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Our purpose was to determine the effectiveness of vitrectomy in resolving the macular retinoschisis in an eye with glaucomatous optic neuropathy and also to determine the natural course of macular retinoschisis. This was a retrospective case series of patients who were diagnosed with macular retinoschisis and glaucomatous optic neuropathy. Fourteen eyes of 13 patients were studied. Patients with high myopia, vitreomacular traction syndrome, and the pit macular syndrome were excluded. There were three men and ten women, and 12 had unilateral and one had bilateral macular retinoschisis. Vitrectomy was performed for a serous retinal detachment, macular hole, or severe visual loss in five eyes. The mean follow-up time was 68.8 months in these five eyes, and the macular retinoschisis was resolved and the best-corrected visual acuity (BCVA) at the final visit was significantly improved in all eyes (P = 0.007). However, two of these fiv e eyes developed a macular hole and required a second vitrectomy. Of the nine eyes without treatment with a mean follow-up time of 29.0 months, the BCVA at the final visit remained unchanged from the baseline BCVA in all eyes. The macular retinoschisis was resolved or reduced in three eyes without treatment. Vitrectomy was effective for the resolution of macular retinoschisis in eyes with glaucomatous optic neuropathy and serous retinal detachment or macular hole or severe reduction of the BCVA. Macular retinoschisis can be resolved without a reduction of the BCVA in some cases without treatment.

Background & aims To improve prognosis in patients with hepatocellular carcinoma (HCC), the molecular mechanisms of tumor thrombus formation and metastasis must be clarified. The epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) play crucial roles in tumor invasion and metastasis. This study aimed to reveal the clinical significance of the expression of the functional CSC marker, CD13, and investigate the correlation between CD13 expression and two EMT markers, E-cadherin and vimentin. Methods We acquired clinical samples from 86 patients with HCC that underwent radical liver resections. We performed immunohistochemistry to evaluate CD13, E-cadherin and vimentin expression. We investigated the relationships among protein expression levels, clinicopathological factors and prognosis. Results Based on CD13 expression, patients were categorized into CD13high (n = 30, 34.9%) and CD13low (n = 56, 65.1%) groups. The mean tumor size was significantly larger in the CD13high group than in the CD13low group (P = 0.049). Compared with the CD13low group, the CD13high group showed significantly earlier recurrences and shorter survival times. In the multivariate analysis, CD13high was an independent prognostic factor for overall survival (hazard ratio, 1.98; P = 0.044). The disease-free survival time was shorter in the vimentin-positive group than that in the vimentin-negative group (P = 0.014). In an analysis of the relationship between CD13 and EMT, there was no significant correlation between CD13 and EMT markers. Conclusions Our findings suggested that CD13 enrichment was correlated with early recurrences, and poor prognosis in patients with HCC and that vimentin was associated with early recurrences. CD13 represents a potential therapeutic target for HCC, because CSC regulation and EMT suppression are essential in cancer therapy.

Background Giant cell arteritis (GCA) is a granulomatous vasculitis and targets large vessels with predominance for the aortic arch and the cranial branches. GCA with cranial symptoms shows headache, jaw claudication, and ophthalmologic symptoms and thus was previously called temporal arteritis. Recently, cases of GCA without cranial manifestations and extracranial GCA have been reported. Case presentation A 76-year-old woman was referred to our hospital complaining of sudden abdominal pain and high fever. Her present history of illness did not show any cranial symptoms such as headache, visual disturbance, or stroke. CT images showed severe thickening of the small intestinal mesentery and massive ascites. She was diagnosed to have acute abdomen probably with gastrointestinal perforation and underwent the emergent laparotomy. Excisions of a 60-cm length of the jejunum including the thickening mesenteric lesion were carried out. Marked hypertrophy of the vascular intima and mild stenosis of the arterial lumen were displayed with infiltration of lymphocytes, neutrophils, and eosinophils. Scattered multinucleated giant cells on the endothelium, in the intima, media, and adventitia were demonstrated. Elastica van Gieson stain showed focal loss and fragmentation of the internal elastic lamina. Histopathological examinations showed typical GCA. Her postoperative process was uneventful without any symptoms, and she was followed as an out-patient prescribed with daily doses of 40 mg of prednisolone. Conclusions We hereby report a rare case of mesenteric involvement in GCA without cranial manifestations and elucidate the histopathological features of extracranial GCA in arteries as well as veins and jejunum.

