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Modeling of cascaded high isolation bidirectional amplification in long-distance fiber-optic time and frequency synchronization system

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Chinese Physics B 2021年第7期30卷 294-302页

作者： Kuan-Lin Mu xing chen zheng-Kang Wang Yao-Jun Qiao Song Yu The State Key Laboratory of Information Photonics and Optical Communications School of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

We propose a physical model of estimating noise and asymmetry brought by high isolation Bi-directional erbiumdoped fiber amplifiers(Bi-EDFAs),no spontaneous lasing even with high gain,in longdistance fiber-optic time and frequency(T/F)synchronization *** is found that the Rayleigh scattering noise can be suppressed due to the high isolation design,but the amplified spontaneous emission(ASE)noise generated by the high isolation Bi-EDFA and the bidirectional asymmetry of the transmission link caused by the high isolation Bi-EDFA will deteriorate the stability of the *** calculated results show that under the influence of ASE noise,the frequency instability of a 1200 km system composed of 15 high isolation Bi-EDFAs is 1.773×10^(-13)/1 *** the instability caused by asymmetry is 2.6064×10^(-16)/30000–35000 s if the total asymmetric length of the bidirectional link length is 30 *** intensity noises originating from the laser and detector,the transfer delay fluctuations caused by the variation in ambient temperature and the jitter in laser output wavelength are also *** experiment composed of three high isolation Bi-EDFAs is done to confirm the theoretical *** summary,the paper shows that the short-term instability of the T/F synchronization system composed of high isolation Bi-EDFAs is limited by the accumulation of ASE noise of amplifiers and the laser frequency drift,while the long-term instability is limited by the periodic variation in ambient temperature and the asymmetry of the *** research results are useful for pointing out the direction to improve the stability of the fiber-optic T/F synchronization system.

关键词： time and frequency synchronization erbium-doped fiber amplifier instability Allan deviation

Microwave-assisted synthesis of α-hydroxy aromatic ketones from α-bromo aromatic ketones in water

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Chinese Chemical Letters 2011年第1期22卷 53-56页

作者： Xiang Liu Hai Bo chen zheng Guang Pan Jian He Xu He xing Li School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai 200237 China Department of Chemistry Shanghai Normal University Shanghai 200234 China

A reaction of α-bromo aromatic ketones in water with microwave irradiation gave the corresponding α-hydroxy aromatic ketones in good yields. The use of microwaves was found to significantly improve yields and shorten the reaction time. This reaction afforded a very clean, convenient method for the synthesis of α-hydroxy aromatic ketones.

关键词： α-Hydroxy aromatic ketones α-Bromo aromatic ketones Microwave irradiation

BP neural network model for material distribution prediction based on variable amplitude anti-blocking screening DEM simulations

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 190-199页

作者： zheng Ma Yongle Zhu Zhiping Wu Souleymane Nfamoussa Traore Du chen Licheng xing School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory of Modern Agricultural Equipment and Technology Ministry of Education&Jiangsu ProvinceJiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory for Theory and Technology of Intelligent Agricultural Machinery and Equipment Jiangsu UniversityZhenjiang 212013JiangsuChina College of Engineering China Agricultural UniversityBeijing 100083China Jiangsu World Agricultural Machinery Co. Ltd.Picheng Industrial ParkDanyang 212311JiangsuChina

The material feeding changing of combine harvester is easy to cause accumulation and blockage of the vibrating screen,which seriously affects the harvest *** order to alleviate such accumulation and blockages on the vibrating screen surface,the guide chute rotation angle of the improved variable amplitude screening mechanism was selected as the target variable,and EDEM-RecurDyn was employed to simulate the anti-blocking process of the variable amplitude under a changing feeding quantity(0.5 kg/s abnormal,0.2 kg/s normal)of materials(rice grain and stem mixture).A BP(an error back propagation algorithm)neural network was designed and the prediction model of the material distribution was subsequently constructed on the variable screening surface under different chute angles during abnormal *** results revealed a continuous decrease in the quality and time of the material blockage at the front end of the screen surface with the increasing guide chute *** the guide chute angle of 20°-45°and adjustment time of 3-6 s,the blocked and accumulated materials at the front-end screen surface was be moved back to Grid 6 for ***,overtime,the screen surface materials continued to move back under the chute angle of 40°-45°,which had a great impact on the screening *** the guide chute angle of 30°-35°and adjustment time of 4 s,the materials on the screen surface were evenly distributed in Grid *** was able to alleviate the accumulation and blockage of the screen surface *** R of the material distribution prediction model(BP neural network)on the screen surface was determined as 0.97,indicating the high reliability and accuracy of the material distribution model on the screen surface based on the BP neural *** work provides an important reference for the variable amplitude intelligent control of screen surface material anti-blocking.

