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Critical state field profiles and thermomagnetic instabilities are studied in two kinds of three-dimensional nanostructured superconductors. We find that the critical state field profiles in some simple bi-layer systems are not simple superpositions of critical states in the two layers. Competition between the divergence of the local field at the edges of the film and the shielding by the neighboring layer makes novel critical state field profiles. We also studied flux avalanches in shifted strip arrays (SSAs) with layer numbers up to six. Various forms of avalanches either perpendicular or parallel to the strip are observed when the overlap between strips in neighboring layers is large. We also find that introduction of asymmetry in various forms to SSA affects the shape of flux avalanches sensitively.

We have fabricated multi-layer superconducting shifted strip arrays (SSAs) of Nb up to 4 layers and systematically studied the vortex penetrations into these structures. We observed the vortex penetration as a function of the number of layers and the ratio of overlap between neighboring layers by using magneto-optical (MO) imaging. In the case of 2- and 3-layer SSAs, spot-like avalanches occur when the overlap is small, while linear avalanches occur when the overlap is large, consistent with our previous reports. In the 4-layer SSAs, the smallest limit of the overlap between the neighboring layers for the linear avalanche is lower. Flux penetrations parallel to the strip which were observed in the 3-layer SSA were also observed in the 4-layer SSAs with smaller ratio of overlap. Larger demagnetization effects in the middle two layers in 4-layer SSA help to make avalanches larger and more extended.

Ultrasonic welding is one of the most common methods for joining thermoplastics. The two plastic parts to be joined are placed on the fixture before high frequency mechanical vibration is applied to the parts through an ultrasonic horn. This generates heat at the joint area and locally melts thermoplastics. The parts are welded together. In this paper, we investigate the effect of the contact area between the lower part and the fixture on the dynamic behaviour of the joint interface, which affects heat generation. The displacements and elastic strains of the interface are predicted using finite element dynamic contact analysis and compared for different contact areas. The results show that the dynamic behaviour of the interface depends on the dynamic characteristics of the two parts. When both natural frequencies are close to the horn vibration frequency, the displacements and strains are small. Conversely, when the lower part has no natural frequency near the horn vibration frequency, the displacements and strains are large. The contact area significantly affects the dynamic behaviour of the interface. This is because its dynamic behaviour depends on the natural frequencies of the parts to be joined while the natural frequency of the lower part is easily improved by the contact area.

A VTH mismatch self-repair scheme in 6T-SRAM with asymmetric pass gate transistor by post-process local electron injection is proposed. Local electron injection is automatically and simultaneously achieved to either pass gate transistor that most increases the read margin for each cell without investigating its characteristics. The proposed asymmetric VTH shift is twice as large as the conventional scheme without process and cell area penalty. Measurement results show 20% increase in SNM without write degradation by the asymmetric PG transistor. The proposed scheme also enhances the minimum read margin by 70% while reducing read margin distribution by 20%, thanks to the self-repair function.

We treated post-traumatic contracture of the elbow in 13 consecutive patients (14 elbows) by operative release. Through a single medial approach, the posterior oblique bundle of the medial collateral ligament was resected, followed by posterior and anterior capsulectomies. An additional lateral release through a separate incision was required in only four elbows. The results were assessed at a mean interval of 57 months after operation. Before surgery active extension lacked 43° which improved to 17° after operation. Active flexion before operation was 89°, which improved to 127°. The mean arc of movement increased from 46° to 110°. All 14 elbows showed scarring of the posterior oblique bundle of the medial collateral ligament. Neither the interval from injury to operative release nor the age of the patient affected the results. A medial approach is useful to reveal and excise the pathological changes in the medial collateral ligament. It is a safe and effective route through which to correct post-traumatic contracture of the elbow.

An X-band miniaturized traveling-wave tube (TWT) using a Spindt field emitter array (FEA) cathode was built. The FEA cathode has 542,000 molybdenum tips in an emission area 1.2 mm in diameter. It also has a trench current-limiter that shows low resistance in normal operation. A saturation output power of 28.2 W, a saturation power gain of 40 dB, and a beam transmission ratio of more than 99.3% have been achieved at a frequency of 11.5 GHz under 3% duty ratio.

