2,869 research outputs found
Designing a mobile augmented memory system for people with traumatic brain injuries
Augmented memory systems help people remember events in their lives. Individuals with Traumatic Brain Injury (TBI) often have memory impairments. We conducted a user study to learn about strategies individuals with TBI use to remember events in their lives. We explored what characteristics individuals with TBI expect of an augmented memory system. We then investigated these aspects in an initial mobile app design, and propose here a concept for a rehearsal application that addresses the issues found in our studies
M2-Branes and Background Fields
We discuss the coupling of multiple M2-branes to the background 3-form and
6-form gauge fields of eleven-dimensional supergravity, including the coupling
of the Fermions. In particular we show in detail how a natural generalization
of the Myers flux-terms, along with the resulting curvature of the background
metric, leads to mass terms in the effective field theory.Comment: 19 page
Lattice simulations with eight flavors of domain wall fermions in SU(3) gauge theory
We study an SU(3) gauge theory with Nf=8 degenerate flavors of light fermions
in the fundamental representation. Using the domain wall fermion formulation,
we investigate the light hadron spectrum, chiral condensate and electroweak S
parameter. We consider a range of light fermion masses on two lattice volumes
at a single gauge coupling chosen so that IR scales approximately match those
from our previous studies of the two- and six-flavor systems. Our results for
the Nf=8 spectrum suggest spontaneous chiral symmetry breaking, though fits to
the fermion mass dependence of spectral quantities do not strongly disfavor the
hypothesis of mass-deformed infrared conformality. Compared to Nf=2 we observe
a significant enhancement of the chiral condensate relative to the symmetry
breaking scale F, similar to the situation for Nf=6. The reduction of the S
parameter, related to parity doubling in the vector and axial-vector channels,
is also comparable to our six-flavor results
Optically assembled droplet interface bilayer (OptiDIB) networks from cell-sized microdroplets
We report a new platform technology to systematically assemble droplet interface bilayer (DIB) networks in user-defined 3D architectures from cell-sized droplets using optical tweezers. Our OptiDIB platform is the first demonstration of optical trapping to precisely construct 3D DIB networks, paving the way for the development of a new generation of modular bio-systems
Stealth Dark Matter: Dark scalar baryons through the Higgs portal
We present a new model of "Stealth Dark Matter": a composite baryonic scalar
of an strongly-coupled theory with even . All mass scales
are technically natural, and dark matter stability is automatic without
imposing an additional discrete or global symmetry. Constituent fermions
transform in vector-like representations of the electroweak group that permit
both electroweak-breaking and electroweak-preserving mass terms. This gives a
tunable coupling of stealth dark matter to the Higgs boson independent of the
dark matter mass itself. We specialize to , and investigate the
constraints on the model from dark meson decay, electroweak precision
measurements, basic collider limits, and spin-independent direct detection
scattering through Higgs exchange. We exploit our earlier lattice simulations
that determined the composite spectrum as well as the effective Higgs coupling
of stealth dark matter in order to place bounds from direct detection,
excluding constituent fermions with dominantly electroweak-breaking masses. A
lower bound on the dark baryon mass GeV is obtained from the
indirect requirement that the lightest dark meson not be observable at LEP II.
We briefly survey some intriguing properties of stealth dark matter that are
worthy of future study, including: collider studies of dark meson production
and decay; indirect detection signals from annihilation; relic abundance
estimates for both symmetric and asymmetric mechanisms; and direct detection
through electromagnetic polarizability, a detailed study of which will appear
in a companion paper.Comment: 15 pages, 3 figures, citations added, typos fixed, minor
clarification
A Double Sigma Model for Double Field Theory
We define a sigma model with doubled target space and calculate its
background field equations. These coincide with generalised metric equation of
motion of double field theory, thus the double field theory is the effective
field theory for the sigma model.Comment: 26 pages, v1: 37 pages, v2: references added, v3: updated to match
published version - background and detail of calculations substantially
condensed, motivation expanded, refs added, results unchange
Nonabelian (2,0) Tensor Multiplets and 3-algebras
Using 3-algebras we obtain a nonabelian system of equations that furnish a
representation of the (2,0)-supersymmetric tensor multiplet. The on-shell
conditions are quite restrictive so that the system can be reduced to
five-dimensional gauge theory along with six-dimensional abelian (2,0) tensor
multiplets. We briefly discuss possible applications to D4-branes using a
spacelike reduction and M5-branes using a null reduction.Comment: 17 pages, Latex; v2: Typos corrected and references adde
Pathway profiling of a novel SRC inhibitor, AZD0424, in combination with MEK inhibitors
A more comprehensive understanding of how cells respond to drug intervention, the likely immediate signalling responses and how resistance may develop within different microenvironments will help inform treatment regimes. The nonreceptor tyrosine kinase SRC regulates many cellular signalling processes, and pharmacological inhibition has long been a target of cancer drug discovery projects. Here, we describe the in vitro and in vivo characterisation of the small‐molecule SRC inhibitor AZD0424. We show that AZD0424 potently inhibits the phosphorylation of tyrosine‐419 of SRC (IC50 ~ 100 nm) in many cancer cell lines; however, inhibition of cell viability, via a G1 cell cycle arrest, was observed only in a subset of cancer cell lines in the low (on target) micromolar range. We profiled the changes in intracellular pathway signalling in cancer cells following exposure to AZD0424 and other targeted therapies using reverse‐phase protein array (RPPA) analysis. We demonstrate that SRC is activated in response to treatment of KRAS‐mutant colorectal cell lines with MEK inhibitors (trametinib or AZD6244) and that AZD0424 abrogates this. Cell lines treated with trametinib or AZD6244 in combination with AZD0424 had reduced EGFR, FAK and SRC compensatory activation, and cell viability was synergistically inhibited. In vivo, trametinib treatment of mice‐bearing HCT116 tumours increased phosphorylation of SRC on Tyr419, and, when combined with AZD0424, inhibition of tumour growth was greater than with trametinib alone. We also demonstrate that drug‐induced resistance to trametinib is not re‐sensitised by AZD0424 treatment in vitro, likely as a result of multiple compensatory signalling mechanisms; however, inhibition of SRC remains an effective way to block invasion of trametinib‐resistant tumour cells. These data imply that SRC inhibition may offer a useful addition to MEK inhibitor combination strategies
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