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Coherent tripartite interactions among degrees of freedom of completely different nature are instrumental for quantum information and simulation technologies, but they are generally difficult to realize and remain largely unexplored. Here, we predict a tripartite coupling mechanism in a hybrid setup comprising a single NV center and a micromagnet. We propose to realize direct and strong tripartite interactions among single NV spins, magnons and phonons via modulating the relative motion between the NV center and the micromagnet. Specifically, by introducing a parametric drive (two-phonon drive) to modulate the mechanical motion (such as the center-of-mass motion of a NV spin in diamond trapped in an electrical trap or a levitated micromagnet in a magnetic trap), we can obtain a tunable and strong spin-magnon-phonon coupling at the single quantum level, with up to two orders of magnitude enhancement for the tripartite coupling strength. This enables, for example, tripartite entanglement among solid-state spins, magnons, and mechanical motions in quantum spin-magnonics-mechanics with realistic experimental parameters. This protocol can be readily implemented with the well-developed techniques in ion traps or magnetic traps, and could pave the way for general applications in quantum simulations and information processing based on directly and strongly coupled tripartite systems., To appear in PRL, 9 pages, 4 figures

Spin-mechanical hybrid systems have been widely used in quantum information processing. However, the spin-mechanical interaction is generally weak, making it a critical challenge to enhance the spin-mechanical interaction into the strong coupling or even ultra-strong coupling regime. Here, we propose a protocol that can significantly enhance the spin-mechanical coupling strength with a diamond spin vacancy and a levitated micromagnet. A driving electrical current is used to modulate the mechanical motion of the levitated micromagnet, which induces a two-phonon drive and can exponentially enhance the spin-phonon and phonon-medicated spin-spin coupling strengths. Furthermore, a high fidelity Schrodinger cat state and an unconventional 2-qubit geometric phase gate with high fidelity and faster gate speed can be achieved using this hybrid system. This protocol provides a promising platform for quantum information processing with NV spins coupled to levitated micromagnets., Comment: 13 pages, 8 figures

The expansion and deletion instabilities shown by some trinucleotide repeated DNA sequences are associated with more than 50 neurodegenerative diseases in humans. The increase or decrease of the trinucleotide repeat units underlying the diseases are not yet clearly explained using any mechanism, but has been found to affect the expression of specific genes, or produces cytotoxic RNA and protein, which has now become a common pathological mechanism of the diseases. The ongoing studies have shown that the changes in the copy numbers of the disease-related trinucleotide repeats may result from abnormal DNA replication, repair, recombination, and gene transcription. Human genetical studies also suggest that abnormal DNA replication, repair, recombination, or gene transcription that occurred in the disease-related trinucleotide repeat DNA sites may play a key role in the trinucleotide repeat DNA instabilities. Based on the research experiences of our research group, this paper reviews the recent research progress on the mechanisms of the disease-associated trinucleotide repeat DNA instabilities including their base mutation instabilities, the amplification and deletion instabilities of the repeat units, to better understand the molecular mechanism of the disease-associated trinucleotide repeats instabilities.三核苷酸重复DNA序列扩增或缺失不稳定性与50多种人类神经退行性疾病有关。与疾病相关的三核苷酸重复拷贝数的增加或减少,影响了特定基因的表达,或因之产生具有细胞毒性的RNA和蛋白质已成为相关疾病的共有病理机制。现有的研究表明,疾病相关的三核苷酸重复拷贝数的改变有可能起因于相关三核苷酸重复DNA序列的异常DNA复制、修复、重组以及基因转录。有关人类遗传学研究也提示,发生在疾病相关的三核苷酸重复DNA部位的异常DNA复制、修复、重组或基因转录确有可能在三核苷酸重复DNA不稳定过程中发挥着关键作用。本文根据本课题组的研究经验,综述了近年来有关疾病相关三核苷酸重复不稳定性机制的研究进展,包括碱基突变不稳定、重复单元的扩增和缺失不稳定,以助更好地理解疾病相关三核苷酸重复DNA序列不稳定性的分子机制。.

SMARCAL1 is an ATP-driven DNA annealing helicase that is similar in structure to the chromatin regulators in the subfamily A group of the SWI/SNF-related matrix-associated actin-dependent chromatin regulators. SMARCAL1 catalyzes the formation of dsDNA by annealing the single-stranded binding protein RPA coated ssDNA with its complementary strand both

