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We developed a mass spectrometric soil-gas flux measurement system using a portable high-resolution multi-turn time-of-flight mass spectrometer, called MULTUM, and we combined it with an automated soil-gas flux chamber for the continuous field measurement of multiple gas concentrations with a high temporal resolution. The developed system continuously measures the concentrations of four different atmospheric gases (NO2, CH4, CO2, and field soil–atmosphere flux measurements of greenhouse gases (NO2, O2) ranging over 6 orders of magnitude at one time using a single gas sample. The measurements are performed every 2.5 min with an analytical precision (2 standard deviations) of ±34 ppbv for NO2; ±170 ppbv, CH4; ±16 ppmv, CO2; and ±0.60 vol %, O2 at their atmospheric concentrations. The developed system was used for the continuous field soil–atmosphere flux measurements of greenhouse gases (NO2, CH4, and CO2) and O2 with a 1 h resolution. The minimum quantitative fluxes (2 standard deviations) were estimated via a simulation as 70.2 µgNm-2h-1 for NO2; 139 µgCm-2h-1, CH4; 11.7 mg C m−2 h−1, CO2; and 9.8 g O2 m−2 h−1, O2. The estimated minimum detectable fluxes (2 standard deviations) were 17.2 µgNm-2h-1 for NO2; 35.4 µgCm-2h-1, CH4; 2.6 mg C m−2 h−1, CO2; and 2.9 g O2 m−2 h−1, O2. The developed system was deployed at the university farm of the Ehime University (Matsuyama, Ehime, Japan) for a field observation over 5 d. An abrupt increase in NO2 flux from 70 to 682 µgNm-2h-1 was observed a few hours after the first rainfall, whereas no obvious increase was observed in CO2 flux. No abrupt NO2 flux change was observed in succeeding rainfall events, and the observed temporal responses at the first rainfall were different from those observed in a laboratory experiment. The observed differences in temporal flux variation for each gas component show that gas production processes and their responses for each gas component in the soil are different. The results of this study indicate that continuous multiple gas concentration and flux measurements can be employed as a powerful tool for tracking and understanding underlying biological and physicochemical processes in the soil by measuring more tracer gases such as volatile organic carbon, reactive nitrogen, and noble gases, and by exploiting the broad versatility of mass spectrometry in detecting a broad range of gas species.

Severe winter haze accompanied by high concentrations of fine particulate matter (PM2.5) occurs frequently in the North China Plain and threatens public health. Organic matter (OM) and sulfate are recognized as major components of PM2.5, while atmospheric models often fail to predict their high concentrations during severe winter haze due to incomplete understanding of secondary aerosol formation mechanisms. By using a novel combination of single-particle mass spectrometry and an optimized ion chromatography method, here we show that hydroxymethanesulfonate (HMS), formed by the reaction between formaldehyde (HCHO) and dissolved SO2 in aerosol water, is ubiquitous in Beijing during winter. The HMS concentration and the molar ratio of HMS to sulfate increased with the deterioration of winter haze. High concentrations of precursors (SO2 and HCHO) coupled with low oxidant levels, low temperature, high relative humidity, and moderately acidic pH facilitate the heterogeneous formation of HMS, which could account for up to 15 % of OM in winter haze and lead to up to 36 % overestimates of sulfate when using traditional ion chromatography. Despite the clean air actions having substantially reduced SO2 emissions, the HMS concentration and molar ratio of HMS to sulfate during severe winter haze increased from 2015 to 2016 with the growth in HCHO concentration. Our findings illustrate the significant contribution of heterogeneous HMS chemistry to severe winter haze in Beijing, which helps to improve the prediction of OM and sulfate and suggests that the reduction in HCHO can help to mitigate haze pollution.

