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An-88-year-old right-handed female complained of repeated intermittent hemiballism in the right upper and lower extremities. She presented to our hospital with monoparesis and asterixis of the right arm, but not hemiballism. Brain MRI revealed acute disseminated cerebral infarctions in the middle cerebral artery watershed area of the left hemisphere, including the striatum and cortical areas. Occlusion of the left internal carotid artery was also detected. She was diagnosed as acute cerebral infarction and received intravenous infusion, after which her neurological symptoms gradually improved. We presumed that the intermittent hemiballism was related to dysfunction of the motor loop induced by circulatory insufficiency in the left striatum, and that unilateral asterixis might be induced by hemodynamic hypoperfusion in the left frontal lobe. The hemodynamic changes induced by occlusion of the left internal carotid artery might be associated with pathogenesis of these involuntary movements.

Objectives: Amyotrophic lateral sclerosis (ALS) patients may present with cognitive and behavioral abnormalities similar to frontotemporal dementia (FTD). In this multicenter study we examined Japanese ALS patients with and without FTD in order to characterize the full extent of cognitive and behavioral abnormalities, including associations with functional motor status, anxiety and depression. Methods: Patients were evaluated using the Montreal Cognitive Assessment (MoCA), Frontal Assessment Battery (FAB), Hospital Anxiety and Depression Scale, ALS Functional Rating Scale-Revised, spirometry, and verbal fluency tests. Caregivers were asked to complete the ALS-FTD-Questionnaire (ALS-FTD-Q), a behavioral screen. We defined severe cognitive impairment (MoCA < 21 or FAB < 11), mild impairment (11 ≤ MoCA ≤ 25 or 11 ≤ FAB ≤ 15), and normal cognition (MoCA > 25 or FAB > 15). Severe and mild behavioral impairments and normal behavior were defined by the ALS-FTD-Q scores. Results: In 145 ALS patients, better cognitive scores were correlated with earlier age at onset, whereas a worse behavioral score was associated with a longer disease duration and higher level of anxiety and depression. Around seventy percent of all ALS patients showed mild (40–45%) or severe cognitive impairment with cognitive impairment outnumbering behavioral impairment fivefold. Cognitive functions were more impaired in patients with age of onset over 65 years, while behavioral scores were not related to age. Conclusions: Considering the high prevalence of in particular cognitive impairment, and the diversity of impairments, the cognitive and behavioral aspects of Japanese ALS patients should be given more attention clinically.

SH3TC2, known as the causative gene of autosomal recessive demyelinating Charcot-Marie-Tooth type 4C (CMT4C), was also found linked to a mild mononeuropathy of the median nerve with an autosomal dominant inheritance pattern. Using DNA microarray, Illumina MiSeq, and Ion proton, we carried out gene panel sequencing among 1483 Japanese CMT patients, containing 397 patients with demyelinating CMT. From seven patients with demyelinating CMT, we identified eight recessive variants in the SH3TC2 gene, consisting of five novel (pathogenic/likely pathogenic) and three reported variants. Additionally, from two patients with axonal CMT, we detected a reported recessive variant, p.Arg77Trp, which was herein reclassified as variant with unknown significance. Of the seven CMT4C patients (six females and one male), 2/7 patients developed symptoms at their first decade, and 5/7 patients lost their ambulation around age 50. Scoliosis was observed from more than half (4/7) of these patients, whereas hearing loss is the most common symptom of central nervous system (6/7). No median nerve mononeuropathy was recorded from their family members. We identified recessive variants in SH3TC2 from 1.76% of demyelinating CMT patients. An uncommon gender difference was recognized and the wild spectrum of these variants suggests mutational diversity of SH3TC2 in Japan.