关键词： variable amplitude material distribution EDEM-RecurDyn BP neural network

Structure-guided engineering of transcriptional activator XYR1 for inducer-free production of lignocellulolytic enzymes in Trichoderma reesei

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Synthetic and Systems Biotechnology 2023年第4期8卷 732-740页

作者： Qinqin Zhao Zezheng Yang Ziyang Xiao zheng Zhang Jing xing Huiqi Liang Liwei Gao Jian Zhao Yinbo qu Guodong Liu State Key Laboratory of Microbial Technology Shandong UniversityQingdao266237China Taishan College Shandong UniversityQingdao266237China Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao266101China

The filamentous fungus Trichoderma reesei is widely used for the production of lignocellulolytic enzymes in ***1 is the major transcriptional activator of cellulases and hemicellulases in ***,rational engineering of XYR1 for improved lignocellulolytic enzymes production has been limited by the lack of structure ***,alanine 873 was identified as a new potential target for the engineering of XYR1 based on its structure predicted by *** mutation of this residue to tyrosine enabled significantly enhanced production of xylanolytic enzymes in the medium with cellulose as the carbon ***,xylanase and cellulase production increased by 56.7-and 3.3-fold,respectively,when glucose was used as the sole carbon *** both conditions,the improvements of lignocellulolytic enzyme production were higher than those in the previously reported V821F *** the enriched hemicellulases and cellulases,the crude enzymes secreted by the A873Y mutant strain produced 51%more glucose and 52%more xylose from pretreated corn stover than those of the parent *** results provide a novel strategy for engineering the lignocellulolytic enzyme-producing capacity of ***,and would be helpful for understanding the molecular mechanisms of XYR1 regulation.

关键词： Xylanase Cellulase Trichoderma reesei Transcription factor Genome editing

Performance of a plastic scintillation fiber dosimeter based on different photoelectric devices

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Nuclear Science and Techniques 2021年第11期32卷 25-31页

作者： Yue Yang Cui-Ping Yang Jie Xin Hai-Feng chen Zhong-Xu xing Wei-Wei qu Liang Hu Xin-Jian chen Ren-Sheng Wang State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China Renji Hospital Affiliated with the Shanghai Jiao Tong University School of MedicineShanghai 200127China Shanghai Ninth People’s Hospital Affiliated with the Shanghai Jiao Tong University School of MedicineShanghai 200127China Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Suzhou 215123China

The photoelectric device of a scintillation dosimeter converts photons produced by radiation into an electrical *** features directly determine the overall performance of the *** a plastic scintillation fiber dosimeter(PSFD)with a current readout mode,systematic studies of the stability and light-dose response were performed for the photomultiplier tube(PMT),silicon photomultiplier(SiPM),avalanche photodiode(APD),and photodiode(PD).The temperature stability,long-term stability,repeatability,signal-to-noise ratio(SNR),and current dose response of the PSFD with the abovementioned photoelectric devices were studied using a pulsed LED light source and the Small Animal Radiation Therapy *** exponential relationship between the dark/ne current and temperature was obtained for all the devices.I is shown that the APD is the most sensitive device to temperature,with a current dependence on temperature reaching 6.5%C^(-1)at room temperature,whereas for the other devices this dependence is always<0:6%C^(-1).In terms of long-term stability,the net current of PD can change by up to 4%when working continuously for 8 h and 2%when working intermittently for 32 h,whereas for the other devices,the changes are all<1%.For the dose response,the PMT and SiPM exhibit excellent linear responses and SNRs within the range of 0.1-60 Gy/min For the PSFD with a current readout mode,the performance of the PMT and SiPM is concluded to be better than that of the other devices in the *** particular,the SiPM,which has a compact size,low bias voltage,and antimagnetic interference,has great advantages for further applications.

