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Changes in the activities of nitric oxide synthase (NOS) during embryonic development, and the distribution of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) isoforms were examined in unfertilized mouse oocytes at the second meiotic metaphase (MII) stage and in fertilized mouse embryos during preimplantation development. In addition, the effects of NOS inhibitors on mouse preimplantation development in vitro were investigated. The activities of NOS in MII oocytes and fertilized embryos during the preimplantation period were determined by NADPH-diaphorase staining. Although NOS activity was detected in unfertilized MII oocytes, the intensity of staining was much weaker than that of fertilized embryos at the one-cell stage. There was a decrease in NOS activity in embryos from the four-cell to the eight-cell stage; however, NOS activity increased again in embryos at the morula stage, particularly in the inner cell population. In the expanded blastocysts, staining was confined to the inner cell mass. Immuno-cytochemical staining showed that eNOS and iNOS were expressed in the cytoplasm of oocytes and embryos during the preimplantation period, and eNOS was also distributed in the nuclei of the embryos. When one-cell embryos were treated with 1 mmol N(omega)-nitro-L-arginine methyl ester (L-NAME) l(-1), their development in vitro was arrested at the two-cell stage. This inhibition of development was overcome by the addition of 1 mmol L-arginine l(-1) to the medium. These observations indicate that nitric oxide plays an important role as a diffusible regulator of cell proliferation and differentiation, especially at the developmental transition from the two-cell to the four-cell stage during preimplantation development of mice.

Background: Preoperative factors including age and body habitus affect intraoperative hypothermia during general anesthesia. We hypothesized that preoperative blood pressure also plays a contributory role in the induction of intraoperative hypothermia. Methods: We evaluated the effect of preoperative systolic blood pressure (SBP) on core temperature during lower abdominal surgery under general anesthesia. In 36 female patients under 65 years of age, patients with a preoperative SBP of 140 mmHg or greater upon arrival in the operating theater were assigned to the high SBP group (n=18), while those with SBP below 140 mmHg were assigned to the normal SBP group (n=18). Anesthesia was maintained with isoflurane and nitrous oxide combined with epidural buprenorphine, and routine thermal care was provided intraoperatively. Results: There were no significant differences in age, height or weight between the two groups. Tympanic membrane temperature in the normal SBP group started to decrease significantly from 15 min after induction of anesthesia compared to that in the high SBP group, and continued to decrease further at two hours after induction. Vasoconstriction threshold, determined to be tympanic membrane temperature at the time when a forearm minus finger skin surface gradient exceeded 0 °C, was significantly higher in the high SBP group than in the normal SBP group. Conclusion: These results suggest that preoperative SBP has some preventive effect on the decrease in intraoperative core temperature during lower abdominal surgery under general anesthesia.

NMR properties of 59Co and 31P in CoRhP with orthorhombic TiNiSi structure are reported. Field-swept NMR spectra of 59Co show very broad ones from nonmagnetic Co sites where satellite peaks due to quadrupole interaction are smeared out. The Fourier transformed spectrum of 31P NMR has two peaks. It is suggested that the Co and Rh atoms do not order but their sites are mixed. The mixing is consistent with a Rietvelt analysis of X-ray diffraction powder patterns where a mixing of 10% of Co atoms into Rh sites is estimated. This kind of mixing seems to be one of the origins of the variety of magnetic and electric properties of MRuP and MRhP (M=3d transition metal) systems. The nuclear spin-lattice relaxation rates of 59Co and 31P in CoRhP obey Korringa relations at high temperatures and they show stepwise decreases with decreasing temperature at 11 K where the static susceptibility has a peak. The behaviors are interpreted as an onset of a charge density wave (CDW) at 11 K rather than an onset of an antiferromagnetism.

We propose a new technique of nano size CDW formation by applying two types of accurately controlled ion-beams to one dimensional bulk conductor. The CDW sample has 400 A thickness and 1000 A width. As a result of our investigation, we have found that the nano-fabricated CDW shows collective sliding and negative resistance above some threshold electric field in low temperature region.

SummaryPercutaneous microwave coagulation therapy (PMCT) is a new therapeutic technique for the treatment of solid neoplasms. In this report, we present our 5 years' experience with PMCT for the treatment of 69 hepatocellular carcinomas (HCCs) in 60 patients. Under ultrasonic guidance, we inserted a 2.1 mm guiding needle percutaneously toward the lesion and a needle electrode was precisely positioned within the lesion. Microwaves, with a frequency of 2450 MHz, were produced for 60 s, with 60 W emission. The overall success rate was 72%, the mean disease-free period was 24.2 months. The procedures were safe and tolerable for all patients. Slight pain and heat sensation were encountered in most patients. We consider PMCT an effective and safe treatment for HCCs.

