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AbstractLaser–plasma interaction and hot electrons have been characterized in detail in laser irradiation conditions relevant for direct-drive inertial confinement fusion. The experiment was carried out at the Gekko XII laser facility in multibeam planar target geometry at an intensity of approximately $3\times {10}^{15}$ W/cm2. Experimental data suggest that high-energy electrons, with temperatures of 20–50 keV and conversion efficiencies of $\eta <1\%$ , were mainly produced by the damping of electron plasma waves driven by two-plasmon decay (TPD). Stimulated Raman scattering (SRS) is observed in a near-threshold growth regime, producing a reflectivity of approximately $0.01\%$ , and is well described by an analytical model accounting for the convective growth in independent speckles. The experiment reveals that both TPD and SRS are collectively driven by multiple beams, resulting in a more vigorous growth than that driven by single-beam laser intensity.

En la División de Estudios de Postgrado e Investigación de la Universidad Nacional Autónoma de México, en el Departamento de Ortodoncia, nosotros desarrollamos diferentes métodos analíticos y descriptivos, donde se realizó estudio estadístico de la clasificación esqueletal con una muestra de 428 pacientes que recibieron tratamiento de ortodoncia. Se seleccionaron personas entre 8 y 40 años de edad. Se capturaron datos de acuerdo a sexo, edad y maloclusión esqueletal para conocer el panorama epidemiológico. Después del análisis estadístico encontramos que el 53.3% de la muestra se encontraba, en clase I esqueletal, que el 64.7% era del sexo femenino y que el 52.08% se encontraba en el rango de edad de 13 a 19 años, además de otros datos.

A two-dimensional (2D) beam imaging system with a fluorescent intensifying screen and high-speed charge-coupled device (CCD) camera was developed to observe the fluctuations of the beam position and size. This system can perform imaging of the beam spot and the calculation of both its position and size from the obtained image with a cycle-time of 20 ms. For quality assurance of scanned carbon-ion therapy, we measured the stability of the unscanned-beam position and size by using this system at the isocenter in a treatment room. We confirmed that the fluctuation ranges of its position and size were less than the tolerance for scanning irradiation.

Dy-Ba-Cu-O bulk superconductor has an excellent capability of trapping magnetic flux and lower heat conductivity at cryogenic temperatures as compared with Y-Ba-Cu-O bulk superconductor. The Young's modulus and the bending strength in the range from room temperature to 7 K were measured by the three-point bending tests using specimens cut from a melt-processed Dy-Ba-Cu-O bulk superconductor. They were tested in a helium gas flow type cryostat at Forschungszentrum Karlsruhe and in a liquid nitrogen bath at Iwate University. The Young's modulus was calculated by either the slope of stress-strain curve or that of the load-deflection curve of the specimen. Although the bending strength measured in the two institutes coincided well, there was a significant discrepancy in the Young's modulus. The Young's modulus and bending strength increased with decrease of temperature down to 7 K. The amount of increase in the Young's modulus and the bending strength were about 32% and 36% of those at room temperature, respectively. The scatter of data for each run was significant and did not depend on temperature. The temperature dependence of the Young's modulus coincided with that in Y-Ba-Cu-O obtained by ultrasonic velocity. The temperature dependence of the Young's modulus and the bending strength was discussed from the view point of interatomic distance of the bulk crystal.

Rare earth based bulk superconductors originally have many voids and cracks. Thus their ultimate tensile strengths are not material constants but apparent ones depending on the voids and cracks in each bulk. In this study, based on the observations of the surface of the actual specimens, artificial samples with voids were generated for numerical stress calculations. The sizes of voids in an artificial specimen were assumed by the probability distribution function expressing the results of the observations, while the locations of voids were randomly assumed. Numerical calculations were repeatedly conducted to obtain the statistical results of the stress concentration factors around voids. The scatter of experimental strength and Young's modulus among the specimens having linear stress-strain curves can be predicted by the evaluations proposed in this study.

