542 research outputs found
New hyper-Kaehler manifolds by fixing monopoles
The construction of new hyper-Kaehler manifolds by taking the infinite
monopole mass limit of certain Bogomol'nyi-Prasad-Sommerfield monopole moduli
spaces is considered. The one-parameter family of hyperkaehler manifolds due to
Dancer is shown to be an example of such manifolds. A new family of fixed
monopole spaces is constructed. They are the moduli spaces of four SU(4)
monopoles, in the infinite mass limit of two of the monopoles. These manifolds
are shown to be nonsingular when the fixed monopole positions are distinct.Comment: Version in Phys. Rev. D. 11 pp, RevTeX, 14 Postscript diagram
Universal Baxterization for -graded Hopf algebras
We present a method for Baxterizing solutions of the constant Yang-Baxter
equation associated with -graded Hopf algebras. To demonstrate the
approach, we provide examples for the Taft algebras and the quantum group
.Comment: 8 page
Risk of Organism Acquisition From Prior Room Occupants: A Systematic Review and Meta-Analysis
A systematic review and meta-analysis was conducted to determine the risk of pathogen acquisition for patients associated with prior room occupancy. The analysis was also broadened to examine any differences in acquisition risk between Gram-positive and Gram–negative organisms
Controlling Methicillin-Resistant Staphylococcus Aureus (MRSA) in a Hospital and the Role of Hydrogen Peroxide Decontamination: An Interrupted Time Series Analysis
Objectives The impact of surface disinfection versus detergent cleaning on healthcare associated infection rates remains unresolved. We aimed to evaluate the efficacy of hydrogen peroxide (HP) decontamination against methicillin-resistant Staphylococcus aureus (MRSA). Design Single centred retrospective before and after study design. Setting Launceston General Hospital, Tasmania, Australia. Participants Patients with MRSA infection or colonisation. Interventions Rooms occupied by patients with MRSA infection or colonisation were cleaned following discharge with either detergent or HP. Main outcome measures MRSA room contamination following cleaning; new MRSA acquisition in patients.
ResultsOver 3600 discharge cleans were completed, with more than 32 600 environmental swabs processed. MRSA was isolated from 24.7% rooms following detergent cleaning and from 18.8% of rooms after HP (p Conclusions Use of HP disinfection led to a decrease in residual MRSA contamination in patient rooms compared with detergent. It may also have encouraged the reduction in patient MRSA acquisition despite several confounders including staff feedback on terminal cleaning, additional MRSA screening and quicker laboratory methods. Infection control is best served by concurrent interventions targeting both the patient and healthcare environment
What\u27s Trending in Infection Control? Scoping and Narrative Reviews
Objective.
To explore the trends in infection control peer-reviewed journals, mainstream media, and blogs written by infection control professionals
Design.
Narrative and scoping reviews methods. Narrative and scoping reviews were performed to identify trending infection prevention and control topics from international journals, national news websites, newspapers, and so-called grey literature throughout 2015. Data were analysed using word frequencies and results are displayed in word clouds.
Results.
For 2015, our search identified 6 news websites with a total of published 116 articles, 71 articles from selected newspapers, and 214 publications from infection control websites. In total, 1,059 journal articles were initially identified; 98 articles were anonymous and thus were excluded, leaving 961 articles in the reviews. The terms ‘superbug’ and ‘antibiotics’ were most commonly used in titles of news websites and newspapers, whereas the terms ‘infection’ and ‘prevention’ were most commonly used in infection control websites or blogs.
The word frequency differences among the 4 selected journals reflected their respective specialties.
Conclusion.
In infection prevention and control, the integration of a range of mediums is necessary to best serve public interests. Whether the aim is advocacy, general health information dissemination, or warnings of imminent risk, health researchers have access to multiple forums with different strengths through which to influence public risk perceptions and responses
On the structure of the set of bifurcation points of periodic solutions for multiparameter Hamiltonian systems
This paper deals with periodic solutions of the Hamilton equation with many
parameters. Theorems on global bifurcation of solutions with periods
from a stationary point are proved. The Hessian matrix of the
Hamiltonian at the stationary point can be singular. However, it is assumed
that the local topological degree of the gradient of the Hamiltonian at the
stationary point is nonzero. It is shown that (global) bifurcation points of
solutions with given periods can be identified with zeros of appropriate
continuous functions on the space of parameters. Explicit formulae for such
functions are given in the case when the Hessian matrix of the Hamiltonian at
the stationary point is block-diagonal. Symmetry breaking results concerning
bifurcation of solutions with different minimal periods are obtained. A
geometric description of the set of bifurcation points is given. Examples of
constructive application of the theorems proved to analytical and numerical
investigation and visualization of the set of all bifurcation points in given
domain are provided.
This paper is based on a part of the author's thesis [W. Radzki, ``Branching
points of periodic solutions of autonomous Hamiltonian systems'' (Polish), PhD
thesis, Nicolaus Copernicus University, Faculty of Mathematics and Computer
Science, Toru\'{n}, 2005].Comment: 35 pages, 4 figures, PDFLaTe
Some remarks on the isoperimetric problem for the higher eigenvalues of the Robin and Wentzell Laplacians
We consider the problem of minimising the th eigenvalue, , of
the (-)Laplacian with Robin boundary conditions with respect to all domains
in of given volume . When , we prove that the second
eigenvalue of the -Laplacian is minimised by the domain consisting of the
disjoint union of two balls of equal volume, and that this is the unique domain
with this property. For and , we prove that in many cases a
minimiser cannot be independent of the value of the constant in the
boundary condition, or equivalently of the volume . We obtain similar
results for the Laplacian with generalised Wentzell boundary conditions .Comment: 16 page
Weyl Equation and (Non)-Commutative SU(n+1) BPS Monopoles
We apply the ADHMN construction to obtain the SU(n+1)(for generic values of
n) spherically symmetric BPS monopoles with minimal symmetry breaking. In
particular, the problem simplifies by solving the Weyl equation, leading to a
set of coupled equations, whose solutions are expressed in terms of the
Whittaker functions. Next, this construction is generalized for non-commutative
SU(n+1) BPS monopoles, where the corresponding solutions are given in terms of
the Heun B functions.Comment: 16 pages, Latex. Few typos corrected, version to appear in JHE
Einstein-Weyl structures corresponding to diagonal K\"ahler Bianchi IX metrics
We analyse in a systematic way the four dimensionnal Einstein-Weyl spaces
equipped with a diagonal K\"ahler Bianchi IX metric. In particular, we show
that the subclass of Einstein-Weyl structures with a constant conformal scalar
curvature is the one with a conformally scalar flat - but not necessarily
scalar flat - metric ; we exhibit its 3-parameter distance and Weyl one-form.
This extends previous analysis of Pedersen, Swann and Madsen , limited to the
scalar flat, antiself-dual case. We also check that, in agreement with a
theorem of Derdzinski, the most general conformally Einstein metric in the
family of biaxial K\"ahler Bianchi IX metrics is an extremal metric of Calabi,
conformal to Carter's metric, thanks to Chave and Valent's results.Comment: 15 pages, Latex file, minor modifications, to be published in Class.
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