346 research outputs found
Glueball enhancements in p(gamma,VV)p through vector meson dominance
Double vector meson photoproduction, p(gamma, G -> VV)p, mediated by a scalar
glueball G is investigated. Using vector meson dominance (VMD) and
Regge/pomeron phenomenology, a measureable glueball enhancement is predicted in
the invariant VV = rho rho and omega omega mass spectra. The scalar glueball is
assumed to be the lightest physical state on the daughter pomeron trajectory
governing diffractive vector meson photoproduction. In addition to cross
sections, calculations for hadronic and electromagnetic glueball decays, G -> V
V' (V,V'= rho, omega, phi, gamma), and gamma_v V -> G transition form factors
are presented based upon flavor universality, VMD and phenomenological
couplings from phi photoproduction analyses. The predicted glueball decay
widths are similar to an independent theoretical study. A novel signature for
glueball detection is also discussed
Relative effectiveness of robot-assisted and standard laparoscopic prostatectomy as alternatives to open radical prostatectomy for treatment of localised prostate cancer : a systematic review and mixed treatment comparison meta-analysis
© 2013 The Authors. BJU International © 2013 BJU International.Peer reviewedPublisher PD
Exotic and excited-state radiative transitions in charmonium from lattice QCD
We compute, for the first time using lattice QCD methods, radiative
transition rates involving excited charmonium states, states of high spin and
exotics. Utilizing a large basis of interpolating fields we are able to project
out various excited state contributions to three-point correlators computed on
quenched anisotropic lattices. In the first lattice QCD calculation of the
exotic 1-+ eta_c1 radiative decay, we find a large partial width Gamma(eta_c1
-> J/psi gamma) ~ 100 keV. We find clear signals for electric dipole and
magnetic quadrupole transition form factors in chi_c2 -> J/psi gamma,
calculated for the first time in this framework, and study transitions
involving excited psi and chi_c1,2 states. We calculate hindered magnetic
dipole transition widths without the sensitivity to assumptions made in model
studies and find statistically significant signals, including a non-exotic
vector hybrid candidate Y_hyb? -> eta_c gamma. As well as comparison to
experimental data, we discuss in some detail the phenomenology suggested by our
results and the extent to which it mirrors that of quark potential models and
make suggestions for the interpretation of our results involving exotic quantum
numbered states
Development of anthropometric characteristics in professional Rugby League players: Is there too much emphasis on the pre-season period?
This is an Accepted Manuscript of an article published by Taylor & Francis in European Journal of Sport Science on 04/12/2019, available online: http://www.tandfonline.com/doi/full/10.1080/17461391.2019.1695953Rugby League is a team sport requiring players to experience large impact collisions, thus requiring high amounts of muscle
mass. Many players (academy and senior) strive to increase muscle mass during the pre-season, however, quantification of
changes during this period have not been thoroughly investigated. We therefore assessed changes in body-composition
using Dual X-Ray Absorptiometry (DXA) in eleven academy players over three successive pre-seasons and ninety-three
senior players from four different European Super League clubs prior to, and at the end of, a pre-season training period.
There was no meaningful change in lean mass of the academy players during any of the pre-season periods (year 1 = 72.3
± 7.1–73.2 ± 7.2kg; ES 0.05, year 2 = 74.4 ± 6.9–75.5 ± 6.9kg; ES 0.07, year 3 = 75.9 ± 6.7–76.8 ± 6.6kg; ES 0.06) with
small changes only occurring over the three-year study period (72.3–75.9kg; ES = 0.22). Senior players showed trivial
changes in all characteristics during the pre-season period (total mass = 95.1–95.0kg; ES −0.01, lean mass = 74.6–75.1kg;
ES 0.07, fat mass = 13.6–12.9kg; ES −0.17, body fat percentage = 14.8–14.1%; ES −0.19). These data suggest that academy players need time to develop towards profiles congruent with senior players. Moreover, once players reach senior
level, body-composition changes are trivial during the pre-season and therefore teams may need to individualise training
for players striving to gain muscle mass by reducing other training loads
PGC‑1α alternative promoter (Exon 1b) controls augmentation of total PGC‑1α gene expression in response to cold water immersion and low glycogen availability
This investigation sought to determine whether post-exercise cold water immersion and low glycogen availability, separately
and in combination, would preferentially activate either the Exon 1a or Exon 1b Peroxisome proliferator-activated
receptor gamma coactivator 1-alpha (PGC-1α) promoter. Through a reanalysis of sample design, we identified that the
systemic cold-induced augmentation of total PGC-1α gene expression observed previously (Allan et al. in J Appl Physiol
123(2):451–459, 2017) was largely a result of increased expression from the alternative promoter (Exon 1b), rather than
canonical promoter (Exon 1a). Low glycogen availability in combination with local cooling of the muscle (Allan et al. in
Physiol Rep 7(11):e14082, 2019) demonstrated that PGC-1α alternative promoter (Exon 1b) expression continued to rise at
3 h post-exercise in all conditions; whilst, expression from the canonical promoter (Exon 1a) decreased between the same
time points (post-exercise–3 h post-exercise). Importantly, this increase in PGC-1α Exon 1b expression was reduced compared
