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In implosion experiments of a cone-guided target using Gekko XII laser, the lasers on the cone side are not irradiated to avoid the irradiation of the cone. In such condition, the implosion process is done highly asymmetrically. Thus we evaluated the effects of the asymmetric implosion on the compression ratio of the fuel in Gekko XII irradiation orientation by three-dimensional hydro simulations. In this paper, we discuss the degradation of the compression ratio by asymmetric implosion and show that the compression ratio can be enhanced by adjusting the laser intensity between each beam to reduce the asymmetry of the implosion.

This paper reports an experimental investigation of a scheme to produce an intense, pulsed, point-like, and quasi-monoenergy neutron source. In this scheme, the inner wall of a deuterated plastic spherical cavity is mono-directionally irradiated by a 2.4 kJ laser beam through an open-tip gold cone inserted into the cavity. The whole inner wall of the cavity is illuminated by laser light owing to multiple laser reflections, and the laser-ablated plasma stagnates near the center of the cavity, at which a several keV hot spot is generated. Thermonuclear and beam D-D fusion reactions occur in the hot spot. We have demonstrated the neutron yield exceeding 107 neutrons per pulse from a

To investigate both the optical and electrical properties of InN, we have measured the infrared reflectance spectra of InN thin films and performed the fitting analyses of the infrared spectra to obtain not only phonon frequencies and the damping factors but also the carrier concentration of InN. In this paper, we extend the aim of those analyses to the electron mobility and demonstrate that the temperature dependence of the electron mobility can be discussed using the infrared reflectance spectra analyses.

Micro optical reflecance measurements of InN films have been performed at middle and near infrared region. Spectrum line shape fitting calculation based on theoretical formula which takes account of the coupling between LO phonons and plasmons have been also performed. Small area reflectance spectra (50 μm × 50 μm) at every points in the field of microscope vision show both similar and different line shapes by wavenumber location. The different part is mainly responsible for plasmon relaxation time which directly correspond to the carrier mobility. Comparison among contour image map of the fitting parameters and visible image is also presented. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A new method of degenerate four-wave mixing is demonstrated. This method uses nanosecond optical pulses from an optical parametric oscillator (OPO) that has a broad bandwidth. The OPO uses a β-BaB2O4 crystal that has a coherence time from 60 to 800 fs and the OPO wavelength can be tuned from 410 to 2600 nm. This Letter also reports the signal decay time constants that correspond to the energy relaxation time constants for plasmon absorption in Au nanocrystals dispersed in Al2O3 films, for absorption in vanadyl oxophthalocyanine microcrystals dispersed in water, and for absorption in a nitrobenzene solution of 4-(N,N-diethylamino)-β-nitrostyrene.

A new approach is applied to the analyses of thermal effects in ARXPS (photoelectron diffraction) spectra, where we include both spherical wave correction and anharmonic vibration effects. A partial summation technique is applied to get a plane wave part and a spherical wave part(dynamical spherical wave effect ). Numerical calculations illustrate the importance of the spherical wave effects in high energy ARXPS spectra. In particular the spherical wave effects play an important role in the small-angle scatterings which predominate in the ARXPS processes. In comparison with the dynamical spherical wave effects in EXAFS those in ARXPS only reduce the intensities whereas the phase is unchanged.

In this work we have applied a new approach developed by us to the analyses of thermal effects in ARXPS spectra, where we include both spherical wave correction and anharmonic vibration effects based on Brouder's Lie group formulas. We apply partial summation technique to get a plane wave part which does not disappear even for large kR limit, and a spherical wave part which disappears for that limit. Numerical calculations illustrate the spherical wave effects in ARXPS spectra.

In direct drive laser fusion, the non-uniformity of the laser absorption on the target surface caused by the irradiation of a finite number of laser beams is a sever problem. GekkoXII laser at Osaka University has twelve laser beams and is irradiated to the target with a dodecahedron orientation, in which the distribution of the laser absorption on the target surface becomes non-uniform. Furthermore, in the case of a cone-guided target, the laser irradiation orientation is more limited. In this paper, we conducted implosion simulations of the cone- guided target based on GekkoXII irradiation orientation and compared the case of using the twelve beams and nine beams where the three beams irradiating the cone region are cut. The implosion simulations were conducted by a three-dimensional pure hydro code.

