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A numerical small signal noise analysis method for nonlinear circuits with a periodic large signal excitation, e.g. mixer circuits and switching circuits, is proposed. For small signal input responses, these nonlinear circuits are modeled as their linear periodic time-varying circuits. First, a numerical calculation method for the time-varying transfer function of a linear periodic time-varying circuit is described. Next, a noise analysis method is proposed for these circuits which contain noise sources modeled as cyclostationary random processes. Thermal noise and shot noise in the presence of periodic large signal excitation are modeled as cyclostationary random processes, each of which is modeled as a set of stationary random processes in continuous time. Aliasing components folded back to the baseband from high-frequency bands are calculated, and their powers are accumulated until their contributions become negligible. Simulated noise figures closely matched the measured values. >

C 36 H 18 cristallise dans P2 1 avec a=11.814, b=7.803, c=10.871A, β=91.41°, Z=2; affinement jusqu'a R=0.051. La molecule adopte une structure toit oblique, due a la presence de deux sites de recouvrement en forme de fjord, ce qui provoque une deformation vers une forme bateau du cycle central

The title compounds were synthesized and the structural aspects were examined by NMR spectroscopy.

IgE levels in faecal extracts (Copro-IgE levels) were investigated in food allergy (FA) patients before and after the challenge test administration of food allergens. IgE levels were measured by time-resolved fluoroimmunometric assay. In addition, the effects of administration of oral sodium cromoglycate (SCG) on the Copro-IgE levels were studied. Copro-IgE levels in patients with FA, who were placed on an elimination diet, did not differ from those of healthy children. After a challenge test immediate symptoms of urticaria and wheezing were observed in all FA patients. Copro-IgE levels in each patient increased markedly within 24 h of the challenge test. Moreover, FA patients treated orally with SCG showed neither the increase in Copro-IgE levels nor any remarkable symptoms after the challenge. Our results suggest that the increased Copro-IgE levels may be a specific consequence of the local immune response to food allergen stimulation in the gut mucosa.

For the elucidation of the mechanism of membrane stabilization by vitamin E, the effects of alpha-tocopherol and its model compounds on either retinol-induced hemolysis of rabbit erythrocytes or the permeability and fluidity of liposomal membranes have been studied. Retinol-induced rabbit erythrocyte hemolysis has been found not to be caused by the oxidative disruption of erythrocyte membrane lipids initiated by retinol oxidation, but rather to arise from physical damage of the membrane micelle induced by penetration of retinol molecules. In suppressing hemolysis, alpha-tocopherol was more effective than other naturally occurring tocopherols. alpha-Tocopheryl acetate, nicotinate, and 6-deoxy-alpha-tocopherol were more effective than alpha-tocopherol itself. The inhibitory effects of alpha-tocopherol model compounds having side chains with at least two isoprene units or a long straight chain instead of the isoprenoid side chain were similar to those of alpha-tocopherol. These data suggest that for protection of membranes against retinol-induced damage, the hydroxyl group of alpha-tocopherol is not critical, but rather the chroman ring, three methyl groups on the aromatic ring, and the long side chain are necessary. To verify the mechanism of the inhibitory effect on hemolysis, not only the effect of vitamin E and its model compounds on the membrane permeability and fluidity, but also the mobility of alpha-tocopherol molecule in membranes has been investigated using bilayer liposomes as the model membranes. Addition of alpha-tocopherol to membranes produced a greater decrease in the permeability and fluidity of rat liver phosphatidylcholine liposomes compared with egg yolk phosphatidylcholine liposomes. In dipalmitoylphosphatidylcholine liposomes, however, alpha-tocopherol was less effective, that is, the more unsaturated the lipids, the more they interact with alpha-tocopherol. 2,2,5,7,8-Pentamethyl-6-chromanol with no isoprenoid side chain and phytol without the chromanol moiety had no effect. The measurement of 13C NMR relaxation times revealed that the mobility of methyl groups on the aromatic ring of alpha-tocopherol in membranes is significantly restricted. In contrast, the methyl groups at positions 4'a and 8'a on the isoprenoid side chain have high degrees of motional freedom in the lipid core of membranes. Furthermore, it was found that alpha-tocopherol in membranes interacts with chromate ions added as potassium chromate outside the membranes, resulting in an increase in membrane fluidity. These results are compatible with those of the inhibitory effect on retinol-induced erythrocyte hemolysis. On the basis of the results obtained here, a possible mechanism for membrane stabilization by vitamin E is proposed.

