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Life-history polymorphism in habitat use has been widely reported in aquatic migratory animals. Adult loggerhead sea turtles Caretta caretta in the North Pacific exhibit foraging-habitat polymorphism, showing a 2.4-fold greater reproductive output for neritic foragers than for oceanic ones. However, knowledge of how turtles in each habitat behave and what effect this has on reproduction remains limited. We combined horizontal movement and dive behavior analyses to explore foraging behavior and habitat utilization in adult female loggerheads in the North Pacific. Between 2016 and 2018, satellite relay data loggers were attached to 10 females nesting in Japan. The turtles were tracked for 219.2 ± 185.0 d (±SD) within the range of 10 to 521 d. Three foraging destinations were revealed, with different foraging tactics in each habitat: (1) the neritic East China Sea (ECS), (2) neritic coastal areas of mainland Japan (CMJ), and (3) oceanic North Pacific Ocean (NPO). ECS females mainly foraged on benthic prey with foraging-site fidelity; however, some turtles alternately preyed on benthos and plankton along with their seasonal migration. CMJ females also foraged on benthic prey with site fidelity, whereas NPO females foraged on plankton by drifting eastward with the oceanic currents. Dive-type analyses revealed that the proportion of time spent presumably foraging was similar among the 3 habitats, suggesting that the nutrient richness of prey items and the migration distance between foraging and breeding grounds may cause differences in reproductive outputs among different life-history types of loggerhead turtles.

Most of the nonhalogen compound show the less flammable behavior and low toxic gas emission comparing with halogen flame retardant compounds. In wire and cable industry have attracted considerable interest over the last 10 years to use nonhalogen flame retardant materials because of not only their known ecolabel regulation on electronic appliances in Europe but also regulation on telephone cable, optical fiber cables, electric power cable and other wire and cable applications in Japan. Nonhalogen flame retardant systems for wire and cable materials are now applied the next flame retardants to satisfy the regulations. The properties such as mechanical properties, electrical properties can be also obtained as the good balance for wire and cable applications. m-Mg(OH)2 with silicon compound will be able to consider to create non combustible inorganic barrier and restrict the heat transfer to prevent flame propagation.

The dry micro-blasting effects on the fracture resistance of PVD-AlTiN coated cemented carbide cutting tools were studied. The AlTiN coatings with the composition of (Al0.60Ti0.40)N were deposited using cathodic arc evaporation method. The two types of coatings, which had a compressive residual stress of 0.1 GPa (Low-σ) and 2.6 GPa (High-σ), were prepared. The coated samples were subjected to the dry micro-blasting treatment by Al2O3 grains at pressures of 0.11 MPa, 0.14 MPa, and 0.17 MPa. A milling test using AISI 4140 (42CrMo4) steel as the workpiece material was carried out for evaluating the fracture resistance of the prepared samples. The tool life cutting distance of Low-σ sample micro-blasted at 0.14 MPa and 0.17 MPa was 2.9 m and 7.2 m, respectively, largely extended as compared to that of as-deposited Low-σ sample, 1.0 m. On the other hand, the tool life of High-σ sample micro-blasted at 0.14 MPa was 8.6 m, almost same with that of as-deposited High-σ one, 8.8 m. Those results indicate that the dry micro-blasting effect on the fracture resistance is larger for the Low-σ coating than for the High-σ one.

Emerging requirements for inter-office/inter-datacenter short reach links for data center interconnects (DCI) and metro transport networks have led to various inter-office and inter-datacenter optical interface technologies. These technologies are bringing significant changes to systems and network architectures. In this paper, we present a system and ZR optical interface technologies for DCI and metro transport networks, then introduce the latest challenges facing the system framework. There are two trends in reach extension; one is to use Ethernet and the other is to use digital coherent technologies. The first approach achieves reach extension while using as many existing Ethernet components as possible. It offers low costs as reuses the cost-effective components created for the large Ethernet market. The second approach adopts low-cost and low power coherent DSPs that implement the minimal set long haul transmission functions. This paper introduces an architecture that integrates both trends. The architecture satisfies both datacom and telecom needs with a common control and management interface and automated configuration.

