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To mitigate the susceptibility inhomogeneity induced by radio-frequency transmit phase error through the whole brain in quantitative susceptibility mapping (QSM) using single-echo gradient echo sequence, we developed a novel single-step QSM reconstruction algorithm and compared it with a previous algorithm in five healthy volunteers. The proposed algorithm had effectively suppressed the susceptibility inhomogeneity through the whole brain and achieved acceptable quality, similar to that of the susceptibility map calculated from a multi-echo gradient echo sequence.

INTRODUCTION AND OBJECTIVE:Renal puncture in endoscopic combined intrarenal surgery (ECIRS) greatly affects success rates and perioperative complications. We developed a method to determine the ide...

Streptococcus suis is an important zoonotic pathogen in swine and humans that causes sepsis and meningitis. Our previous study in Thailand showed that the prevalence of S. suis infection in humans, especially in northern areas of Thailand, and the transmission of the pathogen occurred mainly through the consumption of traditional raw pork products. Considering the high incidence proportion and mortality rate of the disease as an important public health problem, we implemented a food safety campaign in the Phayao Province in northern Thailand in 2011. We evaluated the effects of a food safety campaign by comparing the sociodemographic, clinical, and bacteriological characteristics of cases before and after the campaign. The follow-up study showed a marked decrease of the incidence proportion in the first 2 years, indicating the effectiveness of the campaign. In the third year, however, the incidence proportion slightly increased again, indicating the existence of deep-rooted cultural behaviors and the necessity of continuous public health intervention. Furthermore, epidemiological analysis of the cases made it possible to estimate the infectivity of the pathogen via the oral route of infection. In the present study, we showed the effectiveness of the food safety campaign for controlling the S. suis infection, and we present a role model public health intervention for prevalent areas affected by S. suis infection in humans.

INTRODUCTION AND OBJECTIVES:Partial nephrectomy for endophytic tumor is not only difficult to identify the tumor site but also the risk of positivity surgical margin and prolongation of warm ischem...

MR-only simulations provide pseudo-CT images which are segmented into 5 kinds of tissues from DIXON-based images. However, it is difficult to register pseudo-CT images to cone-beam CT (CBCT) images collected for image-guided radiation therapy (IGRT), because of the lack of contrasts among tissues. We validated gaps of IGRT between pseudo-CT or planning CT and CBCT for patients without implanted markers. We also propose calcification-assisted registration for MR-only simulation. We conducted retrospective analyses to verify the registration accuracy in 15 patients who underwent volumetric modulated arc therapy (VMAT) for prostate cancer. They underwent planning CT and pseudo-CT. Pseudo-CT images after deformable image registration (DIR) to planning CT images were rendered automatic pelvic bone matching to CBCT images. Patient positions on the pseudo-CT images after DIR were shifted on the basis of tissues around the prostate. We compared registration gaps between the images of planning CT and pseudo-CT with DIR, assuming that the tissue-based matching between the planning CT and CBCT was the gold standard. To the pseudo-CT images with DIR, calcifications detected on planning CT were added. We validated IGRT accuracy for a calcification-assisted registration. The absolute registration errors of the pseudo-CT, in comparison with the planning CT, were 0.34 ± 0.50 (lateral), 1.3 ± 1.3 (longitudinal), and 1.1 ± 1.0 mm (vertical). The absolute registration errors of the pseudo-CT with calcification contouring, in comparison with the planning CT, were 0.41 ± 1.0 (lateral), 0.87 ± 0.92 (longitudinal), and 0.74 ± 0.64 mm (vertical). Reduced absolute registration errors were observed in the proposed approach in the longitudinal (P

The two-level normal hierarchical model has played an important role in statistical theory and applications. In this paper, we first introduce a general adjusted maximum likelihood method for estimating the unknown variance component of the model and the associated empirical best linear unbiased predictor of the random effects. We then discuss a new idea for selecting prior for the hyperparameters. The prior, called a multi-goal prior, produces Bayesian solutions for hyperparmeters and random effects that match (in the higher order asymptotic sense) the corresponding classical solution in linear mixed model with respect to several properties. Moreover, we establish for the first time an analytical equivalence of the posterior variances under the proposed multi-goal prior and the corresponding parametric bootstrap second-order mean squared error estimates in the context of a random effects model., 21 pages,2 figures

