81,931 research outputs found
Determinations of |V_ub| and |V_cb| from measurements of B -> X_u,c\ell\nu differential decay rates
Methods are described in the framework of light-cone expansion which allow
one to determine the Cabibbo-Kobayashi-Maskawa matrix elements |V_ub| and
|V_cb| from measurements of the differential decay rates as a function of the
scaling variables in the inclusive semileptonic decays of B mesons. By these
model-independent methods the dominant hadronic uncertainties can be avoided
and the B -> X_u\ell\nu decay can be very efficiently differentiated from the B
-> X_c\ell\nu decay, which may lead to precise determinations of |V_ub| and
|V_cb|.Comment: 11 pages, 2 figures, version as published in Mod. Phys. Lett. A, more
discussion, references added, title chang
Ligand induced cleavage and nuclear localization of the rice XA21 immune receptor
The rice XA21 receptor confers immunity to the Gram-negative bacterial pathogen, _Xanthomonas oryzae_ pv. _oryzae_ (_Xoo_) upon recognition of the conserved microbial signature AxY^S^22. Here, we demonstrate that the intracellular kinase domain of XA21 translocates to the nucleus upon AxY^S^22-mediated perception and that this translocation event is required for XA21-mediated immunity
Strongly Nonlinear Waves in 3D Phononic Crystals
Three dimensional phononic crystal ("sonic vacuum" without prestress) was assembled from 137 vertical cavities arranged in hexagonal pattern in Silicone matrix filled with stainless steel spheres. This system has unique strongly nonlinear properties with respect to wave propagation inherited from nonlinear Hertz type elastic contact interaction. Trains of strongly nonlinear solitary waves excited by short duration impact were investigated. Solitary wave with speed below sound speed in the air and reflection from the boundary of two "sonic vacuums" were detected
Relationship between spin squeezing and single-particle coherence in two-component Bose-Einstein condensates with Josephson coupling
We investigate spin squeezing of a two-mode boson system with a Josephson
coupling. An exact relation between the squeezing and the single-particle
coherence at the maximal-squeezing time is discovered, which provides a more
direct way to measure the squeezing by readout the coherence in atomic
interference experiments. We prove explicitly that the strongest squeezing is
along the axis, indicating the appearance of atom number-squeezed state.
Power laws of the strongest squeezing and the optimal coupling with particle
number are obtained based upon a wide range of numerical simulations.Comment: 4 figures, revtex4, new refs. are adde
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