This study identified ventilatory and behavioural responses in the marbled sole Pseudopleuronectes yokohamae under experimentally induced progressive decreases in dissolved oxygen (DO) levels. Ventilation frequency showed an increase with decreasing DO levels from normoxia to 2·75 mg O

We have developed a 4-channel multi-anode MCP-PMT, SL10, which exhibits a performance of sigma_TTS ~ 30 ps for single photons with G ~ 10^6 and QE=20% under a magnetic field of B, 14 pages, 14 figures

A composite right-/left-handed stub resonator is presented as a cost-effective approach to designing low phase-noise oscillators. By engineering the dispersion of the CRLH stub line, the novel resonator exhibits unloaded-Q value beyond the limit of microstrip line resonators. A 9-GHz oscillator using the compact resonator achieved a phase-noise of −134 dBc/Hz at 1-MHz offset despite the high dielectric loss of the substrate used. The proposed resonator has potential of eliminating the need to use expensive materials or large-scale circuit to improve the oscillator performance.

A high density of vacancy clusters was observed in an impact compressed Ti–20Mo specimen to 100% strain. Age-hardening behavior of the specimen at 623 K for 28.8 ks was compared with that of as-quenched specimen. The highest hardness value of both specimens appeared at the aging time of 28.8 ks. The increment of hardness value of the impact compressed specimen due to aging was one-third of that of the as-quenched specimen. At that time, the size of aged ω-particles in the impact compressed specimen were smaller, however, the particle density was higher compared with those in the as-quenched specimen. These results suggest that vacancy clusters introduced by the impact compression become nucleation-sites of aged ω-particles, and a dominant age-hardening mechanism is considered as the pass-through mechanism. Aging behavior of hydrostatically pressurized Ti–15Mo–5Zr specimens at 623 K was investigated, and the maximum hardness value was lower than that of an as-grown Ti–15Mo–5Zr specimen. The results on size and density of aged ω-particles in the hydrostatically pressurized Ti–15Mo–5Zr specimens also suggests that the dominant age-hardening mechanism may be the pass-through one.

Oxidized copper layers prepared in hydrogen peroxide for chemical mechanical polishing (CMP) have been characterized using spectroscopic ellipsometry. In the spectral analysis of the oxidized copper layers, Lorentz oscillator model is used. Lorentz model was assumed a graded layer based on glow discharge spectroscopy analysis, the precise optical constants and thickness of oxidized copper layers was determined. Its optical constants and FT-IR analysis indicate that the oxidized copper layers consist of CuO and voids. The proportion of void was increases with growth of the oxidized layers. These analyses are useful to investigate an advanced CMP process using organic acid.

A 10-Gb/s burst-mode optical packet receiver module was fabricated. Its sensitivity was -24.8 dBm. Its sensitivity penalty due to packet-arrival timing jitter was less than 1.5 dB in arbitrary relative phase, and its total sensitivity penalty due to power fluctuation and packet-arrival timing jitter was less than 2.9 dB when the magnitude of packet-by-packet power fluctuation was 9 dB. We experimentally confirmed that our burst-mode optical packet receiver did not cause a penalty for wavelength division multiplexed (WDM) optical switching using the wavelength channel selector module.

In this study, we aimed to develop a new X-ray and gamma-ray monitor using the CdZnTe semiconductor detector, which has high sensitivity at room temperature. The pulse height spectra and the detection efficiencies of 10 mm/spl times/10 mm by 2 mm thick CdZnTe detector were measured in the energy range of 10 keV to 1.8 MeV by using monoenergetic X-ray and gamma-ray sources. The measured results showed very good agreement with the results calculated using the EGS4 Monte Carlo code taking into account the charge collection efficiency in the detector. By using two CZT detectors of 10 mm/spl times/10 mm/spl times/2 mm and 3 mm /spl times/3 mm/spl times/2 mm coupled with a filter, the weighted sum of a few energy channels with different cutoff energies was finally found to realize a flat energy response with an equivalent dose (counts per /spl mu/Sv) within /spl plusmn/30% or /spl plusmn/10% deviation.