The current status of developing single-ion implantation (SII) which enables us to implant dopant ions one by one into fine semiconductor regions is summarized. Single-ions extracted from a focused ion beam (FIB) have been implanted into a nuclear track detector CR-39 and the average number of implanted ions by chopping the ion beam has been evaluated by counting the etch pits on the CR-39 formed by each single-ion incidence. The detection efficiency of the single-ion incidence into a target has also been evaluated by comparing the count of secondary electrons and the implanted ion number, and the controllability of implanted ion number by SII is discussed.

The dependence of single ion induced interface traps on the oxide electric field during irradiation has been investigated quantitatively by using single ion microprobe (SIMP) and single ion beam induced charge (SIBIC) imaging. The result shows that the number of interface traps induced by 2 MeV He ions increases with the dependence of the E 0.2 ox on the oxide electric field. The dependence of interface traps on the oxide field during ion irradiation has been found to be very similar to that of oxide trapped holes. The cause of the field dependence of interface traps has been discussed quantitatively.

Since 2010 at SPring-8, we have been demonstrating a seeded free-electron laser (FEL) in the extreme ultra violet (EUV) region by high-order harmonics (HH) generation from an external laser source in a prototype test accelerator (EUV-FEL) [1]. In FEL seeding as a full-coherent high-intensive light source for EUV user experiments, a high hit rate of successfully seeded FEL pulses is required. Precise measurements of the electron bunch charge distribution (BCD) and its arrival timing are crucial keys to maximize and keep three-dimensional (3D: spatial and temporal) overlapping between the HH pulse and the electron bunch.

We demonstrate the monolithic integration of MOSFETs with thermo-optic (TO) Mach-Zehnder switches on SOI platforms. Successful driving operation was achieved for the TO switch via MOSFETs, which is promising for realizing driver-on-chip large-scale circuit switches.

Soft-error immunity of a 256 kbit DRAM against quasi-heavy ion irradiation has been evaluated using He single ion microprobe at Waseda University. The technique for hitting micron size area with arbitrary number of He ions enables us to simulate the space environment under irradiation of heavy ions with higher LET than that of /spl alpha/-particles. From the maps of error-sensitive sites obtained by irradiating various number of-He ions, the threshold LET of soft-errors, effect of diffused charges on the soft-error cross section, and susceptibility to multi-bit errors have been estimated. The results of measuring single-ion induced noise charges at the PN junction which is considered as equivalent to the storage node of the DRAM have been presented and the origins which determine the soft-error immunity under irradiation with various LET have been discussed.

In the course of developing single ion implantation (SII) technology for control of doping in semiconductor fine structures and modification of surfaces/interfaces, both in an atomic scale, defect generation by single ions in the surface region of graphite has been investigated with scanning tunneling microscopy (STM). Argon ions with acceleration energy of 30 to 60 keV have been implanted into highly oriented graphite crystal. Craters have been formed at the ion incident sites. The feature of craters shows swelling from the undamaged surroundings. The volume of the swelling fluctuates among the craters, which reflects the fluctuation in the number of ion-induced defects near the surface. A good correlation between the amount of the surface defects and the projected range of each implanted ion has been confirmed by simulation of cascading. Consequently it has been found that the swelling volume of individual craters characterized by STM can be a good measure of the statistical distribution of each implanted ion and ion induced defect distribution.

Radiation effects induced by MeV He single ions in pMOSFETs and nMOSFETs in commercially available CMOS4007 have been studied extensively. The key results from this study are: (1) pMOSFETs are more fragile than nMOSFETs in terms of threshold voltage shift, (2) nMOSFETs are more susceptible than pMOSFETs to the degradation of subthreshold swing. The different features in the radiation effects have been discussed comprehensively.

We studied the effects of aging on alpha-receptor-mediated vasoconstrictive responses to sympathetic nerve activity in 16 healthy aged [75.8 +/- 2.7 (SE) yr] and young men (33.8 +/- 2.0 yr). Muscle sympathetic nerve activity (MSNA), heart rate, and blood pressure were analyzed during slow respiration (0.1 Hz). Peak amplitude and phase were calculated from a cosine function fitted with 0.1 Hz by using the least squares method. The latency of the pressor response to MSNA, defined as lag time from the peak of MSNA to diastolic blood pressure, was significantly longer in the aged than the young group (7.1 +/- 0.3 vs. 5.4 +/- 0.4 s; P < 0.01). The extent of pressor response to MSNA, defined as diastolic blood pressure rise in response to increase in total MSNA, was significantly lower in the aged than the young group (0.038 +/- 0.006 vs. 0.099 +/- 0.024 mmHg/unit, P < 0.001). These results suggest that alpha-receptor-mediated vasoconstrictive responses to MSNA may be attenuated in the elderly.

