Homodyne-based quantum random number generator at 2.9 Gbps secure against quantum side-information

Quantum random number generators promise perfectly unpredictable random numbers. A popular approach to quantum random number generation is homodyne measurements of the vacuum state, the ground state of the electro-magnetic field. Here we experimentally implement such a quantum random number generator, and derive a security proof that considers quantum side-information instead of classical side-information only. Based on the assumptions of Gaussianity and stationarity of noise processes, our security analysis furthermore includes correlations between consecutive measurement outcomes due to finite detection bandwidth, as well as analog-to-digital converter imperfections. We characterize our experimental realization by bounding measured parameters of the stochastic model determining the min-entropy of the system’s measurement outcomes, and we demonstrate a real-time generation rate of 2.9 Gbit/s. Our generator follows a trusted, device-dependent, approach. By treating side-information quantum mechanically an important restriction on adversaries is removed, which usually was reserved to semi-device-independent and device-independent schemes

Assessment of quality of life among Taiwanese patients with visual impairment

This study aims at evaluating the relationship between visual impairment and health-related quality of life (QoL) by identifying factors that affect the EQ-5D index score and Visual Functioning Questionnaire (VFQ) global score, and determining whether the VFQ-25 scores and the European Quality of Life-5 Dimensions (EQ-5D) scores are correlated. Methods: This cross-sectional study comprised 318 patients aged 40 years or more presenting with best corrected visual acuity (BCVA) of 20/40 or worse in the better eye.Patients received comprehensive ophthalmologic examinations, and were administered the National Eye Institute VFQ-25 and the EQ-5D instruments. A higher VFQ-25 score indicates a better QoL and, after conversion of the EQ-5D scores to an index score, a higher EQ-5D index score indicates a better QoL. Results: On multivariate analysis of the EQ-5D index scores, women and those with arthritis were found to have significantly worse QoL, and the EQ-5D index score was increased by every unit increase in BCVA or mean deviation. Multivariate analysis of the VFQ-25 scores revealed that a history of heart disease, arthritis, and eye diseases, such as age-related macular degeneration or diabetic retinopathy, had significant negative effects on patients' QoL, and VFQ-25 global score was decreased by every unit increase in logMAR. According to this analysis, patients' QoL was improved by each unit increase in BCVA or mean deviation. The correlation between the two questionnaires was only weak to moderate. Conclusion: Visual impairment was associated with lower QoL, as assessed by either questionnaire in Taiwanese patients

In Vitro Biocompatibility, Radiopacity, and Physical Property Tests of Nano-Fe3O4 Incorporated Poly-l-lactide Bone Screws

The aim of this study was to fabricate biodegradable poly-l-lactic acid (PLLA) bone screws containing iron oxide (Fe3O4) nanoparticles, which are radiopaque and 3D-printable. The PLLA composites were fabricated by loading 20%, 30%, and 40% Fe3O4 nanoparticles into the PLLA. The physical properties, including elastic modulus, thermal properties, and biocompatibility of the composites were tested. The 20% nano-Fe3O4/PLLA composite was used as the material for fabricating the 3D-printed bone screws. The mechanical performance of the nano-Fe3O4/PLLA bone screws was evaluated by anti-bending and anti-torque strength tests. The tissue response and radiopacity of the nano-Fe3O4/PLLA bone screws were assessed by histologic and CT imaging studies using an animal model. The addition of nano-Fe3O4 increased the crystallization of the PLLA composites. Furthermore, the 20% nano-Fe3O4/PLLA composite exhibited the highest thermal stability compared to the other Fe3O4 proportions. The 3D-printed bone screws using the 20% nano-Fe3O4/PLLA composite provided excellent local tissue response. In addition, the radiopacity of the 20% nano-Fe3O4/PLLA screw was significantly better compared with the neat PLLA screw

Development and Testing of X-Ray Imaging-Enhanced Poly-L-Lactide Bone Screws.

Nanosized iron oxide particles exhibit osteogenic and radiopaque properties. Thus, iron oxide (Fe3O4) nanoparticles were incorporated into a biodegradable polymer (poly-L-lactic acid, PLLA) to fabricate a composite bone screw. This multifunctional, 3D printable bone screw was detectable on X-ray examination. In this study, mechanical tests including three-point bending and ultimate tensile strength were conducted to evaluate the optimal ratio of iron oxide nanoparticles in the PLLA composite. Both injection molding and 3D printing techniques were used to fabricate the PLLA bone screws with and without the iron oxide nanoparticles. The fabricated screws were implanted into the femoral condyles of New Zealand White rabbits. Bone blocks containing the PLLA screws were resected 2 and 4 weeks after surgery. Histologic examination of the surrounding bone and the radiopacity of the iron-oxide-containing PLLA screws were evaluated. Our results indicated that addition of iron oxide nanoparticles at 30% significantly decreased the ultimate tensile stress properties of the PLLA screws. The screws with 20% iron oxide exhibited strong radiopacity compared to the screws fabricated without the iron oxide nanoparticles. Four weeks after surgery, the average bone volume of the iron oxide PLLA composite screws was significantly greater than that of PLLA screws without iron oxide. These findings suggested that biodegradable and X-ray detectable PLLA bone screws can be produced by incorporation of 20% iron oxide nanoparticles. Furthermore, these screws had significantly greater osteogenic capability than the PLLA screws without iron oxide

Experimental verification of quantum discord in continuousvariable states and operational significance of discord consumption

We introduce a simple and efficient technique to verify quantum discord in unknown Gaussian states and certain class of non-Gaussian states. We show that any separation in the peaks of the marginal distributions of one subsystem conditioned on two different outcomes of homodyne measurements performed on the other subsystem indicates correlation between the corresponding quadratures and hence nonzero quantum discord. We also demonstrate that under certain measurement constraints, discord between bipartite systems can be consumed to encode information that can only be accessed by coherent quantum interaction. © 2014 OSA

Images of the four fabricated poly-L-lactide (PLLA) bone screws.

<p>The screws containing 0% (a and c) and 20% (w/w) Fe₃O₄ nanoparticles (b and d). Injection molding (a and b) and 3D printing (c and d) methods were used to produce the screws.</p

A typical example of the histologic image at the screw/bone interface 4 weeks after implanting the screws.

<p>The leached debris of the nano-Fe₃O₄/poly-L-lactide (PLLA) composite was surrounded by newly formed bone and bone cells (black arrow). BC: bone cell; BV: blood vessel; CT: connective tissue; DB: leached debris; MB: mature bone; NB: new bone. Scale bar, 50 μm.</p

Histologic examination of bone tissue at the screw/bone interface 2 weeks after implanting the screws.

<p>Neat poly-L-lactide (PLLA) screws were fabricated by injection molding (a) and 3D printing (c) methods. Screws made of PLLA mixed with 20% Fe₃O₄ nanoparticles fabricated by injection molding (b) and 3D printing (d). New bone (black arrows) was visible between more of the threads and occupied a greater area with the 20% nano-Fe₃O₄/PLLA screw compared to the neat PLLA screw. Scale bar, 1.0 mm.</p