Purpose To evaluate real-world evidence for intraocular pressure (IOP) elevation after subtenon triamcinolone acetonide injection (STTA) in 1252 Japanese patients (1406 eyes) in the Japan Clinical REtina STudy group (J-CREST). Methods This was a multicentre retrospective study of the medical records of 1252 patients (676 men (758 eyes); mean age: 63.8 ± 12.9 years) who received STTA in participating centres between April 2013 and July 2017. Results IOP elevation was observed in 206 eyes (14.7%) and IOP increase ≥ 6 mmHg was found in 328 eyes (23.3%). In total, 106 eyes (7.5%) needed medication and two eyes (0.14%) needed surgical procedures. Younger age, higher baseline IOP, and steroid dose were risk factors associated with IOP elevation. Risk factors associated with IOP increase ≥ 6 mmHg were younger age, lower baseline IOP, steroid dose, and higher incidences of diabetic macular oedema (DME) and uveitis. In contrast, with steroid dose fixed at 20 mg, a lower incidence of DME was a risk factor for increased IOP, suggesting that STTA had dose-dependent effects on IOP increase, especially in patients with DME. Conclusion Our real-world evidence from a large sample of Japanese patients who received STTA showed that the incidence of IOP elevation after STTA was 14.7%, and was associated with younger age, higher baseline IOP, and steroid dose. Thus, IOP should be monitored, especially in patients with younger age, higher baseline IOP, and higher incidences of DME and uveitis.

To quantify the changes of the choroidal structure in the enhanced depth imaging optical coherence tomographic (EDI-OCT) images after intravitreal aflibercept (IVA) injections for polypoidal choroidal vasculopathy (PCV).Retrospective, observational case series. Forty eyes of 40 treatment-naive patients who underwent IVA for PCV were examined by EDI-OCT before, and 3 months and 12 months after IVA. The EDI-OCT images were binarised by ImageJ software. The cross-sectional luminal and stromal areas of the inner and outer subfoveal choroid of 1500 µm width were quantified.The stromal but not the luminal area of the inner choroid was significantly decreased at 3 months and 12 months after the IVA (stromal area, both p0.001; luminal area, both p0.050). On the other hand, the luminal but not the stromal area of the outer choroid was significantly decreased at 3 months and 12 months (luminal area, both p0.001; stromal area, both p0.050). The Pachychoroid Index, ratio of luminal/stromal area (L/S ratio) of the outer choroid divided by the L/S ratio of the inner choroid, was significantly decreased at 3 months and 12 months (both p0.050). The Pachychoroid Index was increased and returned almost to the baseline level after recurrences and decreased again after successful re-treatment. The baseline Pachychoroid Index was significantly correlated with the presence of a dry macula, thinner fovea and better visual acuity at 12 months (all p0.050).The binarisation of the EDI-OCT images can be used to quantify the activity of PCV and to predict the prognosis after IVA.

A 1-D and 2-D Daubechies 5 (db5) discrete wavelet shrinkage methods using a 10 level decomposition was applied to white light lidar data particularly at 350 nm and 550 nm backscattered signal. At 350 nm, the backscattered signal is very weak as compared to 550 nm backscattered signal because of the spectral intensity distribution of the generated white light. The 1-D and 2-D wavelet shrinkage method gave a much better result as compared with the moving average method. However, the 2-D wavelet shrinkage method produced a much better denoised lidar signal compared with the 1-D wavelet shrinkage method. This is indicated by the 142% increase in correlation coefficient between the 2-D denoised lidar signal and the 800 nm original lidar signal as compared with only 12% increase in correlation coefficient for the 1-D denoised lidar signal. The 2-D wavelet shrinkage method also gave a much higher SNR value of 65.9 compared to 1-D which is 38.8.