Background:Although the pathogenesis of glaucoma is not fully understood ,an elevated intraocular pressure (IOP) is a major factor contributing to its development and progression. The aim of this study was to investigate the changes in the retinal blood flows of the macula and optic nerve head (ONH) after an acute elevation in the intraocular pressure (IOP) observed using optical coherence tomography angiography (OCTA). Methods: This was a prospective comparative study of subjects with narrow anterior chamber angles who underwent laser peripheral iridotomies (LPIs). The IOP was measured before and one hour after the LPI. The retinal blood flows of the macula and ONH were measured using OCTA at the baseline and one hour after the LPI. Results: A total of 64 eyes of 51 individuals were enrolled in this study, and 58 eyes of 43 individuals finally completed the study with a mean IOP rise of 10.5 ± 7.6 mmHg after the LPI. Based on the magnitude of the rise in the IOP, we divided the subjects into three groups: group A = IOP rise ≤ 10 mmHg, group B = 10 mmHg < IOP rise ≤ 20 mmHg, and group C = IOP rise > 20 mmHg. The vessel density did not differ after the acute IOP elevation in either the macular region or papillary region in group A or group B (p > 0.05), but there was a significant difference in group C (p < 0.05). However, when the subjects were not separated into groups, the vessel densities of the ONH and macular region did not differ between the measurements obtained at the baseline and one hour after the LPI (p>0.05). Conclusion: In these normal subjects, an acute mild or moderate IOP elevation for one hour after the LPI did not affect the blood flow in the macula or ONH, as examined using OCTA. However, when the IOP rise was greater than 20 mmHg, the macular and papillary blood flows decreased significantly.

To establish a method for isolation, cryopreservation and recovery of the highly viable human peripheral blood monomuclear cells (PBMNCs) so as to achieve the long-term preservation of PBMNCs.A total of 80-100 ml peripheral blood were collected from the healthy volumteers aged over 50 years old. The PBMNCs were isolated by the Ficoll density gradient technique and cryopreserved gradually by program control method in liquid nitrogen freezer of -196 °C. The serum-free medium and autoloqous plasma medium were test for preservation of PBMNCs. The cell viability was assessed at time point of 1, 2, 4, 8, 12 and 24 months after thawing. Finally, the proliferation ability, purity and cytotoxicity were compared between the autologous immune lymphocytes (AIL) induced from cryopreserved PBMNCs and AIL as control from fresh PBMNCs.After separating, the cell viability was 99.6%±0.4%, and the recovery rate of lymphocytes was 58.4%±6.52%. The cell recovery rate of lymphocyte was 89.7%±3.82% at 24 months. The quality assurance program was reliable within 2 years of running. The AIL cells induced with cryopreserved PBMNCs were not significantly different from those induced from fresh PBMNCs in terms of proliferative action, purity and cytotoxicity(CD3(+)CD8(+) ≥45%,CD3(+)CD56(+) NKT≥10%,CD4(+)CD25(+) NKT≤10%).Manual separation of lymphocytes in vitro can get enough high-quality PBMNCs. The long-term cryopreserved PBMNC still maintain their high viability. The reinfusion of the clinical autologous immune cells would be advantageous for early tumor immunotherapy. Human AIL induced from cryopreserved PBMNC maintain their anti-tumor ability. These findings have the important implications for the application of these cells to adoptive cellular therapy.

Cloud computing has become a main medium for Software as a Service (SaaS) hosting as it can provide the scalability a SaaS requires. In the composite SaaS placement process， it should consider the factors about the size of the cloud network, SaaS interactions between its components and SaaS interactions with its data components. A previous research has tackled this problem using a genetic algorithm (GA) approach. This paper proposes an ant colony optimization (ACO) approach. The ACO for the SaaS placement problem has been implemented and evaluated.

Chiral molecule C17H17CIO6 was incorporated in MMA by sol-gel process and its optical polarization response was measured. The optical rotatory dispersion was measured with self-manufactured apparatus. The results show that the maximum and minimum rotation angles of the chiral PMMA are 69° at the wavelength of 450 nm and 17° at the wavelength of 700 nm, respectively. The experimental results accord with the simulation results by the Boltzmann formula.

Simple sequence repeats (SSR) distribute extensively in genomes of all organisms, but the molecular mechanism underlined is poorly understood. In this study, we characterized distribution and biological significance of the simple repetitive DNA sequences in the D-loop region in mitochondria DNA of 256 mammal species, and classified the mammal carriers into three groups including 53 species with hexanucleotide repeats, 104 species with other types of simple repeats (6 bp) and 99 species without any repeat sequences, respectively. Furthermore, we found that the hexanucleotide repeats dispersed significantly in the interval space between CSB1 and CSB2, while other repeats dispersed mainly in the termination region, central conserved region and the conserve sequence block (CSB) regions. In addition, comparison on the base composition and the DNA contexts of the central conserved region, CSB1, CSB2, and CSB3 revealed a lack of significant differences in similarity among different species with or without repeat sequences. Moreover, a phylogenetic analysis with 256 mammal species using N-J method suggested loss of the repeat sequences in mammals in evolution.

