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Two-photon imaging is a major recording technique in neuroscience but its low sampling rate imposes a severe limit of elucidating high temporal profiles of neuronal dynamics. Here we developed two hyperacuity Bayesian algorithms to improve spike detection and spike time precision, minimizing the estimation error supervised by the ground-truth given as the electrical spike signals. The benchmark showed that our algorithms outperformed other unsupervised algorithms maximizing the likelihood of the estimates for both experimental and simulation data. We argue that the supervised algorithms are useful tools to improve spike estimation of two-photon recording in case ground truth signals are available.

BACKGROUNDS AND PURPOSE Lactic acidosis is a fatal adverse effect of metformin, but the risk factor remains unclear. Multidrug and toxin extrusion 1 (MATE1) is expressed in the luminal membrane of the kidney and liver. MATE1 was revealed to be responsible for the tubular and biliary secretion of metformin. Therefore, some MATE polymorphisms, that cause it to function abnormally, are hypothesized to induce lactic acidosis. The purpose of this study is to clarify the association between MATE dysfunction and metformin-induced lactic acidosis. EXPERIMENTAL APPROACH Blood lactate, pH and bicarbonate ion (HCO3-) levels were evaluated during continuous administration of 3 mg·mL−1 metformin in drinking water using Mate1 knockout (−/−), heterozygous (+/−) and wild-type (+/+) mice. To determine the tissue accumulation of metformin, mice were given 400 mg·kg−1 metformin orally. Furthermore, blood lactate data were obtained from diabetic patients given metformin. KEY RESULTS Seven days after metformin administration in drinking water, significantly higher blood lactate, lower pH and HCO3- levels were observed in Mate1−/− mice, but not in Mate1+/− mice. The blood lactate levels were not affected in patients with the heterozygous MATE variant (MATE1-L125F, MATE1-G64D, MATE2-K-G211V). Sixty minutes after metformin administration (400 mg·kg−1, p.o.) the hepatic concentration of metformin was markedly higher in Mate1−/− mice than in Mate1+/+ mice. CONCLUSION AND IMPLICATIONS MATE1 dysfunction caused a marked elevation in the metformin concentration in the liver and led to lactic acidosis, suggesting that the homozygous MATE1 variant could be one of the risk factors for metformin-induced lactic acidosis.

This paper describes results obtained from analysis and experiments done on a fluxgate dc earth leakage current sensor for electric vehicles and photovoltaic power generation systems. As fluxgate current sensors are extremely sensitive to room temperature, various applications need this characteristic. However, conventional fluxgate current sensors have a problem in that they can only measure a narrow range of currents. To address this issue, we propose that the turns of the excitation coil be optimized with a simulator. This new sensor consists of a coiled wire that is wound around a toroidal amorphous core and through a bus bar. The sensor detects variations in excitation current according to dc current. The sensor was analyzed with a simulator. The magnetic field simulator was used to calculate the excitation current, and the output voltage according to the excitation current was calculated with a circuit simulator. We found that the results from simulations almost corresponded to those from measurements, and were able to verify the validity of the basic analytical model. As a result of analysis with the simulator, 35 turns of the excitation coil were used to achieve a wide range of measurements of ±600 mA.

The Young's moduli and wear characteristics of two cermet coatings were evaluated under normal atmosphere. The tested coatings were WC/12 per cent Co and Cr3C2/25 per cent NiCr made by using high-velocity oxygen fuel spraying. The Young's moduli of the coatings were obtained using cantilever bend tests. The wear characteristics were evaluated on a wear test apparatus. The WC/12 per cent Co was superior to Cr3C2/25 per cent NiCr in view of wear resistance. The Cr3C2/25 per cent NiCr coating exhibited low friction at higher temperature. A relation was found between the Young's modulus, hardness, wear resistance, and the offensiveness to the mating material of the tested coatings.