Cowden syndrome is a rare autosomal dominant disorder characterized by multiple hamartomas of the ectoderm and brain. A 36-year-old Japanese man presented with right facial seizure during sleep and was admitted to our hospital. He showed cobblestoning over the tongue and palmar pitting but no neurological abnormalities while he was not having a seizure. Brain magnetic resonance imaging showed focal cortical dysplasia in the left frontal lobe. Electroencephalography showed sharp waves over the left frontal lesion. A genetic analysis revealed a novel mutation of PTEN. The administration of carbamazepine ended the seizures. This is the first Japanese case of Cowden syndrome with a novel PTEN gene mutation and cortical dysplasia.

Objective Melatonin is effective for treating patients with rapid eye movement sleep behavior disorder (RBD). Ramelteon, a novel hypnotic, acts as a melatonin receptor agonist. In the current study, we investigated the effects of ramelteon on sleep disorders, including RBD, in patients with Parkinson's disease (PD). Methods We evaluated 35 patients from multiple centers with idiopathic PD accompanied by sleep disturbances (age: 69.1±11.1 years; 17 men, 18 women; PD morbidity: 6.9±5.7 years; Hoehn & Yahr stage: 2.5±0.8; levodopa dose equivalent: 561±401 mg/day). The patients received 8 mg of ramelteon before sleep once daily for 12 weeks. Motor and sleep symptoms were evaluated both before and after ramelteon administration. Results Of the 35 patients enrolled in this study, 24 (68.6%) were diagnosed with probable RBD (pRBD) using the Japanese version of the RBD screening questionnaire. Ramelteon administration reduced the severity of sleep disturbances in patients with PD. It also lowered scores on the Japanese version of the RBD questionnaire in patients with PD and pRBD. Conclusion Ramelteon may have beneficial effects on sleep disturbances, especially on RBD in patients with PD.

Cowden syndrome is a rare autosomal dominant disorder characterized by multiple hamartomas of the ectoderm and brain. A 36-year-old Japanese man presented with right facial seizure during sleep and was admitted to our hospital. He showed cobblestoning over the tongue and palmar pitting but no neurological abnormalities while he was not having a seizure. Brain magnetic resonance imaging showed focal cortical dysplasia in the left frontal lobe. Electroencephalography showed sharp waves over the left frontal lesion. A genetic analysis revealed a novel mutation of PTEN. The administration of carbamazepine ended the seizures. This is the first Japanese case of Cowden syndrome with a novel PTEN gene mutation and cortical dysplasia.

Background Progressive supranuclear palsy (PSP) is a neurodegenerative disorder that is sometimes confused with Parkinson's disease, multiple system atrophy, and other disorders. The typical clinical features are categorized as Richardson's syndrome (RS), but other clinical subtypes include PSP-parkinsonism (PSP-P) and PSP-pure akinesia with gait freezing (PSP-PAGF). In this study, we determined the prevalence of PSP in a Japanese rural area compared to our previous 1999 report. Methods We collected data in Yonago City from 2009 to 2014 using a service-based study of PSP. We collected case history data from PSP patients in the area from our hospital. The crude prevalence and 95% confidence interval (CI) were calculated using the population demographics on the prevalence day of 1 October 2010. Age- and sex-adjusted prevalence was calculated by direct standardization to the population demographics in Yonago City on the prevalence day of 1 April 1999. Material and Results We identified 25 patients: 16 with probable RS, 4 with possible RS, 3 with clinical PSP-P, and 2 with clinical PSP-PAGF. The prevalence per 100,000 was 17.90 (male = 18.05; female = 17.76). The prevalence of PSP in Yonago in 2010 increased compared to the measurements from 1999. Conclusion The prevalence of PSP in Japan increased from 1999 to 2010.

It is generally believed that cortical spreading depression (CSD) demonstrated by Leao underlie migraine aura and migraine headache depends on the activation of the trigeminovascular pain pathway proposed by Moskowitz. The onset of migraine attack and the association between CSD and the trigeminovascular pain pathway have remained largely unknown. Recent animal studies indicate that CSD can activate trigeminal nociception and thus trigger headache mechanism. Meanwhile, the nature and mechanism of migraine without aura is still an open question. It is considered that the pain in migraineur is affected by hereditary factors, internal factors such as female sex hormone, and external factors as medication, meal, weather, stress, etc. We review here the current understanding of the migraine pathophysiology, focusing on recent advance regarding cortical spreading depression and pain.

