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Hyperentangled Bell states analysis (HBSA) is an essential building block for certain hyper-parallel quantum information processing. We propose a complete and deterministic HBSA scheme encoded in spatial and polarization degrees of freedom (DOFs) of two-photon system assisted by a fixed frequency-based entanglement and a time interval DOF. The parity information the spatial-based and polarization-based hyper-entanglement can be distinguished by the distinct time intervals of the photon pairs, and the phase information can be distinguished by the detection signature. Compared with previous schemes, the number of the auxiliary entanglements is reduced from two to one by introducing time interval DOF. Moreover, the additional frequency and time interval DOFs suffer less from the collective channel noise., Comment: 8 pages, 1 figure, and 1 table

We present an error-detected hyperparallel Toffoli (hyper-Toffoli) gate for a three-photon system based on the interface between polarized photon and cavity-nitrogen-vacancy(NV) center system. This hyper-Toffoli gate can be used to perform double Toffoli gate operations simultaneously on both the polarization and spatial-mode degrees of freedom (DoFs) of a three-photon system with a low decoherence, shorten operation time, and less quantum resources required, in compared with those on two independent three-photon systems in one DoF only. As the imperfect cavity-NV-center interactions are transformed into the detectable failures rather than infidelity based on the heralding mechanism of detectors, a near-unit fidelity of the quantum hyper-Toffoli gate can be implemented. By recycling the procedures, the efficiency of our protocol for the hyper-Toffoli gate is improved further. Meanwhile, the evaluation of gate performance with achieved experiment parameters shows that it is feasible with current experimental technology and provides a promising building block for quantum compute.

We present a faithful and efficient hyperentanglement purification protocol (hyper-EPP) for nonlocal two-photon systems in spatial-polarization-time-bin hyperentangled Bell states. As the single-photon detectors can detect and herald the undesirable properties caused by side leakage and finite coupling strength, the parity-check gates and swap gates of our hyper-EPP in the spatial, polarization and time-bin mode degrees of freedom (DoFs) work faithfully. The qubit-flip errors in photon systems in three DoFs can be corrected effectively with the faithful parity-check gates and the photon pairs can be reused to distill high-fidelity ones by introducing the faithful swap gates, which greatly increases the efficiency of our hyper-EPP. Further, the maximal hyperentanglement can be obtained in principle by operating multiple rounds of the hyper-EPP.

B cell lymphoma-2-like 2 (BCL2L2), an important regulator of apoptosis, plays vital roles in several physiological processes, as revealed by studies in humans and mice. However, reports on pig BCL2L2 are few, and the encoding gene has not been identified experimentally. This study was designed to clone the porcine BCL2L2 gene and its alternative splicing (AS) transcripts using molecular biological techniques and to analyze the regulatory mechanisms underlying transcription and translation. The BCL2L2 cDNA (V1) was 807 bp in length and encoded a polypeptide of 193 aa containing four BCL-2 homology domains. A total of nine AS transcripts were obtained, among which V2 and V3 differed from V1 in the 5' untranslated region (UTR). The core promoter was mapped to a range of -1102 to -759 bp (the first nucleotide of the start codon was designated as +1). There were several functional cis-elements, including one SP1 and two C/EBPα binding sites at around -759 bp. AS in the 5' UTR is involved in the regulation of gene expression, as revealed by dual-luciferase reporter and western blot analysis, and the secondary structure of the 5' UTRs may be the reason for the differential expression of V1-3. At the same time, an upstream open reading frame (ORF) existed in each of the three 5' UTRs, was found to repress the expression of the main ORF. Additionally, the roles of porcine BCL2L2 in cell proliferation and apoptosis were preliminarily analyzed. The results will contribute to further characterizing the role of BCL2L2.