Because the configurations of embedded DRAM macros vary for each product, designers normally must customize the test circuitry for each product. The authors have developed circuitry (Universal Test Interface) that unifies testing regardless of the DRAM configuration and the number of macros on a chip. The Universal Test Interface alleviates the contradiction inherent in embedded DRAM testing.

Genotypes of a queen and the first brood of workers of 20 colonies of Polistes chinensis antennalis were electrophoretically analyzed. We found allelic polymorphisms in two loci which encodes two enzyme, i.e., creatine kinase (CK) and isocitrate dehydrogenase (IDH). The genotype array of the first brood of workers in five colonies could not be explained by monoandry of the queen. Two to four suggested multiple mating of the queen, and one to three suggested replacement of the queen. Although multiple matings of some queens is apparent, the mean estimate of relatedness of the first brood of workers from the genotype frequency data, 0.648, is ambiguous, because it is not significantly different from 0.75 (one singly-mated queen) nor 0.545 (one doubly-mated queen).

We have investigates influence of existing trap states of TFT on device characteristics with use of the compact model HiSIM-TFT. Special focus is given on the 1/ƒ noise characteristics, where it is found the V gs dependence of the 1/ƒ noise characteristics is very sensitive to the trap density distributions. We have successfully extracted high density of the shallow trap states with the measured 1/ƒ noise characteristics.

The authors have analyzed the characteristics of a cylindrical thin-pillar transistor, (CYNTHIA), which is a vertical MOS transistor with a cylindrical gate electrode surrounding a submicrometer-diameter silicon pillar. The device characteristics are calculated by solving Poisson's equation in cylindrical coordinates. Results showed that CYNTHIA has three superior features: excellent subthreshold characteristics, enhanced electron mobility, and increased sheet electron concentration. These superior characteristics result in a feature size twice that of vertical SOI transistors, The authors' calculation is that CYNTHIA is quite an attractive device design for future ultra-high-density LSIs. >

We have developed a compact model of poly-Si TFTs based on complete surface-potential descriptions, including carrier trapping. The model was shown to be reliable for predicting high-speed circuit performances.

We developed a fully-LSI-process-compatible technology with excellent control of emitter shape for the first time. The fabricated emitter tip configuration has two-step-cone shape whose upper and lower cone configurations are controllable independently. While the upper parts determine the emitter tip sharpness and the apex angle, the lower parts determine the emitter height by utilizing two-step thermal oxidation for emitter tip sharpening in addition to anisotropic RIE for the emitter height control. The stable and uniform thermal oxidation for sharpening emitters realizes excellent uniformity, and the process without lift-off process is matched with Si LSI technology completely. The obtained 1944-tip emitter with 800 nm gate diameter showed low threshold voltage of 35 V.

We have successfully developed a novel Field Emitter Array (FEA) technology with low-leakage current between each emitter and its sub-half-micron diameter gate. This FEA has 0.38 micron gates, its emission threshold voltage is 24 V, and its leakage current has been reduced to less than a tenth of previous levels.

We first built two traveling wave tubes (TWTs) using a Spindt-type field emitter array (FEA) cathode. The first FEA-TWT achieved excellent RF performances. However its beam transmission ratio was only 82%, in contrast with more than 99% of a conventional TWT. To improve the beam transmission ratio and other characteristics, we re-designed the FEA electron gun and fabricated a second experimental FEA-TWT. At the current less than 20 mA, the beam transmission ratio of the second TWT was improved as high as 98%. However, when the current was more than 20 mA, space charge effect became significant and beam transmission ratio was rapidly degraded. The test results indicated that the design criteria for FEA electron guns needed to take into consideration the strong influence of space charge and how a good beam transmission ratio could be obtained.