In order to investigate the crack path under Mode II or Mode III loadings, reversed torsion tests were carried out on SAE52100 and Mode II fatigue crack growth tests were carried out on 0.47% carbon steel specimens. In the torsional fatigue test (SAE52100), the type of inclusion at the torsional fatigue fracture origin was slender MnS inclusions which were elongated in the longitudinal direction. The cracks first propagated by Mode II up to crack length 2a = 100–200 μm (which are almost equal to the length of MnS inclusion) in the longitudinal direction, and then branched by Mode I to the direction (∼ ± 70.5°) perpendicular to the local maximum normal stress (σθmax) at the crack tip. In the Mode II fatigue crack growth test (0.47% carbon steel) in air and in a vacuum, the cracks first propagated by Mode II. After the Mode II fatigue crack growth stopped, the crack branched to the direction perpendicular to the local maximum normal stress (σθmax) at the crack tip, and finally branched to the angle close to the direction perpendicular to the remote maximum principal stresses. A fibrous pattern on the Mode II fatigue fracture surface tested in a vacuum was clearer than that in air. The Mode II threshold stress intensity factor ranges, ΔKIIth = 10.2 MPa m (Longitudinal crack) and ΔKIIth = 12.5 MPa m (Transverse crack) in a vacuum were higher than those in air, ΔKIIth = 9.4 MPa m (Longitudinal crack) and ΔKIIth = 10.8 MPa m (Transverse crack). Both in vacuum and in air, the values of ΔKIIth for crack growth perpendicular to the rolling direction were higher than those for crack growth parallel to the rolling direction. The values of KII and KIII at a 3D elliptical crack tip under shear stress were analyzed to investigate the shear crack growth pattern in materials. The 3D crack analysis shows that the most stable aspect ratio b/a of a small planar elliptical crack under cyclic shear stress is b/a = 0.49 in absence of friction on the crack surfaces. The aspect ratio b/a = 0.49 can be explained by the equal resistance against fatigue crack growth both in Mode II and Mode III, i.e., ΔKIIth = ΔKIIIth. However, the aspect ratio b/a for the failure of a real railway wheel did not stay at the stable aspect ratio b/a = 0.49 and continued decreasing. The cause for the decrease in the aspect ratio b/a smaller than 0.49 was revealed to be the friction between crack surfaces.

In order to investigate the crack path in materials containing a small crack under mixed mode loading, reversed torsion and combined push-pull/torsion fatigue tests were carried out on 0.47% carbon steel specimens containing an initial small crack. The initial small cracks were introduced by a preliminary push-pull fatigue test using a specimen that contained an artificial small hole of 40 μm diameter/depth. Push-pull fatigue tests followed by reversed torsion, and reversed torsion followed by push-pull were carried out. Fatigue tests of combined push-pull/torsion followed by push-pull were also carried out to examine the effect of crack geometry, such as branching and kinking, on cumulative fatigue damage. Different crack growth behaviours due to different loading modes and sequences complicatedly influenced the fatigue crack path and eventually the cumulative fatigue damage. Thus, existing fatigue damage theories cannot be applied to the cases presented in this study. A single factory roof morphology was formed on the fracture surface of the specimen having an initial semielliptical surface crack under cyclic torsion. Taking the result into consideration, torsional fatigue tests of circumferentially cracked specimens were carried out to investigate the Mode III crack growth threshold and the formation mechanism of the factory roof. It was found that the factory-roof pattern was formed by Mode I crack branching from small semielliptical cracks nucleated ahead of the circumferential crack tip. Thus, stress intensity factors at the semielliptical crack tip ahead of the circumferential crack tip were analysed to make the mechanism of crack branching from the semielliptical crack clear. The analysis shows that the Mode III stress intensity factor, K III , at the deepest point of the semielliptical crack decreases with increase in the depth of semielliptical crack. It follows that as the shear crack growth becomes difficult at the semielliptical crack tip, crack branching starts at the major axis ends in the direction for Mode I growth, forming factory roof, due to ΔK Ith < ΔK IIIth .

The central nervous system of persons with Down syndrome presents cytoarchitectural abnormalities that likely result from gene-dosage effects affecting the expression of key developmental genes. To test this hypothesis, we have investigated the transcriptome of the cerebellum of the Ts1Cje mouse model of Down syndrome during postnatal development using microarrays and quantitative PCR (qPCR). Genes present in three copies were consistently overexpressed, with a mean ratio relative to euploid of 1.52 as determined by qPCR. Out of 63 three-copy genes tested, only five, nine and seven genes had ratios >2 or

We are developing an elemental technology for 66/6.9 kV 20 MVA-class superconducting power transformer with fault current limiting function. In order to obtain the characteristics of YBCO conductor when the AC over current supplied to the conductor, the model coils were manufactured with YBCO tapes and tested. Based on these results, we manufactured the 6.9 kV/2.3 kV 400 kVA-class YBCO model transformer with fault current limiting function and performed short-circuit test. At the 0.25 s after short-circuit, the short-circuit current of primary winding was limited to about 174 A for a prospective current of 559 A. It was consistent with the design. The I–V characteristics of the winding did not change before and after the test. We consider the model transformer to be able to withstand AC over-current with the function of current limiting. The results suggest the possibility to design YBCO superconducting transformers with fault current limiting function for practical power grid.