After photodarkening, colored filter glasses obtained from different glass makers show energy relaxation times that depend on dopant components in the glasses. Dopant analysis implies that potassium ions may affect the energy relaxation time shortening. In order to observe dopant dependence of the darkening, laser wavelengths are adjusted to the same absorption in all samples. CdSxSe1−x microcrystallite sizes in this report are confirmed not to affect the energy relaxation times.

It is clearly shown that a nanosecond pulse dye laser can provide the same photodarkening effect in colored filter glasses as a picosecond hybridly mode-locked dye laser. This suggests that the photodarkening mechanism is associated with a kind of solarization and a state of surface activation due to the production of a snowball comprised of impurity ions around CdSxSe1−x micro- crystallites. It is also shown that the laser annealing effect is the same as the photodarkening effect.

A new technique utilizing the double refraction walk-off of a precisely cut pair of KTP crystals and a mode-locked Nd:YAG laser to obtain efficient second harmonic generation (SHG) is reported for the first time. This technique leads to a fourfold increment in second harmonic output power compared with that of a single crystal and would open up a number of potential new applications.

Middle-term perspectives of process-device technology of semiconductor integrated circuits are described. Even though Moore's law is generally considered to hold good for 10-15 years more, many of the current technologies are foreseen to face growth limitations and thus undergo innovative changes. Problems and possible breakthroughs are discussed for lithography, transistor size, interconnections and power dissipation as the principal factors of such limitations. Future directions to expand functionality and performance of integrated circuits are also described.

SummaryLaparoscopic omental patch repair for perforated duodenal ulcer is still technically complicated and requires a long time because of the lack of appropriate laparoscopic techniques and instruments. Therefore, we have designed a new technique for laparoscopic omental plug repair in order to simplify these surgical procedures, and obtained good results with this method.

Hashimoto's thyroiditis (HT) is an autoimmune disease of the thyroid gland, and like many other autoimmune diseases, it is associated with the HLA and CTLA-4 gene. We have examined the distribution of the HLA DRB4*0101 allele and a CTLA-4 exon 1 A/G polymorphism in Japanese HT patients and controls and investigated possible interactions of these genes with thyroid function. Seventy Japanese HT patients and 105 controls were included in this study. HT was diagnosed on the basis of positivity for thyroid peroxidase (TPO) autoantibodies and the presence of a palpable diffuse goiter. Genotyping was performed by polymerase chain reaction (PCR)-based methods. CTLA-4-GG or -AG was more prevalent in the patients, and the odds ratio for the G allele was 4.95. The frequency of DRB4*0101-positive individuals was significantly higher in HT (odds ratio=2.17). The TSH values of HT patients at the time of diagnosis were compared to CTLA-4 genotype and HLA-DRB4*0101 positivity. They were slightly higher in the CTLA-4-AG group than in the -GG group and significantly higher in the HLA-DRB4*0101-positive group than in the -negative group (p

The spatial organization of cortical neural activities is one of the most important elements linking neural network models and natural neural networks. The columnar organization indicated by several works suggests a strong spatial constraint on neural network functions. Recently, attention has grown on the correlation between a vigorous firing of a particular neuron and the "supporting" neural firings in the cortical vicinity. Here, we investigate the relation between a vigorous firing of a particular neuron and the surrounding neural activities using a generic neural network architecture. We analyze the the spatial firing pattern in the vicinity of a particular neuron when the neuron is firing vigorously (preferred cortical state, PCS). We find that the spatial heterogeneity of the PCS is more pronounced in the both extreme ends of activity scale, and not so much in the intermediate activity region. This result, taken together with an analysis of the reaction of the network to a dynamic stimulus, put a strong constraint on the computational capabilities of a neural network. We discuss the implications of our result for the spatial constraints imposed on the neural information processing.

The calculation of the laser absorption is very important for implosion simulations to capture precisely its dynamics. In many implosion simulations, the laser absorption is computed by the use of ray tracing. However, the conventional ray tracing method has the problem that it generates a non-physical absorption distribution because it represents a laser beam by a finite number of rays. Such a non-physical distribution on the target surface could be numerical perturbations that grow drastically due to Rayleigh-Taylor instability. An enormous number of rays are required to avoid such a non-physical distribution. This results in high computational costs. Thus, we have developed a new method of ray tracing that essentially generates no non-physical absorption distribution. In the new algorithm, rays are inversely traced from grid points unlike the conventional method. This paper presents the new algorithm and a preliminary implosion simulation where the pressure perturbation due to the non-uniformity of the irradiation is computed by the use of this new ray tracing.