Core−shell colloids, particles covered with polyelectrolyte (PE) multilayer films and lipid bilayer membranes, were prepared through self-assembly processes. The PE multilayer films were fabricated by the layer-by-layer (LbL) assembly of poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrenesulfonate) (PSS) onto colloidal particles. The inorganic-based synthetic lipid, N-[N-(3-triethoxysilyl)propylsuccinamoyl]dihexadecylamine (Si-lipid), was employed for membrane formation and was deposited onto the PE-coated particles through electrostatic interaction. The naturally occurring lipid, dimyristoylphosphatidic acid, sodium salt (DMPA), was also used for comparison. Multilayer film buildup on the particles was monitored stepwise by microelectrophoresis, and formation of the lipid bilayers was confirmed by fluorescence microscopy as well as scanning and transmission electron microscopy. The morphological stability of the Si-lipid and DMPA membranes to the surfactant Triton X-100 and ethanol was examined by fluorescence measurements. The Si-lipid bilayer coating was found to be highly stable upon exposure to Triton X-100 and ethanol solutions, even at high concentrations, whereas the DMPA membranes delaminated from the particle surface at low surfactant concentrations and low ethanol content aqueous solutions. The enhanced stability of the Si-lipid film is attributed to the polymerized moiety in the headgroup of the synthetic lipids and H-bonding interactions between adjacent Si-lipid molecules. The Si-lipid systems described here are attractive because of the potential to prepare robust inorganic lipid-based films with controllable properties, for example, thickness, permeability, and stability, both in the form of coatings on particles and as capsular colloids.

We report the preparation of aqueous liposome dispersions of J-aggregates formed by the amphiphilic merocyanine dye (MD). A series of liposome-forming lipids were dispersed together with MD J-aggregates at different molar ratios of MD to lipid. The MD J-aggregate dispersions prepared with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at the MD to DMPC ratio of 0.16 exhibit good dispersibility; that is, they can be readily redispersed without any flocculation even after their precipitation. By use of different counterions for the MD molecules, two types of J-aggregate dispersions, one that exhibits an absorption band (J-band) at 635 nm (type I) and the other at 600 nm (type II), were obtained. As an example of the use of MD J-aggregates liposome dispersions, the thermochromic transformation of MD J-aggregates was demonstrated. When the dispersions are heated, J-aggregates of type I transformed into type II at a certain temperature (Tdisp). The parameters that control the speed of the transformation and the value of Tdisp were determined.

Ag-added Y–Ba–Cu–O bulk superconductors were joined using Ag-added Er–Ba–Cu–O solder and different Er211 contents. Microstructural analysis revealed that the volume fraction of Er211 at the joint with a composition of Er123:Er211 = 4:1 was the same as that for the expected volume fraction of the initial composition. That is, this composition seems to be optimum, since the mass balance was maintained during the crystal growth from the initial growth stage to the final stage. The trapped-field distribution for the joint using this composition was uniform and the only single peak indicated that strong coupling was achieved.

We examined the effects of IGF-I (1–1000ng/ml) on cell proliferation in LM2d6 mouse fibroblast cells at 0.1, 1.0 and 5.0% fetal bovine serum (FBS). In medium containing 0.1% FBS, treatment of LM2d6 cells with IGF-I significantly reduced the cell number in a dose- and time-dependent manner, whereas no effects were seen at 1 or 5% FBS. Treatment of the cells with 0.1% FBS for 72h caused DNA laddering and nuclear condensation. However, Scatchard analysis for IGF-I binding sites on the cells revealed that both the number and the affinity of IGF-I receptors were not greater than that of Balb/3T3 cells. Furthermore, the apoptotic action of Long (R3)-IGF-I, an analogue of IGF-I that has a reduced affinity for IGF binding proteins, was not greater than that of IGF-I. Taken together, we conclude that IGF-I reduces cell proliferation at low levels of FBS due to the induction of apoptosis. This effect is probably not caused by an excess production of IGF binding proteins in LM2d6 cells.

