320 research outputs found
Has incentive payment improved venous thrombo-embolism risk assessment and treatment of hospital in-patients?
This paper focuses on financial incentives rewarding successful implementation of guidelines in the UK National Health Service (NHS). In particular, it assesses the implementation of National Institute for Health and Clinical Excellence (NICE) venous thrombo-embolism (VTE) guidance in 2010 on the risk assessment and secondary prevention of VTE in hospital in-patients and the financial incentives driving successful implementation introduced by the Commissioning for Quality and Innovation for Payment Framework (CQUIN) for 2010-2011. We systematically compared the implementation of evidence-based national guidance on VTE prevention across two specialities (general medicine and orthopaedics) in four hospital sites in the greater South West of England by auditing and evaluating VTE prevention activity for 2009 (i.e. before the 2010 NICE guideline) and late 2010 (almost a year after the guideline was published). Analysis of VTE prevention activity reported in 816 randomly selected orthopaedic and general medical in-patient medical records was complemented by a qualitative study into the practical responses to revised national guidance. This paper's contribution to knowledge is to suggest that by financially rewarding the implementation of national guidance on VTE prevention, paradoxes and contradictions have become apparent between the 'payment by volume system' of Healthcare Resource Groups and the 'payment by results' system of CQUIN
Surface and structural properties of Pt/CeO2 catalyst under preferential CO oxidation in hydrogen (PROX)
Preferential oxidation of CO in the presence of excess hydrogen was studied on Pt/CeO2 with 5% metal loading. Catalytic data were similar to those observed on 1% Pt/CeO2 earlier [Wootsch et al. J. Catal. 225 (2004) 259]. The optimum temperature region is T373 K; conversion and selectivity of CO oxidation strongly decreased at higher temperatures. High-pressure XPS indicated CO adsorbed on platinum particles and significant amount of water on the ceria surface. The top-most ceria surface re-oxidized as small amount of oxygen (3%) was introduced into the H2/CO feed. Despite this surface re-oxidation, high-resolution TEM after reaction indicated oxygen deficient ceria bulk structure, in which the defects formed a super-cell, with CeO1.695 structure. The defective ceria is suggested to play an important role stabilizing the hydrogen bonded surface water, which (i) suppresses further hydrogen oxidation and (ii) reacts at the metal/support interface with linearly adsorbed CO in a low temperature water-gas-shift type reaction to produce CO2
Маркшейдерська школа Національного гірничого університету
Викладена історія створення та розвитку маркшейдерської школи в НГУ протягом 110 років.Изложена история создания и развития маркшейдерской школы в НГУ в течение 110 лет.History of creation and development ofsurveyor school is expounded in NMU during 110 years
Preferential CO oxidation in hydrogen (PROX) on ceria-supported catalysts PART II. Oxidation states and surface species on Pd/CeO2 under reaction conditions, suggested reaction mechanism
The aim of the PROX reaction is to reduce the CO content of hydrogen feed to proton-exchange membrane fuel cells (PEMFCs) by selective oxidation of CO in the presence of excess hydrogen. Both Pt and Pd on ceria are active in CO oxidation (without hydrogen), whereas Pd is poorly active in the presence of hydrogen. In this paper we explore the reasons for such behavior, using the same techniques for Pd/CeO2 as used for Pt/CeO2 in Part I: catalytic tests, in situ DRIFTS, high-pressure XPS, HRTEM, and TDS. We also examine the reaction mechanism of CO oxidation (without hydrogen), which does not occur via exactly the same mechanism on Pt and Pd/CeO2 catalysts. In the presence of hydrogen (PROX) at low temperature (T = 350–380 K), the formation of Pd β-hydride was confirmed by high-pressure in situ XPS. Its formation greatly suppressed the possibility of CO oxidation, because oxygen both from gas-phase and support sites reacted rapidly with hydride H to form water, which readily desorbed from Pd. Nevertheless, CO adsorption was not hampered here. These entities transformed mainly to surface formate and formyl (–CHO) species instead of oxidation as observed by DRIFTS. The participation of a low-temperature water–gas shift type reaction proposed for the platinum system (see Part I) was hindered. Increasing temperature led to decomposition of the hydride phase and a parallel increase in the selectivity toward CO oxidation. This still remained lower on Pd/CeO2 than on Pt/CeO2, however
Cooling toolbox for atoms in optical lattices
We propose and analyze several schemes for cooling bosonic and fermionic
atoms in an optical lattice potential close to the ground state of the
