1,261 research outputs found
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Measurement of the Xi(-)(b) and Omega(-)(b) baryon lifetimes
No full textUsing a data sample of pp collisions corresponding to an integrated luminosity of 3 fb−1, the Ξ−b and Ω−b baryons are reconstructed in the Ξ−b → J/ψΞ− and Ω−b → J/ψΩ− decay modes and their lifetimes measured to be
τ(Ξ−b) = 1.55+0.10−0.09 (stat) ± 0.03 (syst) ps,
τ(Ω−b) = 1.54+0.26−0.21 (stat) ± 0.05 (syst) ps.
These are the most precise determinations to date. Both measurements are in good agreement with previous experimental results and with theoretical predictions
The role of poly (ADP-ribose) polymerase-1 in the celluar response to several marine-derived compounds:
No full textPARP-1 is a multi-functional protein that is involved in many DNA-dependent genomic processes under normal and pathophysiological conditions. It is well characterized as a DNA damage detector and responds by catalytic production and attachment of polymers of ADP-ribose (PAR) to nuclear protein targets, facilitating the chromatin changes that are a prerequisite to DNA repair. In this study, we tested whether PARP-1 is involved in the cellular response to Yondelis®, Zalypsis®, PSL1, and PSL2, novel chemotherapeutic agents with putative DNA damage- and transcription-targeted activities. We observed a dose-dependent activation of PARP-1 catalytic activity following treatment with all four compounds, while PARP-1 protein levels remained unchanged. Interestingly, cells derived from PARP-1 null mice were significantly sensitized to the agents, yet, with respect to Yondelis®, only moderate DNA damage was observed which was repaired with equal efficiency by both PARP-1 wildtype and PARP-1 null cells. While the mechanism of sensitization is unclear, it is of interest to determine whether inhibition of PARP in human cells could sensitize cells to the four agents. Initial in vivo experiments testing this prediction using MX-1 breast carcinoma xenografts treated with Yondelis® alone or in combination with the PARP-1 inhibitor DIQ, demonstrate an additive effect between these two compounds with regard to tumor volume inhibition and tumor growth delay. However, corresponding in vitro experiments failed to corroborate this observation. The effects of PARP-1 on the transcription of genes impacting drug sensitivity, as well as the cyto-protective role of PARP-1 independent of its catalytic function are of interest to direct future efforts to clarify the mechanism of PARP-1-mediated sensitivity to the four agents. Taken together, these data suggest that PARP-1 plays an important role in the protection of cells to Yondelis®, Zalypsis®, PSL1, and PSL2, and suggest that PARP-1 status may determine the sensitivity or resistance of cells treated with these agents.M.S.Includes bibliographical references (p. 45-53)by Brijesh B. Pate
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
Evaluation of the Tauc Method for Optical Absorption Edge Determination: ZnO Thin Films as a Model System
No full textOne of the most frequently used methods for characterizing thin films is UV-Vis absorption. The near-edge region can be fitted to a simple expression in which the intercept gives the band-gap and the fitting exponent identifies the electronic transition as direct or indirect. (See Tauc et al., Physica Status Solidi, 1966; these are often called “Tauc” plots.) While the technique is powerful and simple, the accuracy of the fitted band-gap result is seldom stated or known. We tackle this question by refitting a large number of Tauc plots from the literature and look for trends. Nominally pure zinc oxide (ZnO) was chosen as a material with limited intrinsic deviation from stoichiometry and which has been widely studied. Our examination of the band gap values and their distribution leads to a discussion of some experimental factors that can bias the data and lead to either smaller or larger apparent values than would be expected. Finally, an easily evaluated figure-of-merit is defined that may help guide more accurate Tauc fitting. For samples with relatively sharper Tauc plot shapes, the population yields Eg (ZnO) as 3.276 +/- 0.033 eV, in good agreement with data for single crystalline material.This is the accepted version of the following article: Viezbicke, B. D., Patel, S., Davis, B. E. and Birnie, D. P. (2015), Evaluation of the Tauc method for optical absorption edge determination: ZnO thin films as a model system. Phys. Status Solidi B, 252: 1700–1710, which has been published in final form at https://dx.doi.org/10.1002/pssb.201552007.Peer reviewe
Effects of Superheat and Solute Additions on the Grain Size in Binary Copper Alloys
No full text© The Author(s) 2019. By utilizing data from the literature, we examine the effects of superheat and solute additions on the grain size (as measured by columnar grain length) in binary copper alloys. Our investigation provides support for an Arrhenius-like behavior of the superheat on the grain size. We also find a correlation between the columnar grain length at a constant degree of superheat and the variation of the reciprocal of the true growth restriction factor (1/Q) with P, Mg, Mn, Pb, and Sn solute additions to be a power of law of 1/3, which gave a better fit than a linear one.EPSRC (UK
Experimental investigations on the effect of process parameters with the use of minimum quantity solid lubrication in turning
No full textMorphological and optical data of AgNW embedded transparent conductive layer
No full textAbstractIn this data article, morphological and optical data of AgNW encapsulated between ITO layers are presented to get insights into our article (DOI:10.1016/j.solmat.2016.04.038; Hong-Sik Kim, Pankaj Yadav, Malkeshkumar Patel, Hyunki Kim, Kavita Pandey, Joondong Kim, 2016) [1]. SEM images for the formation of AgNWs networks by number of spin coating are also presented. SEM photographs showing the surface morphologies before and after rapid thermal treatment of prepared samples have been presented. Apart from morphological data set, optical characteristics of this type of samples are given. The comparison plots of optical reflectance from AgNW encapsulated between ITO layers and bare ITO are given between the wavelength ranges from 300 to 1100nm. At the end, transmittance and reflectance curves of native glass substrates used in this study are presented
Psychological, social and welfare interventions for psychological health and well-being of torture survivors
No full textThis is the protocol for a review and there is no abstract. The objectives are as follows: Primary objective 1. To assess beneficial and adverse effects of psychological, social and welfare interventions versus no treatment for the reduction of psychological distress in torture survivors. Secondary objectives 2. To describe the quality and generalisability of the studies evaluating the effects of these treatment approaches on torture survivors, and specifically: • to provide an objective assessment of risk of bias in these studies; • to describe the specific populations evaluated in studies of torture survivors (including demographics, torture experiences and psychological status); • to describe the variety of interventions that have been evaluated in these populations; and • to describe the outcomes evaluated in these intervention studies
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
- …
