Platelet-activating factor receptor (PAFR)-deficient mice developed a more severe obese state characterized by higher body mass (~25%) and epididymal fat mass (~55%) with age than that of wild-type (WT) littermates. PAFR-deficient mice did not show changes in the expression of critical genes involved in anabolic and catabolic metabolism in adipose, liver, and muscle tissues between 6 and 36 wk. However, a 38-81% reduction in β3/β1-adrenergic receptor (AR) and uncoupling protein 1 (UCP1) mRNA and protein levels was observed in the interscapular brown adipose tissue (BAT) of PAFR-deficient mice. Whereas a single injection of the β3-adrenergic agonist, CL-316,243 (25 μg/kg) increased temperatures in the brown fat and rectums of WT mice, this increase in temperature was markedly suppressed in PAFR-deficient mice. Acetyl-CoA:lyso-platelet-activating factor (PAF) acetyltransferase, which is involved in PAF biosynthesis, and the PAF receptor were predominantly localized in BAT macrophages, whereas brown adipocytes possessed the enzyme and functional PAF receptors. The stimulation of brown adipocytes by PAF induced the expression of β3-AR mRNA and protein (1.5- and 1.9-fold, respectively), but not that of UCP1. These results indicate that obesity in PAFR-deficient mice resulted from impaired BAT activity and suggest that the antiobese function of PAF occurs through β3-AR/UCP1 expression in BAT.

A preliminary study of the corrosion films of stainless steel SUS304 was carried out by X-ray photoemission spectroscopy for supercritical water having no oxidant or reactant. The corrosion films produced by the supercritical water at 450°C and 50 MPa were compared with those by anodic polarization in H 2 SO 4 aqueous solution. The chemical states in the films were determined by factor analysis of Fe, Cr, and Ni 2p X-ray photoelectron spectra. Factor analysis of the passivated SUS304 surface was successfully carried out using four reference spectra, Fe metal, Fe 3 O 4 , Fe 2 O 3 , and FeOOH, with careful treatment excluding wüstite Fe 1−x O phase from the standpoint of thermochemistry. In the surface treated by supercritical water, the ratio of iron and nickel increased even when compared to the bulk composition of SUS304 and the major component of nickel was attributed to NiFe 2 O 4 . In contrast, the content of chromium decreased remarkably. This was explained by effective removal of CrO 4 2− and its protonated form, HCrO 4 − , which are predicted in the Pourbaix diagram prepared for chromium in supercritical water ͑450°C and 50 MPa͒.Supercritical water ͑Ͼ647 K and Ͼ22.1 MPa͒ for decomposing nonflammable organic materials present in low-level radioactive waste has been extensively studied. 1-4 Although materials highly resistive to supercritical water are desirable, corrosion effect of the supercritical water is not well understood. In view of the practical use, stainless steels are preferable. However, it has been questioned whether stainless steels are tough to high temperatures of the supercritical water and corrosive species in it. An example of the corrosive condition is hydrogen peroxide in 2% H 2 SO 4 + 2% H 2 O 2 at 400°C and 28.5 MPa, which is used to oxidize cation-exchange resin.This preliminary study of the corrosion films of stainless steel SUS304 was done by X-ray photoelectron spectroscopy ͑XPS͒ for supercritical water having no oxidant or reductant. The corrosion films by the supercritical water at 450°C and 50 MPa were compared with those by anodic polarization in H 2 SO 4 aqueous solution. The chemical states in the films were determined by factor analysis of Fe, Cr, and Ni 2p XPS spectra. The results were discussed with Pourbaix diagrams. ExperimentalPreparation of SUS304 specimens for treatment with supercritical water.-Specimens with dimensions of 10 ϫ 5 ϫ 1 mm were used. In order to investigate the passivation layer formed in each treatment, after the rolling plane of the samples was finished with no. 8000 emery paper, they were washed twice with ethanol in an ultrasonic cleaner. Each sample was then weighed and loaded into a supercritical batch-wise reactor made of hastelloy C-22, whose nominal inside volume was 10.8 cm 3 , 1,2 with 3 mL of water. In order to control the temperature of the reactor, five cartridge heaters were attached to the reactor vessel and a thermocouple was used to measure the temperature inside the reactor. The reaction was carried out at a temperature and pressure ...

