1,405 research outputs found
Cosmological constraints on the generalized holographic dark energy
We use the Markov ChainMonte Carlo method to investigate global constraints
on the generalized holographic (GH) dark energy with flat and non-flat universe
from the current observed data: the Union2 dataset of type supernovae Ia
(SNIa), high-redshift Gamma-Ray Bursts (GRBs), the observational Hubble data
(OHD), the cluster X-ray gas mass fraction, the baryon acoustic oscillation
(BAO), and the cosmic microwave background (CMB) data. The most stringent
constraints on the GH model parameter are obtained. In addition, it is found
that the equation of state for this generalized holographic dark energy can
cross over the phantom boundary wde =-1.Comment: 14 pages, 5 figures. arXiv admin note: significant text overlap with
arXiv:1105.186
A survey on surgeons' perceived quality of the informed consent process in a Swiss paediatric surgery unit.
AIM: To evaluate the levels of satisfaction and opinions on the usefulness of the informed consent form currently in use in our Paediatric Surgery Department.
Qualitative study carried out via interviews of senior paediatric surgeons, based on a questionnaire built up from reference criteria in the literature and public health law.
RESULTS: Physicians with between 2 and 35 years experience of paediatric surgery, with a participation rate of 92 %, agreed on the definition of an informed consent form, were satisfied with the form in use and did not wish to modify its structure. The study revealed that signing the form was viewed as mandatory, but meant different things to different participants, who diverged over whom that signature protected. Finally, all respondents were in agreement over what information was necessary for parents of children requiring surgery.
CONCLUSION: Paediatric surgeons seemed to be satisfied with the informed consent form in use. Most of them did not identify that the first aim of the informed consent form is to give the patient adequate information to allow him to base his consent, which is a legal obligation, the protection of physicians by the formalisation and proof of the informed consent being secondary. Few surgeons brought up the fact that the foremost stakeholder in paediatric surgery are the children themselves and that their opinions are not always sought. In the future, moving from informed consent process to shared decision-making, a more active bidirectional exchange may be strongly considered. Involving children in such vital decisions should become the norm while keeping in mind their level of maturity
Latent Class Analysis of Gambling Activities in a Sample of Young Swiss Men: Association with Gambling Problems, Substance Use Outcomes, Personality Traits and Coping Strategies.
The study aimed to identify different patterns of gambling activities (PGAs) and to investigate how PGAs differed in gambling problems, substance use outcomes, personality traits and coping strategies. A representative sample of 4989 young Swiss males completed a questionnaire assessing seven distinct gambling activities, gambling problems, substance use outcomes, personality traits and coping strategies. PGAs were identified using latent class analysis (LCA). Differences between PGAs in gambling and substance use outcomes, personality traits and coping strategies were tested. LCA identified six different PGAs. With regard to gambling and substance use outcomes, the three most problematic PGAs were extensive gamblers, followed by private gamblers, and electronic lottery and casino gamblers, respectively. By contrast, the three least detrimental PGAs were rare or non-gamblers, lottery only gamblers and casino gamblers. With regard to personality traits, compared with rare or non-gamblers, private and casino gamblers reported higher levels of sensation seeking. Electronic lottery and casino gamblers, private gamblers and extensive gamblers had higher levels of aggression-hostility. Extensive and casino gamblers reported higher levels of sociability, whereas casino gamblers reported lower levels of anxiety-neuroticism. Extensive gamblers used more maladaptive and less adaptive coping strategies than other groups. Results suggest that gambling is not a homogeneous activity since different types of gamblers exist according to the PGA they are engaged in. Extensive gamblers, electronic and casino gamblers and private gamblers may have the most problematic PGAs. Personality traits and coping skills may predispose individuals to PGAs associated with more or less negative outcomes
Universality in Bacterial Colonies
The emergent spatial patterns generated by growing bacterial colonies have
been the focus of intense study in physics during the last twenty years. Both
experimental and theoretical investigations have made possible a clear
qualitative picture of the different structures that such colonies can exhibit,
depending on the medium on which they are growing. However, there are
relatively few quantitative descriptions of these patterns. In this paper, we
use a mechanistically detailed simulation framework to measure the scaling
exponents associated with the advancing fronts of bacterial colonies on hard
agar substrata, aiming to discern the universality class to which the system
belongs. We show that the universal behavior exhibited by the colonies can be
much richer than previously reported, and we propose the possibility of up to
four different sub-phases within the medium-to-high nutrient concentration
regime. We hypothesize that the quenched disorder that characterizes one of
these sub-phases is an emergent property of the growth and division of bacteria
competing for limited space and nutrients.Comment: 12 pages, 5 figure
New heuristic for the dynamic layout problem
The dynamic layout problem addresses the situation where the traffic among the various units within a facility changes over time. Its objective is to determine a layout for each period in a planning horizon such that the total of the flow and the relocation costs is minimized. The problem is computationally very hard and has begun to receive attention only recently. In this paper, we present a new heuristic scheme, based on the idea of viable layouts, which is easy to operationalize. A limited computational study shows that, depending upon how it is implemented, this scheme can be reasonably fast and can yield results that are competitive with those from other available solution methods
Quasiparticle spectrum of d-wave superconductors in the mixed state: a large Fermi-velocity anisotropy study
The quasiparticle spectrum of a two-dimensional d-wave superconductor in the
mixed state, H_c1 << H << H_c2, is studied for large values of the ``anisotropy
ratio'' alpha_D = v_F/v_Delta. For a square vortex lattice rotated by 45