Quantitative crossed cerebellar diaschisis (CCD) and the correlation with a reduction in supratentorial regional cerebral blood flow (rCBF) and cerebrovascular reserve capacity (CVR) were investigated in clinically stable patients with major cerebral artery occlusion by the iodine-123-N-isopropyl-p-iodoamphetamine (I-123 IMP) single photon emission computed tomography (SPECT) method. Thirty patients with major cerebral artery occlusion underwent SPECT by the I-123 IMP autoradiographic method. Regional CBF was measured in the cerebral hemisphere, frontal and parietal lobes, temporo-parietal lobe, and cerebellum both at rest and after administration of acetazolamide. Eighteen of 30 patients (60%) had CCD. CCD was significantly related to magnetic resonance imaging evidence of infarction. Quantitative CCD was 17% and the CVR in the cerebellum was preserved in patients with CCD. There was a significant difference in CBF and CVR between the affected and normal sides in all regions of interest in the patients without CCD [CBF (ml/100 g/min): hemisphere (H), normal side (N): 31.4 +/- 6.8, affected side (A): 27.5 +/- 7.4; p0.05. CVR: H, N: 0.56 +/- 0.38, A: 0.42 +/- 0.18; p0.01]. CCD is common in patients with major cerebral artery occlusion, and quantitative I-123 IMP SPECT is helpful in detecting CCD in clinically stable patients with occlusion of major cerebral arteries.

Independent component analysis (ICA) is a new, simple and powerful idea for analyzing multi-variant data. One of the successful applications is neurobiological data analysis such as electroencephalography (EEG), magnetic resonance imaging (MRI), and magnetoencephalography (MEG). However, many problems remain. In most cases, neurobiological data contain a lot of sensor noise, and the number of independent components is unknown. In this article, we discuss an approach to separate noise-contaminated data without knowing the number of independent components. A well-known two stage approach to ICA is to pre-process the data by principal component analysis (PCA), and then the necessary rotation matrix is estimated. Since PCA does not work well for noisy data, we implement a factor analysis model for pre-processing. In the new pre-processing, the number of sources and the amount of sensor noise are estimated. After the pre-processing, the rotation matrix is estimated using an ICA method. Through the experiments with MEG data, we show this approach is effective.

To identify the most useful combinations of various pre- and postcontrast magnetic resonance (MR) image sequences in detecting hepatocellular carcinoma (HCC) and its intrahepatic metastases before and after injection of SHU-555-A.Thirty-eight lesions in 16 patients were evaluated before and after administration of SHU-555-A by using fast spin echo (FSE), gradient echo (GRE), and echo planar (EP) imaging sequences using a 1.5-Tesla superconducting MR system. The signal intensity ratio (SIR) and contrast-to-noise ratio (CNR) of the lesions, signal-to-noise ratios, and other parameters were calculated.Tumors were better detected after injection of SHU-555-A on all pulse sequences except on out-of-phase T1-weighted (T1W)-GRE sequences. Tumor detectability was higher for precontrast EP imaging and T2*-weighted (T2*W)-GRE sequences, whereas detectability at postcontrast was higher for T2*W-GRE, proton-density-weighted-FSE, and in-phase T1W-GRE sequences. The SIR and CNR at precontrast were highest for EP imaging, and those at postcontrast were highest for T2*W-GRE.SHU-555-A will increase the detectability of HCC and its liver metastases. T1W- and T2*W-GRE sequences would be the sequences of choice.