Background: It is technically difficult to puncture deep-seated hepatic tumors by conventional laparoscopic ultrasonography with a linear-array probe. We have developed a laparoscopic ultrasonography system with a convex-array probe. Methods: The laparoscopic system used had a fixed forward-viewing convex-array transducer, and a guide groove for puncture was added to the back of the unit. These characteristics enabled us to continuously monitor the position of the needle tip on the ultrasonographic image immediately after puncturing on the liver surface. We attempted tumor puncture in 11 patients with hepatocellular carcinoma under a new probe guidance. Results: The mean puncturing distance up to the tumors was 38.7 mm. All punctures were successful on the first pass and the tumors were treated with radiofrequency ablation. Conclusion: Using this new equipment, puncturing hepatic tumors for treatment is relatively easy, irrespective of the position of the tumor.

It is demonstrated for the first time that photodarkening in colored filter glasses is associated with apparent growth of CdSxSe1−x microcrystallites. This is thought to be due to the attraction of impurity ions around the microcrystallites. Both a Q‐switched Nd3+:YAG laser and a hybrid mode‐locked dye laser are used as the light sources. Microcrystallite growth is directly observed by transmission electron microscopy and by field‐emission scanning electron microscopy. Growth is also inferred from local changes in color and measured absorption spectra.

The optical grating memory effect in polysilane film is investigated. A refractive index grating is formed within a few minutes by using visible light near room temperature. The grating formation time is dominated by the peak intensity of the pumping beams, and its dependence on the wavelength of the pumping beams corresponds to the two‐photon absorption spectrum. The grating formation mechanism is explained as the result of the chain scission induced by two‐photon absorption.

We have demonstrated an efficient second harmonic generation (SHG) using a mode-locked Nd:YAG laser and a pair of KTP crystals. The crystals are oriented in such a way leading to walk-off compensation and subsequently about four fold increment from the one of the pair in second harmonic output power. This is expected to open up various new potential applications.

Many studies have suggested an association between blood pressure (BP) and both insulinaemia and haematocrit values in Western populations. However, relatively few data regarding such associations for the Japanese population are available. We investigated the relationship between BP and various parameters, including insulin and haematocrit, in 269 healthy Japanese individuals (113 men and 156 women) over 60 years of age. The data were analysed by stepwise multiple regression analysis. In men, the most important determinant of systolic BP (SBP) and diastolic BP (DBP) was the plasma insulin concentration (beta = 0.32, F = 12.4, P < 0.001 and beta = 0.32, F = 13, P < 0.001, respectively), and haematocrit was found to be associated with DBP (beta = 0.21, F = 5.3, P < 0.05). In women, fasting insulins were unrelated to BP, but fasting plasma glucose and triglyceride concentrations and age were associated with SBP (beta = 0.29, F = 15.5, P < 0.001, beta = 0.27, F = 14.3, P < 0.001, and beta = 0.2, F = 7.8, P < 0.01, respectively), and haematocrit, fasting plasma glucose concentration and age were associated with DBP (beta = 0.29, F = 14, P < 0.001, beta = 0.2, F = 6.9, P < 0.01 and beta = 0.2, F = 6.3, P < 0.05, respectively). These results suggest that the insulin-BP associations in healthy Japanese subjects over 60 years of age differ according to sex, and that haematocrit is an important determinant of DBP in both sexes in our population.

In inertial confinement fusion, the implosion process is important in forming a high-density plasma core. In the case of a fast ignition scheme using a cone-guided target, the fuel target is imploded with a cone inserted. This scheme is advantageous for efficiently heating the imploded fuel core; however, asymmetric implosion is essentially inevitable. Moreover, the effect of cone position and opening angle on implosion also becomes critical. Focusing on these problems, the effect of the asymmetric implosion, the initial position, and the opening angle on the compression rate of the fuel is investigated using a three-dimensional pure hydrodynamic code.

In a fast ignition scheme using a cone-guided target, the fusion target is imploded with the inserted cone. Due to the existence of the cone, asymmetric implosion is not avoidable, which has the possibility to degrade fuel compression efficiency. This paper shows how the fuel compression and temperature at the maximum compression time are affected by changing the initial opening angle and position of the cone by the use of two and three dimensional fluid code.

