Search

Introduction Lateral radiography of the knee joint is frequently performed; however, the retake rate is high owing to positioning errors. Therefore, in this study, to reduce the required number and time of image retakes, we developed a system that can classify the tilting directions of lateral knee radiographs and evaluated the accuracy of the proposed method. Methods Using our system, the tilting directions of a lateral knee radiographs were classified into four direction categories. The system was developed by training the DCNN based on 50 cases of Raysum images and tested on three types test dataset; ten more cases of Raysum images, one case of flexed knee joint phantom images and 14 rejected knee joint radiographs. To train a deep convolutional neural network (DCNN), we employed Raysum images created via three-dimensional (3D) X-ray computed tomography (CT); 11 520 Raysum images were created from 60 cases of 3D CT data by changing the projection angles. Thereby, we obtained pseudo images attached with correct labels that are essential for training. Results The overall accuracy on each test dataset was 88.5 ± 7.0% (mean ± standard deviation), 81.4 ± 11.2%, and 73.3 ± 9.2%. The larger the tilting degree of the knee joint, the higher the classification accuracy. Conclusion DCNN could classify the tilting directions of a knee joint from lateral knee radiographs. Using Raysum images made it possible to facilitate creating dataset for training DCNN. The possibility was indicated for using support system of lateral knee radiographs. Implications for practice The system may also reduce the burden on patients and increase the work efficiency of radiological technologists.

The free energy landscape (FEL) depends on temperature by its definition and the FEL is reorganized with time delay when the temperature is modulated. We investigate how the relaxation of the FEL manifests itself in physical properties. Exploiting a simple two-level model for the dielectric relaxation, we first show that the relaxation of the FEL produces time dependence of the relaxation time of the dielectric response. Then we discuss the relaxation of dielectric susceptibility when the temperature is suddenly increased/decreased and show that the susceptibility relaxes to the equilibrium value with the same relaxation time as the FEL in the long time limit. In order to show the general feature of the temperature modulation spectroscopy, we consider the dynamics of an order parameter of the Landau model which has a delayed response to the temperature modulation with relaxation time. When the temperature is modulated sinusoidally, we show that there appear second order responses at the sum and the difference of the frequencies of the external field and the temperature modulation and that the relaxation time of the FEL can be deduced from these two responses.

An electromagnetic calorimeter complex, FOREST, has been constructed for meson photoproduction experiments at the Research Center for Electron Photon Science, Tohoku University. It consists of three types of calorimeters, which are made of pure cesium-iodide crystals, lead scintillating-fiber modules, and lead glass Cherenkov counters. Each calorimeter is equipped with a plastic scintillator hodoscope to identify charged particles. The design and performance of FOREST are described. The energy responses of test calorimeters have been investigated by using 100–800 MeV positron beams. The energy resolutions of the three calorimeters are found to be approximately 3%, 7%, and 5% for 1-GeV photons, respectively. A cryogenic hydrogen/deuterium target system fitted to the FOREST experiments and a newly developed data acquisition system are also presented.

We present a real-time supernova neutrino burst monitor at Super-Kamiokande (SK). Detecting supernova explosions by neutrinos in real time is crucial for giving a clear picture of the explosion mechanism. Since the neutrinos are expected to come earlier than light, a fast broadcasting of the detection may give astronomers a chance to make electromagnetic radiation observations of the explosions right at the onset. The role of the monitor includes a fast announcement of the neutrino burst detection to the world and a determination of the supernova direction. We present the online neutrino burst detection system and studies of the direction determination accuracy based on simulations at SK., 15 pages, 8 figures, accepted for publication in Astroparticle Physics

A fast beam-profile monitor has been developed for high-energy photon beamlines at the Research Center for Electron Photon Science, Tohoku University. The position of the photon converted into an electron–positron pair in a 0.5 mm-thick aluminum plate is measured with two hodoscopes made of scintillating fibers with cross-sections of 3 × 3 mm 2 . Events in which charged particles are produced upstream are rejected with a charge veto plastic scintillator placed in front of the plate, and pair-production events are identified with a trigger plastic scintillator placed behind the plate. The position is determined by a developed logic module with a field-programmable gate array. The dead time for processing an event is 35 ns, and a high data acquisition efficiency ( ~ 100 % ) can be achieved with this monitor for high-intensity photon beams corresponding to 20 MHz tagging signals.

