1,677 research outputs found
Weight gain and dietary intake during pregnancy in industrialized countries - a systematic review of observational studies
Background: Gestational weight gain (GWG) above the recently recommended ranges is likely to be related to adverse pregnancy outcomes and therefore a challenge in industrialized countries. Aims: We conducted a systematic review on observational studies in order to gain more evidence on whether diets with lower caloric/protein content or other diets might be associated with lower GWG. Methods: We searched in MEDLINE and EMBASE for observational studies written in English or German reporting associations between diet and GWG in singleton pregnancies of healthy women in industrialized countries. Results: We identified 12 studies which met the inclusion criteria. Five studies suggested significant positive associations between energy intake and GWG, whereas three found no significant association. Further significant positive associations of GWG were reported with respect to protein intake, animal lipids, energy density and a number of different food servings per day, whereas intake of carbohydrates and vegetarian diet were associated with less GWG. Conclusions: We suggest that GWG might be reduced by lower energy intake in pregnancy
Field Representations of Vector Supersymmetry
We study some field representations of vector supersymmetry with superspin
Y=0 and Y=1/2 and nonvanishing central charges. For Y=0, we present two
multiplets composed of four spinor fields, two even and two odd, and we provide
a free action for them. The main differences between these two multiplets are
the way the central charge operators act and the compatibility with the
Majorana reality condition on the spinors. One of the two is related to a
previously studied spinning particle model. For Y=1/2, we present a multiplet
composed of one even scalar, one odd vector and one even selfdual two-form,
which is a truncation of a known representation of the tensor supersymmetry
algebra in Euclidean spacetime. We discuss its rotation to Minkowski spacetime
and provide a set of dynamical equations for it, which are however not derived
from a Lagrangian. We develop a superspace formalism for vector supersymmetry
with central charges and we derive our multiplets by superspace techniques.
Finally, we discuss some representations with vanishing central charges.Comment: 37 page
Trotter-Kato product formulae in Dixmier ideal
It is shown that for a certain class of the Kato functions the Trotter-Kato
product formulae converge in Dixmier ideal C 1, in topology, which is
defined by the 1,-norm. Moreover, the rate of convergence in
this topology inherits the error-bound estimate for the corresponding
operator-norm convergence. 1 since [24], [14]. Note that a subtle point of this
program is the question about the rate of convergence in the corresponding
topology. Since the limit of the Trotter-Kato product formula is a strongly
continuous semigroup, for the von Neumann-Schatten ideals this topology is the
trace-norm 1 on the trace-class ideal C 1 (H). In this case the limit
is a Gibbs semigroup [25]. For self-adjoint Gibbs semigroups the rate of
convergence was estimated for the first time in [7] and [9]. The authors
considered the case of the Gibbs-Schr{\"o}dinger semigroups. They scrutinised
in these papers a dependence of the rate of convergence for the (exponential)
Trotter formula on the smoothness of the potential in the Schr{\"o}dinger
generator. The first abstract result in this direction was due to [19]. In this
paper a general scheme of lifting the operator-norm rate convergence for the
Trotter-Kato product formulae was proposed and advocated for estimation the
rate of the trace-nor
Ergodic Jacobi matrices and conformal maps
We study structural properties of the Lyapunov exponent and the
density of states for ergodic (or just invariant) Jacobi matrices in a
general framework. In this analysis, a central role is played by the function
as a conformal map between certain domains. This idea goes
back to Marchenko and Ostrovskii, who used this device in their analysis of the
periodic problem
A national survey of services for the prevention and management of falls in the UK
Background: The National Health Service (NHS) was tasked in 2001 with developing service provision to prevent falls in older people. We carried out a national survey to provide a description of health and social care funded UK fallers services, and to benchmark progress against current
practice guidelines.
Methods: Cascade approach to sampling, followed by telephone survey with senior member of the fall service. Characteristics of the service were assessed using an internationally agreed taxonomy. Reported service provision was compared against benchmarks set by the National
Institute for Health and Clinical Excellence (NICE).
Results: We identified 303 clinics across the UK. 231 (76%) were willing to participate. The majority of services were based in acute or community hospitals, with only a few in primary care or emergency departments. Access to services was, in the majority of cases, by health professional
referral. Most services undertook a multi-factorial assessment. The content and quality of these assessments varied substantially. Services varied extensively in the way that interventions were delivered, and particular concern is raised about interventions for vision, home hazard modification, medication review and bone health.