Superconducting cable is expected to be one of the most economical ways to improve both the stability and capacity of electrical transmission and distribution lines, so several studies of high-temperature superconducting (HTS) cable have been initiated around the world. SEI was recently engaged by the Korea Electric Power Corporation (KEPCO) to install a 22.9 kV–1250 A HTS cable system, comprising a 100 m HTS cable, two terminations and a cooling system, all manufactured in Japan and shipped to the KEPCO Gochang test site in Cheolabuk-Do, ROK (Republic of Korea). After system installation and assembly, the cable was cooled with liquid nitrogen. Following several checks, including measurements of critical current and heat loss, and AC voltage and current tests, a commissioning test saw the cable carry 1250 A at 22.9 kV for 48 h, meeting all requirements. This report outlines the KEPCO HTS cable project, including system design, manufacture, installation and testing.

Albany HTS cable project is going on with the support of US Federal and New York States. The HTS cables included the Bi2223 tapes sintered by CT-OP (controlled over-pressure) process has 34.5 kV and 800 A capacity. The cable system was manufactured in Japan, and shipped to Albany. A 320 m cable and a 30 m cable were installed into the conduits under the ground. Subsequently, a splice box was assembled in the vault, and two terminations were connected to the HTS cable on the ground. Cryogenic refrigeration system was also mounted at the site by BOC. Initial cooling process was conducted as measuring distributed temperatures along the cable. The results of off-grid test, i.e. measuring heat loss, pressure loss, critical current, and DC withstand test, were carried out successfully. HTS cable system was connected to the real grid on 20 July 2006. The cable has been operated stably for 3 months as monitored by Remote Operation Center of BOC. This report outlines the installation and test results on Albany HTS cable project.

The Albany project has installed a high temperature superconducting (HTS) cable with a 350 m length in 34.5 kV and 800 Arms in the real power grid of the National Grid Power Company. The type of the cable is a 3 cores in a cryostat. Bi-2223 wires manufactured with SEI new sintering method, CT-OP, is used as both superconducting conductor and shield. The Cable was manufactured and shipped to the Albany test site after passing various tests such as Ic measurement, voltage tests, pressurized tests, and so on. Cable installations into a 320 m long conduits and a 30 m long conduit under ground was completed successfully. The cable was pulled with 2.5 ton tension, which is within its allowable limit. A joint between the 320 m cable and the 30 m cable was assembled in an underground vault. Cable terminations were also assembled at both ends of the cable. After all of the installation, the initial cooling was conducted successfully and then in-grid operation was started on July 20th in 2006 after confirmation of cable performance.

High temperature superconducting (HTS) cable is anticipated to transmit a large amount of electricity with a compact size and can reduce the transmission loss and greenhouse gas emission. The Albany project is being undertaken to verify the practicability of a long HTS cable in the real grid by performing a long-term operation test. The cable is 350-meter long and carries 800 A at 34.5 kV between two electric power substations (Menands and Riverside) in Albany, N.Y. [1]. The project is scheduled to run from 2002 to 2007 and is proceeding as planned. The HTS cable and its apparatus were manufactured in Japan, and the cable was shipped to the USA in the middle of August. After it arrives at the site, the cable installation and the apparatus assembly will be carried out sequentially. This system is expected to begin operating early next year after initial cooling. This paper gives an overview and the current status of the development of the HTS cable system.

