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Using scanning tunneling microscopy (STM), we study the adsorption of copper-phthalocyanine (CuPc) on the anisotropic Au(110)-(1 × 2) surface as a function of coverage. For the initial adsorption at room temperature, we observe CuPc monomers as well as a molecular chain that forms along the step edge. By STM manipulation, we reveal that the CuPc adsorption is accompanied by surface reconstruction from the initial adsorption stage; the periodicity beneath the monomer and the chain changes locally from (1 × 2) to (1 × 1) and (1 × 3), respectively. This finding highlights that the Au atom mobility of the surface plays an essential role in CuPc adsorption. At higher coverage, we observe the development of CuPc chains along the [110] direction on the terrace with periodicities of (7 × 5) and (5 × 5), and compare the obtained results with those from the previous studies by diffraction methods.

The interaction of Ag atoms with graphene moiré on Rh(111) was studied by scanning tunneling microscopy. Upon adsorption at 15 K, the Ag atoms existed mainly as monomers at specific sites in the moiré unit cell because thermal diffusion was suppressed. The Ag atoms exhibited a dI/dV peak at ~0.5 V above the Fermi level, which was assigned to Ag(5s)-C(2p) anti-bonding state. At elevated temperature, the Ag adatoms were thermally activated to diffuse and form clusters, wherein the activation barrier depended on the moiré periodicity. Furthermore, migration was induced by injecting tunneling electrons into the anti-bonding state. This work provides atomic-scale insight into the aggregation process of metal adatoms on metal-supported graphene.

The structure and electronic states of copper phthalocyanine (CuPc) on Cu(100) and Cu(110) were studied mainly using scanning tunneling microscopy/spectroscopy (STM/STS). We observed that the molecule adsorbs flat on Cu(100), and the lowest unoccupied molecular orbital (LUMO, e) is shifted down to the Fermi level, which indicates a partially filled state. The inherent fourfold symmetry of the molecule remains intact upon adsorption, and thus, the degeneracy of LUMO is maintained on the surface. Conversely, the molecule adsorbs in a low-symmetry configuration on Cu(110) and preferentially forms a dimer. Thus, the degeneracy of LUMO is lifted, and the split LUMO is shifted below the Fermi level. We propose that the hybridization with surface d band plays an important role in the energy level alignment and its structure dependence for CuPc on Cu surfaces.

Li 2 TiO 3 ceramics have been irradiated with xenon (Xe) ions in the energy range of 18–160 MeV at ambient temperature. The effect of ion irradiation on the order in the atomic arrangement of Li 2 TiO 3 crystal was examined by X-ray diffraction (XRD) and Raman spectroscopy. The results show that the atomic arrangement in Li 2 TiO 3 is strongly disordered by the high energy Xe ion irradiation. The destruction of long-range order due to the irradiation was confirmed from the reductions in XRD intensities of the (0 0 2) supercell reflection. The destruction of short-range order was confirmed from the reductions in the Raman intensities and disappearances of Raman bands with fluence. The disordering is more efficient with the increase in the electronic stopping power than with fluence or accumulated electronic energy deposition. These disorders due to the irradiation are discussed in relation to irradiation parameters such as electronic stopping power, accumulated electronic energy deposition and fluence.

The irradiation behavior of Li 2 TiO 3 under a fusion reactor environment was simulated by simultaneous irradiation of Li 2 TiO 3 by the triple ion beams and the respective single ion beams of O 2+ , He + and H + . The microstructural changes in Li 2 TiO 3 caused by the irradiation were measured by Raman spectroscopy and FT-IR photoacoustic spectroscopy. The results suggest that the formation of TiO 2 due to displacements by irradiation occurs, and the irradiation defects generated by irradiation trap hydrogen and increase the amount of hydroxyl near the surface. Such phenomena are believed to significantly affect the chemical form of the released tritium and the tritium inventory in the breeding materials of a fusion reactor.

The disordering in the fused lithium metatitanate (Li 2 TiO 3 ) irradiated with high energy ions (160 MeV Xe, 80 MeV O) was examined by room-temperature X-ray diffraction and Raman spectroscopy. The exposure of Li 2 TiO 3 to Xe ions at fluences of 3.3 × 10 16 and 3.4 × 10 18 /m 2 was found to cause complete disordering in its surface layer, unlike the surface layer exposed to O ions up to maximum fluence of 1.4 × 10 20 /m 2 . An extent of disordering with irradiation is associated with the electronic stopping power of the incident ions in Li 2 TiO 3 rather than the fluence and accumulated radiation dose.

