Qianzhou, China
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Tang B.,JiShou University
International Journal of Theoretical Physics | Year: 2017

A theoretical work on modulational instability and quantum local breather modes in a one-dimensional easy-axis Heisenberg ferromagnetic spin lattice with the Dzyaloshinskii-Moriya interaction is completed in the Hartree approximation. By means of the discrete modulational instability analysis, we discuss the influence of the Dzyaloshinskii-Moriya interaction on modulational instability regions and predict the presence condition for the bright stationary localized solution. We find that that the region of the modulational instability moves to the left of the Brillouin zone because of the introduction of the Dzyaloshinskii-Moriya interaction, which is a new finding. Moreover, we get the analytical bright stationary localized solution and analyze the influence of the on-site easy-axis anisotropy and the Dzyaloshinskii-Moriya interaction on their appearance conditions. By the use of such bright stationary localized single-boson wave functions, we construct the quantum breather state that has obvious quantum properties. In addition, the role of the easy-axis anisotropy and the Dzyaloshinskii-Moriya interaction on quantum breather modes is discussed. © 2017 Springer Science+Business Media New York


Xiao L.,JiShou University
Neural Computing and Applications | Year: 2017

In this paper, a finite-time convergent Zhang neural network (ZNN) is proposed and studied for matrix square root finding. Compared to the original ZNN (OZNN) model, the finite-time convergent ZNN (FTCZNN) model fully utilizes a nonlinearly activated sign-bi-power function, and thus possesses faster convergence ability. In addition, the upper bound of convergence time for the FTCZNN model is theoretically derived and estimated by solving differential inequalities. Simulative comparisons are further conducted between the OZNN model and the FTCZNN model under the same conditions. The results validate the effectiveness and superiority of the FTCZNN model for matrix square root finding. © 2017 The Natural Computing Applications Forum


In this paper, a new design formula is presented to accelerate the convergence speed of a recurrent neural network, and applied to time-varying matrix square root finding in real time. Then, according to such a new design formula, a finite-time Zhang neural network (FTZNN) is proposed and investigated for finding time-varying matrix square root. In comparison with the original Zhang neural network (ZNN) model, the FTZNN model makes a breakthrough in the convergence performance (i.e., from infinite time to finite time). In addition, theoretical analyses of the design formula and the FTZNN model are provided in details. Comparative results further verify the superiority of the proposed FTZNN model to the original ZNN model for finding time-varying matrix square root. © 2017 The Franklin Institute.


Sylvester equation is widely used to study the stability of a nonlinear system in the control field. In this paper, a finite-time Zhang neural network (FTZNN) is proposed and applied to online solution of time-varying Sylvester equation. Differing from the conventional accelerating method, the design of the proposed FTZNN model is based on a new evolution formula, which is presented and studied to accelerate the convergence speed of a recurrent neural network. Compared with the original Zhang neural network (ZNN) for time-varying Sylvester equation, the FTZNN model can converge to the theoretical time-varying solution within finite time, instead of converging exponentially with time. Besides, we can obtain the upper bound of the finite convergence time for the FTZNN model in theory. Simulation results show that the proposed FTZNN model achieves the better performance as compared with the original ZNN model for solving online time-varying Sylvester equation. © 2017 Springer Science+Business Media B.V.


The recently-proposed Zhang dynamics (ZD) has been proven to achieve success for solving the linear-equality constrained time-varying quadratic program ideally when time goes to infinity. The convergence performance is a significant improvement, as compared to the gradient-based dynamics (GD) that cannot make the error converge to zero even after infinitely long time. However, this ZD model with the suggested activation functions cannot reach the theoretical time-varying solution in finite time, which may limit its applications in real-time calculation. Therefore, a nonlinearly-activated neurodynamic model is proposed and studied in this paper for real-time solution of the equality-constrained quadratic optimization with nonstationary coefficients. Compared with existing neurodynamic models (specifically the GD model and the ZD model) for optimization, the proposed neurodynamic model possesses the much superior convergence performance (i.e., finite-time convergence). Furthermore, the upper bound of the finite convergence time is derived analytically according to Lyapunov theory. Both theoretical and simulative results verify the efficacy and superior of the nonlinearly-activated neurodynamic model, as compared to these of the GD and ZD models. © 2015 Elsevier B.V. All rights reserved.