症例は60歳女性，粘血便を主訴に大腸内視鏡検査，注腸造影検査を施行したところ上部直腸-直腸S状部(Ra-Rs）に1型腫瘍を認め，肛門管にかかる下部直腸(Rb-P）に2型腫瘍を認めた．生検結果はともに扁平上皮癌であった．以上よりRb-Pの約2cmの2型腫瘍，Ra-Rsの約6cmの1型腫瘍に対し，平成17年8月腹会陰式直腸切断術を施行した．病理検査結果ではRb-P腫瘍は低分化型扁平上皮癌，mp, ly2, v2であった．Ra病変は主座が粘膜下にあり，粘膜面には陰窩が残存して比較的保たれていること，これら組織が類似していることから下部直腸扁平上皮癌の上部直腸への壁内転移と判断した．われわれは下部直腸扁平上皮癌が上部直腸に同時性壁内転移をきたし，切除しえた稀な症例を経験したので報告する．

Recently, the space development project and the development of the hypersonic aircraft become more active in the world. In Japan the development facilities which compare favorably with the aerospace developing countries are needed.

Orientation effect on AlGaN/GaN heterojunction field-effect transistors (HFETs) has been experimentally and theoretically examined in detail. The drain-currents of the fabricated AlGaN/GaN HFETs with various gate directions do not depend on the gate orientation, whereas those of GaAs-based HFETs strongly depend on the gate direction due to the piezoelectric charges induced around the gate electrode. The piezoelectric charges induced in the vicinity of the gate electrode are simulated by using a finite-element method. This simulation solves the piezoelectric equations with piezoelectric and elastic stiffness constants, assuming that stress is applied to the gate edges in the HFET. The detailed simulation reveals that the piezoelectric charge distribution does not depend on the gate direction, although a large amount of piezoelectric charges is induced in the vicinity of the gate edges, which is consistent with the experimental result. Moreover, it is mathematically clarified that these experimental and simulated results are due to the symmetry characteristic of the piezoelectric and elastic stiffness constants for nitride semiconductor materials

Summary Background Although there have been several reports on the prevalence of atopic dermatitis (AD) in Japanese schoolchildren based on questionnaires, there has been no nation-wide study of the frequency of this condition diagnosed by dermatologists in regular health check-ups of schoolchildren. Objectives The objective of this work was to evaluate precisely the prevalence of AD in elementary schoolchildren in Japan based on regular health check-ups by dermatologists. Methods In 2001/2, elementary schoolchildren: first graders (age 6–7 years) and sixth graders (age 11–12 years) were examined by dermatologists in eight prefectures of Japan (Hokkaido, Iwate, Tokyo, Gifu, Osaka, Hiroshima, Kochi and Fukuoka). In each prefecture, public elementary schools were randomly selected from urban and rural districts. We planned to examine about 700 schoolchildren in each of urban first, urban sixth, rural first and rural sixth grades from the eight areas, a total of 22 400 children (700 × 4 × 8). AD was diagnosed by the dermatologists based on the Japanese Dermatological Association criteria for the disease. Results The point prevalence of AD was 11·2% overall (2664 of 23 719) ranging from 7·4% (Iwate) to 15·0% (Fukuoka) in the eight areas. Seventy-four per cent, 24%, 1·6% and 0·3% of those afflicted were in the mild, moderate, severe and very severe groups, respectively. Overall, the prevalence of first graders was slightly higher than that of sixth graders (11·8% vs. 10·5%, P

Almost fully relaxed thin SiGe buffer layers are obtained by Ar ion implantation into Si substrates before SiGe molecular beam epitaxy (MBE) growth. The strain relaxation ratio of the 100 nm thick Si0.65Ge0.35 layer grown on ion implanted Si substrate is about 95%, while it is only 60% in the unimplanted case. Surface morphology of the buffer layer on the implanted Si is very different from that of the conventional buffer, suggesting that a new strain relaxation mechanism takes place in the SiGe film grown on the ion implanted Si.

