600 research outputs found
Semi-quantum private comparison and its generalization to the key agreement, summation, and anonymous ranking
Semi-quantum protocols construct connections between quantum users and
``classical'' users who can only perform certain ``classical'' operations. In
this paper, we present a new semi-quantum private comparison protocol based on
entangled states and single particles, which does not require pre-shared keys
between the ``classical'' users to guarantee the security of their private
data. By utilizing multi-particle entangled states and single particles, our
protocol can be easily extended to multi-party scenarios to meet the
requirements of multiple ``classical'' users who want to compare their private
data. The security analysis shows that the protocol can effectively prevent
attacks from outside eavesdroppers and adversarial participants. Besides, we
generalize the proposed protocol to other semi-quantum protocols such as
semi-quantum key agreement, semi-quantum summation, and semi-quantum anonymous
ranking protocols. We compare and discuss the proposed protocols with previous
similar protocols. The results show that our protocols satisfy the demands of
their respective counterparts separately. Therefore, our protocols have a wide
range of application scenarios.Comment: 19 pages 5 table
Accelerated Sparse Recovery via Gradient Descent with Nonlinear Conjugate Gradient Momentum
This paper applies an idea of adaptive momentum for the nonlinear conjugate
gradient to accelerate optimization problems in sparse recovery. Specifically,
we consider two types of minimization problems: a (single) differentiable
function and the sum of a non-smooth function and a differentiable function. In
the first case, we adopt a fixed step size to avoid the traditional line search
and establish the convergence analysis of the proposed algorithm for a
quadratic problem. This acceleration is further incorporated with an operator
splitting technique to deal with the non-smooth function in the second case. We
use the convex and the nonconvex functionals as two
case studies to demonstrate the efficiency of the proposed approaches over
traditional methods
A Hybrid Reliable Heuristic Mapping Method Based on Survivable Virtual Networks for Network Virtualization
The reliable mapping of virtual networks is one of the hot issues in network virtualization researches. Unlike the traditional protection mechanisms based on redundancy and recovery mechanisms, we take the solution of the survivable virtual topology routing problem for reference to ensure that the rest of the mapped virtual networks keeps connected under a single node failure condition in the substrate network, which guarantees the completeness of the virtual network and continuity of services. In order to reduce the cost of the substrate network, a hybrid reliable heuristic mapping method based on survivable virtual networks (Hybrid-RHM-SVN) is proposed. In Hybrid-RHM-SVN, we formulate the reliable mapping problem as an integer linear program. Firstly, we calculate the primary-cut set of the virtual network subgraph where the failed node has been removed. Then, we use the ant colony optimization algorithm to achieve the approximate optimal mapping. The links in primary-cut set should select a substrate path that does not pass through the substrate node corresponding to the virtual node that has been removed first. The simulation results show that the acceptance rate of virtual networks, the average revenue of mapping, and the recovery rate of virtual networks are increased compared with the existing reliable mapping algorithms, respectively
Compact Metamaterials Induced Circuits and Functional Devices
In recent years, we have witnessed a rapid expansion of using metamaterials to manipulate light or electromagnetic (EM) wave in a subwavelength scale. Specially, metamaterials have a strict limitation on element dimension from effective medium theory with respect to photonic crystals and other planar structures such as frequency selective surface (FSS). In this chapter, we review our effort in exploring physics and working mechanisms for element miniaturization along with the resulting effects on element EM response. Based on these results, we afford some guidelines on how to design and employ these compact meta-atoms in engineering functional devices with high performances. We found that some specific types of planar fractal or meandered structures are particularly suitable to achieve element miniaturization. In what follows, we review our effort in Section 1 to explore novel theory and hybrid method in designing broadband and dual band planar devices. By using single or double such compact composite right-/left-handed (CRLH) atom, we show that many microwave/RF circuits, i.e., balun, rat-race coupler, power divider and diplexer, can be further reduced while without inducing much transmission loss from two perspectives of lumped and distributed CRLH TLs. In Section 2, we show that a more compact LH atom can be engineered by combining a fractal ring and a meandered thin line. Numerical and experimental results demonstrate that a subwavelength focusing is achieved in terms of smooth outgoing field and higher imaging resolution. Section 3 is devoted to a clocking device from the new concept of superscatterer illusions. To realize the required material parameters, we propose a new mechanism by combining both electric and magnetic particles in a composite meta-atom. Such deep subwavelength particles enable exact manipulation of material parameters and thus facilitate desirable illusion performances of a proof-of-concept sample constructed by 6408 gradually varying meta-atoms. Finally, we summarize our results in the last section