degrees from the quasiparticle anisotropy axes (and the usual choice of
Franz--Tesanovic singular gauge transformation) we determine essential features
of the band structure asymptotically for large alpha_D, using an effective
one-dimensional model, and compare them to numerical calculations. We find that
several features of the band structure decay to zero exponentially fast for
large alpha_D. Using a different choice of singular gauge transformation, we
obtain a different band structure, but still find qualitative agreement between
the 1D and full 2D calculations. Finally, we distort the square lattice into a
non-Bravais lattice. Both the one- and two-dimensional numerical calculations
of the energy spectra show a gap around zero-energy, with our gauge choice, and
the two excitation spectra agree reasonably well.Comment: 14 pages, 13 figures, revte
LIME : Software for 3-D visualization, interpretation, and communication of virtual geoscience models
Parts of LIME have been developed to address research requirements in projects funded by the Research Council of Norway (RCN) through the Petromaks and Petromaks 2 programs. The following grants are acknowledged: 153264 (VOG [Virtual Outcrop Geology]; with Statoil ASA), 163316 (Carbonate Reservoir Geomodels [IRIS (International Research Institute of Stavanger)]), 176132 (Paleokarst Reservoirs [Uni Research CIPR]), 193059 (EUSA; with FORCE Sedimentology and Stratigraphy Group), 234152 (Trias North [University of Oslo]; with Deutsche Erdoel AG, Edison, Lundin, Statoil, and Tullow), 234111 (VOM2MPS [Uni Research CIPR]; with FORCE Sedimentology and Stratigraphy Group), as well as SkatteFUNN (RCN) project 266740. In addition, the SAFARI project consortium (http://safaridb.com) is thanked for its continued support. The OSG and wxWidgets communities are acknowledged for ongoing commitment to providing mature and powerful software libraries. All authors thank colleagues past and present for studies culminating in the presented figures: Kristine Smaadal and Aleksandra Sima (Figs. 1 and 4); Colm Pierce (Fig. 2A); Eivind Bastesen, Roy Gabrielsen and Haakon Fossen (Fig. 3); Christian Haug Eide (Fig. 7); Ivar Grunnaleite and Gunnar Sælen (Fig. 8); and Magda Chmielewska (Fig. 9). Isabelle Lecomte contributed to discussions on geospatial-geophysical data fusion. Bowei Tong and Joris Vanbiervliet are acknowledged for internal discussions during article revision. The lead author thanks Uni Research for providing a base funding grant to refine some of the presented features. Finally, authors Buckley and Dewez are grateful to Institut Carnot BRGM for the RADIOGEOM mobility grant supporting the writing of this paper. Corbin Kling and one anonymous reviewer helped improve the final manuscript.Peer reviewedPublisher PD
Does accelerating universe indicates Brans-Dicke theory
The evolution of universe in Brans-Dicke (BD) theory is discussed in this
paper.
Considering a parameterized scenario for BD scalar field
which plays the role of gravitational "constant" ,
we apply the Markov Chain Monte Carlo method to investigate a global
constraints on BD theory with a self-interacting potential according to the
current observational data: Union2 dataset of type supernovae Ia (SNIa),
high-redshift Gamma-Ray Bursts (GRBs) data, observational Hubble data (OHD),
the cluster X-ray gas mass fraction, the baryon acoustic oscillation (BAO), and
the cosmic microwave background (CMB) data. It is shown that an expanded
universe from deceleration to acceleration is given in this theory, and the
constraint results of dimensionless matter density and parameter
are, and
which is consistent with the
result of current experiment exploration, . In
addition, we use the geometrical diagnostic method, jerk parameter , to
distinguish the BD theory and cosmological constant model in Einstein's theory
of general relativity.Comment: 16 pages, 3 figure
Individual and national financial impacts of informal caring for people with mental illness in Australia, projected to 2030
Background Mental illness has a significant impact not only on patients, but also on their carers\u27 capacity to work. Aims To estimate the costs associated with lost labour force participation due to the provision of informal care for people with mental illness in Australia, such as income loss for carers and lost tax revenue and increased welfare payments for government, from 2015 to 2030. Method The output data of a microsimulation model Care&WorkMOD were analysed to project the financial costs of informal care for people with mental illness, from 2015 to 2030. Care&WorkMOD is a population-representative microsimulation model of the Australian population aged between 15 and 64 years, built using the Australian Bureau of Statistics Surveys of Disability, Ageing and Carers data and the data from other population-representative microsimulation models. Results The total annual national loss of income for all carers due to caring for someone with mental illness was projected to rise from AU645 million (£314 million) in 2030 in real terms. For the government, the total annual lost tax revenue was projected to rise from AU170 million (£82.8 million) in 2030 and welfare payments to increase from AU220 million (£107 million) in 2030. Conclusions The costs associated with lost labour force participation due to the provision of informal care for people with mental illness are projected to increase for both carers and government, with a widening income gap between informal carers and employed non-carers, putting carers at risk of increased inequality
Field Theoretical Quantum Effects on the Kerr Geometry
We study quantum aspects of the Einstein gravity with one time-like and one
space-like Killing vector commuting with each other. The theory is formulated
as a \coset nonlinear -model coupled to gravity. The quantum analysis
of the nonlinear -model part, which includes all the dynamical degrees
of freedom, can be carried out in a parallel way to ordinary nonlinear
-models in spite of the existence of an unusual coupling. This means
that we can investigate consistently the quantum properties of the Einstein
gravity, though we are limited to the fluctuations depending only on two
coordinates. We find the forms of the beta functions to all orders up to
numerical coefficients. Finally we consider the quantum effects of the
renormalization on the Kerr black hole as an example. It turns out that the
asymptotically flat region remains intact and stable, while, in a certain
approximation, it is shown that the inner geometry changes considerably however
small the quantum effects may be.Comment: 16 pages, LaTeX. The hep-th number added on the cover, and minor
typos correcte
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