关键词： Photoelectric device Plastic scintillation fiber dosimeter(PSFD) Current readout Dose response

Improved sensing performance of WO_(3) nanoparticles decorated with Ag and Pt nanoparticles

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Rare Metals 2021年第6期40卷 1642-1650页

作者： Dong-Liang Feng zheng-You Zhu Ling-Ling Du Xia-Xia xing chen Wang Jian chen Yong-Tao Tian Da-Chi Yang Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology and Department of ElectronicsCollege of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China School of Physics and Engineering and Key Laboratory of Materials Physics Ministry of EducationZhengzhou UniversityZhengzhou 450001China

Gas sensors built with metal oxide semiconductors have attracted tremendous attention due to the growing demand for the detection of inflammable,explosive and toxic ***,to improve the sensing response,WO_(3) nanoparticles decorated with Ag and Pt bimetals(Ag and Pt/WO_(3) NPs)have been developed via combined hydrolysis and hydrothermal *** sensors prototypes show high response to acetone(Ra/Rg=250@100×10^(-6),140℃),which is 6.1 fold as high as that of the pristine WO_(3) NPs(Ra/Rg=41@100×10^(-6),140℃).Moreover,the recovery time of Ag and Pt/WO_(3) NPs was reduced from 138 to 13 s compared with that of the pristine WO_(3) *** improved acetone sensing performance may be attributed to that the chemical and electronic sensitization of Ag and Pt to WO_(3) NPs increases adsorbed oxygen species,speeds up the reaction and thus boosts the sensing *** strategy that decoration of dual precious metals onto WO_(3) NPs improves the acetone sensing performance may be applied to the gas sensors of other sensing materials.

关键词： WO_(3)nanoparticles Ag and Pt bimetals Acetone sensing Chemical sensitization Recovery time

Re-expression of DIRAS3 and P53 induces apoptosis and impaired autophagy in head and neck squamous cell carcinoma

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Military Medical Research 2021年第2期8卷 148-161页

作者： Zhe Liu Douglas R.Hurst xing qu Li-Guang Lu chen-Zhou Wu Yu-Yu Li Yi Li State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041China Department of Head and Neck Oncology West China Hospital of StomatologySichuan UniversityChengdu 610041China Department of Pathology University of Alabama at BirminghamBirminghamAL 35216USA Department of Evidence Based Stomatology West China Hospital of StomatologySichuan UniversityChengdu 610041China.

Background:p53 and DIRAS3 are tumor suppressors that are frequently silenced in *** this study,we sought to determine whether the concurrent re-expression of p53 and DIRAS3 could effectively induce head and neck squamous cell carcinoma(HNSCC)cell ***:CAL-27 and SCC-25 cells were treated with Ad-DIRAS3 and rAd-p53 to induce re-expression of DIRAS3 and p53 *** effects of DIRAS3 and p53 re-expression on the growth and apoptosis of HNSCC cells were examined by TUNEL assay,flow cytometric analysis and *** effects of DIRAS3 and p53 re-expression on Akt phosphorylation,oncogene expression,and the interaction of 4 E-BP1 with eIF4 E were determined by real-time PCR,Western blotting and immunoprecipitation *** ability of DIRAS3 and p53 re-expression to induce autophagy was evaluated by transmission electron microscopy,LC3 fluorescence microscopy and Western *** effects of DIRAS3 and p53 re-expression on HNSCC growth were evaluated by using an orthotopic xenograft mouse ***:TUNEL assay and flow cytometric analysis showed that the concurrent re-expression of DIRAS3 and p53 significantly induced apoptosis(P<0.001).MTT and flow cytometric analysis revealed that DIRAS3 and p53 reexpression significantly inhibited proliferation and induced cell cycle arrest(P<0.001).Mechanistically,the concurrent re-expression of DIRAS3 and p53 down-regulated signal transducer and activation of transcription 3(STAT3)and upregulated p21WAF1/CIP1 and Bax(P<0.001).DIRAS3 and p53 re-expression also inhibited Akt phosphorylation,increased the interaction of eIF4 E with 4 E-BP1,and reduced the expression of c-Myc,cyclin D1,vascular endothelial growth factor(VEGF),fibroblast growth factor(FGF),epidermal growth factor receptor(EGFR)and Bcl-2(P<0.001).Moreover,the concurrent re-expression of DIRAS3 and p53 increased the percentage of cells with GFP-LC3 puncta compared with that in cells treated with control adenovirus(50.00%±4.55%vs.4.67%±1.25%,P<