Hyperentangled states can outperform their classical counterparts on solving certain tasks. Here we present a simplified scheme for completely distinguishing two-photon hyperentangled Bell states in polarization, spatial, and time-bin degrees of freedom (DOFs). Unity fidelity can be achieved in principle without strong couple limitation between photon and quantum dot (QD), and the incomplete and imperfect QD-cavity interactions are prevented by single-photon detectors. In addition, auxiliary photons or DOFs are not required in our scheme. The necessary linear optical elements are fewer than the parity-check-based one., 3 figures, 1 table

We propose three schemes to generate polarization W-states of size $$n+m$$ , $$n+m+t$$ , and $$n+m+t+z$$ without qubit loss, i.e., large-sized $$W_{n+m}$$ ( $$W_{n+m+t}$$ and $$W_{n+m+t+z}$$ ) is generated from one $$W_n$$ and one $$W_m$$ (one $$W_n$$ , one $$W_m$$ , and one $$W_t$$ , and one $$W_n$$ , one $$W_m$$ , one $$W_t$$ , and one $$W_z$$ ). The qubit-loss-free fusion mechanism increases the size of the fusion W states essentially, i.e., reduces the fusion steps, which makes the implementations of the schemes possible within current technology. Ancillary photons, controlled-NOT, Toffoli, Fredkin, and partial-SWAP gates are not required in our schemes. In addition, the number of the coherence states is reduced from 3 to 2, and path couplers are not employed. There is no complete failure output, and all garbage states are recyclable in the $$W_{n+m}$$ fusion scheme.

We present a self-error-rejecting multipartite entanglement purification protocol (MEPP) for N-electron-spin entangled states, resorting to the single-side cavity-spin-coupling system. Our MEPP has a high efficiency containing two steps. One is to obtain high-fidelity N-electron-spin entangled systems with error-heralded parity-check devices (PCDs) in the same parity-mode outcome of three electron-spin pairs, as well as M-electron-spin entangled subsystems (2 ≤ M < N) in the different parity-mode outcomes of those. The other is to regain the N-electron-spin entangled systems from M-electron-spin entangled states utilizing entanglement link. Moreover, the quantum circuits of PCDs make our MEPP works faithfully, due to the practical photon-scattering deviations from the finite side leakage of the microcavity, and the limited coupling between a quantum dot and a cavity mode, converted into a failed detection in a heralded way.

We present two nonlocal entanglement concentration protocols (ECPs) to distill a subset of N-photon systems in a Greenberger-Horne-Zeilinger (GHZ) state or a W state from a set of photon systems in a partially entangled GHZ-like pure state or a less-entangled W-like state with known parameter, respectively. Our ECPs have some advantages. First, our ECPs work in a heralded way with linear-optical elements only, without the postselection based on nonlinear optics, far different from the previous ECPs. Second, they require only a copy of the less-entangled photon system in each round of the entanglement concentration process, not two copies, which decreases the difficulty of their implementation in experiment largely. Third, our ECPs avoid checking the photon number in the output modes of linear-optical elements with the sophisticated single-photon detectors. Moreover, all parties can operate the process for concentration simultaneously and independently, which leads to flexible operations and improves the performance greatly in experiment. These advantages make our ECPs useful in practical applications in long-distance quantum communication network.

We present a refined entanglement concentration protocol (ECP) for an arbitrary unknown less-entangled four-electron-spin cluster state by exploring the optical selection rules derived from the quantum-dot spins in one-sided optical microcavities. In our ECP, the parties obtain not only the four-electron-spin systems in the partial entanglement with two unknown parameters, but also the less-entangled two-electron-spin systems in the first step. Utilizing the above preserved systems as the resource for the second step of our ECP, the parties can obtain a standard cluster state by keeping the robust odd-parity instances with two parity-check gates. Meanwhile, the systems in the rest three instances can be used as the resource in the next round of our ECP. The success probability of our ECP is largely increased by iteration of the ECP process. Moreover, all the coefficients of our ECP are unknown for the parties without assistance of extra single electron-spin, so our ECP maybe has good applications in quantum communication network in the future.