913A phenomenological study is given of the (possible) violation of CP and CPT symmetries in the A"'-K" system. Special attention is paid to the problem of phase ambiguity and phase convention.Mixing parameters and decay amplitudes are parametrized in a rephasing invariant way, and the well-known parameters 7'/+-and 7' /oo describing 2Jr modes as well as various leptonic asymmetries are expressed in terms of these parameters. The parameters E and L1 characterizing mixing between ) in terms of the strangeness eigenstates I~> and IK 0 ) and the CP eigenstates IK, 0 ) and IK2°>, their transformation property under CP, T and CPT operations is examined and the problem of phase ambiguity is discussed. Formulae relevant for a phenomenological analysis of 2;r decay modes at

A series of power spectral analyses for a thermal subcritical reactor system driven by a pulsed 14 MeV neutron source was carried out at Kyoto University Critical Assembly (KUCA), to determine the promptneutron decay constant of the accelerator-driven system (ADS). The cross-power spectral density between time-sequence signal data of two neutron detectors was composed of a familiar continuous reactor noise component and many delta-function-like peaks at the integral multiple of pulse repetition frequency. The prompt-neutron decay constant inferred from the reactor noise component of the cross-power spectral density was consistent with that obtained by a pulsed neutron experiment. However, the reactor noise component of the auto-power spectral density of each detector was hidden by a white chamber noise in the higher-frequency range and this feature resulted in a considerable underestimation of the decay constant. For several runs with a low pulse-repetition frequency, furthermore, we attempted to infer the decay constant from point data of the delta-function-like peaks. The analysis for a run under a slightly subcritical state resulted in the consistent decay constant; however, those for other runs under significantly subcritical states underestimated the decay constant. Considering the contribution of a spatially higher mode to the point data, the above underestimation was solved to obtain the consistent decay constant. While the Feynman-α formula for a pulsed neutron source is too complicated to be fitted directly to variance-to-mean ratio data, the present analysis on frequency domain is much simpler and the conventional formula based on the first-order reactor transfer function is available for fitting to power spectral density data.

Large negative reactivity of a subcritical system driven by a pulsed 14 MeV neutron source has been measured in the Kyoto University Critical Assembly. The subcriticality of the accelerator-driven system (ADS) ranged in effective multiplication factor roughly from 0.98 to 0.92, which corresponded to an operational range of an actual ADS proposed by Japan Atomic Energy Agency. As the measurement technique, pulsed neutron method, power spectral analysis for pulsed neutron source, accelerator-beam trip method were employed. From neutron count decay data obtained by the pulsed neutron experiment, not only the promptneutron decay constant of fundamental mode but also a higher spatial mode could be derived. The subcriticality was also determined from the fundamental decay constant. The measured cross-power spectral density consisted of a familiar correlated reactor-noise component and many uncorrelated delta-functionlike peaks at the integral multiple of pulse repetition frequency. The fundamental prompt-neutron decay constant, i.e., the subcriticality determined from the latter uncorrelated peaks was consistent with that obtained by the above pulsed neutron experiment. However, the magnitude of the former correlated component was reduced with an increase in the subcriticality and eventually this component became almost white at deeply subcritical state ranging in the multiplication factor under 0.95. Consequently, the determination of the decay constant from the correlated component was impossible under such a subcritical state. As data analysis method for the beam trip experiment, both the conventional integral count method and the least-squares inverse kinetics method (LSIKM) were employed. The LSIKM analysis led to the consistent subcriticality with that obtained by the pulsed neutron experiment, while the integral count method significantly underestimated the subcriticality. This underestimation originated from a residual background count, which was maintained after the beam trip. The LSIKM was mostly not influenced by such a slight count rate.