The possibility of attenuation of microseismic waves due to the presence of an upward folding of the ocean bottom into the liquid is discussed in this paper. The upward folding of the ocean bottom has been idealized by means of an irregularity in the form of a rectangle intruding into the liquid and the evaluation of the displacement component at any point of the solid medium has been carried out in two stages. First, the change in the incident mode of the surface wave due to the presence of the rectangular irregularity has been determined, and second, the subsequent change of the resulting displacement components due to the termination of the liquid layer and the step change in elevation of the solid medium at the continental margin has been discovered. Finally, numerical calculation has been made to determine the attenuation of the microseismic waves of different periods due to the presence of the rectangular irregularity at the ocean bottom.

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The effect of composition and controlled thermomechanical process parameters on the mechanical properties of HSLA steels is modelled using the Widrow-Hoff's concept of training a neural net with feed-forward topology by applying Rumelhart's back propagation type algorithm for supervised learning, using a Petri like net structure. The data used are from laboratory experiments as well as from the published literature. The results from the neural network are found to be consistent and in good agreement with the experimented results.

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Horizontal plate anchors are widely used in civil engineering constructions to resist vertical pulling loads. The available theoretical model suggested by Vesic to estimate the breakout resistance of plate anchors is in significant error, particularly for dense sandy soils. A theoretical model assuming a curved surface of failure through the surrounding soil, to evaluate the ultimate breakout resistance of horizontal plate anchors, has been proposed. It successfully brings out the concept of characteristics relative depth beyond which the breakout factor reaches a constant final value. It is capable of predicting breakout factors for wide range of values of angle of shearing resistance of sand.

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An unsupervised learning technique and an associative memory have been used for encoding weights by a special type of Petri network named Petri neural net for modelling the influence of alloying elements on the final property of the high strength low alloy steel. The combined effects of alloying elements for different strengthening mechanisms is predicted when weights and threshold values are chosen on the basis of metallurgical understanding. The technique is found to be effective to create an associative memory of input-output relations in unknown data sets so that the same can be subsequently be used as a predictive tool.

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Primarily from the point of view of improvement of yield strength due to additions of niobium, titanium and boron in HSLA steels, the experimental steels are divided into five classes. The data are then supplied for learning a Self Organising Map (Kohonen network). It is found that the network with six neurons possesses better capacity of prediction with unknown data. Another effort of clustering the steels according to its major strength contributing mechanisms is also made. But the capacity of the network to cluster unknown data is found to be rather poor and has failed to follow from the metallurgical principles. To avoid this limitation, Learning Vector Quantisation method is adopted to impart a certain amount of supervision in the learning process and it is found that the training pattern of the network attains a good convergence thereby leading to a good predictive ability.

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A boron treated copper bearing HSLA steel containing austenite formers like manganese and nickel, somewhat lower in amount than that in HSLA 100 variety of steel is chosen for the study. The role of thermomechanical processing on the microstructure and mechanical properties of the above steel has been investigated. Differential scanning calorimetric study is carried out for understanding the precipitation behaviour of copper in HSLA steel under the influence of boron. The microstructure of the experimental steel is found to consist of laths of martensites and bainite. MA constituents of ribbon like morphology are observed at the lath boundaries. Higher strength properties of the steel are attributed to the presence of finely distributed precipitates of copper and microalloy carbides.

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Simultaneous measurements of the total geomagnetic field intensity by the same type of the proton precession magnetometers at two stations in NW Turkey have been taken cooperatively by a research group since December 1970. Up to the end of July 1971 mainly three probable local magnetic changes were observed. It was seen that after a decrease in the local field at a magnetic station (Erdek) a few earthquakes occured at either nearly N or S of that station, and after an increase in the local field an earthquake took place nearly W of the same station. In this paper the data and some results of the first part of observations are given.

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Nine isoquinoline alkaloids belonging to the protoberberine, proaporphine and bisbenzyl-isoquinoline series were isolated from Caryomene olivascens (Menispermaceae). Four compounds are new : (-)--norlimacine (4), (-)-caryolivine (), (+)-1, -dehydro--norlimacusine () and N-formylstepharine (). The last one is the first N-formyl derivative to be reported in the proaporphine group. Its biogenetic origin is discussed. Structures were established on the basis of 360 MHz (FT) nuclear magnetic resonance measurements and also by chemical correlation in the case of .

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Two new partially saturated tricyclic ring systems, , a, , 8, , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (a and ), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric -methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of a (trans), (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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Cold-adapted enzymes produced by microorganisms living in permanently cold habitats are characterized by a high specific activity at low and moderate temperatures. Typically they display a high thermosensitivity related to a high flexibility of a part or of the whole molecular edifice. Indeed, this flexibility is apparently essential in counteracting the freezing effect of the low temperature environment on the three dimensional structure, thereby securing an appropriate plasticity as required for catalysis. One of the main strategies selected by extracellular enzymes interacting with large size substrates (α-amylase, proteases etc..) consists of increasing the overall flexibility of the molecular structure by weakening of numerous intra-molecular interactions in all domains of the molecule. However, in the case of enzymes which interact with small size substrates such as for example, phosphoglycerate kinase and chitobiase, only one part of the protein, presumably that related directly or indirectly to the catalytic site, appears to be flexible, whereas the other parts are even more rigid than their mesophilic counterparts, as demonstrated by microcalorimetry and quenching of intrinsic fluorescence using acrylamide. In the case of a cold-adapted cellulase, isolated from an Antarctic bacterium, recent investigations have demonstrated that the flexibility, required for a good accommodation of the large size substrate at low temperatures, is mainly provided by an unusually long and flexible linker connecting the catalytic and cellulose binding modules. This has been demonstrated by x-ray crystallography and small angle x-ray scattering coupled to protein engineering experiments leading to a reduction of the length and to an increased rigidity of the linker. Cold-adapted enzymes such as β-galactosidase and xylanase have been found to be very efficient in milk and baking industry respectively.

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Pharmacokinetics and bioavailability of multivitamin preparations including _1, _, _<12> and/or were studied in human male volunteers. The same dosage of 100 mg thiamine tetrahydrofurfuryl disulfide (_1) was included in both preparations. However, one preparation (Alinamin EX^<(R)>) included high amounts of 100 mg pyridoxine hydrochloride (_), 1500 μg hydroxocobalamin (_<12>) and 100 mg d, l-α-tocopherol succinate (). The other (Alinamin A50^<(R)>) included 10 mg riboflavin (_), 10 mg pyridoxine hydrochloride (_), 20 μg cyanocobalamin (_<12>). the results were as follows : 1) _1 : No difference was observed between AUC of both preparations. T_<max> tended faster in Alinamin EX^<(R)>. ) _ : AUC by administration of Alinamin EX^<(R)> was times larger than in Alinamin A50^<(R)>. ) _<12> : AUC by administration of Alinamin EX^<(R)> was 4 times larger than in Alinamin A50^<(R)>. 4) : A significant increase in plasma was observed by administration of Alinamin EX^<(R)>. AUC represents the area under curve obtained from the blood drug concentration of the time course.

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