Immunohistochemical and ex vivo anatomical studies have provided many glimpses of the variety, distribution, and signaling components of vertebrate retinal neurons. The beauty of numerous images published to date, and the qualitative and quantitative information they provide, indicate that these approaches are fundamentally useful. However, obtaining these images entailed tissue handling and exposure to chemical solutions that differ from normal extracellular fluid in composition, temperature, and osmolarity. Because the differences are large enough to alter intercellular and intracellular signaling in neurons, and because retinae are susceptible to crush, shear, and fray, it is natural to wonder if immunohistochemical and anatomical methods disturb or damage the cells they are designed to examine. Tissue fixation is typically incorporated to guard against this damage and is therefore critically important to the quality and significance of the harvested data. Here, we describe mechanisms of fixation; advantages and disadvantages of using formaldehyde and glutaraldehyde as fixatives during immunohistochemistry; and modifications of widely used protocols that have recently been found to improve cell shape preservation and immunostaining patterns, especially in proximal retinal neurons.

The mechanically induced phase transformation (MIPT), from austenitic phase to martensitic phase, has been regarded to affect the mechanical behavior of materials, including fracture properties of steels such as the ductility, the toughness, etc. The understanding of the MIPT effect, of the so-called retained austenite, on the mechanical behavior under general loading condition is still challenging topics to be solved. In the present paper the MIPT effect of retained austenite to the martensitic phase stress and strain distribution is numerically examined by a Finite Element Analysis based on the crystal plasticity theory incorporating the MIPT.

A search for Supernova Relic Neutrinos $\bar{\nu}_e$'s is first conducted via inverse-beta-decay by tagging neutron capture on hydrogen at Super-Kamiokande-IV. The neutron tagging efficiency is determined to be $(17.74\pm0.04_{stat.}\pm1.05_{sys.})%$, while the corresponding accidental background probability is $(1.06\pm0.01_{stat.}\pm 0.18_{sys.})$%. Using 960 days of data, we obtain 13 inverse-beta-decay candidates in the range of $E_{\bar{\nu}_e}$ between 13.3 MeV and 31.3 MeV. All of the observed candidates are attributed to background. Upper limits at 90% C.L. are calculated in the absence of a signal., Comment: 6 pages, 4 figures

This study aims at helping optimize the application of deicing agents on the winter road surface. In this regard, field tests were conducted for observing how water and deicing agents (= salt) disperse due to passing vehicles as well as for calculating the dissolution rates of salt on the road surface. Additionally, we developed a one-dimensional time-dependent model for the prediction of freezing on a road surface. It takes into account the effects of salting and passing vehicles and is called the RSF-SV model. Its validity was examined by using field test results. Based on the test results, the relationship between the amount of water dispersed due to passing vehicles and the thickness of the water film on the surface was formulated, and the dissolution rate of salt on the icy road surface was identified. The RSF-SV model used these results for successfully reproducing the time-series changes in the surface temperature, the ice film thickness, the water film thickness, the salt concentration, and the amount of residual salt on the ice-covered road surface after the application of deicing agents.

Thermochemical two-step water splitting cycle by concentrated solar heat has been studied as an energy conversion of solar energy into hydrogen energy. The thermochemical two-step water splitting cycle using metal oxide redox pair was composed of thermal reduction (T-R) step of metal oxide at higher temperature to release oxygen and, subsequent water decomposition (W-D) step of the reduced metal oxide with steam at lower temperature to produce hydrogen. Recently, cerium oxide (CeO2) is concerned as a redox pair of the thermochemical cycle for highly reactivity and cyclicity at high temperature. In this study, we focused a kinetic analysis of thermochemical two-step water splitting using cerium oxide. Various theoretical reaction models for thermal reduction (T-R) step of CeO2 particles are examined, and the appropriate reaction model for experimental results of thermogravimetric analysis was found by Master plot method. Finally, the reaction rate equation of thermal reduction is estimated.

