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Reaction kinetics of supercritical water oxidation (SCWO) of ammonia/methanol mixture was investigated at 530 °C, 25 MPa, and [NH 3 ] 0 = 2.9–3.0 mmol/L, both experimentally and computationally. Ammonia conversion increased with an increase in the initial methanol concentration. Ammonia oxidation was retarded after complete oxidation of methanol. The major product from ammonia oxidation was N 2 O. Methanol decomposition and CO oxidation were accelerated in the ammonia/methanol mixture under the conditions used. Calculations using an elementary reaction model show that ammonia and methanol mutually promote their oxidation through radical intermediates. The mixture effect in the SCWO of ammonia/methanol can be explained by a radical chain mechanism in which ammonia and methanol share the radicals generated and promote mutual oxidation reactions. The ammonia oxidation cycle initiated by methanol co-oxidation was maintained by nitrogen-containing species even after methanol had been completely oxidized.

Many accidents have occurred in universities and the accident reports are accumulated in most universities. The information described in the accident reports must be used effectively to prevent a recurrence of the accidents. In this study, we applied text analytics to the description written in 373 accident reports in a university as a case study. Information mining method was adopted for the contents analysis, and 9 factors based on m-SHEL and human error, that is “software”, “hardware”, “environment”, “liveware2”, “management” “slip”, “lapse”, “mistake”, and “violation” were used for morphological analysis for description in report. The factors in each category of accident situation were extracted, and it is suggested that text analytics is one of the most effective methods to analyse the accident reports in universities.

Current research analyzing the effects of water in the field of homogeneous and heterogeneous reactions of organics in sub- and supercritical water are reviewed in this article. Since the physical properties of water (e.g., density, ion product and dielectric constants) can affect the reaction rates and mechanisms of various reactions, understanding the effects that water can have is important in controlling reactions. For homogeneous reactions, the effects of water on oxidation, hydrolysis, aldol condensation, Beckman rearrangement and biomass refining were introduced including recent experimental results up to 100 MPa using special pressure-resistance equipment. For heterogeneous reactions, the effects of ion product on acid/base-catalyzed reactions, such as hydrothermal conversion of biomass-related compounds, organic synthesis in the context of bio-refinery, and hydration of olefins were described and how the reaction paths are controlled by the concentration of water and hydrogen ions was summarized.

An acid-catalyzed dehydration mechanism was investigated for formic acid decomposition through calculations based on density functional theory. In previous experimental investigations, formic acid dehydration in hot compressed water was reported to proceed faster at pressures >30 MPa. Higher concentration of hydrogen ions because of the large ion product of water at high pressure was believed to contribute to the acceleration of the dehydration reaction. In this study, the structures and energies of the transition states and intermediates were determined through calculations based on density functional theory with the B3LYP/6-311+G(2d,p) level of theory. A comparison of their threshold energies indicated that the dehydration proceeded via the protonation of hydroxyl oxygen, and that the acid-catalyzed dehydration was energetically more favored than the water-catalyzed mechanism. These results suggested that the abundant hydrogen ions in hot compressed water at high pressure accelerated the dehydration occurring via an acid-catalyzed formic acid dehydration mechanism.

The effects of pressure on formic acid decomposition in sub- and super-critical water from near the critical pressure to extremely high pressures (20–100 MPa) at temperatures of 380 and 400 °C were investigated. Near the critical pressure, the dehydration and decarboxylation rates decreased with increasing pressure. The apparent activation volumes near the critical pressure were high where the isothermal compressibility of water was large, implying that formic acid attracts water molecules better than the transition state does, and that the partial molar volume of the transition state is larger than those of the reactants. At higher pressures, dehydration rate increased with increasing pressure. Comparisons with experimental results for HCl addition at constant pressure suggest that dehydration proceeds via an ionic reaction at high pressures. The pressure may affect formic acid decomposition in supercritical water negatively through solvation effects near the critical pressure, and positively through ionic reactions above 30 MPa.