The Albany Project plans to install a 350 m High Temperature Superconducting (HTS) cable in the power grid of the Niagara Mohawk Power Company to carry 800 Arms at 34.5 kV. The type of the cable has 3 HTS cores in one cryostat with Bi-2223 used for HTS conductor and shield layers. The three cores are housed within double SUS corrugated pipes which provides thermal insulation. The tapes are manufactured with a new innovative sintering method with controlled over pressure (CT-OP) technology. Polypropylene laminated paper (PPLP) is used as electrical insulation. The cable will be installed in long underground conduit. A cable joint will be made in an underground vault to connect a 30 m length of the cable with the remaining 320 m. The original Bi-2223 30 m cable will be replaced with a 30 m YBCO cable after long-term operation. The terminations at both ends of the cable will have three bushings in a cryogenic vessel. Typical performance evaluation experiments, such as cable bending tests, voltage tests, and fault current tests, have been conducted with sample cables to check the design. Voltage tests for 69 kV AC and 200 kV impulse were successfully applied to a 5 m cable in accordance with the Association of Edison Illuminating Companies (AEIC) code of 35 kV class cable. The cable will be manufactured and installed in 2004 and 2005, then, long-term operation will be started.

The relationship between mechanical properties and microstructure, especially volume ratio of Pearlite and Bainite, has been investigated. Using three type of specimens which have experienced different heat-treatment, tensile properties and fracture toughness (KIC)have been evaluated. The tensile strength and elongation of 50% Bainite mixed structure showed the mean characteristics of Pearlite and Bainite, while its 0.2 proof stress showed similar value of Pearlite. The result of COD test showed that the charactristics of mixed structure is closer to 100% Pearlite, which is due to the plastic deformation of Pearlite at the edge of crack. Such difference of fracture mechanism is considered to cause the above results described.

The low-alloy cast steels, which have the same chemical composition show three types of microstructures, i. e. bainitic structure (material SNA), pearlitic structure (material SNB) and mixed structure (material SNC) by changing heat treatment conditions. The authors have been investigated by the rotating bending fatigue tests and have been observed on the specimen's surface for fatigue crack initiation by the successive-taken replica method and fracture surface with SEM. The main experimental results are shown as follows ; (1) The fatigue limits of SNA, SNB, SNC and SNCs were 430, 225, 270 and 300 MPa, respectively. (2) The fatigue cracks of all specimens initiate at the blow holes, SNB, SNC, SNCs and SNA showed aspect of ductile fracture and brittle fracture on fracture surface. (3) The fatigue limit of experimental data becomes higher than that of the estimated values by Murakami et al's eq.

Purpose Rapid eye movement (REM) sleep behaviour disorder (RBD) is an important indicator of underlying synucleinopathies. However, the frequency of RBD in tauopathies such as progressive supranuclear palsy (PSP) remains unclear. In this study, we compared RBD-related symptoms and polysomnographic (PSG) findings between patients with PSP and those with Parkinson’s disease (PD). Methods We conducted clinical interviews of 20 patients with PSP, 93 patients with PD and their caregivers regarding RBD-related symptoms, and conducted PSG recordings on all the subject patients. We then compared the clinical backgrounds, PSG parameters, and frequency of RBD-related symptoms between the two groups. Results PSP patients had more severe symptoms of Parkinsonism and cognitive impairment, and took lower doses of dopaminergic agents compared with PD patients. The PSP group had lower values for both estimated total sleep time and sleep efficiency on PSG compared with the PD group ( p = 0.002, p = 0.021, respectively). The PSP group also included a significantly smaller number of patients having REM sleep without atonia (RWA) compared with the PD group ( n = 5, 20.0% vs. n = 56, 60.2%, p = 0.003). None of the PSP patients were experiencing RBD-related symptoms at the time of the investigation, while 30 PD patients (32.3%) had RBD-related symptoms. Discussion The existence of RWA as well as RBD-related symptoms was less frequent in patients with PSP versus patients with PD. Differences in brain stem pathology and/or disease course between the two disorders might influence this difference.

