Covalent Immobilization of Penicillin G Acylase onto Fe₃O₄@Chitosan Magnetic Nanoparticles

( Xiao Min Ling ),( Xiang Yu Wang ),( Ping Ma ),( Yi Yang ),( Jie Mei Qin ),( Xue Jun Zhang ),( Ye Wang Zhang ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.5

Penicillin G acylase (PGA) was immobilized on magnetic Fe₃O₄@chitosan nanoparticles through the Schiff base reaction. The immobilization conditions were optimized as follows: enzyme/support 8.8 mg/g, pH 6.0, time 40 min, and temperature 25℃. Under these conditions, a high immobilization efficiency of 75% and a protein loading of 6.2 mg/g-support were obtained. Broader working pH and higher thermostability were achieved by the immobilization. In addition, the immobilized PGA retained 75% initial activity after ten cycles. Kinetic parameters Vmax and Km of the free and immobilized PGAs were determined as 0.113 mmol/min/mg-protein and 0.059 mmol/min/mg-protein, and 0.68 mM and 1.19 mM, respectively. Synthesis of amoxicillin with the immobilized PGA was carried out in 40% ethylene glycol at 25℃ and a conversion of 72% was obtained. These results showed that the immobilization of PGA onto magnetic chitosan nanoparticles is an efficient and simple way for preparation of stable PGA.

MEROMORPHIC FUNCTIONS SHARING A NONZERO POLYNOMIAL CM

Xiao-Min Li,Ling Gao 대한수학회 2010 대한수학회보 Vol.47 No.2

In this paper, we prove that if fnf0 − P and gng0 − P share 0 CM, where f and g are two distinct transcendental meromorphic functions,n ≥ 11 is a positive integer, and P is a nonzero polynomial such that its degree γP ≤ 11, then either f = c1ecQ and g = c2e−cQ, where c1, c2and c are three nonzero complex numbers satisfying (c1c2)n+1c2 = −1,Q is a polynomial such that Q =∫z 0 P(η)dη, or f = tg for a complex number t such that tn+1 = 1. The results in this paper improve those given by M. L. Fang and H. L. Qiu, C. C. Yang and X. H. Hua, and other authors.

Model Prediction Control Design for Inverse Multiplicative Structure Based Feedforward Hysteresis Compensation of a Piezo Nanopositioning Stage

Min Ming,Jie Ling,Zhao Feng,Xiaohui Xiao 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.11

The inherent hysteresis nonlinearity of piezoelectric actuators seriously deteriorates the tracking performance of piezo-actuated nanopositioning stage, especially in large stroke applications. Usually, the model of piezo-actuated stage is given by cascading a rateindependent hysteresis submodel with a linear dynamics submodel. This paper develops a composite model predictive control (MPC) with feedforward hysteresis compensation based on the inverse multiplicative structure. The feedforward controller has the merit of non-inverse requirement. The linear MPC is utilized as a feedback controller with the feature of simple solution for the feedforward compensation system. Experimental tracking results of sinusoidal signals at different frequencies as well as complex signals show that the proposed method can improve the tracking performance of the piezo-actuated stage, verifying its effectiveness.

DNA Microarray Probe Preparation by Gel Isolation Nested PCR

( Hong Min Wang ),( Wen Li Ma ),( Hai Huang ),( Wei Wei Xiao ),( Yan Wang ),( Wen Ling Zheng ) 생화학분자생물학회 2004 BMB Reports Vol.37 No.3

To develop a simplified method that can rapidly prepare DNA microarray probes in a massive scale, a lambda phage genomic DNA-fragments library was constructed for the microarray-probes collection. Four methods of DNA band recovery from the first PCR products were tested and compared. The DNA microarray probes were collected by a novel method of nested PCR that was mediated by gel isolation of the first PCR products. This method was named GIN-PCR. The probes that were prepared by this GIN-PCR technique were used as subjects to fabricate a DNA microarray. The results showed that a wooden toothpick was superior to the other 3 methods, since this technique can steadily transfer the DNA bands as the template of the second PCR after the first PCR. A group of probes were successfully collected and DNA microarrays were constructed using these probes. Hybridization results demonstrated that this technique of DNA recovery and probe preparation was rapid, efficient, and effective. We developed a cost-effective and less labor-intensive method for DNA microarray probe preparation by nested PCR that is mediated by wooden toothpick transfer of the DNA bands in the gel after electrophoresis.