Background Immune-checkpoint inhibitors (ICI) have recently been used in many types of cancers including non-small cell lung cancer (NSCLC). Interstitial lung disease associated with ICI (ICI-ILD) is a serious immune-related adverse event. However, comprehensive clinical characterization of ICI-ILD is still lacking. Methods We retrospectively analyzed clinical and imaging data of all consecutive ICI treated patients in Kurashiki Central Hospital (Okayama, Japan) between January 2016 and March 2019. We elucidated clinical characteristics, radiopathological patterns, therapeutic strategies and outcomes of ICI-ILD and analyzed the prognostic factor of ICI-ILD. Results Among 316 (222 NSCLC and 94 non-NSCLC) treated with ICI, 35 (11.1%) were diagnosed as ICI-ILD. Of those, NSCLC/gastric cancer/urinary cancer/head and neck cancer/malignant lymphoma were 26/2/2/4/1, respectively: mean age was 69.3 ± 9.0 years; 29 (82.9%) were men; 19 (54.3%) received Nivolumab monotherapy and 10 (28.6%) received Pembrolizumab monotherapy; Best objective response rate until ICI-ILD diagnosis was 48.6% (11/35); The median time (range) from ICI introduction to ICI-ILD was 57 (22-155) days. CTCAE grade 1/2/3 + 4/5 was 10 (28.6%)/14 (40.0%)/7 (20.0%)/4 (11.4%), respectively; Organizing pneumonia was found in 57.1% (20/35) in CT and 66.7% (4/6) in transbronchial lung biopsy; Lymphocyte differential count of bronchoalveolar lavage fluid (range) was 41 (33-60) %; 26 (74.3%) were treated with corticosteroid; 29 (82.9%) had ICI-ILD improved but 6 (17.1%) did not. The median survival time was significantly different between ILD improved group and non-improved group (17.1 months vs 0.8 months, p Conclusions In our real-world experience, half of ICI-ILD patients had a response toward malignancy. Organizing pneumonia was the most common radiopathological pattern and lymphocyte differential count of bronchoalveolar lavage fluid was elevated in ICI-ILD. If ICI-ILD does not improve, its prognosis may be very poor. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

Warfarin, a coumarin rodenticide, is commonly used worldwide for rodent control, and is often reported as the cause for poisoning accidents in nontarget animals, in particular bird species. However, the metabolism of warfarin in birds is still unclear. In a previous study, we found an unknown warfarin metabolite in chicken cytosolic fractions. In the present study, we aimed to clarify the cytosolic warfarin metabolites in chickens compared with those in rats. The cytosol fractions of both chicken and rat livers showed the metabolic activity of 2 diastereomers and 2 enantiomers of warfarin alcohol. In chicken cytosol, we found that the production level of (S)-warfarin-(S)-alcohol was markedly higher (32-fold) than that in rat cytosol. From the results of the inhibition assay, we finally suggest that aldehyde oxidase may mainly contribute to the warfarin alcohol products in chicken cytosol.

The second GeV bremsstrahlung photon beamline has been constructed for meson photo-production experiments at Research Center for Electron Photon Science, Tohoku University, where a 1200 MeV electron synchrotron called STretcher Booster (STB) has been in operation primarily for Quark Nuclear Physics. An internal radiator is employed to produce the bremsstrahlung photon beam out of circulating electrons in the STB ring. A photon tagging system is placed inside one of the bending magnets of the ring. The tagged energy of the photon beam ranges from 740 to 1150 MeV for 1200 MeV operation of the STB synchrotron. The details of the tagging system and the characteristics of the photon beam are described.

Iodine substituted 2,5-di(1,3-dithiol-2-ylidene)-1,3-dithiolan-4-thione and —one derivatives, namely 2-[4,5-bis(ethylsulfanyl)-1,3-dithiole-2-ylidene]-5-(4,5-diiodo-1,3- dithiol-2-ylidene)-1,3-dithiolan-4-thione (1a) and -one (1b), were synthesized. The 1a was obtained from the reaction of bis(tetraethylammonium)bis[2-[4,5-bis(ethylsulfanyl)-1,3- dithiol-2-ylidene]-1,3-dithiole-4,5-bis(thiolato)]zinc and 4,5-diiodo-2-methylsulfanyl-1,3- dithiole-2-ylium tetrafluoroborate. The 1b was obtained from the reaction of 1a and mercury(II) acetate. Recrystallization of 1a and 1b from carbondisulfide/n-hexane gave single crystals suitable for X-ray structure analysis. In the crystals, both 1a and 1b were stacked to form one-dimensional columns and the interplanar distances in the columns were greater than a π-cloud thickness. Some effective side-by-side contacts were observed between molecules of adjacent columns. The interactions were accomplished through S…I contacts for 1a, and S…I and O…I contacts for 1b. The interesting features of these structures are the intermolecular CS…I contacts for 1a and the intermolecular CO…I contacts for 1b which are respectively, 16% and 17%, shorter than the sum of van der Waals radii of corresponding atoms. DFT calculations suggest that the effective geometry of 1a molecules for charge transfer from the moiety interacting with sulfur to the moiety interacting with iodine plays an important role for molecular packing in the crystal system.

