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The long-term durability of high-performance ceramics-coated glass should be appropriately evaluated prior to their practical applications. Fatigue properties of such materials should be clarified to ensure the long-term durability. In this work, a borosilicate glass was coated with alumina or silicon carbide thin films by sputtering method. Fatigue tests of coated glass were conducted under three-point bending. It was clarified that the fatigue life was elongated by coating ceramic thin films on glass and the fatigue life distribution in glass coated with thicker films shifted toward longer life region. Proof testing was carried out for coated glass specimens to remove specimens having lower fatigue lives. It was suggested that proof testing for fatigue of ceramics-coated glass was effective as a screening procedure which can remove weaker specimens by static pre-loading before fatigue tests. In correlating average fatigue lives, fatigue resistance strength was introduced as the average bending strength divided by the applied maximum stress. It was revealed that the average fatigue lives of every coated glass, including average lives after proof testing, were well correlated by a power function of the fatigue resistance strength and its modified parameter, irrespective of film material and thickness and also applied stress level.

The long-term durability of ceramics coated glass with high performance should be appropriately evaluated prior to their applications. Fatigue properties of such materials should be clarified to ensure the long-term durability. In this work, a borosilicate glass was coated with single- and two-layered ceramic thin films by a sputtering method. Fatigue tests of coated glass were conducted under bending mode, and fatigue properties of coated glass were investigated. It was revealed that the fatigue life of glass coated with two-layered film became longer compared with those of glass substrate and glass coated single-layered film. Hardness as surface characteristics of coated films, and bending strength as bulk property of coated glass were correlated with the average fatigue life, though no good correlation was found between them. Fatigue resistance strength was proposed as another strength parameter. It was found that the average fatigue life was adequately expressed by a power function of fatigue resistance strength.

We have investigated the water balance and mass balance for four years in Maekawa River basin on the eastern slope of Mt. Norikura-dake. In this region, the precipitation frequency is high from the rainy season to the autumn. The maximum base-flow discharge occurs in the spring snowmelt season. The pH and electric conductivity of the river water decline rapidly with the beginning of the snowmelt runo and temporarily decrease when the discharge increases temporarily in the rainy season or during a typhoon event. The Cl concentration of the river water increases in the early stage of snowmelt season since there is a considerable amount of sea salt in the snow. In addition, the NO concentration of the river water increases when the rainfall increases the discharge. The major ion concentration of the river water, except Cl and NO almost synchronizes with the change in the electric conductivity. In the mass balance of cations, the runo rate from the river basin considerably exceeds the atmospheric deposition rate to the river basin. This is because there is extremely much elution of ions from new volcanic rocks and soils. Further, the atmospheric deposition rate of NO is larger bigger with the biological consumption in the river basin than the runo rate from the basin.

Spatial variability of the chemical constituents of winter precipitation on the eastern-western slopes of Mt. Norikura (alt. 3025m) of Japan Northern Alps was examined to clarify the transport process of aerosol that flows over the mountain barrier. The concentrations of chemical constituents in the snow recorded at the upper part of the mountain (above alt. 2420m) make a little difference. However, at the lower part of the mountain (below alt. 2420m), Cl- concentration in the snow on the eastern slope was lower than that on the western slope; non-sea-salt SO42- (nssSO42-), NO3-, nssCa2+, nssMg2+ and NH4+ concentrations on the eastern slope was higher than that on the western slope. The prevailing westerlies raged at the western and alpine parts of the mountain. On the eastern part of the mountain, the easterlies were predominant. We infer that the snow below an altitude of 2420m, in comparison to the other parts of mountain, is under relatively greater influence of the local emission of the chemical constituents.