The teratogenicity of combined exposure to noise and cadmium was studied in mice. ICR mice were exposed to a wide octave-band of noise at 100 dB(C) for 6 h on d 7 of pregnancy in one of two ways: continuous exposure or intermittent (15 min on/15 min off). Cadmium sulfate at 1 or 2 mg/kg was intraperitoneally injected on d 7 of pregnancy. Four groups were exposed to both cadmium and noise. On d 18 of pregnancy, fetuses were examined for external and skeletal malformations. Another experiment was performed with two other patterns of noise exposure: continuous exposure for 3 h, and intermittent exposure (5 min on/5 min off) for 6 h on d 7 of pregnancy. In the groups exposed to continuous noise for 6 h, total percentages of malformed fetuses were significantly higher than that in the control group, but there were no significant increases of total percentages of fetal malformations in the combined treatment groups in comparison with the groups given the same dose of cadmium alone. The percentages of skeletally malformed fetuses in groups exposed to 6 h of continuous noise were significantly higher than in groups that received saline or the same dose of cadmium. There were no significant differences in the total percentages of malformed fetuses between the control group and the groups exposed to a total of 3 h of noise, whether continuously or intermittently. Although combined treatment with cadmium and noise resulted in an increase of total percentages of malformed fetuses compared to the same dose of cadmium alone, the interactions between cadmium and noise showed no synergistic effect on teratogenicity. The magnitude of teratogenicity due to noise is much weaker than that of cadmium, and is therefore easily masked by that of cadmium in statistical tests of the significance of differences.

The purpose of this study is to evaluate the prosthodontic usefulness of laser doppler flowmetric (LDF) measurement of the blood flows in gingival and palatal mucosae and skins overlying the masseter muscle and temporomandibular joint.High reproducibility was obtained in the LDF measurement of the blood flows at these sites.The gingival mucosal blood flow (GBF) was increased by application of a cold or hot stimulus and decreased by clenching. It was also decreased by experimentally produced gingivitis. GBF was found to be correlated to the volume of gingival groove fluid which was measured simultaneously.The palatal mucosal blood flow (PBF) was increased transiently by application of a cold or hot stimulus and decreased by impression. It was also decreased by attachment of an experimental palatal plate.The skin blood flow over the masseter muscle (MBF) was increased by clenching. No significant change was observed in MBF by chewing of gum. The skin blood flow over the temporomandibular joint (TBF) underwent no change by irradiation of soft laser beam or application of a topical antiinflammatory agent. Both MBF and TBF were decreased by pulsing from a myomonitor.These results suggested that LDF is useful in the field of prosthodontics as a method for measurement of blood flows.

The present study was undertaken to elucidate subjective symptoms reported by some individuals exposed to various sounds, including infrasound. Narrow band infrasound of 5 Hz at center frequency and wide octave band audible noise were separately applied at an intensity of 95 dB. Parameters such as involuntary eye movement with the eyes visually fixed, body sway and pulse-wave were investigated. The total amount and power percentage in the low-frequency band of involuntary eye movement was significantly increased upon exposure to infrasound. Furthermore, confusion in postural control at the time of transition from opening to closing of the subject's eyes was inhibited by this exposure. Conversely, pulse-wave height decrement was observed upon exposure to both sounds, although this was smaller in the case of infrasound as compared with that of noise. These findings are taken to indicate that the effects taking place via the two different pathways were mixed in the subjective symptoms, and that functional changes caused by infrasound exposure were unrelated to an emotion stimulated by acoustical sensation.

A manufacturing process for dual-structured turbine disks made from PM nickel-base superalloys has been specially developed. The disks are composed of two metals: AF115, which has superior stress rupture properties, was used in the rim region, and TMP-3, which has good tensile properties and a low cycle-fatigue life, was used in the bore region. A 400mm diameter dual-property disk was successfully produced through double-stepped HIP treatment and superplastic forging, in which gas atomized powders composed of the above alloys were consolidated into a well-designed preformed structure. After heat treatment, the microstructure of the product was very fine and homogeneous in the bore region, and coarse grains were obtained in the rim region. The mechanical properties were of such high quality as to enable practical use as a turbine disk.

