Liquid crystal variable optical attenuators integrated on planarlightwave circuits

Variable optical attenuators using polymer-network liquid crystal have been integrated with the pitch of 250 μm on planar lightwave circuits. Trenches are cut in the direction perpendicular to the parallel light waveguides into planar lightwave circuits, a transparent electrode is deposited inside the trenches, and the trenches are filled with polymer-network liquid crystal. The typical attenuation range is 18 dB when the driving voltage is <20 Vrms at 1.55-μm wavelength. The power consumption is estimated to be very low (200 nW/ch)     

Evaluation of gamma-ray and neutron energy for area monitoring system in the IFMIF/EVEDA accelerator building

The engineering validation of the IFMIF/EVEDA prototype accelerator, up to 9 MeV by supplying the deuteron beam of 125 mA, will be performed at the BA site in Rokkasho. A design of this area monitoring system, comprising of Si semiconductors and ionization chambers for covering wide energy spectrum of gamma-rays and ³He counters for neutrons, is now in progress. To establish an applicability of this monitoring system, photon and neutron energies have to be suppressed to the detector ranges of 1.5 MeV and 15 MeV, respectively. For this purpose, the reduction of neutron and photon energies throughout shield of water in a beam dump and concrete layer is evaluated by PHITS code, using the experimental data of neutron source spectra. In this article, a similar model using the beam dump structure and the position with a degree of leaning for concrete wall in the accelerator vault is used, and their energy reduction including the air is evaluated. It is found that the neutron and photon flux are decreased by 10⁴-order by employing the local shields using concrete and polyethylene around beam dump, and the photon energy can be suppressed in the low energy.     

Water Treatment Using Discharge Generated in Cavitation Field with Micro Bubble Cloud

A new method of wastewater treatment using electric discharge in the water cavitation field formed by a large number of micro bubbles generated by high‐speed water flow is proposed in this paper. Indigo carmine solution, which is a type of dye, with a concentration of 9 mg/liter was used as the specimen solution for demonstration of water treatment. The total volume of solution and the average speed of solution in the cavitation field were 20 liters and about 7.4 m/s, respectively. An absorbance decrease rate of 96% was obtained in 50 min of treatment time at the electrode distance of 2 mm and discharge power of 16 W. It was also found that the efficiency of decolorization was improved by changing the electrode location. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 1–10, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22483     

Development of microbubble aerator for waste water treatment using aerobic activated sludge

In large-scale waste water treatment plants, the aerobic biochemical reactor is the most important process, where the oxygen supply into the microorganisms often limits the overall waste water treatment rate. On the other hand, several kinds of microbubble distributors have been developed to enrich the oxygen dissolution in water. Therefore, the application of microbubbles for a waste water treatment system was investigated in this study.The oxygen absorption performance of typical microbubble generators was compared with typical bubble generators. To evaluate each bubble generator, the liquid-phase volumetric oxygen transfer coefficient, gas hold-up and power consumption per unit liquid volume were measured in a bubble column attached to each bubble generator. All the microbubble generators allowed the oxygen to dissolve faster than the typical aerators. The spiral liquid flow type microbubble generator had the highest oxygen transfer coefficient even at a low air flow rate although it used more energy than the typical distributors.To improve an industrial waste water treatment system, a novel aeration system utilizing a spiral liquid flow type microbubble generator was proposed in this study. The present system has some advantages such as compact size, portability and fast oxygen dissolution rate. To ensure the performance for organic waste water treatment, the effects of the aeration rate, dissolved oxygen concentration and device properties on the specific consumption rate of model organic waste were investigated. For the novel aeration system, the most suitable conditions to treat organic waste were found.     

Low temperature CO pulse adsorption for the determination of Pt particle size in a Pt/cerium-based oxide catalyst

Unexpectedly large amounts of CO adsorption have resulted from a pulse adsorption experiment at 323 K, giving about 300% Pt dispersion in a Pt/cerium-based oxide catalyst. An in situ diffuse reflectance infrared Fourier transform spectroscopic investigation on a Pt/cerium-based oxide during CO adsorption has revealed that carbonate species on the cerium oxide surface are responsible for the unrealistically large CO adsorption at 323 K, as a result of CO spillover. Lowering the temperature to 195 K considerably diminished the amount of CO adsorption. The size of the Pt particles in the Pt/cerium-based oxide catalyst was determined by CO pulse adsorption at 195 K and showed good agreement with the particle size determined by X-ray diffraction and low energy ion scattering. This indicates that CO pulse adsorption at 195 K is a useful technique to reliably estimate the Pt particle size in a Pt/cerium-based oxide catalyst.     

