165 research outputs found
Academia’s Role to Drive Change in the Orthotics and Prosthetics Profession
This position paper outlines the important role of academia in shaping the orthotics and prosthetics (O&P) profession and preparing for its future. In the United States, most healthcare professions including O&P are under intense pressure to provide cost effective treatments and quantifiable health outcomes. Pivotal changes are needed in the way O&P services are provided to remain competitive. This will require the integration of new technologies and data driven processes that have the potential to streamline workflows, reduce errors and inform new methods of clinical care and device manufacturing. Academia can lead this change, starting with a restructuring in academic program curricula that will enable the next generation of professionals to cope with multiple demands such as the provision of services for an increasing number of patients by a relatively small workforce of certified practitioners delivering these services at a reduced cost, with the expectation of significant, meaningful, and measurable value. Key curricular changes will require replacing traditional labor-intensive and inefficient fabrication methods with the integration of newer technologies (i.e., digital shape capture, digital modeling/rectification and additive manufacturing). Improving manufacturing efficiencies will allow greater curricular emphasis on clinical training and education - an area that has traditionally been underemphasized. Providing more curricular emphasis on holistic patient care approaches that utilize systematic and evidence-based methods in patient assessment, treatment planning, dosage of O&P technology use, and measurement of patient outcomes is imminent. Strengthening O&P professionals\u27 clinical decision-making skills and decreasing labor-intensive technical fabrication aspects of the curriculum will be critical in moving toward a digital and technology-centric practice model that will enable future practitioners to adapt and survive
Academia’s Role to Drive Change in the Orthotics and Prosthetics Profession
This position paper outlines the important role of academia in shaping the orthotics and prosthetics (O&P) profession and preparing for its future. In the United States, most healthcare professions including O&P are under intense pressure to provide cost effective treatments and quantifiable health outcomes. Pivotal changes are needed in the way O&P services are provided to remain competitive. This will require the integration of new technologies and data driven processes that have the potential to streamline workflows, reduce errors and inform new methods of clinical care and device manufacturing. Academia can lead this change, starting with a restructuring in academic program curricula that will enable the next generation of professionals to cope with multiple demands such as the provision of services for an increasing number of patients by a relatively small workforce of certified practitioners delivering these services at a reduced cost, with the expectation of significant, meaningful, and measurable value. Key curricular changes will require replacing traditional labor-intensive and inefficient fabrication methods with the integration of newer technologies (i.e., digital shape capture, digital modeling/rectification and additive manufacturing). Improving manufacturing efficiencies will allow greater curricular emphasis on clinical training and education - an area that has traditionally been underemphasized. Providing more curricular emphasis on holistic patient care approaches that utilize systematic and evidence-based methods in patient assessment, treatment planning, dosage of O&P technology use, and measurement of patient outcomes is imminent. Strengthening O&P professionals\u27 clinical decision-making skills and decreasing labor-intensive technical fabrication aspects of the curriculum will be critical in moving toward a digital and technology-centric practice model that will enable future practitioners to adapt and survive
Submicron plasticity: yield stress, dislocation avalanches, and velocity distribution
The existence of a well defined yield stress, where a macroscopic piece of
crystal begins to plastically flow, has been one of the basic observations of
materials science. In contrast to macroscopic samples, in micro- and
nanocrystals the strain accumulates in distinct, unpredictable bursts, which
makes controlled plastic forming rather difficult. Here we study by simulation,
in two and three dimensions, plastic deformation of submicron objects under
increasing stress. We show that, while the stress-strain relation of individual
samples exhibits jumps, its average and mean deviation still specify a
well-defined critical stress, which we identify with the jamming-flowing
transition. The statistical background of this phenomenon is analyzed through
the velocity distribution of short dislocation segments, revealing a universal
cubic decay and an appearance of a shoulder due to dislocation avalanches. Our
results can help to understand the jamming-flowing transition exhibited by a
series of various physical systems.Comment: 5 page
Compact parity conserving percolation in one-dimension
Compact directed percolation is known to appear at the endpoint of the
directed percolation critical line of the Domany-Kinzel cellular automaton in
1+1 dimension. Equivalently, such transition occurs at zero temperature in a
magnetic field H, upon changing the sign of H, in the one-dimensional
Glauber-Ising model with well known exponents characterising spin-cluster
growth. We have investigated here numerically these exponents in the
non-equilibrium generalization (NEKIM) of the Glauber model in the vicinity of
the parity-conserving phase transition point of the kinks. Critical
fluctuations on the level of kinks are found to affect drastically the
characteristic exponents of spreading of spins while the hyperscaling relation
holds in its form appropriate for compact clusters.Comment: 7 pages, 7 figures embedded in the latex, final form before J.Phys.A
publicatio
Bound entangled singlet-like states for quantum metrology
Bipartite entangled quantum states with a positive partial transpose (PPT),
i.e., PPT entangled states, are usually considered very weakly entangled. Since
no pure entanglement can be distilled from them, they are also called bound
entangled. In this paper we present two classes of ()-dimensional
PPT entangled states for any which outperform all separable states in
metrology significantly. We present strong evidence that our states provide the
maximal metrological gain achievable by PPT states for a given system size.