Direct-drive implosion experiments on the GEKKO XII laser (9 kJ, 0.5 μm, 2 ns) with deuterium and tritium (DT) exchanged plastic hollow shell targets demonstrated fuel areal densities (ρR) of ˜0.1 g/cm2 and fuel densities of ˜600 times liquid density at fuel temperatures of ˜0.3 keV. (The density and ρR values refer only to DT and do not include carbons in the plastic targets.) These values are to be compared with thermonuclear ignition conditions, i.e., fuel densities of 500–1000 times liquid density, fuel areal densities greater than 0.3 g/cm2, and fuel temperatures greater than 5 keV. The irradiation nonuniformity in these experiments was significantly reduced to a level of ρR was directly measured with the neutron activation of Si, which was originally compounded in the plastic targets. The fuel densities were estimated from the ρR values using the mass conservation relation, where the ablated mass was separately measured using the time-dependent X-ray emission from multilayer targets. Although the observed densities were in agreement with one-dimensional calculation results with convergence ratios of 25–30, the observed neutron yields were significantly lower than those of the calculations. This suggests the implosion uniformity is not sufficient to create a hot spark in which most neutrons should be generated.

Laser pulses with high repetitive rate generated from a Q-switch microchip Nd:YAG oscillator were amplified by Active mirror composed of Nd/Cr:YAG ceramic pumped by CW arc-lamp. The laser pulses were amplified, and saturation of averaged output laser power was observed. Repetitive ratio of injected laser pulses was changed from 20 to 100 kHz. Averaged output laser power and gain were measured, and gain coefficient and power-extraction efficiency were evaluated. Output laser power was calculated and compared to experimentally measured one, and the calculated results are consistent with the experimental ones. For amplification of laser pulses with high repetitive ratio, this laser material can realize very high laser gain with low pumping power density and high optical–optical conversion efficiency under CW-lamp-light pumping.

Laser pulses generated in a laser oscillator were amplified by Nd/Cr:YAG ceramic amplifiers. The saturation of output-laser energy was experimentally observed. We found that the stimulated emission cross-section of Nd/Cr:YAG ceramics was effectively increased and the saturation fluence was effectively reduced to 0.1 J/cm 2 due to the energy transfer between excited Cr and Nd ions. The output-laser energy we calculated was compared with the experimental ones and the extractable stored energy in the Nd/Cr:YAG ceramics was evaluated. This laser material is suitable for high-repetition-rate operations because of the high laser gain with low pumping intensity and low effective saturation fluence.

The concept of an Active mirror with transparent Nd/Cr:YAG ceramics is proposed. A new ceramic material pumped by an arc-metal-halide lamp has been experimentally implemented. CW-laser light generated in a 1064 nm Nd:YAG micro-tip oscillator was amplified by an Active mirror made of Nd/Cr:YAG ceramic and pumped by CW arc-lamp light. The saturation power density of the Nd/Cr:YAG ceramic was lower than that of Nd:YAG because the stimulated-cross-section and lifetime were effectively enhanced by the sensitization of Cr ions. The maximum output laser power while keeping spatial beam quality was up to 3 W with an input lamp power of 9 W; the resulting optical–optical conversion efficiency of 33% was close to the theoretical prediction of nearly 50%.

Electron spin resonance (ESR) analyses of quartz grains in fault gouge were performed for a core sample taken from the Nojima Fault that moved during the 1995 Kobe earthquake (Hyogo-ken Nanbu earthquake). Distribution of radiation-induced defects in the gouge at a depth of 389.4 m was measured by extracting quartz grains from seven discrete positions within 30 mm of the fault plane on the granite side. The decrease in E′1 and Al centers was observed within 2 mm of the fault plane, suggesting partial annealing due to faulting. Partial annealing even at that depth suggested that conventional ESR dating, which is based on the hypothesis of complete annealing during faulting, was not applicable. Theoretical calculations of the temperature rise and of the thermal annealing of defects have been made by assuming a simple annealing model of heat generation on the fault plane. Thermal energy was calculated to have been approximately 8 MJ/m2 to explain the profile of the heat-affected region. Thermal energy was much larger than the one estimated from hydrothermal solution, and corresponded to the frictional heat calculated for a normal stress of 20 MPa, a displacement of 2 m, and a frictional coefficient of 0.2.

A new concept to derive particle information from depolarization ratios obtained by a simultaneous three-wavelength depolarization lidar was presented. This new data treatment utilized the wavelength dependence of the ratio of the polarization components in the scattering light based on T-matrix computation. The results showed that calculated three-wavelength depolarization ratios can be used to characterize particle sizes of ice particles. Assessing the mixing of spherical and nonspherical aerosols, the presented method successfully reproduced the lidar data in real.

