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Optimized human factor IX expression cassettes for hepaticdirected gene therapy of hemophilia B

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Frontiers of Medicine 2015年第1期9卷 90-99页

作者： ru Zhang qiang Wang Lin Zhang Saijuan Chen State Key Laboratory for Medical Genomics Shanghai Institute of Hematology Ruifin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200025 China

Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use of a self-complementary adeno-associated virus serotype 8-human codon-optimized factor IX （AAV8-hFIXco） vector demonstrated encouraging efficacy with hFIX expression stabilized at 1% to 6% of normal level in patients, but safety concerns related to high vector doses are still present. Thus, further improvement of AAV vectors and hFIX expression cassette may positively contribute to the ultimate success of hemophilia B gene therapy. In this study, to obtain a higher expression level of hFIX that potentiates the coagulant capacity of recipients, human FIX expression vector was optimized by upgrading the codon adaption index and adjusting the GC content, inserting a Kozak sequence （GCCACC）, and introducing a gain-of-function mutation, R338L （FIX Padua）. The efficiency of the published and the presently constructed cassettes was compared through in vivo screening. In addition, the regulatory elements that control the FIX gene expression in these cassettes were screened for liver-specific effectiveness. Among all the constructed cassettes, scAAV-Pre-hFIXco-SIH-R338L, which was the construct under the control of the prothrombin enhancer and prealbumin promoter, resulted in the highest level of coagulant activity, and the expression levels of two constructed cassettes （scAAV-Chi-hFIXco-SIH-R338L and scAAV-Pre- hFIXco-SIH-R338L） were also higher than that of the published cassette （scAAV-LPI-hFIXco-SJ）. In summary, our strategies led to a substantial increase in hFIX expression at the protein level or a remarkably elevated coagulant activity. Thus, these reconstructs of hFIX with AAV vector may potentially contribute to the creation of an efficacious gene therapy of hemophilia B.

关键词： factor IX hemophilia B liver-specific regulatory elements hydrodynamic gene transfer

Lithium intercalation mechanism for β-SnSb in Sn-Sb thin films

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 216-222页

作者： qiang ru Qin Tian She-jun Hu Ling-zhi Zhao Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China Department of Chemistry South China Normal University Guangzhou 510006 China

Based on the first-principles plane wave pseudo-potential method, the electronic structure and electrochemical performance of LixSn4Sb4 （x=2, 4, 6, and 8） and LixSn12-xSb4 （x=9, 10, 11, and 12） phases were calculated. A Sn-Sb thin film on a Cu foil was also prepared by radio frequency magnetron sputtering. The surface morphology, composition, and lithium intercalation/extraction behavior of the fabricated film were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and cyclic voltammetry （CV）. Lithium atoms can easily insert into and extract out of the β-SnSb cell due to the low lithium intercalation formation energy. It is found that lithium atoms first occupy the interstitial sites, and then Sn atoms at the lattice positions are replaced by excessive lithium. The dissociative Sn atoms continue to produce different Li-Sn phases, which will affect the electrode stability and lead to the undesirable effect due to their large volume expansion ratio. The calculated lithium intercalation potential is stable at about 0.7 V, which is consistent with the experimental result.

关键词： lithium batteries first-principles Sn-Sb alloys electronic structure thin films

Study of lithium storage properties of the Sn-Ni alloys prepared by magnetic sputtering technology

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Acta Metallurgica Sinica(English Letters) 2010年第5期23卷 363-369页

作者： Xianhua HOU Shejun HU Wei PENG Zhiwen ZHANG qiang ru School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

Nano-level Sn-Ni alloy thin-film electrode materials prepared by magnetic sputtering technology are characterized with X-ray diffraction （XRD）, atom force microscopy （AFM） and scanning electron microscopy （SEM）. The charge/discharge and cyclic voltammograms （CV） of the films electrodes are tested by the battery testing system of high precision. The results indicate that the materials prepared by direct current （DC） and radio frequency （RF） methods differ greatly in their performance. Ni3Sn2 alloy phase constitutes the main components prepared by DC method, the particles on the surface are tiny and show steady cycling performance, the deficiency is that they have low initial efficiency and small discharge capacity of 72% and 108 mA·h/g, respectively. Contrary to the former, Ni3Sn4 alloy phase constitutes the main com- ponents prepared by RF method, the particles on the surface appear comparatively larger, their discharge capacity did not decline in the first 15 times, keeping above 500 mA·h/g, but began to decline after 15 times.