When the dimension goes to infinity, the metrological gain of these states
becomes maximal and equals the metrological gain of a pair of maximally
entangled qubits. Thus, we argue that our states could be called "PPT
singlets."Comment: 17 pages including 3 figures, revtex4.2; v2: presentation improved,
some further results added, links to MATLAB programs generating the bound
entangled states added; v3: published versio
Crossovers from parity conserving to directed percolation universality
The crossover behavior of various models exhibiting phase transition to
absorbing phase with parity conserving class has been investigated by numerical
simulations and cluster mean-field method. In case of models exhibiting Z_2
symmetric absorbing phases (the NEKIMCA and Grassberger's A stochastic cellular
automaton) the introduction of an external symmetry breaking field causes a
crossover to kink parity conserving models characterized by dynamical scaling
of the directed percolation (DP) and the crossover exponent: 1/\phi ~ 0.53(2).
In case an even offspringed branching and annihilating random walk model (dual
to NEKIMCA) the introduction of spontaneous particle decay destroys the parity
conservation and results in a crossover to the DP class characterized by the
crossover exponent: 1/\phi\simeq 0.205(5). The two different kinds of crossover
operators can't be mapped onto each other and the resulting models show a
diversity within the DP universality class in one dimension. These
'sub-classes' differ in cluster scaling exponents.Comment: 6 pages, 6 figures, accepted version in PR
Uncertainty relations with the variance and the quantum Fisher information based on convex decompositions of density matrices
We present several inequalities related to the Robertson-Schr\"odinger
uncertainty relation. In all these inequalities, we consider a decomposition of
the density matrix into a mixture of states, and use the fact that the
Robertson-Schr\"odinger uncertainty relation is valid for all these components.
By considering a convex roof of the bound, we obtain an alternative derivation
of the relation in Fr\"owis et al. [Phys. Rev. A 92, 012102 (2015)], and we can
also list a number of conditions that are needed to saturate the relation. We
present a formulation of the Cram\'er-Rao bound involving the convex roof of
the variance. By considering a concave roof of the bound in the
Robertson-Schr\"odinger uncertainty relation over decompositions to mixed
states, we obtain an improvement of the Robertson-Schr\"odinger uncertainty
relation. We consider similar techniques for uncertainty relations with three
variances. Finally, we present further uncertainty relations that provide lower
bounds on the metrological usefulness of bipartite quantum states based on the
variances of the canonical position and momentum operators for two-mode
continuous variable systems. We show that the violation of well-known
entanglement conditions in these systems discussed in Duan et al., [Phys. Rev.
Lett. 84, 2722 (2000)] and Simon [Phys. Rev. Lett. 84, 2726 (2000)] implies
that the state is more useful metrologically than certain relevant subsets of
separable states. We present similar results concerning entanglement conditions
with angular momentum operators for spin systems.Comment: 17 pages including 3 figures, revtex4.2. See also the related work S.
H. Chiew and M. Gessner, Phys. Rev. Research 4, 013076 (2022
Entanglement and Extreme Spin Squeezing for a Fluctuating Number of Indistinguishable Particles
We extend the criteria for -particle entanglement from the spin squeezing
parameter presented in [A.S. S{\o}rensen and K. M{\o}lmer, Phys. Rev. Lett.
{\bf 86}, 4431 (2001)] to systems with a fluctating number of particles. We
also discuss how other spin squeezing inequalities can be generalized to this
situation. Further, we give an operational meaning to the bounds for cases
where the individual particles cannot be addressed. As a by-product, this
allows us to show that in spin squeezing experiments with cold gases the
particles are typically distinguishable in practise. Our results justify the
application of the S{\o}rensen-M{\o}lmer bounds in recent experiments on spin
squeezing in Bose-Einstein condensates
Correlated Initial Conditions in Directed Percolation
We investigate the influence of correlated initial conditions on the temporal
evolution of a (d+1)-dimensional critical directed percolation process.
Generating initial states with correlations ~r^(sigma-d) we
observe that the density of active sites in Monte-Carlo simulations evolves as
rho(t)~t^kappa. The exponent kappa depends continuously on sigma and varies in
the range -beta/nu_{||}<=kappa<=eta. Our numerical results are confirmed by an
exact field-theoretical renormalization group calculation.Comment: 10 pages, RevTeX, including 5 encapsulated postscript figure
HAT-P-5b: A Jupiter-like hot Jupiter Transiting a Bright Star
We report the discovery of a planet transiting a moderately bright (V =
12.00) G star, with an orbital period of 2.788491 +/-0.000025 days. From the
transit light curve we determine that the radius of the planet is Rp = 1.257
+/- 0.053 RJup. HAT-P-5b has a mass of Mp = 1.06 +/- 0.11 MJup, similar to the
average mass of previously-known transiting exoplanets, and a density of rho =
0.66 +/- 0.11 g cm^-3 . We find that the center of transit is Tc =
2,454,241.77663 +/- 0.00022 (HJD), and the total transit duration is 0.1217 +/-
0.0012 days.Comment: 5 pages, submitted to APJ
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