Reaction kinetics of methanol oxidation in supercritical water at high pressure condition (420 °C; 34–100 MPa; ρ = 300–660 kg/m 3 ) was investigated. Pseudo-first order rate constant for methanol decomposition increased with increasing water density. Effects of supercritical water on the reaction kinetics were investigated using a detailed chemical kinetics model. Incorporating the effect of diffusion in a reduced model revealed that overall kinetics for SCWO of methanol is not diffusion-limited. Roles of water as a reactant were also investigated. The dependence of sensitivity coefficient for methanol concentration and rate of production of OH radical on water density indicated that a reaction, HO 2 + H 2 O = OH + H 2 O 2 , enhanced the OH radical production and thereby facilitated the decomposition of methanol. It is presumed that concentration of key radicals could be controlled by varying pressure intensively.

Epigenetic alteration is an emerging paradigm underlying the long-term effects of chemicals on gene functions. Various chemicals, including organophosphate insecticides and heavy metals, have been detected in the human fetal environment. Epigenetics by DNA methylation and histone modifications, through dynamic chromatin remodeling, is a mechanism for genome stability and gene functions. To investigate whether such environmental chemicals may cause epigenetic alterations, we studied the effects of selected chemicals on morphological changes in heterochromatin and DNA methylation status in mouse ES cells (ESCs). Twenty-five chemicals, including organophosphate insecticides, heavy metals and their metabolites, were assessed for their effect on the epigenetic status of mouse ESCs by monitoring heterochromatin stained with 4¢,6-diamino-2-phenylindole (DAPI). The cells were surveyed after 48 or 96 h of exposure to the chemicals at the serum concentrations of cord blood. The candidates for epigenetic mutagens were examined for the effect on DNA methylation at genic regions. Of the 25 chemicals, five chemicals (diethyl phosphate (DEP), mercury (Hg), cotinine, selenium (Se) and octachlorodipropyl ether (S-421)) caused alterations in nuclear staining, suggesting that they affected heterochromatin conditions. Hg and Se caused aberrant DNA methylation at gene loci. Furthermore, DEP at 0.1 ppb caused irreversible heterochromatin changes in ESCs, and DEP-, Hg- and S-421-exposed cells also exhibited impaired formation of the embryoid body (EB), which is an in vitro model for early embryos. We established a system for assessment of epigenetic mutagens. We identified environmental chemicals that could have effects on the human fetus epigenetic status.

We have developed a gas chromatography-mass spectrometry (GC–MS) method to determine five phthalate monoesters (monoethyl phthalate (MEP), mono-n-butyl phthalate (MBP), mono-(2-ethylhexyl) phthalate (MEHP), monoisononyl phthalate (MINP) and monobenzyl phthalate (MBz)) in human urine. Human urine samples were subjected to enzymatic deconjugation of the glucuronides followed by extraction with hexane. The extracted phthalate monoesters were methylated with diazomethane, purified on a Florisil column and then subjected to GC–MS analysis. The recoveries from urine spiked with five phthalate monoesters were 86.3%–119% with coefficients of variation of 0.6%–6.1%. We measured phthalate monoester levels in human urine by analyzing 36 samples from volunteers. MBP and MEP were detected in all samples, and their median concentrations were 60.0 and 10.7 ng/mL, respectively. MBzP and MEHP were found in 75% and 56% of samples, and their median concentrations were 10.9 and 5.75 ng/mL, respectively. MINPs were not detected in most samples (6% detectable). Women had significantly (p < 0.05) higher mean concentrations of MBP and MEP than men. The estimated daily exposure levels for the four parent phthalates excluding diisononyl phthalate ranged from 0.27 to 5.69 μg/kg/day (median).

