Broken Mechanism of Straight Copper Wires near Terminal due to Lightning High Impulse Current

When a lightning current flows through a copper wire, the copper wire would be broken at the terminal affected by electro-magnetic force. A straight thin copper wire such as 0.1mmΦ is melted due to the specific melting Joule integral: (j2t)m in an adiabatic condition. However, in these experiments it has been recognized that the thicker copper wires of 1mmΦ are not completely melted, but sheared mainly at the connecting terminal by a relatively low impulse current. Therefore, electromagnetic mechanical shearing stress, etc. are discussed adding to the ordinary Joule heating. New broken mechanisms were presumed and proved in additional experiments.【査読有

Continuous debris flow monitoring using DFLP and LVP on Sakura-jima Island

Since 2010, numerous debris flows have occurred on Sakura-jima Island due to rainfall events that occurred after extensive ash deposition associated with volcanic activity. The study area included the Nojiri and Arimura rivers in the southwestern and southeastern parts of Sakura-jima, respectively. Debris flow monitoring systems consisting of loadcell and pressure sensor (DFLP) were installed to evaluate characteristics of moving weight and so on during debris flows. The systems were installed at the Arimura River No. 3 sabo dam in June in 2012 and at the Nojiri River No. 1 sabo dam in 2014. In addition, LVP (Load, Vibration and Pressure) sensors consisting of loadcells and accelerometers for measuring vibration and pressure were installed on the riverbed for debris flow detection. Modified LVP systems were installed at the Nojiri River No. 7 sabo dam in February in 2015, and at the Arimura River No. 3 sabo dam in October in 2016. Interesting characteristics of debris flows were obtained by the DFLP and LVP systems. The findings showed that the sediment concentrations of both the coarse and the suspended and liquid phases could be estimated by the DFLP systems, and several patterns of debris flows were observed by the LVP systems

Photoinduced hydrogen release from hydrogen boride sheets

Hydrogen boride nanosheets (HB sheets) are facilely synthesized via ion-exchange treatment on magnesium diboride (MgB2) in an acetonitrile solution. Optical absorption and fluorescence spectra of HB sheets indicate that their bandgap energy is 2.8 eV. According to first-principles calculations, optical absorption seen at 2.8 eV is assigned to the electron transition between the sigma-bonding states of B and H orbitals. In addition, density functional theory (DFT) calculations suggest the other allowed transition from the s-bonding state of B and H orbitals to the antibonding state with the gap of 3.8 eV. Significant gaseous H-2 release is found to occur only under photoirradiation, which causes the electron transition from the s-bonding state to the antibonding state even under mild ambient conditions. The amount of H-2 released from the irradiated HB sheets is estimated to be 8 wt%, indicating that the sheets have a high H-2-storage capacity compared with previously reported metal H-2-storage materials

Potential Neuroprotective Effects of an LSD1 Inhibitor in Retinal Ganglion Cells via p38 MAPK Activity

Citation: Tsutsumi T, Iwao K, Hayashi H, et al. Potential neuroprotective effects of an LSD1 inhibitor in retinal ganglion cells via p38 MAPK activity. Invest Ophthalmol Vis Sci. 2016;57:6461-6473. DOI:10.1167/ iovs.16-19494 PURPOSE. The epigenetic mechanisms associated with ocular neurodegenerative diseases remain unclear. The present study aimed to determine the role of lysine-specific demethylase 1 (LSD1), which represses transcription by removing the methyl group from methylated lysine 4 of histone H3, in retinal ganglion cell (RGC) survival, and to investigate the details of the neuroprotective mechanism of tranylcypromine, a major LSD1 inhibitor. METHODS. The authors evaluated whether tranylcypromine contributes to neuronal survival following stress-induced damage using primary cultured rat RGCs and in vivo N-methyl-Daspartate (NMDA)-induced excitotoxicity. Additionally, the molecules associated with tranylcypromine treatment were assessed by microarray and immunoblot analysis. RESULTS. Tranylcypromine significantly suppressed neuronal cell death following glutamate neurotoxicity and oxidative stress. Microarray and immunoblot analyses revealed that p38 mitogen-activated protein kinase (MAPK)c was a key molecule involved in the neuroprotective mechanisms induced by tranylcypromine because the significant suppression of p38 MAPKc by glutamate was reversed by tranylcypromine. Moreover, although pharmacologic inhibition of the phosphorylation of the total p38 MAPKs interfered with neuroprotective effects of tranylcypromine, the specific inhibition of p38 MAPKa and p38 MAPKb did not influence RGC survival. This suggests that the non-p38 MAPKa/b isoforms have important roles in neuronal survival by tranylcypromine. Additionally, the intravitreal administration of tranylcypromine significantly saved RGC numbers in an in vivo glaucoma model employing NMDA-induced excitotoxicity. CONCLUSIONS. These findings indicate that tranylcypromine-induced transcriptional and epigenetic regulation modulated RGC survival via the promotion of p38 MAPKc activity. Therefore, pharmacologic treatments that suppress LSD1 activity may be a novel therapeutic strategy that can be used to treat neurodegenerative diseases