During heating of nickel acetate solution at a constant rate of 4°C/min up to 350°C, α-type anion-exchangeable layered hydroxide Ni2(OH)3(OCOCH3)1.4H2O, containing the acetate anions in the interlayer spaces, first crystallized at 160°C. A second-stage intermediate phase losing the acetate guest in every second layer appeared at 180°C and subsequently transformed at 210°C to slightly disordered β-Ni(OH)2 phase with a small amount of acetate anions. β-Ni(OH)2 phases were gradually losing the acetate guest with increasing temperature, and perfectly ordered hexagonal-shaped β-Ni(OH)2 crystals with a mean diameter of 10 μm were obtained at 320°C. Above 340°C, dehydration of β-Ni(OH)2 to NiO occurred.

Recently, the energy responses of widely utilized seraiconductor X-ray detectors employed in many plasma-confmement devices were found to show contradictory behavior against the predietion from the conventional X-ray-energy-response theory in textbooks employed over the last quarter of the century for the analyses of plasma electron tem-peratures T e. This problem gave serious confusion for plasma researchers, who were utilizing X-ray data from semiconductor detectors including widely utilized X-ray-tomography data. For solving this problem, we proposed a new theory on the X-ray-energy response using X-ray-produced three-dimensionally diffusing charges from a field-free-substrate region in a detector. This novel theory is verified by the detailed data on a semiconductor X-ray response using synchrotron radiation. On the basis of these significant new findings, a novel method for X-ray diagnostics is proposed for the pur-pose of developing novel Te measurements. The physics principle is essentiall...

Anion exchangeable layered mixed basic salt (LMBA) Ni1−xZn2x(OH)2(OCOCH3)2xnH2O thin film was deposited onto a glass slide substrate through the hydrothermal decomposition of mixed aqueous solution of zinc and nickel acetates. The molar ratio of Zn/Ni in mixed solution affected the orientation of LMBA crystals on the substrate. LMBA thin films obtained at 130°C in Zn rich solutions showedc-axis orientation perpendicular to the substrate surface. The acetate ions of oriented LMBA thin film easily exchanged with most of the inorganic, as well as the organic, anions without destruction of the thin film.

Background. Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed. Methods. A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients. Results. Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal. Conclusions. Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon.

Since ω-phase crystals in β-Ti alloys formed by aging become nucleation sites of α-phase crystals due to further or high temperature aging, it is thought that this phenomenon can be utilized to produce stronger and more ductile (β+α) duplex Ti alloys. In order to form high density ω-phase crystals, the effects of a stress-aging and hydrostatic pressurizing on the formation of ω-phase crystals in Ti-20Mo and Ti-15Mo-5Zr alloys (mass%) were investigated using high resolution electron microscopy and dark field imaging methods. The results obtained are as follows: (1) An aging under a stress of a half of the yield stress promotes the precipitation of high density ω-phase crystals. (2) Hydrostatic pressurizing also promotes the formation of ω-phase crystals, and it is recognized that a hydrostatic pressure of 0.7 GPa initiates to form ω-phase crystals in a Ti-20Mo alloy.

Based on the two-dimensional analysis of energy and time-of-flight spectra, combined with the pulse-shape discrimination technique using a CsI(Tl) scintillation detector, a charged-particle spectrometer was developed to measure double-differential charged-particle emission cross sections with 14 MeV incident neutrons. Using this spectrometer, proton emission cross sections for Fe and α-particle emission cross sections for Be were measured to confirm the basic performance of the spectrometer. The measured data were compared with other experimental results, theoretical calculations and evaluations. Also, a model calculation based on kinematics for α-particle emission from Be was presented.

