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121.
Chen KF Hara K Hazumi M Higuchi T Miyabayashi K Nakahama Y Sumisawa K Tajima O Ushiroda Y Yusa Y Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Balagura V Banerjee S Barberio E Barbero M Bay A Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Garmash A 《Physical review letters》2007,98(3):031802
We present improved measurements of CP-violation parameters in B(0) --> phiK(0), eta(')K(0), KS(0)KS(0)KS(0) decays based on a sample of 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We obtain sin2phi1(eff)=+0.64+/-0.10(stat)+/-0.04(syst) for B(0) --> eta(')K(0), +0.50+/-0.21(stat)+/-0.06(syst) for B(0) --> phiK(0), and +0.30+/-0.32(stat)+/-0.08(syst) for B(0) --> KS(0)KS(0)KS(0) decays. We have observed CP violation in the B(0) --> eta(')K(0) decay with a significance of 5.6 standard deviations. We also perform an improved measurement of CP asymmetries in B(0) --> J/psiK(0) decays and obtain sin2phi1=+0.642+/-0.031(stat)+/-0.017(syst). 相似文献
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We introduce a new high accuracy second-order finite-difference time-domain (FDTD) algorithm based on non-standard finite differences, and use it to investigate light propagation in subwavelength structures such as photonic crystals. 相似文献
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A Bioorthogonal Small‐Molecule‐Switch System for Controlling Protein Function in Live Cells 下载免费PDF全文
Dr. Peng Liu Abram Calderon Dr. Georgios Konstantinidis Dr. Jian Hou Dipl. Stephanie Voss Dr. Xi Chen Fu Li Soumya Banerjee Dr. Jan‐Erik Hoffmann Christiane Theiss Dr. Leif Dehmelt Dr. Yao‐Wen Wu 《Angewandte Chemie (International ed. in English)》2014,53(38):10049-10055
Chemically induced dimerization (CID) has proven to be a powerful tool for modulating protein interactions. However, the traditional dimerizer rapamycin has limitations in certain in vivo applications because of its slow reversibility and its affinity for endogenous proteins. Described herein is a bioorthogonal system for rapidly reversible CID. A novel dimerizer with synthetic ligand of FKBP′ (SLF′) linked to trimethoprim (TMP). The SLF′ moiety binds to the F36V mutant of FK506‐binding protein (FKBP) and the TMP moiety binds to E. coli dihydrofolate reductase (eDHFR). SLF′‐TMP‐induced heterodimerization of FKBP(F36V) and eDHFR with a dissociation constant of 0.12 μM . Addition of TMP alone was sufficient to rapidly disrupt this heterodimerization. Two examples are presented to demonstrate that this system is an invaluable tool, which can be widely used to rapidly and reversibly control protein function in vivo. 相似文献
125.
Kaushik Dey Shebeeb Kunjattu H. Anurag M. Chahande Rahul Banerjee 《Angewandte Chemie (International ed. in English)》2020,59(3):1161-1165
Covalent organic frameworks (COFs) have attracted attention due to their ordered pores leading to important industrial applications like storage and separation. Combined with their modular synthesis and pore engineering, COFs could become ideal candidates for nanoseparations. However, the fabrication of these microcrystalline powders as continuous, crack‐free, robust films remains a challenge. Herein, we report a simple, slow annealing strategy to construct centimeter‐scale COF films ( Tp‐Azo and Tp‐TTA ) with micrometer thickness. The as‐synthesized films are porous (SABET=2033 m2 g?1 for Tp‐Azo ) and chemically stable. These COFs have distinct size cut‐offs (ca. 2.7 and ca. 1.6 nm for Tp‐Azo and Tp‐TTA , respectively), which allow the size‐selective separation of gold nanoparticles. Unlike, other conventional membranes, the durable structure of the COF films allow for excellent recyclability (up to 4 consecutive cycles) and easy recovery of the gold nanoparticles from the solution. 相似文献
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Johannes Maschita Tanmay Banerjee Gkcen Savasci Frederik Haase Christian Ochsenfeld Bettina V. Lotsch 《Angewandte Chemie (International ed. in English)》2020,59(36):15750-15758
Covalent organic frameworks (COFs) are an extensively studied class of porous materials, which distinguish themselves from other porous polymers in their crystallinity and high degree of modularity, enabling a wide range of applications. COFs are most commonly synthesized solvothermally, which is often a time‐consuming process and restricted to well‐soluble precursor molecules. Synthesis of polyimide‐linked COFs (PI‐COFs) is further complicated by the poor reversibility of the ring‐closing reaction under solvothermal conditions. Herein, we report the ionothermal synthesis of crystalline and porous PI‐COFs in zinc chloride and eutectic salt mixtures. This synthesis does not require soluble precursors and the reaction time is significantly reduced as compared to standard solvothermal synthesis methods. In addition to applying the synthesis to previously reported imide COFs, a new perylene‐based COF was also synthesized, which could not be obtained by the classical solvothermal route. In situ high‐temperature XRPD analysis hints to the formation of precursor–salt adducts as crystalline intermediates, which then react with each other to form the COF. 相似文献
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Tanmoy Banerjee 《Nonlinear dynamics》2012,68(4):565-573
The present paper reports an inductor-free realization of Chua??s circuit, which is designed by suitably cascading a single amplifier biquad based active band pass filter with a Chua??s diode. The system has been mathematically modeled with three-coupled first-order autonomous nonlinear differential equations. It has been shown through numerical simulations of the mathematical model and hardware experiments that the circuit emulates the behaviors of a classical Chua??s circuit, e.g., fixed point behavior, limit cycle oscillation, period doubling cascade, chaotic spiral attractors, chaotic double scrolls and boundary crisis. The occurrence of chaotic oscillation has been established through experimental power spectrum, and quantified with the dynamical measure like Lyapunov exponents. 相似文献