The purpose of this study is to report some knowledge gained from experiments in which we tried tooth bleaching using laser and bleaching agents on pulpless tooth due to trauma. We conducted in vitro experiments using extracted teeth of lower permanent central incisors with the following four conditions: (1) using 30% hydrogen peroxide (H2O2) and Nd:YAG laser, without Indian ink; (2) in addition to the condition of (1), with Indian ink; (3) using laser in conjunction with H2O2 and sodium perborate, without Indian ink; (4) in addition to the conditions of (3), with Indian ink. The bleaching agents that used 30% H2O2 and sodium perborate had more bleaching effects than the one with 30% H2O2 only. Furthermore, translucency was not lost in the cases in which Indian ink was not used. Obtaining above results, we conducted clinical trials under condition (3). In three trial cases, changes in shade were observed after the bleaching treatment. Largely satisfactory results were gained with over three times radiation in two clinical cases. After the bleaching treatment, the patients had no perceptive or apparent symptoms. Little recurrence of discoloration was found.

Strain-relaxed SiGe buffer layers (SiGe virtual substrates) are of great importance for fabricating such strained SiGe high-speed hetero-devices as strained Si channel MOSFETs. To obtain full relaxation of the SiGe films grown on Si substrates by the conventional graded buffer method, however, the thickness of the SiGe films generally has to be beyond several hundred nm. To overcome this problem, a low temperature (LT) method, where defects in the LT Si buffer layer act as dislocation sources and enhance the relaxation of the overgrown SiGe film, was invented. Here we propose a new method to introduce defects in Si substrates by ion implantation, which enhances the relaxation of SiGe films during growth of the SiGe films on ion implanted Si substrates. This ion implantation method may be superior to the LT method because its controllability of defects is much higher than that of LT method and it is applicable to the CVD method in which the LT growth cannot be performed.

Strained Si and Ge channel high-speed devices are generally formed on strain-relaxed SiGe buffer layers (SiGe virtual substrates). However, strain-relaxed SiGe buffers grown on Si substrates usually have rough surfaces and induce the interface roughness in the strained channel layers grown on the SiGe buffers, which is thought to reduce the mobility of the carriers in the channels. To overcome this problem, surface planarization of SiGe buffers by Chemical Mechanical Polishing (CMP) is sometimes performed. Here we investigated the strain field of the CMP planarized buffers and overgrown strained Si layers by micro Raman spectroscopy and electric properties of the overgrown modulation doped (MOD) structures.

We fabricated micro-tubes containing two GaAs/AlGaAs quantum wells (QWs) in a section of the tube layer, and studied the optical properties of the embedded QWs. A multilayer structure composed of GaAs and AlGaAs layers and a lattice-mismatched InGaAs layer was epitaxially grown on a GaAs substrate by MBE. This multilayer structure rolled up by the built-in strain when it was freed from the substrate. By measuring the photoluminescence peak shift of the QWs caused by the uniaxial strain, we were able to determine the radial profile of the strain within the micro-tube wall.

Colorless and crack-free single crystals of bismuth silicate (Bi4Si3O12, BSO) scintillators have been grown by the vertical Bridgman method. Some segregation phases have been found to form on the surface and at the top of the crystals grown from both stoichiometric and off-stoichiometric melt compositions. The excitation and emission spectra are similar to BGO. The light output is 20% of BGO, giving energy resolution of 32% for 662 keV γ-rays (137Cs). The decay constants are 2.4 ns (for 6% of intensity), 26 ns (12%) and 99 ns (82%). The radiation hardness against 60Co γ-rays was found about 105–106 rad at the emission peak of 480 nm for undoped and it was almost negligible up to 107 rad for 0.2 at.% Ce doped crystals. We have also achieved a considerable improvement in the growth of large size crystals, offering the possible application in γ-ray detectors at high energies. Clear blocks with transverse/longitudinal dimensions as large as 25 mm/200 mm were produced with good reproducibility. The pulse height uniformity along the longitudinal axis is within ±2%. The scintillation characteristics are similar to those of small crystals.

