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The electric plasma discharge method involves the application of a voltage between a cathode and anode in a conductive electrolytic solution to create a discharge plasma at the cathode. When certain material is used as the cathode, small droplets are emitted with the plasma discharge, and the melted droplets are rapidly cooled in the solution to form nanoscale particles of the material. In this work, nanoparticles of Al, Au, Si, and various alloys of between 100 nm and less than 10 nm in size were produced and characterized. Characterization of Si nanoparticles is especially important because their use in lithium batteries greatly influences battery performance. It was found by high resolution electron microscopy and microstructural surface analysis that oxidation layers of a few nm in thickness were formed on the surface of the Si nanoparticles.

Deformation behavior of Nb–Si–Zr alloys is investigated at various temperatures ranging from R.T. to 1670 K. The master alloy ingots composed of Nb–18.1 at% Si–1.5 at% Zr doped with Mg are Ar-arc-melted. The ingots contain Nb rods (radius: 1 μm) in Nb 3 Si matrix formed by eutectic reaction. Alloys are subjected to heat treatments at 1923 K for 4–100 h to obtain a large Nb network structure with small silicide (α-Nb 5 Si 3 ) particles by decomposing Nb 3 Si matrix into Nb and Nb 5 Si 3 through a eutectoid reaction. Compression tests are conducted at room temperature in air and at elevated temperatures in Ar atmosphere. At 1471 K the maximum strength is 500 MPa and compressive ductility is higher than 10% with a strain rate of 1.0 × 10 −4 s −1 , while at room temperature the maximum strength is over 1500 MPa and compressive ductility is about 1.5%. The high-temperature deformation obeys a power-law type equation. The stress exponent n is evaluated to be 4.8 and the apparent activation energy is 350 kJ/mol. The Vickers indentation at room temperature revealed that the crack propagation at room temperature is suppressed effectively by ductile Nb. This suggests that the Nb aggregate in the network structure acts as a large Nb grain containing fine Nb 5 Si 3 particles, which might be beneficial for ductility at low temperatures.

Mg-Y-Zn alloys have attracted much attention in recent years due to their excellent mechanical properties, which are said to be the effect of the intermediate phase (X phase) in the Mg solid solution (a phase). The formation behavior of the X phase has been reported to be a eutectic type reaction in the Mg-Y-Zn pseudo-binary system. However, the phase diagram of this system still requires clarification. In the present study, the 97.0Mg-1.3Zn-1.7Y (at%) alloy was prepared to clarify the liquidus and solidus in the liquid-solid coexistence region, and the solubility limit in the a phase. The chemical compositions of the alloy were analyzed by electron probe X-ray microanalysis after isothermal heat treatment. The results indicate that the Mg-Y-Zn ternary system can be represented as a pseudo-binary system between the a and X phases. In addition, the solidus line for the a phase has been clarified. The solubility limit for the a phase is not much different from that of the previous report, whereas the formation behavior of the X phase is not in the manner of a eutectic reaction, but rather that of a peritectic one.

Improvement of deformability for Mg-based composite materials with a dispersion of Ti particles has been considered in terms of the strain transfer through the interface, but is not fully understood during the deformation of ductile Ti particles. Mg-based composites composed of pure Mg and pure Ti plates was investigated to clarify the strain transfer through the Mg/Ti interface using crystallographic orientation analysis based on electron back-scattered diffraction (EBSD) patterns. It is suggested that the larger Schmid factor and lower residual strain energy (W) are significant for the operation of a prismatic slip system in the Ti grains.

Effect of rare-earth elements (Y and Dy) on the mechanical properties of Mg solid solution single crystal is investigated. Comparing with the effect of other elements reported by previous studies, the solid solution strengthening by Y and Dy are much higher than that of other additives such as Zn for basal slip operation, while the isotropic strain by Zn atoms is higher than those of Y and Dy. Strain-rate changing tests were conducted for a further understanding of the dislocation motion and it revealed that the activation volumes estimated for Mg alloys with Y and Dy are much smaller than that of Zn-added alloy, while the activation enthalpy is almost the same. It was confirmed that the high strengthening effect by Dy addition is also found by Y addition, while the elastic interaction based on neither isotropic or anisotropic distortion are sufficient to explain the origin of the strengthening effect by Y and Dy addition.

