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A photon counting imaging detector system for high energy X-rays is developed for on-site non-destructive testing of thick objects. One-dimensional silicon strip (1 mm pitch) detectors are stacked to form a two-dimensional edge-on module. Each detector is connected to a 48-channel application specific integrated circuit (ASIC). The threshold-triggered events are recorded by a field programmable gate array based counter in each channel. The detector prototype is tested using 950 kV linear accelerator X-rays. The fast CR shaper (300 ns pulse width) of the ASIC makes it possible to deal with the high instant count rate during the 2 μs beam pulse. The preliminary imaging results of several metal and concrete samples are demonstrated.

In IEC-60060-1 as revised in 2010, a conversion method for lightning impulse voltage test waveforms using the test voltage function (K-factor function) was adopted. Presently, studies are being conducted on the test standards for ultra-high voltage (UHV)-class equipment. Since the existing K-factor function was established based on the experimental results for more small models compared with the insulation structure of UHV-class equipment, the issue has arisen as to whether this K-factor function can also be applied for UHV-class equipment. The authors experimentally obtained K-factor values using the largest possible model assuming UHV-class equipment in the previous studies. This paper reports the K-factor values and the insulation characteristics with respect to the front time obtained for air insulation under a negative-polarity lightning impulse voltage. According to the results of this experiment, even though the K-factor values for an air gap were likely to be slightly lower than the existing K-factor function in the negative polarity, the tendency of the change with respect to the superimposed oscillation frequency was similar. Furthermore, it was found that even though the breakdown voltage for waveforms with an extended front time was likely to decrease further than that for the standard lightning impulse waveforms, the decline was about 3.1% even for a front time of 4.8 nμ s. Consequently, it was indicated that a lightning impulse voltage test waveform with an extended front time may help properly verify the insulation performance of a UHV-class air bushing.

Measured deposited energies by 3 to 70 MeV protons and 9.5 to 24.5 MeV/nucleon alpha particles in partially depleted silicon detectors were 2 to 5 times larger than calculated deposited energies in an original depletion layer. All released charge carriers within a charge-collection length were collected. The charge-collection lengths are found to be independent of particle species, energies and stopping powers but dependent on the original depletion layer thickness. An empirical equation as a function of the depletion layer thickness is introduced to calculate the charge-collection length and the deposited energy in the silicon detectors.

We developed a small size silicon detector composed of a silicon radiation sensor, an analogue amplifier circuit and a sensor bias filter circuit by using a silicon circuit board for use in digital circuit applications. Our detector could be downsized by forming built-in electrical parts of small thin film on the silicon circuit board with a narrow wiring patterns of 20 μ m width through the Micro Electronics Mechanical System manufacturing process and by eliminating the ceramic case through the direct silicon sensor mounting. Our detector is - 85 % smaller than the commercially available detector using the plastic circuit board that has the same sensor and the same circuit covered with a ceramic case. The physical characteristics, such as the energy response and the linearity to dose equivalent rate, of the newly developed detector were investigated by using Am 241 , Co 57 , Cs 137 , Co 60 gamma-rays and 49–157 keV X-rays.

This paper is concerned with the double diffusive convection due to the melting of an ice plate into a calcium chloride aqueous solution inside a rectangular cavity. It is mainly considered the effect of the cavity inclination θ on the melting rate and the mean melting Nusselt- and Sherwood-numbers, experimentally as well as numerically. The ice plate melts spontaneously with decreasing temperature at the melting front even if initially there does not exist a temperature difference between the ice and the liquid. The concentration- and temperature-gradients near the melting front induce double diffusive convection in the liquid, which will affect the melting rate. Experiments reveal that the mean melting mass increases monotonically with increasing cavity inclination. The numerical analysis based on the laminar assumption predicts well the melting mass in the range of θ=0–90°, however, under-predicts the melting mass in the range of θ=90–180° as compared with the experimental results.

The neural network was applied to the estimation of catalyst deactivation by taking, as an example, methanol conversion into hydrocarbons over ion-exchanged dealuminated mordenites. In the first series, it was attempted to estimate the deactivation rate constant, kd defined in −dA/dt = kdA where A is the degree of conversion, from the amount of strong acid sites and the catalyst composition such as the Si/Al ratio and the degree of ion exchange. The estimated rate constant agreed well in most cases with the experimentally obtained constant. The most serious exception was Ba ion-exchanged dealuminated mordenite which experimentally exhibited the slowest deactivation. Better agreement was obtained when the first-order reaction rate constant was used as A in the above equation instead of the degree of conversion. In the second series, it was shown that the neural network has a strong ability to extrapolate the catalyst decay curve even without knowing catalyst composition and properties, especially when the first-order reaction rate constant was used to represent the catalyst activity. All of these results clearly demonstrate that the neural network is a powerful tool to estimate the deactivation behaviour of catalysts.