The synergistic effects of displacement damage and atomic hydrogen and helium on swelling of the ferritic/martensitic steel, F82H, has been investigated. The irradiation was performed at temperatures between 470 and 600 °C to 50 dpa (displacement per atoms) under conditions of simultaneous ion beams consisting of Fe3+, He+ and H+ ions or Fe3+ and He+ ions. The swelling of F82H steel under triple beams with 18 appm He/dpa and 70 appm H/dpa was larger than that under dual beams with 18 appm He/dpa. The swelling in F82H under triple beams increased with decreasing irradiation temperature from 0.1% to 3.2%, while swelling under dual beams was between 0.04% and 0.08%. On the other hand, in the case of triple beam irradiation with a high ratio of gas/dpa, the swelling tended to increase with irradiation temperature. The swelling in ferritic/martensitic steels is significantly enhanced by the synergistic effect of displacement damage, hydrogen and helium atoms.

Samples of polycrystalline ceramics of MgAl2O4 irradiated at the ambient temperature with 85 MeV I7+ iodine ions to doses up to 1×1019 m−2 is observed to be amorphized up to depths around 6 μm from the ion-incident surface for a dose of 1.2×1019 m−2, through a cross-sectional transmission electron microscopy. A step height of 1 μm is formed across the border between the masked and irradiated regions of the surface. The height of the step is observed to increase sharply from the irradiated area towards the edge at the border, forming a peak as tall as 1.5 μm. A glossy, silver-gray film with a thickness less than 0.1 μm is unexpectedly observed to have formed on the surface of samples of MgAl2O4 and MgO, in about 3.5 years aging after the irradiation to 1.2×1019 m−2, being left untouched in the air. The film is easily peeled off along grain boundaries and found to be amorphous from the electron diffraction pattern. The film from MgAl2O4 sample contains Al, Mg and Si. Silicon, which is one of impurities, is found to be enriched noticeably at the surface.

Samples of polycrstalline sintered ceramics of Al2O3, MgAl2O4 and MgO were irradiated at room temperature with 85 MeV I7+ ions to doses up to 1.2×1019 m2. Both MgAl2O4 and Al2O3 samples are observed to be amorphized up to depths of approximately 5–6 μm for a dose of 1.2×1019/m2, through a cross-sectional transmission electron microscopy (XTEM). No defected clusters are observed at approximately 7.5–8.5 μm, where displacement damage due to the nuclear energy deposition is predicted to peak at 1 dpa (displacement per atom). No amorphization is observed for the MgO sample irradiated with the same dose. Instead, X-ray diffractometry (XRD) revealed an enhancement of the diffraction peaks for the (200), and (400) reflections and a reduction of peak intensities from other reflections, as compared with those before irradiation. This indicates that an atomistic rearrangement may occur along an ion path to form a new surface with the lower energy.

現在,防除を要する水稲の主要病害は紋枯病を除いて,いもち病,ごま葉枯病,ばか苗病,もみ枯細菌病,苗立枯細菌病等種子伝染性病害が大部分を占める.これらの種子伝染性病害の根本的な防除を目的として無病種子の作成を試みた.通常種子として用いるもみでの種子伝染性病害病原菌の存在部位は主にもみ殻で,玄米はほぼ無病原菌であることから,玄米に保護膜として水溶性ポリアクリル樹脂と粉末活性炭で二重被膜した水稲の無病化種子“玄米種子”を開発した.本玄米種子を育苗箱で通常に育苗することにより育苗期の病害であるばか苗病,もみ枯細菌病,苗立枯細菌病,本田移植後ではいもち病が種子消毒剤による薬剤防除とほぼ同等に防除可能であることが明らかになった.本種子を用いることにより種子もみの長期間の種子浸漬や種子消毒の削除,種子消毒剤の廃液処理問題解消,本田期での種子伝染性病害防除作業の削減が可能となり,種子伝染性病害の根本的防除および,環境と人間に優しい農業確立に大きく貢献するものである.