关键词： Lithium ion battery Sn-Ni alloy Electrochemical property

Properties of TiAICrN coatings prepared by vacuum cathodic arc ion plating

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Rare Metals 2008年第3期27卷 251-256页

作者： ru qiang HU Shejun HUANG Nacan ZHAO Lingzhi QIU Xiuli HU Xianqi School of Physics and Communication Engineering South China Normal University Guangzhou 510006 China Faculties of Materlals and Energy Guangdong University of Technology Guangzhou 510006 China Shenzhen Goldenhouse Vacuum Technology Co. Ltd. Shenzhen 518053 China

TiAlCrN coatings were deposited by means of vacuum cathodic arc ion plating technique on TC 11 （Ti-6.5Al-3.5Mo-1.5Zr-0.3Si） titanium alloy substrates. The composition, phase structure, mechanical performance, and oxidation-resistance of the nivide coatings were investi- gated by scanning electron microscopy （SEM）, atomic force microscope （AFM）, X-ray diffraction （XRD）, auger electron spectroscopy （AES）, and X-ray photoelectron microscopy （XPS）. A new process for preparing protective coatings of the titanium alloy is successfully ac- quired. The experimental results indicate that the added element chromium in the TiAlN coatings make a contribution to form the （220） pre- ferred direction. The phases of the coatings are composed of （Ti,Al）N and （Ti,Cr）N. After 700~C and 800~C oxidation, AES analysis shows that the diffusion distribution of the TiAlCrN coatings emerges a step shape. From the outside to the inner, the concentrations of O, Al, and Cr reduce, but those of Ti and N increase. The Al-rich oxide is formed on the surface of the coatings, and the mixed structure of Ti-rich and Cr-rich oxides is formed in the internal layer. The oxidation resistance of the TiAlCrN coatings is excellent at the range of 700 to 800~C. Adhesion wear is the dominant mechanical characteristic for the titanium alloy at room temperature, and the protective coatings with high hardness can improve the mechanical properties of the titanium alloy. The wear resistance of the TC 11 alloy is considerably improved by the TiAlCrN coatings.

关键词： TiAlCrN coatings ion plating wear and friction oxidation resistance titanium alloy

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： Dong Feng Hong-qiang ru Xu-dong Luo Jie-gang You Ling Zhang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina Liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form

Performance analysis of ARQ schemes with code combining over Nakagami-m fading channel

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 14-19页

作者： XU Wen-bo NIU Kai LIN Jia-ru HE Zhi-qiang School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article investigates the performance of hybrid automatic repeat request （HARQ） with code combining over the ideally interleaved Nakagami-m fading channel. Two retransmission protocols with coherent equal gain code combining are adopted, where the entire frame and several selected portions of the frame are repeated in protocols I and II, respectively. Protocol II could be viewed as a generalization of the recently proposed reliability-based HARQ. To facilitate performance analysis, an approximation of the product of two independent Nakagami-m distributed random variables is first developed. Then the approximate analysis is utilized to obtain exact frame error probability （FEP） for protocol I, and the upper bound of the FEP for protocol II. Furthermore, the throughput performance of both two protocols is presented. Simulation results show the reliability of the theoretical analysis, where protocol II outperforms protocol I in the throughput performance due to the reduced amount of transmitted information.