Background EUS-guided FNA (EUS-FNA) has become the most efficacious way to obtain specimens from a solid lesion adjacent to the GI tract. Previous reports regarding the use of a stylet during EUS-FNA were all based on cytological diagnosis and have showed no significant superiority in terms of diagnostic yield. Objective To clarify the noninferiority of EUS-FNA without a stylet (S−) compared with EUS-FNA with a stylet (S+) on histological assessment. Design A prospective, single-blind, randomized, controlled crossover study. Setting Five tertiary referral centers in Japan. Patients Patients referred for EUS-FNA of a solid lesion. Intervention EUS-FNA S+ and S− in a total of 4 alternate passes with randomization to S+ first or S− first. Main Outcome Measurements The primary endpoint was the acquisition rate of an appropriate and sufficient specimen for histological assessment. The secondary endpoints were cellularity, contamination, bloodiness, diagnostic ability, and diagnostic accuracy. Results We enrolled 107 patients (110 lesions) and analyzed 220 specimens each in the S+ and S− groups. The acquisition rate of appropriate and sufficient specimens in the S+ group was 121 of 220 (55.0%) and 122 of 220 (55.5%) in the S− group. The difference in the acquisition rate of the specimen (S− minus S+) based on the generalized estimating equation was 0.42% (95% confidence interval, −6.72% to 7.56%), which was less than 10% of the prespecified noninferiority margin of this study. With regard to cellularity, contamination, bloodiness score, diagnostic ability, and diagnostic accuracy, there were no significant differences between both groups. There were no dropouts in the study. Limitations A variety of target lesions, multiple pathologists, lack of an assessment of intraobserver and interobserver variability, and a single-blind study for the pathologists. Conclusion EUS-FNA S− is noninferior to EUS-FNA S+ on histological assessment. (Clinical trial registration number: UMIN000008695.)

Studies on low cost manufacturing processes for composite outer wing of SST (Super Sonic Transport) have been undertaken since 1998. This paper presents the study plan and results of the first two years. An integral skin/stringer panel made of Gr/Bmi(Graphite/Bismaleimide) is set for structural concept. For automated fabrication of structural details, a FPM (Fiber-Placement Machine) is constructed and suitable lay-up conditions are established. To minimize distortions of a large sized composite panel, distortion sources are listed. Curing tests of simplified elements are conducted for evaluations of distortion sources. For the first step of assembly automation, an auto drilling device is constructed and evaluated.

The aim of this study was to investigate prognostic factors and the most appropriate treatment for patients with ruptured middle cerebral artery (MCA) aneurysms in relation to haematoma distribution. Ninety-two patients with ruptured MCA aneurysms, who underwent surgery during the last 11 years from 1986 to 1996, were assigned to one of the three groups according to the haematoma distribution. Group A comprised 17 patients who had an intraparenchymal haematoma (IPH) larger than 30 mm (maximum diameter) with or without subarachnoid haemorrhage (SAH), group B comprised 24 patients having a dense intra-Sylvian fissure haematoma (ISH) larger than 30 mm (maximum diameter) and group C consisted of 52 patients having only diffuse SAH without a localized dense haematoma. The clinical course and factors affecting the outcome of the patients in each group were investigated. Patients in groups A and B had a more severe clinical grade on admission than those in group C. As a result, patients in these two groups had a poorer outcome. In group C, independent life was achieved for 98% of the patients. In group A, the clinical grade on admission and the diameter of the haematoma were significantly correlated with outcome. Initial brain damage due to IPHs seemed to be the main cause of disability, while only 7% developed delayed ischaemic neurological deficits (DIND). In group B, 54% of patients suffered from subsequent brain oedema and DIND occurred in 50%. These factors were related to a poor outcome. The MCA aneurysms tend to have localized dense haematomas, as well as diffuse SAH; the former seems to affect more on the course and outcome of the patients. Accurate assessment of the bleeding patterns in patients with ruptured MCA aneurysms will be useful in helping us predict the clinical course and the most appropriate treatment for these individuals.