A method synthesizing Functionally Gragient Materials (FGM), in which the chemical composition gradually varies, was developed by employing Low Pressure Plasma Spraying (LPPS). Desirable FGM-coating, 30mm in the diameter and 1mm thick on a copper or stainless steel substrate was obtained by concurrently mixing ceramics powders and metal powders in plasma arc. The FGM coating made by this process was proved very resistive against thermal shock under a CO2 laser lighting and a large temperature difference test by a 30kW-Xe arc lamp.

Elevated temperature fatigue tests were conducted on P/M HIP'ed superalloy, MERL76. The defects, such as preciptitates on the prior particle boundaries (PPBs), gas-porosities and nonmentallic inclusions, were found at fatigue origins. The relation between defect size, ai, and fatigue life, Nf, was independent of defect types and was formulated asNf·Δσmeq=h·a1-m/2iΔσeq=Δσ√1+2Eg(n)/n+1·Δep/Δσwhere m: the exponent in crack propagation law, da/dN=CΔKm, h: a material constant, E: Young's modulus, g(n): a function of cyclic strain hardening exponent, n, and Δep: plastic strain range.The relation between threshold stress, Δσth, and defect size, ai, was also expressed asΔKth=2/π·Δσth√π(ai+a0)where ΔKth: threshold stress intensity factor for long cracks. The value, a0, was about 0.1mm, which coincided with the size estimated by an experimental relationship between grain size and a0 on steels.The usage of Ar-treated powders and the hot-work after HIP'ing improved fatigue life since they prevented PPB failure. Furthermore, the usage of fine powders is preferable because it can reduce the size of pores and inclusions.

The cross-linking structure of the ultra violet (UV)-cured resin prepared from dipentaerithritol hexacrylate (DPHA) was characterized by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) combined with supercritical methanolysis. The MALDI-mass spectrum of the decomposition products obtained by supercritical methanolysis contained a series of peaks of sodium-cationized methyl acrylate (MA) oligomers up to around m/z = 4000 formed through selective cleavage and methylation occurred at ester linkages in UV-cured DPHA. Furthermore, in order to observe widely distributed sequence lengths in the cross-linking junctions, the decomposed products of the cured resin were then fractionated using size exclusion chromatography followed by the MALDI-MS measurements of the individual fractions. The MALDI-mass spectra of the lower molar mass fractions mainly consisted of a series of peaks of MA oligomers around m/z values of several thousands, whereas those of higher molecular weight showed a broad peak up to m/z ca. 180000. The observed distributions of the supercritical methanolysis products suggested that the network junctions in the given UV-cured resin were composed of up to around 2000 acrylate units.

High-pressured water atomization is a viable production method for fine metal powders used for metal injection moulding and for additives in sintered parts. The atomization mechanism using two types of water jet nozzle (Cone and V-jet nozzle) under high pressure up to 70MPa was studied. The pulverizing capability under high-pressured water atomization strongly depends on a gas stream induced by the ejecting effect of water jets, which surround the melt stream. A mean particle diameter of less than 10 μm can be obtained by the V-jet nozzle.

The mechanical properties of powder Ni-base superalloy consolidated by HIP were obtained for AF 115, MERL76 and Mod. IN100, where the influence of powder handling atmosphere upon the low cycle fatigue life of the consolidated materials was investigated in order to establish the powder consolidation process. Moreover, the differences of mechanical properties between HIPed material and conventional casted one were examined. The results obtained are as follows :1) In order to get a confidence of low cycle fatigue life, the powders should be handled in the protected atmosphere such as Ar gas or vacuum.2) Powder consolidation process making use of HIP equipment was established and made it possible for the HIPed materials to possess the satisfactory mechanical properties.3) Low cycle fatigue life and tensile properties of HIPed materials are much superior to those of conventionally casted ones. This is due to the nature of homogeneity and fine crystal structure of powder materials.The stress rupture strength of the powder materials is, however, lower especially in the low stress region than that of casted one. This difference between them may be due to the crystal grain size.