The aim of this study was to compare dual-isotope ( 99 Tc m and 201 Tl) SPET imaging with computed tomography (CT) and magnetic resonance imaging (MRI) in the differentiation of various lesions of the major salivary glands. Twenty-two patients underwent dual-isotope SPET imaging, of whom 12 also had CT and 15 also had an MRI study. The uptake ratio and retention index for 99 Tc m and 201 Tl were calculated by drawing regions of interest on the involved and normal glands. Both CT and MRI were interpreted by two radiologists. All malignant tumours were detected by all three modalities. Warthin's tumours were detected by dual-isotope SPET imaging; however, MRI failed to differentiate Warthin's tumour from pleomorphic adenoma. Of 13 other benign tumours, dual-isotope SPET correctly diagnosed 12. Of 16 tumours showing a cold defect on the 99 Tc m images, parametric analysis with 201 Tl gave an accuracy of 94%, whereas CT gave an accuracy of 70-90%. MRI was 73-91% accurate in differentiating between benign (Warthin's) and malignant tumours. We believe that dual-isotope SPET imaging ( 99 Tc m and 201 Tl), together with semi-quantitative analysis, is the method of choice for differentiating between various lesions of the major salivary glands.

Early dynamic and late 123 I-MIBG SPET studies were performed to investigate several parameters used to distinguish the characteristics of various cardiac disorders. Forty-six individuals (34 non-diabetic, 12 diabetic) with or without heart disease were included in the study. Early dynamic and late static SPET images were acquired using a triple-headed gamma camera. After selecting mid-sections from vertical (VLA) and horizontal (HLA) long-axis images, regions of interest were created over the apex, whole heart and anterior, inferior, septal and lateral walls of the heart. Various uptake ratios at 3, 11 and 19 min and 4 h after injection (HU3, HU11, HU19, DUP) and clearances (K se : between HU3 and HU11; K e : between HU11 and HU19; K d : between HU19 and DUP) were calculated. There were significant differences among various cardiac pathologies on the delayed images. Cardiomyopathy patients showed the lowest uptake on the delayed images. When all segments in normal patients and all involved segments in myocardial infarcted patients were compared, there was significantly lower uptake of MIBG in infarcted segments at all time points. K d showed the lowest value compared with K se and K e . In cardiomyopathy patients, K se , K e and K d were significantly different from each other. Both K se and K e were significantly higher in cardiomyopathy patients than in normal patients. In conclusion, the results of this study are in line with published data and precise measurement of uptake and clearance was possible when excluding background and blood pool activity.

The aim of this study was to characterize lung lesions by means of the uptake, retention and washout of 201 Tl, and to quantify the sensitivity of 201 Tl SPET (single photon emission tomography) in detecting mediastinal and hilar lymph nodes. A total of 68 patients with lung lesions (tumours and inflammation) underwent both helical computed tomography (CT) and 201 Tl SPET examinations. Uptake, retention and washout parameters were calculated from early and delayed 201 Tl SPET by drawing regions of interest over the primary lesion and the background of the lung. The findings on 201 Tl SPET were compared with those on CT and surgical findings. A significant difference in the retention index (RI) was observed between primary malignant and benign lesions. In detecting lymph nodes, the sensitivity, specificity and negative predictive value were 83%, 60% and 90% respectively for early 201 Tl SPET, and 50%, 80% and 80% respectively for delayed 201 Tl SPET. 201 Tl SPET with semi-quantitative analysis, especially RI, helps to differentiate between malignant and benign lung lesions. Lymph nodes larger than 1 cm on CT but not showing 201 Tl uptake could be considered non-metastatic lesions.

Axles are one of the most important components in railway vehicle with regard to safety, since a fail-safe design is not available. To maintain the safety record of high speed railway systems, the fatigue strength of the axles has been extensively studied. The objective of the present paper is to review and analyse the causes of failure in railway axles, and to show how the results have been applied to improve axle manufacture and in-service inspection. The problems of fretting fatigue crack initiation at press-fitted axle parts is emphasized, however, these problems have not been completely solved even though up-to-date fatigue design methods are employed. The safety of the railway has been ensured by maintenance such as the regular inspection for fatigue cracks at critical parts.