We carried out depolarization light detection and ranging (LIDAR) measurements for the first time using a coherent white light continuum with multi-wavelength backscatter measurements. The white light continuum from the UV to the IR region was generated in Kr gas by a terawatt femtosecond laser system. The LIDAR system consisted of a depolarization channel at 450 nm and the five-wavelength Mie scattering channels at 350, 450, 550, 700, and 800 nm. This technique can potentially open a promising avenue toward simultaneous depolarization LIDAR at multi-wavelength.

Adsorption of Gd3+ and Mn2+ into hydroxyapatite (HAP (Ca5(PO4)3(OH)2)) was studied by ESR, ion chromatography and ICP-AES to investigate the U-uptake model. HAP absorbed Gd3+ via a cation exchange reaction and resulted in a signal width of 240 mT. The growth of the thermally stable Gd3+ signal in HAP was also fitted by saturation and diffusion equations. The ESR signals of Gd3+ and Mn2+ were observed overlapping the CO2− signals, however, the dose–response curves of the CO2− signal were similar to that of control HAP.

A scanning electron spin resonance (ESR) microscope using a localized microwave field was redesigned to measure ESR spectra from 0 to 400 mT using electromagnets. Divalent copper ion (Cu2+) in copper sulfate pentahydrate (CuSO4·5H2O) was imaged, after the powdered samples were cemented in silicone rubber under a magnetic field. The ratio of the two signal intensities at g = 2.27 and 2.08 clearly indicates the orientation of the particles. This method can be used for mapping the local magnetic field and its direction.

Compression of plasmas with laser pulses in the 10-kJ range produced densities in the range of 1000 times that of the solid state, where however the temperatures within a few hundred eV were rather low. This induced the fast ignitor scheme for central or peripheral deposition of some 10-kJ ps laser pulses on conventional $n_{\rm s}$-precompressed DT plasma of 3000 times solid-state density. We present results where the ps ignition is avoided and only a single-event conventional compression is used. Following our computations of volume ignition and the excellent agreement with measured highest fusion gains of volume compression, we found conditions where compression to 5000 times that of the solid state and by using laser pulses of 10 MJ produce volume ignition with temperatures between 400 and 800 eV only for high-gain volume ignition.

Electrically stimulated luminescence (ESL) of calcium carbonate has been studied for application as dosimetry and dating. A powdered calcium carbonate was sandwiched by electrodes, which supplied electric field. Luminescence and surface current through a powdered sample were measured using a photomultiplier and a digital multimeter, respectively. A linear dependence of ESL on the absorbed dose by γ -rays was found when the applied voltage was below the breakdown threshold. Reciprocal electric charges through the sample had also linear relation with the absorbed dose. We propose that the luminescence and electric charge under intense electric field in calcium carbonate become new methods for dosimetry and dating on the basis of the surface defects of the calcium carbonate grains produced by the irradiation of γ -rays.

Many of the pebbles and cobbles found in the ∼5000-km 2 ‘upland deposits’ of eastern Virginia and Southern Maryland (USA) are decorated with external flanges of hard red–brown material with uniform thicknesses ∼5 mm terminated by crisp conchoidal fracture surfaces. Thirteen high-grade sandstone (quartzite) pebbles and cobbles exhibiting such features were cut with rock saws, revealing that the external flanges are contiguous with undulating red–brown bands of about the same thicknesses extending all the way through their interiors and, in several cases, that these interior bands are approximately parallel to spalled surfaces and/or internal fractures. These rocks have been studied by thin-section photomicroscopy, scanning electron microscopy, extended X-ray absorption fine structure (EXAFS), X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron-spin-resonance imaging, and Mossbauer spectrometry. The EXAFS, XRF, XRD, and Mossbauer data combine to demonstrate that the hard red–brown materials contain goethite (α-FeOOH) in particle sizes ∼100–150 A with impurity contents ⩽5%. It is not ruled out that these materials may also include an amorphous-ferric-oxyhydroxide component with short-range order constrained by the EXAFS to be similar to that in goethite. The origin of the upland deposits has long posed a riddle to geologists. And the geometry of the red–brown bands internal to the present rocks (not explainable by aqueous diffusion) now confronts materials scientists with a puzzle. We propose that the solutions to both the riddle and the puzzle may be linked to the effects of the known impact of an extraterrestrial object 35.5 million years ago into the area that is now the Chesapeake Bay (CB) on the US Atlantic Coastal Plain. We strengthen this proposition with (1) critical reconsideration of the previously accepted geological explanation of the upland deposits, (2) an assessment of the probable natures of the materials present in the CB-crater target area that would have become ejecta, (3) a review of the pertinent physics of impact cratering, (4) the detailed studies of the rocks mentioned above, and (5) a preliminary study of a sample of goethite subjected to experimental shocking. Based on these considerations, the hard red–brown materials of the upland deposits are proposed to have been quenched from molten sheets of Fe-oxyhydroxides generated by impact-induced shock waves passing through water rich in suspended ferric-oxyhydroxide particles. A model for the physics of this process is presented. It is reasonably assumed that iron-rich ground waters were present in aquifers extending into the ∼500-m-deep accumulation of quartz-based sediments known to have been in the target area of the CB impactor. Penetration of the molten Fe-oxyhydroxide sheets into the quartzite cobbles is ascribed to opening of interstitial spaces between the constituent sand grains by action of reverberating pressure and rarefaction components of the same shock waves that boosted these rocks to their present-day upland locations.