Reaction kinetics of methanol and ethanol oxidation in supercritical water at 520–530 °C and 24.7 MPa were investigated both experimentally and by computational simulation. Furthermore, studies were performed on the oxidation of the two alcohols in binary mixtures. For the methanol system, experimental data showed that the methanol conversion decreased with increasing initial methanol concentration in the low concentration range (from 6.48 × 10−6 to 3.94 × 10−5 mol/l), whereas the conversion increased for initial concentrations in the high concentration range (from 2.23 × 10−4 to 1.55 × 10−3 mol/l). Kinetic analyses based on the elementary reaction model showed that production of OH from the reaction of H2O with HO2 seemed to play an important role at the low methanol concentrations and that the characteristic dependence of methanol conversion on initial methanol concentration was due to the very high concentration of H2O in supercritical water oxidation of methanol. For the binary system, it was found that methanol conversion was accelerated by ethanol addition whereas ethanol oxidation was slightly retarded by the presence of methanol. Calculation with an elementary reaction model could reproduce the phenomenological mutual effects of alcohols with respect to reaction rates, and it was found that the acceleration/retardation effect of conversions could be well characterized by the time profile of OH radical, rather than HO2 radical.

The contribution of ionic reactions to phenol oxidation has been investigated in subcritical and supercritical water. From the experiments conducted at 24.7 MPa, it was found that the phenol conversions at 360°C were slightly higher than that at 400°C. We calculated the concentration of phenolate anion at 24.7 MPa using semiempirical model reported by Sue et al. (2002). The calculated concentration of phenolate anion at 360°C is about seventh order of magnitude higher than that at 400°C because of the high ion product of water at 360°C. The electron transfer (ET) reaction (C6H5O– + O2 = C6H5O· + O2–) was investigated as one of the reasons for the enhancement of phenol oxidation in subcritical water. We estimated the equilibrium constant of the ET reaction using density functional theory calculations, which suggests that the ET reaction should be taken into consideration in the region of high ion product of water. We also discussed the dimerization reaction as consumption reactions of phenoxy radical and other reactions involving inorganic ion species such as O2–, OH– and HO2–. When phenoxy radical and O2– are produced effectively, these reactions could be more favorable in subcritical water than in supercritical water. From these discussions, phenol oxidation in subcritical water could be enhanced by the ionic reaction mechanism because of a high ion product of water.

Simultaneous measurements of on-road and in-vehicle NO and NO2 levels, particle number concentrations (PNCs), and particles size distributions were performed while driving using a test vehicle equipped with real-time sensors. The results obtained on regional roads showed that heavy-duty vehicles in traffic seem to have a major impact on on-road air quality. Measurements on highways that included a 10km tunnel and a 2km uphill section of road indicated that sub-50nm particles have different features from the other species because of their higher volatility. The other species showed quite high on-road concentrations in the tunnel. In-vehicle conditions were made similar to the on-road ones by setting the air conditioning (AC) mode to the fresh air mode. The in-vehicle NO2 concentration in the tunnel was over 0.50ppmV, which is almost five times higher than the 1-hour ambient air quality standard proposed by the World Health Organization (WHO). In sections other than the tunnel, the in-vehicle NO2 concentration was almost the same as the 1-hour WHO standard. Higher on-road NO2/NOx ratios than those of exhaust gases and different behavior of sub-50nm particles from other species suggested that NO2 and sub-50nm particles were mainly due to secondary products formed by atmospheric reactions.

