2,294 research outputs found
Mass of the B_c Meson in Three-Flavor Lattice QCD
We use lattice QCD to predict the mass of the meson. We use the MILC
Collaboration's ensembles of lattice gauge fields, which have a quark sea with
two flavors much lighter than a third. Our final result is
. The first error bar is a sum in quadrature
of statistical and systematic uncertainties, and the second is an estimate of
heavy-quark discretization effects.Comment: 4 pages, 3 figures; shorten to fit in PRL; published versio
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Surgery for Dupuytrenâs contracture of the fingers (Review)
Background - Dupuytren's disease is a benign fibroproliferative disorder that causes the fingers to be drawn into the palm via formation of new tissue under the glabrous skin of the hand. This disorder causes functional limitations, but it can be treated through a variety of surgical techniques. As a chronic condition, it tends to recur.
Objectives - To assess the benefits and harms of different surgical procedures for treatment of Dupuytren's contracture of the index, middle, ring and little fingers
The interpretation of mu suppression as an index of mirror neuron activity: past, present and future
Mu suppression studies have been widely used to infer the activity of the human mirror neuron system (MNS) in a number of processes, ranging from action understanding, language, empathy and the development of autism spectrum disorders (ASDs). Although mu suppression is enjoying a resurgence of interest, it has a long history. This review aimed to revisit muâs past, and examine its recent use to investigate MNS involvement in language, social processes and ASDs. Mu suppression studies have largely failed to produce robust evidence for the role of the MNS in these domains. Several key potential shortcomings with the use and interpretation of mu suppression, documented in the older literature and highlighted by more recent reports, are explored here
Predictions from Lattice QCD
In the past year, we calculated with lattice QCD three quantities that were
unknown or poorly known. They are the dependence of the form factor in
semileptonic decay, the decay constant of the meson, and the
mass of the meson. In this talk, we summarize these calculations, with
emphasis on their (subsequent) confirmation by experiments.Comment: v1: talk given at the International Conference on QCD and Hadronic
Physics, Beijing, June 16-20, 2005; v2: poster presented at the XXIIIrd
International Symposium on Lattice Field Theory, Dublin, July 25-3
Tula orthohantavirus nucleocapsid protein is cleaved in infected cells and may sequester activated caspase-3 during persistent infection to suppress apoptosis
The family Hantaviridae mostly comprises rodent-borne segmented negative-sense RNA viruses, many of which are capable of causing devastating disease in humans. In contrast, hantavirus infection of rodent hosts results in a persistent and inapparent infection through their ability to evade immune detection and inhibit apoptosis. In this study, we used Tula hantavirus (TULV) to investigate the interplay between viral and host apoptotic responses during early, peak and persistent phases of virus infection in cell culture. Examination of early-phase TULV infection revealed that infected cells were refractory to apoptosis, as evidenced by the complete lack of cleaved caspase-3 (casp-3C) staining, whereas in non-infected bystander cells casp-3C was highly abundant. Interestingly, at later time points, casp-3C was abundant in infected cells, but the cells remained viable and able to continue shedding infectious virus, and together these observations were suggestive of a TULV-associated apoptotic block. To investigate this block, we viewed TULV-infected cells using laser scanning confocal and wide-field deconvolution microscopy, which revealed that TULV nucleocapsid protein (NP) colocalized with, and sequestered, casp-3C within cytoplasmic ultrastructures. Consistent with casp-3C colocalization, we showed for the first time that TULV NP was cleaved in cells and that TULV NP and casp-3C could be co-immunoprecipitated, suggesting that this interaction was stable and thus unlikely to be solely confined to NP binding as a substrate to the casp-3C active site. To account for these findings, we propose a novel mechanism by which TULV NP inhibits apoptosis by spatially sequestering casp-3C from its downstream apoptotic targets within the cytosol
Light-Driven H2 Evolution and CâC or CâO Bond Hydrogenation by Shewanella oneidensis : A Versatile Strategy for Photocatalysis by Nonphotosynthetic Microorganisms
Photocatalytic chemical synthesis by coupling abiotic photosensitizers to purified enzymes provides an effective way to overcome the low conversion efficiencies of natural photosynthesis while exploiting the high catalytic rates and selectivity of enzymes as renewable, earth-abundant electrocatalysts. However, the selective synthesis of multiple products requires more versatile approaches and should avoid the time-consuming and costly processes of enzyme purification. Here we demonstrate a cell-based strategy supporting light-driven H2 evolution or the hydrogenation of CâC and CâO bonds in a nonphotosynthetic microorganism. Methylviologen shuttles photoenergized electrons from water-soluble photosensitizers to enzymes that catalyze H2 evolution and the reduction of fumarate, pyruvate, and CO2 in Shewanella oneidensis. The predominant reaction is selected by the experimental conditions, and the results allow rational development of cell-based strategies to harness natureâs intrinsic catalytic diversity for selective light-driven synthesis of a wide range of products
Calculating the QED correction to the hadronic vacuum polarisation on the lattice
Isospin-breaking corrections to the hadron vacuum polarization component of the anomalous magnetic moment of the muon are needed to ensure the theoretical precision of gΌ - 2 is below the experimental precision. We describe the status of our work calculating, using lattice QCD, the QED correction to the light and strange connected hadronic vacuum polarization in a Dashen scheme. We report results using physical N f = 2 + 1 + 1 HISQ ensembles at three lattice spacings and three heavier-than-light valence quark masses
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