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排序方式: 共有567条查询结果,搜索用时 109 毫秒
561.
Choi SK Olsen SL Adachi I Aihara H Aulchenko V Aushev T Aziz T Bakich AM Balagura V Bedny I Bitenc U Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Dalseno J Danilov M Dash M Eidelman S Gabyshev N Golob B Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kang JH Katayama N Kawai H Kawasaki T Kichimi H Kim HO Kim SK Kim YJ 《Physical review letters》2008,100(14):142001
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. 相似文献
562.
Iwabuchi M Nakao M Adachi I Arinstein K Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Belous K Bhardwaj V Bitenc U Bozek A Bracko M Browder TE Chen A Chen WT Cheon BG Cho IS Choi Y Dalseno J Dash M Drutskoy A Eidelman S Fujikawa M Gabyshev N Ha H Haba J Hayasaka K Hazumi M Heffernan D Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Ishino H Itoh R Iwasaki M Kah DH Kaji H Kang JH Kawai H Kawasaki T Kichimi H Kim HJ Kim HO Kim YI Kim YJ Kinoshita K Korpar S Krizan P Krokovny P 《Physical review letters》2008,101(4):041601
We report on a search for the doubly Cabibbo suppressed decay B+-->D*+pi0, based on a data sample of 657x10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signal and set an upper limit of B(B+-->D*+pi0)<3.6x10(-6) at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B-->D*pi decay amplitudes, r<0.051, at the 90% confidence level. 相似文献
563.
Ushiroda Y Sumisawa K Taniguchi N Adachi I Aihara H Arinstein K Aushev T Bahinipati S Bakich AM Balagura V Barberio E Belous K Bitenc U Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Cho IS Choi Y Dalseno J Dash M Eidelman S Epifanov D Gabyshev N Golob B Ha H Haba J Hara K Hara T Hayasaka K Hazumi M Heffernan D Hokuue T Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Ishino H Itoh R Iwasaki Y Kah DH Kang JH Kawai H Kawasaki T Kichimi H Kim YJ Kinoshita K 《Physical review letters》2008,100(2):021602
We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively. 相似文献
564.
Nakahama Y Sumisawa K Adachi I Aihara H Aushev T Bakich AM Balagura V Barberio E Bedny I Belous K Bitenc U Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Cho IS Choi Y Dalseno J Dash M Drutskoy A Eidelman S Gabyshev N Golob B Ha H Haba J Hara K Hara T Hayasaka K Hazumi M Heffernan D Hoshi Y Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kaji H Kang JH Katayama N Kawai H Kawasaki T Kichimi H Kim HJ Kim HO 《Physical review letters》2008,100(12):121601
We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst). 相似文献
565.
Pratigyan Dash Sasmita Samal Gyanendra Prasad Panda Anna Maria Piras Mamoni Dash 《Macromolecular bioscience》2023,23(11):2300211
Osteosarcoma (OS) is a malignant tumor, fatal for pediatric patients who do not respond to chemotherapy, alternative therapies and drugs can provide better outcomes. Zoledronic acid (Zol) belonging to the class of bisphosphonates (BPs) has a direct antitumor ability to prevent Ras GTPases modification and stimulate apoptosis. Despite advances in maintaining balance in skeletal events and direct anticancer properties, Zol causes cytotoxicity to normal healthy pre-osteoblast cells, hampering mineralization and differentiation. The study reports the preparation and evaluation of a nanoformulation that can diminish the existing drawbacks of native Zol. The cytotoxic effect is evaluated on bone cancer cells and healthy bone cells with three different cell lines namely, K7M2 (mouse OS cell line), SaOS2 (human OS cell line), and MC3T3E1 (healthy cell counterpart). It is observed that Zol nanoformulation is uptaken more (95%) in K7M2 whereas in MC3T3E1, the percent population internalizing nanoparticles (NPs) is 45%. Zol has a sustained release of 15% after 96 h from the NP which leads to a rescuing effect on the normal pre-osteoblast cells. In conclusion, it can be stated that Zol nanoformulation can be used as a good platform for a sustained release system with minimum side effects to normal bone cells. 相似文献
566.
Ritapa Chaudhuri Thumpati Prasanth Dr. Jyotirmayee Dash 《Angewandte Chemie (International ed. in English)》2023,62(7):e202219003
Herein, we demonstrate for the first time that noncanonical DNA can direct macrocyclization-like challenging reactions to synthesize gene modulators. The planar G-quartets present in DNA G-quadruplexes (G4s) provide a size complementary reaction platform for the bio-orthogonal macrocyclization of bifunctional azide and alkyne fragments over oligo- and polymerization. G4s immobilized on gold-coated magnetic nanoparticles have been used as target templates to enable easy identification of a selective peptidomimetic macrocycle. Structurally similar macrocycles have been synthesized to understand their functional role in the modulation of gene function. The innate fluorescence of the in situ formed macrocycle has been utilized to monitor its cellular localization using a G4 antibody and its in cell formation from the corresponding azide and alkyne fragments. The successful execution of in situ macrocyclization in vitro and in cells would open up a new dimension for target-directed therapeutic applications. 相似文献
567.