318 research outputs found
Sleep problems for children with autism and caregiver spillover effects
Sleep problems in children with autism spectrum disorders (ASD) are under-recognized and under-treated. Identifying treatment value accounting for health effects on family members (spillovers) could improve the perceived cost-effectiveness of interventions to improve child sleep habits. A prospective cohort study (N = 224) was conducted with registry and postal survey data completed by the primary caregiver.Wecalculated quality of life outcomes for the child and the primary caregiver associated with treatments to improve sleep in the child based on prior clinical trials. Predicted treatment effects for melatonin and behavioral interventions were similar in magnitude for the child and for the caregiver. Accounting for caregiver spillover effects associated with treatments for the child with ASD increases treatment benefits and improves cost-effectiveness profiles
Quantum Mass and Central Charge of Supersymmetric Monopoles - Anomalies, current renormalization, and surface terms
We calculate the one-loop quantum corrections to the mass and central charge
of N=2 and N=4 supersymmetric monopoles in 3+1 dimensions. The corrections to
the N=2 central charge are finite and due to an anomaly in the conformal
central charge current, but they cancel for the N=4 monopole. For the quantum
corrections to the mass we start with the integral over the expectation value
of the Hamiltonian density, which we show to consist of a bulk contribution
which is given by the familiar sum over zero-point energies, as well as surface
terms which contribute nontrivially in the monopole sector. The bulk
contribution is evaluated through index theorems and found to be nonvanishing
only in the N=2 case. The contributions from the surface terms in the
Hamiltonian are cancelled by infinite composite operator counterterms in the
N=4 case, forming a multiplet of improvement terms. These counterterms are also
needed for the renormalization of the central charge. However, in the N=2 case
they cancel, and both the improved and the unimproved current multiplet are
finite.Comment: 1+40 pages, JHEP style. v2: small corrections and additions,
references adde
N=1* model and glueball superpotential from Renormalization-Group-improved perturbation theory
A method for computing the low-energy non-perturbative properties of SUSY
GFT, starting from the microscopic lagrangian model, is presented. The method
relies on covariant SUSY Feynman graph techniques, adapted to low energy, and
Renormalization-Group-improved perturbation theory. We apply the method to
calculate the glueball superpotential in N=1 SU(2) SYM and obtain a potential
of the Veneziano-Yankielowicz type.Comment: 19 pages, no figures; added references; note added at the end of the
paper; version to appear in JHE
Hybrid Monte Carlo with Fat Link Fermion Actions
The use of APE smearing or other blocking techniques in lattice fermion
actions can provide many advantages. There are many variants of these fat link
actions in lattice QCD currently, such as FLIC fermions. The FLIC fermion
formalism makes use of the APE blocking technique in combination with a
projection of the blocked links back into the special unitary group. This
reunitarisation is often performed using an iterative maximisation of a gauge
invariant measure. This technique is not differentiable with respect to the
gauge field and thus prevents the use of standard Hybrid Monte Carlo simulation
algorithms. The use of an alternative projection technique circumvents this
difficulty and allows the simulation of dynamical fat link fermions with
standard HMC and its variants. The necessary equations of motion for FLIC
fermions are derived, and some initial simulation results are presented. The
technique is more general however, and is straightforwardly applicable to other
smearing techniques or fat link actions
Associations between energy intake, daily food intake and energy density of foods and BMI z-score in 2-9-year-old European children
The aim of this study was to investigate the associations between proxy-reported energy intake, daily food intake and energy density of foods and body mass index (BMI) z-score in 2-9-year-old European children.
From 16,225 children who participated in the identification and prevention of dietary- and lifestyle-induced health effects in children and infants (IDEFICS) baseline examination, 9,782 children with 24-h proxy dietary information and complete covariate information were included in the analysis. Participating children were classified according to adapted Goldberg cutoffs: underreports, plausible energy reports and overreports. Energy intake, daily food intake and energy density of foods excluding noncaloric beverages were calculated for all eating occasions. Effect of energy intake, daily food intake and energy density of foods on BMI z-score was investigated using multilevel regression models in the full sample and subsample of plausible energy reports. Exposure variables were included separately; daily food intake and energy intake were addressed in a combined model to check for interactions.
In the group of plausible energy reports (N = 8,544), energy intake and daily food intake were significantly positively associated with BMI z-score. Energy density of foods was not associated with BMI z-score. In the model including energy intake, food intake and an interaction term, only energy intake showed a significantly positive effect on BMI z-score. In the full sample (N = 9,782), only energy intake was significantly but negatively associated with BMI z-score.