The title compounds were synthesized and the structural aspects were examined by NMR spectroscopy.

Este trabalho consistiu na modelagem hidrológica de uma microbacia hidrográfica utilizando-se o modelo HidroBacia, no qual o processo de infiltração da água no solo é representado por meio da equação de Green-Ampt modificada por Mein e Larson. Obtiveram-se, dentre os parâmetros desta equação, o potencial matricial na frente de umedecimento, a condutividade hidráulica e a umidade do solo na zona de transmissão, através de diversos métodos apresentados na literatura; desta forma, foram preparadas e testadas 36 combinações de dados de entrada, visando identificar as que apresentam melhor desempenho nas simulações do hidrograma de escoamento superficial com o modelo e se selecionaram, dentre os eventos de chuva-vazão registrados na microbacia, os 14 mais relevantes para realização das simulações. Das 36 combinações de dados de entrada testadas, seis apresentaram melhor desempenho na estimação dos hidrogramas. O modelo HidroBacia ainda necessita de aprimoramentos, juntamente com análises de sensibilidade, com vista a identificar possíveis incompatibilidades entre os dados de entrada e os respectivos resultados das simulações, uma vez que o modelo apresentou resultados incoerentes em determinadas situações. This work consisted of the hydrologic modeling of a small watershed using the HidroBacia model. The soil water infiltration process is represented by means of the Green-Ampt equation, modified by Mein and Larson, in this model. Among the equation parameters, matric potential in the wetting front, hydraulic conductivity and soil moisture in the "field saturation" were obtained using different methods based on previous scientific literature. Thirty six input data combinations were tested in order to identify those that showed better performance on the runoff hydrograph simulations with the model. Between the rainfall-runoff events registered on watershed, the most relevant (14) of them were selected to perform the simulations. Six of 36 input data combinations tested showed better performance in the hydrograph estimations. The HidroBacia model still needs more improvenents, as well as sensitivity analysis in order to identify incompatibilities between input data and the simulation results, since the model showed incoherent results under certain situations.

This report describes our retrospective evaluation of CT features of the acute phase in 34 cases of ruptured cerebral aneurysms of the posterior cranial fossa. The results are as follows. 1. Examination of cisternal haematoma distribution revealed that SAH had extended to the supra- and infratentorial cisterns in 28 cases (82%). There were only 6 cases (18%) in which SAH was confined to the posterior cranial fossa only but even when there was subarachnoid haematoma in both the supra- and infratentorial cisterns, thick haematomas were seen at the periphery of the brain stem. In cases of vertebral artery-posterior inferior cerebellar artery aneurysms (VA-PICA AN), haematomas in the ambient cistern were thicker on the aneurysm side. In addition, in cases of basilar artery-bifurcation (BA-Bifurcation AN) and basilar artery-superior cerebelli artery aneurysms (BA-SCA AN), there were many thick, high-density haematomas in the interpeduncular cistern. 2. The rate of intracerebral haemorrhage was extremely low (1 patient). 3. The rate of intraventricular haemorrhage was high, and these haemorrhages demonstrated a reflux pattern. 4. The rate of hydrocephalus was high (76.5%) in comparison with that noted in association with SAH due to the rupture of anterior circulation aneurysms.