A total of 83 specimens of surgically resected tumours from 78 patients with oesophageal cancer were assayed for drug sensitivity using an adhesive tumour cell culture system (LifeTrac CSA assay). Seventyone of 83 specimens had a sufficient number of cells to permit growth in culture and 57 of 71 (80%) were evaluable for drug response. Cells (3 x 10(3) ml-1 well-1) were cultured for 14 days and exposed to drugs on days 3-8. Growing cells were confirmed as cancer cells by immunohistochemical staining. IC90 values against several anti-cancer drugs were determined and population distributions of IC90 for each drug served as the basis for judging sensitivity. The 10th percentiles of IC90 (microgram ml-1) for CDDP, 5-FU, DOX, CPM, MTX, VP16, IFOS, VDS, BLM and CDDP + 5-FU were 0.3, 0.16, 0.005, 0.9, 0.006, 0.09, 0.8, 0.006, 0.04 and 0.15 + 0.09 respectively. The population distribution of IC90 against each drug showed a specific pattern that was very similar among histopathological gradings and stages of the disease. This system appeared to be a clinically applicable drug sensitivity test for human oesophageal cancer. Images Figure 1

We study the optical anisotropy and optical gain of (311) GaAs quantum-wire structures at room temperature. Quantum wires are directly formed during the growth of GaAs/AlAs multilayer structures by Molecular Beam Epitaxy due to the natural evolution of nanometer-scale corrugations on (311)-oriented GaAs and AlAs surfaces. The optical anisotropy evaluated in photoluminescence excitation spectroscopy reaches a value as high as 30% for the heavy-hole exciton resonance in 43A GaAs quantum-wire structures. The luminescence intensity of (311) GaAs quantum-wire structures is generally higher than that of conventional (100) GaAs quantum wells. In the regime of unsaturated optical gain, the amplified luminescence intensity of the quantum wires exceeds that of the reference quantum wells by fourfold.

This report clearly shows that the photodarkening effect in semiconductor-doped glasses comes from the color center formation of alkaline silicate glass. It also discusses the cause of response time shortening after darkening. It seems that fast and stable responses can be obtained with a specific alkaline metal composition, showing a change in the dielectric properties and also a drastic decrease in the ion conductivity based on the mixed-alkali effect. After-darkening phenomena, such as the absorption increase in all transparent region of the glass, the appearance of electron spin resonance (ESR) arising from the formation of glass color centers, and matrix glass changes observed with a field emission scanning electron microscope (FE-SEM), are distinctly shown.

All solid‐state cw passive mode locking of a Ti:sapphire laser is accomplished using a colored glass filter, instead of an organic dye, as a saturable absorber. The tuning range is remarkably wide (785–855 nm), and 2.7 ps pulses are obtained directly from the cavity.

The resistance evaluation of very narrow diffused layers is described. A two-dimensional analysis of the diffused layer conductance has been made using a numerical technique. A substantial reduction of the effective sheet resistance is shown to occur when the width of a diffusion mask window is narrowed relative to the junction depth. This indicates that the conductance of such narrow layers is influenced predominantly by the lateral diffusion effect, and that the geometrical effect of diffusion mask on the vertical impurity penetration can be almost neglected. The experimental data are in good agreement with this result. Design curves are presented to determine the resistance accurately, which are useful for the design of high-value resistors in integrated circuits.

Economy of integrated circuit fabrication in the presence of quasi-randomly distributed spot defects is described. The distribution of the defects is represented in terms of density and modeled as follows : 1) they are randomly distributed within a limited area; 2) the density in a wafer changes concentrically; and 3) the density is normally distributed from wafer to wafer with uniform deviation throughout a wafer. The yield degradation phenomenon due to such defects has been analyzed using a computer simulation technique. The effect of density variations in a wafer and between wafers has been mainly investigated. An extensive numerical study leads to the following conclusions. 1) The deviation of the yield versus chip-area relation from the simple exponential law is influenced more greatly by the nonuniform defect distribution in a wafer than by the density variation between wafers. 2) The increase of average yield due to the density variation between wafers is sometimes offset by the decrease of the accuracy in yield prediction. Process stabilization is essential for the economical production of a few large-scale chips.