Background EUS-guided FNA (EUS-FNA) has a high diagnostic accuracy for pancreatic diseases. However, although most reports have typically focused on cytology, histological tissue quality has rarely been investigated. The effectiveness of EUS-FNA combined with high negative pressure (HNP) suction was recently indicated for tissue acquisition, but has not thus far been tested in a prospective, randomized clinical trial. Objective To evaluate the adequacy of EUS-FNA with HNP for the histological diagnosis of pancreatic lesions by using 25-gauge needles. Design Prospective, single-blind, randomized, controlled crossover trial. Setting Seven tertiary referral centers. Patients Patients referred for EUS-FNA of pancreatic solid lesions. From July 2011 to April 2012, 90 patients underwent EUS-FNA of pancreatic solid masses by using normal negative pressure (NNP) and HNP with 2 respective passes. The order of the passes was randomized, and the sample adequacy, quality, and histology were evaluated by a single expert pathologist. Intervention EUS-FNA by using NNP and HNP. Main Outcome Measurements The adequacy of tissue acquisition and the accuracy of histological diagnoses made by using the EUS-FNA technique with HNP. Results We found that 72.2% (65/90) and 90% (81/90) of the specimens obtained using NNP and HNP, respectively, were adequate for histological diagnosis ( P = .0003, McNemar test). For 73.3% (66/90) and 82.2% (74/90) of the specimens obtained by using NNP and HNP, respectively, an accurate diagnosis was achieved ( P = .06, McNemar test). Pancreatitis developed in 1 patient after this procedure, which subsided with conservative therapy. Limitations This was a single-blinded, crossover study. Conclusion Biopsy procedures that combine the EUS-FNA with HNP techniques are superior to EUS-FNA with NNP procedures for tissue acquisition. (Clinical trial registration number: UMIN000005939.)

Twenty male volunteers, average age 24 years, participated in this study. Specimens were obtained by enamel biopsy using 5 microliters of 0.5 M HClO4 for 30 s. Using a regression curve, comparisons of fluoride concentrations were made at different depths. The fluoride concentrations (mean +/- SE) at a depth of 5 microns were highest in the distobuccal (1698 +/- 136), high in the mesiobuccal (1343 +/- 122), low in the distolingual (1119 +/- 107), and lowest in the mesiolingual sites (819 +/- 78). Of the interior enamels (or = 10 microns in depth), the distobuccal site (1330 +/- 88 parts/10(6) F at 10 microns) had a higher-concentration than all other sites. The fluoride profiles were steepest to shallowest in the order: distobuccal, mesiobuccal, distolingual and mesiolingual. There were no correlations between the enamel fluoride concentrations and the fluoride concentration in parotid saliva. It was concluded that in vivo fluoride profiles of maxillary first molars reflect the wear of the tooth surface with age and the condition of dental plaque deposition, and, to some extent, the site-specific distribution of saliva between buccal and lingual surfaces.

Iomazenil is a specific ligand for central-type benzodiazepine receptors (BZR). In order to determine the clinical significance of the findings of 123I-iomazenil single photon emission tomography (SPET) in cerebrovascular disease (CVD), we compared the cerebral uptake of 123I-iomazenil with oxygen metabolism measured by positron emission tomography (PET). Depending on the severity of the haemodynamic and/or metabolic impairment based on our institutional criteria [a reduction of30.6 ml 100g-1 min-1 in cerebral blood flow (CBF) and an increase of0.52 in the oxygen extraction fraction (OEF)], the cortical areas were classified into four groups as follows: Group I, normal CBF and OEF; Group II, normal CBF and increased OEF; Group III, reduced CBF and normal OEF; Group IV, reduced CBF and increased OEF. Seven patients (mean age 65 +/- 7 years) with CVD underwent both PET and 123I-iomazenil SPET within 8 days. The ratios of the mean counts in 14 regions of interest in the cerebral cortices to those in the cerebellar cortices (R/C ratios) were compared with the cerebral metabolic rate of oxygen (CMRO2). The R/C ratios of Group IV were lower than those of Group I (P0.005). The R/C ratios correlated with CMRO2 in Group III (r = 0.577, P0.01) and in Group IV (r = 0.707, P0.005), but not in Groups I or II. These results suggests that reduced uptake in 123I-iomazenil SPET reflects oxidative hypometabolism causing neuronal damage in haemodynamically and metabolically impaired areas in patients with CVD. This information may be valuable when deciding therapeutic approaches.