The biomechanics of using a walker for the partial weight bearing gait and as a method for gradually increasing the muscle activation level were examined with a force plate and surface electromyography. The results showed that the weight bearing force during gait with a walker is determined by the flexion angle of the hip joint. The value remains constant for each stride, indicating that a walker can be used for the partial weight bearing gait. Moreover, the muscle activation levels in the rectus femoris muscle and biceps femoris muscle per unit time during normal gait and gait with a walker with varying hip joint flexion angles were found to be correlated with the weight bearing force and to be constant for each stride. In addition, the muscle activation level was consistent with the level observed during the open kinetic chain resistance exercise with a specific loading level. These findings suggest that normal gait and gait with a walker may be applicable as a method for gradually increasing the muscle activation level.

Cellular structured activated carbon samples were prepared with the aid of alkali carbonates X2CO3 (X = Li, Na, K, Rb, or Cs) from dry bread yeast with a milling procedure. The resultant carbon possesses a very large adsorption amount even for supercritical methane. The activation with Cs2CO3 gave the greatest surface area of 2420 m2 g−1 from the subtracting pore effect method. The activation efficiency of X2CO3 (X = Li, Na, K, Rb, and Cs) was associated with the order of Gibbs free energy of X2O (X = Li, Na, K, Rb, and Cs) which should play an important role in the gasification. The carbon activated with Rb2CO3 gave the greatest adsorption amount of supercritical methane of 90 mg g−1 at 0.9 MPa at 303 K.

Pyrophylite is a porous material composed of the same constituent substances as bentonite, which is widely employed as a shield against high-level radiation leakage. However, as these materials allow a seepage of water, special attention is required when they are actually used for this purpose. One method that has been considered for preventing water seepage is the application of electrostatic force [1]. As a preparatory step of research, the authors have conducted experiments into the properties of the streaming current generated by the passage of water through the material. All air was extracted from the material by means of a vacuum pump, and the streaming current was measured. It was found to be positive. However, a repetition of the same experiment without the extraction of air yielded a negative polarity. The ζ potential of pyrophylite particles is −25 mV [2]. In general, streaming current usually displays the same polarity as ζ potential. From this point of view, the phenomenon of polarity change appearing when the air is extracted seems difficult to account for. In the discussion part of this paper, an attempt is made to explain the phenomenon using SEM photographs and the Poisson-Boltzmann equation.

New anthracycline antibiotics, designated as obelmycins A, D, E, F and G, were isolated from the culture broth of a variant strain of beta-rhodomycin-producing Streptomyces violaceus A262, identified as beta-isorhodomycinone glycosides and gamma-isorhodomycinone glycosides and assayed for their in vitro cytotoxicities against murine leukemic L1210 cell culture and the antimicrobial activities in comparison with some known anthracyclines.

We performed electron acceleration experiment with PW‐class laser and a plasma tube, which was created by imploding a hollow polystyrene cylinder. In this experiment, electron energies in excess of 600 MeV have been observed. Moreover, the spectra of a comparatively high‐density plasma ∼1019 cm−3 had a bump around 10 MeV. Additionally, we performed the absolute sensitivity calibration of imaging plate for 1 GeV electrons from the injector Linac of Spring‐8 in order to evaluate absolute number of GeV‐class electrons in the laser acceleration experiment.

A method based on frequency characteristics to distinguish partial discharge (PD) source in oil filled transformer is proposed. Frequency spectrum of electromagnetic wave from two typical PD sources, i.e., protrusion of metal and air void in oil was investigated. It was found that metal protrusion gave PD signal with stronger component in the frequency range above several hundreds MHz compared with air void. Since the acquisition of frequency spectrum is difficult in practical transformer test condition, we tried to apply the two frequency correlation method to distinguish the two PD sources. In the method, intensity of two frequency components of each PD signal is plotted on the x-y plane, where the horizontal axis represents the intensity of low frequency band and vertical axis represents that of high frequency band, which is a method to characterize a PD source on the x-y plane. The two PD sources were plotted clearly on the different area of the two frequency correlation graph, that is, metal protrusion yielded PD signal with higher frequency component than air void. We concluded that the method is effective to identify the PD source in oil filled transformer.

