In this paper, we experimentally realized a gigabit-class indoor visible light communication system using commercially available RGB White LED and exploiting an optimized DMT modulation. We achieved ...data rate of 1.5 Gbit/s with single channel and 3.4 Gbit/s by implementing WDM transmission at standard illumination levels. In both experiments, the resulting bit error ratios were below the FEC limit. To the best of our knowledge, these values are the highest ever achieved in VLC systems.
Light-emitting diodes (LEDs), which will be increasingly used in lighting technology, will also allow for distribution of broadband optical wireless signals. Visible-light communication (VLC) using ...white LEDs offers several advantages over the RF-based wireless systems, i.e., license-free spectrum, low power consumption, and higher privacy. Mostly, optical wireless can provide much higher data rates. In this paper, we demonstrate a VLC system based on a white LED for indoor broadband wireless access. After investigating the nonlinear effects of the LED and the power amplifier, a data rate of 1 Gb/s has been achieved at the standard illuminance level, by using an optimized discrete multitone modulation technique and adaptive bit- and power-loading algorithms. The bit-error ratio of the received data was 1.5\cdot 10^{-3} , which is within the limit of common forward error correction (FEC) coding. These results twice the highest capacity that had been previously obtained.
Skeletal muscle fibres form by fusion of mesoderm progenitors called myoblasts. After birth, muscle fibres do not increase in number but continue to grow in size because of fusion of satellite cells, ...the postnatal myogenic cells, responsible for muscle growth and regeneration. Numerous studies suggest that, on transplantation, non-myogenic cells also may contribute to muscle regeneration. However, there is currently no evidence that such a contribution represents a natural developmental option of these non-myogenic cells, rather than a consequence of experimental manipulation resulting in cell fusion. Here we show that pericytes, transgenically labelled with an inducible Alkaline Phosphatase CreERT2, but not endothelial cells, fuse with developing myofibres and enter the satellite cell compartment during unperturbed postnatal development. This contribution increases significantly during acute injury or in chronically regenerating dystrophic muscle. These data show that pericytes, resident in small vessels of skeletal muscle, contribute to its growth and regeneration during postnatal life.
We study the axial U(1) symmetry at a finite temperature in two-flavor lattice QCD. Employing the Möbius domain-wall fermions, we generate gauge configurations slightly above the critical temperature ...Tc with different lattice sizes L=2–4 fm. Our action allows frequent topology tunneling while keeping good chiral symmetry close enough to that of overlap fermions. This allows us to recover full chiral symmetry by an overlap/domain-wall reweighting. Above the phase transition, a strong suppression of the low-lying modes is observed in both overlap and domain-wall Dirac spectra. We, however, find a sizable violation of the Ginsparg-Wilson relation in the Möbius domain-wall Dirac eigenmodes, which dominates the signals of the axial U(1) symmetry breaking near the chiral limit. We also find that the use of the overlap fermion only in the valence sector is dangerous since it suffers from the artifacts due to partial quenching. Reweighting the Möbius domain-wall fermion determinant to that of the overlap fermion, we observe the axial U(1) breaking to vanish in the chiral limit, which is stable against the changes of the lattice volume and lattice spacing.
We analytically derive the outage probability (OP) estimation of a ground-to-satellite pre-amplified free-space optical (FSO) link. Our derivations analysis, for the first time, takes into account ...all the probabilistic impairments, i.e., atmospheric turbulence, beam wander and pointing errors (PEs). Novel, analytical closed-form expressions are extracted for the probability density function (PDF) and the cumulative distribution function (CDF) of the optical signal-to-noise ratio (OSNR) at the receiver pre-amplifier output. Furthermore, we conduct the asymptotic outage analysis in the high-OSNR regime, which provides insightful results for the uplink amplified FSO systems. Numerical OP results are presented for the case of a ground FSO link to a Geostationary Earth orbit (GEO) satellite under various turbulence conditions and misalignment scenarios. Finally, the whole outage analysis is verified by Monte Carlo simulations.
Background and purpose
Depressed mood is a common psychiatric problem associated with Parkinson's disease (PD), and studies have suggested a benefit of rasagiline treatment.
