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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.

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.

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.

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.

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.

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 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.

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 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.

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.

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.

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.

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.

Endometriosis is a state where ectopic endometrium occurs in the muscular layer of the uterus, ovary, Douglas' pouch, peritoneum, and colon. It is rare that ectopic site is the inguinal region. This paper describes a case of extrapelvic endometriosis occurring in the inguinal region. A 46-year-old woman was admitted to the hospital because of a right inguinal tumor with pain. The patient had noticed a right inguinal tumor in January 1980, which accompanied by a pain during menstrual periods and gradually enlarged. In December 1989, she was diagnosed as inguinal hernia by a nearby hospital and referred to the hospital. On admission blood laboratory test was normal. Body CT revealed a solid mass in the right inguinalregion. Excision of the mass was performed. The excised specimen was a grayish-white solid tumor, 4×3cm insize. Histologically, the specimen showed endometriosis. Postoperative course was uneventful, and there has been on local recurrence, as of 2 years after the surgery. Thirty-three cases seen in the Japanese literature are also reviewed here.

It is rare that Crohn's disease causes perforation. This paper describes a case of Crohn's disease causing ileal perforation. A 20-year-old man was admitted to the hospital because of abdominal pain. The abdomen was distended and muscle guarding and Blumberg sign were observed. Chest X-ray film revealed no free air under the diaphragm. White blood cell count was 10600, with neutrophilia. The patient was diagnosed as peritonitis and emergency operation was carried out. At laparotomy, perforation of the ileum associated diffuse peritonitis was observed. Partial ileal resection and drainage were performed. In the resected specimen cobblestone appearance and longitudinal ulcer were observed. Histologically, transmural inflammation with noncaseous granuloma was seen and Crohn's disease was confirmed. The patient was discharged on the 38th day after surgery. There has been no recurrence, as of 2 years after the operation, and the patient is followed on an ambulant basis. Two hundred-odd cases and 56 cases of perforated Crohn's disease have been reported in the world and Japan respectively so far. A review of the literature is also presented here.

It is noticed that the decreased peripheral leukocyte and platelet and activation of intravascular coagulation are induced by direct effect of endotoxin to the vascular system. But its mechanism is still uncertain.We used E-coli 0-26 endotoxin injected into the Donryu rats by intraperitoneal injection, 20mg per kg. and observed the vascular changes of lung, liver, kidney and adrenal, chronologically 30min. 1, 3 and 5hrs. by light and electron microscope. And we also studied the vascular permeability using fesin and horseradish peroxidase as tracers. By electron microscopic examination, we noted the increased pinocytotic vesicle, swelling of mitochondria, widening of intercellular spaces and vacuolization of endothelium and medial cells in the arterial system of lung, liver, adrenal and kidney. These findings were prominent in kidney in the early stage.And the destruction of polymorphonuclear leukocyte and platelet, deposition of fibrin were observed in sinusoids of the liver, in capillaries of the adrenal and kidney. And, especially, the kidney showed early prominent changes compared with other organs. The degenerative leukocytes were encountered strikingly in pulmonary vessels.According to the vascular clearance methods, the electron dense tracers and reaction products of peroxidase are also seen in the pinocytotic vesicles and cytosomes of the endothelium through the endothelial intercellular spaces. The extent of increased permeability depends upon the qualitative difference of properties of vesicles and the vesicular system in the endothelium, medial cell and other mesenchymal cells.The effects of the accumulation and disintegration of polymorphonuclear leukocytes and the break down of their lysosomes in blood vessels may a result of the direct cytotoxic effect of the endotoxin. The authors believe that the endotoxin installed shock may have resulted from the above mentioned vascular changes and the increased vascular permeability which is distinctly substantiated from the investigation of tracer methodology.We conclude that the activated coagulability, as the direct effect of endotoxin administration is a very important factor in accelerating the pathologic changes of the vessels.