Donor pretreatment is a new concept in organ preservation. Pentoxifylline (PTX) has been reported to suppress the activation of Kupffer cells and to decrease injury to the hepatic graft after rat liver transplantation. We evaluated the efficiency of PTX pretreatment on the donor against hepatic injury following cold ischemia (CI) or warm ischemia (WI) using the rat liver transplantation model. Dose dependency: every rat was injected intraperitoneally with PTX (30, 50, or 80 mg/kg) or saline. One hour later, the portal vein (PV) and the hepatic artery (HA) were clamped for 30 min. Transplantation: the donor rat was injected intraperitoneally with 50 mg/kg PTX or saline, 1 hr before laparotomy. Animals were divided into two groups. In the CI group, grafts were preserved for 12 hr in University of Wisconsin solution at 4 degrees C and transplanted. In the WI group, the PV and the HA in the donor were clamped for 30 min before donor surgery, and the grafts were transplanted. Serum levels of tumor necrosis factor-alpha (TNF-alpha), glutathione S-transferase-alpha (GST-alpha), and aspartate transaminase (AST) were measured at 30 min, 3 hr, and 24 hr after reperfusion of the PV. Compared with those of a control group, the serum levels of TNF-alpha, GST-alpha, and AST in the PTX-pretreated groups were significantly lower after both CI and WI at 30 min and further suppressed in the WI group at 24 hr. These results indicate that PTX pretreatment on the donor is effective for suppression of hepatic injury after both CI and WI.

The translucent grease-like gel was obtained by heating the mixed solution of monohydrated barium hydroxide and titanium isopropoxide in ethylene glycol up to 145°C. The gel consisted of EG (ca. 90%) and residual flake-like microcrystals with a characteristic low-angle X-ray diffraction peak ( d =1.187 nm). The thermal decomposition of the gel proceeded through three major stages, viz., (i) evolution of EG (∼200°C), (ii) decomposition of EG moiety in microcrystal to form an amorphous carbonate (∼400°C), and (iii) crystallization of cubic BaTiO 3 with a grain size of 10 to 20 nm (∼600°C). Spectroscopic and thermoanalytical techniques were used to characterize the glycolate precursor and the intermediate isolated at various stages. Smooth and transparent BaTiO 3 films with 2–3 μm thickness were obtained by painting the gel once on several substrates and heating up to above 600°C. BaTiO 3 films prepared were strongly oriented along the (110) plane.

Electrical characteristics of epitaxial layers which are supplied by three manufacturers for molecular beam epitaxy (MBE) grown wafers and two manufacturers for metal organic chemical vapor deposition (MOCVD) grown wafers are analyzed. There are remarkable differences in the electrical characteristics between the MBE grown epitaxial-layers and the MOCVD grown ones. The heterojunction field effect transistors (HJFETs) fabricated by MBE show a large side-gating effect, while those fabricated by MOCVD have high threshold voltages for side-gating effect. The HJFETs fabricated by both methods have frequency dispersion in drain conductance ( G ds ). The activation energies of the associated deep levels are estimated at 0.34 eV for MBE and 0.73 eV for MOCVD. Diodes with n n layers, in which the growth is interrupted and the interface is air contaminated, show electron depletion and Fermi level pinning at the interface for the MBE wafers, while almost no peculiar effect at around the interface for the MOCVD wafers. Secondary ion-mass spectroscopy (SIMS) analysis indicate a large amount of oxygen and carbon contamination in the MBE wafers, while these impurities are under the detection limit in the MOCVD wafers. These results indicate that the interfaces formed by MBE contain deep levels of oxygen and shallow carbon acceptors, which cause G ds frequency dispersion and the side-gating effect, respectively. On the other hand, there is no substantial contamination in the MOCVD wafers, while G ds dispersion appearing in the MOCVD FETs can be attributed to the EL2 substrate deep level. These results indicate that there exist a large difference in the susceptibility to the surface cleaning between two technologies.

Recent developments in high speed silicon bipolar device technologies are reviewed. Bipolar device structures that include polysilicon are key technologies for improving circuit characteristics. Double polysilicon bipolar device structures, in particular, have made it possible both to form shallow junctions and to reduce device dimensions. Recent progress of silicon bipolar transistor technology using SiGe and the use of the SOI technology to obtain high speed operations are also reviewed. >

The accuracy of the three predominant techniques for measuring the surface temperatures of GaAs ICs under operation was investigated. The most important result is that the precision of commercially available computerized infrared microscopy is more limited than previously believed, especially in the case when the minimum IC element size is smaller than its spatial resolution. Some type of emissivity correction is necessary to obtain high precision. At this stage, therefore, the diode drop technique, an electrical method, and the transition point technique, a liquid crystal method, or their combination, must be used for measurement with high accuracy. The transition point technique has been determined to have a precision as great as +or-2 degrees C for measurement at the actual hot spot of non-sealed GaAs ICs. The diode drop technique is the only method which is useful for sealed ICs. >

