BIOGAS RECOVERY FROM A THERMALLY TREATED SEWAGE SLUDGE BY A FIXED-BED ANAEROBIC BIOREACTOR

Biogas recovery from the anaerobic digestion of sewage sludge which is discharged from municipal wastewater treatments generally requires a large scale digester owing to the slow biodegradability of the sludge compounds. To achieve an effective methanogenesis from the sludge as the raw materials, thermal pretreatmenls of the sludge were conducted to improve the sedimentation efficiency of the treated sludge and the filtrate obtained was anaerobically digested in fixed-bed bioreactors with baked clay, melted slug and rhyolitic lava.

Methane formation from the intact activated sludge (10g/l) was 11 methane/I after 25-day fermentation without heat treatment (control), whereas in the case of treating for 1 h at 121°C, 2.1 I methane/I was produced from the whole treated sludge (10g/l) and 2.91 methane/1 was produced at pH 4 at the same heat treatment. However, no more methane was produced when the sludge was treated with 0.1 N NaOH or H₂SO₄ at 121°C for 1 h although lower fatty acids were accumulated.

The filtrates from heat treated sludge either at 121°C for 1 h at pH 4 or at 121°C for 1 h contained 2200 and 4400 mg COD/I, respectively. The filtrates obtained were anaerobically digested in fixed bed reactors. For the former, at COD loading 32.4g/l/day, the methane production rate was 2.91/l/day with 52.6% of COD reduction at 1.5 h of hydraulic retention time, whereas, for the latter, methane production rate was 2.11/1/day with 26.2% of COD reduction at 2.4 h retention time (COD loading 47.8).

It would be concluded that the heat treatments of discharged sludge from aeration tank might be a promising means for the treatment of activated sludge since the heat treatment could decrease the specific resistance of filtration of sludge and the filtrate discharged could be easily converted to methane as a fuel energy.     

A wind tunnel study on control methods for cable dry-galloping

The common vibration of cable caused by rain-wind combination has been known as most typical type and a lot kind of its countermeasures has been proposed for suppressing this phenomenon. Recently, stayed-cables were also proved that they could be excited in dry state (without rain), which is called dry-galloping. Recently, its mechanisms have been explained by axial flow, Reynolds number and so on. To clarify the characteristics of this galloping, wind tunnel test of a cable model with various kinds of wind angle was conducted. Then, three types of countermeasure were examined to suppress dry- galloping of bridge cable. The tests confirmed that the occurrence of dry-galloping depends on relative wind attacked angles and onset reduced wind speed. Furthermore, single spiral wire, double spiral wire and circular ring were found to have high effectiveness in mitigating this galloping when those are installed properly.     

Plasma Sphingosine-1-Phosphate Levels Are Associated with Progression of Estrogen Receptor-Positive Breast Cancer

Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.     

Delineating the Molecular Events Underlying Development of Prostate Cancer Variants with Neuroendocrine/Small Cell Carcinoma Characteristics

The treatment landscape of prostate cancer has changed dramatically following the advent of novel systemic therapies, most of which target the androgen receptor (AR). Agents such as abiraterone, enzalutamide, apalutamide, darolutamide were designed to further suppress androgen receptor signaling following gonadal suppression achieved by first-line androgen deprivation therapies. These potent AR targeting agents are increasingly used in the earlier stages of the disease spectrum with the goal of delaying disease progression and extending survival. Although these therapies are effective in controlling prostate tumors dependent on or addicted to AR signaling, prostate tumors surviving the onslaught of potent treatments may evolve and develop drug resistance. A substantial proportion of treatment failures can be explained by the development of treatment-induced aggressive prostate cancer variants such as neuroendocrine/small cell carcinoma. These emerging disease entities demand detailed characterization and precise definitions. We postulate that these treatment-induced prostate cancer entities should be defined molecularly to overcome the drawbacks associated with the current clinical and pathological definitions. A precise molecular definition conforms with current knowledge on the molecular evolution of this disease entity and will enable early detection and early intervention.     

FLUORESCENCE ENHANCEMENT OF 6H-BENZO[cd]PYREN-6-ONE (NAPHTHANTHRONE): EFFECTS OF CONCENTRATION,LIGHT INTENSITY,AND DEUTERATION OF SOLVENTS

Fluorescence of naphthanthrone, 6H-benzo[cd]pyren-6-one, in degassed organic solution increases by a factor of 10–100 on strong irradiation and the spectrum is blue-shifted. To clarify the mechanism of the fluorescence enhancement, we investigated effects of intensity of irradiation, deuteration of solvents, and concentration of naphthanthrone on the enhancement. The fluorescence was more rapidly enhanced with stronger irradiation, though there was a latent period of several minutes. The enhancement was, however, reduced to 30–70% by deuteration of the solvents. The spectra of enhanced fluorescence showed more defined vibrational structure and larger blue-shift as the concentration was decreased from 10^?4 to 10^?6 M. These experimental results were interpreted on the basis of the associative complex model: the association of naphthanthrone with a solvent molecule proceeds step-wisely in a solvent cage by several times of excitation and undergoes kinetic isotope effects. At lower concentrations, the movement of the associative complex is more strongly suppressed, leading to enhanced fluorescence spectra with clearer vibrational structure and larger blue-shift.     