The kinetics, intracellular distribution and effects of ion transport inhibitors on the uptake of 99 Tc m -tetrofosmin, 99Tcm-methoxyisobutyl isonitrile ( 99 Tc m -MIBI) and 201 Tl were investigated in a tumour cell line. Both uptake and washout of the tracers were measured at specific intervals. Cells were treated with ouabain, dimethyl amiloride (DMA) and bumetanide to observe the effects on uptake, while carbonyl cyanide m-chlorophenylhydrazone (CCCP) was used to study the release of the tracers. The tracers showed similar uptake and washout kinetics. Ouabain inhibited 55-67% of 201 Tl, 16-22% of 99 Tc m -tetrofosmin and 8-14% of 99 Tc m -MIBI. DMA inhibited the uptake of both 99 Tc m -tetrofosmin (30%) and 99 Tc m -MIBI (21%). Bumetanide stimulated the uptake of 99 Tc m -tetrofosmin and 99 Tc m -MIBI but inhibited that of 201 Tl (37%). When cells were pretreated with various combinations of these ion transport inhibitors, the uptake of 201 Tl was related to Na + ,K + pump, Na + ,K + ,2Cl - co-transport systems, whereas the uptake of both 99 Tc m -tetrofosmin and 99 Tc m -MIBI was related to the Na + ,K + pump, Na + /H + antiport systems. Addition of CCCP released 55% and 90% of accumulated 99 Tc m -tetrofosmin and 99 Tc m -MIST respectively, indicating that the percentage released was related to mitochondrial uptake.

Automatic determination of the cell shapes of large numbers of melanocytes based on optical images of human skin models have been largely unsuccessful (the complexities introduced by dendrites and the melanin pigmentation over the keratinocytes to give unclear outlines). Here, we present an image enhancement procedure for enhancing the contrast of images with removing the non-uniformity of background. The brightness is normalized also for the non-uniform population density of melanocytes.

We report scan findings of Tl-201 in a case of histologically proved Warthin’s tumor. Dual isotopes acquisition was performed in a case of left parotid Warthin’ s tumor. Both early and delayed Tc-99m-pertechnetate (Tc-99m) images showed increased uptake at the tumor. Tl-201 scan also showed an increase of uptake on the early image and retention on the delayed image. The uptake ratios of Tl-201 were 3.0 (early) and 2.3 (delayed). Scan findings of Tl-201 in a case of Warthin’s tumor were similar to those of Tc-99m, and the interpretation of Tl-201 images should be accompanied with Tc-99m images.

Investigates the analysis of a hyperthermic treatment. The time dependent electromagnetic-heat transfer equations are solved step-by-step considering the temperature dependencies of relative permittivity /spl epsiv//sub r/ and electric conductivity /spl sigma/. Close agreement between the calculated and measured temperature distributions is obtained. A technique to direct the electromagnetic energy toward a specific part of a homogeneous torso model is also noted.

This study shows theoretical and experimental results on three main effects determining the frequency stability of a Brillouin fiber ring laser, namely: the temperature effects and the nonlinear Kerr and frequency pulling effects. The oscillation frequency in a Brillouin fiber ring laser is determined mainly by the axial mode of the cold resonator located under the Brillouin gain curve that experiences the highest gain. This oscillation frequency is therefore temperature dependent since both the free spectral range (FSR) and the gain curve center depend on the temperature. The FSR variation gives rise to a continuous lasing frequency variation while the gain curve shift leads to mode hopping. In addition to these temperature effects, the nonlinear Kerr effect and the mode pulling effect will also slightly shift the lasing frequency away from the resonant frequency of the cold resonator. The Kerr effect depends only on the pump power, while the mode pulling effect depends on both the pump power and the relative location between the lasing mode and the gain curve center. The results of this study are useful in many BFRL applications such as Brillouin fiber-optic gyroscopes, microwave generators and frequency shifters. >

Important factors surrounding chest surgery for the patients complicated with digestive disease were discussed according to the experiences of clinical settings.Check points regarding each context, preoperative, perioperative, postoperative, and outpatient care were considered independently.If digestive diseases are uncontrolled, the operation should be postponed until they are appropriately cared. Dental problems such as teeth caries or denture insufficiency should be cleared preoperatively. Dysphagia after the head and neck surgery must be evaluated and alternative feeding methods should be established. The patients with digestive tract disorder have malabsorption and are prone to malnutrition. According to the appropriate assessments of digestion and absorption, an enteral nutrition or a total parenteral nutrition should be considered before and after operation, to improve nutrition status. Immunonutrition is particularly beneficial to reduce the postoperative infection or various stresses of invasive operations in the chest surgery. Chronic pancreatitis is characterized by absorption impairment and pancreatic diabetes. They should also be controlled before the operation using digestive enzymes and an exogenous insulin.Teeth problems, dysphagia, malabsorption, malnutrition and pancreatic diabetes should be assessed and cared appropriately before and after the chest surgery using compensative therapy.