SUMMARY A study on effective use of rear braking force to improve a brake performance and vehicle dynamics are carried out. On a ordinary condition, the rear braking force could be more increased to a conventional braking force distribution. Based on this thought, the brake performances are estimated. The results show the effects not only improve the brake performance but also reduce a pitching at braking and moderate a vehicle OS behavior in a turn during braking. These are verified by experimental test vehicle equipped with a rear braking force control system.

The nitriding process is widely used to improve the tribological properties and wear resistance of metal surfaces. An “edge effect” occurs due to distortions of the electric field around the corners and edges of the components, although the components are well heated. This results in nonuniformity in properties such as the hardness and thickness of the surface layer. Recently, there has been considerable interest in active screen plasma nitriding (ASPN). In this process, the edge effect is completely eliminated because the plasma is produced on the cage and not directly on the samples, and sputtering of material from screen is important for ASPN. In this study, austenitic stainless steel AISI 316L and silicon (Si) were nitrided by ASPN to investigate the effect of surface deposits from the screen. ASPN experiments were carried out using a DC plasma-nitriding unit. The sample was placed on the sample stage in a floating potential and isolated from the cathodic screen and the anode. The screen, which was AISI 316L expanded metal with 38 % open area ratio, was mounted on the cathodic stage around the sample stage. ASPN was performed in 25 % N2 + 75 % H2 atmosphere for 7.2–90 ks at 673 K under 200 Pa. After nitriding, the nitrided samples were examined using scanning electron microscopy, X-ray diffraction, Vickers microhardness, and glow discharge optical emission spectroscopy. The nitrogen-expanded austenite (S phase) was formed on the surface of both samples. Additionally, γ′-Fe4N and CrN were also formed on the Si surface. The thickness of the surface deposited layer increased linearly with increasing nitriding time. That of the nitriding layer of S phase also increased, whereas the deviation from parabolic law was observed. This result suggested that the surface deposited layer suppressed the formation of a nitriding layer.

A novel technique which enables us to hit a micron-size device area with a single ion has been established. Evaluation of single event immunity at particular device sites has become possible using this technique. Latchup immunity of a CMOS IC has been evaluated by measuring ion-induced charges which trigger latchup. The amount of charges has been found to have a site dependence.

A vacuum‐compatible double‐crystal monochromator with constant exit‐beam height has been installed and operated for several years at beamline BL7A at the UVSOR facility at the Institute for Molecular Science, Okazaki, Japan, The beamline is used both for the photons from a normal bending‐magnet section and those from a 4 T superconducting three‐pole horizontal wiggler. Various pairs of monochromator crystals are being used with sufficient intensity and signal to noise ratio of the output signal. Basic structure of the beamline, the mechanism of the monochromator, and some typical spectra of materials with absorption edges between 850 eV and 4 keV are reported.

Photoemission spectra of the Al-Cu-Fe quasicrystal with the icosahedral phase were studied at room temperature. The line shape of the overall observed spectrum is like a large peak on a plateau cut-off at EF. The large peak observed at about 4 eV below EF seems to originate mainly from the 3d state of Cu atoms. The bump was observed at about 1 eV below EF. The high resolution experiment showed an anomalous valley at EF in the electronic density of states. This means that the dip at EF in the DOS has a half-width 0.3-0.4 eV and that its depth is 70% of the value for a no-dip case.

An erase and program control system has been implemented in a 60-ns 16-Mb flash EEPROM. The memory array is divided into 64 blocks, in each block, erase pulse application and erase-verify operation are employed individually. The erase and program sequence is controlled by an internal sequence controller composed of a synchronous circuit with an on-chip oscillator. A 60-ns access time has been achieved with a differential sensing scheme utilizing dummy cells. A cell size of 1.8 mu m*2.0 mu m and a chip size of 6.5 mm*18.4 mm were achieved using a simple stacked gate cell structure and 0.6- mu m CMOS process. >

We studied whether delivering postoperative analgesia, using a patient-controlled epidural analgesia (PCEA) device was effective and safe in elderly patients. We enrolled 40 patients aged65 years (elderly group) and 40 patients aged 20-64 years (young group) scheduled for elective major abdominal surgery. PCEA infusion was started following completion of surgery. Mean (SD) fentanyl consumption (10.7 (3.7) compared with 10.5 (2.7) microg.kg(-1), p = 0.76) and number of times patients pressed the bolus switch (32 (36) compared with 44 (38), p = 0.16) during the first 24 h postoperatively were similar in the two groups. Pain scores, which were similar in both groups at rest, were significantly lower in the elderly on coughing (at 24 h, p0.05). In addition, average pain scores were similar at the time of PCEA bolus demands in the two groups. Elderly and young adult patients therefore required similar amounts of patient-controlled epidural fentanyl to produce satisfactory pain relief.