In general, closer proximity of embedded SiGe (eSiGe) source drain (S/D) structure to the channel improves p-channel metal oxide semiconductor field-effect transistor (pMOSFET) performance because of the higher stress in the channel. However, we found the critical optimization methodology which has a relation between boron diffusion modulation in SiGe and short channel effect (SCE) in the context of the eSiGe proximity change. Therefore, additional source drain extension (SDE) optimization is required to improve device performance with closer eSiGe proximity focusing on the parasitic resistance reduction. As a result of the optimization, we have demonstrated high drive current of 755 μA/μm at V dd = 1.0 V, I OFF = 100 nA/μm, 30 nm gate length pMOSFET.

This study was conducted to investigate the effects of injection of vitamins C (VC) and E (VE) into broodstock on the vitamin levels of broodstock and eggs and subsequent egg and larval quality in the Japanese eel. Broodstock were allotted to one of three groups; control group, injected with physiological saline; early group, injected with vitamins during the early part of maturation (1st–3rd weeks after initiation of maturation induction); later group, injected with vitamins during the later part of maturation (4th–6th weeks after initiation of maturation induction). Broodstock were injected with an emulsion of VC and VE at the same time as an injection of salmon pituitary extract during the induction of maturation. The emulsion was prepared by mixing α-tocopherol, sodium ascorbate, an emulsifier, and water just before injection. The levels of both vitamins in eggs and broodstock increased following vitamin injection. However, the accumulation of vitamins in broodstock and eggs was higher for VE than for VC. Hatching rate, survival and normality of larvae increased with vitamin treatments. The results of this study showed that VC and VE injection into broodstock during artificial maturation increases the vitamin content of eggs and can improve egg quality in Japanese eel.

DI-BSCCO, the commercial BSCCO tapes produced by Sumitomo Electric with the controlled-overpressure sintering technique, has been progressing in the performance for increasing expansion of high temperature superconducting applications. Type H as the most common product has recorded 218 A as the highest critical current in 77 K, self-field, which is corresponding to 500 A per 1 cm width. Now it can provide both long-length and uniform high critical current up to 180 A as commercial products. Type S offers high overall critical current density similar to Type H and half cross-sectional area and the narrower width around 2.5 mm. It gives low price and compact size as a benefit to the applications operated with the relatively smaller current. Type AC offers low AC loss which is produced by application of the narrow width similar to Type S and twisted multi-filaments. All the products have achieved long-length more than 1 km and uniform critical currents over the entire length of the tapes. Mechanical toughness comes from metallic tape lamination technique applicable to all DI-BSCCO family as an optional extra. A 3-ply tape of one Type H and two thin stainless steel tapes provides high rated tensile stress more than 300 MPa and high current density more than 13 kA/cm2 in 77 K. Alternative brass or copper laminated tape brings about lower electric resistance under overload current. It is possible to produce an order-made tape under consultation, which exhibits excellent manifold abilities on critical current, AC property as well as mechanical properties.

We performed a round robin test to measure AC losses in Bi-2223 Ag-sheathed tapes with saddle-shaped pickup coils in an alternating perpendicular magnetic field at liquid nitrogen temperature. Two laboratories participated in the round robin test with each system of the pickup coil and the measurement circuit. Short specimens of a Bi-2223 tape and a copper magnet to generate the alternating magnetic field were used for common conditions in the test. The saddle-shaped pickup coils were made under recommended conditions for the structure and the sizes that give a calibration coefficient around unity. The signals of the magnetic moment from the pickup coils were calibrated by using a standard hairpin copper tape. AC losses of the common specimen of the Bi-2223 tape were measured in the round robin test in the ranges of frequency up to 60 Hz and the amplitude up to 0.2 T of perpendicular magnetic field. While we had only two participants in the test, we obtained the following results in a pre-standardization process of the AC loss measurement with the saddle-shaped pickup coil (i) it was suggested from the calibration procedure using hairpin copper tape that the deviations from numerical simulation for an ideal pickup coil and a sufficiently long specimen is within 3% on an average, (ii) the values of COV for the AC losses measured at 1 Hz and 10 Hz are less than about 3% in the range of the field amplitude between 0.02 T and 0.2 T.