Enhanced accumulation of caffeic acid,rosmarinic acid and luteolin-glucoside in red perilla cultivated under red diode laser and blue LED illumination followed by UV-A irradiation

Red perilla (Perilla frutescens var. purpurea cv. Akajiso) is a plant rich in polyphenols such as rosmarinic acid and luteolin with great potential as a functional food material. The present study examines whether growth under controlled artificial illumination could be used for cultivation of red perilla to enhance rosmarinic acid and luteolin content. Red perilla plants were cultivated for 7 weeks in a greenhouse or in a closed environment under a regime of artificial light comprising 80% red laser diode (680 nm) and 20% blue LED (460 nm) at 360 μmol/m²/s for 14-h light period, followed by a 2-h illumination with ultraviolet A (365 nm). HPLC analysis of polyphenols revealed that the content of caffeic acid and rosmarinic acid was 7.9 and 6.6 times higher respectively, in plants grown under artificial light than in greenhouse grown plants. The content of luteolin-7-O-glucoside was 20 times higher in the light treated plants compared to the greenhouse grown ones. Our results indicate that artificial illumination is effective for inducing the accumulation of rosmarinic acid and luteolin with functional food properties in red perilla.     

Comparative studies on magnetic flux relaxations of varied spherical toroids produced by co‐helicity merging

The co‐helicity merging operations of compact toroid (CT) and spherical tokamak (ST) have been performed with external toroidal fields in the CT/ST merging device TS‐4. The low‐q (safety factor) CT merging as the compact RFP merging and the spheromak merging show the flux conversion from toroidal to poloidal in the course of the reconstruction of the Taylor force free state. The relaxation to the Taylor state proceeds through the following three states: (1) axisymmetric merging with increasing toroidal flux; (2) increase in the poloidal flux Ψ; and (3) relaxation to the Taylor state. The high‐q ST merging shows different relaxation process from those of the compact RFP and the spheromak mergings. Increases in Ψ were not clearly observed in the ST merging. The measured eigenvalues λ show that ST's, especially high‐q ST's, approach a unique intrinsic equilibrium state that has a λ proportional to Ψ with a longer lifetime than that of CT's. When external toroidal field is set in a certain range between the low‐q operation and the high‐q operation for ST's, an abnormal phenomenon was found in the ST formation, namely, a drastic decrease in the plasma lifetime. This phenomenon is characterized by very weak poloidal flux generations during the initial plasma production phase and the subsequent plasma separation phase when the plasma starts detaching from the flux core. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(4): 7–15, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20069     

Melting and crystallization behavior of metallic alloy in the composites with polyacrylate

Composites of poly(n‐buthyl acrylate) (PnBA) and eutectic metallic alloy composed of Bi, In, and Sn were prepared by mechanically mixing them above the melting point of the metallic alloy, and glass transition temperature of PnBA. The heating curves of differential scanning calorimetry (DSC) of the composite of PnBA and the metallic alloy showed an endothermic peak below the melting point of the metallic alloy without polymers, which indicated the formation of the interfacial phases of the metallic alloy with a lower melting point. The exothermic peaks of the cooling curves were broadened and shifted to the temperature lower than the melting point of the metallic alloy without polymers, which suggests that the crystallization of the metallic alloy was suppressed by the interaction. The mechanism of lowering the melting points and suppression of the crystallization was discussed based on the results of DSC, transmitting electron microscopy, and X‐ray diffractometry. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Analysis of non-linear transmission lines by frequency domain perturbation method

We discuss a numerical method for solving non-linear transmission lines in the frequency domain. Such transmission lines are widely used for communications such as in GaAs integrated circuits and varactor diode circuits. The circuit equations are described by non-linear partial differential equations, so their analysis is very complicated compared with that of linear transmission lines. In this paper we propose a frequency-domain perturbation method for weakly non-linear transmission lines where the wave-forms are approximated by Fourier expansions and each frequency component is calculated by a modified perturbation method. To improve convergence, we introduce two new techniques, the compensation method and the homotopy method, which help to make the iteration stable and can be applied to a wide class of non-linear transmission lines. We have analysed shock wave phenomena in example. © 1997 by John Wiley & Sons, Ltd.