Signal Transformed Internal Model Control for Non-raster Scanning of Piezo-actuated Nanopositioning Stages

Jie Ling,Zhao Feng,Min Ming,Zhao Guo,Xiaohui Xiao 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.8

This paper proposes a new signal transformed internal model control (STIMC) scheme for non-raster scanning patterns of piezo-actuated nanopositioning stages. To smooth the scanning signals superimposed with a ramp or time-varying amplitudes, a signal transformation operator is calculated to convert the references into standard harmonic waveforms. An inverse transformation operator is then added in the control loop to generate the driving signals. For the contained internal model control (IMC) design, an H∞ mixed-sensitivity method is utilized for the first order internal mode synthesis. A second and a third internal modes are included in the IMC for alleviating residual high-frequency errors resulted from the nonlinearity of hysteresis. To verify the proposed STIMC scheme, comparative experiments with conventional IMC are conducted based on a nanopositioning platform. Results prove that the STIMC is effective on non-raster signals’ tracking. A same tracking precision for Lissajous scanning can be obtained by STIMC compared with IMC. An improvement of larger than 50% and 80% of root-mean-square errors can be obtained for cycloid and spiral scanning patterns, respectively.

Damping Controller Design for Triangular Scanning of a Third-Order Nanopositioning Stage

Jie Ling,Tingting Ye,Zhao Feng,Min Ming,Xiaohui Xiao 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

In this paper, a design procedure of damping controller for third-order nanopositioning stage is presented for high-speed triangular scanning. Conventionally, damping control schemes of integral resonant control (IRC) and resonance-shifted IRC (RS-IRC) are designed providing that a second-order model can be identified for a nanopositioning stage. For a third-order system, existing control schemes cannot be applied directly. For this, a pole-zero cancellation technique is presented to design IRC scheme. In addition, a state observer based pole placement technique is proposed for RS-IRC design. The effectiveness of the proposed design procedures is demonstrated through both simulations and experiments based on a piezo-actuated nanopositioning stage platform. Results show that a closed-loop bandwidth of 156 Hz and 186 Hz are obtained by designed IRC and RS-IRC for the third-order nanopositioning stage, and the root-mean-square (RMS) errors of 40 Hz triangular tracking are 49 nm and 13 nm under IRC and RS-IRC control, respectively.

Damping Controller Design for Nanopositioners: A Hybrid Reference Model Matching and Virtual Reference Feedback Tuning Approach

Jie Ling,Zhao Feng,Min Ming,Xiaohui Xiao 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.1

Conventionally, fixed-structure feedback controllers are designed by model-based approaches. However, such controllers are not necessarily ideal and optimal when connecting with the actual plant because of the existence of modeling uncertainty. In this paper, a paralleled damping controller as well as a novel hybrid reference model matching (RMM) and virtual reference feedback tuning (VRFT) approach for parameters’ tuning of the controller is presented. The composite damping controller for piezo-actuated nanopositioners is fixed-structure and low-order that uses a high-gain notch filter and a high-pass resonant controller to damp the first resonant peak. The proposed hybrid tuning approach combines an identified system model and a set of experimental input/output data into the parameters’ optimization of the proposed composite damping controller. The proposed hybrid approach simplifies the tuning process by decreasing the number of the parameters in the initial values’ choosing stage from the whole nine to four. Besides, the application of experimental data improves rejection of model uncertainty. A set of optimal parameters in the controller is obtained using the proposed hybrid design approach. Experimental results with comparisons to built-in PID controller are presented to show the effectiveness of the composite damping controller optimized via the hybrid approach.

