1,583 research outputs found
Emergence of enterovirus 71 C4a in Denmark, 2009 to 2013
Enterovirus (EV) 71 has emerged as a primary cause of severe neurologic enterovirus infection in the aftermath of the global polio eradication effort. Eleven subgenotypes of EV71 exist, the C4 subgenotype being associated with large outbreaks in Asia with high mortality rates. This subgenotype has rarely been reported in Europe. In the period between 1 January 2009 and 31 December 2013 a total of 1,447 EV positive samples from 1,143 individuals were sent to the Statens Serum Institute (SSI), and 938 samples from 913 patients were genotyped at the Danish National World Health Organization Reference laboratory for Poliovirus at SSI. Echovirus 6 (E06) (n=141 patients), echovirus 30 (E30) (n=114), coxsackievirus A6 (CA06) (n=96) and EV71 (n=63) were the most prevalent genotypes. We observed a shift in circulating EV71 subgenotypes during the study period, with subgenotype C4 dominating in 2012. A total of 34 EV71 patients were found to be infected with strains of the C4 subgenotype, and phylogenetic analysis revealed that they belonged to the C4a lineage. In our study, the proportions of cases with cerebral and/or sepsis-like symptoms were similar in those affected by C4a (19/34) and those with C1 and C2 (15/35). The majority (n=30) of the 34 EV71 C4 cases were children ≤5 years of age, and males (n=22) were over-represented. Continued EV surveillance is required to monitor the spread of EV71 C4 in Denmark and the rest of Europe.
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Next-to-leading order multi-leg processes for the Large Hadron Collider
In this talk we discuss recent progress concerning precise predictions for
the LHC. We give a status report of three applications of our method to deal
with multi-leg one-loop amplitudes: The interference term of Higgs production
by gluon- and weak boson fusion to order O(alpha^2 alpha_s^3) and the
next-to-leading order corrections to the two processes pp -> ZZ jet and u ubar
-> d dbar s sbar. The latter is a subprocess of the four jet cross section at
the LHC.Comment: 6 pages, 5 figures. Talk given at the 8th international Symposium on
Radiative Corrections (RADCOR), October 1-5 2007, Florence, Ital
Three-loop matching coefficients for hot QCD: Reduction and gauge independence
We perform an integral reduction for the 3-loop effective gauge coupling and
screening mass of QCD at high temperatures, defined as matching coefficients
appearing in the dimensionally reduced effective field theory (EQCD).
Expressing both parameters in terms of a set master (sum-) integrals, we show
explicit gauge parameter independence. The lack of suitable methods for solving
the comparatively large number of master integrals forbids the complete
evaluation at the moment. Taking one generic class of masters as an example, we
highlight the calculational techniques involved. The full result would allow to
improve on one of the classic probes for the convergence of the weak-coupling
expansion at high temperatures, namely the comparison of full and effective
theory determinations of the spatial string tension. Furthermore, the full
result would also allow to determine one new contribution of order O(g**7) to
the pressure of hot QCD.Comment: 19 pages, 2 figures. v2: new Section 6 discussing applications, to
match journal versio
Survey of the needs of patients with spinal cord injury: impact and priority for improvement in hand function in tetraplegics\ud
Objective: To investigate the impact of upper extremity deficit in subjects with tetraplegia.\ud
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Setting: The United Kingdom and The Netherlands.\ud
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Study design: Survey among the members of the Dutch and UK Spinal Cord Injury (SCI) Associations.\ud
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Main outcome parameter: Indication of expected improvement in quality of life (QOL) on a 5-point scale in relation to improvement in hand function and seven other SCI-related impairments.\ud
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Results: In all, 565 subjects with tetraplegia returned the questionnaire (overall response of 42%). Results in the Dutch and the UK group were comparable. A total of 77% of the tetraplegics expected an important or very important improvement in QOL if their hand function improved. This is comparable to their expectations with regard to improvement in bladder and bowel function. All other items were scored lower.\ud
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Conclusion: This is the first study in which the impact of upper extremity impairment has been assessed in a large sample of tetraplegic subjects and compared to other SCI-related impairments that have a major impact on the life of subjects with SCI. The present study indicates a high impact as well as a high priority for improvement in hand function in tetraplegics.\ud
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The electronic structure of the heavy fermion metal
The electronic structure of the first reported heavy fermion compound without
f-electrons LiV_2O_4 was studied by an ab-initio calculation method. In the
result of the trigonal splitting and d-d Coulomb interaction one electron of
