757 research outputs found
Rubies : A Novelty Intermezzo Two-Step
https://digitalcommons.library.umaine.edu/mmb-ps/2910/thumbnail.jp
Experimentally implementable criteria revealing substructures of genuine multipartite entanglement
We present a general framework that reveals substructures of genuine
multipartite entanglement. Via simple inequalities it is possible to
discriminate different sets of multipartite qubit states. These inequalities
are beneficial regarding experimental examinations as only local measurements
are required. Furthermore, the number of observables scales favorably with
system size. In exemplary cases we demonstrate the noise resistance and discuss
implementations.Comment: 14 pages, 4 figure
Phonon-Assisted Two-Photon Interference from Remote Quantum Emitters
Photonic quantum technologies are on the verge offinding applications in everyday life with quantum cryptography andquantum simulators on the horizon. Extensive research has beencarried out to identify suitable quantum emitters and single epitaxialquantum dots have emerged as near-optimal sources of bright, on-demand, highly indistinguishable single photons and entangledphoton-pairs. In order to build up quantum networks, it is essentialto interface remote quantum emitters. However, this is still anoutstanding challenge, as the quantum states of dissimilarâartificialatomsâhave to be prepared on-demand with highfidelity and thegenerated photons have to be made indistinguishable in all possibledegrees of freedom. Here, we overcome this major obstacle and show an unprecedented two-photon interference (visibility of 51±5%) from remote strain-tunable GaAs quantum dots emitting on-demand photon-pairs. We achieve this result by exploiting forthefirst time the full potential of a novel phonon-assisted two-photon excitation scheme, which allows for the generation ofhighly indistinguishable (visibility of 71±9%) entangled photon-pairs (fidelity of 90±2%), enables push-button biexciton statepreparation (fidelity of 80±2%) and outperforms conventional resonant two-photon excitation schemes in terms of robustnessagainst environmental decoherence. Our results mark an important milestone for the practical realization of quantum repeatersand complex multiphoton entanglement experiments involving dissimilar artificial atom
Resonant Bend Loss in Leakage Channel Fibers
Leakage channel fibers, designed to suppress higher-order modes, demonstrate
resonant power loss at certain critical radii of curvature. Outside the
resonance, the power recovers to the levels offset by the usual mechanism of
bend-induced loss. Using C-imaging, we experimentally characterize this
anomaly and identify the corresponding physical mechanism as the radiative
decay of the fundamental mode mediated by the resonant coupling to a cladding
mode.Comment: 3 pages, 4 figures, submitted to Optics Letter
On semiclassical calculation of three-point functions in AdS_5 \times T^(1,1)
Recently there has been progress on the computation of two- and three-point
correlation functions with two "heavy" states via semiclassical methods. We
extend this analysis to the case of AdS_5 \times T^(1,1), and examine the
suggested procedure for the case of several simple string solutions. By making
use of AdS/CFT duality, we derive the relevant correlation functions of
operators belonging to the dual gauge theory.Comment: 18 pages, added referenc
Did Cryptic Invasion of North America by Common Reed Change Exposure to Pollen Allergens?
