatographisch und mit einem automatischen Aminosäuren‐Analysator identifizierten Aminosäuren (III)‐(IX).

Hydrolyzates of aqueous extracts of Apollo 11 fines, an Apollo 12 trench sample, and an Apollo 12 surface sample have been analyzed on an ultrasensitive amino acid analyzer. The total content of amino acids recovered ranged from 20 to 70 parts per billion of lunar soil. Amino acids are not recovered by the direct hydrolysis of lunar fines, presumably because of decomposition in the presence of the large excess of lunar mineral. As judged by retention time, glycine is the dominant amino acid found; alanine is secondarily present in each case in the profile. Only a few amino acids have been recorded in each analysis. The pattern is relatively consistent in the samples from the three locations; the pattern from either hydrolyzed or unhydrolyzed extracts differs markedly from that of hydrolyzed or unhydrolyzed handprints. The evidence is not consistent with contamination of the kind expected by many investigators.

The eighteen amino acids common to protein have been simultaneously condensed through the N-carboxy anhydrides. Nine of these monomers had first to be specially protected by groups which could subsequently be removed in a single operation. The polymer obtained resembles in quantitative composition an average natural protein. The nutritional and other significances of this type of polymer are discussed.

Experiments imitating spontaneous geothermal occurrences have yielded most of the amino acids found in protein. All of the amino acids found in protein are simultaneously condensed, by heating in a range of appropriate conditions, to polymers which have many of the properties of proteins. These properties include molecular weights of many thousand, digestibility by proteolytic enzymes, and catalytic activities. One of the other properties is the tendency to form structured units; these units have many of the attributes of biocells. The processes indicated, and others, comprise a conceptual continuum which, according to accumulated information, must have occurred under the conditions existing in regions of the primitive Earth.

Proteinoids prepared by thermal copolymerization of 18 common amino acids have been analyzed. Conditions for quantitative recovery of the total amino acids following hydrolysis have been established. The effects of various amino acid reaction mixtures upon the composition of the polymers obtained have been studied.