Solving the time-dependent Ginzburg–Landau equation with the finite element method, we discussed the vortex dynamics in superconducting networks. We show that in the asymmetric networks, the current driven vortex dynamics becomes asymmetric, and therefore rectifying the vortex motion may be possible.

A subset of neutrino-induced upward through-going muons in the Super-Kamiokande detector consists of high energy muons which lose energy through radiative processes such as bremsstrahlung, e^{+} e^{-} pair production and photonuclear interactions. These ``upward showering muons'' comprise an event sample whose mean parent neutrino energy is approximately 1 TeV. We show that the zenith angle distribution of upward showering muons is consistent with negligible distortion due to neutrino oscillations, as expected of such a high-energy neutrino sample. We present astronomical searches using these high energy events, such as those from WIMP annihilations in the Sun, Earth and Galactic Center, some suspected point sources, as well as searches for diffuse flux from the interstellar medium., Comment: Submitted for publication to Astroparticle Physics. Fig 12 has slightly higher resolution in the version submitted to the journal

We investigated the flow properties of mixed solvents of water and N , N -dimethylformamide (DMF) through poly( N -isopropylacrylamide) (PNIPA) gel membranes. The swelling behavior of the gels in the mixed solvents with various compositions was also examined. A simple model to describe the swelling and solvent flow properties for a polymer gel/mixed solvent system was presented. In the swelling measurements, the composition dependence of the degree of swelling ( Θ ) of the PNIPA gels showed a minimum at the DMF fraction ( φ ′ DMF ) of 0.6. In the solvent flow experiments, pressure gradient acting between two solvent–gel interfaces caused the permeation of the mixed solvents through the gel membranes. Little change in solvent composition by the permeation occurred. The integrated flow rate ( F ) over time ( t ) monotonously increased with increasing t . The slope of F versus t curves becomes constant at long times. The inverse of the frictional coefficients for the steady flow plotted against solvent composition is quite similar in shape to the Θ curve. This indicates that the degree of the swelling greatly affects the flow rate of the solvents in the gels.

A novel SiGe-S/D structure for high performance pMOSFET called two-step recessed SiGe-source/drain (S/D) is developed with careful optimization of recessed SiGe-S/D structure. With this method, hole mobility, short channel effect and S/D resistance in pMOSFET are improved compared with conventional recessed SiGe-S/D structure. To enhance device performance such as drain current drivability, SiGe region has to be closer to channel region. Then, conventional deep SiGe-S/D region with carefully optimized shallow SiGe SDE region showed additional device performance improvement without SCE degradation. As a result, high performance 24 nm gate length pMOSFET was demonstrated with drive current of 451 μA/μm at ∣ V dd ∣ of 0.9 V and I off of 100 nA/μm (552 μA/μm at ∣ V dd ∣ of 1.0 V). Furthermore, by combining with V dd scaling, we indicate the extendability of two-step recessed SiGe-S/D structure down to 15 nm node generation.

A neutron detector by using a metallic high- T c superconductor MgB 2 is based on an idea that an energy released by a nuclear reaction between neutron and 10 B leads to an instantaneous destruction of the superconducting state. Neutron can be detected as a voltage pulse caused by an instantaneous nucleated normal region. We investigate how a hot spot caused by a nuclear reaction diffuses in an MgB 2 detector both in a non-membrane type detector as well as in a membrane type detector. Numerical simulations of the heat transport equation have been carried out by means of the finite element method. We succeeded in generating a transient pulse signal from the MgB 2 detector.

We have investigated quasi-particle structure and superconducting state of the nano-scaled superconductor under an external magnetic field using a microscopic Bogoliubov–de Gennes equation. Our results show that the giant vortex state has a peak of local density of states at the center of the vortex core in negative energy, while the singly quantized vortex has it in positive energy. This may be observable for scanning tunneling spectroscopy experiments.

Solving the Bogoliubov–de Gennes equation for a tight-binding mean-field Hamiltonian with local superconducting order parameter, we investigate stable superconducting order parameter structures for anisotropic superconductors in nano-structures. Numerical results show that for a diamond-shaped d-wave superconductor symmetry is mainly s + id-wave, although other components, such as an anisotropic s-wave component, exist.