The experimental positioning of a flexible arm by a human operator is described. The flexible arm is characterized by nonlinearity and infinite degrees of freedom. The human operator interprets a given task and finds a procedure for the operation, devising an effective way of achieving the goal, based on his or her experience and knowledge about the task. The question of how these results can be modeled and applied to automatic control systems is considered, and the use of a reference input filter is proposed. The filter gives a satisfactory overall response if the time constant is chosen appropriately. >

We report a theoretical study on the optical properties of a small, water-soluble photosensory receptor, photoactive yellow protein (PYP). A hierarchical ab initio molecular orbital calculation accurately evaluated the optical absorption maximum of the wild-type, as well as the lambda(max) values of 12 mutants. Electronic excitation of the chromophore directly affects the electronic state of nearby atoms in the protein environment. This effect is explicitly considered in the present study. Furthermore, the spectral tuning mechanism of PYP was investigated at the atomic level. The static disorder of a protein molecule is intimately related to the complex nature of its energy landscape. By using molecular dynamics simulation and quantum mechanical structure optimization, we obtained multiple minimum energy conformations of PYP. The statistical distribution of electronic excitation energies of these minima was compared with the hole-burning experiment (Masciangioli, T. [2000] Photochem. Photobiol. 72, 639), a direct observation of the distribution of excitation energies.

Assuming that IFOVs of most mixels in a remote sensing image lie on landcover boundaries, in order to estimate landcover proportion high contrasted edges in a mixel IFOV can be approximately considered to locate an edge in a mixel very precisely. A precise edge locator which is based on the moment preserving principle is tested in computer experiments in order to estimate landcover proportion in a mixel in this research. The experiments show that: 1) the estimated landcover proportions were affected by the length of the edges, the noise, the window sizes of the locator and the PSF, 2) the magnitude of errors on long and high contrasted straight edges is almost smaller than 20%, 3) some improvements of the algorithm to estimate landcover proportion in mixels are necessary. >

Previously, the authors have analysed a model of the electrical double layer, demonstrating the positiveness of the /spl zeta/ potential arising when aluminium particles are introduced into distilled water. Further, they demonstrated that an increase in conductivity led to the appearance of a negative /spl zeta/ potential. The same type of phenomenon can be found when electrostatic potential energies are analysed by applying the Poisson-Boltzmann equation. The present paper provides a comparison of these two double layer models obtained from experimental measurements and from calculation respectively. From the comparison, a value of 5.3/spl times/10/sup -11/ m/sup 2//s is deduced for the coefficient of molecular diffusion. This is close to the value of 7.35/spl times/10/sup -11/ m/sup 2//s given by the Chemical Handbook for polyethylene oxide.

Field emission current from synthesized diamond can be increased by hydrogen plasma treatment. On the other hand, oxygen or oxygen-contained plasma treatment drastically decreases the field emission current. These are applicable to diamond grown on various substrates. A relation between field emission and the electrical conducting layer at diamond surface is suggested.

Dismantling and demolition of a nuclear power plant generates a large amount of metal waste. Recycling of such waste for resource is important because of the limited capacity of the disposal site. Authors have developed metal recycling processes. It is found that pyrometallurgical separation techniques can effectively separate nickel and cobalt, which contain main contributors of radioactivity, from iron and chromium.

A new anti-ulcer agent, ecabet sodium, is active against Helicobacter pylori.To assess the efficacy of ecabet sodium for the eradication of H. pylori in patients with gastroduodenal diseases.In a prospective, randomized and controlled study, patients infected with H. pylori were assigned to one of the following two groups: group LA, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. after meals for 2 weeks, and group LAE, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. + ecabet sodium 1000 mg b.d. after meals for 2 weeks. H. pylori status was determined before and at least 4 weeks after the therapy by rapid urease test, histology and a urea breath test.Of 101 patients (mean age 53 years, range 17-77 years, M/F: 68/33) enrolled in the study, 97 patients completed the protocol. Four patients were withdrawn because of diarrhoea (three from group LA) and skin rash (one from group LAE). The eradication of H. pylori was achieved in 28/48 (58%) patients in group LA and 38/49 (78%) patients in group LAE. The rate of eradication of H. pylori produced by the LAE treatment was significantly higher than that produced by the LA treatment. Side-effects appeared in two patients (malaise 1, skin rash 1) in group LAE and in seven patients (diarrhoea 6, dizziness 1) in group LA. These side effects disappeared spontaneously with cessation of the treatment.Ecabet sodium in combination with lansoprazole and amoxycillin increased the rate of eradication of H. pylori. Ecabet sodium appeared to reduce the incidence of diarrhoea as a side-effect of the dual LA therapy.