We report on de Haas-van Alphen (dHvA) effect measurements at ambient pressure and band-structure calculations for ${\text{LaRhSi}}_{3}$ and ${\text{CeRhSi}}_{3}$, whose crystal structures lack space-inversion symmetry. For ${\text{LaRhSi}}_{3}$, dHvA frequencies up to $\ensuremath{\sim}11\text{ }\text{kT}$ with effective masses up to $\ensuremath{\sim}1.6{m}_{e}$, where ${m}_{e}$ is the free-electron mass, are observed. The observed and the calculated Fermi surfaces are in satisfactory quantitative agreement. The energy splitting of bands due to the spin-orbit coupling is estimated to be of the order of ${10}^{2}\text{ }\text{K}$. For ${\text{CeRhSi}}_{3}$, dHvA frequencies up to $\ensuremath{\sim}12\text{ }\text{kT}$ with effective masses up to $\ensuremath{\sim}19{m}_{e}$ are observed. The dHvA frequency branches are definitely different from those observed in ${\text{LaRhSi}}_{3}$ and are difficult to explain with the ${\text{LaRhSi}}_{3}$ Fermi surface. This leads to the conclusion that the $\text{Ce}\text{ }4f$ electrons in ${\text{CeRhSi}}_{3}$ are itinerant in the antiferromagnetic state at ambient pressure. The Fermi surface resulting from a band-structure calculation in which the $\text{Ce}\text{ }4f$ electrons are treated as itinerant can provide a plausible explanation for the observed frequency branches, although the quantitative agreement is rather limited. The comparison of the calculated density of states with the Sommerfeld coefficient gives the mass enhancement factor of 8.

We investigated surgical complications and prognosis of bronchoplasty and bronchoplasty with pulmonary angioplasty (broncho-angioplasty) for lung cancer. Between October 2000 and October 2007, 37 bronchoplastic procedures were done in 572 patients who underwent lung resections for lung cancer. Eleven (29.7%) bronchoplasties were done with pulmonary angioplasty. There was no operative mortality and 1 hospital mortality (2.7%) causing by myocardial infarction. Six of 11 postoperative complications were bronchial complications and 2 additional lung resections were needed. The 5-year survival for all patients was 55.2% and for bronchoplasty was 57.8%. Though the 5-year survival of broncho-angioplasty was not able to calculate at present, the 3-year survival of which was 72.9%. There was no death of patients with adenocarcinoma after introduction of pre-operative assessment by FDG-PET for lymph node metastasis. These data suggest that bronchoplasty and broncho-angioplasty are safe operative procedures and could provide acceptable intermediate survivals with modern multimodality diagnostic and therapeutic tools.

In this study, we investigated T2 weighted imaging (T2WI) and T2 values of the cortex, thalamus and cerebrospinal fluid (CSF) of the ventricles in the canine double-haemorrhage subarachnoid haemorrhage (DHSAH) model. T2 values in the cortex increased compared to prescan values from 123.07 +/- 18.72 msec on day 2 to 89.43 +/- 1.98 msec on day 7 (p0.05). A trend toward a temporal increase in T2 values was observed in the thalamus, but did not reach significance. The T2 values of the ventricular CSF increased by 102.2% on day 2 and 159.6% on day 7 compared to prescan values. These changes reached significance (p0.05) on day 7. Additionally, the ventricular size increased over the study period. Our data suggest that we can use this model to investigate acute brain injury and normal pressure hydrocephalus (NPH) after SAH.

Thick target yields of α particles emitted in the 6Li(d,α)4He and 7Li(p,α)4He reactions were measured for Li target in the solid and liquid phase. Observed reaction rates for the liquid Li are always larger than those for the solid. This suggests that the stopping power of hydrogen ion in the liquid Li metal might be smaller than in the solid. Using the empirically obtained stopping power for the liquid Li, we have deduced the screening potentials of the Li+p and Li+d reactions in both phases. The deduced screening potential for the liquid Li is about 500 eV larger than for the solid. This difference is attributed to the effect of liquefied Li+ ions. It is concluded that the ionic screening is much stronger than the electronic screening in a low‐temperature dense plasmas.

Recent lower hybrid current drive (LHCD), and heating (LHH) experiments on JT-60 are reported. The current drive product of neRpIRF approximately 12.5*1019 m-2 MA was achieved at the LH power of approximately 4.5 MW, and the CD efficiency, the energy confinement, the global power balance and the heat load on divertor plates were investigated in high power LHCD plasmas. Nearly steady state H-mode discharges were found during LHCD with two different frequency injections. Sawtooth suppression in NB heated plasmas by LHCD have shown an improvement in confinement near the plasma center. Parametric instabilities in LH heating experiments were significantly reduced by increasing the plasma current, and the stored energy increased linearly with heating power of up to approximately 9 MW at ne approximately 7*1019 m-3 and Ip=2.75 MA. Parametric instabilities near the plasma edge in the ion heating regime were also reduced in peaked density plasmas produced by pellet injection and LH waves increased the central plasma pressure at ne(0) > 1.4*1020 m-3.