Depth profiles of implanted H atoms were measured for single crystalline Al2O3 samples irradiated at 923 K with dual or triple beams of 0.25 MeV H-, 0.6 MeV He-, 2.4 MeV O-ions or 2.6 MeV Al-ions. The peaks occur at 1.55 and 1.45 μm in the depth profiles measured for the H + Al dual beam irradiation and H + O dual beam case, respectively. The ratio of the peak areas is over 4, which is much larger than the implanted H atom ratio of 1.1, indicating that implanted Al atoms suppress the mobility of H atoms. However, the ratio becomes almost 1 between the triple beam samples with H + He + O-ions and with H + He + Al-ions at comparable doses. The fact demonstrates that implanted He atoms overwhelm the effects of the implanted self-cation/anion excess atoms on the migration behaviors of implanted hydrogen and radiation produced point defects, with the resulting sluggish cavity growth observed.

A cross-sectional transmission electron microscopy (XTEM) technique utilized in examining the sintered alumina (Al2O3) sample irradiated by 85.0 MeV iodine ions I7+ to 2.8×10 18 m −2 reveals that almost complete amorphization takes place up to depths around 2 μm. Several grains including grains about to be fading out at depths of 2.5–3.5 μm are seen to have moved from the yet-amorphized region leaving the amorphized region behind. The amorphized regions extend up to depths around 4.5 μm for the sample irradiated to 12×10 18 m −2 . Any defect clusters cannot be observed in grains located at depths around 8 μm, where nuclear energy depositions are predicted to peak to about 1 dpa. The present results clearly demonstrate that the energy depositions through electronic process in alumina irradiated with heavy ions like present I7+ transform the crystalline phase into amorphous ones even near room temperatures, for accumulated electronic energy depositions above some 1.5–2 GGy with deposition rates above 4–5 keV/nm/ion.

The chief principle and properties of a novel noncascaded type optical bandpass filter with three unique general characteristics are presented. This device is based on a combination of a Michelson interferometer and a Gires-Tournois resonator (GTR). First, the filter has square-like frequency response with zero ripple, wide flat-top (0.74/spl times/bandwidth), unity contrast, sharp steepness, and infinite rejection ratio when GTR front surface mirror reflectance /spl rho/ is equal to one-third. Second, this filter possesses variable bandwidth and center wavelength tunability features with simple control mechanism and nanosecond temporal response potential. Third, the desired features of the filter can be synthesized easily by mere inspection since only three parameters are required, and their expressions are given in simple analytic forms. Numerical results showing these features are presented and other characteristics are briefly discussed.

Damage structures in a single crystal Al 2 O 3 sample irradiated at 923 K with simultaneous triple beams of H-, He-and O-ions with respective energies of 0.25, 0.9 and 4.7 MeV up to a fluence of 2.7, 3.5 and 5.5 x 10 20 m 2 , were examined by cross-section electron microscopy. High density dislocation loops are formed to a depth of 2.4 μm and the loop density increases with increasing depth. Cavities are observed in bands with the swelling peaked at depths of 1.4, 1.9 and 2.3 μm for H-, He- and O-ion implanted regions, respectively. The growth of cavities is most pronounced in the O-ion damaged region with a maximum size of 13 nm and a density of 2-3 x 10 23 m 3 . In a sample annealed for I h at 1273 K after the irradiation, cavities grown to an average size 40 and 60 nm with a maximum of 70 nm were observed in He- and O-ion implanted regions, respectively, and the density was decreased by about two orders.

We systematically observed the damage morphology along ion traces by transmission electron microscope in 230 MeV Au-irradiated ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{x}$ single crystals. The results gave us a basic understanding of how high-energy ions interact with the target atoms, lose their energy, and are stopped. Three types of transitive defect morphologies, large-angle-deflected columnar defects, cascade-defect-dotted columnar defects, and ordered cascade defects, were found to be located between two typical defect morphologies, parallel columnar defects and disordered cascade defects, in different penetration depth regions. The mechanisms for the formation of these transitive defect morphologies were suggested. The analysis of ion-energy deposition in each penetration depth region and the results obtained indicated that our suggested mechanisms are reasonable. This study also supplied us with an effective experimental method to directly estimate the columnar defect size distribution versus ion penetration depth and the ion-energy thresholds to produce columnar defects and cascade defects.