1. ABSTRACT The authors of this paper have previously developed a vacuum filtration technique for the manufacture of functionally graded materials (FGMs) by a progressive lamination method. For this, they have been granted a U. S. patent. Using this method, it is possible to manufacture FGMs with thicknesses ranging from several millimetres to several centimetres. The authors have already produced an iron (III) oxide-kaolin FGM, the graded condition of which they have verified by means of a scanning electron microscope. In addition, they have performed measurements to determine this material’s electrical properties viz: conductivity, relative permittivity and magnetic permeability. The present paper reports an experiment to create a different type of FGM, characterised by graded permittivity. The constituent materials used are titanium oxide and kaolin. The graded condition of manufactured specimens was investigated by mean of scanning electron microscope photographs and measurements of relative permittivity. Relative permittivity was found to vary between 2 and 5, while the photographs confirmed that the specimens were smoothly graded. On the basis of these results, it seems probable that graded permittivity elements can be manufactured using the authors’ method.

Recently, with advances in technology, materials for the construction of machinery are now being utilized in various kinds of severe environment. It is in order to cope with difficulties of this kind that recourse to “functionally graded materials” (FGMs) has been proposed in Japan. However, although various techniques are currently available for the manufacture of FGMs, it is very difficult to produce FGMs of the greater thickness widely required in manufacturing industry. This paper attempts to present a method of production for FGMs by means of an expression operation resulting in a mechanical separation of solids and liquids, using the two processes vacuum filtration and expression consolidation. It examines how this expression technology can be used to produce FGMs of greater thickness more simply and cheaply than has hitherto been possible. In this way, compressed FGM cakes materials could be manufactured using ZrO 2 as the ceramic material and stainless steel powder as the metallic material. FGM cakes produced in this way were air dried and then baked in an electrically powered reducing furnace. FGM cakes produced in the above described way observed the case that it use an addition agent and an effect of the graded layer steps and an effect by the thickness of it.

We report on structural, magnetic, and magnetoelectric (ME) properties of a U-type hexaferrite Sr 4 Co 2 Fe 36O 60 prepared by solid state reaction. Samples sintered at 1150-1180 °C in oxygen contain the fewest impurity phases and show highly insulating behavior. Powder neutron diffraction results reveal that a commensurate magnetic order with a (0,0,3/2) propagation vector develops below TN2 ?350 K. Corresponding to the appearance of the magnetic order, the sample shows a small ME effect. These results suggest that Sr 4 Co 2 Fe 36 O 60 is a room-temperature ME material in which the origin of the ME effect is similar to those of other ME hexaferrites.

Nonthermal acceleration of relativistic electrons is investigated with an intensive laser pulse. An energy distribution function of energetic particles in the universe or cosmic rays is well represented by a power-law spectrum, therefore, nonthermal acceleration is essential to understand the origin of cosmic rays. A possible candidate for the origin of cosmic rays is wakefield acceleration at relativistic astrophysical perpendicular shocks. The wakefield is considered to be excited by large-amplitude precursor light waves in the upstream of the shocks. Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma. An intensive laser pulse was propagated in a plasma tube created by imploding a hollow polystyrene cylinder, as the large amplitude light waves propagated in the upstream plasma at an astrophysical shock. Nonthermal electrons were generated, and the energy distribution functions of the electrons have a power-law component with an index of ~2. We described the detailed procedures to obtain the nonthermal components from data obtained by an electron spectrometer.

A 74-year-old male who had been infected with pulmonary tuberculosis since 1938 underwent thoracoplasty in 1955. After the operation, no symptoms manifested until 1988 when he developed hemosputum and hemoptysis in association with a cold with fever. Although he was admitted to a hospital, the symptoms could not be controlled, so he was referred to our department. The lesion causing the hemorrhage was considered to be in the upper lobe of the left lung. However, it would have been difficult to preserve respiratory function in the case of left upper lobectomy, because he had already undergone thoracoplasty on the right side. Therefore, bronchial artery embolization (BAE) using Spongel was performed. Second embolization was performed because hemoptysis referred after one month. However, the hemoptysis recurred again, so that two branches of the left subclavian artery and the left internal thoracic artery were ligated. No hemoptysis and hemosputum occurred for a while, but 2 years and 9 months after the operation, the patient was admitted due to hemoptysis with fever and coughing. Since the bronchial artery was embolized twice with spongel and twice with platinum coil, the patient's course has been good for 5 months.