Atomized powders of MERL76 superalloy were rolled at room temperature and their recrystallization behaviour in the atomized and rolled powders was examined at various temperatures. Further, the superplastic behavior of IN100 superalloy powder compact, consolidated by hot isostatic pressing was examined at 1050°C and in the range of strain rates from 4×10-5 sec-1 to 8×10-3 sec-1. The recrystallized grain size of rolled powder particle was finer than that of the atomized powders. Fine grained materials of full density were obtained at the HIP conditions of 1100°C, 90 MPa and 1 hr using both atomized and rolled IN100 powders. These HIP'ed materials showed a superplasticity and the maximum elongation of these from the rolled powder compact was 110%. This value was slightly lower than that of the materials made from the fine powder compact. The cold rolling was effective for grain refining of coarse powders, but it should be operated in a protective atmosphere to prevent the occurrence of PPB (Prior Particle Boundary).

A new derivatizing reagent, pentafluorobenzyl methanesulphonate, has been synthesized and used to determine inorganic anions by gas chromatography. Bromide, iodide, cyanide, thiocyanate, nitrite and sulph iodide, cyanide, thiocyanate, nitrite and sulphide in water at mM levels could be simultaneously pentafluorobenzylated in dichloromethane, using tetra-n-amylammonium chloride as a phase-transfer catalyst. The resulting derivtives were subsequently determined by gas chromatography with flame ionization detection. In water at μM levels, except for cyanide and nitrate, the anions could also be derivatized to their pentafluorobenzyl derivatives in the biphasic reaction system and be detected by gas chromatography with electron-capture detection. In addition to the biphasic reaction method, bromide, iodide and thiocyanate were simultaneously pentafluorobenzylated in an homogen in an homogeneous reaction system of aqueous acetone or aqueous methanol, without the use of a phase-transfer catalyst.

Low-pressure plasma spray (LPPS) has been recognized as a superior surface modification technology due to the improved coating properties. In the field of steel-making equipment, hard materials, high temperatures, erosion and corrosion resistant materials are greatly needed. In this paper, an application of Cr 3 C 2 −NiCr coating by LPPS is mainly discussed. It is observed from X-ray diffraction analysis that the material composition changes very little between prepared powder and coating by LPPS. Application to guiding rollers in a hot strip mill has achieved a life-expectancy more than 10 times that of conventional materials.

The fatigue properties of P/M superalloys can be significantly damaged by defects, which act as sites for fatigue fracture initiation. These defects can be introduced as inclusions either during the melting operation, during powder atomization or during subsequent handling.Equipments for producing cleaner powders by Ar gas atomization have been designed and installed, and the properties of produced MERL76 superalloy powders were examined. As a result, this method was capable of producing fine and clean powders with an average grain size of 56 μm and an oxygen content of less than 100 ppm. Results also indicated that the amount of non-metallic inclusions of produced powders was less than those in the commercialized powders, which was detected by the new water elutriation method.

This study was undertaken in order to clarify the effects of infrasound on vestibular functions by comparing observations of eye movement under exposure to infrasound and audible noise. Twenty-five healthy males were exposed to a wide octave-band noise, (approx. 125 Hz to 4kHz) or to 16 Hz or 5 Hz at 95 dB for 3 minutes. Their involuntary eye movement with the eyes visually fixed in the horizontal direction was measured before and during exposure with their eyes open and closed. The extent of eye movement before the exposure was significantly greater with eyes closed than with eyes open. This difference was intensified by 5-Hz exposure, but exposure to the noise of 16-Hz infrasound had no effect. The power percentage in the low frequency-band, determined by spectral analysis of the eye movement, was significantly greater with eyes closed than with eyes open before the exposure. This increase in the power percentage in the low frequency-band was reinforced by the 16- and 5-Hz exposures, while no effect was observed upon exposure to the noise. These results suggest that the potential of the vestibulo-ocular reflex was increased upon exposure to infrasound, regardless of whether or not the subjects perceived any sensation.