Mice were fed a diet supplemented either with beef tallow (BT), BT plus ethyl eicosapentaenoate (EPA) or BT plus ethyl docosahexaenoate (DHA) for 9 weeks. EPA and DHA supplementation increased the content of the respective fatty acid in spleen leukocyte lipids, which was associated with the reduction in the arachidonate content. IL-1β mRNA induction upon lipopolysaccharide (LPS) stimulation in spleen leukocytes in the DHA diet group was significantly lower than in the BT diet group, but the EPA diet was without any significant effect. The amount of prostaglandin E2 (PGE2) released from LPS-stimulated spleen leukocytes was significantly lower in both the EPA and DHA groups than in the BT group. Thus, dietary EPA and DHA inhibited arachidonate metabolism similarly but had different effects on IL-1β mRNA induction in mouse spleen leukocytes.

This paper is concerned with the interaction between the applied magnetic field and the magnetic fluid surface. Liquid responses of magnetic fluids under the magnetic and vibrating fields were investigated. Experiments were performed on a vibration-testing system which provided lateral and longitudinal excitation. The effect of the magnetic field gradient on liquid surface motion in an open circular cylindrical tank was noted. Details of surface responses of a magnetic fluid in the cylindrical container excited longitudinally under an applied magnetic field were revealed. Some similarities and differences between single magnetic spike oscillation and the symmetric free surface mode (0, 1) of magnetic liquid sloshing in the presence of a magnetic field were investigated. It was found that the elongation of the symmetric free surface mode (0, 1) and single magnetic spike were based on the same mechanism. The formation and the disappearance of magnetic drops formed by surface disintegration in the cylindrical container subject to horizontal vibration were also investigated. It was observed that the number of floating drops induced by vibrating the cylindrical container laterally with the natural frequency of the fluid-container system, decreased greatly with the magnetic field intensity.

This paper describes an experimental study of the dynamic behavior of magnetic fluid jets which are injected from a vibrating nozzle into the atmosphere. It was found that an intact liquid jet can be made to bifurcate continuously into a pronged jet by vibrating the nozzle with certain combinations of frequency and acceleration. The effects of the magnetic fields on the drops produced by the jet breakup are also revealed.

The impact phenomena between a magnetic fluid drop and paper on the hard rubber mat, subject to a magnetic field, have been investigated. Effects of a magnetic field on the spread area of a magnetic drop and on the velocity of radial flow were revealed with a three-dimensional motion analysis system.

Scanning and transmission electron microscopy has been used to examine the fracture surface topography and the dislocation structure of 70:30 brass and copper in order to study the mechanisms of Stage II fatigue crack growth. In the early period of Stage II growth the fracture surfaces lay mainly in crystallographic planes, the crystallographic features in fractographs being more pronounced in brass than in copper. Beneath the fracture surfaces, there were observed dislocation arrays densely packed in the slip planes in brass and the well developed cells in copper. In the late period of Stage II growth, however, fine contrast of indistinct shape was observed just beneath the striations on fracture surfaces in both the metal and the alloy. Outside such regions, however, numerous twin bands were observed in brass and in the elongated cells in copper. It appears that in the later period of Stage II cracks grow by means of an opening and closing behaviour which is unaffected by their crystallographic orientations.

Abstract—The effects of bluing, associated with drawing strain, on the fatigue strength of eutectoid steel wires have been investigated. The fatigue limit increases by bluing and the increase is more significant with higher drawing strain. The peak in the fatigue limit with regard to the drawing strain in the wires, at a strain of 2.5, disappears after bluing. On the other hand, in the ferritic steel wires investigated for comparison, the fatigue limit gradually increases with the drawing strain up to 7.7. Furthermore, no appreciable change in the fatigue limit due to bluing is found. Based on the results of hardness tests on fatigue specimens with‐ and without‐bluing, it is deduced that the decrease of the fatigue limit beyond the peak drawing strain in the eutectoid steel wire can partly be attributed to insufficient locking of the high‐density dislocations by solute atoms. The effect of relaxation of residual stress during bluing is also briefly discussed.