Glutathione is a potent endogenous scavenger of oxygen free radicals in living cells. Decreased levels of glutathione are involved in aging and some neurodegenerative diseases. To investigate an effect of glutathione depletion in the horizontal cells of carp retina, the gap junctional intercellular communication between horizontal cells was studied using both techniques of intracellular recording of light-induced responses and dye coupling of the fluorescence, Lucifer Yellow (LY). The glutathione depletion was accomplished by single injection of 2.5μmol L-buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis. Intravitreal injection of BSO induced a dramatic reduction of retinal level of glutathione 2 days after treatment. The low level of glutathione continued for a further 4–5 days and thereafter was gradually recovered to about 70% of the control level by 50 days after injection. In normal retinas, the response amplitude of horizontal cells was monotonically enhanced as the diameter of the spot increased (0.5–4.0mm) and correspondingly the dye diffusion area was wide, as the injected LY normally diffused to several neighboring cells. Depletion of glutathione by BSO significantly altered the spatial properties of horizontal cells by increasing the response amplitude to central spots and slightly decreasing that to peripheral annuli, which were observed by 4 days after treatment. It also restricted intracellular LY to one or two cells. Accompanying the recovery of the cellular level of glutathione, the spatial properties and dye coupling of horizontal cells were recovered to normal. These alterations of spatial and dye coupling properties of horizontal cells were well correlated with accumulation of reactive oxygen species (H2O2) during glutathione depletion. The present data have demonstrated for the first time that neuronal gap junctional channels can be modified by intracellular glutathione via oxidative stress.

The application of SiC-based power electronics device to large capacity AC/DC converter is studied and its advantages are estimated quantitatively on operational loss of AC/DC converter. As the electrical characteristics of SiC crystallized material is excellent, SiC-based power electronics device has some attractive features of switching element for converter. Concerning operational loss reduction of AC/DC converter, lower on-state resistance of SiC-based power electronics device is the important parameter to decrease conduction loss. In the case of AC/DC converter system of ITER class power supplies, the operational loss of converter using SiC-based power electronics device is compared with that of conventional thyristor AC/DC converter.

In this paper, a new concept of pulse power supplies that can boost up the pulse current and/or can reduce the voltage rating of the power supplies is proposed. A magnetic energy recovery switch (MERS) consists of four MOSFETs or IGBTs and a capacitor. The MERS is connected in series to a power supply and a coil. The MERS is a switch module and it has no power supply in itself. When the current of coil decrease, the MERS absorbs the magnetic energy stored in the coil and re-generates a high voltage in the capacitor. When the current increases, the MERS adds the voltage to raise currents faster than the time constant of the coil. Because the MERS re-generates a voltage required for the inductance of the coil by using the previous magnetic energy. So, the power supply only has to supply a voltage required for the resistance of the coil. The MERS can reduce a voltage rating and capacity of the power supply. By using the MERS with a power supply of a pulsed magnet, high-repetition pulsed current can be realized with a comparatively small capacity of the power supply. Some applications require a controlled current waveform. By controlling the MERS using PWM, the controlled current waveform is obtained. Operation principles and characteristics of the MERS are described. Some experiments were carried out. Experimental results confirm that the MERS can reduce voltage ratings of power supplies and/or generate high-repetition pulsed boost-up currents

IEEE802.11 wireless LAN systems are being widely used and multiple wireless LAN coexistence systems like 802.11b/g are available at the same time. However, in such environments, network performance is likely to degrade because the CAMA/CA mechanism does not always work well. Especially in the 802.11b/g systems, issues on performance degradation caused by the CTS-protection mechanism come to surface. To manage and maintain the QoS in such environments, it is required to detect and estimate the QoS degradation effectively. We found that the so-called retry ratio (i.e., the retry ratio of the numbers of transmitted packets to retransmitted ones) is strongly correlated with IP-packet quality metrics through our IP packet experiments. It is thus considered that retry ratio is applicable to managing the quality of some applications over wireless LAN.

A 1Mb DRAM using a half Vcc biased memory cell with a reduced electric field of 2MV/cm will be reported. A shared sense amplifier design and a continous nibble mode are also included. Additionally, a test pin allows testing as a 256K×4 memory. Die is 65mm2.