13,561 research outputs found
E11, generalised space-time and equations of motion in four dimensions
We construct the non-linear realisation of the semi-direct product of E11 and
its first fundamental representation at low levels in four dimensions. We
include the fields for gravity, the scalars and the gauge fields as well as the
duals of these fields. The generalised space-time, upon which the fields
depend, consists of the usual coordinates of four dimensional space-time and
Lorentz scalar coordinates which belong to the 56-dimensional representation of
E7. We demand that the equations of motion are first order in derivatives of
the generalised space-time and then show that they are essentially uniquely
determined by the properties of the E11 Kac-Moody algebra and its first
fundamental representation. The two lowest equations correctly describe the
equations of motion of the scalars and the gauge fields once one takes the
fields to depend only on the usual four dimensional space-time
The acute influence of sucrose consumption with and without vitamin C co-ingestion on microvascular reactivity in healthy young adults
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.  Background
Sugar sweetened beverages (SSB) are a major source of dietary sugar and a public health concern. Glucose consumption acutely influences microvascular reactivity in healthy adults, possibly via oxidative stress. The purpose of this study was to observe the acute influence of a more relevant dose of sucrose on microvascular reactivity, and to identify whether this response is influenced by the amount of vitamin C typically contained in SSB.
Methods
Thirteen ostensibly healthy adults (8 male, 5 female) performed three 1-day trials in a randomized order; the consumption of 300 ml water (control; CON), or 300 ml water with 50 g sucrose (SUGAR) or 50 g sucrose with 160 mg of vitamin C (VITC). Near infrared spectroscopy was used to determine peak reactive hyperaemia (PRH), the rate of desaturation (Slope 1) and reperfusion (Slope 2), and the total area under the reperfusion curve versus time (TRH) following 5 min of forearm cuff occlusion before and 30, 60, 90 and 120 min after test drink consumption.
Results
SUGAR and VITC significantly increased the total area under the curve versus time for plasma glucose (P < 0.05 for both). No changes in microvascular reactivity were observed between trials, although VITC increased Slope 1 compared to both SUGAR and CON 30 and 60 min post drink (P < 0.05 for both).
Conclusion
The consumption of a sugar load representative of commercially available SSB did not influence microvascular reactivity. The co-ingestion of Vitamin C also failed to influence microvascular reactivity, but did increase the rate of oxygen extraction
The local symmetries of M-theory and their formulation in generalised geometry
In the doubled field theory approach to string theory, the T-duality group is
promoted to a manifest symmetry at the expense of replacing ordinary Riemannian
geometry with generalised geometry on a doubled space. The local symmetries are
then given by a generalised Lie derivative and its associated algebra. This
paper constructs an analogous structure for M-theory. A crucial by-product of
this is the derivation of the physical section condition for M-theory
formulated in an extended space.Comment: 20 pages, v2: Author Name corrected, v3: typos correcte
Coulomb-hadron phase factor and spin phenomena in a wide region of transfer momenta
The Coulomb-hadron interference effects are examined at small and large .
The methods for the definition of spin-dependent parts of hadron scattering
amplitude are presented. The additional contributions to analyzing power
and the double spin correlation parameter owing to the
electromagnetic-hadron interference are determined in the diffraction dip
domain of high-energy elastic hadron scattering.Comment: 9 pages, LaTeX, 4 figure
Spin-charge separation and localization in one-dimension
We report on measurements of quantum many-body modes in ballistic wires and
their dependence on Coulomb interactions, obtained from tunneling between two
parallel wires in a GaAs/AlGaAs heterostructure while varying electron density.
We observe two spin modes and one charge mode of the coupled wires, and map the
dispersion velocities of the modes down to a critical density, at which
spontaneous localization is observed. Theoretical calculations of the charge
velocity agree well with the data, although they also predict an additional
charge mode that is not observed. The measured spin velocity is found to be
smaller than theoretically predicted.Comment: There are minor textual differences between this version and the
version that has been published in Science (follow the DOI link below to
obtain it). In addition, here we have had to reduce figure quality to save
space on the serve
Correlation Functions of Conserved Currents in N = 2 Superconformal Theory
Using a manifestly supersymmetric formalism, we determine the general
structure of two- and three- point functions of the supercurrent and the
flavour current of N = 2 superconformal field theories. We also express them in
terms of N = 1 superfields and compare to the generic N = 1 correlation
functions. A general discussion of the N = 2 supercurrent superfield and the
multiplet of anomalies and their definition as derivatives with respect to the
supergravity prepotentials is also included.Comment: 43 pages, latex, no figures, v.2: section 4.2 extende
Interpretation of y-scaling of the nuclear response
The behavior of the nuclear matter response in the region of large momentum
transfer, in which plane wave impulse approximation predicts the onset of
y-scaling, is discussed. The theoretical analysis shows that scaling violations
produced by final state interactions are driven by the momentum dependence of
the nucleon-nucleon scattering cross section.
Their study may provide valuable information on possible modifications of
nucleon-nucleon scattering in the nuclear medium.Comment: 4 pages with 3 figures. To appear in Physical Review Letter
A Note on E11 and Three-dimensional Gauged Supergravity
We determine the gauge symmetries of all p-forms in maximal three-dimensional
gauged supergravity by requiring invariance of the Lagrangian. It is shown that
in a particular ungauged limit these symmetries are in precise correspondence
to those predicted by the very-extended Kac-Moody algebra E11. We demonstrate
that whereas in the ungauged limit the bosonic gauge algebra closes off-shell,
the closure is only on-shell in the full gauged theory. This underlines the
importance of dynamics for understanding the Kac-Moody origin of the symmetries
of gauged supergravity.Comment: Published versio
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