Conclusion: The most common type of service provision was a multi-factorial assessment and intervention. There were a wide range of service models, but for a substantial number of services, delivery appears to fall below recommended NICE guidance
An Integrand Reconstruction Method for Three-Loop Amplitudes
We consider the maximal cut of a three-loop four point function with massless
kinematics. By applying Groebner bases and primary decomposition we develop a
method which extracts all ten propagator master integral coefficients for an
arbitrary triple-box configuration via generalized unitarity cuts. As an
example we present analytic results for the three loop triple-box contribution
to gluon-gluon scattering in Yang-Mills with adjoint fermions and scalars in
terms of three master integrals.Comment: 15 pages, 1 figur
Hepta-Cuts of Two-Loop Scattering Amplitudes
We present a method for the computation of hepta-cuts of two loop scattering
amplitudes. Four dimensional unitarity cuts are used to factorise the integrand
onto the product of six tree-level amplitudes evaluated at complex momentum
values. Using Gram matrix constraints we derive a general parameterisation of
the integrand which can be computed using polynomial fitting techniques. The
resulting expression is further reduced to master integrals using conventional
integration by parts methods. We consider both planar and non-planar topologies
for 2 to 2 scattering processes and apply the method to compute hepta-cut
contributions to gluon-gluon scattering in Yang-Mills theory with adjoint
fermions and scalars.Comment: 37 pages, 6 figures. version 2 : minor updates, published versio
Taurolidine-citrate lock solution (TauroLock) significantly reduces CVAD-associated grampositive infections in pediatric cancer patients
<p>Abstract</p> <p>Background</p> <p>Taurolidin/Citrate (TauroLock™), a lock solution with broad spectrum antimicrobial activity, may prevent bloodstream infection (BSI) due to coagulase-negative staphylococci (CoNS or 'MRSE' in case of methicillin-resistant isolates) in pediatric cancer patients with a long term central venous access device (CVAD, Port- or/Broviac-/Hickman-catheter type).</p> <p>Methods</p> <p>In a single center prospective 48-months cohort study we compared all patients receiving anticancer chemotherapy from April 2003 to March 2005 (group 1, heparin lock with 200 IU/ml sterile normal saline 0.9%; Canusal<sup>® </sup>Wockhardt UK Ltd, Wrexham, Wales) and all patients from April 2005 to March 2007 (group 2; taurolidine 1.35%/Sodium Citrate 4%; TauroLock™, Tauropharm, Waldbüttelbrunn, Germany).</p> <p>Results</p> <p>In group 1 (heparin), 90 patients had 98 CVAD in use during the surveillance period. 14 of 30 (47%) BSI were 'primary Gram positive BSI due to CoNS (n = 4) or MRSE (n = 10)' [incidence density (ID); 2.30 per 1000 inpatient CVAD-utilization days].</p> <p>In group 2 (TauroLock™), 89 patients had 95 CVAD in use during the surveillance period. 3 of 25 (12%) BSI were caused by CoNS. (ID, 0.45). The difference in the ID between the two groups was statistically significant (P = 0.004).</p> <p>Conclusion</p> <p>The use of Taurolidin/Citrate (TauroLock™) significantly reduced the number and incidence density of primary catheter-associated BSI due to CoNS and MRSE in pediatric cancer patients.</p
Qubit portrait of the photon-number tomogram and separability of two-mode light states
In view of the photon-number tomograms of two-mode light states, using the
qubit-portrait method for studying the probability distributions with infinite
outputs, the separability and entanglement detection of the states are studied.
Examples of entangled Gaussian state and Schr\"{o}dinger cat state are
discussed.Comment: 20 pages, 6 figures, TeX file, to appear in Journal of Russian Laser
Researc
A Survey on the Krein-von Neumann Extension, the corresponding Abstract Buckling Problem, and Weyl-Type Spectral Asymptotics for Perturbed Krein Laplacians in Nonsmooth Domains
In the first (and abstract) part of this survey we prove the unitary
equivalence of the inverse of the Krein--von Neumann extension (on the
orthogonal complement of its kernel) of a densely defined, closed, strictly
positive operator, for some in a Hilbert space to an abstract buckling problem operator.
This establishes the Krein extension as a natural object in elasticity theory
(in analogy to the Friedrichs extension, which found natural applications in
quantum mechanics, elasticity, etc.).
In the second, and principal part of this survey, we study spectral
properties for , the Krein--von Neumann extension of the
perturbed Laplacian (in short, the perturbed Krein Laplacian)
defined on , where is measurable, bounded and
nonnegative, in a bounded open set belonging to a
class of nonsmooth domains which contains all convex domains, along with all
domains of class , .Comment: 68 pages. arXiv admin note: extreme text overlap with arXiv:0907.144
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