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71.
Aushev T Iwasaki Y Abe K Abe K Adachi I Aihara H Akatsu M Asano Y Aziz T Bahinipati S Bakich AM Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi Y Chuvikov A Danilov M Dash M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Hastings NC Hayasaka K Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou S Hou WS Iijima T Imoto A Inami K Ishikawa A 《Physical review letters》2004,93(20):201802
We report a search for CP-violating asymmetry in B0-->D(*+/-)D-/+ decays. The analysis employs two methods of B0 reconstruction: full and partial. In the full reconstruction method all daughter particles of the B0 are required to be detected; the partial reconstruction technique requires a fully reconstructed D- and only a slow pion from the D(*+)-->D0pi(+)(slow) decay. From a fit to the distribution of the time interval corresponding to the distance between two B meson decay points we calculate the CP-violating parameters and find the significance of nonzero CP asymmetry to be 2.7 standard deviations. 相似文献
72.
Kobayashi T Kawai H Suzuki T Kawanishi T Hayakawa T 《Rapid communications in mass spectrometry : RCM》2004,18(10):1156-1160
This report describes an enhancement of the signal intensities of proteins and peptides in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). When alpha-cyano-4-hydroxycinnamic acid (CHCA) premixed with human transferrin (Tf) was used as a matrix, the signal intensity of insulin was amplified to more than ten times that of the respective control in CHCA without Tf. The detection limit of insulin was 0.39 fmol on-probe in the presence of Tf, while it was 6.3 fmol in the absence of Tf. The signal intensity of insulin was also enhanced when the CHCA matrix was premixed with proteins other than Tf (80 kDa), such as horse ferritin (20 kDa), bovine serum albumin (BSA, 66 kDa), or human immunoglobulin G (150 kDa). The optimum spectrum of insulin was obtained when the added amount of protein was in the range 0.26-0.62 pmol, regardless of the molecular weight of the added protein. Tf and BSA outperformed the other tested proteins, as determined by improvements in the resulting spectra. When the mass spectra of several peptides and proteins were recorded in the presence of Tf or BSA, the signal intensities of large peptides such as glucagon were enhanced, though those of smaller peptides were not enhanced. In addition, the signal enhancement achieved with Tf and BSA was more pronounced for the proteins, including cytochrome C, than for the large peptides. This enhancement effect could be applied to improve the sensitivity of MALDI-TOFMS to large peptides and proteins. 相似文献
73.
Fang F Hojo T Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Golob B Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Huang HC Igaki T Igarashi Y Iijima T Inami K 《Physical review letters》2003,90(7):071801
We report measurements of branching fractions for charged and neutral B-->eta(c)K decays where the eta(c) meson is reconstructed in the K(0)(S)K+/-pi(-/+), K+K-pi(0), K(*0)K-pi(+), and pp; decay channels. The neutral B0 channel is a CP eigenstate and can be used to measure the CP violation parameter sin(2phi(1). We also report the first observation of the B0-->eta(c)K(*0) mode. The results are based on an analysis of 29.1 fb(-1) of data collected by the Belle detector at KEKB. 相似文献
74.
Zegers RG Sumihama M Ahn DS Ahn JK Akimune H Asano Y Chang WC Daté S Ejiri H Fujimura H Fujiwara M Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kohri H Kumagai N Makino S Matsumura T Matsuoka N Mibe T Miwa K Miyabe M Miyachi Y Morita M Muramatsu N Nakano T Niiyama M Nomachi M Ohashi Y Ooba T Ohkuma H Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu H Sugaya Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T Yoshimura M Yosoi M 《Physical review letters》2003,91(9):092001
Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献
75.
Kawai K Takada T Nagai T Cai X Sugimoto A Fujitsuka M Majima T 《Journal of the American Chemical Society》2003,125(52):16198-16199
The hole transfer causes the long-lived charge-separated state in DNA during the photosensitized one-electron oxidation of DNA. The combination of the transient absorption measurement and DNA damage quantification by HPLC clearly demonstrated that the yield of the DNA damage correlates well with the lifetime of the charge-separated state. 相似文献
76.
Kim H Ralph J Lu F Ralph SA Boudet AM MacKay JJ Sederoff RR Ito T Kawai S Ohashi H Higuchi T 《Organic & biomolecular chemistry》2003,1(2):268-281
Peroxidase/H2O2-mediated radical coupling of 4-hydroxycinnamaldehydes produces 8-O-4-, 8-5-, and 8-8-coupled dehydrodimers as has been documented earlier, as well as the 5-5-coupled dehydrodimer. The 8-5-dehydrodimer is however produced kinetically in its cyclic phenylcoumaran form at neutral pH. Synthetic polymers produced from mixtures of hydroxycinnamaldehydes and normal monolignols provide the next level of complexity. Spectral data from dimers, oligomers, and synthetic polymers have allowed a more substantive assignment of aldehyde components in lignins isolated from a CAD-deficient pine mutant and an antisense-CAD-downregulated transgenic tobacco. CAD-deficient pine lignin shows enhanced levels of the typical benzaldehyde and cinnamaldehyde end-groups, along with evidence for two types of 8-O-4-coupled coniferaldehyde units. The CAD-downregulated tobacco also has higher levels of hydroxycinnamaldehyde and hydroxybenzaldehyde (mainly syringaldehyde) incorporation, but the analogous two types of 8-O-4-coupled products are the dominant features. 8-8-Coupled units are also clearly evident. There is clear evidence for coupling of hydroxycinnamaldehydes to each other and then incorporation into the lignin, as well as for the incorporation of hydroxycinnamaldehyde monomers into the growing lignin polymer. Coniferaldehyde and sinapaldehyde (as well as vanillin and syringaldehyde) co-polymerize with the traditional monolignols into lignins and do so at enhanced levels when CAD-deficiency has an impact on the normal monolignol production. The implication is that, particularly in angiosperms, the aldehydes behave like the traditional monolignols and should probably be regarded as authentic lignin monomers in normal and CAD-deficient plants. 相似文献
77.
Ishii A Kawai T Tekura K Oshida H Nakayama J 《Angewandte Chemie (International ed. in English)》2001,40(10):1924-1926
78.
A reductive transmetalation of the pi-allylpalladium(II) complexes, generated in situ from a catalytic amount of a palladium(0) complex and a variety of allylic substrates, with indium(I) salts proceeded smoothly in various solvents, providing a new route for allylindium(III) reagents. 相似文献
79.
1.5-mum emissions from Nd:YAG, Nd:YVO(4), and LiNdP(4) O>(12) microchip lasers pumped by laser diodes have been observed. These coherent emissions are attributed to the effect of high-energy modified lattice vibration owing to the existence of Nd ions as well as to stimulated intracavity Raman scattering enhanced by the microchip configuration. A four-wave mixing process involving two lasing fields and a Stokes field was identified as the generator of new adjacent 1.5-mu;m emission. 相似文献
80.
Affects of microwave bandwidth on the high-charge-states of ion beams extracted from a conventional minimum-B-geometry ECR ion source are first demonstrated. The high-charge-state intensities, produced with broadband microwave radiation are observed to be factors ?2 than those produced with narrow bandwidth microwave radiation at the same power level. 相似文献