A d -dot is a nano-scaled superconducting composite structure, which is a d-wave superconducting dot embedded in an s-wave superconductor, and behaves as a 1/2 spin because it has spontaneous half-integer quantum fluxes around its corners. Solving the two-components Ginzburg–Landau equations for two equal square d -dot’s with various distances and directions between them, we investigated the interaction between two equal square d -dot’s. The results show the ferromagnetic configuration is more stable than the antiferromagnetic one at large distance and for all directions. But at small distance the antiferromagnetic configuration becomes more stable instead of the ferromagnetic configuration, when the dot size is small.

The specialized tritium-measuring system was developed. The amount of tritium production in tritium monitors (Li–Al alloy and LiAlO 2 pebble) irradiated in the JMTR was calculated by using the Monte Carlo code MCNP and was measured by using the measuring system. The amount of measured tritium values was 66.5–150 MBq per tritium monitor. Almost all the amount of tritium production in the tritium monitor was trapped by the measuring system. The ratios of calculated to measured amount of tritium productions was 0.99–1.08. The applicability of tritium monitors and the specialized tritium-measuring system for fusion blanket in-pile tests was confirmed by this study.

We formulate a canonical quantum theory for the square-shape closed 0–π junction system in the absence of an external magnetic field. When the quantum tunneling takes place between the two degenerate classical ground states having different current patterns, the system forms a quantum two-level system. The Hamiltonian which describes the quantum two-level system is derived from the generalized sine-Gordon equation.

The fracture properties of rare earth (yttrium, gadolinium, and samarium) doped ceria ceramics were systematically investigated using the modified small punch method at room temperature in air and at high temperatures in argon gas. The samples prepared by oxalate co-precipitation method showed higher fracture strength than those by solid-state reaction method. In addition, the sintering temperature dependence of gadolinium doped ceria indicated that the highest fracture strength was attained by sintering at 1600 °C. Furthermore, it turned out that the fracture strength was influenced by the dopant concentration rather than the kind of dopant. The relationship between mechanical properties and defect structures are discussed from the dopant concentration, sintering temperature and testing temperature dependence of the fracture strength.

The effect of strain path during severe plastic deformation via equal-channel angular pressing on grain refinement and structural features of a model Cu–Cr alloy is investigated in terms of grain shape, dimensions, preferred crystallographic orientation and distribution of grain boundaries with respect to the angle of misorientation. The mechanical behavior of differently processed specimens is assessed in both monotonic and cyclic tests aimed at clarification of the role played by different structural factors in the resultant mechanical properties. It is shown, that despite the considerable microstructural differences in the grain morphology and texture, the tensile and fatigue strength is only slightly affected by the processing routes chosen in the present study. However, the strain path and, therefore, the grain shape and texture have some effect on ductility and strain localization, which is particularly pronounced during cyclic loading.

A creep test was performed on yttria-doped ceria (YDC), which was investigated as an electrolyte for solid oxide fuel cells (SOFC). The test was performed using a four-point bending method and with testing conditions including a constant load under a temperature range of 1050–1125 °C, an applied stress of 20–50 MPa, and an oxygen partial pressure of P (O 2 )=0.21–10 −15.2 atm. The results showed that the creep rate increased with decreasing P (O 2 ), and showed a peak at P (O 2 )=10 −13.6 atm. The activation energy for creep was increased from 264 to 333 kJ/mol with decreasing P (O 2 ) from 0.21 to 10 −14.5 atm. These values were much higher than the reported activation energy of oxygen anion diffusion in ceria. Thus, it could be suggested that the creep mechanism is controlled by cation diffusion. The creep mechanism changed from Nabarro-Herring creep to grain boundary sliding in a reducing atmosphere when the P (O 2 ) was lower than 10 −14.5 atm.

We describe here methods for dissociating retinal ganglion cells from adult goldfish and rat without proteolytic enzymes, and show responses of ganglion cells isolated this way to step-wise voltage changes and fluctuating current injections. Taking advantage of the laminar organization of vertebrate retinas, photoreceptors and other cells were lifted away from the distal side of freshly isolated goldfish retinas, after contact with pieces of membrane filter. Likewise, cells were sliced away from the distal side of freshly isolated rat retinas, after these adhered to a membrane filter. The remaining portions of retina were incubated in an enzyme-free, low Ca2+ solution, and triturated. After aliquots of the resulting cell suspension were plated, ganglion cells could be identified by dye retrogradely transported via the optic nerve. These cells showed no obvious morphological degeneration for several days of culture. Perforated-patch whole-cell recordings showed that the goldfish ganglion cells spike tonically in response to depolarizing constant current injections, that these spikes are temporally precise in response to fluctuating current injections, and that the largest voltage-gated Na+ currents of these cells were larger than those of ganglion cells isolated with a neutral protease.