As the structural and functional complexities in integrated circuits increase, yield prediction becomes as important as the calculation of electrical characteristics. This paper analyzes the yield loss resulting from the presence of the epitaxial mound, a material defect found very frequently on the epitaxial surface. The peculiarity of this yield-loss mechanism, especially in a contact printing system, is that not only does it act as a crystallographic imperfection but its damage accumulates on the emulsion or chromium photomask and thus propagates to other slices. Statistical investigations on its behavior have shown that the latter effect can be more detrimental than the former in large scale integration. These results are summarized in a simple mathematical expression that is used for yield prediction. Using the model, the damage by the epitaxial mound has been shown to be reduced by an improvement in photoetching process management, though the ideal solution lies in the reduction of the mound itself or in the use of a noncontact printing system.

NH3 absorption lines due to vibration‐rotation transitions are observed at 1.50–1.54 μm by using an InGaAsP superluminescent diode. A 1.5‐μm InGaAsP distributed feedback (DFB) laser is frequency stabilized to an NH3 linear absorption line at 15196 A. Frequency stability of σ(2,τ)=8×10−11τ−1 is achieved for an averaging time range of 10 ms≤τ≤1 s. Such an absolute frequency‐stabilized DFB laser is useful for coherent optical system applications, since it is free from the longitudinal mode jumping which results from a wide range of temperature changes and long‐term device degradation.

The CdSxSe1−x microcrystallites contained in colored filter glasses have been considered to be spherical. This letter demonstrates that in fact they are hexagonal columns, implying a wurtzite structure. Microcrystallite grain growth is observed in real time using an electron beam annealing method. Each grain is confirmed by energy dispersive spectrometry to be CdSxSe1−x. The grain size difference produces different optical transmission spectra due to quantum size effects. On the optical transmission spectrum of a sample with grains of 30 A, a new absorption band appears. This band can be explained by size quantization of the valence band.

The oscillation frequency of a 1.5‐μm InGaAsP distributed feedback laser is stabilized to an NH3 linear absorption line at 15137 A. A LiNbO3 external frequency modulator is used instead of direct frequency modulation of the laser to extract error signals. An effective bandwidth of 100 kHz for the feedback loop is obtained through this external modulation scheme. Frequency stability of σ(2,τ)=4×10−11 is achieved for an averaging time of 1 s≤τ≤100 s.

A PNP silicon UHF transistor using antimony as a base-dopant has been developed. A transit time frequency (fT) of the PNP transistor is inherently lower than the NPN transistor due to a larger base transit time. In order to increase the f T of the PHP transistor, the base layer structure has been designed so that the base transit time might occupy a smaller part in the total transit time.

BACKGROUND: Head injury increases the body's metabolic responses, and therefore nutritional demands. Provision of an adequate supply of nutrients is associated with improved outcome. The best route for administering nutrition (parenterally (TPN) or enterally (EN)), and the best timing of administration (for example, early versus late) of nutrients needs to be established. OBJECTIVES: To quantify the effect on mortality and morbidity of alternative strategies of providing nutritional support following head injury. SEARCH METHODS: Trials were identified by computerised searches of the Cochrane Injuries Group specialised register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, National Research Register, Web of Science and other electronic trials registers. Reference lists of trials and review articles were checked. The searches were last updated in July 2006. SELECTION CRITERIA: Randomised controlled trials of timing or route of nutritional support following acute traumatic brain injury. DATA COLLECTION AND ANALYSIS: Two authors independently abstracted data and assessed trial quality. Information was collected on death, disability, and incidence of infection. If trial quality was unclear, or if there were missing outcome data, trialists were contacted in an attempt to get further information. MAIN RESULTS: A total of 11 trials were included. Seven trials addressed the timing of support (early versus delayed), data on mortality were obtained for all seven trials (284 participants). The relative risk (RR) for death with early nutritional support was 0.67 (95% CI 0.41 to 1.07). Data on disability were available for three trials. The RR for death or disability at the end of follow‐up was 0.75 (95% CI 0.50 to 1.11). Seven trials compared parenteral versus enteral nutrition. Because early support often involves parenteral nutrition, three of the trials are also included in the previous analyses. Five trials (207 participants) reported mortality. The RR for mortality at the end of follow‐up period was 0.66 (0.41 to 1.07). Two trials provided data on death and disability. The RR was 0.69 (95% Cl 0.40 to 1.19). One trial compared gastric versus jejunal enteral nutrition, there were no deaths and the RR was not estimable. AUTHORS' CONCLUSIONS: This review suggests that early feeding may be associated with a trend towards better outcomes in terms of survival and disability. Further trials are required. These trials should report not only nutritional outcomes but also the effect on death and disability.