5,911 research outputs found
Living with the user: Design drama for dementia care through responsive scripted experiences in the home
Participation in forms of drama and narrative can provoke empathy and creativity in user-centred design processes. In this paper, we expand upon existing methods to explore the potential for responsive scripted experiences that are delivered through the combination of sensors and output devices placed in a home. The approach is being developed in the context of Dementia care, where the capacity for rich user participation in design activities is limited. In this case, a system can act as a proxy for a person with Dementia, allowing designers to gain experiences and insight as to what it is like to provide care for, and live with, this person. We describe the rationale behind the approach, a prototype system architecture, and our current work to explore the creation of scripted experiences for design, played out though UbiComp technologies.This research is funded by the Arts and Humanities Research Council UK, (AH/K00266X/1) and Horizon Digital Economy Research (RCUK grant EP/G065802/1)
A circuit logic for sexually shared and dimorphic aggressive behaviors in Drosophila
Aggression involves both sexually monomorphic and dimorphic actions. How the brain implements these two types of actions is poorly understood. We have identified three cell types that regulate aggression in Drosophila: one type is sexually shared, and the other two are sex specific. Shared common aggression-promoting (CAP) neurons mediate aggressive approach in both sexes, whereas functionally downstream dimorphic but homologous cell types, called male-specific aggression-promoting (MAP) neurons in males and fpC1 in females, control dimorphic attack. These symmetric circuits underlie the divergence of male and female aggressive behaviors, from their monomorphic appetitive/motivational to their dimorphic consummatory phases. The strength of the monomorphic â dimorphic functional connection is increased by social isolation in both sexes, suggesting that it may be a locus for isolation-dependent enhancement of aggression. Together, these findings reveal a circuit logic for the neural control of behaviors that include both sexually monomorphic and dimorphic actions, which may generalize to other organisms
Cosmology with a TeV mass GUT Higgs
The most natural way to break the GUT gauge symmetry is with a Higgs field
whose vacuum expectation value is of order 10^{16}\,\mbox{GeV} but whose mass
is of order to 10^3\,\mbox{GeV}. This can lead to a cosmological
history radically different from what is usually assumed to have occurred
between the standard inflationary and nucleosynthesis epochs, which may solve
the gravitino and Polonyi/moduli problems in a natural way.Comment: 4 pages, revte
Brighter prospects? Assessing the franchise advantage using census data
This paper uses Census micro data to examine how starting a business as a franchise rather than an independent business affects its survival and growth prospects. We assess factors that influence the decision to become a franchisee and use various empirical approaches to correct for selection bias in our performance analyses. We find that franchised businesses on average exhibit higher survival rates than independent businesses, but importantly, the difference is small compared to claims in the trade press. The effect is also short lived: conditional on surviving a year or two, we no longer find survival (or growth) differences. We then explore two potential sources for this small survival advantage, namely franchisorsâ screening process and the benefits arising from the brand and business know-how provided by franchisors. We find evidence that both of the sources contribute to the franchising advantage
A Model of Direct Gauge Mediation
We present a simple model of gauge mediation (GM) which does not have a
messenger sector or gauge singlet fields. The standard model gauge groups
couple directly to the sector which breaks supersymmetry dynamically. This is
the first phenomenologically viable example of this type in the literature.
Despite the direct coupling, the model can preserve perturbative gauge
unification. This is achieved by the inverted hierarchy mechanism which
generates a large scalar expectation value compared to the size of
supersymmetry breaking. There is no dangerous negative contribution to the
squark, slepton masses due to two-loop renormalization group equation. The
potentially non-universal supergravity contribution to the scalar masses can be
suppressed enough to maintain the virtue of the gauge mediation. The model is
completely chiral, and one does not need to forbid mass terms for the messenger
fields by hand. Beyond the simplicity of the model, it possesses cosmologically
desirable features compared to the original models of GM: an improved gravitino
and string moduli cosmology. The Polonyi problem is back unlike in the original
GM models, but is still much less serious than in hidden sector models.Comment: LaTeX, 12 page
Thermal Inflation and the Moduli Problem
In supersymmetric theories a field can develop a vacuum expectation value , even though its mass is of order to
. The finite temperature in the early Universe can hold such a
field at zero, corresponding to a false vacuum with energy density . When the temperature falls below , the thermal energy
density becomes negligible and an era of thermal inflation begins. It ends when
the field rolls away from zero at a temperature of order , corresponding to
of order 10 -folds of inflation which does not affect the density
perturbation generated during ordinary inflation. Thermal inflation can solve
the Polonyi/moduli problem if is within one or two orders of magnitude of
.Comment: Revised version to appear in Phys Rev D. Improved discussion of the
possible effect of parametric resonance. Latex, 31 page
The Cosmological Moduli Problem, Supersymmetry Breaking and Stability in Postinflationary Cosmology
A survey of solutions to the cosmological moduli problem in string theory.
The only extant proposal which may work is Intermediate Scale Inflation as
proposed by Randall and Thomas. Supersymmetry preserving dynamics which could
give large masses to the moduli is strongly constrained by cosmology and
requires the existence of string vacuum states possessing properties different
from those of any known vacuuum. Such a mechanism cannot give mass to the
dilaton unless there are cancellations between different exponentially small
contributions to the superpotential. Our investigation also shows that
stationary points of the effective potential with negative vacuum energy do not
correspond to stationary solutions of the equations of postinflationary
cosmology. This suggests that supersymmetry breaking is a requirement for a
successful inflationary cosmology.Comment: harvma
Inflation and flat directions in modular invariant superstring effective theories
The potential during inflation must be very flat in, at least, the direction
of the inflaton. In renormalizable global supersymmetry, flat directions are
ubiquitous, but they are not preserved in a generic supergravity theory. It is
known that at least some of them are preserved in no-scale supergravity, and
simple generalizations of it. We here study a more realistic generalization,
based on string-derived supergravity, using the linear supermultiplet formalism
for the dilaton. We consider a general class of hybrid inflation models, where
a Fayet-Illiopoulos term drives some fields to large values. The potential
is dominated by the term, but flatness is preserved in some directions.
This allows inflation, with the dilaton stabilized in its domain of attraction,
and some moduli stabilized at their vacuum values. Another modulus may be the
inflaton.Comment: 19 pages, REVTEX, further typos, refs fixe
Spectrum of Background X-rays from Moduli Dark Matter
We examine the -ray spectrum from the decay of the dark-matter moduli with
mass keV, in particular, paying attention to the line
spectrum from the moduli trapped in the halo of our galaxy. It is found that
with the energy resolution of the current experiments (%) the line
intensity is about twice stronger than that of the continuum spectrum from the
moduli that spread in the whole universe. Therefore, in the future experiments
with higher energy resolutions it may be possible to detect such line photons.
We also investigate the -ray spectrum emitted from the decay of the
multi-GeV moduli. It is shown that the emitted photons may form MeV-bump in the
-ray spectrum. We also find that if the modulus mass is of the order of
10 GeV, the emitted photons at the peak of the continuum spectrum loses their
energy by the scattering and the shape of the spectrum is significantly
changed, which makes the constraint weaker than that obtained in the previous
works.Comment: 14 pages (RevTeX file) including four postscript figures, reviced
version to be published in Physical Review
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