3,296 research outputs found
Through-Transmission Impedance Measurements on Moving Metallic Sheets
Eddy current measurement of electrical resistivity provides a method of sensing temperature during metals processing, thus offering a method of feedback control [1,2]. This method assumes a known resistivity-temperature relation for the alloy being processed. However, in many common processing configurations a measurement of the impedance of the coil system can depend on the velocity of the product being tested. In the through-transmission (abbreviated thru-trans) configuration for monitoring moving metallic sheets, the component of the exciting magnetic field normal to the sheet induces an electric field in the sheet transverse to the direction of the velocity. This modifies the induced current distribution and thus changes the shielding of the field at the receiver coil relative to the condition for the static case. This effect is significant even in the case of extruded aluminum moving at 150 ft/min. In high speed rolling, at 1000 ft/min or greater, the effect of velocity is even more significant
R-spondin1 synergizes with Wnt3A in inducing osteoblast differentiation and osteoprotegerin expression
AbstractR-spondins are a new group of Wnt/β-catenin signaling agonists, however, the role of these proteins in bone remains unclear. We reported herein that R-sponin1 (Rspo1) acted synergistically with Wnt3A to activate Wnt/β-catenin signaling in the uncommitted mesenchymal C2C12 cells. Furthermore, we found that Rspo1 at concentrations as low as 10ng/ml synergized strongly with Wnt3A to induce C2C12 osteoblastic differentiation and osteoprotegerin expression. These events were blocked by Wnt/β-catenin signaling antagonist Dickkopf-1. Finally, we demonstrated that Rspo1 synergized with Wnt3A to induce primary mouse osteoblast differentiation. Together, these findings suggest that Rpos1 may play an important role in bone remodeling
Interpreting a 1 fb^-1 ATLAS Search in the Minimal Anomaly Mediated Supersymmetry Breaking Model
Recent LHC data significantly extend the exclusion limits for supersymmetric
particles, particularly in the jets plus missing transverse momentum channels.
The most recent such data have so far been interpreted by the experiment in
only two different supersymmetry breaking models: the constrained minimal
supersymmetric standard model (CMSSM) and a simplified model with only squarks
and gluinos and massless neutralinos. We compare kinematical distributions of
supersymmetric signal events predicted by the CMSSM and anomaly mediated
supersymmetry breaking (mAMSB) before calculating exclusion limits in mAMSB. We
obtain a lower limit of 900 GeV on squark and gluino masses at the 95%
confidence level for the equal mass limit, tan(beta)=10 and mu>0.Comment: 18 pages, 11 figure
Assays to monitor aggrephagy in Drosophila brain
Accumulation of ubiquitinated protein aggregates is a hallmark of most ageingrelated neurodegenerative disorders. Autophagy has been found to be involved in the selective clearance of these protein aggregates, and this process is called aggrephagy. Here we provide two protocols for the investigation of protein aggregation and their removal by autophagy using western blotting and immunofluorescence techniques in Drosophila brain. Investigating the role of aggrephagy at the cellular and organismal level is important for the development of therapeutic interventions against ageing-related diseases
On stability of discretizations of the Helmholtz equation (extended version)
We review the stability properties of several discretizations of the
Helmholtz equation at large wavenumbers. For a model problem in a polygon, a
complete -explicit stability (including -explicit stability of the
continuous problem) and convergence theory for high order finite element
methods is developed. In particular, quasi-optimality is shown for a fixed
number of degrees of freedom per wavelength if the mesh size and the
approximation order are selected such that is sufficiently small and
, and, additionally, appropriate mesh refinement is used near
the vertices. We also review the stability properties of two classes of
numerical schemes that use piecewise solutions of the homogeneous Helmholtz
equation, namely, Least Squares methods and Discontinuous Galerkin (DG)
methods. The latter includes the Ultra Weak Variational Formulation
Some Aspects of Multifractal analysis
The aim of this survey is to present some aspects of multifractal analysis
around the recently developed subject of multiple ergodic averages. Related
topics include dimensions of measures, oriented walks, Riesz products etc
Is Our Universe Natural?
It goes without saying that we are stuck with the universe we have.
Nevertheless, we would like to go beyond simply describing our observed
universe, and try to understand why it is that way rather than some other way.
Physicists and cosmologists have been exploring increasingly ambitious ideas
that attempt to explain why certain features of our universe aren't as
surprising as they might first appear.Comment: Invited review for Nature, 11 page
Spawning rings of exceptional points out of Dirac cones
The Dirac cone underlies many unique electronic properties of graphene and
topological insulators, and its band structure--two conical bands touching at a
single point--has also been realized for photons in waveguide arrays, atoms in
optical lattices, and through accidental degeneracy. Deformations of the Dirac
cone often reveal intriguing properties; an example is the quantum Hall effect,
where a constant magnetic field breaks the Dirac cone into isolated Landau
levels. A seemingly unrelated phenomenon is the exceptional point, also known
as the parity-time symmetry breaking point, where two resonances coincide in
both their positions and widths. Exceptional points lead to counter-intuitive
phenomena such as loss-induced transparency, unidirectional transmission or
reflection, and lasers with reversed pump dependence or single-mode operation.
These two fields of research are in fact connected: here we discover the
ability of a Dirac cone to evolve into a ring of exceptional points, which we
call an "exceptional ring." We experimentally demonstrate this concept in a
photonic crystal slab. Angle-resolved reflection measurements of the photonic
crystal slab reveal that the peaks of reflectivity follow the conical band
structure of a Dirac cone from accidental degeneracy, whereas the complex
eigenvalues of the system are deformed into a two-dimensional flat band
enclosed by an exceptional ring. This deformation arises from the dissimilar
radiation rates of dipole and quadrupole resonances, which play a role
analogous to the loss and gain in parity-time symmetric systems. Our results
indicate that the radiation that exists in any open system can fundamentally
alter its physical properties in ways previously expected only in the presence
of material loss and gain
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