PURPOSE: To determine whether adrenal adenomas can be differentiated from metastases on fat-saturated magnetic resonance (MR) images. MATERIALS AND METHODS: Twenty-eight adrenal adenomas and 20 metastatic lesions were imaged at 1.5 T by means of fat-saturated T1- and T2-weighted and gadolinium-enhanced T1-weighted sequences. The authors evaluated visually whether structures of high signal intensity (hyperintense rim sign) could be observed in the outer margin of the adrenal masses. RESULTS: Twenty-six of 28 adrenal adenomas revealed the hyperintense rim sign on at least one kind of fat-saturated image, compared with only one of 20 metastases. The sensitivity of the hyperintense rim sign as suggestive of adrenal adenoma was 92%, specificity was 95%, and overall accuracy was 94%. CONCLUSION: The hyperintense rim sign is characteristic of adrenal adenomas. Thus, adrenal adenomas can be differentiated from metastases by means of this new imaging sign on fat-saturated MR images.

We have fabricated a muscle-powered micro gripper controlled by electromyogram (EMG) signals as one step toward development of a teleoperated micromanipulator. We utilized human muscles EMG signals as the master control and tissue-engineered skeletal muscles as the slave actuator. This muscle-to-muscle interface for master-slave control is useful for improvement of teleoperated micromanipulation. We designed the SU-8 micro gripper and fabricated tissue-engineered skeletal muscles which have similar properties to natural muscles. Moreover, we successfully teleoperated the displacement of the muscle-powered micro gripper with EMG signals of a human.

The stereoselective deuterium labeling at the 5' methylene protons of the ribose ring recently developed by Kawashima et al. [1995, Tetrahedron Lett., 36, 6699-6700] enabled the assignment of pro-R and pro-S protons at the 5' position. The deuterium-labeled nucleotides, [(5'S)-(2)H]- and [(5'R)-(2)H]-diastereomers, in an approximate ratio of 2:1, were incorporated in the decamer 5'-d(GCATTAATGC)-3'. Thus, both pro-R and pro-S methylene proton signals without geminal coupling appeared in the NOESY and DQF-COSY spectra. Complete stereospecific assignments and simplified spin systems enabled the determination of 15 (3)J coupling constants between H4' and H5'/H5", and the unambiguous assignment of 135 NOESY cross peaks originating from H4'/H5'/H5" resonances.

Temperature effects in a Brillouin fiber ring laser have been investigated. The results show that temperature plays a major role in many different laser characteristics such as lasing frequency, mode hopping, spontaneous pulsing, and frequency mode pulling. Thermal coefficients for the Brillouin frequency shift and for the frequency difference between the pump wave and the first-Stokes wave were measured and are consistent with theoretical predictions based on published basic material parameters. Experimental observation and measurement of the temperature dependence of the spontaneous pulsing threshold show that temperature is a key parameter that may be important in uncovering the physical mechanism underlying spontaneous pulsing.

A synthetic heterodyne detection scheme for ring-laser gyros to sense both rotation rate and direction is presented. This scheme is compatible with the sinusoidal push–pull phase-modulation technique for suppressing frequency locking. The good experimental results achieved in a fiber-optic Brillouin ring-laser gyro show the potential of this detection scheme in applications.

A novel demodulation scheme for interferometers with optical phase modulation is described. The optical phase shift is measured by mixing a train of square digital pulses with a photodetector current and adjusting the pulse spacing by using an electronic closed loop. The optical phase shift is tracked with deviation less than 0.007 rad, which can be easily corrected by using a look-up table. An experimental optically open-loop fiber-optic gyroscope that uses this demodulation shows a linear scale factor in good agreement with theory.

