853 research outputs found
Inzicht in de gemeentelijke prioriteit:een onderzoek naar de verbetering van de processnelheid van Ruimte voor Ruimte projecten
Phase diagram of Regge quantum gravity coupled to SU(2) gauge theory
We analyze Regge quantum gravity coupled to SU(2) gauge theory on , and simplicial lattices. It turns out that
the window of the well-defined phase of the gravity sector where geometrical
expectation values are stable extends to negative gravitational couplings as
well as to gauge couplings across the deconfinement phase transition. We study
the string tension from Polyakov loops, compare with the -function of
pure gauge theory and conclude that a physical limit through scaling is
possible.Comment: RevTeX, 14 pages, 5 figures (2 eps, 3 tex), 2 table
Nuclear Spin Relaxation for Higher Spin
We study the relaxation of a spin I that is weakly coupled to a quantum
mechanical environment. Starting from the microscopic description, we derive a
system of coupled relaxation equations within the adiabatic approximation.
These are valid for arbitrary I and also for a general stationary
non--equilibrium state of the environment. In the case of equilibrium, the
stationary solution of the equations becomes the correct Boltzmannian
equilibrium distribution for given spin I. The relaxation towards the
stationary solution is characterized by a set of relaxation times, the longest
of which can be shorter, by a factor of up to 2I, than the relaxation time in
the corresponding Bloch equations calculated in the standard perturbative way.Comment: 4 pages, Latex, 2 figure
Fluid structure interaction analysis: vortex shedding induced vibrations
Abstract Fluid Structure Interaction (FSI) numerical modelling requires an efficient workflow to properly capture the physics involved. Computational Structural Mechanics (CSM) and Computation Fluid Dynamics (CFD) have to be coupled and at the moment there is a lack of monolithic solvers capable to tackle industrial applications that involves high fidelity models which mesh can be comprised of hundred millions of cells. This paper shows an efficient approach based on standard commercial tools. The FEM solver ANSYS® Mechanical™ is used to extract a given number of eigenmodes. Then the modal shapes are imported in the CFD solver Fluent® using the Add On RBF Morph™. Updating the modal coordinates it is possible to adapt the shape of the model by taking into account the elasticity of the CFD model. Transient analysis is faced using a time marching solution by updating the shape of the mesh at each time step (weak coupling, evaluated as single DOF systems and integrating modal forces over the CFD grid). Numerical performances and solution accuracy of this approach are analyzed on a practical application (NACA0009 Hydrofoil) for which experimental data are available. A comparison between proposed method and experiment is provided. Transient coupled solver is used for the computation of eigenvalues in water by post processing the free vibration response in calm fluid
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Associations between job demands, job resources and patient-related burnout among physicians: results from a multicentre observational study
Objectives To investigate associations of job demands
and resources with patient-related burnout among
physicians.
Design Multicentre observational study.
Setting Fifty medical departments at 14 (academic and
non-academic) hospitals in the Netherlands.
Participants Four hundred sixty-five physicians
(71.6% response rate), comprising 385 (82.8%) medical
specialists and 80 (17.2%) residents.
Main outcome measures Job demands (workload and
bureaucratic demands), job resources (participation in
decision making, development opportunities, leader’s
inspiration, relationships with colleagues and patients)—
measured with the validated Questionnaire of Experience
and Evaluation of Work and Physician Worklife Survey—
and patient-related burnout, measured using the validated
Copenhagen Burnout Inventory.
Results Patient-related burnout was positively associated
with workload (b=0.36; 95% CI, 0.25 to 0.48; p<0.001)
and negatively associated with development opportunities
(b=–0.18; 95% CI, –0.27 to –0.08; p<0.001) and
relationships with patients (b=–0.12; 95% CI, –0.22 to
–0.03; p=0.01). Relationships with patients moderated
the association between bureaucratic demands and
patient-related burnout (b=–0.15; 95% CI, –0.27 to –0.04;
p=0.01).
Conclusions Physicians with high workloads and few
development opportunities reported higher levels of
patient-related burnout. Those with positive patient
relationships were less likely to experience patient-related
burnout, even in the presence of excessive bureaucracy.
Therefore, positive physician–patient relationships may be
supported to reduce the likelihood of physicians’ patientrelated burnout. Howeve
QT Variability and Other Electrocardiographic Predictors of Sudden Cardiac Death
This thesis investigates sudden cardiac death, focusing of QT variability, heart-rate variability and other electrocardiographic markers. Topics include:
- Normal values for heart-rate variability
- Normal values for QT variability
- The association of QT variability with sudden cardiac death
- The association of QT variability with Heart Failure
- The association of thyroid function and Sudden cardiac death
- The association of thyroid function with QT variability
- The association of COPD with sudden cardiac deat
Pharmacogenetics of Drug-Induced QT Interval Prolongation: An Update
A prolonged QT interval is an important risk factor for ventricular arrhythmias and sudden cardiac death. QT prolongation can be caused by drugs. There are multiple risk factors for drug-induced QT prolongation, including genetic variation. QT prolongation is one of the most common reasons for withdrawal of
Inactive and sedentary lifestyles amongst ambulatory adolescents and young adults with cerebral palsy
Background: To assess physical behaviour, including physical activity and sedentary behaviour, of ambulatory adolescents and young adults with cerebral palsy (CP). We compared participant physical behaviour to that of able-bodied persons and assessed differences related to Gross Motor Functioning Classification System (GMFCS) level and CP distribution (unilateral/bilateral). Methods. In 48 ambulatory persons aged 16 to 24 years with spastic CP and in 32 able-bodied controls, physical behaviour was objectively determined with an accelerometer-based activity monitor. Total duration, intensity and type of physical activity were assessed and sedentary time was determined (lying and sitting). Furthermore, distribution of walking bouts and sitting bouts was specified. Results: Adolescents and young adults with CP spent 8.6% of 24 hours physically active and 79.5% sedentary, corresponding with respectively 123 minutes and 1147 minutes per 24 hours. Compared to able-bodie
Properties of Interfaces in the two and three dimensional Ising Model
To investigate order-order interfaces, we perform multimagnetical Monte Carlo
simulations of the and Ising model. Following Binder we extract the
interfacial free energy from the infinite volume limit of the magnetic
probability density. Stringent tests of the numerical methods are performed by
reproducing with high precision exact results. In the physically more
interesting case we estimate the amplitude of the critical
interfacial tension to be . This
result is in good agreement with a previous MC calculation by Mon, as well as
with experimental results for related amplitude ratios. In addition, we study
in some details the shape of the magnetic probability density for temperatures
below the Curie point.Comment: 25 pages; sorry no figures include
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