关键词： DIRAS3 p53 Apoptosis Autophagy Head and neck squamous cell carcinoma

Recyclability and Self-Healing of Dynamic Cross-Linked Polyimide with Mechanical/Electrical Damage

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Energy & Environmental Materials 2023年第1期6卷 401-407页

作者： Baoquan Wan Ming-Sheng zheng xing Yang Xiaodi Dong Yuchao Li Yiu-Wing Mai George chen Jun-Wei Zha School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing 100083China Shunde Graduate School of University of Science and Technology Beijing Foshan 528300China School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China Centre for Advanced Materials Technology(CAMT) School of AerospaceMechanical and Mechatronic EngineeringThe University of SydneySydney New South Wales 2006Australia Department of Electronics and Computer Science University of SouthamptonSouthampton SO171BJUK

Recyclability and self-healing are two most critical factors in developing sustainable polymers to deal with environmental pollution and resource *** this work,a dynamic cross-linked polyimide insulation film with full closed-loop recyclability is successfully prepared,which also possesses good self-healing ability after being mechanical/electrical damaged depending on the Schiff base dynamic covalent *** recycled and self-healed polyimide film still maintain its good tensile strength(r t)>60 MPa with Young’s modulus(E)>4 GPa,high thermal stability with glass transition temperature(T g)>220℃,and outstanding insulation property with breakdown strength(E 0)>358 kV mm^(-1),making it a very promising low energy consumption and high temperature resistant insulation *** strategy of using Schiff base dynamic covalent bonds for reversible repairing the structure of high T g polyimides promotes the wider application of such sustainable and recyclable material in the field of electrical power and micro-electronics.

关键词： electrical damage polyimide recyclability self-healing

BOD1 regulates the cerebellar IV/V lobe-fastigial nucleus circuit associated with motor coordination

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2490-2503页

作者： Xiu-Xiu Liu xing-Hui chen Zhi-Wei zheng Qin Jiang chen Li Lin Yang Xiang chen xing-Feng Mao Hao-Yang Yuan Li-Li Feng quan Jiang Wei-xing Shi Takuya Sasaki Kohji Fukunaga Zhong chen Feng Han Ying-Mei Lu Key Laboratory of Cardiovascular&Cerebrovascular Medicine Drug Target and Drug Discovery CenterSchool of PharmacyNanjing Medical University211166 NanjingChina Department of Physiology School of Basic Medical SciencesNanjing Medical University211166 NanjingChina Institute of Pharmacology and Toxicology College of Pharmaceutical SciencesZhejiang University310058 HangzhouChina Department of Pharmaceutical and Administrative Sciences Loma Linda University School of PharmacyLoma LindaCA 92350USA Department of Basic Sciences Loma Linda University School of MedicineLoma LindaCA 92350USA Department of Pharmacology Graduate School of Pharmaceutical SciencesTohoku UniversitySendai 980-8578Japan Institute of Brain Science the Affiliated Brain Hospital of Nanjing Medical University210029 NanjingChina Gusu School Nanjing Medical UniversitySuzhou Municipal HospitalThe Affiliated Suzhou Hospital of Nanjing Medical University215002 SuzhouChina

Cerebellar ataxias are characterized by a progressive decline in motor coordination,but the specific output circuits and underlying pathological mechanism remain poorly *** cell-type-specific manipulations,we discovered a novel GABAergic Purkinje cell(PC)circuit in the cerebellar IV/V lobe that projected to CaMKIIα+neurons in the fastigial nucleus(FN),which regulated sensorimotor ***,transcriptomics profiling analysis revealed various cerebellar neuronal identities,and we validated that biorientation defective 1(BOD1)played an important role in the circuit of IV/V lobe to ***1 deficit in PCs of IV/V lobe attenuated the excitability and spine density of PCs,accompany with ataxia ***,BOD1 enrichment in PCs of IV/V lobe reversed the hyperexcitability of CaMKIIα+neurons in the FN and ameliorated ataxia behaviors in L7-Cre;BOD1f/f ***,these findings further suggest that specific regulation of the cerebellar IV/V lobePCs→FNCaMKIIα+circuit might provide neuromodulatory targets for the treatment of ataxia behaviors.

关键词： fastigial reversed Together