Ni3Al-based alloys possess good oxidation resistance, moderate room and high temperature strength and ductility. Introduction of Cr-carbide particles through a solidification route is attempted to provide higher hardness and wear resistance. The mechanical and physical properties are measured at room temperature for several alloys with various carbon concentrations up to 2.0 wt.%. Hardness and wear resistance as well as compressive strength increase with increasing carbon concentration, while bend ductility decreases. Adhesion between carbides and matrix phase is good, and cracks propagate mainly through carbides. The crystallographic orientation relationships between constituent phases are also attempted using electron back-scattering diffraction (EBSD) technique. The thermal conductivity is found to be less sensitive to the alloy composition.

Alloys based on Nb-silicides exhibit superior high temperature strength than the commercial nickel based superalloys. In order to improve the low-temperature ductility by microstructural control, authors have attempted to understand the nature of the eutectic and eutectoid reactions in Nb-rich portion of the Nb–Si binary system, especially the crystallographic orientation relationship among the phases using FESEM-EBSD. During the eutectic reaction it was found that Nb rods of about 1 μm in diameter having a certain crystallographic orientation disperse in Nb 3 Si matrix in a eutectic cell. Then, during the following heat treatment Nb 3 Si decomposes into a lamellar structure composed of Nb and α-Nb 5 Si 3 in a manner of eutectoid reaction. It is observed that eutectoid Nb plates tend to nucleate at the eutectic Nb rod because both of them have a similar crystallographic orientation, resulting in a network of Nb phase with fine α-Nb 5 Si 3 dispersoids. The Nb network may act as a large Nb grain which is expected to show better mechanical properties at both low and high temperatures. Both the reaction kinetics of the eutectoid decomposition of Nb 3 Si and the tendency of the Nb network formation are significantly affected by doping elements, which are attributed to the control of the interfacial energies among phases.

Various investigations have been attempted to improve the low temperature ductility of Nb-silicides by microstructural control while they show superior high temperature strength. Present authors have focused on the microstructure evolution through the eutectic and eutectoid reactions in Nb-rich portion of Nb-Si binary system, and with small amounts of additives (Zr or Mg) alloys large Nb grains with fine silicide (α-Nb 5 Si 3 ) particles have been obtained, which is attractive for high temperature use. For further understanding of this phenomenon, the present study has two objectives; one is to apply the advanced solidification technique for further microstructure control, and the other is to investigate the effect of co-existence of Zr and trace amount of Mg on the microstructure evolution during the eutectoid reaction in terms of the interfacial energy between phases. EBSD analysis revealed that uni-directionally solidified alloy show the same crystallographic orientation relationship (O.R.) between Nb and α-Nb 5 Si 3 with that in arc-melted alloy having the same composition. On the other hand, Mg-doped alloy containing Zr shows an O.R. which was not observed in previous works. This implies that Mg doping is effective to control the interfacial energy between Nb and α-Nb 5 Si 3 even in Nb-Si-Zr alloys. Two-step heat-treatment is found to be effective to obtain finer microstructure, and a further investigation on the controlling factors of eutectoid decomposition will provide a proper route to well-controlled microstructures.

Mechanical properties of L1 2 -Co 3 (A1,W) polycrystalline sample are investigated by compression testing at various temperature ranging from room temperature to 1193 K. It was found that at room temperature the 0.2% flow stress is 410 MPa and the compressive ductility is higher than 10%, whereas at 1193K the 0.2% flow stress is 382 MPa and the compressive ductility is about 10%. Two candidates for the reaction scheme of the Co-rich region of the Co-Al-W ternary phase diagram are proposed by combining the results of microstructure observation, X-ray diffractometry and the previous report.