One of the excitations, 'carrier', is a large signal and an arbitrary T-periodic function of time. The other excitation, 'signal', is considered as a small perturbation to the periodic steady-state response driven by the carrier. To find a small signal frequency response for the 'signal', the method uses variational equations around the periodic steady-state response. These linearized time-varying differential equations are solved in the frequency domain using a time discretization method. The method can be used to compute the small signal frequency responses of nonideal switched capacitor filters, mixers, and other nonlinear circuits, if the circuit has a stable periodic response. The formulation of the problem, computational complexity of the method, error analysis, sensitivity analysis, implementation of the method, and some applications are covered. >

A model analysis of the second-harmonic electromagnetic wave generated by the Cherenkov effect in an optical channel waveguide made of an anisotropic dielectric is discussed. With the effective-refractive-index method the waveguide is modeled by two slab-type waveguides. Both TE and TM waves are considered, and the polarization dependence of the second-harmonic power is studied. Numerical results for the configuration giving maximum second-harmonic power are in close agreement with experimental results. >

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

This paper presents a dynamic reconfigurable architecture for a low-power despreader in VSF-OFCDM systems. Since the spreading factors in time and frequency domains are dependent of cell configurations, channel loads, and propagation channels, a circuit structure of the despreader is to be optimized according to these variable conditions. The proposed despreader, it is based on a dynamic reconfigurable architecture, offers optimum concurrent and pipeline processing and minimizes memory accesses using an adder network. The results show that the proposed despreader has reduced power by 13-60% compared with a basic despreader.

Aspirin prevents the production of thromboxane A2 (TXA2) by irreversibly inhibiting platelet cyclooxygenase, exhibiting antiplatelet actions. This agent has been reported to prevent relapse in patients with ischemic heart disease or cerebral infarction via this action mechanism. However, there are individual differences in this action, and aspirin is not effective in some patients, which is referred to as 'aspirin resistance'. In this study, we analyzed laboratory aspirin resistance by platelet aggregation in 110 healthy adult Japanese males using 24 single-nucleotide polymorphisms (SNPs) of nine genes involved in platelet aggregation/hemorrhage. Among SNPs involved in platelet aggregation, aspirin was less effective for 924T homozygote of a TXA2 receptor, 924T>C, and 1018C homozygote of a platelet membrane glycoprotein GPIbalpha, 1018C>T, suggesting that 924T and 1018C alleles are involved in aspirin resistance.

This paper presents a simulation framework for ubiquitous robot and sensors. For ubiquitous robot, the importance of a distributed sensor environment is emphasized. To simulate such an environment, the effect of environment sensor should be considered as well as a robot itself to verify the performance of the overall system. To remedy this problem, the integrated simulation framework is suggested. In the proposed scheme, each sensor and robot are implemented as RT components. This can be achieved using RT-middleware, which is developed by AIST. Using RT components, the interface module can be reused in real environment because the interface module will have common design between the simulation space and the real environment. This is one of merits of RT-Middleware. OpenHRP, which is considered as target platform, is also introduced.

A cluster-based server system is a developing technology that could achieve high scalability by using several dispatchers, such as layer-4 or layer-7 switches, to appropriately distribute requests from clients. Many recent Web server systems have been developed as cluster systems, but such systems are so complicated that important information for appropriate distribution decisions is in higher layer (i.e., application layer, or layer-7). Although the L7 switches are appliances that can redirect requests by examining the application-layer information, it is difficult to update or modify their distribution algorithms. This paper proposes a novel architecture based on TCP-migration mechanism that provides complete redirection (displacement) of a TCP session from a dispatcher to Web servers. The key idea is physical separation of L7 switch functionality: packet forwarding and request dispatching mechanisms. With NAT mechanism on the L3 switch and sophisticated management of virtual private IP addresses on the cluster servers, the dispatcher is released from relaying or translating both in-bound and out-bound TCP packets after the request has been redirected. This architecture can achieve greater flexibility because the forwarding is performed fast by hardware (i.e., the switch), and the dispatching is managed by software (i.e., application servers). We have designed and implemented this mechanism on Linux 2.4 kernel and evaluated its performance. The experimental results show that the overhead for handling multiple virtual IP addresses is almost negligible. Furthermore, the overhead with TCP-migration by using mini_httpd server and wget client is approximately 1 ms, regardless of the reply size, on 3.06 GHz Xeon machines