We performed a neuroblastoma cell (Neuro2a) culture assay modified slightly from a method reported previously to provide a simple and sensitive evaluation of paralytic shellfish poisoning (PSP) toxicity in shellfish. The cell bioassay was just as sensitive for C-toxins as for gonyautoxins. The sensitivity of our cell bioassay was 4 times that of the current standard mouse bioassay. Using the cell bioassay, we evaluated PSP toxicity in 361 shellfish samples collected from Mikawa Bay and Ise Bay, Aichi Prefecture, Japan, from April 1999-March 2002. The results were compared with those obtained in a postcolumn derivatization liquid chromatographic analysis. PSP toxins were detected in 236/361 samples by both assays, and there was a fairly good correlation (r = 0.9001, n = 236, p0.001) between the results from the two assays. We applied this cell bioassay when short-necked clams in the bay turned poisonous in 2001. The chronological changes in PSP toxicity in the short-necked clams were analyzed and compared with those of the cell density of poisonous plankton (Alexandrium tamarense) occurring in the bay. The PSP toxicity in shellfish peaked 2 weeks after the cell density reached a maximum. We recommend using the cell bioassay for routine monitoring of PSP toxicity in shellfish living in natural marine environments.

BACKGROUND: The relative risk of mortality in low and high body mass index (BMI) categories in various ethnic groups remains a controversial subject.METHODS: To examine the relationship between BMI and mortality, a population-based prospective cohort study was conducted in two areas of Gunma Prefecture, Japan, in 1993. A total of 5,554 men and 5,827 women aged 40-69 years completed a self-administered questionnaire and were followed up until the year 2000. The hazard ratios (HRs) were estimated by the Cox proportional hazards model for different BMI classes.RESULTS: During the seven year follow-up period, 329 men and 147 women died. As compared with those in the reference BMI category (22.0-24.9 kg/m2), men and women in the lowest BMI category (

BACKGROUND: Few studies have examined the association of perceived health with socio-economic status, especially income, and social isolation and support in Japan. The purpose of this study is to clarify the associations among perceived health, lifestyle, and socio-economic status, as well as social isolation and support factors, in middle-aged and elderly Japanese. METHODS: Subjects were 9,650 participants aged 47-77 years who completed a self-administered questionnaire in 2000 in the second survey of a population-based cohort (the Komo-Ise study). The questionnaire included items on sociodemographic and socio-economic factors, social isolation and support, lifestyle, past history of chronic disease and perceived health. Perceived health was dichotomized into excellent or good health and fair or poor health. A logistic regression analysis was used to determine the odds ratios of socio-economic status, social characteristics and lifestyle in relation to self-reported fair or poor health. RESULTS: We found that household income, physical activity, sleeping, smoking habit, and BMI had a strong association with self-reported fair or poor health in middle-aged and elderly Japanese men and women. Male subjects tended to report fair or poor health as household income decreased. The results for women differed in that social isolation and low social support had a stronger association for self-reported fair or poor health than low household income. CONCLUSIONS: The results indicated that perceived health was associated with socio-economic and social characteristics among middle-aged and elderly residents in Japan.

The regulation of transcription and genome stability by epigenetic systems are crucial for the proper development of mammalian embryos. Chemicals that disturb epigenetic systems are termed epimutagens. We previously performed chemical screening that focused on heterochromatin formation and DNA methylation status in mouse embryonic stem cells and identified five epimutagens: diethyl phosphate (DEP), mercury (Hg), cotinine, selenium (Se), and octachlorodipropyl ether (S-421). Here, we used human induced pluripotent stem cells (hiPSCs) to confirm the effects of 20 chemicals, including the five epimutagens, detected at low concentrations in maternal peripheral and cord blood samples. Of note, these individual chemicals did not exhibit epimutagenic activity in hiPSCs. However, because the fetal environment contains various chemicals, we evaluated the effects of combined exposure to chemicals (DEP, Hg, cotinine, Se, and S-421) on hiPSCs. The combined exposure caused a decrease in the number of heterochromatin signals and aberrant DNA methylation status at multiple gene loci in hiPSCs. The combined exposure also affected embryoid body formation and neural differentiation from hiPSCs. Therefore, DEP, Hg, cotinine, Se, and S-421 were defined as an “epimutagen combination” that is effective at low concentrations as detected in maternal peripheral and cord blood.