Introduction: High serum levels of lipoprotein (a) (Lp(a)) are associated with adverse outcomes after acute myocardial infarction (AMI). Lp(a) exerts its atherogenic and thrombogenic properties, which suggests greater lipid component of plaque and thrombi at the culprit lesion of AMI with elevated Lp(a). The risk of coronary artery disease is increased with a threshold serum Lp(a) level of 25 mg/dl. Purpose: We sought to evaluate impact of Lp(a) on myocardial viability and left ventricular function after AMI. Methods: The study included 156 patients (66±10.7 yrs, mean±sd, men 122, LAD/LCX/RCA 80/16/60) with first AMI within 24 hours from the onset who underwent emergent PCI. Serum Lp(a) was measured at admission. Serum CPK values were measured at admission and at intervals of 4 hours. Peak CPK value was determined. Within 2 weeks, Tl/BMIPP SPECT was performed to measure perfusion-metabolism mismatch score, an indicator of viable myocardium, from each total defect score of Tl/BMIPP using 17-segment model and semiquantitative visual score (0:normal, to 4:no uptake). Left ventricular ejection fraction (LVEF) was measured by two-dimensional echocardiography (2D trace) within 1 week (baseline LVEF) and at 6 months to 1 year (follow-up LVEF). Results: The study patients were divided into the group with serum Lp(a)≧25mg/dl at admission (n=42, Lp(a) 44.0±19.4mg/dl) and the group with Lp(a) Conclusions: Elevated Lp(a) was associated with less myocardial viability and less LVEF recovery after AMI.

A phenomenological calculation of phase equilibria by combining the cluster variation method (CVM) with the Lennard-Jones-type (L-J-type) pairwise atomic interaction energies has been attempted for the Fe-Pd-Ni ternary system in order to examine the possibility of Ni as the substituting element for Pd. The calculated Ni content in an Fe-Pd-based L10 ordered phase at 863 K shows fairly good agreement with the experimental analysis performed for Fe-5Pd-5Ni alloy by energy-dispersive X-ray spectroscopy of a transmission electron microscope. The detailed calculation indicates that Ni is preferentially substituted in a Pd site in the L10-ordered phase, which can be interpreted by the Lennard-Jones-type pairwise potentials employed for the present study. It is concluded from the thermodynamic point of view that Ni is a promising candidate as the substituting element for Pd in an Fe-Pd-based L10 ordered phase.

Isotherms of the Ir-rich portion of the Ir–Al–X (X: V, Nb, Ta) systems composed of fcc-Ir solid solution ((Ir) ss ), Ir-based L1 2 intermetallic compounds Ir 3 X and B2–IrAl are presented as a second report of a series of investigations on the phase equilibria in the (Ir or Rh)–Al–X (X: Ti, Zr and Hf, or, V, Nb and Ta) ternary systems. In both Ir–Al–Nb and Ir–Al–Ta systems fcc/L1 2 /B2 three-phase equilibrium is found. In Ir–Al–V system, Ir solid solution and Ir 3 V have close compositions each other and fcc/L1 2 /B2 three-phase equilibrium is expected. No ternary compound is observed in all of the isotherms. Solid solubility of each phase is confirmed by chemical analysis by wavelength dispersive X-ray spectroscopy (WDS). The direction of the solubility lobe of L1 2 –Ir 3 X with Al addition is explained in terms of the nearest neighbor interactions. Liquidus surfaces are also established by taking into account the microstructure of as-cast alloys, differential thermal analysis (DTA) data, and the Ir–Al and the Ir–X binary phase diagrams reported previously.

The effect of Zr on the formation of Nb/Nb5Si3 lamellar microstructure by eutectoid decomposition reaction of Nb3Si is investigated. It has been shown that the kinetics of the eutectoid decomposition of high-temperature Nb3Si phase into Nb and Nb5Si3 phases are sluggish in the binary Nb-Si system and that they are enhanced by Zr additions. The time-temperature-transformation (TTT) diagram for the decomposition is experimentally determined and the acceleration of the reaction by small Zr addition of 1.5 at. pct is confirmed by comparison with the reported TTT curves of binary and ternary alloys containing Ti. The role of the ternary element on the decomposition kinetics is discussed in terms of crystallographic orientation relationships (ORs) and Zr distribution in the parent Nb3Si phase during solidification.

Investigation on the crystallographic orientation relationships among D022-Al3Ti, A15-Mo3Al and high temperature bcc phase consisting of an Al-Mo-Ti ternary alloy with an equi-axed two-phase structure was conducted by FESEM/EBSD analysis. The grains of intermetallic phases have certain crystallographic orientations each other, while the crystallographic orientation distributions become random after a high temperature deformation. This strongly suggests the grain boundary sliding and grain rotating govern the high temperature deformation, which is consistent with the fact that the strain-rate sensitivity m is 0.3 or higher during a steady-state compressive deformation.