Transcriptomics and identification of candidate chemosensory genes in antennae of Conogethes punctiferalis (Lepidoptera: Crambidae)

Wei Xiao-Min,Ling Yang,Zhifeng Xu,Lin He 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.4

To investigate chemoreception genes in Conogethes punctiferalis, antennal transcriptome ofmale and female samples were sequenced and analyzed. A total number of 54,442,128 and 51,132,998 clean reads from male and female samples were obtained respectively. By de novo assembly, a total of 51,240 unigenes for both sexes was generated. Among all unigenes, 26,509 showed similarity to known proteins after alignment to Nr protein database by blastx. Go analysis, KEGG pathway analysis and Protein coding region prediction were also performed subsequently to annotate gene functions. A total of 29 candidate odorant binding proteins (OBPs) including 2 general odorant binding proteins (GOBPs) and 5 pheromone binding protein (PBP), as well as 59 odorant receptors (ORs)were identified. Additionally, 10 chemosensory proteins (CSPs) and 19 ionotropic receptors (IRs)were annotated. With gene expression comparison, 920 up-regulated and 684 down-regulated genes were found in female antennae transcriptome, comparedwith that of themale. Differently expression levels of 9 chemosensory genes including PBPs up-regulated in the male were detected. Results of this study provide basic information about C. punctiferalis chemoreception genes, which helps to understand pheromone communication in this species and may benefit control of this pest with pheromonal techniques.

MEROMORPHIC FUNCTIONS SHARING A NONZERO POLYNOMIAL CM

Li, Xiao-Min,Gao, Ling Korean Mathematical Society 2010 대한수학회보 Vol.47 No.2

In this paper, we prove that if $f^nf'\;-\;P$ and $g^ng'\;-\;P$ share 0 CM, where f and g are two distinct transcendental meromorphic functions, $n\;{\geq}\;11$ is a positive integer, and P is a nonzero polynomial such that its degree ${\gamma}p\;{\leq}\;11$, then either $f\;=\;c_1e^{cQ}$ and $g\;=\;c_2e^{-cQ}$, where $c_1$, $c_2$ and c are three nonzero complex numbers satisfying $(c_1c_2)^{n+1}c^2\;=\;-1$, Q is a polynomial such that $Q\;=\;\int_o^z\;P(\eta)d{\eta}$, or f = tg for a complex number t such that $t^{n+1}\;=\;1$. The results in this paper improve those given by M. L. Fang and H. L. Qiu, C. C. Yang and X. H. Hua, and other authors.

Differential Impacts on Bacterial Composition and Abundance in Rhizosphere Compartments between Al-Tolerant and Al-Sensitive Soybean Genotypes in Acidic Soil

Wen Zhong-Ling,Yang Min-Kai,Fazal Aliya,Liao Yong-Hui,Cheng Lin-Run,Hua Xiao-Mei,Hu Dong-Qing,Shi Ji-Sen,Yang Rong-Wu,Lu Gui-Hua,Qi Jin-Liang,Zhi Hong,Qian Qiu-Ping,Yang Yong-Hua 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.8

In this study, two soybean genotypes, i.e., aluminum-tolerant Baxi 10 (BX10) and aluminumsensitive Bendi 2 (BD2), were used as plant materials and acidic red soil was used as growth medium. The soil layers from the inside to the outside of the root are: rhizospheric soil after washing (WRH), rhizospheric soil after brushing (BRH) and rhizospheric soil at two sides (SRH), respectively. The rhizosphere bacterial communities were analyzed by high-throughput sequencing of V4 hypervariable regions of 16S rRNA gene amplicons via Illumina MiSeq. The results of alpha diversity analysis showed that the BRH and SRH of BX10 were significantly lower in community richness than that of BD2, while the WRH exhibited no significant difference between BX10 and BD2. Among the three sampling compartments of the same soybean genotype, WRH had the lowest community richness and diversity while showing the highest coverage. Beta diversity analysis results displayed no significant difference for any compartment between the two genotypes, or among the three different sampling compartments for any same soybean genotype. However, the relative abundance of major bacterial taxa, specifically nitrogen-fixing and/or aluminum-tolerant bacteria, was significantly different in the compartments of the BRH and/or SRH at phylum and genus levels, indicating genotype-dependent variations in rhizosphere bacterial communities. Strikingly, as compared with BRH and SRH, the WRH within the same genotype (BX10 or BD2) always had an enrichment effect on rhizosphere bacteria associated with nitrogen fixation