The strained Si modulation-doped (MOD) structure formed on the strain-relaxed SiGe buffer layer planarized by chemical mechanical polishing (CMP) was found to show significant mobility enhancement. The enhancement reaches a factor of 6 at low temperatures. The backgate dependence as well as temperature dependence of the transport properties of the MOD structure were investigated, and it was suggested that CMP drastically reduced the roughness scattering and increased the mobility of two-dimensional electron gas in the strained Si.

We have developed a quick-scanning x-ray absorption fine structure (QXAFS) system and installed it at the recently constructed synchrotron radiation beamline BL33XU at the SPring-8. Rapid acquisition of high-quality QXAFS data was realized by combining a servo-motor-driven Si channel-cut monochromator with a tapered undulator. Two tandemly aligned monochromators with channel-cut Si(111) and Si(220) crystals covered energy ranges of 4.0-28.2 keV and 6.6-46.0 keV, respectively. The system allows the users to adjust instantly the energy ranges of scans, the starting angles of oscillations, and the frequencies. The channel-cut crystals are cooled with liquid nitrogen to enable them to withstand the high heat load from the undulator radiation. Deformation of the reflecting planes is reduced by clamping each crystal with two cooling blocks. Performance tests at the Cu K-edge demonstrated sufficiently high data quality for x-ray absorption near-edge structure and extended x-ray absorption fine-structure analyses with temporal resolutions of up to 10 and 25 ms, respectively.

Using a 300 mm-wide monochromatic X-ray beam obtained at beamline BL20B2 of SPring-8, the difference in surface-strain distribution caused by various steps of silicon-wafer manufacturing, i.e. slicing, lapping, etching, grinding and polishing, was studied. The asymmetric 511 reflection of 21.45 keV X-rays, incident at a glancing angle of 0.26°, was used to obtain topographs over the whole surface of a 200 mm-diameter (100) CZ silicon wafer. Differences in crystallinity and in warp between the surfaces at different steps of the manufacturing process (firstly after the lapping following the slicing, and then after successive etching, grinding and polishing) were clearly observed. The former gave a topographic image over the whole area with a one-shot exposure because of their wide rocking curves (50–70 arcsec FWHM), which indicate poor crystallinity. The latter, on the other hand, showed sharper curves (4–5 arcsec FWHM), which indicate good crystallinity in local areas, and the existence of warp, and therefore required step scanning of ω-rotation to cover the whole surface in topography measurements. The effect of each step in the process is also discussed.

In small-field irradiation, the back-scattered radiation (BSR) affects the counts measured with a beam monitor chamber (BMC). In general, the effect of the BSR depends on the opened-jaw size. The effect is significantly large in small-field irradiation. Our purpose in this study was to predict the effect of BSR on LINAC output accurately with an improved target-current-pulse (TCP) technique. The pulse signals were measured with a system consisting of a personal computer and a digitizer. The pulse signals were analyzed with in-house software. The measured parameters were the number of pulses, the change in the waveform and the integrated signal values of the TCPs. The TCPs were measured for various field sizes with four linear accelerators. For comparison, Yu’s method in which a universal counter was used was re-examined. The results showed that the variance of the measurements by the new method was reduced to approximately 1/10 of the variance by the previous method. There was no significant variation in the number of pulses due to a change in the field size in the Varian Clinac series. However, a change in the integrated signal value was observed. This tendency was different from the result of other investigations in the past. Our prediction method is able to define the cutoff voltage for the TCP acquired by digitizer. This functionality provides the capability of clearly classifying TCPs into signals and noise. In conclusion, our TCP analysis method can predict the effect of BSR on the BMC even for small-field irradiations.