To investigate the diversity of cultivable halophilic and halotolerant bacteria isolated from ordinary non-saline soil samples collected from Xiaoxi National Natural Reserve (28 degrees 42' 15"-28 degrees 53' 15" N, 110 degrees 6' 50"-110 degrees 21' 35" E), Hunan Province, China. Bacterial strains were isolated from the samples by using the conventional culture-dependent method and investigated by using phylogenetic analysis based on 16S rRNA gene sequence comparisons. We isolated 114 bacterial strains (8 moderately halophilic, 19 slightly halophilic, 87 halotolerant) from the samples on media (marine agar 2216, International Streptomyces Project medium 2 and 5, nutrient and humic acid agars) supplemented with 5% to 20% (w/v) NaCl. On the basis of morphological, physiological and biochemical characteristics, we selected 61 strains to perform a phylogenetic analysis based on 16S rRNA gene sequences. Results showed that 61 isolates represented 41 species, belonging to 18 genera (Actinomadura, Arthrobacter, Bacillus, Brachybacterium, Brevibacterium, Erwinia, Halobacillus, Jeotgalibacillus, Microbacterium, Microbulbifer, Nocardia, Pseudomonas, Rheinheimera, Rhodococcus, Sphingomonas, Staphylococcus, Streptomyces, Yaniella) of 16 families ( Alteromonadaceae, Bacillaceae, Brevibacteriaceae, Chromatiaceae, Dermabacteraceae, Enterobacteriaceae, Microbacteriaceae, Micrococcaceae, Nocardiaceae, Planococcaceae, Pseudomonadaceae, Sphingomonadaceae, Staphylococcaceae, Streptomycetaceae, Thermomonosporaceae, Yaniellaceae) in three phyla (Actinobacteria, Firmicutes, Proteobacteria). The most abundant and diverse isolates were within the phylum Firmicutes (38 strains; 62.3%) and the phylum Actinobacteria (18 strains; 29.5%). The phylogenetic distance matrix results suggested that there were obvious genetic divergences between most isolates and their closestly related type strains (16S rRNA gene sequence similarities ranged from 96.9% to 99.8%), and that, out of 61 isolates, at least 7 strains (JSM 070026, JSM 081004, JSM 081006, JSM 081008, JSM 083058, JSM 083085, JSM 084035) should represent 7 potential novel species within 6 characterized genera (Yaniella, Bacillus, Jeotgalibacillus, Sphingomonas, Rheinheimera, Microbulbifer). The results presented here showed that there is abundant diversity of halophilic and halotolerant bacteria, as well as a number of novel species in non-saline soil collected from Xiaoxi National Natural Reserve, Hunan Province, China.


Xiong L.,JiShou University | He Z.,JiShou University
Polymer - Plastics Technology and Engineering | Year: 2013

Methoxy polyethylene glycol and poly(D, L-lactide) (mPEG/PLA) copolymers with various composition were synthesized by using ring-opening polymerization method and characterized by Fourier transform infrared spectroscopy (FT-IR). mPEG/PLA microspheres were prepared by double emulsion method. 5-fluorouracil (5-FU), as an anticancer drug, was successfully loaded in these microspheres. The obtained microspheres were characterized for entrapment efficiency, drug loading, and in-vitro release studies and subjected to optical microscopy and scanning electron microscopy (SEM). The results indicated that the microspheres showed spherical shape, homogeneous particle size distribution and smooth surfaces. The percentage of loading and encapsulation efficiency of 5-FU decreased with increasing amount of mPEG in the microspheres and decreasing concentration of mPEG/PLA. 5-FU showed a typical bimodal in-vitro release behavior from mPEG/PLA microspheres and the release kinetics indicated Fickian diffusion. In-vitro cytotoxicity analysis on HT-29 cell lines demonstrated that 5-FU loaded mPEG/PLA microspheres possess the potential to delay the apoptosis for a long time. © 2013 Copyright Taylor and Francis Group, LLC.