A method for the simultaneous determination of multiple pesticide residues in agricultural products was developed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The sample was extracted with acetonitrile. Co-extractives were removed by GPC/graphitized carbon column SPE, and silica gel/PSA cartridge column SPE. Pesticides in the test solution were determined by LC-MS/MS using scheduled MRM. Recoveries of 124 pesticides from spinach, brown rice, soybean, orange and tomato were tested at the level of 0.1 µg/g, and those of 121 pesticides ranged from 70 to 120% (RSD≤15%). Pesticide residues in 239 agricultural products were investigated by this method, and residues of 49 pesticides were detected in 98 agricultural products.

Here we report a case of successful treatment with combination chemotherapy of carboplatin(CBDCA)and paclitaxel for a patient undergoing hemodialysis(HD)with cancer of unknown primary, conducted by monitoring the observed AUC of ultrafilterable CBDCA. CBDCA was administered at a dose of 125 mg on day 1 in each course, an amount which had been calculated by the Calvert formula(GFR: 0, target AUC: 5). HD was started at a point in time one hour after the completion of each CBDCA administration, and performed for 5 hours in each course. Blood samples were collected during the first 3 courses of chemotherapy to measure the plasma concentration of free-platinum. The observed AUCs(o-AUC)of CBDCA in the first, second and third courses were 3. 03, 3. 44 and 3. 50mg·min/mL, respectively. The o-AUC in the first course was lower than that in the second course. The o-AUC in the second course was nearly equal to that in the third course, while each o-AUC was below the target AUC(t-AUC). Partial response was achieved after two courses of the CBDCA and paclitaxel combination chemotherapy, with adverse events of Grade 3 neutropenia and Grade 3 peripheral neuropathy observed in each course after the second course of chemotherapy. o-AUC of CBDCA administered to HD patients can not only be below t-AUC, as in this case, but also oppositely above t-AUC in cases with different doses of CBDCA or HD settings. Our results suggest that the monitoring of o-AUC of CBDCA is useful when practicing CBDCA-based chemotherapy safely and effectively in cancer patients undergoing HD.

Placental transfer and body distribution of triphenyl tin chloride (TPTC) and tin chloride (SnCl2) were investigated in pregnant rats. Pregnant wistar rats were orally administered TPTC at 0, 1.0 and 2.0 mg/rat/day during 6-10 and 14-18 days of gestation, and with SnCl2 at 0 and 20 mg/rat/day on 7, 10 and 15 days of gestation (group treated 3 times) or 6-10 and 13-16 days of gestation at 0 and 20 mg/rat/day (group treated 9 times). On day 20 of gestation in rats treated with TPTC, and day 17 in rats with SnCl2, fetuses, placentas, maternal blood and organs were obtained for analyses. Mean fetal tin levels from rats treated with 1.0 and 2.0 mg TPTC were 0.05 and 0.11 microgram/g wet weight, respectively, these values being significantly (P < 0.01) higher than in the control group. The latter was higher than the former at a significance level of 5%. No significant difference between fetal tin levels from rats treated with SnCl2 and the control group could be detected. Following oral TPTC administration, tin was present in maternal liver, kidney and brain in high concentrations. Following the oral administration of SnCl2, the tin level was highest in bone and kidney, but none could be detected in the brain.

Explosive increases in skin cancers have been reported in more than 36 million patients with arsenicosis caused by drinking arsenic-polluted well water. This study and previous studies showed high levels of barium as well as arsenic in the well water. However, there have been no reports showing a correlation between barium and cancer. In this study, we examined whether barium (BaCl(2)) may independently have cancer-related effects on human precancerous keratinocytes (HaCaT). Barium (5-50 µM) biologically promoted anchorage-independent growth and invasion of HaCaT cells in vitro. Barium (5 µM) biochemically enhanced activities of c-SRC, FAK, ERK and MT1-MMP molecules, which regulate anchorage-independent growth and/or invasion. A SRC kinase specific inhibitor, protein phosphatase 2 (PP2), blocked barium-mediated promotion of anchorage-independent growth and invasion with decreased c-SRC kinase activity. Barium (2.5-5 µM) also promoted anchorage-independent growth and invasion of fibroblasts (NIH3T3) and immortalized nontumorigenic melanocytes (melan-a), but not transformed cutaneous squamous cell carcinoma (HSC5 and A431) and malignant melanoma (Mel-ret) cells, with activation of c-SRC kinase. Taken together, our biological and biochemical findings newly suggest that the levels of barium shown in drinking well water independently has the cancer-promoting effects on precancerous keratinocytes, fibroblast and melanocytes in vitro.