21 The advantage of using platinum (Pt) in industrial applications is due to its unique properties, such as its catalytic activity, high melting point (1), ductility (2, 3) and chemical inertness over a wide range of temperatures (4, 5). Platinum has been used for biomedical components, specialty chemicals, fuel cells and for pollution control catalysts, such as in automobile exhausts, as well as for jewellery, thermocouples and the cathodic protection of ships’ hulls (3). One typical application of platinum is in electronics devices, with thick film conductors being among the major products (6). Alloying elements, selected from the platinum group metals and noble metals, are usually employed to help develop higher strength or to protect a surface against deleterious service conditions (3). However, the addition of an alloying element may degrade the conductivity. Until now, the data available on the conduction properties of platinum alloys have been limited (7–12). This present investigation will survey the parameters of thermal conductivity in various platinum alloys at high temperatures. First, the composition dependence of thermal conductivity will be investigated and the results will be ordered according to the Periodic Table; second, the effect of work hardening will be investigated; and third, the temperature dependence of thermal conductivity will be surveyed.

Thermal conductivity and thermal expansion for Ir3X (X=Ti, Zr, Hf, V, Nb, Ta) were measured in the temperature range between 300 and 1100 K. The thermal conductivities of Ir3X are distributed in the range from 41 to 99 W m−1 K−1 at 300 K, while the difference of thermal conductivities becomes less emphasized at higher temperatures. The coefficients of thermal expansion (CTEs) of Ir3X are insensitive to temperature, which fall around 8×10−6 K−1 at 800 K.

Thermal conductivity and thermal expansion were measured for the L1 2 intermetallic compounds Rh 3 X (X=Ti, Zr, Hf, V, Nb, Ta) in the temperature range between 300 and 1100 K to evaluate the feasibility of applying the compounds to high temperature structural materials. The thermal conductivities of Rh 3 X are widely distributed in the range from 32 to 103 W m −1 K −1 at 300 K, while the difference of the thermal conductivities becomes less emphasized at higher temperatures. A trend is observed that the thermal conductivity of Rh 3 X is larger when the constituent X belongs to group 5 rather than 4 in the periodic table. The coefficients of thermal expansion (CTE) of Rh 3 X slightly increase with increasing temperature, and they are concentrated around 10×10 −6 K −1 at 800 K. A trend is that the CTE of Rh 3 X is reduced as the position of X goes downward in the periodic table. It is demonstrated that Rh 3 Nb and Rh 3 Ta are suitable for high temperature structural applications due to the larger thermal conductivities and the smaller CTE.

Thermal conductivity is one of the key parameters required for high-temperature structural applications of metallic materials. In this overview, the thermal conductivity of intermetallic compounds are extensively described based mainly on our past works, since there had been less works in this research field. Emphasis is placed on the B2 and the L12 compounds with metallic bonding such as NiAl, Ni3Al, etc., which have been attracting attention for engineering applications at higher temperatures. The thermal conductivity data have been accumulated for the intermetallic compounds, and the phenomenological aspects are reviewed in detail as a function of alloy composition, constituent and temperature. The Wiedemann-Franz law is applicable to the intermetallic compounds, indicating that the carrier of thermal conduction is an electron rather than a phonon. The thermal conductivity of an intermetallic compound with the ordered crystal structure is characterized as an enhancement due to ordering with reference to the basic contribution of solid solution with the disordered crystal structure. It is demonstrated that the thermal conductivity of intermetallic compounds is reduced by the addition of a third element, and this subject is also covered.

A contour map of thermal conductivity in a ternary intermetallic phase characterizes the direction of the contour ridge, and the ridge direction has been demonstrated to be a reliable indication of site preference of ternary elements in an intermetallic compound. Site preferences of fifteen kinds of ternary elements in NiAl are determined from the ridge direction of thermal conductivity contours in ternary β phase. It is found that V, Nb, Ta, Mo, Fe, Ru, Co and Pt substitute preferentially for nickel, while Ti, Mn, Ga, Si and Ge for aluminum, and Cr and Cu occupy both nickel and aluminum sites.

The direction of ridge of thermal conductivity contours in a ternary γ′-Ni 3 Al phase agrees with that of solubility lobe of γ′ phase in a ternary phase diagram. The classification of third elements based on the ridge direction does not always agree between ternary Ni 3 Al and NiAl phases.