Xiong L.,JiShou University | He Z.,JiShou University
Polymer - Plastics Technology and Engineering | Year: 2012

Blend microspheres of poly(vinyl alcohol) (PVA) with chitosan (Cs) were prepared as candidates for oral delivery system. Cs/PVA microspheres containing 2,4-dihydroxy-5-fluoropyrimidine (5-FU) were obtained using glutaraldehyde (GA) as a cross-linking agent. The effects of cross-linker concentration and cross-linking time on the release of 5-FU were investigated, and the cytotoxicities of free 5-FU and the PVA/Cs microspheres loaded with 5-FU were also studied. It was observed that 5-FU release from the microspheres decreased with the increase of cross-linking concentration and cross-linking time. Cytotoxicity tests of free and entrapped 5-fluorouracil were carried out with MCF-7 breast cancer cell line. Free 5-FU produced an immediate effect, whereas entrapped 5-fluorouracil showed a prolonged cytotoxic effect. © 2012 Copyright Taylor and Francis Group, LLC.


A Gram-stain-positive, endospore-forming, motile, catalase- and oxidase-positive, aerobic, rod-shaped bacterium, designated strain JSM 081008(T), was isolated from non-saline forest soil in China. Strain JSM 081008(T) was able to grow with 0-20% (w/v) NaCl, at pH 6.0-10.5 and at 10-45 degrees C; optimum growth was observed with 2-5% (w/v) NaCl, at pH 7.0-8.0 and at 30-35 degrees C. The peptidoglycan type was A1alpha linked directly through L-Lys. The major cellular fatty acids (>10% of the total) were anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0. The predominant respiratory quinone was menaquinone 7 and the genomic DNA G + C content of the strain was 42.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JSM 081008(T) should be assigned to the genus Jeotgalibacillus and was related most closely to the type strains of Jeotgalibacillus alimentarius (sequence similarity 99.4%) and Jeotgalibacillus salarius (97.0%), followed by Jeotgalibacillus campisalis (95.4%) and Jeotgalibacillus marinus (95.2%). The combination of phylogenetic analysis, DNA-DNA relatedness values, phenotypic characteristics and chemotaxonomic data supports the view that strain JSM 081008(T) represents a novel species of the genus Jeotgalibacillus, for which the name Jeotgalibacillus soli sp. nov. is proposed. The type strain is JSM 081008(T) (=DSM 22174(T) = KCTC 13528(T)). An emended description of the genus Jeotgalibacillus is also presented.


Chen Y.G.,JiShou University
Antonie van Leeuwenhoek | Year: 2010

A novel Gram-stain-positive, slightly halophilic, facultatively alkaliphilic, non-motile, non-sporulating, catalase-positive, oxidase-negative, aerobic bacterium, designated strain JSM 070026(T), was isolated from non-saline forest soil in China. Growth occurred with 0-20% (w/v) NaCl (optimum, 2-4%) and at pH 6.0-10.5 (optimum, pH 8.0) and 5-40 degrees C (optimum, 30 degrees C). Good growth also occurred in the presence of 0-28% (w/v) KCl (optimum, 2-5%) or 0-25% (w/v) MgCl(2)*6H(2)O (optimum, 1-4%). The peptidoglycan type was A4alpha (L: -Lys-Gly-L: -Glu). Cell-wall sugars contained mannose and xylose. The major cellular fatty acids were anteiso-C15:0 and iso-C15:0. Strain JSM 070026(T) contained menaquinone 8 as the major respiratory quinone and diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol as the major polar lipids. The DNA G + C content of strain JSM 070026(T) was 56.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JSM 070026(T) was a member of the suborder Micrococcineae and most closely related to Yaniella flava YIM 70178(T) (sequence similarity 99.4%) and Yaniella halotolerans YIM 70085(T) (97.9%). The three strains formed a distinct branch in the phylogenetic tree. The combination of phylogenetic analysis, DNA-DNA relatedness values, phenotypic characteristics and chemotaxonomic data supports the proposal that strain JSM 070026(T) represents a novel species of the genus Yaniella, for which the name Yaniella soli sp. nov. is proposed. The type strain is JSM 070026(T) (=DSM 22211(T) = KCTC 13527(T)).

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