The laser-induced breakdown threshold intensities of high-pressure gasses as a function of pressure were measured. The breakdown threshold intensity of N 2 gas was found to be much higher than those of He and Ar gasses at a gas pressure of 2.0 MPa. It was also 7 to 11 times higher than that of aerosol droplets, and is sufficiently high to allow the number density of droplets to be measured in a high-pressure aerosol by laser-induced breakdown.

Twenty-seven patients received boron neutron capture therapy during craniotomy at our research reactor from 1991 to 1999. This is a form of intra-operative radiation therapy, which uses neutrons from a nuclear reactor. There are three additional major problems to anaesthetists: boron neutron capture therapy must be given beside the nuclear reactor, with no hospital facilities; neutrons cannot be shielded effectively by ordinary protectors; and neutrons are detrimental to metal devices and especially to electrical appliances. Boron neutron capture therapy has been adopted as an effective therapy for glioblastoma/astrocytoma, but special considerations are required for anaesthesia.

A new type of column packed with polystyrene gels which have a broad pore size distribution in a particle (henceforth referred to as the multipore column) was developed, and its performance was compared with the so-called linear column (henceforth referred to as the mixed-bed column). The chromatogram of the epoxy resin (Epikote 1009) on the multipore column showed a monomodal distribution, but the chromatogram on the mixed-bed column showed the inflection on the chromatogram at the molecular mass of about 10,000 as polystyrene equivalent. There was a big difference in the pore size distributions of gels packed in the two types of columns; the pore size distribution of the multipore column showed the trapezoid, while that of the mixed-bed column had sharp maxima for pores with a diameter of 0.08 μm. This difference in the pore size distribution may be the main reason for the inflection phenomenon, though the calibration curves of these two types of columns were almost the same. The multipore colu...

Alcohol dehydrogenase-I (ADH-I) derived from horse liver stimulated IgM production by human-human hybridoma, HB4C5 cells and lymphocytes. The IPSF activity of ADH-I was suppressed by coexistence of short DNA whose chain length is less than 200 base pairs (bp) and fibrous DNA in a dose-dependent manner. These DNA preparations completely inhibited the IPSF activity at the concentration of 250 mug/ml and 1.0 mg/ml, respectively. DNA sample termed long DNA whose average chain length is 400-7000 bp slightly stimulated IPSF activity at 0.06 mug/ml. However, long DNA suppressed IPSF activity by half at 1.0 mg/ml. The laser confocal microscopic analysis had revealed that ADH-I was incorporated by HB4C5 cells. The uptake of ADH-I was strongly inhibited by short DNA and fibrous DNA. However, long DNA did not suppress the internalization of ADH-I into HB4C5 cells. These findings indicate that short DNA and fibrous DNA depress IPSF activity of ADH-I by inhibiting the internalization of this enzyme. According to the gel-filtration analysis using HPLC, ADH-I did not directly interact with short DNA. It is expected from these findings that short DNA influences HB4C5 cells to suppress the internalization of ADH-I. Moreover, these facts also strongly suggest that ADH-I acts as IPSF after internalization into the cell.

We have proposed a digital optoelectronic parallel computing system for implementing the genetic algorithm by using the JOP prototypes. Two kinds of the optical parallel image broadcasting processor used in the system are experimentally evaluated.

Twenty-seven patients received boron neutron capture therapy during craniotomy at our research reactor from 1991 to 1999. This is a form of intra-operative radiation therapy, which uses neutrons from a nuclear reactor. There are three additional major problems to anaesthetists: boron neutron capture therapy must be given beside the nuclear reactor, with no hospital facilities; neutrons cannot be shielded effectively by ordinary protectors; and neutrons are detrimental to metal devices and especially to electrical appliances. Boron neutron capture therapy has been adopted as an effective therapy for glioblastoma/astrocytoma, but special considerations are required for anaesthesia.