A cross-sectional electron microscopy technique was used to examine the microstructural evolution in single crystalline pure alumina (Al2O3) irradiated at 923 K with triple beams of 0.25 MeV H+, 2.4 MeV O2+ and 1.l MeV He+ to fluences of 6.3, 2.8 and 6.7 × 1020/m2. Irregularly shaped cavities are observed in two regions of depths of 0.2–1.8 and 2.2–2.5 μm. The cavity densities peaked at about 1.0 and 2.3 μm (7 × 1022/m3 and 4 × 1022/m3, respectively) with average sizes of 15 and 8 nm, respectively. The cavities formed in the He ion damaged region are aligned and mostly interconnected in the 〈0 0 0 1〉 direction to form irregularly shaped cavity tunnels. Tiny cavities, smaller than 5 nm, are formed inhomogeneously along irradiation-produced dislocations in the region 0.4–1.0 μm from the sample surface, where neither H nor O atoms are predicted to be stopped. This formation of cavities in the near-surface region is in marked contrast to that observed in the Al2O3 sample irradiated with simultaneous beams of 0.25 MeV H+ and 2.4 MeV O2+ ions to a fluence 2.5 times higher than that in the triple beam case. In the triple beam irradiation, cavities with comparable sizes are observed only near the end of ion ranges.

Damage structures in a single crystal α-Al2O3 sample irradiated with triple (0.25 MeV H+, 0.6 MeV He+ and 2.4 MeV O2+) ion beams at 923 K to a peak dose of 3.6 dpa were characterized by dislocation loops distributed from the region close to the incident surface to the region of 1.8 μm in depth, with cavities being formed in the restricted region of depths from 1.2 to 1.75 μm. A similar depth profile of damage structures was formed in a sample irradiated with dual (0.25 MeV H+ and 2.4 Me V O+) ion beams to a peak dose of 10.6 dpa, except that tiny cavities were formed down to the smaller depth of 0.5 μm. Depth profiles of implanted hydrogen atoms measured through a nuclear reaction analysis revaled that point defect mobilities were largely enhanced in the presence of hydrogen without helium. Upon annealing for 1 h at 1273 K, cavities grown to 70–80 nm at the maximum size were formed around peak damage regions in both the irradiated samples. Resultant cavity swellings were 6.2% and 18%, the ratio of which was found to be equal to that of accumulated damage.

The amplification characteristics of picosecond Gaussian pulses in conventional nontapered and both linear and exponential tapered-waveguide (TW) laser-diode amplifier (LDA) structures have been studied. The analysis is based on numerical simulation of the rate equation which also takes into account the effect of lateral carrier density distribution. The amount of pulse distortion experienced within the amplifier for input pulses having energies E/sub in/=0.1 E/sub sat(in)/=0.475 pJ (where E/sub sat(in)/ is the input saturation energy of the amplifier) and E/sub in/=E/sub sat(in)/=4.75 pJ have been analyzed for each structure which has a length of 900 /spl mu/m and an input width of 1 /spl mu/m. It has been found that the TW-LDA provides higher gain saturation and hence imposes less distortion on the amplified pulse as compared with a conventional nontapered LDA. The amplified 10-ps pulse used in this study experiences almost no broadening in the TW-LDA, whereas it suffers from broadening in the conventional nontapered LDA. The carrier density distribution and the dependence of the amplifier gain on the input pulse energy have also been studied for both nontapered and tapered amplifier structures. For example, in a TW-LDA with an output width of 20 /spl mu/m and a length of 900 /spl mu/m, the exponential structure provides 9-dB improvement in saturation energy as compared with the conventional amplifier. This improvement is about 10.5 dB in linear TW-LDAs.

The radiation-induced microstructural changes have been studied by cross-sectional transmission electron microscopy for single-crystal α-Al2O3 samples irradiated with triple ion beams (0.25 MeV H+, 0.6 MeV He+ and 2.4 MeV O2+; ‘Triple (A)’), (0.33 MeV H+, 0.45 MeV He+ and 1.3 MeV O+; ‘Triple (B)’) and three consecutive single ion beams (0.3 MeV H+ ion followed by 0.6 MeV He+ and then 0.8 MeV O+ ions) at 650°C to doses in the range 0.1–8.4 dpa at the damage peak. In the specimen irradiated with Triple (A), having the same average projected range to a total peak dose of 3.7 dpa, cavities with an average diameter of 13 nm were formed between 1.2 and 1.75 μm in depth causing a swelling of 0.1% at the peak, which is larger than those of the specimens irradiated with other conditions. The extent of the cavity-introduced region is some 40% smaller than observed in the damage region due to the He+ and the O+ ions and due to the H+ ions in the sample irradiated with Triple (B). Cavities formed in the sample irradiated with H+ ion beams were found to be inhomogeneously distributed in the vicinity of dislocation loops which were grown to loop sizes up to 80 nm.

