Rescattering effects in charmless B_{u,d,s} to P P decays

We study the final-state interaction (FSI) effects in charmless B_{u,d,s} to PP decays. We consider a FSI approach with both short- and long-distance contributions, where the former are from in-elastic channels and are contained in factorization amplitudes, while the latter are from the residual rescattering among PP states. Flavor SU(3) symmetry is used to constrain the residual rescattering S-matrix. We fit to all available data on the CP-averaged decay rates and CP asymmetries, and make predictions on unmeasured ones. Our main results are as follows: (i) Results are in agreement with data in the presence of FSI. (ii) For B decays, the pi^+pi^- and pi^0pi^0 rates are suppressed and enhanced respectively by FSI. (iii) The FSI has a large impact on direct CP asymmetries of many modes. (iv) The deviation (Delta A) between A(B{bar}^0 to K^-pi^+) and A(B^-to K^-\pi^0) can be understood in the FSI approach. (v) Sizable and complex color-suppressed tree amplitudes, which are crucial for the large \pi^0\pi^0 rate and Delta A, are generated through exchange rescattering. The correlation of the ratio B(pi^0pi^0)/B(pi^+pi^-) and Delta A is studied. (vi) The B^- to pi^-pi^0 direct CP violation is very small and is not affected by FSI. (vii) Several B_s decay rates are enhanced. In particular, the eta'eta' branching ratio is enhanced to the level of 1.0X10^{-4}, which can be checked experimentally. (viii) Time-dependent CP asymmetries S in B_{d,s} decays are studied. CP asymmetries in these modes will be useful to test the SM.Comment: 33 pages, 6 figures, version to appear in Phys. Rev.

Structural Characterization of Rapid Thermal Oxidized Si\u3csub\u3e1−x−y\u3c/sub\u3eGe\u3csub\u3ex\u3c/sub\u3eC\u3csub\u3ey\u3c/sub\u3e Alloy Films Grown by Rapid Thermal Chemical Vapor Deposition

The structural properties of as-grown and rapid thermal oxidized Si1−x−yGexCy epitaxial layers have been examined using a combination of infrared, x-ray photoelectron, x-ray diffraction, secondary ion mass spectroscopy, and Raman spectroscopy techniques. Carbon incorporation into the Si1−x−yGexCy system can lead to compressive or tensile strain in the film. The structural properties of the oxidized Si1−x−yGexCy film depend on the type of strain (i.e., carbon concentration) of the as-prepared film. For compressive or fully compensated films, the oxidation process drastically reduces the carbon content so that the oxidized films closely resemble to Si1−xGex films. For tensile films, two broad regions, one with carbon content higher and the other lower than that required for full strain compensation, coexist in the oxidized films

Limb bone scaling in hopping diprotodonts and quadrupedal artiodactyls

Bone adaptation is modulated by the timing, direction, rate, and magnitude of mechanical loads. To investigate whether frequent slow, or infrequent fast, gaits could dominate bone adaptation to load, we compared scaling of the limb bones from two mammalian herbivore clades that use radically different high-speed gaits, bipedal hopping and quadrupedal galloping. Forelimb and hindlimb bones were collected from 20 artiodactyl and 15 diprotodont species (body mass M 1.05 - 1536 kg) and scanned in clinical computed tomography or X-ray microtomography. Second moment of area (Imax) and bone length (l) were measured. Scaling relations (y = axb) were calculated for l vs M for each bone and for Imax vs M and Imax vs l for every 5% of length. Imax vs M scaling relationships were broadly similar between clades despite the diprotodont forelimb being nearly unloaded, and the hindlimb highly loaded, during bipedal hopping. Imax vs l and l vs M scaling were related to locomotor and behavioural specialisations. Low-intensity loads may be sufficient to maintain bone mass across a wide range of species. Occasional high-intensity gaits might not break through the load sensitivity saturation engendered by frequent low-intensity gaits

THE IN VITRO AND EX VIVO EFFECT OF PHYLLANTHUS NIRURI METHANOL EXTRACT ON HEPATIC UDP-GLUCURONYLTRANSFERASE ENZYME ACTIVITY IN STZ-INDUCED DIABETIC SPRAGUE DAWLEY RATS

Objective: The aim of the study was to investigate the in vitro and ex vivo (acute and sub-chronic doses) effect of Phyllanthus niruri methanol extract (PNME) on the microsomal UDP-glucuronyltransferase (UGT) enzyme activity in streptozotocin (STZ)-induced diabetic young female Sprague Dawley (SD) rats. Methods: Young female SD rats were induced type I diabetes mellitus using STZ (60 mg/kg i. v.). The in vitro study was performed on a microsomal fraction of diabetic rat livers using PNME in doses of (0.01 µg, 1 µg and 10 µg)/ml. While ex vivo studies were performed on the microsomal fraction of diabetic rats using PNME in doses of 500, 1000, 2000 and 5000 mg/kg p. o. for acute ex vivo study (one-day treatment) and 100, 500 and 2000 mg/kg/day p. o. for sub-chronic one (daily dose for two weeks). p-nitrophenol (p-NP), was used as a marker substrate for UGT enzyme activity and analyzed using the spectrophotometer to determine UGT enzyme activity. Results: The in vitro result showed that, there is no significant effect of the three concentrations of PNME versus control on UGT activity in the microsomal fraction of diabetic young female SD rat livers, while for ex vivo study, the result showed that UGT activity in the microsomal fraction of diabetic young female SD rats significantly and dose-independently increased at doses 1000, 2000 and 5000 mg/kg p. o in acute study (all p<0.05 vs control). However, no significant effect of PNME has been seen in the three doses used in the sub-chronic study. Conclusion: The three different concentrations of PNME have no significant effect as compared to control on UGT activity in the in vitro study. However, ex vivo study showed significant and dose-independent increased in UGT activity at doses 1000, 2000, and 5000 mg/kg p. o in acute study (all P<0.01 vs control), but no significant effect on sub-chronic study