A method for the determination of site preference of substitutional elements in intermetallic compounds is proposed. It is demonstrated in Ni3Al–X alloys that the ridge direction in thermal conductivity contours in the ternary γ′ phase agrees with that of the solubility lobe of the γ′ phase in ternary phase diagrams. The ridge direction is a reliable indication of site preference of substitutional elements in intermetallic compounds. The present method is conveniently applied to a normal polycrystalline specimen with small size, and therefore, a versatile class of brittle compounds can be studied.

Ternary addition generally degrades an excellent conduction properties of NiAl. The contour map of thermal conductivity in NiAl–X β single phase field is drawn for the ternary elements X=Ti, Cu and Ge. It is revealed that each element has a characteristic ridge direction in the contour map. This feature is discussed based on the preference substitutional site of a ternary element, and eighteen ternary elements with a sufficient solubility into NiAl are classified into three groups according to the ridge direction. Thermal conductivity of NiAl-based alloys increases with increasing temperature, however the ridge direction in the contour map remains unchanged.

Thermal conductivity of Pt alloys with an fcc single phase was comprehensively surveyed by employing the laser flash method. Thermal conductivity is dominantly determined by alloy composition and temperature and is scarcely influenced by fabrication condition. An addition of solute definitely decreases the thermal conductivity of Pt, and the conductivity-composition relationship is characterized by a sharp maximum at pure Pt. The Wiedemann-Franz relation held for Pt alloys suggests the dominant carrier of thermal conduction is an electron. An empirical rule is proposed that the thermal conductivity decreases significantly as the position of the solute element in the periodic table becomes horizontally more distant from that of Pt. Thermal conductivity of Pt alloys increases with increasing temperature in a range between 300–1100 K, and the temperature coefficient is found to be inversely correlated with the thermal conductivity.

症例は58歳の男性.左肩甲部腫瘤を主訴に当院整形外科に入院し, 生検で転移性腫瘍と診断された.術前CTで下部食道壁の肥厚を, 内視鏡検査で下部食道癌と診断された.左肩甲部腫瘤に対し整形外科で肩甲帯遊離術を施行.腫瘍は肩甲骨下の筋肉内に存在し, 病理は低分化扁平上皮癌であった.2か月後, EiEaの食道癌に対して, 右開胸開腹胸部食道切除術, 2領域郭清, 亜全胃管胸骨後再建術を施行した.術後経過良好であったが, 6か月目に脳転移で再発した.病理組織は類基底細胞癌, a2, v2, ly0, n2であった.類基底細胞癌は本邦で30例の報告があるが, 本症例は筋肉転移を来した.きわめてまれな症例であると思われた.

Thermal conductivities are measured for a series of Ni 3 X and Pt 3 X compounds in which an ordered L1 2 and f.c.c. disordered structures are formed when the constituent X belongs to the first long period in the periodic table. An empirical rule is found for both ordered and disordered structures that the thermal conductivity tends to decrease as the distance of the constituent X increases in the horizontal direction from the location of Ni and Pt in the periodic table. This trend is quite isomorphic with that of dilute solid solutions of Ni-X or Pt-X, although the magnitude is different. For most Ni 3 X and Pt 3 X compounds, thermal conductivity increases with increasing temperature. The temperature coefficient of thermal conductivity is higher in the disordered compounds than in the ordered compounds.

Thermal conductivity in nickel solid solutions with a γ single phase was comprehensively surveyed. The major findings are summarized as follows: First, alloying definitely decreases the thermal conductivity of nickel. The relationship between thermal conductivity and concentration in the dilute solid solution is characterized by the Nordheim relation. Second, for most solutes, the thermal conductivity of nickel alloys decreases significantly as the position of the solute element becomes horizontally more distant from nickel in the periodic table, which is equivalent to the Norbury–Linde rule of electrical resistivity. Third, cold deformation has no significant influence on the thermal conductivity of nickel alloys. Fourth, a monotonic increase in thermal conductivity as a function of temperature is observed in highly concentrated nickel alloys, while the thermal conductivity of dilute nickel alloys shows a minimum at the Curie temperature.

Thermal conductivity of A 3 B intermetallic compounds, where A denotes iron or nickel and B denotes group IIIb or IVb elements, is investigated by a laser-flash method. Among six kinds of L1 2 compounds, the largest thermal conductivity observed is 32 8 Wm −1 K −1 of Ni 3 Ga. In Fe 3 Ga and Fe 3 Ge, three polymorphs, i.e. L1 2 , D0 19 and D0 3 , can be achieved by performing a suitable heat treatment. Thermal conductivity of the D0 19 phase is quite close to that of the L1 2 phase, while the DO, phase shows smaller values. In most A 3 B compounds, the measured thermal conductivities tend to decrease as the position of constituent B becomes horizontally more distant from that of constituent A in the periodic table.