Single crystal α-Al 2 O 3 specimens were irradiated with triple (0.25 MeV H + , 0.6 MeV He + and 2.4 MeV O 2+ ) ion beam, dual (0.25 MeV H + and 1.3 MeV O + ) ion beam and single ion beam (1.3 MeV O + ion irradiation followed by 0.25 MeV H + ion irradiation) at 650°C. In the specimen irradiated with the triple beam to a peak dose of 3.7 dpa, dislocation loops were distributed from the region very close to the surface to the depth of 1.8 μm, while cavities were formed at depths from 1.2 to 1.75 μm. Dislocation loops and cavities were not observed in the specimen irradiated with the dual beam. However, optical absorption spectroscopy for this specimen exhibited significant increase in intensity of absorption bands due to F and F + centers, which indicated production of oxygen vacancies by the irradiation. For the specimen subjected to the O + ion irradiation followed by the H + ion irradiation, no increase in the intensity of absorption bands was observed, although dislocation loops were densely formed at depths close to the projected ranges for each incident ion beams.

Conical microlenses have been fabricated directly on the end faces of single-mode fibres which demonstrate −1.8 dB coupling loss to a 0.82 μm laser diode. Experimental results on coupling loss, lateral and axial offsets are also reported.

Using a new method for reconstructing the depth profile of defects in an iondashirradiated sample by using slow positrons, the depth profiles of vacancy-type defects in 316 stainless steel samples, irradiated with 250 keV Ar ions to a dose of 7.5 × 10 19 m −2 at room temperature, have been calculated from Doppler-broadening S parameters measured as a function of positron energies up to 16 keV. Without assuming any type of shape for the defect profiles, such as Gaussian, the defect profiling is done using a least-squares fitting method. The resulting profile suggests that in as-irradiated 316 stainless steel samples with lower carbon content, the defect distribution peaks at a depth four times larger than that of the ion range. After annealing at a high temperature of 1253 K for 0.5 h, the fitted profile shows that the peak around the average ion range is highly enhanced. While in the steel added with 0.3 wt% titanium, the profile exhibits almost no peak after annealing at 1073 K. The results indicate that the radiationdashproduced vacancy clusters are stabilized by the implanted Ar atoms more effectively in the Ti-free steel than in the Ti-added steel.

Exponentially growing SQ-5 human lung squamous cell carcinoma cells were irradiated in vitro at 2-Gy per fraction per day continuously for 14 days. The number of total cells continued to increase exponentially till day 5, and reached a plateau level thereafter. The cell cycle distribution changed marginally for the first 5 days, and showed a prominent G2/M accumulation at day 7. Plating efficiencies decreased exponentially with increasing fractionation while the total clonogenic cell number remained constant until day 4. Radiosensitivity at each fraction was stable until day 9, but significantly increased at day 11. A comparison of plating efficiencies between the immediate and 24-h delayed assays revealed that the capacity of cells to spare 2-Gy damage increased with the number of 2-Gy fractions. These results suggest that sublethal damage could accumulate during multifraction daily irradiations, while repair of potentially lethal damage and/or proliferation could rather increase.