Sarcomere length-dependent Ca2+ activation in skinned rabbit psoas muscle fibers: coordinated regulation of thin filament cooperative activation and passive force

In skeletal muscle, active force production varies as a function of sarcomere length (SL). It has been considered that this SL dependence results simply from a change in the overlap length between the thick and thin filaments. The purpose of this study was to provide a systematic understanding of the SL-dependent increase in Ca2+ sensitivity in skeletal muscle, by investigating how thin filament “on–off” switching and passive force are involved in the regulation. Rabbit psoas muscles were skinned, and active force measurements were taken at various Ca2+ concentrations with single fibers, in the short (2.0 and 2.4 μm) and long (2.4 and 2.8 μm) SL ranges. Despite the same magnitude of SL elongation, the SL-dependent increase in Ca2+ sensitivity was more pronounced in the long SL range. MgADP (3 mM) increased the rate of rise of active force and attenuated SL-dependent Ca2+ activation in both SL ranges. Conversely, inorganic phosphate (Pi, 20 mM) decreased the rate of rise of active force and enhanced SL-dependent Ca2+ activation in both SL ranges. Our analyses revealed that, in the absence and presence of MgADP or Pi, the magnitude of SL-dependent Ca2+ activation was (1) inversely correlated with the rate of rise of active force, and (2) in proportion to passive force. These findings suggest that the SL dependence of active force in skeletal muscle is regulated via thin filament “on–off” switching and titin (connectin)-based interfilament lattice spacing modulation in a coordinated fashion, in addition to the regulation via the filament overlap

Ownership structure, investment behaviour and firm performance in Japanese manufacturing industries

Abstract Using data spanning the 1996-98 fiscal years of 247 of Japan's largest manufacturers, we empirically evaluate the extent to which a firm's investment behaviour and financial performance are influenced by its ownership structure. To do so, we examine six distinct categories of Japanese shareholders: foreign investors, investment funds, pension funds, banks and insurance companies, affiliated companies and insiders. Our findings strongly indicate that the relationship between the equity stakes of a particular category of investor and a firm's financial performance and investment behaviour is considerably more complex than is depicted in simple principal-agent representations. Such a result emphasizes the importance of making finely grained and contextually relevant distinctions when modelling and evaluating corporate governance relations

Seismic exploration at Fuji volcano with active sources : The outline of the experiment and the arrival time data

Fuji volcano (altitude 3,776m) is the largest basaltic stratovolcano in Japan. In late August and early September 2003, seismic exploration was conducted around Fuji volcano by the detonation of 500 kg charges of dynamite to investigate the seismic structure of that area. Seismographs with an eigenfrequency of 2 Hz were used for observation, positioned along a WSW-ENE line passing through the summit of the mountain. A total of 469 seismic stations were installed at intervals of 250-500 m. The data were stored in memory on-site using data loggers. The sampling interval was 4 ms. Charges were detonated at 5 points, one at each end of the observation line and 3 along its length. The first arrival times and the later-phase arrival times at each station for each detonation were recorded as data. P-wave velocities in the surface layer were estimated from the travel time curves near the explosion points, with results of 2.5 km/s obtained for the vicinity of Fuji volcano and 4.0 km5/s elsewhere

Stiffness model of machine tool supports using contact stiffness

The stiffness of machine tool supports should be properly designed for reducing both the ground disturbance vibration and the drive disturbance vibration. However, the stiffness cannot be easily calculated from the geometry and material properties of the support. In this paper, a 3D stiffness model of a machine tool support is proposed using contact stiffness. The stiffness in each direction is assumed to be determined by the contact stiffness at the interfaces and the bulk stiffnesses of the supports and the floor. The contact stiffness model proposed by Shimizu et al. is expanded to determine the contact stiffness in the normal and tangential directions of an interface. In the proposed model, the contact stiffness is obtained by multiplying the unit contact stiffness by the real contact area. The contact stiffness of concrete is experimentally investigated to estimate the stiffness between machine tool supports and the floor, and it was observed to be the primary determinant of the stiffness of interfaces between metal and concrete. Moreover, the unit contact stiffness of concrete is discovered to be less than 1/10 of those of the metals that were used for the study. The natural frequency and vibration mode shape of a model machine tool bed are also experimentally measured and used to verify the proposed stiffness model. The comparison of the results obtained from the two procedures shows that the natural frequency and vibration mode shape of a machine tool bed can be predicted using the proposed stiffness model