The effects of ursodeoxycholate administration on the biliary excretion of the antibiotics cefotiam and sulbenicillin were studied in five patients with stable hepatic function receiving percutaneous transhepatic biliary drainage for obstructive jaundice. Cefotiam (I g) and sulbenicillin (2 g) were administered intravenously before and after ursodeoxycholate administration, and the maximum concentrations of the antibiotics in the bile and total amounts excreted in the bile during the 4 h after administration were determined. After ursodeoxycholate administration, both the maximum concentration of cefotiam in the bile and the amount excreted increased significantly. Ursodeoxycholate also increased the peak concentration and total excretion of sulbenicillin. For both cefotiam and sulbenicillin, the amount of antibiotic excreted in the bile during the 4 h after administration showed a significant correlation with the amount of bile acids excreted in the bile. This strongly suggests a common mechanism for the biliary excretion of these antibiotics and bile acids. Ursodeoxycholate administration is a benign way to increase both the concentration and the total amount of antibiotic excreted in the bile. Therefore, it may be useful in the treatment of serious biliary tract infections, especially in patients receiving biliary drainage.

Two substrains derived from an uncloned 71st embryo (E7)) passage and a cloned 71st embryo-10th chick embryo kidney cell (E71CEK10) passage of the Beaudette strain of avian infectious bronchitis virus were back-passaged through organ cultures of chick embryo trachea. The organ culture-passaged viruses had altered biological properties such as absence of or delayed lethality for chick embryos and lack or diminution of plaque-forming ability in chick embryo kidney monolayers but they showed no clear change of pathogenicity for 3-week-old chickens. These viruses regained their lethality for chick embryos, their cytopathic effects, and their plaque-forming ability in chick embryo kidney cells after they had been back-passaged through chick embryos, depending on the passage number.The results of cross neutralisation tests using the constant serum-variable virus method in chick embryos indicated little antigenic difference between the original virus and various host-passaged derivative strains.

A 15-inch diagonal size digital full color FLCD has been developed. It has 1024 × 768 pixels and each pixels is divided into 12 sub-pixels in order to realize 4,096 colors/pixel with the optical center of illumination maintained. Additionally using the so-called, dither techniques, it has demonstrated that the 16 million different hues are achievable even with the bistable FLC.

The human promyelocytic leukemia cell line HL-60 can be induced to differentiate toward neutrophils and subsequently die via apoptosis in vitro. In this paper, we investigated the roles of protein-tyrosine kinases (PTKs) in retinoic acid (RA)-induced granulocytic differentiation of HL-60 cells. Accompanying the RA-induced differentiation, activities of src family PTKs Lyn and Fgr became detected and reached a plateau 2 days after the stimulation. The immunoblotting using anti-phosphotyrosine antibody (PY-20) showed that the proteins of 56 and 53 kDa were predominantly tyrosine-phosphorylated at day 2. Adsorption and immunoprecipitation of the cell lysate by specific antibodies evidenced that these phosphotyrosine-containing proteins are Lyn and Fgr PTKs. The degree of both activities and tyrosine phosphorylation of these PTKs was reduced to be minimal at day 5 when the HL-60 cells start to die by apoptosis. The inhibitors of PTKs, herbimycin A and genistein, were demonstrated to cause premature cell death of HL-60 cells in the presence of RA. The death was the consequence of an apoptotic process. The Ra-treated HL-60 cells, when incubated with specific c-lyn or c-fgr antisense oligodeoxynucleotide, also underwent premature death at day 2. These data implicate that Lyn and Fgr PTKs prevent programmed cell death to promote granulocytic differentiation of HL-60 cells.