Thermolysis of the 3,6-diazabenzo [g] tricyclo [3.3.0.0 2,4 ]-octane (7) at 180 ° C resulted in rearrangement to give the pyrroloindole (9), whereas flash vacuum pyrolysis of the 6-aza-3-oxabenzotricyclooctanes (8) at 530 ° C resulted in both ring-expansion and rearrangement to afford the novel 4,1-benzoxazocines (10) and furoindoles (11)

A method for reconstructing the depth profile of defects in ion-irradiated samples with use of slow positrons is presented. The depth profiles of vacancy-type defects in the 116 stainless-steel sample irradiated with 250-keV carbon ions to a dose of 9.2×10 18 /m 2 at room temperature has been calculated from Doppler-broadening S parameters measured as a function of the positron energy. Without assuming any specific shape for the defect profiles, the defect profiling is made by a least-squares fitting method

Type 316 stainless steel and pure nickel were bombarded at ambient temperature with 1.0 MeV He-ions and 130 MeV Cl-ions, respectively. The cross sectional microstructure observed with a transmission electron microscope was compared with the damage profile calculated by using the extended E-DEP-1 computer code. The depth distributions of the dislocation loops and cavities in the He-ion bombarded stainless steel were in good agreement with the calculated displacement damage and injected helium distribution curves. The peak positions of the number density for the loops and cavities at depths of 1.53 and 1.60 um, respectively, agreed well with those of the calculated damage distribution curves at 1.57 and 1.66 μm from the bombarded surface. In the case of Cl-ion bombardment to pure nickel, the swelling peak appeared at a depth of 14μm which was 16% deeper than the displacement damage peak calculated to be 12.1 μm. The results indicate that the damage profile in He-ion bombarded stainless steel is described with the calculation using the extended E-DEP-1 computer code, at least up to an energy of 1 MeV. More accurate electronic stopping power is required to estimate the damage profile produced by heavy-ions with high energies.

We evaluated the effects of a novel pharmacological brain cooling (PBC) method with indomethacin (IND), a nonselective cyclooxygenase inhibitor, without the use of cooling blankets in patients with hemorrhagic stroke. Forty-six patients with hemorrhagic stroke (subarachnoid hemorrhage; n = 35, intracerebral hemorrhage; n = 11) were enrolled in this study. Brain temperature was measured directly with a temperature sensor. Patients were cooled by administering transrectal IND (100 mg) and a modified nasopharyngeal cooling method (positive selective brain cooling) initially. Brain temperature was controlled with IND 6 mg/kg/day for 14 days. Cerebrospinal fluid concentrations of interleukin-1beta (CSF IL-1beta) and serum bilirubin levels were measured at 1, 2, 4, and 7 days. The incidence of complicating symptomatic vasospasm after subarachnoid hemorrhage was lower than in non-PBC patients. CSF IL-1beta and serum bilirubin levels were suppressed in treated patients. IND has several beneficial effects on damaged brain tissues (anticytokine, free radical scavenger, antiprostaglandin effects, etc.) and prevents initial and secondary brain damage. PBC treatment for hemorrhagic stroke in patients appears to yield favorable results by acting as an antiinflammatory cytokine and reducing oxidative stress.

Brain damage is worsened by hyperthermia and prevented by hypothermia. Conventional hypothermia is a non-selective brain cooling method that employs cooling blankets to achieve surface cooling. This complicated method sometimes induces unfavorable systemic complications. We have developed a positive selective brain cooling (PSBC) method to control brain temperature quickly and safely following brain injury. Brain temperature was measured in patients with a ventriculostomy CAMINO catheter. A Foley balloon catheter was inserted to direct chilled air (8 to 12 L/min) into each side of the nasal cavity. The chilled air was exhaled through the oral cavity. In most patients, PSBC maintained normal brain temperature. This new technique provides quick induction of brain temperature control and does not require special facilities.

A stable model of neuronal damage after ischemia is needed in mice to enable progression of transgenic strategies. We performed transient global ischemia induced by common carotid artery occlusions with and without maintaining normal rectal temperature (Trec) in order to determine the importance of body temperature control during ischemia. We measured brain temperature (Tb) during ischemia/reperfusion. Mice with normothermia (Trec within +/- 1 degrees C) had increased mortality and neuronal cell death in the CA1 region of hippocampus, which did not occur in hypothermic animals. If the Trec was kept within +/- 1 degrees C, the Tb decreased during ischemia. After reperfusion, Tb in the normothermia group developed hyperthermia, which reached40 degrees C and was2 degrees C higher than Trec. We suggest that tightly controlled normothermia and prevention of hypothermia (Trec) during ischemia are important factors in the development of a stable neuronal damage model in mice.