Methods
ACCORDO (see the ...) was a 12‐week, double‐blind, placebo‐controlled trial to evaluate the effects of rasagiline 1 mg/day on depressive symptoms and cognition in non‐demented PD patients with depressive symptoms. The primary efficacy variable was the change from baseline to week 12 in depressive symptoms measured by the Beck Depression Inventory (BDI‐IA) total score. Secondary outcomes included change from baseline to week 12 in cognitive function as assessed by a comprehensive neuropsychological battery; Parkinson's disease quality of life questionnaire (PDQ‐39) scores; Apathy Scale scores; and Unified Parkinson's Disease Rating Scale (UPDRS) subscores.
Results
One hundred and twenty‐three patients were randomized. At week 12 there was no significant difference between groups for the reduction in total BDI‐IA score (primary efficacy variable). However, analysis at week 4 did show a significant difference in favour of rasagiline (marginal means difference ± SE: rasagiline −5.46 ± 0.73 vs. placebo −3.22 ± 0.67; P = 0.026). There were no significant differences between groups on any cognitive test. Rasagiline significantly improved UPDRS Parts I (P = 0.03) and II (P = 0.003) scores versus placebo at week 12. Post hoc analyses showed the statistical superiority of rasagiline versus placebo in the UPDRS Part I depression item (P = 0.04) and PDQ‐39 mobility (P = 0.007) and cognition domains (P = 0.026).
Conclusions
Treatment with rasagiline did not have significant effects versus placebo on depressive symptoms or cognition in PD patients with moderate depressive symptoms. Although limited by lack of correction for multiple comparisons, post hoc analyses signalled some improvement in patient‐rated cognitive and depression outcomes.
We investigate the axial U ( 1 ) anomaly of two-flavor QCD at temperatures 190–330 MeV. In order to preserve precise chiral symmetry on the lattice, we employ the Möbius domain-wall fermion action as ...well as overlap fermion action implemented with a stochastic reweighting technique. Compared to our previous studies, we reduce the lattice spacing to 0.07 fm, simulate larger multiple volumes to estimate finite size effect, and take more than four quark mass points, including one below physical point to investigate the chiral limit. We measure the topological susceptibility, axial U ( 1 ) susceptibility, and examine the degeneracy of U ( 1 ) partners in meson/baryon correlators. All the data above the critical temperature indicate that the axial U ( 1 ) violation is consistent with zero within statistical errors. The quark mass dependence suggests disappearance of the U ( 1 ) anomaly at a rate comparable to that of the S U ( 2 ) L × S U ( 2 ) R symmetry breaking.
Based on a complete set of J = 0 and J = 1 spatial isovector correlation functions calculated with NF = 2 domain wall fermions we identify an intermediate temperature regime of T~220–500 MeV ...(1.2Tc–2.8Tc), where chiral symmetry is restored but the correlators are not yet compatible with a simple free quark behavior. More specifically, in the temperature range T~220–500 MeV we identify a multiplet structure of spatial correlators that suggests emergent SU(2)CS and SU(4) symmetries, which are not symmetries of the free Dirac action. The symmetry breaking effects in this temperature range are less than 5%. Our results indicate that at these temperatures the chromomagnetic interaction is suppressed and the elementary degrees of freedom are chirally symmetric quarks bound into color-singlet objects by the chromoelectric component of the gluon field. At temperatures between 500 and 660 MeV the emergent SU(2)CS and SU(4) symmetries disappear and one observes a smooth transition to the regime above T~1 GeV where only chiral symmetries survive, which are finally compatible with quasifree quarks.
We design and experimentally demonstrate a 10 Gbit/s optical wireless communication (OWC) system that can be quickly deployed and effectively used in data centers (DCs) networks. It is realized by ...means of commercial off-the-shelf (COTS) components, it does not need active alignment, and its 8-mm tolerance allows for simple passive alignment. We successfully tested the system from 1.5 to 3 m link distance with a target bit error ratio (BER) of 10 -9 . This allows the realization of an array of transceivers to further increase the capacity. Finally, the system power consumption (10 pJ/bit) is much lower than its alternatives. These results demonstrate that the proposed OWC system can be a viable solution for future DC networks.
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