Prolonged monotonous driving may lower a driver's awareness level as well as increasing their stress level due to the compulsion to maintain safe driving, which may result in an increased risk of a traffic accident. There is therefore an opportunity for technological assessment of driver physiological status to be applied in-car, hopefully reducing the incidence of potentially dangerous situations. As part of our long-term aim to develop such a system, we describe here the investigation of differential skin temperature measurement as a possible marker of a driver's stress level. In this study, healthy male (n=18) & female (n=7) subjects were investigated under environment-controlled conditions, whilst being subjected to simulated monotonous travel at constant speed on a test-course. We acquired physiological variables, including facial skin temperature which consists of truncal and peripheral skin temperatures (T s ) using thermography, beat-by-beat blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR), and normalized pulse volume (NPV) used as an indicator of local peripheral vascular tone. We then investigated the driver's reactivity in terms of skin temperatures with this background of cardiovascular haemodynamics. We found that the simulated monotonous driving produced a gradual drop in peripheral T s following the driving stress, which, through interpretation of the TPR and NPV recordings, could be explained by peripheral sympathetic activation. On the other hand, the truncal T s was not influenced by the stress. These findings lead us to suggest that truncal-peripheral differential T s could be used as a possible index indicative of the driver's stress.

We demonstrate up-converted light emission from an asymmetric double quantum well (QW). Carriers in the wide QW, which are photogenerated by a long wavelength light, are transferred and collected into the adjacent narrow quantum well by using /spl Gamma/-X-/spl Gamma/ electron transfer and simultaneous hole tunneling, thus generating short wavelength light emission.

A system has been developed to rapidly calculate images of parametric rate constants, without acquiring dynamic frame data for clinical positron emission tomography (PET). This method is based on the weighted-integration algorithms for the two- and three-compartment models, and hardware developments (real-time operation and a large cache memory system) in a PET scanner, Headtome-IV, which enables the acquisition of multiple sinograms with independent weight integration functions. Following the administration of the radiotracer, the scan is initiated to collect multiple time-weighted, integrated sinograms with three different weight functions. These sinograms are reconstructed and the images, with the arterial blood data, are inserted into the operational equations to provide parametric rate constant images. The implementation of this method has been checked in H/sub 2//sup 15/O and /sup 18/F-fluorophenylalanine (/sup 18/FPhe) studies based on a two-compartment model, and in a /sup 18/F-fluorodeoxyglucose (/sup 18/FDG) study based on the three-compartment model. A volunteer study, completed for each compound, yielded results consistent with those produced by existing nonlinear fitting methods. Thus, this system has been developed capable of generating rapidly quantitative, physiological images, without dynamic data acquisition, which will be of great advantage to PET in the clinical environment. This system would also be of great advantage in the new generation high-resolution PET tomography, which acquire data in a 3-D, septaless mode. >

The most promising applications of IPv6 networks might be to embed any network structure, logically, inside its vast addressing space. We show here some useful examples of such applications as a basic multimedia application of H.323 video conferencing, a method of phone number mapping, personal ID number mapping, machine ID number mapping all in the IPv6 address space, a method of multi-homing with IPv6 addressing, and that of IPv4 source address inclusion in IPv6 addresses. Some of the applications are implemented and evaluated.

In this study, the polar structure of a rigid /spl alpha/-helical polypeptide which is well known as a cholesteric liquid crystal polymer is investigated. The polypeptide has a large dipole moment along the helical axis by adding the dipole moment of peptide groups. On analogy of the copolyester, it is expected that the polypeptic form a cholesteric mesophase with polar structure.