A simple analysis method is proposed for output voltage waveforms and magnetic flux waveforms passing through the main stator parts of synchronous generators. The method considers the rotor movement in order to analyze the higher harmonic sequences and some techniques for simplifying the calculation using the symmetry of armature windings and stator slot arrangements. The effectiveness of the higher harmonics analysis method under saturated conditions, is verified by 50-MV A-class generator analysis. It is useful for quantitative evaluation of the voltage and magnetic flux waveforms and no-load saturation characteristics of synchronous generators. >

The hydrothermal treatment of Y2O3 in KF solution at 400°C gave single phase of yttrium hydroxide fluorides, Y(OH)3−xFx (0.65

Homoepitaxial growth on a porous silicon (PS) substrate anodized from Si(111) was investigated by reflection high energy electron diffraction (RHEED), high resolution scanning electron microscope (SEM) and Rutherford backscattering spectrometry (RBS). The Si growth was carried out on a PS substrate with various porosities (ϱp) at substrate temperatures of 760–820°C, resulting in that substrate temperatures above 800°C are desirable for an in-situ chemical etching of SiO2 by a Si beam. For ϱp 47%. These results are discussed in relation to the structure of the top PS surface. The effectiveness of the PS substrate anodized with dual rates (first at 5 mA/cm2 and secondly at 50 mA/cm2) is also discussed in comparison to the results for the single rate anodization.

The fracture strength of mechanically ground GaAs LSI chips was investigated in comparison to that of chemically thinned ones to confirm their appropriateness for practical use in the GaAs LSI manufacturing process. In addition, the effect of wafer-thinning on thermal resistance was evaluated quantitatively. GaAs LSI-sized 6.35-mm-square chips with mirror-ground back-surfaces (R/sub max/=0.1 mu m) have been confirmed to be almost as highly reliable as chemically thinned ones through fracture stress experiments. The 1 mu m post-grinding chemical etching in the original wafer-thinning technology proved to be effective for eliminating the surface flaws due to grinding, which act as stress concentrators and reduce mechanical strength. The thermal resistance of background 5-mm-square GaAs chips was observed to be expectedly low utilizing the newly established surface temperature measurement technology based on the diode drop technique. Furthermore, the thermal resistance was judged to be independent of the back-surface treatment. >

The authors investigate the reliability of mechanically ground chips through die-shear and thermal shock tests. The bonded chips, which were ground to 450 mu m thickness by an original technology, were proved to be as reliable as polished chips through 1000 cycles of thermal shock between -65 degrees C and +150 degrees C. No chip fracture occurred and no induced void was observed with scanning acoustic microscopy. The shear strength of the chips after thermal shocks remained at more than 10 kg, passing the MIL-STD-883C test. Surface flaws due to backgrinding, which would cause chip fracture, were eliminated by the slight chemical etching after backgrinding. Scrubbing action has been confirmed to be necessary to obtain void-free bondings consistently in low-cost production. The Sn in the Au-Sn preform easily forms on oxide film at the surface, which tends to prevent wetting at the bonding interface. This tin oxide film (300-400 AA) was observed through Auger electron spectroscopy (AES) to be broken down by scrubbing action. >

A novel GaAs MESFET structure with high radiation tolerance is proposed. Changes in electrical parameters of a GaAs MESFET as a function of total gamma -ray dose were found to be caused mainly by a decrease in the effective carrier concentration in an active layer. The structure was designed from a simulation based on an empirical relationship between the changes of the effective carrier concentration and the total gamma -ray dose. It was successfully demonstrated by utilizing a highly doped thin active layer (4*10/sup 18/ cm/sup -3/, 100 AA) grown by organometallic vapor-phase epitaxy (OMVPE). This MESFET can withstand a dose ten times higher (1*10/sup 9/ rads(GaAs)) than a conventional one can. >