We have developed highly reliable field emitter arrays with a novel vertical current limiter fabricated with a deep trench forming technology. The vertical current limiter has a local current-control function that automatically prevents fatal arc failure, and it has low resistance when used in the normal operation of a field emitter array. It has demonstrated a breakdown voltage as high as 120 V and a negligible increase in operation voltage, i.e., Vg of 70 V at 1 /spl mu/A/tip with an emitter cone density of more than 5/spl times/10/sup 7/ emitters/cm/sup 2/.

Genomic Object Net is a software tool for modeling and simulating biopathways which employs the notion of hybrid functional net as its basic architechture. This paper shows how to integrate this basic architecture with XML documents for biopathway representations, simulations, and visualizations for creating a tailor-made simulation environment.

We have implemented a system for assisting experts in selecting MEDLINE records for database construction purposes. This system has two specific features: The first is a learning mechanism which extracts characteristics in the abstracts of MEDLINE records of interest as patterns. These patterns reflect selection decisions by experts and are used for screening the records. The second is a keyword recommendation system which assists and supplements experts' knowledge in unexpected cases. Combined with a conventional keyword-based information retrieval system, this system may provide an efficient and comfortable environment for MEDLINE record selection by experts. Some computational experiments are provided to prove that this idea is useful.

A total of 64 patients with renal trauma were treated at the Department of Urology, St. Marianna University School of Medicine, from January 1988 to December 1996. Patients were between 3 and 66 years old (mean 28.2); 56 (87.5%) of them were male and 8 (12.5%) were female. The main cause of injury was a traffic accident in 33 cases (51.6%). According to the Classification of Renal Injury by the Japanese Association for the Surgery of Trauma in Japan, there were 27 cases (42.2%) of Type I (subcapsular injury), 12 cases (18.8%) of Type II (superficial injury), 16 cases (25.0%) of Type III (Deep injury), 6 cases (9.4%) of Type IV (Pedicle injury). Surgical treatment was performed in 6 cases (9.3%). The major associated injuries were bone fracture in 33 cases (51.6%), lung injury in 20 cases (31.3%) and liver injury in 16 cases (25.0%). The literature is also reviewed briefly.

We report successful treatment of acute severe Budd-Chiari syndrome with portal venous thrombosis. The prognosis of patients with this condition is poor, because the therapeutic options are limited. A 38-year-old woman with polycythemia vera was admitted in a critical condition, and Budd-Chiari syndrome complicated by portal venous thrombosis was diagnosed. Tissue plasminogen activator and urokinase were infused systemically and were partially effective. Transjugular intrahepatic portosystemic shunting to reduce the high portal venous pressure was performed successfully and, eventually, her general condition improved. Our experience indicates that emergency transjugular intrahepatic portosystemic shunting is an effective therapeutic modality for controlling portal hypertension in patients with severe Budd-Chiari syndrome with portal venous thrombosis.

A pharmacological adenosine-tri-phosphoric acid (ATP) stress test has been used in patients who can not perform an enough exercise stress test. However, falling blood pressure during the stress test and increased liver uptake of the tracer are often found in patients undergoing the ATP test. To prevent these phenomena, a combination of ATP stress test and low workload exercise test (ATPEX) is proposed. The usefulness of this newly developed stress test was elucidated from two viewpoints. Firstly, the changes of hemodynamic parameters were measured in 34 patients: 17 undergoing ATP alone and 17 undergoing ATPEX. Systolic blood pressure fell from 150 +/- 20 mmHg to 126 +/- 16 mmHg (p0.05) for ATP alone. However, it changed from 141 +/- 19 mmHg to 149 +/- 31 mmHg (ns) for ATPEX. There was a significant fall in systolic blood pressure (30 mmHg) in 58.8% for ATP alone and 5.9% for ATPEX (p0.01). Secondly, the ROI count in the liver and heart on an anterior projection image were measured in 38 patients: 11 undergoing ATP alone, 13 undergoing ATPEX, and 14 undergoing an ergometer exercise test (EX). The ROI count in the liver at 60 minutes after tracer injection were 29.0 +/- 10.7 count/pixel, 21.4 +/- 5.2 count/pixel, 18.3 +/- 4.5 count/pixel for ATP alone, ATPEX and EX, respectively. The activities for ATPEX and EX were lower than that for ATP alone (p0.05 and p0.01). Thus, ATPEX decreased the rates of the fall of systolic blood pressure and decreased liver uptake of the tracer compared with ATP alone. In conclusion, ATPEX is a useful stress method for myocardial perfusion scintigraphy in patients who can not perform the enough exercise stress test.