One schizophrenic and two manic-depressive patients who after the administration of zotepine, a new antipsychotic and antimanic drug, developed alopecia areata, a kind of autoimmune disease, are reported. They recovered following the discontinuation or decrease in the dose of zotepine. These three cases of alopecia areata suggest that the antipsychotic drugs may induce autoimmune disease through their neuropsychological effect.

Screening of neuroblastoma is commonly performed on 6-month-old infants; therefore, its discovery in children younger than that age is extremely rare. However, a 4-month-old boy with pectus excavatum was found to also have mediastinal neuroblastoma after close examination. This 7 kg child had no apparent symptoms, yet revealed an egg-sized shadow along the right atrium in the chest X-ray film, and along the right side of the vertebrae on CT. Due to the increase in the size of the tumor after two months of observation, we suspected malignant neurogenic tumor and performed a thoracotomy. With a right posterolateral thoracotomy we removed the dark-brown, elastic tumor measuring 6 x 4 x 3 cm and located along the right side of the vertebrae from III through VIII ribs. The origin was the thoracic sympathicus and the pathological diagnosis of the tumor was neuroblastoma with rosset formation. After conducting a post-operative chemotherapy (Jame's protocol), no evidence of recurrence was observed at 33 months after surgical treatment. We summarized the previously reported seven surgically treated cases of Stage I mediastinal neuroblastoma at less than 12 months of age. Among the 2500 pectus excavatum surgeries that have been held at our department, non has been found to have mediastinal neuroblastoma.

Anthracycline antibiotics 2-hydroxyaclacinomycins A and B were isolated and purified from the culture broth of a recombinant strain which was produced by protoplast fusion of two aclacinomycin-blocked mutants. 2-Hydroxyaclacinomycin B is a new compound for which chemical structure and the biological activity in vitro were determined. 2-Hydroxyaclacinomycins had a stronger antitumor activity against murine leukemic L1210 cells in mice than the parent antibiotic aclacinomycins.

The technique of protoplast fusion which optimized prototrophic recombination in aclacinomycin-producing Streptomyces galilaeus was studied and applied to the construction of new anthracycline analog-producing recombinant upon genetic cross of two specific mutants blocked in aclacinomycin biosynthesis. Thus, 2-hydroxyaclacinomycin-producing recombinant was obtained by the protoplast fusion.

Energetic electrons were generated by the interaction of a high-intensity laser pulse with a plasma preformed from a hollow plastic cylinder via laser-driven implosion. The spectra of a comparatively high-density plasma ∼1019 cm−3 had a bump around 10 MeV. Simple numerical calculations explained the spectra obtained in this experiment. This indicates that the plasma tube has sufficient potential to convert a Maxwellian spectrum to a comparatively narrow spectrum.

Energetic electrons were generated using a 3-mm-long plasma tube created by imploding a hollow polystyrene cylinder. The spectra of a comparatively high-density plasma ~1019cm−3 had a bump around 10 MeV. Moreover, electron energies in excess of 600 MeV have been observed. The results of numerical calculations indicate that the bump around 10 MeV is produced by multi-dephasing of accelerated electrons in the electron plasma wave.

6-Methoxy- epi PS-5 1 was stereoselectively synthesized via a bicyclic β-lactam from N-benzyloxycarbonylaminomalonate.

The stabilizing effect of the 6-methoxyl or 6-hydroxyl substituent on dehydropeptidase I sensitivity of PS 5 was examined by a new total synthesis of 6-methoxy-epi-PS 5 and 6-hydroxy-epi-PS 5 from dimethyl benzyloxycarbonylaminomalonate. The Wittig reaction of α-(t-butoxycarbonyl)propylidenetriphenylphosphorane with a pyrrolidine derivative predominantly afforded a trans-α,β unsaturated ester, which was epoxidated, N-deprotected and cyclized to give a bicyclic carbapenam with a C-6 hydroxyl group. After the 6-hydroxyl group was methylated, the 2-(acetamido)ethylthio side chain was introduced at C-3 of the carbapenam by benzeneselenenylation of the geminal diester, followed by elimination of the seleninyl group. The resulting carbapenam was converted to 6-methoxy-epi-PS 5. Furthermore, 6-hydroxy-epi-PS 5 was synthesized by the use of tetrahydropyranyl and trimethylsilyl ethers for protection of the 6-hydroxyl group in a process similar to that for synthesis of 6-methoxy-epi-PS 5.

The new macrolide antibiotics were isolated by silica gel chromatography. They showed a UV absorption maximum at 240 nm. Deltamycins A1, A2 and A3 were demonstrated to be new macrolide antibiotics on the basis of their physicochemical properties whereas deltamycin A4 was identified as carbomycin A.