Common reed, Phragmites australis (reed), is a very tall grass that spread greatly to
occupy large areas near many eastern North American cities over the past century. Its
aerially dispersed pollen is known to incite allergic reactions, and possibly asthma, in
some persons, but is not distinguished from that of any other grass in routine pollen
monitoring. We hypothesize that this regional expansion by reed has increased late-season
exposure to grass-pollen allergens in parts of these metropolitan areas. The
information available indicates that reed's geographic location, high abundance, small
pollen size, release of pollen relatively far above ground, substantial pollen
productivity, pollen allergen composition, and late season of pollen release all point to
its potential importance for a large number of persons whose health may be degraded
by grass pollen. If the other common late-flowering grasses in the same area have
larger pollen grains, it may be possible to visually distinguish reed pollen captured by
monitoring devices. If not, ratios of stable isotopes of carbon in the pollen may permit
differentiation. Otherwise, analytical techniques based on molecular differences need
further development in order to estimate local population exposure to allergens from
reed. Some 90 million North Americans may live close enough to large tracts of reed to
be exposed to substantial concentrations of its pollen, so much more attention to this
situation seems warranted. If reed pollen were found to be a health hazard for a
particular metropolitan area, removal of the pollen sources may be more feasible than is
the case for many other species
Conflictos por encuadramiento sindical y/o convencional. El caso Camioneros-Tintoreros
El artĂculo estudia el conflicto por encuadramiento sindical y convencional entre el gremio de Camioneros y el de Tintoreros. La disputa se generĂł en torno a la representaciĂłn de los trabajadores de la categorĂa choferes y ayudantes de carga, en la actividad de Lavaderos Industriales, de Ropa, LimpierĂas y Afines. La investigaciĂłn analizĂł los procesos que llevaron a los trabajadores de la categorĂa disputada a exigir la continuidad de la tutela gremial y convencional bajo la Ăłrbita de Tintoreros. El mĂ©todo utilizado fue el estudio de caso. Los resultados muestran que los conflictos por encuadramiento sindical y/o convencional tensionan la representatividad gremial y la identidad colectiva.This article studies the conflict between Teamsters' and Dry Cleaners' Unions over representation of a particular group of workers. The struggle developed around union representation of drivers and load assistants into the Industrial Laundry sector. Our researcher analyzed the circumstances that led workers in this area to demand their continuity as entitled to Dry Cleaners' Union representation. We used case study as a method of research. The results show that such conflicts over trade union's representation strain both representativeness and collective identity.Fil: Pontoni, Gabriela A. Universidad Nacional de La Matanza; Argentina.Fil: Schimpf, MarĂa BelĂ©n. Universidad Nacional de La Matanza; Argentina
In silico investigation of a KCNQ1 mutation associated with short QT syndrome
Short QT syndrome (SQTS) is a rare condition characterized by abnormally âshortâ QT intervals on the ECG and increased susceptibility to cardiac arrhythmias and sudden death. This simulation study investigated arrhythmia dynamics in multi-scale human ventricle models associated with the SQT2-related V307L KCNQ1 âgain-of-functionâ mutation, which increases slow-delayed rectifier potassium current (IKs). A Markov chain (MC) model recapitulating wild type (WT) and V307L mutant IKs kinetics was incorporated into a model of the human ventricular action potential (AP) for investigation of QT interval changes and arrhythmia substrates. In addition, the degree of simulated IKs inhibition necessary to normalize the QT interval and terminate re-entry in SQT2 conditions was quantified. The developed MC model accurately reproduced AP shortening and reduced effective refractory period associated with altered IKs kinetics in homozygous (V307L) and heterozygous (WT-V307L) mutation conditions, which increased the lifespan and dominant frequency of re-entry in 3D human ventricle models. IKs reductions of 58% and 65% were sufficient to terminate re-entry in WT-V307L and V307L conditions, respectively. This study further substantiates a causal link between the V307L KCNQ1 mutation and pro-arrhythmia in human ventricles, and establishes partial inhibition of IKs as a potential anti-arrhythmic strategy in SQT2
Exploiting Term Hiding to Reduce Run-time Checking Overhead
One of the most attractive features of untyped languages is the flexibility
in term creation and manipulation. However, with such power comes the
responsibility of ensuring the correctness of these operations. A solution is
adding run-time checks to the program via assertions, but this can introduce
overheads that are in many cases impractical. While static analysis can greatly
reduce such overheads, the gains depend strongly on the quality of the
information inferred. Reusable libraries, i.e., library modules that are
pre-compiled independently of the client, pose special challenges in this
context. We propose a technique which takes advantage of module systems which
can hide a selected set of functor symbols to significantly enrich the shape
information that can be inferred for reusable libraries, as well as an improved
run-time checking approach that leverages the proposed mechanisms to achieve
large reductions in overhead, closer to those of static languages, even in the
reusable-library context. While the approach is general and system-independent,
we present it for concreteness in the context of the Ciao assertion language
and combined static/dynamic checking framework. Our method maintains the full
expressiveness of the assertion language in this context. In contrast to other
approaches it does not introduce the need to switch the language to a (static)
type system, which is known to change the semantics in languages like Prolog.
We also study the approach experimentally and evaluate the overhead reduction
achieved in the run-time checks.Comment: 26 pages, 10 figures, 2 tables; an extension of the paper version
accepted to PADL'18 (includes proofs, extra figures and examples omitted due
to space reasons
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