Shoulder subluxation in hemiplegic patients has been recognized as a difficult problem to manage. In the study contained herein, our aims are to evaluate shoulder subluxation, to clarify if shoulder subluxation causes pain, and to discuss the treatment of shoulder subluxation. The study included 75 hemiplegic patients with shoulder subluxation. Each patient was evaluated for the degree of shoulder pain, motor recovery of the upper limb, and shoulder range of motion. Some indexes for evaluating subluxation were measured with radiographs of the shoulders. Arthrograms of the affected shoulder joint were taken in 23 patients. The following results were found: (1) shoulder pain was significant more frequently in left hemiplegia; (2) vertical disparity was strongly correlated with discrepancy of the descendant ratio; (3) severe inferior subluxation had a tendency to show medial displacement of the humeral head; (4) there were correlations between shoulder pain and shoulder range of motion, especially external rotation; (5) adhesive changes in the arthrograms were seen in most subjects. These results indicate that there is no relation between shoulder subluxation and pain, and adhesive capsulitis is a main cause of shoulder pain. We conclude that correct positioning and shoulder range of motion exercises are advisable in hemiplegic patients with shoulder subluxation.

A comparative study of RD rate and the Barthel index was performed in 26 patients who had cerebral infarction. On 123I-IMP SPECT, the RD rate was calculated as follows, RD rate = (I-II)/I x 100(%). (I = (B-A)/B, where A is the mean count of the low density area (LDA) on brain CT on the early image and B the mean count of the opposite portion of LDA on the early image. II = (B'-A')/B', where A' is the mean count of the LDA on the delayed image and B' is the mean count of the opposite portion of the LDA on the delayed image. delta Barthel index (delta B. I.) was defined as follows: delta B. I. = B. I. (post-rehabilitation)-B. I. (pre-rehabilitation). In the group with B. I. (pre rehabilitation)85, the RD rate and delta B. I. were well correlated. In the group with B. I. (pre-rehabilitation)or = 85, the RD rate and delta B. I. were not correlated. This result suggests that the RD rate might be useful in predicting prognosis and selecting the principle of therapy.

Novel chiral aminophosphines, N,N-disubstituted diphenyl(1-amino-2-naphthyl)phosphines 4 were synthesized via nucleophilic aromatic substitution reaction on 1-methoxy-2-(diphenylphosphinoyl)naphthalene (1) by chiral lithium amides 2, followed by reduction of the phosphinoyl function. The new ligands were tested for their efficiency in the palladium-catalyzed allylic substitution of dimethyl malonate with 1,3-diphenyl-2-propenyl acetate and high asymmetric inductions up to 80%ee were observed.

We define a motif as an expression Z1.Z2...Zn with sets Z1, Z2,..., Zn of strings in a specified family omega called the type. This notion can capture the most of the motifs in PROSITE as well as regular pattern languages. A greedy strategy is developed for finding such motifs with ambiguity just from positive and negative examples by exploiting the probabilistic argument. This paper concentrates on describing the idea of the greedy algorithm with its underlying theory. Its experimental results on splicing sites and E. coli promoters are also presented.

We have developed a machine discovery system BONSAI which receives positive and negative examples as inputs and produces as a hypothesis a pair of a decision tree over regular patterns and an alphabet indexing. This system has succeeded in discovering reasonable knowledge on transmembrane domain sequences and signal peptide sequences by computer experiments. However, when several kinds of sequences are mixed in the data, it does not seem reasonable for a single BONSAI system to find a hypothesis of a reasonably small size with high accuracy. For this purpose, we have designed a system BONSAI Garden, in which several BONSAI's and a program called Gardener run over a network in parallel, to partition the data into some number of classes together with hypotheses explaining these classes accurately.