关键词： code combining HARQ Nakagami-m fading performance analysis

Influence of structure and atom sites on Sn-based anode materials for lithium ion batteries: a first-principle study

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Chinese Science Bulletin 2014年第13期59卷 1459-1467页

作者： Zhaowen Huang Shejun Hu Xianhua Hou qiang ru Lingzhi Zhao Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication Engineering South China Normal University Engineering Research Center of Materials and Technology for Electrochemical Energy Storage Ministry of Education Laboratory of Nanophotonic Functional Materials and Devices Institute of Opto-Electronic Materials and Technology South China Normal University

To understand the influence of structure and atom sites on the electrochemical properties of Sn-based anode materials,the lithium intercalation–deintercalation mechanisms into SnNi2Cu and SnNiCu2phases were studied using the first-principle plane wave pseudo-potential *** results showed that both SnNi2Cu and SnNiCu2were unsuitable anode materials for lithium ion *** Sn-based anode structure related to the number of interstitial sites,theoretical specific capacity,and volume expansion *** atom sites led to different forces at interstitial sites,resulting in variations in formation energy,density of states,and hybrid orbital *** order to validate the calculated model,the SnNi2Cu alloy anode material was synthesized through a chemical reduction-codeposition *** results proved that the theoretical design was ***,when selecting Snbased alloy anodes,attention should be paid to maximizing the number of interstitial sites and distributing atoms reasonably to minimize forces at these sites and facilitate the intercalation and deintercalation of lithium ion.

关键词：锡基负极材料锂离子电池解结构原子第一原理网站 Sn 计算结果

A Deep Learning Approach for Fault Diagnosis of Induction Motors in Manufacturing

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1347-1356页

作者： Si-Yu Shao Wen-Jun Sun ru-qiang Yan Peng Wang Robert X Gao School of Instrument Science and Engineering Southeast University Department of Mechanical and Aerospace Engineering Case Western Reserve University

Extracting features from original signals is a key procedure for traditional fault diagnosis of induction motors, as it directly influences the performance of fault recognition. However, high quality features need expert knowledge and human intervention. In this paper, a deep learning approach based on deep belief networks （DBN） is developed to learn features from frequency distribution of vibration signals with the purpose of characterizing work- ing status of induction motors. It combines feature extraction procedure with classification task together to achieve automated and intelligent fault diagnosis. The DBN model is built by stacking multiple-units of restricted Boltzmann machine （RBM）, and is trained using layer-by- layer pre-training algorithm. Compared with traditional diagnostic approaches where feature extraction is needed, the presented approach has the ability of learning hierar- chical representations, which are suitable for fault classi- fication, directly from frequency distribution of the measurement data. The structure of the DBN model is investigated as the scale and depth of the DBN architecture directly affect its classification performance. Experimental study conducted on a machine fault simulator verifies the effectiveness of the deep learning approach for fault diagnosis of induction motors. This research proposes an intelligent diagnosis method for induction motor which utilizes deep learning model to automatically learn features from sensor data and realize working status recognition.

关键词： Fault diagnosis Deep learning Deep beliefnetwork. RBM Classification

First-principles calculations and experimental studies of Sn-Zn alloys as negative electrode materials for lithium-ion batteries

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Rare Metals 2011年第2期30卷 160-165页

作者： ru qiang PENG Wei ZHANG Zhiwen HU Shejun LI Yanling Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

The physical characters and electrochemical properties of various phases in a Sn-Zn electrode, such as formation energy, plateau potential, specific capacity, as well as volume expansion, were calculated by the first-principles plane-wave pseudo-potential method based on the den- sity functional theory. Sn-Zn films were also deposited on copper foils by an electroless plating technique. The actual composition and chemical characters were explored by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, plasma atomic emission spectrometry （ICP）, and constant current charge/discharge measurements （CC）. The results show that separation phases with tin and zinc including a small quantity of Cu6Sn5 phase were obtained, the initial lithium insertion capacity of the Sn-Zn film was 661 mAh/g, and obvious potential pla- teaus of about 0.4 V and 0.7 V were displayed, which is in accordance with the results of theoretical calculations. The capacity of the Sn-Zn film decreased seriously with the increase of cycle number.

关键词： lithium batteries electrochemical electrodes tin alloys first-principles calculations