Pulmonary hypertension is a kind of disease associated with a very high rate of mortality, and there are not many effective drugs for the treatment. Today, endothelin (ET)-1 receptor antagonists were proved to be effective in the treatment of pulmonary hypertension. Aiming at developing new endothelin-A receptor (ETA) antagonist for treatment of pulmonary hypertension, di-n-butylaminocarbamyl-l-leucyl-d-tryptophanyl-d-4-chloro-Phe, named GF063, was synthesized at base of selective ETA receptor antagonist BQ485 and selected for the further pharmacological characterization. The preliminary pharmacodynamics of GF063 was evaluated by radioligand receptor binding assay and test of antivasoconstriction effects in vitro and in vivo. The integrative pharmacodynamics was evaluated in hypoxia-induced rat pulmonary hypertension. In vitro, GF063 bound to ETA receptor with 100,000-fold higher affinity than to ETB receptor. GF063 concentration dependently inhibited contraction of isolated rat aortic ring induced by ET-1 and shifted the cumulative concentration-contraction response curve to right with no change in the maximal response. In vivo, GF063 inhibited the increase of mean systemic arterial pressure induced by ET-1 in anesthetized rat. In hypoxia-induced rat pulmonary hypertension model, pretreatment with GF063 (40 mg/kg, s.c.) significantly decreased pulmonary artery pressure and right ventricular hypertrophy, also significantly inhibited the increase of ET-1 level in lung, improved hemodynamics, and alleviated the wall thickness of pulmonary vessels. This study indicated that GF063, as a selective ETA receptor antagonist, could inhibit vasoconstriction effects in vivo and in vitro, could prevent pulmonary hypertension induced by hypoxia, and may have great potential to be developed as a new drug of antipulmonary hypertension.

Based on the OFDM technique and the character of cognitive radio (CR), a multiuser WiMAX resource allocation algorithm is proposed. In the algorithm, cognitive users use the vacant spectrum resources under the condition of not interfering the primary users based on the spectrum information detections. Make use of water-filling algorithm to one or more users requesting the use of same subcarrier to carry through the arbitration, moreover, achieve subcarrier, bit and power allocation satisfying the bit rate and QoS demand, and bring the total transmit power to the minimum. Simulation results indicate that our method has the lower transmit power and better performance compared with static algorithms.

Effects of degU32 (Hy), degR genes from Bacillus subtilis 168 and degQa gene from Bacillus amyloliquefaciens on Bacillus subtilis Ki-2-132 cell growth, sporulation and protease fermentation were investigated by introducing these genes into B. subtilis Ki-2-132 chromosome and/or cytoplasm. Although the genes come from different species and strains, they showed pleiotropic effects in B. subtilis Ki-2-132. B. subtilis Ki-2-132degU32 (Hy) showed increased protease production, and when cooperating with degQa either in plasmid or in chromosome, further altered cell growth, increased protease production and affected the spore formation in a glucose and dosage dependent manner. By contrast, degR did not significantly affect the protease productivity in degU32 (Hy) mutant, consisting with that DegR was used to stabilise DegU-phosphate, which in degU32 (Hy) strain no longer further amplify the DegU-phosphate effect.

The mechanism underlying CAG.CTG CGG.CCG and GAA.TTC trinucleotide repeats expansion and contraction instabilities has not been clearly understood. Investigations in vitro have demonstrated that the disease causing repeats are capable of adopting non-B secondary structures that mediate repeats expansion. However, in vivo, similar observations have not been easily made so far. Investigations on the non-B secondary structure formation using E.coli, yeast etc cannot simulate the suggested repeats expansion instability. These could leave a space to infer a disassociation of the suggested repeats non-B secondary structure formation and the repeats expansion in vivo. Although longer trinucleotide repeats may be theoretically easier to form non-B DNA secondary structures in replication or in post-replication, however such non-B secondary structures are likely to cause repeat fragility rather than repeat expansion. In fact, repeat expansion as seen in patients may not necessarily require trinucleotide repeats to form non-B secondary structures, instead the repeat expansions can be produced through a RNA transcription-stimulated local repeat DNA replication and a subsequent DNA rearrangement.

Recently, the propagation characteristics of waveguides or fibers filled with homogeneous chiral media were studied widely. But most of the chiral molecule was at the state of liquid. So further basic research and application research has been restricted and seeking suitable solid chial material was becoming the key of minimizing and practical development. One way of manufacture solid chiral material is sol-gel method. In this paper, using TEOS, C 2 H 5 OH and N, N-dimethyl formamide dimethyl aceta as precursor, the chiral molecule C 17 H 17 ClO 6 was uniformly incorporated in gel by sol-gel process. So the sol-gel material containing C 17 H 17 ClO 6 was fabricated successfully. Its polarization response was investigated. By using several different kinds of light sources which own different wavelength, we test the optical rotatory dispertion of chiral sol-gel material containing C 17 H 17 ClO 6 . By calculation, we obtain chiral parameter at different optical wavelength. In order to find out which state the chiral molecule C 17 H 17 ClO 6 maybe in the sol-gel material, the infrared absorption spectra are measured.