The adsorption of Gd3+ into sediments was studied by electron spin resonance (ESR) to investigate the uranium uptake model and the migration of harmful elements into sediments in nuclear waste repositories. The ESR signal in montmorillonite immersed in GdCl3 solution was ascribed to Gd3+ observed at g=2.0 with a width of 48 mT . This signal saturated with the concentration of GdCl3 solution from 0.01 to 0.1 mol / l . The ESR signal decayed with a lifetime of 750 s and different ESR signals at g=5.6 and 2.9 appeared in isothermal annealing experiments at 150°C. These changes are caused by the change of the environment around Gd3+ ion to an anisotropic field due to dehydration and shrinkage of the montmorillonite structure. The adsorption of Gd3+ on hydroxyapatite (HAP) occurred via a cation exchange reaction and resulted in a broad signal with a width of 240 mT . The thermally stable Gd3+ signal in HAP also saturated with the concentration of the solution from 0.01 to 0.1 mol / l .

Reflectance spectra of S-type asteroids are different from those of ordinary chondrites. This spectral mismatch is explained by space weathering processes, where high-velocity dust particle impacts change the optical properties of the uppermost regolith surface of asteroids. S-type asteroids exhibit more overall depletion and reddening of spectra, and more weakening of absorption bands relative to ordinary chondrites. Nanophase metallic iron particles, which are formed through vapor deposition from dust impact heating, are considered as the most essential cause of space weathering. In this study, we describe the spectral changes of olivine and pyroxene using nanosecond pulse laser irradiation and the presence of nanophase metallic iron particles in laser-irradiated materials by transmission electron microscopy (TEM) and electron spin resonance (ESR). The irradiated spectra of the samples show a reduction of the overall spectra (250–2600 nm) and a reddening with weakened absorption bands. Nanophase metallic iron particles were found not only in laser-irradiated olivine samples, but also in laser-irradiated pyroxene samples by TEM. Strong ESR signals, which derive from nanophase iron particles, are observed in the irradiated olivine samples. Moreover, ESR intensities increase with the space weathering degree simulated as laser irradiation time. One possible application of space weathering is the estimation of the relative age of asteroids using the relation between optical effects and quantities of produced nanophase iron particles.

Optically stimulated luminescence (OSL) and thermoluminescence (TL) for γ-irradiated ice samples have been investigated as future dating techniques for icy bodies in the solar system. The OSL around 400 nm lasted more than 600 s for γ-irradiated H2O ice and D2O ice under 623-nm-light stimulation at 90 K; the latter was used to study the migration of hydrogen atoms. A defect containing trapped electrons is the most suitable explanation of the OSL emissions. The intensity of the TL peak at 120 K increased linearly with γ-dosage increasing up to 15 kGy for both D2O ice and H2O ice. Intensities of both OSL and TL for D2O ice were larger than those for H2O ice. The TL peak related to H2O was observed but its thermal characteristics did not agree with those of OH and HO2 radicals measured by ESR. The OSL method should be employed in future surveys in the solar system.