A mass-production back-grinding technology that is applicable to a fully automatic wafer-thinning process in GaAs device manufacturing is described. Excellent productivity has been realized because the brittleness of GaAs has been overcome. A mirrorlike, stress-free surface was obtained by utilizing the wafer-rotating downfeed grinding method with slight chemical etching. The thickness of the deformed layer due to back-grinding was evaluated at 0.6 mu m. the wafer bow and the changes in electrical characteristics of GaAs devices caused by this layer were eliminated by chemical etching. The threshold voltages of GaAs MESFETs were confirmed to shift negatively by no more than 5 mV. This technology has been successfully demonstrated in several kinds of GaAs device fabrication processes. >

In order to develop a screen-printable polyimide paste, the structures, properties, and ratios of three major paste components (filler, binder, and solvent) were studied, and a film-forming strategy was established. This strategy comprises a novel type of polyimide particle filler, which can be dissolved in the binder and the solvent under the curing condition. A screen-printable polyimide paste was developed using this strategy. This paste gives uniform film with better mechanical properties than conventional polyimide paste, which comprises an insoluble polyimide particle filler. The effect of the solubility parameter of the solvent on mask swelling and moisture resistance was also examined. It was also examined. It was found that a lactone with a solubility parameter value of 18 approximately 20 (MJ/m/sup 3/)/sup 1/2/ is suitable as a paste solvent. The paste affords uniform pinhole-free polyimide films with good mechanical properties. As the mask swelling is low, the lifetime of stencil is longer than that of conventional pastes. >

Background Auxiliary partial orthotopic liver transplantation (APOLT) has recently been performed in patients with noncirrhotic metabolic liver diseases. However, long-term outcomes for the preserved native liver and the transplanted liver graft have not been clearly established yet. Methods The recipient was a 36-month-old girl with ornithine transcarbamylase deficiency. She underwent APOLT, using her father's left lateral segment. Results Liver function was normalized soon after APOLT and the patient was able to ingest a normal diet without medication. Coexistence of the well-functioning native liver and graft was demonstrated in a computed tomography scan, Doppler ultrasonography, scintigraphy, and histological examination, during a relatively long-term follow-up period. Conclusions APOLT seems to be most useful for the treatment of noncirrhotic metabolic liver diseases.

A manufacturable self-aligned LDD GaAs MESFET process called SRD has been developed. In this process, we controlled the fabrication conditions from lot to lot. Excellent control of the device characteristics not only across the wafer but also from wafer to wafer is obtained. The controllability of Vth is within /spl plusmn/50 mV. The standard deviation of Vth across the 3-in wafer is less than 30 mV for 0.5 /spl mu/m devices. In addition, other parameters such as g/sub m/, g/sub d/ are also well controlled within /spl plusmn/7% (Max-Min).

Recently the patient of the atherosclerotic disease associated with malignant disease has been increased. A 75-year-old man was referred to our section with an infrarenal abdominal aortic aneurysm (AAA) and a gastric cancer (GC). Preoperative coronary angiogram revealed the significant stenoses of the right coronary and the left anterior descending coronary artery. We selected the staged operation of off-pump coronary artery bypass grafting (CABG) [OPCAB] and the concomitant surgery for the AAA and the GC. Operative invasion could decrease with the surgical procedure of the OPCAB and the concomitant surgery compared to the conventional CABG or the separate operation. We used the aortic connector system during OPCAB to prevent such the serious complications of the aortic dissection or the systemic embolism due to the calcified ascending aorta.

We have developed a meander coil type linear sensor. When a detection coil is moved on a scale coil, mutual inductance fluctuates according to the displacement, causing the impedance change of detection coil. Therefore, displacement can be detected by using this impedance change. Impedance becomes like a sine wave form and impedance variation increases by resonating the coil, compared with the case when the coil is not resonating. When the width of the detection coil and scale coil are 0.5 and 0.6 mm respectively, impedance variation has its maximum of 38.6 /spl Omega/.