The paper gives an overview of results achieved by a three-year project of the Japanese government on carbon nanotube field emission display (CNT-FED). The issues of the project are the development of uniform electron source and the development of glass panel technologies. Electron source development methods include, high-temperature CVD method, low-temperature CVD method, and printing method and activation technologies. In the case of glass panel technologies, main subjects include the development of basic panel structure and heat-resistant lead-free sealing material.

For this paper, the impact behaviors and the damage state of plain-woven CFRP reinforced by spread tow due to falling weight were evaluated. Stress-Strain responses of the CFRP using spread tows were investigated under drop-weight impact loading at room temperature. Three leveled impact energy was applied to the surface of the specimen in the drop-weight test. The peak load and absorbed energy were then compared with those of a conventional one and the experimental results showed that the peak load and absorbed energy of the developed CFRP were higher. A large amount of energy was absorbed due to the propagation of macro cracks and delaminations near the counter surface in the developed CFRP. When reinforced by spread tow its structure absorbs a large amount of energy after the initial stage of impact damage. The SAI (static strength after impact) and the FAI (fatigue life after impact) were also examined and the tensile test results showed that the static strength retention of the developed CFRP was higher than those of a conventional one. The developed CFRP also has long fatigue life under the tension-tension cyclic load after the impact. It was found that it maintained superior mechanical properties compared to the original, even after the material was damaged due to impact, because critical propagation of the debonding was prevented around the warp of thin cloth. This paper concludes that reinforcing with spread tow is effective for improving the mechanical properties of plain-woven CFRP during and after impact loading.

After segmentation of the epidermis from three-dimensional coherence tomography volume, a depth-oriented algorithm provides a segmentation of the infundibulum. In this process, the epidermal thickness, the population and the occupation ratio of the infundibula are provided.

This chapter discusses localized spin exchange coupled with itinerant electrons in organic π-electronic system. Itinerant electrons are known to play an important role in aligning electron spins in inorganic ferromagnets such as 3d metals or rare-earth metals. The spin alignment of localized spins of organic radicals through the spin-polarized Ti-conjugating electrons is elaborated in the chapter. A cautious examination of this spin-ordering mechanism leads to the creation of a new class of donor radicals, designated as spin-polarized donors. Pyrrole-type spin-polarized donor, in particular, produced a spin-polarized molecular wire with protected-thiol groups at both terminals. A combination of the spin-polarized wire and metallic gold nanoparticles gave birth to a coexistence system of itinerant electrons and organic localized spins. It was found that this networked gold nanoparticle connected by the spin-polarized molecular wire exhibited the negative magnetoresistance when an external magnetic field was applied. Such an organic and inorganic hybrid system may give insights into the spin-ordering problem in graphites and other carbon-based materials.

This paper describes the architecture and the evaluation results of a parallel computer Cenju-4. Cenju-4 supports two memory architectures: distributed memory with user-level message passing communication and distributed shared memory with cache-coherent nonuniform memory access (cc-NUMA) feature. Cenju-4 system consists of from 8 to 1024 nodes connected by a multistage network which has multicast, synchronization, and gather functions. Cenju-4 adopts a Mach micro kernel based operating system, which provides several services for parallel processing. We attained 5.5 psec communication latency and 168 Mbytes/sec communication throughput an message passing communication.

