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31.
Hajime Kawakami Makio C. Honda Shuichi Watanabe Toshiro Sino 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(2):461-468
We carried out time-series observations of 210Po and 210Pb radioactivity in the western North Pacific Ocean. The sinking fluxes of particulate organic carbon (POC) in the mesopelagic zone were estimated from 210Po radioactivity during several seasons in the subarctic and subtropical regions of the western North Pacific. The seasonal changes of POC fluxes at a depth of 400 m were larger in the subarctic region than in the subtropical region. The annual mean POC flux at a depth of 400 m was larger in the subarctic region (57 mgC m?2 day?1) than in the subtropical region (36 mgC m?2 day?1). The annual mean of the e-ratio (the ratio of POC flux to primary productivity) in the subarctic region (18 %) was about twice the e-ratio in the subtropical region (10 %). These results imply that the efficiency of the biological pump is larger in the subarctic region than in the subtropical region of the western North Pacific. 相似文献
32.
Uncovering the Stoichiometry of Pyrococcus furiosus RNase P,a Multi‐Subunit Catalytic Ribonucleoprotein Complex,by Surface‐Induced Dissociation and Ion Mobility Mass Spectrometry
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Xin Ma Lien B. Lai Stella M. Lai Akiko Tanimoto Prof. Mark P. Foster Prof. Vicki H. Wysocki Prof. Venkat Gopalan 《Angewandte Chemie (International ed. in English)》2014,53(43):11483-11487
We demonstrate that surface‐induced dissociation (SID) coupled with ion mobility mass spectrometry (IM‐MS) is a powerful tool for determining the stoichiometry of a multi‐subunit ribonucleoprotein (RNP) complex assembled in a solution containing Mg2+. We investigated Pyrococcus furiosus (Pfu) RNase P, an archaeal RNP that catalyzes tRNA 5′ maturation. Previous step‐wise, Mg2+‐dependent reconstitutions of Pfu RNase P with its catalytic RNA subunit and two interacting protein cofactor pairs (RPP21?RPP29 and POP5?RPP30) revealed functional RNP intermediates en route to the RNase P enzyme, but provided no information on subunit stoichiometry. Our native MS studies with the proteins showed RPP21?RPP29 and (POP5?RPP30)2 complexes, but indicated a 1:1 composition for all subunits when either one or both protein complexes bind the cognate RNA. These results highlight the utility of SID and IM‐MS in resolving conformational heterogeneity and yielding insights on RNP assembly. 相似文献
33.
Letters in Mathematical Physics - We construct explicitly strong generators of the affine $$\mathcal {W}$$-algebra $$\mathcal {W}^{K_0-N}(\mathfrak {sl}_N, f_{sub})$$ of subregular type A.... 相似文献
34.
Kenji Yoshikawa Miki Shimizu Toshiro Matsumura Akio Sakuragawa 《International journal of environmental analytical chemistry》2018,98(8):789-798
Capillary zone electrophoresis with indirect UV detection was developed for the simultaneous analysis of inorganic anions and organic acids using a mixed solution of 2,6-pyridinedicarboxylic acid and cetyltrimethylammonium hydroxide as the background electrolyte (BGE). The parameters which influence the separation, such as indirect UV detection wavelength, BGE conditions, applied voltage and extraction conditions were investigated. Thirteen inorganic anions and organic acids were detected within 20 min. The calibration curves of each analyte were linear with correlation coefficients greater than 0.991. The relative standard deviations (n = 10) of the peak areas ranged from 0.6% to 3.3%. The detection limits for these species ranged from 0.4 to 1.4 mg/L at a signal-to-noise ratio of 3. The recovery rate of each analyte was more than 80% under optimised extraction conditions, except for nitrite. The proposed method was applied towards the analysis of inorganic anions and organic acids in the atmospheric particulate matter using an Andersen sampler. The particle size of the particulate matter was determined, but not the size of the anions. 相似文献
35.
36.
The class of exponential tilts of convolution equivalent distributions is determined. As a corollary, the local subexponentiality
of one-sided infinitely divisible distributions is characterized. It is applied to the subexponentiality of the densities
of a self-decomposable distribution and its Lévy measure. Bondesson’s conjecture on the density of the Lévy measure of a lognormal
distribution is solved as an example. Results of Denisov et al. on the distributions of random sums are extended to the two-sided
case. Finally, the local subexponentiality of the distribution of the supremum of a random walk is characterized. 相似文献
37.
Haino T Araki H Fujiwara Y Tanimoto Y Fukazawa Y 《Chemical communications (Cambridge, England)》2002,(18):2148-2149
A new class of fullerene sensors based on calix[5]arenes has produced the highly sensitive detection of C60 and C70. 相似文献
38.
We study the correlation between CP violation in neutrino oscillations and leptogenesis in the framework with two heavy Majorana neutrinos and three light neutrinos. Among three unremovable CP phases, a heavy Majorana phase contributes to leptogenesis. We show how the heavy Majorana phase contributes to Jarlskog determinant J as well as neutrinoless double beta decay by identifying a low energy CP-violating phase which signals the CP-violating phase for leptogenesis. For some specific cases of the Dirac mass term of neutrinos, a direct relation between lepton number asymmetry and J is obtained. We also study the effect coming from the phases which are not related to leptogenesis. 相似文献
39.
We study the size dependence of the nonlinear response of weakly confined excitons for the size region beyond the long wavelength approximation regime. The observed degenerate-four-wave mixing signal of GaAs thin layers exhibits an anomalous size dependence, where the signal is resonantly enhanced at a particular thickness region. The theoretical analysis elucidates that this enhancement is due to the size-resonant enhancement of the internal field with a spatial structure relevant to the nondipole-type excitonic state. These results establish the formerly proposed new type of size dependence of nonlinear response due to the nonlocality induced double resonance. 相似文献
40.
Shigehiro Morikawa Toshiro Inubushi Kan Takahashi Hisanari Ishii Shino Shigemori 《Magnetic resonance imaging》1996,14(10):1197-1204
The relationships among tissue edema, lactate accumulation, and intracellular pH in middle cerebral artery (MCA)-occluded rats were investigated with multiecho 1H magnetic resonance imaging and spatially resolved metabolic images constructed by 1H and 31P nuclear magnetic resonance (NMR) chemical shift imaging (CSI). For the effective and sensitive detection of NMR signals from the brain, outer volume suppression (OVS), reduced k-space sampling and proton irradiation were incorporated into the CSI sequences. The consecutive three measurements of calculated T2 image, lactate image, and pH image which were required for 3.75 h were repeated for four cycles of 1–16 h after MCA occlusion. Tissue edema and lactate accumulation in the infarcted region were gradually and consistently increased during the 15-h observation period. In contrast, severe acidosis was already detected on the first pH image (2–4.7 h after MCA occlusion); thereafter, the degree of acidosis became milder and showed no further progression. The dissociation between the time courses of the lactate accumulation and pH decrease was clearly demonstrated by the NMR metabolic images. Acid-base balance in cerebral infarction might be affected not only by lactate production but also by complicated interactions with tissue edema and some other factors. 相似文献