A 71-year-old man with congestive heart failure due to acute myocardial infarction was referred to our hospital. He was under the support of mechanical ventilation and the intraaortic balloon pumping (IABP) and coronary angiogram revealed the thromboembolism of the obtuse marginal artery. We completed the revascularization by the direct percutaneous coronary intervention. However, grade II mitral valve regurgitation and heart failure were worsening. Mitral valvuloplasty and the modified maze procedure through the partial lower sternotomy were performed. He is still in good condition 4 years later. Ischemic mitral valve regurgitation due to the coronary thromboembolism is very rare. Careful follow-up on the grade of ischemic mitral valve regurgitation is necessary even after the early coronary recanalization. The surgical approach of the partial sternotomy should be used in such a case of acute mitral valve regurgitation.

The aim of this study was to evaluate the operative techniques of total arch replacement, the clinical results and the survival curves of patients following this procedure.Since December 2001, 92 patients have undergone surgical treatment for aortic dissection and aneurysm. The total aortic arch replacement was performed in 24 of these patients. There were 16 men and 8 women, and the age range was 42 to 81 years with a mean age of 59.4 years. As the operative technique for total arch replacement, we used the 4-branched prosthetic graft, selective cerebral perfusion (SCP), continuous cold blood cardioplegia (CCBC), and open distal anastomosis under circulatory arrest. The combined operations were coronary bypass grafting in 4 patients, aortic valve suspension in 1 patient and a Bentairs procedure in 1 patient. Eleven (73.3%) patients with acute dissection required emergency operation.The hospital mortality rate was 25% (6 of the 24 patients). The causes of death were multiple organ failure (MOF) due to renal and mesenteric ischemia in 3 patients, cerebral infarction in 2 patients, myonephropathic metabolic syndrome (MNMS) in 1 patient, respectively. The data concerning extracorporeal circulation was 204+/-53 min in total pump time, 136+/-43 min in aortic cross clamp time, 83+/-14 min in SCP time and 48+/-10 min in circulatory arrest time, respectively. The long-term result in actuarial survival rate was 76% for 5 years.We consider the technique of total arch replacement using 4-branched prosthetic graft, SCP, CCBC, and open distal anastomosis is a useful operative method in patients with aortic aneurysm.

1000 kV UHV transmission lines in Japan pass through high mountainous areas, and are exposed to severe weather condition such as strong wind and heavy icing on conductors. In recent years, galloping phenomenon, which is one of the abnormal and lasting conductor oscillation caused by conductor icing and heavy wind, was observed in some UHV transmission lines. The authors, therefore, have developed anti-galloping devices applicable to UHV transmission lines, and conducted field tests using Takaishiyama test line to verify their effectiveness. The devices developed were based on eccentric weights plus rotation-free spacer type, which has successful past records for deterring galloping in many lines of multi-bundle conductors in service, and loose spacer type. As a result, it was verified that the developed anti-galloping devices could reduce conductor tension change considerably compared to the case without any countermeasure.

A copper-polyimide multilayer sunbstrate developed for high-density and high-speed application was confirmed to have a great advantage for high power-dissipating GaAs LSI chips through thermal resistance evaluation. 5-mm-square GaAs specimens and the authors' original chip surface temperature measurement technology based on the diode drop method were utilized to examine the thermal resistance. In spite of the low thermal conductivity of the polyimide, thermal vias formed in the substrate were most effective in keeping the surface temperature of LSI low. The expectedly low junction-to-case thermal resistance of 4.8 degrees C/W was obtained for the substrate having 2.6% thermal vias in the die-attach area. Face down bonded specimens by flip chip interconnect technology, which is the most suitable assembly technique for high-speed multichip modules, were also investigated. Consequently, thermal vias combined with thermal bumps were clearly proved to have a sufficiently positive influence upon decreasing the thermal resistance. >

The brittle damage layer of background GaAs LSI chips has been investigated through fracture toughness experiments, etching rate measurements, and SEM (scanning electron microscope) observations. The rough grinding damage which has a negative influence on the mechanical reliability of GaAs LSI chips penetrates to a 5-/spl mu/m depth on the finished surface. This is a little larger than than expected because the ductile damage layer due to rough grinding is only 0.6 /spl mu/m thick. However, this damage can be completely removed by 5-/spl mu/m mirror grinding and 1-/spl mu/m chemical etching, because the mirror grinding damage generates a 0.6-/spl mu/m-thick ductile deformation layer and a negligibly thin brittle deformation layer, which do not influence mechanical reliability. >