no-tunnelling regime. Some of the protocols rely on the concept of algorithmic
cooling, which combines occupation number filtering with ideas from ensemble
quantum computation. We also design algorithms that create an ensemble of
defect-free quantum registers. We study the efficiency of our protocols for
realistic temperatures and in the presence of a harmonic confinement. We also
propose an incoherent physical implementation of filtering which can be
operated in a continuous way.Comment: 14 pages, 13 figure
Neutron time-of-flight measurements of charged-particle energy loss in inertial confinement fusion plasmas
Neutron spectra from secondary ^{3}H(d,n)α reactions produced by an implosion of a deuterium-gas capsule at the National Ignition Facility have been measured with order-of-magnitude improvements in statistics and resolution over past experiments. These new data and their sensitivity to the energy loss of fast tritons emitted from thermal ^{2}H(d,p)^{3}H reactions enable the first statistically significant investigation of charged-particle stopping via the emitted neutron spectrum. Radiation-hydrodynamic simulations, constrained to match a number of observables from the implosion, were used to predict the neutron spectra while employing two different energy loss models. This analysis represents the first test of stopping models under inertial confinement fusion conditions, covering plasma temperatures of k_{B}T≈1-4 keV and particle densities of n≈(12-2)×10^{24} cm^{-3}. Under these conditions, we find significant deviations of our data from a theory employing classical collisions whereas the theory including quantum diffraction agrees with our data
Molecular Dynamics Simulations of Temperature Equilibration in Dense Hydrogen
The temperature equilibration rate in dense hydrogen (for both T_{i}>T_{e}
and T_i<T_e) has been calculated with molecular dynamics simulations for
temperatures between 10 and 600 eV and densities between 10^{20}/cc to
10^{24}/cc. Careful attention has been devoted to convergence of the
simulations, including the role of semiclassical potentials. We find that for
Coulomb logarithms L>1, a model by Gericke-Murillo-Schlanges (GMS) [Gericke et
al., PRE 65, 036418 (2002)] based on a T-matrix method and the approach by
Brown-Preston-Singleton [Brown et al., Phys. Rep. 410, 237 (2005)] agrees with
the simulation data to within the error bars of the simulation. For smaller
Coulomb logarithms, the GMS model is consistent with the simulation results.
Landau-Spitzer models are consistent with the simulation data for L>4
Signatures of three-nucleon interactions in few-nucleon systems
Recent experimental results in three-body systems have unambiguously shown
that calculations based only on nucleon-nucleon forces fail to accurately
describe many experimental observables and one needs to include effects which
are beyond the realm of the two-body potentials. This conclusion owes its
significance to the fact that experiments and calculations can both be
performed with a high accuracy. In this review, both theoretical and
experimental achievements of the past decade will be underlined. Selected
results will be presented. The discussion on the effects of the three-nucleon
forces is, however, limited to the hadronic sector. It will be shown that
despite the major successes in describing these seemingly simple systems, there
are still clear discrepancies between data and the state-of-the-art
calculations.Comment: accepted for publication in Rep. Prog. Phy
Quantum Computing and Quantum Simulation with Group-II Atoms
Recent experimental progress in controlling neutral group-II atoms for
optical clocks, and in the production of degenerate gases with group-II atoms
has given rise to novel opportunities to address challenges in quantum
computing and quantum simulation. In these systems, it is possible to encode
qubits in nuclear spin states, which are decoupled from the electronic state in
the S ground state and the long-lived P metastable state on the
clock transition. This leads to quantum computing scenarios where qubits are
stored in long lived nuclear spin states, while electronic states can be
accessed independently, for cooling of the atoms, as well as manipulation and
readout of the qubits. The high nuclear spin in some fermionic isotopes also
offers opportunities for the encoding of multiple qubits on a single atom, as
well as providing an opportunity for studying many-body physics in systems with
a high spin symmetry. Here we review recent experimental and theoretical
progress in these areas, and summarise the advantages and challenges for
quantum computing and quantum simulation with group-II atoms.Comment: 11 pages, 7 figures, review for special issue of "Quantum Information
Processing" on "Quantum Information with Neutral Particles
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