Results are given of comprehensive measurements on thermal conductivity of Heusler type intermetallic compounds Fe 2 AlTi, Co 2 AlTi, Ni 2 AlTi, Ni 2 GaTi, Ni 2 AlZr and Ni 2 AlHf. The compounds have fully ordered L2 1 structure. There exists a wide single phase region of L2 1 in Ni-Al-Ti ternary alloy system. The contour map showing the magnitude of thermal conductivity is constructed in Ni 2 AlTi single phase region. The thermal conductivity in Ni 2 AlTi takes a maximum of 21.4 Wm -1 K -1 at stoichiometry which is much lower than that of NiAl having a B2 structure. By the deviation from stoichiometry, the thermal conductivity decreases in Heusler compounds. The magnitude of thermal conductivity in Fe 2 AlTi, CO 2 AlTi and Ni 2 AlTi are compared in connection with those of B2 aluminides (FeAl, CoAl, NiAl) and titanides (FeTi, CoTi, NiTi). Thermal conductivities in three kinds of Heusler compounds X 2 AlTi (X : Fe, Co, Ni) are almost the same value of approximately 20 Wm -1 K -1 . Ordering from B2 to L2 1 increases thermal conductivity in accord with the estimation by Nordheim relation. The magnitude of thermal conductivity in X 2 YZ Heusler compounds, including Ni 2 GaTi, Ni 2 AlZr and Ni 2 AlHf, is related to those of XY and XZ compounds having a B2 structure.

Thermal conductivity measurement by the laser-flash method adopted here is very suitable for intermetallic compounds, some of which are too brittle for preparing samples with good geometry. Thermal conductivity data at room temperature are presented in the series of aluminides, FeAl, CoAl and NiAl, titanides, FeTi, CoTi and NiTi, and gallides CoGa and NiGa, in order to reveal the role of 8A group elements of the first transition metal series. Thermal conductivity reaches a maximum at stoichiometry and decreases with deviations from stoichiometry on either side in most of these compounds. The largest thermal conductivities observed are 92 W m−1 K−1 of NiAl among the aluminides, 23 of NiGa among the gallides and 73 of FeTi among the titanides. It is discussed that the thermal conductivity is further reduced as the position of the partner components becomes distant from that of a host component.

vol. 83, pp. 593-600. 5. W.C. Jeong and K. Cho: J. Kor. Inst. Met. Mater., 1999, vol. 37, pp. 672-79. 6. N. Yoshinaga, K. Ushioda, and O. Akisue: Proc. Symp. on High Strength Sheet Steels for Automotive Industry, R. Pradhan, ed., ISS, Warrendale, PA, 1994, pp. 149-58. 7. T. Matsumoto, S. Hamanaka, T. Yamada, and T. Tanaka: Int. Forum for Physical Metallurgy of IF Steels, ISIJ, Tokyo, 1994, pp. 269-73. 8. Bainite Committee of Iron and Steel Institute of Japan, Atlas for Bainitic Microstructures, T. Araki et al., eds., ISIJ, Tokyo, 1992. 9. G. Krauss and S.W. Thompson: Iron Steel Inst. Jpn. Int., 1995, vol. 35, pp. 937-45.

E2 1 -Fe 3 AlC carbide (K) in the Fe-Al-C ternary system is known to have ductility at room temperature. It forms a lamellar structure similar to the pearlite with a ferrite (a) phase through a eutectoid-like reaction from an austenite (γ) phase and improved mechanical properties are expected by replacing cementite to K phase. The mechanical properties of a + K two-phase lamellar structure were investigated through micro-Vickers hardness measurements and compression tests at room temperature in order to compare with those of pearlite steels. A typical mean inter-lamellar spacing of Fe-8 at%Mn-13at%Al-7at%C alloy aged at 773 K for 100h was 60 nm and its yield stress and micro-Vickers hardness were 1880 MPa and 580 HV, respectively. Yield stress and micro-Vickers hardness of these specimens were higher than those of pearlite steels regardless of the mean inter-lamellar spacing. Those results seem to be rationalized by taking the solid solution hardening of ferrite phase into account.

