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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We compared three groups of pregnant women: placebo with normotensive women, group A which included preeclamptics, and group which comprised preeclamptics who were supplemented their diets with vitamins C and . MDA increased from 6. ± 2. (placebo) to .48 ± 1.2 (A) and .02 ± 1. nmol/gHb (). NO concentrations were enhanced from 19. ± .2 (P) to 23. ± 6. (A) and 24.1 ± 5. μmol/L (). GSH contents were decreased from 10.42 ± 2. (P) to .02 ± 2.92 (A) and 9.39 ± 1.02 μmol/g Hb (), whereas GSSG concentrations increased from .98 ± .28 (P) to 1.24 ± .29 (A) and 1.08 ± .12 μmol/g Hb (). SOD activity decreased 23% in A and 14% in ; GRx decreased 27% in A and 5.5% in ; GPx decreased 12% in A and 9.6% in . Catalase activity, however, increased 27% in A and 29% in as compared to control. Thus, we conclude that the use of vitamins C and should be considered for the control of certain important biochemical indices during the development of preeclampsia; however, further studies are needed to develop methods for the prevention of preeclampsia in women at high risk.

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Purpose: The purpose of this study was to determine if the optical properties of zirconia and glass–ceramic (

.max) were affected by low-temperature degradation (aging).

Methods: Experiment samples were fabricated with seven zirconia brands (n=10): Zenostar, Zirlux, Katana, Bruxzir, DD-BioZX², DD-cubeX², NexxZr; and

.max were used as a control. This resulted in a total of 80 samples in the experiment. The L*, a* and * were measured for each sample, and then the optical properties including translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) were calculated. The samples were aged (20, 40, 60, 80, 100h), and the optical properties were calculated after each interval.

Results: Most zirconia brands had lower L*, higher a*, higher

* with increased aging, which visually corresponds to darker, redder, and more yellow. Aging also increased CR, lowered TP, and lowered OP. .max was also affected by aging but still had the highest TP (23.9±2.), L* (.±.), and lowest CR (.41±.05) compared to any zirconia. The Zenostar had the closest TP (24.1±.), and L* (90.2±.5) values to .max before aging. However, after 100h of aging, the DD-cubeX² was least effected and had the highest TP (.2±.6) and lowest CR (.43±.01) compared with other zirconia samples and highest OP (11.±.2) of all ceramic samples.

Conclusions: The optical properties of zirconia and

.max materials were affected by aging with the effects increasing with time. The magnitude of change was affected by seven brands of dental zirconia.

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Static characteristics of two different structured InAlGaAs/InAlAs superlattice avalanche photodiodes (SLAPDs) cooled by liquid nitrogen were evaluated at a wavelength of 1.5 μm. The dark current of the SLAPD having a thick superlattice layer of .504 μm was 5×10^-13 A. This was successively reduced by four orders of magnitude compared to that of the thin layer SLAPD of .231 μm at a breakdown voltage of around 20 V. The thickened layer was effective in suppressing tunneling dark current. An output current of 1.×10^-12 A at a bias voltage of 15 V was measured for an optical input with a wavelength of 1.5 μm and a signal power of 1×10^-12 W. This showed a sharp distinction from the dark current.

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Background : Usefulness of endoscopic microwave coagulation therapy (-MCT) was examined in 27 patients with hepatocellular carcinoma (HCC).
Material and Methods : HCC was found in patients with type liver cirrhosis (LC), 16 patients with type C LC, and patients with non non C LC. Median tumor size was 23 mm (solitary lesion , multiple 5). Laparoscopic MCT was performed for S_2-6 lesion and thoracoscopic MCT for lesion under general anesthesia. Linear type ultrasonography was used in every case for monitoring lesion ant therapeutic effect.
Results : Complete tumor necrosis was obtained in 24 cases (%) and local recurrence was found in 5 cases after the observation period of maximum 34 months. Pleural abscess, hemorrhage and hepatic infarction were found in cases without serious outcome.
Conclusions : We conclude that -MCT is quite promising therapy for surface type HCC in term of minimally invasive and curative procedure a time. It is important that sufficient marginal coagulation should be obtained.

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Nアルキル,:9,10-ペリレンテトラカルボン酸モノアンヒドリド=モノイミド[a～]と芳香族アミン(アニリン,p-トルイジン,p-アニシジン,,5-キシリジン,-アミノナゾベンゼン,およびo-フェニレンジアミン)を縮合して非対称型,:9,10-ペリレンビス(ジカルボキシミド)誘導体-N-アルキル-N'-アリール-,:9,10-ペリレンビス(ジカルボキシミド)(〔5a～〕,〔6a～〕,〔a～〕,〔a～〕,〔9a～〕,および〔10a～〕)を合成した. これらの各誘導体はすべて赤色系の色相を示し, 顔料試験の結果N-ブチル-N'-アリール-,:9,10-ペリレンビス(ジカルボキシミド)(たとえば〔5〕や〔6〕)がとくにすぐれた耐光性を示した.

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The effects of dimensions and supporting conditions on the compressive strength and deformation of polyvinylchloride pipes under external pressure were discussed. The following four kinds of pipe supporting conditions were used; (A) compression between two steel plates, () compression between a steel plate and a concave wooden block, (C) compression between two concave wooden blocks, and (D) compression between two concave hard rubber supporters. The main results obtained are as follows.
(1) The relation between the compressive strength P and the dimensions of PVC pipe is given by the following formula, similar to the mid load bending for a both end fixed straight beam with a rectangular section;
P=/·D_m·c₁ (a)
where, l, t and D_m are the length, thickness and diameter of pipe, respectively, c₁ the correction coefficient according to pipe supporting conditions, and σ_b the bending stress in kg/mm². The value of correction coefficient c₁ was .∼1.35 for A-method, 1.35 for -method, . for C-method and 2. for D-method, respectively.
(2) The deflection δ under elastic deformation is given by the following formula;
δ=/ ()
where, is Young's modulus in kg/mm² of pipe material, and c₂ the correction coefficient similar to c₁. The value of c₂ was 2. for A-method.
() It seems reasonable, therefore, that the theory of straight beam may be applied to the compressive strength and deflection of plastics-pipe under external pressure by using the correction coefficient c₁ or c₂.