We have developed a novel 0.15 /spl mu/m CMOS process for high performance and high reliability, consisting of mixing the CoSi/sub 2/-Si interface using Si/sup +/ implantation to form shallow junctions, nitrogen implantation into gate electrodes to improve the oxide reliability, and selective channel implantation using a gate-around mask to reduce the junction capacitance. By using these processes, the propagation delay time of 21 psec/stage was obtained for a 0.15 /spl mu/m CMOS ring oscillator at the allowable maximum supply voltage of 2.0 V limited by hot-carrier degradation. >

Recent improved of larger-scaled microwave devices at the field such as communication systems demand a high-performance wiring substrate which has high thermal conductivity and good high-frequency characteristics. Aluminum nitride (AlN) has been considered a hopeful candidate to meet these demands because of its high thermal conductivity, but it also has been considered inferior to aluminum oxide because of its high dielectric loss. In this report, we have developed a new composition of AIN to meet the above demands and also cleared the detail of high-frequency characteristics of dielectric constant and dielectric loss. Furthermore we have cleared conductor loss of Tungsten (W), which is used as pattern materials of co-fired and multilayered substrate.

We have developed a new type of package for planar lightwave circuit (PLC) devices. An AlN heater was incorporated into a package in order to miniaturize the overall package size and to improve its thermal properties. In this paper, we evaluate the thermal and mechanical properties of the package. We successfully fabricated a thin package (8.5 mm in thickness), which is as thin as the butterfly package used for laser diodes. We observed that the temperature uniformity within the temperature-controlled area on the surface of the AlN heater was within 1/spl deg/C, and that the temperature stability of the surface of the AlN heater was within 0.4/spl deg/C when the ambient temperature was varied between -10/spl deg/C and 70/spl deg/C. We also found that our AlN heater had very good reliability. Fluctuations in the resistance of the AlN heater were within 0.3% after holding at 85/spl deg/C and 85% RH for 5000 hours, with or without a bias current (1 A) at the heater. Furthermore, this package had high durability against mechanical vibration, mechanical shock and thermal shock.

The Internet has changed society, enterprises and life style rapidly, and ushered in a new era of industrial revolution. We anticipated this trend and launched our new business strategy - "Everything on the Internet". This declaration means that Fujitsu focuses Internet from own business fields to management practice. We have three specific areas in which we wish to become a leader: 1) to be a provider of the Internet solution that merges platforms, information, electronic devices and services; 2) to establish and develop @nifty, Japan's largest Internet service provider - a user-friendly Internet environment to subscribers; and 3) to be the Internet user that implements management revolution by fully using our resources that the Internet can offers. Fujitsu group has leading edge technology and many proven solutions. In achieving this third target, we would like to play an active part as an IT company that focuses business, realizes speedy management, and has the competitive advantage combined with high growth and profitability.

Performance requirements are soaring for embedded processors, whose demand in multimedia processing is rising now more than ever. Some DSP and media processors satisfy this by means of VLIW architecture. However, for embedded processors, less code, low power and small die are compulsory. These requirements make 4-way super-scalar embedded processor impractical. This embedded processor utilizes 4-way VLIW architecture characterized by: (1) parallel execution by VLIW. (2) generic CPU function in combination with media processing function for enhancing multimedia processing ability. (3) NOP instruction suppressing by packing flags for compatibility among different parallel levels. (4) two parallel execution mechanisms, ILP and SIMD.

The chemistry and electronic properties of interfaces formed between thin films of the archetype molecular organic semiconductor 3, 4, 9, 10 perylenetetracarboxylic dianhydride (PTCDA) and reactive and nonreactive metals are investigated via synchrotron radiation photoemission spectroscopy. In, Al, Ti, and Sn react at room temperature with the anhydride group of the PTCDA molecule, producing heavily oxidized interface metal species and thick interfacial layers with a high density of states in the PTCDA band gap. The penetration of the reactive metal species in the PTCDA film is found to be inversely related to their first ionization energy. The noble metals Ag and Au form abrupt, unreacted interfaces. The chemical and structural results correlate well with the electrical properties of the interfaces that show Ohmic behavior with the reactive metal contacts and blocking characteristics with the noble metals. The Ohmic behavior of the reactive metal contacts is ascribed to carrier hopping and/or tunneling through the reaction-induced interface states. \textcopyright{} 1996 The American Physical Society.