Stem cell mobilization by granulocyte colony-stimulating factor (G-CSF) has been shown to enhance endothelial healing after spontaneous or iatrogenic arterial disruption. Granulocyte colony-stimulating factor treatment might attenuate endothelial dysfunction after sirolimus-eluting stent (SES) implantation that may be associated with adverse cardiac events during follow-up. This prospective, double-blind, randomized, placebo-controlled study investigated whether G-CSF improved endothelial dysfunction after SES implantation.One hundred patients who underwent SES implantation were randomly assigned to the G-CSF (n = 50) or the placebo group (n = 50). They received daily subcutaneous injection of 300 μg G-CSF or saline for 5 days. Endothelial function was estimated by measuring the coronary vasoreactivity in the segments 15 mm proximal and distal to SES in response to intracoronary infusion of acetylcholine (10(-8) and 10(-7) mol/L) at 9-month follow-up.Follow-up angiography was performed in 41 G-CSF patients (82%) and 46 placebo patients (92%) (P = .14). Changes in coronary diameter in response to acetylcholine infusion in the proximal segment were not significantly different between the 2 groups. However, vasoconstriction in the distal segment in response to 10(-8) mol/L (-3.9% ± 6.4% vs -7.0% ± 8.1%, P.05) and 10(-7) mol/L (-8.8% ± 11.0% vs -15.2% ± 7.6%, P.01) acetylcholine infusion was attenuated in the G-CSF group. Endothelium-independent vasodilatation after nitrate infusion did not differ between the 2 groups.Granulocyte colony-stimulating factor attenuates endothelial dysfunction after SES implantation.

In Japan, a lower maintenance dose of ticlopidine is used than in the United States and Europe. Therefore a lower maintenance dose of clopidogrel may also be considered appropriate in Japanese patients. The present randomized pilot study evaluated the efficacy and safety of 50 mg clopidogrel in Japanese patients who underwent drug-eluting stent (DES) implantation. A total of 200 patients with 277 lesions who underwent intravascular ultrasound-guided DES implantation were enrolled. The subjects were allocated to the 50- or 75-mg clopidogrel group. All patients received 100 mg aspirin daily before the procedure, and this continued indefinitely. The duration of clinical follow-up was 21.8 ± 5.7 months in the 75-mg group and 21.9 ± 6.1 months in the 50-mg group (P = 0.96). During follow-up, no cardiac death, myocardial infarction, or stent thrombosis was observed in either group. Side effects of clopidogrel were observed in 4 patients (4.0 %) in the 75-mg group and in 4 patients (4.0 %) in the 50-mg group. Following this randomized pilot study, it may be justified to perform a large-scale randomized study comparing 50- and 75-mg dosing of clopidogrel in Japanese patients undergoing coronary stent implantation.

A case of squamous cell carcinoma of the breast, which is regarded as squamous metaplasia with adenocarcinoma, is reported. A 42-year-old woman was seen at the hospital because of a tumor of the left breast and pain. Mammography and echography revealed a breast cancer. Modified radical mastectomy was carried out. Histologically, the tumor was squamous cell carcinoma and axillary lymph node involved squamous cell carcinoma mixing with adenocarcinoma cells. There was recurrence on the left breast skin one year after the operation. The skin biopsy was carried out. Histological examination revealed that the lesion was predominaly comprised of sold-tubular carcinoma cells, with scarce squamous cell components.

There is little information about the incidence of the side-effects of clopidogrel in Japanese patients undergoing coronary stent implantation. The present study included 334 consecutive patients who were given clopidogrel (75 mg daily) after coronary stent implantation. Aspirin (100 mg daily) was used indefinitely. Clopidogrel was prescribed for at least 4 weeks in patients with bare metal stents and indefinitely in those with drug-eluting stents (DES). The duration of clinical follow-up was 164.7 ± 139.0 days. Half of the patients underwent stenting because of acute myocardial infarction. DES were used in 38% of the patients. Definite early stent thrombosis occurred in one patient (0.31%). There was one definite late stent thrombosis (0.31%). Side-effects of the clopidogrel were observed in 16 patients (4.9%). Liver dysfunction occurred in seven patients (2.1%), skin rash in six (1.8%), and bleeding in three (0.9%). There was no neutropenia or thrombocytopenia. The results of this study show that prescribing clopidogrel as well as aspirin is a safe treatment for Japanese patients undergoing coronary stenting.