The areal density of magnetic disk is expected to grow to over 20Gb/in 2 by the end-1990s. In the INTERMAG'96, the authors demonstrated high areal density of 5Gbit/in 2 with PR4ML channel. The thermal instability can not be neglected at higher areal density than 5Gb/in 2 . It indicates the necessity to use the code which expand bit length such as (1,7) RLL code. We consider the best combination of (1,7) RLL code and a partial response channel. The partial response system of the polynomial (1+D)(1-D 2 ) called modified E 2 PR4(MEEPR4) exhibits the best performance. We performed this partial response simulation model with white noise and media - noise and examined the architectural consideration in the design of the experimental prototype.

We discuss several types of potential instabilities in nonlinear electronic circuits due to sub- and ultra-harmonics generation, as well as intermodulation distortions caused by either multi-frequency input signals or coupling between intrinsic oscillatory modes. The limitations of traditional approach used for the circuit analysis in the time domain, like, e.g., harmonic balance or small-signal analysis approximation, are elucidated, and the constructive method for avoiding an unexpected destabilization of operation and thus providing a way of stable circuits design is proposed. Analytic criteria for stability are derived for a particular class of passive circuits composed of several lumped elements that is described by systems of ordinary differential equations with two or more degrees of freedom. The general condition predicting the appearance of chaotic oscillations, as well as other instabilities, such as saddle-note (flip) and sub-harmonic (period-doubling) bifurcations in multi-mode systems is obtained by means of the largest Lyapunov exponent analysis

In this report, we propose a new architecture of a matched filter used in CDMA systems. The new architecture reduces the calculation cost of required data correlation significantly. Since the calculation of the correlation into a matched filter becomes quite large amount of operation, the large circuit scale and the high power consumption happen on a mobile system. Accordingly the low calculation cost has been demanded. The proposed matched filter applies two step correlation algorithm into the data processing. Therefore, the amount of the operation can be decreased. In addition, it is expected that the operation speed and the power consumption of a matched filter circuit module are improved.

In this paper, audio servo robot system which was a servo system using audio information as feedback signal was considered. Since the sampling rate of audio signal and that of robot controller are usually different, the system is able to be treated as a multi-rate system. Since it is general that the sampling rate of the output is faster than that of the input, the controller obtains more information than a single-rate servo system. By using this property, an adaptive audio servo system was proposed. Results of a computer simulation and an experiment showed effectiveness of the method.

The purpose of this research is to realize an absolute position control of mobile robot. Several researches with respect to position control of mobile robot considering its nonholonomic constraints have already reported. They are so powerful, but there are still some issues to improve the control performance. First, the disturbances such as wheel slip, modeling error, and so on deteriorate the position response. So the disturbances suppression should be considered. Second, it is difficult to predetermine the trajectory to reach the desired position because of the nonholonomic constraints. To improve the performance of the position convergence, it is strongly required to develop the trajectory generation algorithm independently of the nonholonomic constraints. In the proposed approach, the absolute position detected by PSD is used to construct the robust position controller. Furthermore, the virtual forces to swing the mobile robot and to modify its orientation are arbitrarily generated to guarantee the convergence to the desired position even if the position response is affected by slip motion or uneven floor. Several numerical and experimental results are shown to verify the validity of the proposed approach.

A method of frequency offset detection for signal interpolated timing recovery is proposed. The frequency offset is estimated by measuring the correlation between the preamble and the reference sinusoid. When the frequency offset exists, the phase error changes linearly. The offset can be estimated by the gradient of the phase errors. The simulation results show that the method significantly improves the stability of the timing recovery and increases the capture range. It also decreases the preamble length and results in higher format efficiency.

The two types of design methods for nonlinear control systems have been proposed. One is based on the analytical approach, where a nonlinear controller is constructed through the energy balancing (EB) passivity-based control, and the other is based on the numerical approach, where a nonlinear controller is numerically approximated through a virtual optimal control algorithm, Moreover, those two methods are demonstrated to be efficient in the nonlinear situation through the design problem of a jet engine compressor model.

We have reported a single lens with a numerical aperture (NA) of 0.85 at ISOM 2001. This report describes general principle for the determination of a start data in the single lens design. Applying the principle in the design, we also developed a new smaller lens.