Analysis from three aspects of social efficiency, economic efficiency and ecological efficiency of land use efficiency in Xi'an City 2000-2010; using coordination degree model, to calculate the overall coordination degree of social efficie-ncy, economic efficiency and ecological efficiency in Xi'an City. The results show that land-using overall efficiency index in Xi'an has a trend to upward , especially after 2009, coordination degree grows better , tends to a coordin-ationated development.

Entanglement concentration protocol (ECP) is used to extract the maximally entangled states from less entangled pure states. Here we present a general hyperconcentration protocol for two-photon systems in partially hyperentangled Bell states that decay with the interrelation between the time-bin and the polarization degrees of freedom (DOFs), resorting to an input-output process with respect to diamond nitrogen-vacancy centers coupled to resonators. We show that the resource can be utilized sufficiently and the success probability is largely improved by iteration of the hyper-ECP process. Besides, our hyper-ECP can be directly extended to concentrate nonlocal partially hyperentangled N-photon Greenberger-Horne-Zeilinger states, and the success probability remains unchanged with the growth of the number of photons. Moreover, the time-bin entanglement is a useful DOF and it only requires one path for transmission, which means it not only economizes on a large amount of quantum resources but also relaxes from the path-length dispersion in long-distance quantum communication.

As the daughter of modern wireless communication technology & computer network technology, Wireless Local Area Network(WLAN) is being used widely in many areas. It is well known that WLAN has the advantages such as simple network configuration, high transmission rate, good extensibility and mobility, and convenience to carry, etc. However, its security mechanism is not perfect to guarantee its security because of some design flaws in safety precautions. The application of AES in WLAN improves its data confidentiality. The work presented in this paper focuses on present AES encryption algorithm security problem and optimization of its S Box. The improved algorithm this paper put forward in WLAN, is proved to be efficient.

The largemouth bass belongs to the family Centrarchidae, which includes two subspecies: the northern subspecies, Micropterus salmoides salmoides, and the Florida subspecies, Micropterus salmoides floridanus. In this study, the complete mitochondrial genomes of the two subspecies were sequenced, and their genetic differences were identified. The mitogenomes of M. s. salmoides and M. s. floridanus are 16,486 and 16,479 bp in length, respectively. The two subspecies consisted of 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA), which are typical for vertebrate mtDNA. Phylogenetic analysis provided statistical support for the monophyly of the family Centrarchidae. Comparison of the two subspecies' mitogenomes revealed a relatively high number (450) of single nucleotide polymorphisms (SNPs) in protein-coding genes. We characterized SNPs in the partial cytochrome c oxidase subunit 1 gene of different individuals from three cultured populations, one wild northern subspecies population, and one wild Florida subspecies population. Twenty-eight SNPs were fixed with alternative nucleotides in the two subspecies, which could be used for differentiating them. Based on this gene, phylogenetic tree and genetic distance analyses supported that cultured largemouth bass in China belongs to the northern subspecies.

The prevenient mechanical research on U type steel support focuses on two dimensional analysis in the installing plan. Interested in the buckling failure of U type steel support’s pinnas in one coal mine of Huainan Group, the authors build three dimensional models to stimulating 25U and 29U support. The appealing simulation results verify ANSYS’s 3-D computational capabilities about complicated section support. The main objective of their investigation has been to obtain some knowledge of the mechanism, stress distribution, and load magnitude in the support’s deforming. Further, the deviating longitudinal load play an accelerating deformation role on its distorting, which should be paied more attention to cross-section optimization, design of support parameters, and installing way of steel lacing.