Mn 3s photoemission spectroscopy has been performed at 300 and 100 K for Pr 0.5 Ca 0.5 MnO 3− δ which undergoes a charge-ordering transition around 235 K with decreasing temperature. We have observed in the Mn 3s spectrum the change in the Mn valency of Pr 0.5 Ca 0.5 MnO 3− δ accompanied by the transition. The Mn 3s spectrum at 300 K for Pr 0.5 Ca 0.5 MnO 3− δ is nearly identical to that of La 1.2 Sr 1.8 Mn 2 O 7 in which the formal valence of the Mn ion is +3.4. This is consistent with the fact that the oxygen deficiency δ is 0.05 for the present sample. On the other hand the Mn 3s spectrum at 100 K is well reproduced by a superposition of those for LiMnO 2 with Mn 3+ and for SrMnO 3 with Mn 4+ , while the mean Mn valency at 100 K remains being +3.4. This indicates that the Mn ions in Pr 0.5 Ca 0.5 MnO 3− δ are in the two different valence states below the transition temperature.

Arsenic ions were implanted in a strained-Si/SiGe/Si hetero-structure to fabricate an n + layer in the substrate. The disordering of the substrate caused by ion implantation and the reordering during post-implant rapid thermal annealing (RTA) were analyzed by Rutherford backscattering and channeling (RBS) measurements. It was shown that the major part of implantation-induced defects was eliminated during RTA for 10 s above 900 °C. Electrical and atomic-concentration profiles for As-implanted layers were examined by differential Hall-effect and secondary ion mass spectrometric (SIMS) measurements, respectively. A 25-nm thick, n + layer with carrier concentrations in a range of 5.2×10 19 to 1.7×10 20 cm −3 was formed in the strained Si layer after RTA at 1000° C without the deterioration in the abruptness of the Si/SiGe interface. It was also revealed that the electrons in the strained Si layer had a higher mobility than the electrons in bulk Si by a factor of around 1.2 in a carrier concentration range of mid-10 19 to -10 20 cm −3 .

Strong enhancement of the Er-related 1.54 μm emission was obtained at room temperature from Er-doped porous silicon (PSi), when host PSi was slightly preoxidized at 900°C before Er incorporation. It was speculated that the formation of the oxide interlayer played an important role. Separate measurements of the energy transfer and the Auger deexcitation between carriers in Si crystallites and Er ions were carried out using a two-beam (cw and pulse) excitation method for various preoxidation time which was supposed to change the oxide interlayer thicknesses from about 1 to 10 nm . It was found that a very thin SiO2 interlayer between Si crystallites and Er ions suppressed preferentially the Auger deexcitation to the carrier-mediated Er excitation. A thin SiO2 interlayer was also effective to suppress the phonon-assisted energy backtransfer at high temperatures (so-called temperature quenching). This preferential suppression of the energy backflow (both Auger deexcitation and temperature quenching) by a thin oxide interlayer led to a strong room temperature Er-related emission at 1.54 μm in Er-doped porous silicon. The Er/SiO2/Si structure was also formed on a flat Si surface and quite the same result was obtained. The oxide interlayer thickness of ∼2 nm was found optimum to suppress the energy backflow sufficiently with only a slight decrease in the carrier-mediated excitation of Er ions.

The K2K long-baseline neutrino oscillation experiment uses a Scintillating Fiber Detector (SciFi) to reconstruct charged particles produced in neutrino interactions in the near detector. We describe the track reconstruction algorithm and the performance of the SciFi after three years of operation., Comment: 24pages,18 figures, and 1 table. Preprint submitted to NIM

K2K, a long-baseline neutrino-oscillation experiment between KEK PS and Super-Kamiokande (SK), employs two near-site neutrino detectors: a SK-like water Cherenkov detector and a detector complex of a scintillating fiber tracker and a muon range detector. In this talk I describe data of these front detectors in detail. The distributions of muons, a product of charged-current inclusive interactions of neutrinos via nuclei, νμ + N → μ + X, are shown in a comparison with our standard Monte Carlo simulation results.