Veno-occlusive disease of the liver after allogeneic bone marrow transplantation in children with hematologic malignancies: incidence, onset time and risk factors

One hundred and forty children with hematologic malignancies undergoing allogeneic BMT were reviewed in order to clarify the incidence, onset time, and risk factors for veno-occlusive disease (VOD) of the liver. Thirty-eight patients (27.1%) developed VOD diagnosed according to the Seattle clinical criteria. Seventeen patients developed VOD within 20 days of transplantation (early-onset) and in 21 patients developed after day 20 (late-onset) including eight patients with histological confirmation. Late-onset VOD occurred from day 21 to day 508 (median day 39). Moderate or severe VOD developed in 11 early-onset and 13 late-onset patients. Death occurred in eight early-onset and 10 late-onset patients. Serum albumin and cholinesterase levels prior to the start of pretransplant conditioning were significantly lower in early-onset VOD than in late-onset VOD. Multivariate analysis showed that low serum albumin levels (< or =3.7 g/dl) prior to the start of pretransplant conditioning was most strongly associated with the development of VOD. Donor mismatch (other than HLA-matched relatives), use of minocycline, and a long interval (> or =13 months) between diagnosis and BMT were also significantly associated with the development of VOD. In contrast, use of fosfomycin was associated with a decreased risk. Our data suggest that hepatic function reserve is important in the development and onset time of VOD. Veno-occlusive disease of the liver is a complication which may occur a long time after transplantation.     

Overexpression of c-myc induces apoptosis at the prophase of meiosis of rat primary spermatocytes

Serum samples from 36 cervical carcinoma patients, 33 patients with high-grade squamous intraepithelial lesions, and 31 cytologically normal women were tested by enzyme-linked immunosorbent assay (ELISA) using human papilloma virus type 6 (HPV 6) and HPV 16 virus-like particles as antigens. Forty serum specimens from 1-year-old children were used to assign cutoff points. When serum samples from the subjects infected with HPV 16 were tested in an HPV 16 ELISA detecting immunoglobulin A (IgA), IgG, and IgM binding, 61% showed IgA, 44% showed IgG, and 39% showed IgM reactivity. Of HPV 6- or 11- or HPV 18-infected subjects. fewer than 17% showed IgA or IgG responses and 33% showed IgM reactivity. In contrast, 13% showed IgA, 10% showed IgG, and 16% showed IgM reactivity in the HPV DNA-negative controls. The results suggest that the IgA and IgG responses are HPV 16 specific and the IgM response is cross-reactive to different HPV types. On the other hand, the serological responses to HPV 6 did not differ in the patient and control groups. The percentages of patients positive for both IgA and IgG antibodies were significantly higher in the groups with high-grade squamous intraepithelial lesions (12% [4 of 33]; P = 0.04) and cancer (17% [6 of 36]; P = 0.02) than in the healty women (0% [0 of 31]), and the percentages for either IgA or IgG were higher for the cancer group (47% [17 of 36]; P = 0.01) than in the normal group (19% [6 of 31]). Most sera positive for IgA and IgG in the patient groups showed higher titers than those in the normal group. All these results suggest that high IgA and IgG responses are good indicators for estimating HPV 16 infection.     

Inflammatory sensory ataxic neuropathy presenting with alternating skew deviation on lateral gaze: a case report

We report a 56-year-old female with chronic progressive sensory ataxic neuropathy presenting with alternating skew deviation on lateral gaze in the clinical course. She initially developed dysesthesias in the hands and feet asymmetrically, then gait disturbance developed over several months, and she was admitted to our hospital. Neurological examinations revealed profound deep sensory loss and mild superficial sensory disturbance with the absence of deep tendon reflexes, but muscular strength was completely preserved. EMG showed no evoked response of sensory nerve velocities and normal motor nerves. Sural nerve biopsy showed moderate demyelination with mild infiltration of inflammatory cells, and no vasculitis or onion bulb formation. CSF examination revealed elevation of cell counts and protein with marked intrathecal IgG synthesis and myelin basic protein, but finding of neurosyphillis. Serological examinations did not show any evidence of collagen disease, paraproteinemia, retrovirus infections or Lyme disease. Serum antiganglioside antibodies and anti-Hu antibody were negative. No evidence of malignancy was seen by radiological examinations and assays of tumor markers. In the weeks after admission, gait ataxia progressively worsened, and then she developed alternating skew deviation on lateral gaze, suggesting that the CNS was involved. No responsible lesion was detected on MRI. Corticosteroid administration improved not only the CSF findings, but also the neurologic symptoms, including the alternating skew deviation on lateral gaze. Although the disease entity was not identified, inflammatory demyelinating processes and immune-mediated mechanisms were considered to play important roles.     

Ion beam analyses of surface films formed on amorphous Fe12Mo18C alloy in 1 N HCl

The Rutherford backscattering with 2 MeV He⁺ and the ¹⁶O(d,p)¹⁷O¹ nuclear reaction with 1.8 MeV D₂⁺ were utilized to determine the concentration profiles of iron, molybdenum and oxygen in the surfaces of an amorphous Fe12Mo18C alloy polarized in 1 N HCl at potentials from ? 0.17 to 1.6 V(SCE). The thickness of the surface film was estimated as 20–200 nm. In the primary active region, selective dissolution of iron and carbon causes enrichment of molybdenum ions in the corrosion product film and of metallic molybdenum in the topmost part of the underlying alloy. A further potential increase led to a decrease in the molybdenum content in the film by transpassive dissolution. Molybdenum ions were not concentrated in the film formed in the stable passive region of 0.5–1.5 V(SCE). The high passivating ability of the amorphous alloy even in the aggressive HCl was ascribed to the homogeneity of the alloy structure as well as to the effect of molybdenum.