This study was performed to investigate sequential changes in bile secretion and biliary lipids after taurocholic acid (TCA) loading of regenerating rat liver. TCA was administered intravenously at stepwise-increasing doses to groups of non-operated control and partially hepatectomized rats, 24, 72 and 168 h after surgery. Bile flow, bile-acid output (BAO) and phospholipid output (PLO) (expressed per gram of liver) in partially hepatectomized rats increased more than in the controls. Using an isolated perfusion rat-liver system, TCA infusion was also carried out on groups of non-operated control and hepatectomized rats 72 h after operation. Again bile flow, BAO and PLO (expressed per gram of liver) were significantly higher in the partial hepatectomy case, mirroring the results obtained in vivo. When horseradish peroxidase (HRP) was pulse-loaded in isolated perfusion preparations, the second peak of biliary HRP secretion in hepatectomized rats was significantly higher than in controls. We conclude that increased bile-acid flow in partially hepatectomized rats is dependent upon acceleration of vesicular transport accompanying or following proliferation in regenerating livers.

In this study, it was shown that the proportion of guanosine triphosphate (GTP)-bound active Ras increased in TPA (12-o- tetradecanoyl phorbol-13-acetate)-induced monocytic differentiation of HL-60 cells. The increase of active Ras was observed at 24 hours after TPA stimulation and attained to threefold (15%) over the proportion in nontreated HL-60 cells. Herbimycin A, an inhibitor of tyrosine kinase, prevented the activation of Ras, as well as the induction of monocytic differentiation. In parallel with the activation of Ras, the proteins with molecular weights of 52, 56, 62, and 190 kD were tyrosine- phosphorylated and formed a complex with GTPase-activating protein (GAP) for Ras. In addition to the 116-kD GAP (type I GAP), the 100-kD GAP (type II GAP) molecule was markedly induced at 24 hours after TPA stimulation of HL-60 cells. These phenomena sustained for a further 24 hours during monocytic differentiation. However, they were not observed during retinoic acid-induced granulocytic differentiation of the cells. The HL-60 transfectants, which expressed a dominant inhibitory Ha-ras Asn17, showed a low level of tyrosine-phosphorylated GAP-associated proteins and did not undergo full differentiation in response to TPA. Taken together, these data indicate that the activation of Ras and GAP complex formation mutually correlate and function downstream of protein- tyrosine kinases in the signaling pathway for monocytic differentiation of HL-60 cells.

Abstract: Observations of dislocation structures around the fatigue cracks in the early stage in polycrystalline copper were made through an ultrahigh voltage electron microscope operating at 2000 kV. Ladder like structures and initial cracks within them were fre-quently observed. These dislocation structures were formed prior to the crack initia-tion, and the crack was initiated and propagated within these structures accompanied by no appreciable dislocation entanglements in the earliest stage. On the other hand, cell structures were observed around the cracks which appeared to have grown into the sub-sequent stage (the stage between Stages I and II). Cell size ahead of the crack tip was not so small, and it seemed that the crack was able to propagate across the cells. On the basis of these observations, the mechanisms of fatigue crack initiation and propagation in the early stage in copper bulk-specimens are briefly discussed.

Abstract: Transfer parameters for dose assessment such as deposition velocity (V g), fraction of directly deposited on plants to the edible parts (r) and transfer factors (B iv) have been evaluated. Deposition velocity under drying and wet conditions was evaluated about 0.8 cm/s. Fraction of directly deposited on plants and transfer factors in plants showed a lognormal distribution. Geometric means of fraction of deposited in rice, leafy vegetable and grass were <9·10–3, 0.2 and about 9·10–2, respectively. Geometric mean of the transfer factor in leafy vegetable was about 3·10–2. These results were compared with the parameters given in the US NRC Regulatory Guide and previous literature values. The results showed that the fraction of directly deposited on plants were smaller than the recommended value in the NRC Regulatory Guide. They also showed that the deposition velocity and transfer factors were almost similar to the results reported in the literature.