We present a systematic entanglement concentration protocol (ECP) for an arbitrary unknown less-entangled three-photon W state, resorting to the optical property of the quantum-dot spins inside one-sided optical microcavities. In our ECP, the parties obtain not only some three-photon systems in the partially entangled with two unknown parameters when one of the parties picks up the robust odd-parity instance with the parity-check gate (PCG) on his two photons, but also some entangled two-photon systems by keeping the even-parity instance in the first step. By exploiting the above three-photon and two-photon systems with the same parameters as the resource for the second step of our ECP, the parties can obtain a standard three-photon W state by keeping the robust odd-parity instance. Meanwhile, the systems in the even-parity instance can be used as the resource in the next round of our ECP. The success probability of our ECP is largely increased by iteration of the ECP process. As it does require that all the coefficients are unknown for the parties, our ECP maybe have good applications in quantum communication network in future., Comment: 8 pages, 6 figures

Hyperentanglement is a promising resource in quantum information processing, especially for increasing the channel capacity of long-distance quantum communication. Hyperentanglement purification is an important method to obtain high-fidelity nonlocal hyperentangled states from mixed hyperentangled states in a long-distance quantum communication process with noisy channels. Here, we present a two-step hyperentanglement purification protocol for nonlocal mixed hyperentangled states with polarization bit-flip errors and spatial-mode phase-flip errors, resorting to polarization-spatial phase-check quantum nondemolition detectors and the quantum-state-joining method (QSJM). With QSJM, the protocol can preserve the states that are discarded in the previous hyperentanglement purification protocols. It has the advantage of a high efficiency, and it is useful for improving the entanglement of photon systems with several degrees of freedom in long-distance high-capacity quantum communication., 16 pages, 8 figures

Hyperentanglement, defined as the entanglement in several degrees of freedom (DOFs) of a quantum system, has attracted much attention recently. Here we investigate the possibility of concentrating the two-photon four-qubit systems in partially hyperentangled states in both the spatial mode and the polarization DOFs with linear optics. We first introduce our parameter-splitting method to concentrate the systems in the partially hyperentangled states with known parameters, including partially hyperentangled Bell states and cluster states. Subsequently, we present another two nonlocal hyperentanglement concentration protocols (hyper-ECPs) for the systems in partially hyperentangled unknown states, resorting to the Schmidt projection method. It will be shown that our parameter-splitting method is very efficient for the concentration of the quantum systems in partially entangled states with known parameters, resorting to linear-optical elements only. All these four hyper-ECPs are feasible with current technology and they may be useful in long-distance quantum communication based on hyperentanglement as they require only linear optical elements., Comment: 13 pages, 10 figures

We propose a nonlocal entanglement concentration protocol (ECP) for $N$-photon systems in a partially entangled W state, resorting to some ancillary single photons and the parity-check measurement based on cross-Kerr nonlinearity. One party in quantum communication first performs a parity-check measurement on her photon in an $N$-photon system and an ancillary photon, and then she picks up the even-parity instance for obtaining the standard W state. When she obtains an odd-parity instance, the system is in a less-entanglement state and it is the resource in the next round of entanglement concentration. By iterating the entanglement concentration process several times, the present ECP has the total success probability approaching to the limit in theory. The present ECP has the advantage of a high success probability. Moreover, the present ECP requires only the $N$-photon system itself and some ancillary single photons, not two copies of the systems, which decreases the difficulty of its implementation largely in experiment. It maybe have good applications in quantum communication in future., 7 pages, 3 figures

We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with $d$-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present., Comment: 5 pages, 2 figure

We propose a different entanglement concentration protocol (ECP) for nonlocal N-electron systems in a partially entangled Bell-type pure state using the CNOT gates and the projection measurements on an additional electron. For each nonlocal N-electron system, Alice first entangles it with the additional electron, and then she projects the additional electron onto an orthogonal basis for dividing the N-electron systems into two groups. In the first group, the N parties obtain a subset of N-electron systems in a maximally entangled state directly. In the second group, they obtain some less-entangled N-electron systems, which are the resource for the entanglement concentration in the next round. By iterating the entanglement concentration process several times, the present ECP has the maximal success probability, which is the theoretical limit of an ECP, equal to the entanglement of the partially entangled state, and higher than the others. This ECP may be useful in quantum computers based on electron-spin systems in the future.