Enhancement of quantum correlations between two particles under decoherence in finite temperature environment

Enhancing the quantum correlations in realistic quantum systems interacting with the environment of finite temperature is an important subject in quantum information processing. In this paper, we use weak measurement and measurement reversal to enhance the quantum correlations in a quantum system consisting of two particles. The transitions of the quantum correlations measured by the local quantum uncertainty of qubit-qubit and qutrit-qutrit quantum systems under generalized amplitude damping channels are investigated. We show that, after the weak measurement and measurement reversal, the joint system shows more robustness against decoherence.Comment: 5 pages, 5 figure

Why does the apparent mass of a coronal mass ejection increase?

Mass is one of the most fundamental parameters characterizing the dynamics of a coronal mass ejection (CME). It has been found that CME apparent mass measured from the brightness enhancement in coronagraph images shows an increasing trend during its evolution in the corona. However, the physics behind it is not clear. Does the apparent mass gain come from the mass outflow from the dimming regions in the low corona, or from the pileup of the solar wind plasma around the CME when it propagates outwards from the Sun? We analyzed the mass evolution of six CME events. Their mass can increase by a factor of 1.6 to 3.2 from 4 to 15 Rs in the field of view (FOV) of the coronagraph on board the Solar Terrestrial Relations Observatory (STEREO). Over the distance about 7 to 15 Rs, where the coronagraph occulting effect can be negligible, the mass can increase by a factor of 1.3 to 1.7. We adopted the `snow-plough' model to calculate the mass contribution of the piled-up solar wind in the height range from about 7 to 15 Rs. For 2/3 of the events, the solar wind pileup is not sufficient to explain the measured mass increase. In the height range from about 7 to 15 Rs, the ratio of the modeled to the measured mass increase is roughly larger than 0.55. Although the ratios are believed to be overestimated, the result gives evidence that the solar wind pileup probably makes a non-negligible contribution to the mass increase. It is not clear yet whether the solar wind pileup is a major contributor to the final mass derived from coronagraph observations. However, our study suggests that the solar wind pileup plays increasingly important role in the mass increase as a CME moves further away from the Sun.Comment: 27 pages, 2 tables, 9 figures, accepted by Ap

Large Magnetoresistance over an Extended Temperature Regime in Monophosphides of Tantalum and Niobium

We report extremely large magnetoresistance (MR) in an extended temperature regime from 1.5 K to 300 K in non-magnetic binary compounds TaP and NbP. TaP exhibits linear MR around $1.8\times 10^4$ at 2 K in a magnetic field of 9 Tesla, which further follows its linearity up to $1.4\times 10^5$ in a magnetic field of 56 Tesla at 1.5 K. At room temperature the MR for TaP and NbP follows a power law of the exponent about $1.5$ with the values larger than $300\%$ in a magnetic field of 9 Tesla. Such large MR in a wide temperature regime is not likely only due to a resonance of the electron-hole balance, but indicates a complicated mechanism underneath.Comment: 13 pages, 4 figures; submitted in May 20, 2015; accepted for publicatio

Role of Inflammatory Factors in Regulation of Osteogenesis in Tissue-Engineered Bone

It was traditionally considered that the inhibition of inflammatory reaction is necessary for osteogenesis, but the latest issue argued inflammation is unavoidable in the process of bone trauma, and physiological inflammatory reaction is essential to achieve bone formation. Tissue-engineered bone graft is not only associated with osteoblast-related cells; the inflammatory reaction is the initial physiological process, mainly with neutrophil infiltration, which secretes MCP-1, IL-8, and other chemokines and further promotes dendritic cells, lymphocytes, and mononuclear macrophages to move in. The activation pathways of macrophages have a direct effect on the outcome of the inflammatory reaction and the healing, which are divided into the classical approach (M1) and the alternative approach (M2). The M1 pathway secretes IL-1 beta, IL-6, TNF-α, and other pro-inflammatory factors, while the M2 pathway secretes arginase, IL-1Ra, IL-4, and other anti-inflammatory cytokines, also with bone-healing-related growth factors, which promote homing of bone mesenchymal stem cells (bMSCs)