1. Intracellular recording was made from layer II-III cells in slice preparations of kitten (30-40 days old) visual cortex. Low-frequency (0.1 Hz) stimulation of white matter (WM) usually evoked an excitatory postsynaptic potential (EPSP) followed by an inhibitory postsynaptic potential (IPSP). The postsynaptic potentials (PSPs) showed strong dependence on stimulus frequency. Early component of EPSP and IPSP evoked by weak stimulation both decreased monotonically at frequencies greater than 0.5-1 Hz. Strong stimulation similarly depressed the early EPSP at higher frequencies (greater than 2 Hz) and replaced the IPSP with a late EPSP, which had a maximum amplitude in the stimulus frequency range of 2-5 Hz. 2. Very weak WM stimulation sometimes evoked EPSPs in isolation from IPSPs. The falling phase of the EPSP revealed voltage dependence characteristic to the responses mediated by N-methyl-D-aspartate (NMDA) receptors and was depressed by application of an NMDA antagonist DL-2-amino-5-phosphonovalerate (APV), whereas the rising phase of the EPSP was insensitive to APV. 3. The early EPSPs followed by IPSPs were insensitive to APV but were replaced with a slow depolarizing potential by application of a non-NMDA antagonist 6,7-dinitro-quinoxaline-2,3-dione (DNQX), indicating that the early EPSP is mediated by non-NMDA receptors. The slow depolarization was mediated by NMDA receptors because it was depressed by membrane hyperpolarization or addition of APV. 4. The late EPSP evoked by higher-frequency stimulation was abolished by APV, indicating that it is mediated by NMDA receptors, which are located either on the recorded cell or on presynaptic cells to the recorded cells. 5. Long-term potentiation (LTP) of EPSPs was examined in cells perfused with solutions containing 1 microM bicuculline methiodide (BIM), a gamma-aminobutyric acid (GABA) antagonist. WM was stimulated at 2 Hz for 15 min as a conditioning stimulus to induce LTP, and the resultant changes were tested by low-frequency (0.1 Hz) stimulation of WM. 6. LTP of early EPSPs occurred in more than one-half of the cells (8/13) after strong conditioning stimulation. The rising slope of the EPSP was increased 1.6 times on average. 7. To test involvement of NMDA receptors in the induction of LTP in the early EPSP, the effect of conditioning stimulation was studied in a solution containing 100 microM APV, which was sufficient to block completely synaptic transmission mediated by NMDA receptors. LTP occurred in the same frequency and magnitude as in control solution.

The full range of possibilities for spoken-language technologies (SLTs) to impact poor communities has been investigated on partially, despite what appears to be strong potential. Voice interfaces raise fewer barriers for the illiterate, require less training to use, and are a natural choice for applications on cell phones, which have far greater penetration, in the developing world than PCs. At the same time, critical lessons of existing technology projects in development still apply and require careful attention. We suggest how to expand the view of SLT for development, and discuss how its potential can realistically be explored.

We investigate small direct current interruption phenomena by vacuum interrupters. When a small current is interrupted by a vacuum circuit breaker, the arc dynamic behavior such as oscillation phenomena play important roles, and these depend on discharge states between contacts. In this paper, we observed these dynamic responses immediately after some disturbance has been applied to a small DC arc current.

Using DNP with zeolite powders and TEMPO, we have developed a method to enhance polarization of liquid 3He. At magnetic field of 2.5 T and a temperature of around 1.5 K, we have obatined polarization enhancement of liquid 3He, 2.34 and −1.59 for positive and negative enhancements, respectively.

Patients whose Ga-67 whole-body images showed increased uptake by the bone/bone marrow of the lower extremities were selected and classified into three types according to the extent and the grade of the visualization. These types were then compared with their serum iron levels, iron-binding capacities, and the results of several other serum biochemical tests. Of 374 consecutive whole body 72-hr images reviewed, 59 (15.8%) showed increased uptake of the tracer by the bone/bone marrow of the lower extremities. The three classified types were as follows: type T--visualization of both tibiae and femurs; type S--strong visualization of the femurs; and type W--weak visualization of the femurs. The serum iron concentration was significantly high in type T and low in type S. In conclusion, the pattern of Ga-67 uptake by the bone/bone marrow of the lower extremities fairly closely reflects the status of iron metabolism.