We conducted a snow survey in February 2006 and January 2007 in Japan Alps. Approximately 0.60m and 1.05m snowfalls were deposited at the study site in February 2006 and January 2007, respectively. It was observed that the occurrence of snowfall was due to the low pressure formation in the vicinity of Japan and it also being the winter monsoon period. As a result of the analyzed snowpack, including new snow at a high resolution every 0.03m, a plurality of high-electric conductivity layers were observed at di erent depths. From the measurement of the major ion concentrations, it was observed that the high-electric conductivity layers had di erent chemical characteristics. High concentrations of NO3 and SO42 deposits were observed in the snowpack layer that was formed due to the low-pressure system that passed in the vicinity of Japan. On the other hand, the layer that formed during the winter monsoon pattern, large amounts of sea salts were deposited in the snowpack in January 2007. However, layers with a high sea-salt concentration were not observed in February 2006. We analyzed the movement of the air mass that flowed into the study area. Air mass passed through the city at the time of the passage of the low-pressure system. In addition, the air mass that crossed the Sea of Japan entered the study area during the winter monsoon pattern. However, the movement of the air mass was di erent during the winter monsoon pattern in February 2006 and January 2007.

A snow pit study was conducted on Mt. Norikura in the Northern Japan Alps from January to April to clarify the chemical dynamics in the snowpack during the snowmelt season. Little snowmelt occurred before February , the first snowmelt occurred between February and , and the peak of the snowmelt season occurred after March . Snow layers with remarkably high Cl , NO , and SO concentrations in the snowpack were traced; furthermore, the snow layers with high SO concentrations were found to disappear first. It was concluded that the ease with which the ions were flushed out from the snowpack was SO NO Cl.

In this work, a borosilicate glass was coated with ceramic thin films by sputtering method. Roughness, hardness and static bending strength were measured as static characteristics of coated glass. Fatigue tests of coated glass were conducted under three-point bending. Although a large scatter was observed in fatigue life distributions, it was clarified that the fatigue strength was improved by coating ceramic thin films on glass. Specimens having lower lives in fatigue life distribution were adequately removed by proof testing. Therefore, it was suggested that proof testing for fatigue was effective as a screening procedure.

Sublethal ischemia leads to increased tolerance against subsequent prolonged cerebral ischemia in vivo. In the present study, we investigated the roles of the astrocytic glutamate (Glu) transporter GLT-1 in preconditioning (PC)-induced neuronal ischemic tolerance in cortical neuron/astrocyte co-cultures. Ischemia in vitro was simulated by subjecting cultures to both oxygen and glucose deprivation (OGD). A sublethal OGD (PC) increased the survival rate of neurons significantly when cultures were exposed to a lethal OGD 24 h later. The extracellular concentration of Glu increased significantly during PC, and treatment with an inhibitor of N-methyl-D-actetate (NMDA) receptors significantly reversed the PC-induced ischemic tolerance of neurons, suggesting that the increase in extracellular concentration of Glu during PC was critical to the development of PC-induced neuronal ischemic tolerance via the activation of NMDA receptors. Treatment with a GLT-1 blocker during PC suppressed this increase in Glu significantly, and antagonized the PC-induced neuronal ischemic tolerance. This study suggested that the reversed operation of GLT-1 was crucial to the development of neuronal ischemic tolerance.

Glutamate (Glu) is a major excitatory neurotransmitter of the mammalian central nervous system and under normal conditions plays an important role in information processing in the brain. Therefore, extracellular Glu is subject to strong homeostasis. Astrocytes in the brain have been considered to be mainly responsible for the clearance of extracellular Glu. In this study, using mixed neuron/astrocyte cultures, we investigated whether astrocytic Glu transporter GLT-1 is crucial to the survival of neurons under various conditions. Treatment of the mixed cultures with a low concentration of Glu did not produce significant death of neurons. However, cotreatment with dihydrokainate (DHK), a specific blocker of GLT-1, resulted in significant neuronal death that was suppressed by an antagonist of N-methyl-D-aspartate (NMDA) receptors. These results suggested that astrocytic GLT-1 participated in the clearance of extracellular Glu and protected neurons from NMDA receptor-mediated toxicity. When the cultures were treated with ouabain, an inhibitor of Na+/K+-ATPase, a low concentration of Glu resulted in massive neuronal death that was also suppressed by cotreatment with an antagonist of NMDA receptors. In this case, however, cotreatment with DHK significantly protected neurons from death, suggesting that GLT-1 was responsible for the death of neurons. The present study provides evidence suggesting that astrocytes use their Glu transporter GLT-1 to protect neurons from Glu toxicity, but, ironically, also use GLT-1 to kill neurons through Glu toxicity depending on their status.