to the response of low glycogen or cold water immersion alone, suggesting that the combination of prior low glycogen and
CWI post-exercise impaired the response in gene expression versus these conditions individually. Data herein emphasise the
influence of post-exercise cooling and low glycogen availability on Exon-specific contro
Masses and widths of scalar-isoscalar multi-channel resonances from data analysis
Peculiarities of obtaining parameters for broad multi-channel resonances from
data are discussed analyzing the experimental data on processes
in the channel in a
model-independent approach based on analyticity and unitarity and using an
uniformization procedure. We show that it is possible to obtain a good
description of the scattering data from the threshold to 1.89 GeV with
parameters of resonances cited in the PDG tables as preferred. However, in this
case, first, representation of the background is unsatisfactory;
second, the data on the coupled process are not well
described even qualitatively above 1.15 GeV when using the resonance parameters
from the only scattering analysis. The combined analysis of these
coupled processes is needed, which is carried out satisfactorily. Then both
above-indicated flaws, related to the analysis of solely the
-scattering, are cured. The most remarkable change of parameters with
respect to the values of only scattering analysis appears for the mass
of the which is now in some accordance with the Weinberg prediction
on the basis of mended symmetry and with an analysis using the large-
consistency conditions between the unitarization and resonance saturation. The
obtained -scattering length in case when we restrict to the
analysis of the scattering or consider so-called A-solution (with a
lower mass and width of meson) agrees well with prediction of chiral
perturbation theory (ChPT) and with data extracted at CERN by the NA48/2
Collaboration from the analysis of the decay and by the DIRAC
Collaboration from the measurement of the lifetime.Comment: 21 pages, 3 figures, 6 table
Post-exercise cold-water immersion modulates skeletal muscle PGC-1α mRNA expression in immersed and non-immersed limbs: evidence of systemic regulation
Mechanisms mediating post-exercise cold-induced increases in PGC-1α gene expression in human skeletal muscle are yet to be fully elucidated, but may involve local cooling effects on AMPK and p38 MAPK related signalling and/or increased systemic β-adrenergic stimulation. We aimed to therefore examine whether post-exercise cold-water immersion enhancement of PGC-1α mRNA is mediated through local or systemic mechanisms. Ten subjects completed acute cycling (8x5 min at ~80% peak power output) followed by seated-rest (CON) or single-leg cold-water immersion (CWI; 10 min, 8°C). Muscle biopsies were obtained pre-, post- and 3 h post-exercise from a single limb in the CON condition but from both limbs in CWI (thereby providing tissue from a CWI and non-immersed limb, NOT). Muscle temperature decreased up to 2 h post-exercise following CWI (-5°C) in the immersed limb, with lesser changes observed in CON and NOT (-3°C; P<0.05). No differences between limbs were observed in p38MAPK phosphorylation at any time point (P<0.05), whilst a significant interaction effect was present for AMPK phosphorylation (P=0.031). Exercise (CON) increased gene expression of PGC-1α 3 h post-exercise (~5-fold; P<0.001). CWI augmented PGC-1α expression above CON in both the immersed (CWI; ~9-fold; P=0.003) and NOT limbs (~12-fold; P=0.001). Plasma Normetanephrine concentration was higher in CWI vs. CON immediately post-immersion (860 vs. 665 pmol/L; P=0.034). We report for the first time that local cooling of the immersed limb evokes transcriptional control of PGC1-α in the non-immersed limb, suggesting increased systemic β-adrenergic activation of AMPK mediates, in part, post-exercise cold-induction of PGC-1α mRNA
Direct Imaging in Reflected Light: Characterization of Older, Temperate Exoplanets With 30-m Telescopes
Direct detection, also known as direct imaging, is a method for discovering
and characterizing the atmospheres of planets at intermediate and wide
separations. It is the only means of obtaining spectra of non-transiting
exoplanets. Characterizing the atmospheres of planets in the <5 AU regime,
where RV surveys have revealed an abundance of other worlds, requires a
30-m-class aperture in combination with an advanced adaptive optics system,
coronagraph, and suite of spectrometers and imagers - this concept underlies
planned instruments for both TMT (the Planetary Systems Imager, or PSI) and the
GMT (GMagAO-X). These instruments could provide astrometry, photometry, and
spectroscopy of an unprecedented sample of rocky planets, ice giants, and gas
giants. For the first time habitable zone exoplanets will become accessible to
direct imaging, and these instruments have the potential to detect and
characterize the innermost regions of nearby M-dwarf planetary systems in
reflected light. High-resolution spectroscopy will not only illuminate the
physics and chemistry of exo-atmospheres, but may also probe rocky, temperate
worlds for signs of life in the form of atmospheric biomarkers (combinations of
water, oxygen and other molecular species). By completing the census of
non-transiting worlds at a range of separations from their host stars, these
instruments will provide the final pieces to the puzzle of planetary
demographics. This whitepaper explores the science goals of direct imaging on
30-m telescopes and the technology development needed to achieve them.Comment: (March 2018) Submitted to the Exoplanet Science Strategy committee of
the NA
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