2,076 research outputs found
A note on the effect of post-mortem maturation on colour of bovine Longissimus dorsi muscle
peer-reviewedFinancial support to P.G. Dunne was provided
under the Walsh Fellowship programme of Teagasc.Fifteen heifers were housed and fed a concentrate diet while 54 counterparts grazed
at pasture for 90 days at which stage six heifers from each group were slaughtered.
The remaining animals in the pasture group were then housed and offered either:
concentrate only; concentrate plus grass silage with silage accounting for either 20%
or 50% of the total dry matter offered; or zero-grazed grass plus concentrate with
grass accounting for 83% of the dry matter offered. Heifers (3/diet) were slaughtered
28, 56, 91 and 120 days thereafter. Colour characteristics of M. longissimus dorsi (LD)
were measured at 48 h post mortem. The LD was then vacuum-packaged and stored
at between 0 and 4 °C in darkness for 12 days, when colour characteristics were
again measured. Maturation of LD resulted in meat that had higher redness values
(‘a’ value; P<0.001) and a more intense red colour (higher ‘C’ value; P<0.001) at 14
days post mortem than at 2 days, regardless of diet/duration of feeding. Maturation
also resulted in a brighter colour (higher ‘L’ value; P<0.001) but this difference was
greatest when cattle were slaughtered the day-56 time point
Roads and traffic authority of new south Wales v dederer: Negligence and the exuberance of youth
This case note examines the decision of the High Court of Australia in Roads and Traffic Authority of New South Wales v Dederer, which marks the common law's continued departure from shared liability for tragic accidents into the realm of personal liability. The decision has particular significance for children and young people who may be held accountable for their reckless actions, notwithstanding the 'exuberance of youth'. In particular, the case note analyses the High Court's emphasis on obvious risks and personal responsibility and the Court's attempt to limit liability through a consideration of the plaintiff's conduct on questions of the scope of the duty of care and at the breach of duty enquiry, rather than confining it to the issue of the plaintiff's contributory negligence
form factors from lattice QCD
We report the first lattice QCD calculation of the form factors for the
standard model tree-level decay . In combination with future
measurement, this calculation will provide an alternative exclusive
semileptonic determination of . We compare our results with previous
model calculations, make predictions for differential decay rates and branching
fractions, and predict the ratio of differential branching fractions between
and . We also present standard model
predictions for differential decay rate forward-backward asymmetries,
polarization fractions, and calculate potentially useful ratios of
form factors with those of the fictitious decay. Our lattice
simulations utilize NRQCD and HISQ light quarks on a subset of the MILC
Collaboration's asqtad gauge configurations, including two lattice
spacings and a range of light quark masses.Comment: 24 pages, 21 figures; Ver. 2 matches published versio
B→Dlν form factors at nonzero recoil and extraction of |Vcb|
We present a lattice QCD calculation of the B→Dlν semileptonic decay form factors f+(q2) and f0(q2) for the entire physical q2 range. Nonrelativistic QCD bottom quarks and highly improved staggered quark charm and light quarks are employed together with Nf=2+1 MILC gauge configurations. A joint fit to our lattice and BABAR experimental data allows an extraction of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb|. We also determine the phenomenologically interesting ratio R(D)=B(B→Dτντ)/B(B→Dlνl) (l=e,μ). We find |Vcb|B→Dexcl=0.0402(17)(13), where the first error consists of the lattice simulation errors and the experimental statistical error and the second error is the experimental systematic error. For the branching fraction ratio we find R(D)=0.300(8)
Transport in time-dependent dynamical systems: Finite-time coherent sets
We study the transport properties of nonautonomous chaotic dynamical systems
over a finite time duration. We are particularly interested in those regions
that remain coherent and relatively non-dispersive over finite periods of time,
despite the chaotic nature of the system. We develop a novel probabilistic
methodology based upon transfer operators that automatically detects maximally
coherent sets. The approach is very simple to implement, requiring only
singular vector computations of a matrix of transitions induced by the
dynamics. We illustrate our new methodology on an idealized stratospheric flow
and in two and three dimensional analyses of European Centre for Medium Range
Weather Forecasting (ECMWF) reanalysis data
Improving the theoretical prediction for the width difference: matrix elements of next-to-leading order operators
We present lattice QCD results for the matrix elements of and other
dimension-7, operators relevant for calculations of , the width difference. We have computed correlation
functions using 5 ensembles of the MILC Collaboration's 2+1+1-flavour gauge
field configurations, spanning 3 lattice spacings and light sea quarks masses
down to the physical point. The HISQ action is used for the valence strange
quarks, and the NRQCD action is used for the bottom quarks. Once our analysis
is complete, the theoretical uncertainty in the Standard Model prediction for
will be substantially reduced.Comment: 8 pages. To appear in the Proceedings of the 35th International
Symposium on Lattice Field Theory, 18-24 June 2017, Granada, Spai
B and Bs semileptonic decay form factors with NRQCD/HISQ quarks
We discuss our ongoing effort to calculate form factors for several B and Bs
semileptonic decays. We have recently completed the first unquenched
calculation of the form factors for the rare decay B -> K ll. Extrapolated over
the full kinematic range of q^2 via model-independent z expansion, these form
factor results allow us to calculate several Standard Model observables. We
compare with experiment (Belle, BABAR, CDF, and LHCb) where possible and make
predictions elsewhere. We discuss preliminary results for Bs -> K l nu which,
when combined with anticipated experimental results, will provide an
alternative exclusive determination of |Vub|. We are exploring the possibility
of using ratios of form factors for this decay with those for the unphysical
decay Bs -> eta_s as a means of significantly reducing form factor errors. We
are also studying B -> pi l nu, form factors for which are combined with
experiment in the standard exclusive determination of |Vub|. Our simulations
use NRQCD heavy and HISQ light valence quarks on the MILC 2+1 dynamical asqtad
configurations.Comment: 7 pages, 5 figures, presented at the 31st International Symposium on
Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, German
Form Factors and the Fragmentation Fraction Ratio
We present a lattice quantum chromodynamics determination of the scalar and
vector form factors for the decay over the full
physical range of momentum transfer. In conjunction with future experimental
data, our results will provide a new method to extract , which may
elucidate the current tension between exclusive and inclusive determinations of
this parameter. Combining the form factor results at non-zero recoil with
recent HPQCD results for the form factors, we
determine the ratios and . These results give the fragmentation
fraction ratios and ,
respectively. The fragmentation fraction ratio is an important ingredient in
experimental determinations of meson branching fractions at hadron
colliders, in particular for the rare decay . In addition to the form factor results, we make the first prediction
of the branching fraction ratio , where is an electron or muon. Current
experimental measurements of the corresponding ratio for the semileptonic
decays of mesons disagree with Standard Model expectations at the level of
nearly four standard deviations. Future experimental measurements of
may help understand this discrepancy.Comment: 21 pages, 15 figure
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