The concentrations of urinary tin in healthy adults in Aichi prefecture were determined by anodic stripping voltammetry over a period of three years (1986-1988), to obtain the normal tin level in urine and to elucidate the influence of environmental alterations on health conditions in the future.In addition to the above-mentioned method, the relationship to life style, dietary habits, smoking habits and living environment were studied, and the following results were obtained.1) The mean±standard deviation of urinary tin levels for males was 3.7±2.2 (μg/g creatinine), and 5.9±3.0 (μg/g creatinine) for females. The data showed logarithmic normal distributions in both sexes, and the maen concentration for females was significantly higher than that for males (P

For the on-site treatment of laboratory waste, we have been developing a compact-sized reaction system for the treatment of laboratory wastewater using supercritical water oxidation (SCWO) technology. Pharmaceutical laboratory wastewater is one of the most difficult wastewaters to treat because of its high concentration of halogenated organic compounds. We proposed a new cascade process in which two reactors are consecutively combined, carrying out hydrolysis in the first reactor followed by SCWO in the second reactor, for the complete removal of halogenated organic compounds. Dichloromethane was chosen as a representative model of chlorinated compounds. There have been many previous studies on the hydrolysis of dichloromethane, which results in the coproduction of formaldehyde and HCl. However, there has been less investigation on the kinetics of formaldehyde oxidation in supercritical water. In this study, we focus on the oxidation of formaldehyde in supercritical water with and without a catalyst. As a result, formaldehyde can be completely decomposed at 400 degrees C and 25 MPa within a very short contact time in a heterogeneous system with a MnO(2) catalyst.

Supercritical water oxidation (SCWO) is a reaction in which organics in an aqueous solution can be oxidized by O2 to CO2 and H2O at a very high reaction rate. In 2003, The University of Tokyo constructed a facility for the SCWO process, the capacity of which is approximately 20 kl/year, for the purpose of treating organic laboratory waste. Through the operation of this facility, we have demonstrated that most of the organics in laboratory waste including halogenated organic compounds can be successfully treated without the formation of dioxines, suggesting that SCWO is useful as an alternative technology to the conventional incineration process.

We have reported a very rare case of a patient with callosal disconnection syndrome due to acute disseminated enchephalomyelitis (ADEM). A 54-year-old right-handed woman developed sudden consciousness disturbance and fever after 2 weeks when she had common cold. She did not have a history of stuttering. On admission, the neurological finding showed consciousness disturbance, and exaggerated muscle stretch reflex in four extremities without meningeal irritation. The cerebrospinal fluid examination revealed the cell counts of 273/mm3, the protein of 348 mg/dl and the myelin basic protein 18.3 pg/ml. The brain MRI demonstrated a focal high signal intensity in the right cerebellar peduncle, right temporal lobe, left occipital lobe and corpus callosum on the T2-weighted and FLAIR images. The lesion of corpus callosum was the trunk and splenium, sparing the dorsal side of splenium. Her diagnosis was ADEM. The steroid pulse therapy (metylpredinisolone 1 g/day for 3 days) improved the consciousness disturbance. After 6 weeks from the onset, the neuropsycological examination was performed. The remarkable findings included pure alexia without color naming defects, the acquired stuttering and one-way disturbance of somesthetic transfer from the left hand to the right. This patient may contribute to the study of functional localization of the corpus callosum.