We have experienced massive blood loss (80,000 g) during living-related donor liver transplantation (LRDLT) of a 14-year old girl with biliary atresia. As available homologous blood was not sufficient, we transfused autologous blood (13,400 ml) during operation. Although immunosuppressant was administered to the patient, severe infection did not occur for 10 days after the operation. Cold ischemia time of the graft liver was about 16 hr, but her postoperative liver function was well-maintained. The case suggests that intraoperative autologus blood transfusion is effective if homologous blood is insufficient during LRDLT.

Microregional mechanical measurements of a poly[methylmethacrylate) film can be made by a combined probe/measurement laser system, as represented in the picture. The localized nature of the laser systems allow quantification of the degree of expansion and contraction processes, as well as the glass-rubber transition. Such nondestructive techniques lead to the elucidation of polymer morphological dynamics.

We have recently shown that endothelin-1 (ET-1) activates two types of Ca2+-permeable nonselective cation channels (designated NSCC-1 and NSCC-2) and store-operated Ca2+ channel (SOCC). These channels can be pharmacologically discriminated using Ca2+ channel blockers such as SKF 96365 and LOE 908. Here we characterized Ca2+ entry channels involved in ET-1-induced contractions of rat thoracic aortic rings and increases in the intracellular free Ca2+ concentration ([Ca2+]i) of single smooth muscle cells using these blockers. LOE 908 or a blocker of voltage-operated Ca2+ channel nifedipine had no effect on the contractions and increases in [Ca2+]i induced by thapsigargin or ionomycin, whereas SKF 96365 abolished them. The contractions and increases in [Ca2+]i induced by ET-1 depended on extracellular Ca2+ but were resistant to nifedipine. The responses to lower concentrations (or =0.1 nM) of ET-1 were abolished by either SKF 96365 or LOE 908. The responses to higher concentrations (or = 1 nM) were abolished by SKF 96365, but were partially resistant to LOE 908. SKF 96365 inhibited the LOE 908-resistant contractions induced by higher concentrations of ET-1 with IC50 values similar to those for contractions induced by thapsigargin or ionomycin. These results show that the contractions and increases in [Ca2+]i of rat aortic smooth muscles at lower concentrations of ET-1 involve only one Ca2+ entry channel which is sensitive to SKF 96365 and LOE 908 (NSCC-2), whereas those at higher concentrations of ET-1 involve another Ca2+ entry channel which is sensitive to SKF 96365 but resistant to LOE 908 (SOCC) in addition to the former channel.

Photopolymers based on the triazeno chromophore group (-N=N-N{lt}) have been developed. The absorption properties can be tailored for a specific irradiation wavelength. The photochemical exothermic decomposition yields high energetic gaseous products which are not contaminating the surface. The polymer can be structured with high resolution. No debris has been found around the etched corners. Maximum ablation rates of about 3 micrometer/pulse were achieved due to the dynamic absorption behavior (bleaching during the pulse). No physical or chemical modifications of the polymer surface could be detected after irradiation at the tailored absorption wavelength, whereas irradiation at different wavelengths resulted in modified (physical and chemical) surfaces.

Immunoglobulin production stimulating activity of alcohol dehydrogenase [EC 1.1.1.1] was assessed. Alcohol dehydrogenase-I (ADH-I) derived from horse liver stimulated IgM production by human-human hybridoma, HB4C5 cells producing human lung cancer specific monoclonal IgM. IgM production of HB4C5 cells was enhanced more than 6 fold by the addition of ADH-I at 400 microg/ml under serum-free condition. However, yeast derived ADHs, such as ADH-II and -III were ineffective to accelerate immunoglobulin production of the hybridoma line. These results imply that the immunoglobulin production stimulating effect of ADH-I is irrelevant to its enzymatic function, and defined as a novel feature of ADH-I. This enzyme also stimulated IgM and IgG production by human peripheral blood lymphocytes 2.9 fold and 1.4 fold, respectively. This fact suggests that ADH-I stimulates immunoglobulin production not only by specific hybridoma cell line, but also by non-specific immunoglobulin producers.