Proxy-reporters are subject to misreporting, especially for children in the higher BMI levels. Energy intake is a more important predictor of unhealthy weight development in children than daily food intake
Non-perturbative contributions to the plane-wave string mass matrix
D-instanton contributions to the mass matrix of arbitrary excited string
states of type IIB string theory in the maximally supersymmetric plane-wave
background are calculated to leading order in the string coupling using a
supersymmetric light-cone boundary state formalism. The explicit
non-perturbative dependence of the mass matrix on the complex string coupling,
the plane-wave mass parameter and the mode numbers of the excited states is
determined.Comment: 25 pages, 1 figure. v3: corrected minor typos, added referenc
Non-perturbative effects in the BMN limit of N=4 supersymmetric Yang-Mills
One-instanton contributions to the correlation functions of two
gauge-invariant single-trace operators in N=4 SU(N) Yang-Mills theory are
studied in semi-classical approximation in the BMN limit. The most
straightforward examples involve operators with four bosonic impurities. The
explicit form for the correlation functions, which determine the anomalous
dimensions, follows after integration over the large number of bosonic and
fermionic moduli. Our results demonstrate that the instanton contributions
scale appropriately in the BMN limit. We find impressive agreement with the
D-instanton contributions to mass matrix elements of the dual plane-wave IIB
superstring theory, obtained in a previous paper. Not only does the dependence
on the scaled coupling constants match, but the dependence on the mode numbers
of the states is also in striking agreement.Comment: 52 pages, no figures, latex; V2: minor change
Fixed twist dynamics of SO(3) gauge theory
We perform a throughout study of 3+1 dim. SO(3) LGT for any fixed-twist
background. We concentrate in particular on the physically significant trivial
and 1-twist sectors. Introducing a Z(2) monopole chemical potential the 1st
order bulk transition is moved down in the strong coupling region and weakened
to 2nd order in the 4-dim Ising model universality class. In this extended
phase diagram we gain access to a confined phase in every fixed twist sector of
the theory. The Pisa disorder operator is employed together with the Polyakov
loop to study the confinement-deconfinement transition in each sector. Due to
the specific properties of both operators, most results can be used to gain
insight in the ergodic theory, where all twist sectors should be summed upon.
An explicit mapping of each fixed twist theory to effective positive plaquette
models with fixed twisted boundary conditions is applied to better establish
their properties in the different phases.Comment: 20 pages, 11 Figures. Minor changes in text and figures, to appear in
Eur.Phys.J.
On the spectrum of AdS/CFT beyond supergravity
We test the spectrum of string theory on AdS_5 x S^5 derived in
hep-th/0305052 against that of single-trace gauge invariant operators in free
N=4 super Yang-Mills theory. Masses of string excitations at critical tension
are derived by extrapolating plane-wave frequencies at g_{YM}=0 down to finite
J. On the SYM side, we present a systematic description of the spectrum of
single-trace operators and its reduction to PSU(2,2|4) superconformal primaries
via a refined Eratostenes' supersieve. We perform the comparison of the
resulting SYM/string spectra of charges and multiplicities order by order in
the conformal dimension \Delta up to \Delta=10 and find perfect agreement.
Interestingly, the SYM/string massive spectrum exhibits a hidden symmetry
structure larger than expected, with bosonic subgroup SO(10,2) and thirty-two
supercharges.Comment: 28 pages, LaTeX2
Twistor Strings with Flavour
We explore the tree-level description of a class of N=2 UV-finite SYM
theories with fundamental flavour within a topological B-model twistor string
framework. In particular, we identify the twistor dual of the Sp(N) gauge
theory with one antisymmetric and four fundamental hypermultiplets, as well as
that of the SU(N) theory with 2N hypermultiplets. This is achieved by suitably
orientifolding/orbifolding the original N=4 setup of Witten and adding a
certain number of new topological 'flavour'-branes at the orientifold/orbifold
fixed planes to provide the fundamental matter. We further comment on the
appearance of these objects in the B-model on CP(3|4). An interesting aspect of
our construction is that, unlike the IIB description of these theories in terms
of D3 and D7-branes, on the twistor side part of the global flavour symmetry is
realised geometrically. We provide evidence for this correspondence by
calculating and matching amplitudes on both sides.Comment: 38+12 pages; uses axodraw.sty. v2: References added, minor
clarification
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