Hoshino M, Ohiwa T, Hayakawa T, Kamiya Y, Tanaka A, Hirano A, Kumai T, Katagiri K, Miyaji M, Takeuchi T. Effects of dibutyryl cyclic AMP and papaverine on intrahepatocytic bile acid transport. Role of vesicle transport, Scand J Gastroenterol 1993;28:833-838.The secondary messenger cyclic AMP plays an important role in regulating biliary excretory function by stimulating the transcytotic vesicle transport system, whereas papaverine exerts an inhibitory effect on this system. We therefore investigated their effects on bile acid-induced cytotoxicity and intrahepatocytic content of bile acid in primary cultured rat hepatocytes. Simultaneous addition of 1 mM dibutyryl cyclic AMP (DBcAMP), an analogue of cAMP, with 1 mM taurochenodeoxycholic acid (TCDCA) significantly decreased the release of lactate dehydrogenase (LDH) as compared with the case with 1 mM TCDCA alone (7.1 ± 0.13% of total versus 10.7 ± 0.3%). In contrast, 0.1 mM papaverine approximately doubled the amount of LDH (22.0± 0.6% of total versus 10.7± 0.3%; P < 0.01). The intracellular content of TCDCA 180 min after the administration of 1 mM TCDCA alone was 20.8± 0.7 nmol/mg protein, that after simultaneous administration of 1 mM DBcAMP, 16.2 ± 1.0 nmol/mg protein, and that after the simultaneous administration of 0.1 mM papaverine, 38.5 ± 1.9 nmol/mg protein. A clear correlation between the release of LDH from hepatocytes and the intracellular content of TCDCA was thus observed. When given together with 1 mM taurocholic acid (TCA) or 1 mM tauroursodeoxycholic acid (TUDCA), papaverine exerted little effect on cytotoxicity or intrahepatocytic bile acid content. When cells were bathed in a medium free of bile acid after pretreatment with 1 mM TCDCA and 1 mM DBcAMP, additional exposure to DBcAMP for 30 min significantly stimulated reduction of intracellular TCDCA content (30.2± 0.4% of total versus 44.0 ± 1.4%). The opposite effect was observed for 0.1 mM papaverine, with bile acid content being significantly increased (68.5 ± 5.9% of total versus 39.7± 0.4%). These findings indicate that bile acid-induced hepatotoxicity is actually dependent on intracellular content and that a vesicular pathway is involved in intrahepatocytic transport of more hydrophobic bile acids such as TCDCA.

Activation of integrin and organization of cytoskeletal proteins are highly regulated in cell adhesion and aggregation. The interaction of leukocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecules-1 (ICAM-1) mediates cell adhesion and aggregation, which facilitate leukocyte trafficking to inflamed tissues and augment effector functions. We investigated how LFA-1/ICAM-1-mediated adhesion and aggregation are regulated in HL-60 cells induced to differentiate into neutrophils by retinoic acid (RA). Uninduced HL-60 cells did not bind to ICAM-1 even with stimulation by 12–0-tetradecanoyl phorbol-13- acetate, although they express LFA-1 on the cell surface. When cultured with RA for 24 hours, HL-60 cells were able to adhere to ICAM-1 constitutively. The induction of adhesion did not accompany any change in surface density of LFA-1, indicating that the avidity of LFA-1 was increased. The change in its avidity required de novo synthesis of proteins. Although ICAM-1 was intensely expressed on RA-induced HL-60 cells, these cells did not show any cellular aggregation. The HL-60 cells transfected with the active form of Ras (Val12) exhibited LFA- 1/ICAM-1-dependent aggregation by RA stimulation without change in the avidity of LFA-1. In these Ras-transfectants, a cytoskeletal protein, paxillin, was tyrosine-phosphorylated, and the level of F-actin increased. Transforming growth factor (TGF) beta, as well as cytochalasin D, prevented both the tyrosine phosphorylation of paxillin and the aggregation without any effects on the avidity of LFA-1. Thus, an increase in the avidity of LFA-1 was not sufficient for the induction of aggregation, which required activation of Ras and reorganization of cytoskeletal proteins. These results suggest that distinct regulatory mechanisms control LFA-1/ICAM-1-dependent adhesion and aggregation in HL-60 cells differentiating into neutrophils.