We examined the applicability of Raman spectroscopy as a laser remote sensing tool for monitoring the gases dissolved in water and gas bubbles. A frequency doubled Q-switched Nd:YAG laser (532 nm) is irradiated to CO2 gas bubbles generated by an air pump. The Raman signals at 1383 cm-1 from CO2 and 1645 cm-1 from water were detected. It has been shown that the CO2/H2O Raman signal ratio is dependent on the CO2 bubble rate.

Optically stimulated luminescence (OSL) of synthetic stishovite was investigated for a future dating technique of meteor impact craters. Luminescence around 330 nm was measured on the γ-ray irradiated stishovite under two stimulating light sources of infrared laser (830 nm) and blue light emitting diode set (470 nm). Thermoluminescence (TL) studies before and after the OSL measurements showed the intensities around 100–200°C and 220–350°C to increase and those around 350–450°C to decrease. This indicates that a part of deep-trapped charges excited during the OSL measurements were retrapped by shallower traps. The infrared stimulated luminescence (IRSL) after the TL measurement up to 450°C could not be detected, while the blue light stimulated luminescence (BLSL) after TL had about one-tenth of the intensity before TL. This indicates that a part of the charges in shallower traps were detrapped thermally and returned to the deeper traps which were related to BLSL. The result implies that some of the BLSL-related traps are quite stable at room temperature and could be used for geological dating. In addition, two paramagnetic centers produced by sudden release of high pressure in synthesis process were found in the unirradiated stishovite by electron spin resonance (ESR). Their g-factors are g∥=2.00181 and g⊥=2.00062 for an axial signal and g=2.00305 for the other isotropic signal. These signals could be used for an evidence of impacts if those signals could be stored in geological time.

Numerical simulation and analysis of the output stability of optical parametric amplification process versus pump intensity variations are presented. It is shown that there exists an optimal working point where excellent stability can be achieved by properly balancing relevant system parameters within certain ranges of pump variations.

The right strategy for finding a new ESR dosimetric material sensitive to radiation is to follow the orthodox procedures used in the development of thermoluminescence dosimeters (TLD) and phosphorescence studies. Modern procedures used in materials sciences, such as computer calculation of molecular orbitals (MO), should be employed to estimate the ESR and optical properties of prospective materials. Radiation effects in lithium and magnesium sulfates and metal salts of organic acids, such as lithium and magnesium lactates, have been investigated in search for tissue-equivalent dosimeter with a large G value.

We are planning a short wavelength FEL experiment combining a micro-wiggler and an X-ray seed pulse. A micro-wiggler makes it possible to lase in the VUV to soft X-ray region using a low-energy electron beam. The development of the micro-wiggler is almost complete. With an intense X-ray seed pulse, quick start-up is expected making the wiggler length short. For the seed X-ray source we will use laser-produced Plasma. The validity of this concept was verified using a simulation code based on the SDE-method. With 10 kW X-ray power for seeding the saturation position is shortened to 5 m.

Thermal dependence on the small signal gain of Nd/Cr:YAG (yttrium aluminum garnet) ceramics was observed experimentally. Usually, Nd:YAG crystal and ceramics have remarkable gain reduction when optical pumping is performed and the temperature of the laser media is upped to 373 K. A CW laser light generated in a 1064 nm Nd:YAG laser oscillator was amplified by Nd/Cr:YAG ceramic amplifier, and the output power was measured at non-saturation level. Laser small signal gain of the ceramic disk was kept to 470 K. This property was remarkably different from one of Nd:YAG crystals or ceramics. The peak shift of the fluorescence was observed experimentally when the temperature is high.

We performed a lidar observation of Asian dust aerosols for the first time using a white light lidar system. The lidar used in the observation utilized a coherent white light continuum generated in Kr gas as a light source and was used as a three-wavelength Mie-scattering lidar having a depolarization measurement capability at 450, 550, and 800 nm. Lidar depolarization ratios of 0.30?0.70 at 800 nm were measured. These data reveal a higher depolarization ratio than usual (normally almost zero) in the lower troposphere. Thus, the white light lidar can identify Asian dust particles that pose a threat to cross-border pollution in Japan.