NO is a putative neurotransmitter and neuromodulator in the brain. NO is not functioning as a direct neurotoxin. NO with the superoxide radical product peroxynitrite (ONOO-) is much more cytotoxic under tissue impairment conditions. Caspase-3, a potent effector of apoptosis that is triggered via several different signaling pathways, may play a very important role in neuronal cell death caused by various brain injuries. The relationship between mouse caspase-3 and peroxynitrite remains unclear. In the present study, we examined the in vivo expression of 3-nitrotyrosine (a metabolite of peroxinitrite) and caspase-3 after cerebral ischemia produced in a global ischemia model using mice (i.e., a cardiac arrest model). 3-nitrotyrosine immunoreactivity was detected in neuronal cells in the hippocampal dentate nucleus, and cortical regions starting at 12 hrs after ischemia. In particular, numerous neuronal cells were highly immunoreactive for 3-nitrotyrosine in the cortical regions. In hippocampal CA1 pyramidal neurons, 3-nitrotyrosine immunoreactivity was detected from 24 hrs. Caspase-3 immunopositive cells were observed in approximately the same area in which the positive reaction to the anti-nitrotyrosine antibody was observed. These results provide direct evidence for the induction of 3-nitrotyrosine and caspase-3 expression in vivo in an ischemia model using mice. The present findings suggest that peroxynitrite generated by cerebral ischemia/ reperfusion was strongly cytotoxic and induced neuronal cell death (apoptosis) mediated by caspase-3.

Choto-san is a kampo medicine that is widely used in patients with cerebral infarction, but the details of its mechanism of action remain unclear. We examined the neuroprotective effects of Choto-san using an experimental cerebral ischemia model (i.e., a rat cardiac arrest model). We also investigated the ability of Choto-san to eliminate or inhibit the activity of free radicals. It was found that Choto-san significantly prevents delayed neuronal cell death after ischemic reperfusion. Electron spin resonance demonstrated that the formation of hydroxyl- and superoxide-DMPO spin adducts were inhibited by Choto-san. The results of this study indicated that Choto-san prevents delayed neuronal cell death in the hippocampal CA1 region after ischemia. Direct free radical scavenging activity is among the pharmacological effects of Choto-san.

A method of generating an unique light beam, long range nondiffracting beam (LRNB) has been studied. The LRNB propagates over a long range keeping its narrow beam width as if it does not diffract, while general light beams spread by the diffraction effect. The new beam can be generated by a technique of wave front control. We will introduce some results of experiments and theoretical analyses of the LRNB generation using an optical system with a telescope and a laser.

The damage structures in Al/sub 2/O/sub 3/ after triple ion beam (H, He and/or N, O) irradiation were examined with cross-sectional TEM. Heavier ions penetration depths of He-and H-ions implantation enhanced growth of cavities produced by He- and H-ions, as compared with those produced by He-and H-ions only. Although peaks for He-implantation distribution are predicted by TRIM calculation to coincide with each other, cavity formation revealed the peaks to be separated appreciably.

The paper deals with the study of irradiation effects on the lithium metatitanate (Li/sub 2/TiO/sub 3/) ceramics. The simultaneous exposure of Li/sub 2/TiO/sub 3/ ceramics to H/sup +/, He/sup +/ and O/sup 2+/ ions was found to cause the appearance of anatase layer on its surface. The formation of the anatase is thought to be due to the displacement damage and electronic energy deposition. The irradiation of Li/sub 2/TiO/sub 3/ ceramics by 30 MeV O/sup 4+/ resulted in vanishing of grain structure near surface. This phenomenon is thought to be caused by the electronic energy deposition.

Cavity formations are completely suppressed in the 316 stainless steel sample irradiated with 1 MeV electrons at 823 K in a high voltage electron microscope after the implantation with 3.0 MeV He ions to 0.3 at.% at peak.

A 32b RISC microprocessor core for Digital TV SoC occupies 14.8mm/sup 2/ in 0.13/spl mu/m CMOS with six Cu layers. The core runs at 400MHz with 500mW average dissipation at 1.35V. The integrated 4.0GB/s 3/spl times/4 cross-bar bus switch improves sustained system performance efficiency by 1.75 times.

A conically-shaped microlens has been fabricated directly on the end face of a single-mode fibre (SMF) which demonstrates low coupling losses of -1.8 dB and -1.34 dB at the operating wavelengths of 0.82 /spl mu/m and 1.55 /spl mu/m, respectively. Experimental results on lateral and axial misalignments are also reported.