The JT-60 JAERI (Japan Atomic Energy Research Institute) Tokamak-60 neutral beam injector (NBI) has been successfully operated for three years, delivering a neutral beam power of 20 MW at a beam energy of 75 keV. The helium-beam injection into JT-60 was performed to investigate exhaustion of fusion alpha particles from the plasma. The helium-ion beam current extracted from ion sources was 40-45 A at an energy of 31 keV. The injection power was about 0.4 MW. In the helium-beam operation, the helium gas in the beamline chamber was pumped out by a condensed SF/sub 6/ gas cryosorption pump. The JT-60 neutral beam injector will be modified to inject a 120-keV deuterium beam into the JT-60 upgrade, which will start to operate at the beginning of 1991. >

Autonomous mobile robots are required to be sensitive to changes of their surrounding environment for handling physical resources and supporting open and distributed human-robot-computer systems. But it is difficult to incorporate sensitivity into real-time systems, and to identify the owner of a physical resource in an open and distributed human-robot-computer system. In this paper, the authors present an operating system PULSER that supports sensitivity with real-time facility, and provides a physical resource manager that is based on the ownership model, the solution to the physical ownership problem. Also, they describe a new facility for wireless communications in open and distributed systems. >

The properties and physiological effects of plant cerebrosides were investigated. The major sphingoid bases of cerebrosides from soybean, maize, and rice bran were trans-4, cis or trans-8-sphingadienine. However, the major sphingoid bases in wheat and rye grains were 8-sphingenine mainly with the cis-configuration (more than 60%). The phase transition temperature of plant cerebrosides measured by differential scan calorimetric method was significant lower than that of bovine brain cerebroside. Plant cerebroside-derived compounds such as sphingoid bases induced apoptosis in human colon cancer cell lines. This result suggested that dietary plant cerebrosides have a potent physiological function similar to that of animal sphingolipids.

A noise-analysis method for nonlinear circuits with a periodic excitation, e.g. switched-capacitor networks (SCNs) and mixer circuits, is proposed. The nonlinear circuits are modeled by linear periodic time-varying circuits. An equivalent current source is connected in parallel with each noise source and its output noise is computed. Thermal noise and shot noise from linear and nonlinear elements can be computed. Aliasing components folded back to the baseband from high-frequency bands are calculated, and their powers are accumulated until their contributions become negligible. This algorithm has been implemented in the SPREAD circuit simulator. Three switched-capacitor networks and a mixer circuit were simulated. The simulation results closely matched the exact solution for a simple switched-capacitor circuit. Furthermore, they nearly matched with the measured values. >

Superlattice type photodiodes of a GaAs-Al/sub x/Ga/sub 1-x/As structure were studied at room temperature. A combination of potential-well width and barrier width was sensitive to the charge multiplication factor. Using a diode with a 10 nm well and a 15 nm barrier, the detector characteristics were investigated from a point of view of achieving a high gain. This type of photodiode was confirmed to be sensitive to Cherenkov light generated in water. Effects of carrier doping up to 10/sup 18/ cm/sup -3/ at room temperature on the multiplication rate is discussed.

This study was carried out to clarify the efficacy of magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of biliary tract diseases, Three hundred and eleven patients who underwent MRCP and ERCP during the period from January 1999 to December 1999 at our institution were included in the study. Two gastroenterologists who were blinded to results of direct cholangiography and final diagnoses interpreted MRCP images prospectively. The biliary duct was visualized by MRCP and ERCP in 99.4% and 89.5% of the cases, respectively. The sensitivity, specificity, and accuracy of MRCP in the diagnosis of choledocholithiasis were 95%, 97%, and 97%, respectively. MRCP depicted the presence of strictures with a sensitivity, specificity, and accuracy of 97%, 96%, and 96%, respectively. There were three false-positive cases because of artifacts from arterial compression, The accuracy of MRCP and ERCP in differentiation of benign strictures from malignant ones was 85% and 96%, respectively. Based on these results, it is concluded that MRCP has high capability in visualization of the biliary tree, and in detection of stones and strictures, To avoid over and under-diagnosis, awareness of some pitfalls inherent in, MRCP is important. We suggest that MRCP should be recommended for patients with suspicion of biliary tract diseases in the initial stage of making diagnosis.