the configuration of V ion is localized and the rest partially fills
a relatively broad conduction band. The effective Anderson impurity model was
solved by Non-Crossing-Approximation method, leading to an estimation for the
single-site Kondo energy scale T_K. Then, we show how the so-called exhaustion
phenomenon of Nozi\`eres for the Kondo lattice leads to a remarkable decrease
of the heavy-fermion (or coherence) energy scale (D
is the typical bandwidth), comparable to the experimental result.Comment: 4 pages, RevTeX; 3 figures in format .eps. submitted to PR
Golem95C: A library for one-loop integrals with complex masses
We present a program for the numerical evaluation of scalar integrals and
tensor form factors entering the calculation of one-loop amplitudes which
supports the use of complex masses in the loop integrals. The program is built
on an earlier version of the golem95 library, which performs the reduction to a
certain set of basis integrals using a formalism where inverse Gram
determinants can be avoided. It can be used to calculate one-loop amplitudes
with arbitrary masses in an algebraic approach as well as in the context of a
unitarity-inspired numerical reconstruction of the integrand.Comment: 22 pages, 3 figure
QCD-like theories at nonzero temperature and density
We investigate the properties of hot and/or dense matter in QCD-like theories
with quarks in a (pseudo)real representation of the gauge group using the
Nambu-Jona-Lasinio model. The gauge dynamics is modeled using a simple lattice
spin model with nearest-neighbor interactions. We first keep our discussion as
general as possible, and only later focus on theories with adjoint quarks of
two or three colors. Calculating the phase diagram in the plane of temperature
and quark chemical potential, it is qualitatively confirmed that the critical
temperature of the chiral phase transition is much higher than the
deconfinement transition temperature. At a chemical potential equal to half of
the diquark mass in the vacuum, a diquark Bose-Einstein condensation (BEC)
phase transition occurs. In the two-color case, a Ginzburg-Landau expansion is
used to study the tetracritical behavior around the intersection point of the
deconfinement and BEC transition lines, which are both of second order. We
obtain a compact expression for the expectation value of the Polyakov loop in
an arbitrary representation of the gauge group (for any number of colors),
which allows us to study Casimir scaling at both nonzero temperature and
chemical potential.Comment: JHEP class, 31 pages, 7 eps figures; v2: error in Eq. (3.11) fixed,
two references added; matches published versio
Stresses in silos: Comparison between theoretical models and new experiments
We present precise and reproducible mean pressure measurements at the bottom
of a cylindrical granular column. If a constant overload is added, the pressure
is linear in overload and nonmonotonic in the column height. The results are
{\em quantitatively} consistent with a local, linear relation between stress
components, as was recently proposed by some of us. They contradict the
simplest classical (Janssen) approximation, and may pose a rather severe test
of competing models.Comment: 4 pages, 2 figures, final version to appear in Phys. Rev. Let
Can We Really Prevent Suicide?
Every year, suicide is among the top 20 leading causes of death globally for all ages. Unfortunately, suicide is difficult to prevent, in large part because the prevalence of risk factors is high among the general population. In this review, clinical and psychological risk factors are examined and methods for suicide prevention are discussed. Prevention strategies found to be effective in suicide prevention
include means restriction, responsible media coverage, and general public education, as well identification methods such as screening, gatekeeper training, and primary care physician education. Although the treatment for preventing suicide is difficult, follow-up that includes pharmacotherapy, psychotherapy, or both may be useful. However, prevention methods cannot be restricted to the individual. Community, social, and policy interventions will also be essentia
Orbital state and magnetic properties of LiV_2 O_4
LiV_2 O_4 is one of the most puzzling compounds among transition metal oxides
because of its heavy fermion like behavior at low temperatures. In this paper
we present results for the orbital state and magnetic properties of LiV_2 O_4
obtained from a combination of density functional theory within the local
density approximation and dynamical mean-field theory (DMFT). The DMFT
equations are solved by quantum Monte Carlo simulations. The trigonal crystal
field splits the V 3d orbitals such that the a_{1g} and e_{g}^{pi} orbitals
cross the Fermi level, with the former being slightly lower in energy and
narrower in bandwidth. In this situation, the d-d Coulomb interaction leads to
an almost localization of one electron per V ion in the a_{1g} orbital, while
the e_{g}^{pi} orbitals form relatively broad bands with 1/8 filling. 2The
theoretical high-temperature paramagnetic susceptibility chi(T) follows a
Curie-Weiss law with an effective paramagnetic moment p_{eff}=1.65 in agreement
with the experimental results.Comment: 11 pages, 10 figures, 2 table
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