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Ni-base amorphous alloys with the homogeneous dispersion of nanoscale fcc-Ni particles have been produced in the composition range of 5 to 14 at%Si and to 15%. The particle size and interparticle spacing are 10 and 20 nm, respectively. The alloys exhibit tensile fracture strength (σ_f), Young’s modulus () and hardness (H_v) which are higher than those of the corresponding amorphous single phase alloys, accompanying an increase in fracture elongation (ε_f). The highest values of σ_f, , H_v and ε_f in the mixed phase state of Ni–Si– alloys, i.., 3400 MPa, 130 GPa, 960 and 2.%, respectively, are found for . Addition of Cr increased σ_f and ε_f, their highest values being 3900 MPa and .%, respectively for ()

97Cr₃

. The increase in σ_f by the dispersion of the fcc-Ni particles is presumably because the fcc-Ni particles are higher in mechanical strength than the amorphous phase because of the absence of internal defects and can act as a barrier to suppress the shear deformation of the amorphous matrix. The increase in ε_f is due to the suppression of the inhomogeneous shear deformation. The effectiveness of Cr for the increase in σ_f and ε_f is presumably attributed to a further refinement of the fcc-Ni particle size due to the increase in glass-forming ability.

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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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A sample of [

3H

] tobrarnycin (5, 000 Ci/Mole) has been synthetized and incubated with
the bacterial ribosome and its subunits. The results obtained show that this antibiotic has
two types of binding sites. The primary one is probably responsible for the inhibition of
protein synthesis whereas the secondary one is probably related to the misreading and reading
tiirough of the messenger RNA.

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Callipeltin A (1) is a cyclodepsipeptide from water sponge collected at New Caledonia. This compound shows anti-HIV and cytotoxic activities against KB and P388 cells and contains three new amino acid residues. β-methoxytyrosine (β-MeOTyr) (), (2R,R,S)--amino--guanidino-2,--dihydroxyheptanoic acid (AGDHE) (5), (S,R)-,-dimethyl-L-glutamine (diMeGln) (6). In addition, two new truncated open-chain derivatives of Callipeltin A (1), named Callipeltin D (2) and () were isolated. The unique structure and intriguing biological activities of this compound led us to explore total synthesis of Callipeltin A (1) and to elucidate stereochemistry of β-MeOTyr (). We started to synthesize Callipeltin () which contains β-MeOTyr (). In order to synthesize four stereoisomer of β-MeOTyr (), we attempted Evans anti or syn-Aldol reaction as a key step. Evans direct anti-aldol reaction with chiral benzyloxazolidinones () and p-hydroxy benzaldehyde (9) promoted by catalytic amounts of MgCl_2 in the presence of triethylamine and chlorotrimethylsilane. This proceder provide :1 diastereoselelctivity and 70% yield of isolated anti-aldol product (10). And Enolizalion of isocyanate oxazolidinone (13) with di-n-butylboryl trifrate and diisopropylethylamine followed by treatment with aldehyde afford syn-aldol product 14 affording 88% yield and 1:5 anti: sin diastereomeric ratio. On the other hand, we tried Sharpless Asymmetric dihydroxylation () and Aminohydroxylation () to give all four stereoisomers of β-MeOTyr. Treatment of olefin (18) with -mix α provided diol (19) and the α position alcohol of 19 was converted to sulfone regioselectively followed by azidation and treatment of 20 with PPh_ to afford aziridine (21). Addition of aziridine (21) and _・Et_2O in methanol produced α-amino β-methoxy adduct (). reaction protocol with t-butylcarbamate was successfully applied to afford desired in single step. Now we construct Callipeltin to determine absolute stereochemistry of β-MeOTyr (). In addition, we report the synthesis of diMeGln (6) and (2R,R,S)--hydroxy-2--6-trimethyl hepanoic acid ().

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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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The phase diagrams of the Ni-Mo- and Ni-W- ternary systems in the region of less than 50mol% were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
:L (1365K, 71.5mol%Ni-6.mol%Mo-.5mol%)=(Ni)++
:L (1355K, 62.5mol%Ni-2.5mol%Mo-30.5mol%)=++
:L (1445K, 42.mol%Ni-30.6mol%Mo-10.mol%)=(Ni)+NiMo+
P₁:L (1812K, 34.9mol%Ni-42.mol%Mo-.mol%)+MoB=+
P₂:L (1633K, 42.mol%Ni-40.mol%Mo-17.mol%)+Mo=+
:L (1812K, 53.5mol%Ni-33.mol%Mo-12.mol%)+Mo=NiMo+
:L (1622K, 51.mol%Ni-31.6mol%W-17.mol%)=(Ni)+W+
:L (1260K, 71.mol%Ni-.mol%W-.mol%)=(Ni)++
:L (1291K, 65.mol%Ni-.mol%W-29.mol%)=++
P₁:L (2115K, 23.mol%Ni-43.1mol%W-33.1mol%)+WB=+
P₂:L (1657K, 48.9mol%Ni-33.1mol%W-18.mol%)+=W+
The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.

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