Performance Evaluation of a Full-Scale Deep U-Tube Utilizing Ozonated Oxygen as the Process Gas for Treating Drinking Water

A deep U-tube for treating drinking water is composed of a coaxial inner tube serving as an efficient concurrent down-flow ozone dissolver and an outer column carrying out reactions between ozone and organic substances dissolved in the water after sedimentation treatment. In the present study, we developed a novel simulation model of the U-tube reactor, assuming that the U-tube is composed of a plug flow section (inner tube) followed by a tanks-in-series section (outer bubble column) and taking into account the reactions involved, and the effects of the hydrostatic pressurization on the flow and absorption equilibrium for the ozone and inactive gases in developing the mass balance models. We constructed an algorithm to evaluate the U-tube reactor performance based on the mass balance models. The hydrodynamics and mass transfer characteristics in the inner tube were measured and their correlations were incorporated in the simulation model. Available literature data and correlations on the rates of reactions between ozone and organic substances, the gas-liquid equilibrium for the active and inactive gases and the fluid mixing properties are also incorporated in the simulation model. The simulation results well explained the available data on the ozone absorption efficiency and the removal efficiency of odorous material (2-MIB) in a pilot plant and a real U-tube reactor. It is found that the ozone absorption is practically a single function of the gas/liquid ratio, while the decomposition efficiency of 2-MIB is a single function of the ozone dose for the water quantity to be treated

Influence of water vapor on performance degradation and microstructural change of (La,Sr)(Co,Fe)O3-δ cathode

In this study, single cells employing a La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) cathode were operated with a supply of humidified oxygen to the cathode at 1000°C for 100 h to investigate the influence of water vapor on the performance and microstructure of LSCF cathode. When a gaseous mixture of 20% H2O−80% O2 was supplied to the cathode, the performance of LSCF cathode continuously lowered during a discharge at 300 mA cm−2 for 100 h. Then, the microstructures of surface and cross-section of LSCF cathode were observed by scanning electron microscopy. The surface morphology was drastically changed by the discharge operation. A SrO layer was formed at the outermost surface of cathode, indicating that the strontium segregation was accelerated by water vapor. In response to this phenomenon, the formation amount of cobalt- and/or iron-based oxides enlarged inside the electrode. These microstructural and phase changes would be responsible for the performance deterioration of LSCF cathode

Tumor-infiltrating Regulatory T cells – Phenotype and Expansion by Radiation Therapy

Regulatory T cells (Treg) are the master immune-suppressor cells, with a double-edged sword. Treg protect us from autoimmunity, damages from excessive inflammation, and help us maintaining homeostasis in mucosal surface. On the other hand, Treg can be negative force against anti-tumor immunity in the tumor microenvironment (TME), which need to be targeted to maximize the effects of cancer immunotherapies. However, the exact phenotype and molecular basis of suppressive function of Treg in the TME have not been fully elucidated. Especially of translational relevance; what is the phenotype of tumor-infiltrating Treg (TIL-Treg) under the fundamental cancer therapy such as radiotherapy, and what is the determinant molecules for human TIL-Treg have not been fully elucidated. To answer those questions, in my thesis projects, I have elucidated the TIL-Treg phenotype post radiotherapy (RT), and discovered novel human TIL-Treg targeting molecules. In RT-Treg project, we have shown that RT significantly increased the phenotypically activated and, importantly functionally suppressive Treg in the TME. To the best of our knowledge, we were the first to demonstrate that irradiated TIL-Treg are indeed functionally suppressive, using the in vitro micro-suppression assay, using TIL post-RT. Our results also suggest that post-RT Treg expansion is likely independent of TGF-beta nor IL-33, but at least partly due to the proliferation of the Treg in the tumor. In human TIL-Treg project, we performed RNAseq from prostate cancer, glioblastoma and renal cell carcinoma (and urothelial carcinoma as well) patients and identified novel targets highly expressed in TIL-Treg, including DUSP1, DUSP4, RGS1 (and RGS16). Despite its high expression in Treg, DUSP1 showed unique downregulation upon activation, which presents a stark contrast with most Treg-associated molecules many of which increase their expression in activation. DUSP1 accordingly showed reciprocal expression pattern with DUSP4. From the data and close homology with DUSP1 and DUSP4, I hypothesized that DUSP1 and DUSP4 reciprocally regulate Treg activation and function. In depth in vitro and in vivo studies are underway to further elucidate the functional roles of these molecules in TIL-Treg (and TIL)