We investigated the influence of vinylene carbonate, as an additive molecule, on the decomposition phenomena of electrolyte solution [ethylene carbonate (EC)—ethyl methyl carbonate (EMC) (1:2 by volume) containing 1 M LiPF6] on a highly oriented pyrolytic graphite (HOPG) negative electrode by using cyclic voltammetry (CV) and atomic force microscopy (AFM). Vinylene carbonate deactivated reactive sites (e.g. radicals and oxides at the defects and the edge of carbon layer) on the cleaved surface of the HOPG negative electrode, and prevented further decomposition of the other solvents there. Further, vinylene carbonate induced an ultra-thin film (less than 1.0 nm in thickness) on the terrace of the basal plane of the HOPG negative electrode, and this film suppressed the decomposition of electrolyte solution on the terraces of the basal plane. We consider that this ultra-thin passivating film is composed of a reduction product of vinylene carbonate (VC), and might have a polymer structure. These induced effects might explain how VC improves the life performance of lithium-ion cells.

Straight and zigzag quantum dot arrays (QDAs) are fabricated on GaAs/AlGaAs single heterostructures by using electron-beam lithography and wet-chemical etching. The magnetoresistance is measured at T=4.2 K . Low-field magnetoresistance shows several peaks whose magnetic-field position depends on the lateral shape of the QDAs. Numerical simulation of magnetoconductance characteristics is performed, and the results are compared with the experimental results.

Superconducting torque measurements for a Ba(Fe,Co) 2 As 2 iron arsenic superconductor have been carried out to obtain anisotropy in 1 kG at 10 K as well as in 10 kG at 22 K. We found that the anisotropy in penetration depth γ λ and the anisotropy in coherence length γ ξ in the multi-band Kogan analysis are modest or almost isotropic. Theoretical calculation suggests the anisotropy of carrier mass γ λ is approximated as 3 in BaFe 2 As 2 system. The γ λ value changes from 1 to 3 obtained by the torque analyses, and is in good agreement with the theoretical prediction. The torque curve was also analyzed by our new torque theory, which takes into account the vortex core contribution properly. We conclude that our Ba(Fe,Co) 2 As 2 single crystal is almost isotropic in marked contrast with high- T c cuprates.

The compact reversed shear tokamak, CREST, is a cost competitive power reactor concept based on the reversed shear high beta plasma. As the cooling system of CREST blanket, the direct superheated steam cycle is adopted to simplify the heat transport/power generation system and to achieve high thermal efficiency with a water cooled concept. Thermal-hydraulic design of the blanket was performed for the nominal operation, the start-up operation and the partial load operation. As a result of the study, it was confirmed that the direct steam cycle blanket is promising for a power reactor and is feasible not only at the nominal operation condition but also at the reactor start-up and the partial load conditions.

The KEK to Kamioka long-baseline neutrino experiment (K2K) has begun its investigation of neutrino oscillations suggested by atmospheric neutrino observations. Twenty-eight neutrino events have been detected in coincidence with the expected arrival time of the beam in the 22.5 kt fiducial volume of Super--Kamiokande, the far detector at 250 km distance. The expectation is 37.8+3.5-3.8, derived using measurements of neutrino interactions in a near detector and extrapolation using a beam simulation validated by a measurement of pion kinematics after production and focusing. The background is of order 10^-3 events., Comment: 6 pages, 3 embedded figures, LaTeX with RevTeX style, submitted to PRL. This version is As Submitted

Factors determining the low temperature fluorescent transition rate of the luminescence of rare earth implanted semiconductors are studied. Photocarrier induced Auger deexcitation has been used to separate the radiative transition rate from the fluorescent one for Er-, Er and Ne-, Er and O-implanted Si and Ho-implanted GaAs.

Distributions of plasma parameters, such as electron temperature and electron density have been studied for large-volume processing. In terms of precise study of large-volume plasma, ion-species distributions in plasma should be measured as well as those of plasma parameters. However, no method to measure the spatial distributions of ion species has been developed so far. In this study, we construct a new apparatus to measure the ion-species distribution by using a quadrupole mass spectrometer, which can be moved in vacuum perpendicularly to the beam extraction. Furthermore, we propose a new method to generate uniform plasma by introducing gas in pulse and generate pulsed plasma correspondently with the gas introduction. The results suggest that the ion-species distributions are not consistent with the electron-density distribution and spatial distributions of ion species can be improved by introducing gas in pulse and generating pulsed plasma. For further study towards the next-generation semiconductor fabrication, the ion-species distributions in large-volume plasma should be taken into account as well as those of the other plasma parameters.