This study evaluated long-term safety and efficacy of low-dose (50-mg) clopidogrel in Japanese patients undergoing coronary stenting. A total of 126 patients with 153 lesions who consented to take a 50-mg maintenance dose of clopidogrel to prevent stent thrombosis were enrolled. The duration of clinical follow-up was 13.9 ± 9.7 months. There was one early stent thrombosis (0.65%). Neither late nor very late stent thrombosis was observed in patients on clopidogrel plus aspirin. Side effects of clopidogrel were observed in 9 patients (7.1%). This preliminary study shows that 50-mg maintenance dose of clopidogrel may be acceptable in Japanese patients undergoing coronary stenting.

Thermal conductivity of Ni3Ga-X ternary alloys was comprehensively surveyed for 16 kinds of ternary elements X. The direction of ridge in thermal conductivity contours in γ′ single phase field agrees with that of solubility lobe of γ′ phase in a ternary phase diagram. The ridge direction is determined by the sublattice occupation of a ternary element.

The polymer of paclitaxel-eluting stents (PES) plays an important role in controlling the release of paclitaxel. Damage to the polymer of a PES that is used in a patient has not been demonstrated, although in-vitro studies report disruption of it. The present case report describes damage to a PES as delivery through a calcified coronary artery was being attempted.

Isotherms of the Ir-rich portion of the Ir–Al–X (X: Ti, Zr, Hf) systems are presented. In all of the isotherms three-phase equilibrium is found and no ternary compound is observed. Solid solubility of each phase is confirmed by chemical analysis by wavelength dispersive X-ray spectroscopy (WDS). The direction of the solubility lobe of L12–Ir3X with Al addition is explained in terms of the nearest neighbor interactions. Liquidus surfaces are also established by taking into account the microstructure of as-cast alloys, differential thermal analysis (DTA) data, Ir–X binary phase diagrams reported previously and the phase equilibria of the Ir–Al binary system investigated in the present study.

In-situ observation of the formation and disappearance of the surface relief associated with the twinning during the order-disorder transitions among CuAu-I (L10), CuAu-II (PAP) and disordered fcc phases was conducted using Confocal Scanning Laser Microscopy equipped with a gold image furnace. The Retro effect was confirmed in poly-crystal samples, however no evidence was found in single-crystal samples. Also observed in poly-crystal samples are that the disordering temperature detected by the disappearing of relieves is different from grain to grain, and that grain boundary cracking alleviates the Retro effect. The observed phenomena were explained based on the crystallographic orientation relationship among grains investigated by FESEM/EBSD in terms of the elastic strain effect around grain boundaries induced by transition. It was confirmed that in each grain the surface relieves correspond to a set of two {011} planes having a axis perpendicular to both planes in common. It was also found that the larger the average strain of two neighboring grains is, the lower the transition temperature. This observation was explained by the stress effect on the stability of a phase.

The authors have reported in the previous study that the sluggish decomposition of Nb3Si phase is effectively accelerated by Zr addition [1]. This is obvious at lower temperature range than the nose temperature of the TTT curve. In the present study a eutectic alloy containing 1.5 % of Zr was investigated. The crystallographic orientation relationships among phases, such as eutectic Nb and product phases formed by eutectoid decomposition of Nb3Si (eutectoid Nb and Nb5Si3phases) in the Zr-containing sample which was heat treated at 1300°C were investigated by FESEM/EBSD for further understanding of the decomposition process in alloy with a different microstructure.

Carcinoid tumor is commonly found in the rectum, stomach and duodenum, and rarely in the colon. Here a case of carcinoid of the ascending colon is described. A 60-year-old woman was admitted to the hospital for further examination of positive fecal occult blood. Barium enema and colonofiberscopy revealed a polypoid lesion in the ascending colon. Biopsy showed Borrmann type 2 carcinoid tumor. Right hemicolectomy wascarried out and a 1.8×1.6cm tumor in the ascending colon was confirmed. Postoperative course was uneventful and thepatient was dischargted on 3rd week after the operation. The patient is doing well eighteen months after the surgery. Forty-four cases seen in the Japanese literature were analyzed. Carcinoids of the colon were commonly in an advanced stage and the therapeutic results were poor. However, 22 cases without metastasis were able to have goodresults and long-term survival can be expected, if the tumor is in a relatively earlystage.