Control of Multi-level Voltage States in a Hysteretic SQUID Ring-Resonator System

In this paper we study numerical solutions to the quasi-classical equations of motion for a SQUID ring-radio frequency (rf) resonator system in the regime where the ring is highly hysteretic. In line with experiment, we show that for a suitable choice of of ring circuit parameters the solutions to these equations of motion comprise sets of levels in the rf voltage-current dynamics of the coupled system. We further demonstrate that transitions, both up and down, between these levels can be controlled by voltage pulses applied to the system, thus opening up the possibility of high order (e.g. 10 state), multi-level logic and memory.Comment: 8 pages, 9 figure

Sampling rare fluctuations of height in the Oslo ricepile model

We have studied large deviations of the height of the pile from its mean value in the Oslo ricepile model. We sampled these very rare events with probabilities of order $10^{-100}$ by Monte Carlo simulations using importance sampling. These simulations check our qualitative arguement [Phys. Rev. E, {\bf 73}, 021303, 2006] that in steady state of the Oslo ricepile model, the probability of large negative height fluctuations $\Delta h=-\alpha L$ about the mean varies as $\exp(-\kappa {\alpha}^4 L^3)$ as $L \to \infty$ with $\alpha$ held fixed, and $\kappa > 0$.Comment: 7 pages, 8 figure

Phenomenological Consequences of Right-handed Down Squark Mixings

The mixings of $d_R$ quarks, hidden from view in Standard Model (SM), are naturally the largest if one has an Abelian flavor symmetry. With supersymmetry (SUSY) their effects can surface via $\tilde d_R$ squark loops. Squark and gluino masses are at TeV scale, but they can still induce effects comparable to SM in $B_d$ (or $B_s$) mixings, while $D^0$ mixing could be close to recent hints from data. In general, CP phases would be different from SM, as may be indicated by recent B Factory data. Presence of non-standard soft SUSY breakings with large $\tan\beta$ could enhance $b\to d\gamma$ (or $s\gamma$) transitions.Comment: Version to appear in Phys. Rev. Let

Andreev Probe of Persistent Current States in Superconducting Quantum Circuits

Using the extraordinary sensitivity of Andreev interferometers to the superconducting phase difference associated with currents, we measure the persistent current quantum states in superconducting loops interrupted by Josephson junctions. Straightforward electrical resistance measurements of the interferometers give continuous read-out of the states, allowing us to construct the energy spectrum of the quantum circuit. The probe is estimated to be more precise and faster than previous methods, and can measure the local phase difference in a wide range of superconducting circuits.Comment: Changes made in light of referees comments; to appear in PR

Rapid generation of fully relativistic extreme-mass-ratio-inspiral waveform templates for LISA data analysis

The future space mission LISA will observe a wealth of gravitational-wave sources at millihertz frequencies. Of these, the extreme-mass-ratio inspirals of compact objects into massive black holes are the only sources that combine the challenges of strong-field complexity with that of long-lived signals. Such signals are found and characterized by comparing them against a large number of accurate waveform templates during data analysis, but the rapid generation of such templates is hindered by computing the $\sim10^3$-$10^5$ harmonic modes in a fully relativistic waveform. We use order-reduction and deep-learning techniques to derive a global fit for these modes, and implement it in a complete waveform framework with hardware acceleration. Our high-fidelity waveforms can be generated in under $1\,\mathrm{s}$, and achieve a mismatch of $\lesssim 5\times 10^{-4}$ against reference waveforms that take $\gtrsim 10^4$ times longer. This marks the first time that analysis-length waveforms with full harmonic content can be produced on timescales useful for direct implementation in LISA analysis algorithms.Comment: 6 pages, 3 figure

Selective laser sintering of hydroxyapatite reinforced polyethylene composites for bioactive implants and tissue scaffold development

Selective laser sintering (SLS) has been investigated for the production of bioactive implants and tissue scaffolds using composites of high-density polyethylene (HDPE) reinforced with hydroxyapatite (HA) with the aim of achieving the rapid manufacturing of customized implants. Single-layer and multilayer block specimens made of HA-HDPE composites with 30 and 40 vol % HA were sintered successfully using a CO2 laser sintering system. Laser power and scanning speed had a significant effect on the sintering behaviour. The degree of particle fusion and porosity were influenced by the laser processing parameters, hence control can be attained by varying these parameters. Moreover, the SLS processing allowed exposure of HA particles on the surface of the composites and thereby should provide bioactive products. Pores existed in the SLS-fabricated composite parts and at certain processing parameters a significant fraction of the pores were within the optimal sizes for tissue regeneration. The results indicate that the SLS technique has the potential not only to fabricate HA-HDPE composite products but also to produce appropriate features for their application as bioactive implants and tissue scaffolds