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2D3D2D: a diagnostic approach to textile and fashion research practice
In the School of Art and Design, at Nottingham Trent University, a range of research methods and practices have developed through PhD and post doctoral study in relation to printed textile design and new technology. Individual research projects have addressed pattern (Bunce 1993); photographic imagery (Briggs 1997); colour (Leak 2001); non-repeating pattern (Carlisle 2003) and 2D/3D (Townsend 2003). Post-doctoral research (Briggs-Goode & Bunce 2001) and Townsend's research into 2D/3D informed a group project and exhibition Transforming Shape (2004). The outcomes created by Gillian Bunce, Amanda Briggs-Goode, Gillian Bunce, Rosemary Goulding and Katherine Townsend explored the relationships between innovative surface imagery and three-dimensional prototypes, based on the simple geometric forms of square, rectangle and circle
Superconformal mechanics, black holes, and non-linear realizations
The OSp(2|2)-invariant planar dynamics of a D=4 superparticle near the
horizon of a large mass extreme black hole is described by an N=2
superconformal mechanics, with the SO(2) charge being the superparticle's
angular momentum. The {\it non-manifest} superconformal invariance of the
superpotential term is shown to lead to a shift in the SO(2) charge by the
value of its coefficient, which we identify as the orbital angular momentum.
The full SU(1,1|2)-invariant dynamics is found from an extension to N=4
superconformal mechanics.Comment: 19 pages, plain latex file. Slightly shortened version, two
references adde
N=1 Non-Abelian Tensor Multiplet in Four Dimensions
We carry out the N=1 supersymmetrization of a physical non-Abelian tensor
with non-trivial consistent couplings in four dimensions. Our system has three
multiplets: (i) The usual non-Abelian vector multiplet (VM) (A_\mu{}^I,
\lambda^I), (ii) A non-Abelian tensor multiplet (TM) (B_{\mu\nu}{}^I, \chi^I,
\varphi^I), and (iii) A compensator vector multiplet (CVM) (C_\mu{}^I, \rho^I).
All of these multiplets are in the adjoint representation of a non-Abelian
group G. Unlike topological theory, all of our fields are propagating with
kinetic terms. The C_\mu{}^I-field plays the role of a Stueckelberg compensator
absorbed into the longitudinal component of B_{\mu\nu}{}^I. We give not only
the component lagrangian, but also a corresponding superspace reformulation,
reconfirming the total consistency of the system. The adjoint representation of
the TM and CVM is further generalized to an arbitrary real representation of
general SO(N) gauge group. We also couple the globally N=1 supersymmetric
system to supergravity, as an additional non-trivial confirmation.Comment: 18 pages, no figur
Manejo de pastagem.
Este folder apresenta informaçÔes båsicas sobre manejo de pastagem: o objetivo do manejo de pastagem; sistemas de pastejo; taxa de lotação; pressão do pastejo, capacidade de suportebitstream/CPAF-RO-2010/14520/1/folder-pastagem.pdfFolder
Cosmology as Geodesic Motion
For gravity coupled to N scalar fields with arbitrary potential V, it is
shown that all flat (homogeneous and isotropic) cosmologies correspond to
geodesics in an (N+1)-dimensional `augmented' target space of Lorentzian
signature (1,N), timelike if V>0, null if V=0 and spacelike if V<0.
Accelerating cosmologies correspond to timelike geodesics that lie within an
`acceleration subcone' of the `lightcone'. Non-flat (k=-1,+1) cosmologies are
shown to evolve as projections of geodesic motion in a space of dimension
(N+2), of signature (1,N+1) for k=-1 and signature (2,N) for k=+1. This
formalism is illustrated by cosmological solutions of models with an
exponential potential, which are comprehensively analysed; the late-time
behviour for other potentials of current interest is deduced by comparison.Comment: 26 pages, 2 figures, journal version with additional reference
Scaling Cosmologies of N=8 Gauged Supergravity
We construct exact cosmological scaling solutions in N=8 gauged supergravity.
We restrict to solutions for which the scalar fields trace out geodesic curves
on the scalar manifold. Under these restrictions it is shown that the axionic
scalars are necessarily constant. The potential is then a sum of exponentials
and has a very specific form that allows for scaling solutions. The scaling
solutions describe eternal accelerating and decelerating power-law universes,
which are all unstable. An uplift of the solutions to 11-dimensional
supergravity is carried out and the resulting timedependent geometries are
discussed. In the discussion we briefly comment on the fact that N=2 gauged
supergravity allows stable scaling solutions.Comment: 17 pages; referenced added, reportnr changed and some corrections in
section
Quantum cryptography with squeezed states
A quantum key distribution scheme based on the use of displaced squeezed
vacuum states is presented. The states are squeezed in one of two field
quadrature components, and the value of the squeezed component is used to
encode a character from an alphabet. The uncertainty relation between
quadrature components prevents an eavesdropper from determining both with
enough precision to determine the character being sent. Losses degrade the
performance of this scheme, but it is possible to use phase-sensitive
amplifiers to boost the signal and partially compensate for their effect.Comment: 15 pages, no figure
Misreporting of Dietary Intake Affects Estimated Nutrient Intakes in Low-Income Spanish-Speaking Women
Misreporting of dietary intake affects the validity of data collected and conclusions drawn in studies exploring diet and health outcomes. One consequence of misreporting is biological implausibility. Little is known regarding how accounting for biological implausibility of reported intake affects nutrient intake estimates in Hispanics, a rapidly growing demographic in the United States. Our study explores the effect of accounting for plausibility on nutrient intake estimates in a sample of Mexican-American women in northern California in 2008. Nutrient intakes are compared with Dietary Reference Intake recommendations, and intakes of Mexican-American women in a national survey are presented as a reference. Eighty-two women provided three 24-hour recalls. Reported energy intakes were classified as biologically plausible or implausible using the reported energy intakes to total energy expenditure cutoff of 1.24, with low-active physical activity levels used to estimate total energy expenditure. Differences in the means of nutrient intakes between implausible (n=36) and plausible (n=46) reporters of energy intake were examined by bivariate linear regression. Estimated energy, protein, cholesterol, dietary fiber, and vitamin E intakes were significantly higher in plausible reporters than implausible. There was a significant difference between the proportions of plausible vs implausible reporters meeting recommendations for several nutrients, with a larger proportion of plausible reporters meeting recommendations. Further research related to misreporting in Hispanic populations is warranted to explore the causes and effects of misreporting in studies measuring dietary intake, as well as actions to be taken to prevent or account for this issue
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