The recent high core gains of 29% in laser fusion experiments at the LLE Rochester are evaluated and compared with related earlier measurements where surprisingly the self-similarity model for volume compression provides a common description. This is a proof that the isentropic conditions of stagnation-free compression were mostly fulfilled at the optimized experimental gains, in contrast to highly entropy-producing shock and central spark conditions. Some projections are given of how these results may be generalized to volume ignition for the parameters of the NIF (National Ignition Facility). The proof of stagnation-free volume compression for the best laser fusion gains indicates the advantages of volume ignition, which not only is ‘robust’ and simply follows the natural adiabatic compression, but also is much less sensitive to instabilities and mixing. However, its essential advantage is that it is free from symmetry problems – in contrast to spark ignition, with its spherical detonation front.

From laboratory experiments, we observed that unloading stress on a piece of granite induced a pulsed electric potential variation, which decays exponentially with a time constant ranging from 1.5 to 4.0 s. The electric potential variation depends on the magnitude and the sustaining time of applied stress, indicating that the variation is due to piezoelectricity and migration of bound charges that compensate the piezoelectric polarization. An apparent piezoelectric coefficient of granite was obtained to be about 1.4 × 10−15 C/N, three orders of the magnitude smaller than that of a single crystal of quartz.

To enhance the FEL harmonic gain, we have developed a wiggler having a harmonic wiggler field. The modified wiggler consists of a conventional planar wiggler and high-permeability shims. Because of this simpleness, we can develop a wiggler having various types of modified fields, easily and economically. We show the design basis of the modified wiggler and examples of them which contain one harmonic field. Then, we introduce the FEL experiment of the 5th harmonic generation with a modified wiggler.

An electromagnetic helical microwiggler with three poles per period, employing permanent magnets to suppress leakage flux in the vicinity of the gap, has been developed. The wiggler is embedded in a double-walled vacuum chamber with a water jacket for heat removal. The field profile consists of a 30-period-long uniform-field section terminated at both ends with 5-period-long tapered fields. A peak on-axis field of 3.0 kG was achieved with a period of 7.9 mm and a gap diameter of 4.6 mm. An optimal sorting technique was applied to the permanent magnets to minimize variations in the peak field amplitude. Based on measurements of the test wiggler, rms amplitude variations of 1.4% and 2.6% in, respectively, the horizontal and vertical field amplitudes were attained.

Metals or metal compounds as photocathodes provide high current density and have high damage threshold for laser irradiation. In addition, the quantum efficiency of these cathodes are enhanced by heating up [1]. The tungsten photocathode heated up to 1400 K and irradiated by 2ω (532 nm) of Nd:YAG laser produced the electron beam with high current density (∼1 kA/cm 2 ) and quantum efficiency was about 10 −5 . In order to further improve the quantum efficiency of the tungsten, it is necessary to instantly increase the temperature above 1400 K without thermal damage of RF gun. Fundamental (1064 nm) of Nd:YAG laser that is uncoverted portion of the laser pulse can heat up the cathode instantly. When the fundamental of 20 ps pulse length irradiates the cathode, peaked temperature is estimated to be after 11 ps of the peak of laser pulse. We irradiated the tungsten photocathode by two wavelengths with time interval between ω and 2ω.

We have used thin sections of an archaeological tooth sample to obtain spatially resolved ESR spectra using a pin-hole cavity. This study presents the first ESR images of naturally generated radiation sensitive signals. The 3-D plots of the natural and irradiated samples show strong variations of the ESR intensities within the enamel layers. Owing to the relatively large scattering of the data points it has not been possible to produce 3-D dose plots.

Thermoluminescence (TL) and optically stimulated luminescence (OSL) of the Allende meteorite have been studied using infrared CO 2 laser light as a heat source and HeNe laser light to excite the material, respectively from a long distance. New techniques of remote TL (R-TL) and remote OSL (R-OSL) have been developed for future remote dating from a long distance in a planetary survey. The upper limits of the distance for R-TL and R-OSL were estimated using the laboratory TL signal of the meteorite peaking at 320°C: about 400 photons s −1 for the R-TL and 60 photons s −1 for R-OSL at a distance of 1 km using a laser beam with the divergence of 0.1 mrad at powers of 100 and 1 W, respectively. An age limit of 10 5 or 10 6 years due to the signal saturation and the objects heterogeneity, as expected from previous studies, may make the asteroid survey difficult but would still help to investigate the surface activities of icy planets and satellites in outer planet worlds.