Hemophilia B is a hereditary disease caused by defects in coagulation factor IX. Accumulation of sequence data in the hemophilia B database makes it possible to study this disease at the molecular level. The most common mutations reported in the database are amino acid substitutions. Activity of factor IX in a patient's blood depends on a position of the substitution and combination of original and substituting amino acids. We have developed a method to estimate the effects of amino acid substitutions in factor IX of hemophilia B patients. We adopted two kinds of scores: (1) amino acid homology matrices, and (2) distances obtained from physical-chemical properties of amino acids. We found that: (1) the distance obtained from molecular volume shows the highest correlation with factor IX activity among four physical-chemical properties of amino acids, and (2) Dayhoff's 250PAM matrix gives the highest correlation among three homology matrices. We performed a multiple regression analysis for the estimation of factor IX activity by using four amino acid parameters and obtained a distance matrix, which gives the multiple correlation coefficient 0.6. Hemophilia is a hereditary, X-linked, recessive hemorrhagic disorder. About three-fourths of patients with hemophilia have the A type which is due to deficient factor VIII activity. The B type is less frequent than the A type and is due to deficient factor IX activity. Factor IX is a vitamin K dependent plasma protein that participates in the middle phase of blood coagulation. The entire nucleotide sequence of the factor IX gene was reported by Yoshitake et. al. There have been reported a variety of defects in the factor IX gene from hemophilia B patients, and these are summarized in the hemophilia B database. The effects of amino acid substitutions on the activities of factor IX depends on two factors. One is the combination of native and hemophilic amino acids, the differences of physical-chemical properties of the amino acids. Another is the position of mutation in factor IX protein. In this study, we analyzed missense mutations in the database described with factor IX activity values. Among them, the cases with double mutations were excluded from the analysis, leaving 255 cases. The number of unique mutations are 127. We have introduced distances between 20 amino acids by using the following four physical-chemical properties: (1) Molecular volume, (2)Hydropathy, (3) Polar requirement, and (4) Isoelectric point. We also adopted three homology matrices. These matrices are symmetric and composed of 20 x 20 elements, corresponding to amino acid pairs: (1)Dayhoff's 250 PAM matrix, (2) SCM (Structure-derived Correlation Matrix), and (3) SSM (Structure Superposition Matrix). This analysis shows that the highest correlation with factor á¿ activity is 0.47 given by molecular volume. The second one is 0.4 of Dayhoff's 250 PAM matrix. The multiple regression analysis, using four physicalchemical properties of amino acids, gives a correlation coefficient of 0.60. The amino acid distance obtained by the multiple regression analysis provides a useful measure to estimate the severity of the disease caused by a missense mutation. For example, if the distance between native and hemophilic amino acids is less than 1.5, the ratios of severe cases (activity is less than or equal to 1% of the normal), moderate cases (less than or equal to 4%), and mild cases are 67%, 27% and 6%, respectively.

A bench-scale plant for producing hydrogen has been constructed on the basis of the thermochemical water-decomposition process, UT-3, consisting of Br, Ca and Fe compounds. This plant is named MASCOT (Model Apparatus for Studying Cyclic Operation in Tokyo) and is designed to be capable of producing 3 l/h of gaseous hydrogen at standard conditions. During several test runs, the continuous production of hydrogen was successfully achieved. In the present paper, the construction of the MASCOT plant is described.

A new cascade model has been constructed and applied to high-energy heavy-ion collisions, where the emphasis is placed on a systematic study of nuclear collective motion. The model provides a time-dependent microscopic description of nuclear cascade collisions which takes into account some important aspects of the colliding system. The calculated results agree consistently with the experimental data, which otherwise have been interpreted as evidence for collective motion.

The 3H(p,n)3He charge exchange reaction is studied within the framework of [3N+N]‐cluster model in the energy region corresponding to the excitation energy of 4He from 20 to 35 MeV. Various kinds of polarization data are sensitive to the positions of the excited states. Therefore we can obtain useful informations about the level structure of 4He from this reaction.