Aqua(2-hydroxy-5-sulfonatobenzoato-κO 1)bis(2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene-κ2 N 7,N 8)zinc(II)
In the title compound, [Zn(C7H4O6S)(C19H12N4)2(H2O)], the ZnII ion is coordinated by two N,N′-bidentate 2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene ligands, one O-monodentate 5-sulfosalicylate dianion and a water molecule. This results in a distorted cis-ZnO2N4 octahedral coordination geometry for the metal ion. In the crystal, molecules are expanded into a three-dimensional supramolecular motif via O—H⋯O, O—H⋯N and N—H⋯(O,S) hydrogen bonds. In addition, π–π stacking interactions between the aromatic rings of the polycyclic ligands consolidate the sturcture [shortest centroid–centroid distance = 3.501 (2) Å]
1-Butyl-3-(1-naphthylmethyl)benzimidazolium hemi{di-μ-iodido-bis[diiodidomercurate(II)]} dimethyl sulfoxide monosolvate
In the title compound, (C22H23N2)[Hg2I6]0.5·(CH3)2SO, the 1-butyl-3-(1-naphthylmethyl)benzimidazolium anion lies across a centre of inversion. The dihedral angle between the benzimidazolium and naphthalene ring systems is 81.9 (3)°. In the crystal structure, π–π stacking interactions are observed between the imidazolium ring and the unsubstituted benzene ring of the naphthalene ring system, with a centroid–centroid separation of 3.510 (5) Å. In the centrosymmetric anion, the Hg(II) atoms are in a distorted tetrahedral coordination. The dimethyl sulfoxide solvent molecule is disordered over two sites with occupancies of 0.615 (9) and 0.385 (9)
Quantum frequency conversion and single-photon detection with lithium niobate nanophotonic chips
In the past few years, the lithium niobate on insulator (LNOI) platform has
revolutionized lithium niobate materials, and a series of quantum photonic
chips based on LNOI have shown unprecedented performances. Quantum frequency
conversion (QFC) photonic chips, which enable quantum state preservation during
frequency tuning, are crucial in quantum technology. In this work, we
demonstrate a low-noise QFC process on an LNOI nanophotonic platform designed
to connect telecom and near-visible bands with sum-frequency generation by
long-wavelength pumping. An internal conversion efficiency of 73% and an
on-chip noise count rate of 900 counts per second (cps) are achieved. Moreover,
the on-chip preservation of quantum statistical properties is verified, showing
that the QFC chip is promising for extensive applications of LNOI integrated
circuits in quantum information. Based on the QFC chip, we construct an
upconversion single-photon detector with the sum-frequency output spectrally
filtered and detected by a silicon single-photon avalanche photodiode,
demonstrating the feasibility of an upconversion single-photon detector on-chip
with a detection efficiency of 8.7% and a noise count rate of 300 cps. The
realization of a low-noise QFC device paves the way for practical chip-scale
QFC-based quantum systems in heterogeneous configurations.Comment: 8pages, 6 figures, 1 tabl
Functional Analysis of the Chemosensory Protein GmolCSP8 From the Oriental Fruit Moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae)
Chemosensory proteins (CSPs) belong to a family of small water-soluble proteins that can selectively bind and transport odorant molecules for olfactory communication in insects. To date, their definite physiological functions in olfaction remain controversial when compared with odorant binding proteins (OBPs). To investigate the functions of CSPs in the oriental fruit moth Grapholita molesta, we determined the tissue expression patterns and binding properties of the CSP, GmolCSP8. The key binding sites of GmolCSP8 with a representative ligand were evaluated using molecular flexible docking, site-directed mutagenesis and ligand-binding experiments. Multiple sequence alignment and phylogenetic analysis showed that GmolCSP8 possesses a typical conserved four cysteines motif and shares high sequence identity with some CSP members of other Lepidopteran insects. GmolCSP8 was predominantly expressed in the wings and antennae of both male and female adults and may be involve in contact chemoreception. Recombinant GmolCSP8 (rGmolCSP8) exhibited specific-binding affinities to small aliphatic alcohols (C4–12) and had the strongest binding affinity to 1-hexanol. The three-dimensional structure of GmolCSP8 was constructed using the structure of sgCSP4 as a template. Site-directed mutagenesis and ligand-binding experiments confirmed that Thr27 is the key binding site in GmolCSP8 for 1-hexanol binding, because this residue can form hydrogen bond with the oxygen atom of the hydroxyl group in 1-hexanol, and Leu30 may play an important role in binding to 1-hexanol. We found that pH significantly affected the binding affinities of rGmolCSP8 to ligand, revealing that ligand-binding and -release by this protein is related to a pH-dependent conformational transition. Based on these results, we infer that GmolCSP8 may participate in the recognition and transportation of 1-hexanol and other small aliphatic alcohols
Neurochemical characterization of pERK-expressing spinal neurons in histamine-induced itch
Date of Acceptance: 08/07/2015 Acknowledgements This work was supported by grants from the Ministry of Science and Technology of China (2012CB966904, 2011CB51005), National Natural Science Foundation of China (31271182, 81200692, 91232724, 81200933, 81101026), Shanghai Natural Science Foundation (12ZR1434300), Key Specialty Construction Project of Pudong Health Bureau of Shanghai (PWZz2013-17), Shenzhen Key Laboratory for Molecular Biology of Neural Development (ZDSY20120617112838879), Fundamental Research Funds for the Central Universities (1500219072) and Sino-UK Higher Education Research Partnership for PhD Studies.Peer reviewedPublisher PD
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