We present a method of measuring VoIP traffic fluctuation by using netflow or sFlow. As the traffic of critical applications such as VoIP has increased in backbone networks, network operators need to measure the QoS performance of traffic in real networks more easily and passively. We have studied the delay and fluctuation of VoIP traffic in a real network and focused on traffic fluctuation that can be measured at one observation point. We evaluated the effectiveness of this method using selective sFlow, which has been implemented in a commercial router

A 31-year-old male having familial amyloid polyneuropathy underwent a Tc-99m(V)-DMSA study to evaluate the myocardial involvement. The patient also underwent T1-201, I-123-BMIPP and I-123-MIBG myocardial SPECT studies to evaluate blood perfusion, fatty acid metabolism and sympathetic function of the heart, respectively. Tc-99m(V)-DMSA SPECT showed uptake to the myocardium indicating myocardial involvement of amyloidosis. Both T1-201 and I-123-BMIPP studies showed normal uptake indicating normal blood perfusion and fatty acid metabolism but I-123-MIBG SPECT showed no uptake to the heart, indicating severe impairment of sympathetic function.

Fuji Electric has developed a pulse tube cryocooler (PTC) with in‐line configuration with a cooling capacity of 3 W at 70 K and requiring 100 W of electrical input power. The emphasis has been on compactness, lightweight, high performance and low cost. In particular, the dimensions of the PTC have been reduced to a width of 190 mm and a height of 300 mm. Presently, we are developing a U‐shaped PTC based on the technology of the in‐line PTC. The advantage of the U‐shaped PTC is that the cold head is located at the end for easy accessing. The key issue for developing the U‐shaped PTC is the design of the flow straightener at the cold head. As a first step in the development we visualized the inside of the pulse tube by using particle image velocimetry (PIV). The design of the flow straightener is based on the visualization results. Preliminary tests indicated that the cooling performance of the U‐shaped PTC is 2 W at 70 K while requiring 51 W PV power. We will present the test results on the U‐shaped PTC as...

Fuji Electric has designed, fabricated and tested a 70 K pulse tube cryocooler. The cryocooler was designed for commercial use to provide 2 to 3 W at 70 K. The basic concept of this cryocooler is compactness, low cost, high reliability and high performance. A compressor is a key part for providing a compact cryocooler. The compressor is composed of dual-opposed-pistons that move with a coil. A new concept for supporting the moving units with flexure bearings enables a smaller size in the axial direction. The reduction or integration of parts significantly diminishes the cost of the compressor. The pulse tube part of the cryocooler is implemented in an in-line configuration in order to provide high cooling performance. Dimensions of the pulse tube, regenerator geometry and phase shifter are optimized by experimental methods. In addition, the cooling performance has been enhanced by optimization of the compressor. Application of these technologies enables the pulse tube cryocooler to provide a cooling capacity of 2.5 W at 70 K with 100 W electrical input. Reliability is one of the most important requirements, and component reliability tests, which include mechanical fatigue of the flexure bearings and contamination of the helium working gas, were conducted. The lifetime of the cryocooler is expected to be more than 50,000 hours.

The lasing frequencies of a Brillouin fiber ring laser are shifted slightly from the resonant frequencies of the cold fiber ring resonator due to the optical Kerr effect and the nonlinear phase shift associated with stimulated Brillouin scattering (SBS) used as the gain mechanism in this type of laser. These frequency pulling effects are investigated in detail both theoretically and experimentally. The results of this study are useful in many Brillouin fiber ring laser applications such as Brillouin fiber optic gyroscopes, microwave generators, and frequency shifters. To the authors' knowledge this is the first time the frequency pulling effect caused by the nonlinear phase shift associated with SBS is reported. >

It is often tedious and expensive to label large training data sets for learning-based object recognition systems. This problem could be alleviated by self-supervised learning techniques, which take a hybrid of labeled and unlabeled training data to learn classifiers. Discriminant-EM (D-EM) proposed a framework for such tasks and current D-EM algorithm employed linear discriminant analysis. However, the algorithm is limited by its dependence on linear transformations. This paper extends the linear D-EM to nonlinear kernel algorithm, Kernel D-EM, based on kernel multiple discriminant analysis (KMDA). KMDA provides better ability to simplify the probabilistic structures of data distributions in a discrimination space. We propose two novel data-sampling schemes for efficient training of kernel discriminants. Experimental results show that classifiers using KMDA learning compare with SVM performance on standard benchmark tests, and that Kernel D-EM outperforms a variety of supervised and semi-supervised learning algorithms for a hand-gesture recognition task and fingertip tracking task.