B型肝炎ウイルスGenotype CにおけるX領域Codon38変異は発癌のリスクファクターである

BACKGROUND/AIMS: The hepatitis B virus (HBV) genotype C is associated with the development of hepatocellular carcinoma (HCC). In addition, the HBV X gene, which encodes the pleiotropic transactivator HBx, has also been associated with the development of HCC. In this study, we investigated whether nucleotide changes in the X gene of genotype C are associated with the development of HCC. METHODS/RESULTS: We sequenced the X gene in age- and sex-matched 39 HBV-infected patients with HCC and 36 HBV-infected patients without HCC. A novel nucleotide change that resulted in a proline to serine substitution at codon 38 in HBx (codon-38 change) was preferentially found in patients with HCC. Then, sera were collected from a new group of age- and sex-matched 52 patients with HCC and 51 patients without HCC. In this cohort also, the codon-38 change was associated with HCC. Multiple logistic regression analysis showed the prevalence of the codon-38 change was significantly associated with HCC in all patients (P=0.001, odds ratio: 4.89). CONCLUSION: The codon-38 change in genotype C is an independent risk factor for the development of HCC and may serve as a useful molecular marker for predicting the clinical outcomes in patients infected with HBV

Factors governing the fluorination of hydroxyapatite by an ionic liquid

Fluorapatite exhibits improved bone-bonding and chemical durability under neutral and acidic conditions compared with hydroxyapatite. Typically, an aqueous fluoride solution is used for F− incorporation into the hydroxyapatite. Use of an ionic liquid as F− source provides highly-concentrated ionic environment and can lead to more effective fluorination. In this study, two ionic liquids were added during the synthesis of hydroxyapatite under various conditions, and the differences in the crystalline structure and chemical durability of the resulting fluorapatites were investigated. 1-ethyl-3-methylimidazolium tetrafluoroborate was quite effective for F− incorporation, but not 1-ethyl-3-methylimidazolium hexafluorophosphate. When the temperature was increased to 80 °C, not only the hydroxyapatite or fluorapatite but also CaF2 was generated as a by-product. When the initial pH was decreased to 7, the formed product fully converted to CaF2. The solubility of the product tended to be suppressed in acidic conditions with increase in amount of fluorine substituted in the crystal lattice

Magnolol Protects against MPTP/MPP+-Induced Toxicity via Inhibition of Oxidative Stress in In Vivo and In Vitro Models of Parkinson's Disease

The aim of this study is to investigate the role of magnolol in preventing 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP-) induced neurodegeneration in mice and 1-methyl-4-phenylpyridinium ion-(MPP+-) induced cytotoxicity to human neuroblastoma SH-SY5Y cells and to examine the possible mechanisms. Magnolol (30 mg/kg) was orally administered to C57BL/6N mice once a day for 4 or 5 days either before or after MPTP treatment. Western blot analysis revealed that MPTP injections substantially decreased protein levels of dopamine transporter (DAT) and tyrosine hydroxylase (TH) and increased glial fibrillary acidic protein (GFAP) levels in the striatum. Both treatments with magnolol significantly attenuated MPTP-induced decrease in DAT and TH protein levels in the striatum. However, these treatments did not affect MPTP-induced increase in GFAP levels. Moreover, oral administration of magnolol almost completely prevented MPTP-induced lipid peroxidation in the striatum. In human neuroblastoma SH-SY5Y cells, magnolol significantly attenuated MPP+-induced cytotoxicity and the production of reactive oxygen species. These results suggest that magnolol has protective effects via an antioxidative mechanism in both in vivo and in vitro models of Parkinson's disease