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Science China Chemistry 2018年第4期61卷 449-456页

作者： Bo Yu Peng Yang xiang gao Zhenzhen Yang Yanfei Zhao Hongye Zhang Zhimin Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Colloid Interface and Thermodynamics Institute of ChemistryChinese Academy of Sciences

CO_2 incorporation into C-H bonds is an important and interesting topic. Herein a sequential protocol for C(sp)-H carboxylation by employing a metal-free C-H activation/catalytic silylation reaction in conjunction with KO^tBu-mediated carboxylation with CO_2 was established, in which KO^t Bu catalyzes silylation of terminal alkynes to form alkynylsilanes at low temperature, and simultaneously mediates carboxylation of the alkynesilanes with atmospheric CO_2. Importantly, the carboxylation further promotes the silylation, which makes the whole reaction proceed very rapidly. Moreover, this methodology is simple and scalable, which is characterized by short reaction time, wide substrate scope, excellent functional-group tolerance and mild reaction conditions,affording a range of corresponding propiolic acid products in excellent yields in most cases. In addition, it also allows for a convenient ^(13)C-labeling through the use of ^(13)CO_2.

关键词： CO2 incorporation carboxylation propiolic acid KO^tBu C(sp)-H silylation

Experimental investigation of the detection and location of a target in layered media by using the TR-RTM mixed method

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Science China(Physics,Mechanics & Astronomy) 2019年第3期62卷 75-81页

作者： xiang gao Jian Li Jun Ma JunHong Li FangFang Shi Wen Wang ChengHao Wang Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences School of Electronic and Electrical Engineering Wuhan Textile University State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

Targets in layered media can be detected and located using a time reversal(TR)-reversed-time migration(RTM) mixed *** this study, this single emission-multiple receiving method is tested experimentally by using two types of layered media and three types of targets. The signal reflected at the interface and the signal scattered by the target are measured by each receiver to obtain the travel time for several transmitter-receiver pairs. Thereafter, the amplitude ratio between the two measured signals is compared with the theoretical amplitude. The RTM process involves the convolution of the forward acoustic beam from the source with the backward acoustic beam from the receiver which adds an appropriate delay determined on the measured travel time data. By using this approach, the acoustic field distribution can be obtained, and the position of the target can be ***, the measured positions of the target are compared with the actual position to validate the accuracy of this technique.

关键词： time reversal reversed-time migration ultrasonic detection layered media

Absorption Spectrum of a Driven Two-Level Atom in a Tunable Cavity with Injected Squeezed Vacuum

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Chinese Physics Letters 2000年第7期17卷 501-503页

作者： LI gao-xiang HUANG Guang-ming PENG Jin-sheng Department of Physics Huazhong Normal UniversityWuhan 430079

The absorption spectrum of a driven two-level atom in a frequency tunable cavity with injected squeezed vacuum is investigated. The line shape of the spectra depends on the relative phase between the driving field and the squeezed vacuum, and the frequency detuning between the driving field and the cavity mode. Line narrowing and probe gain can occur and be enhanced by adjusting the phase and detuning.

关键词： vacuum phase absorption

iTRAQ-based quantitative proteome characterization of wheat grains during filling stages

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Journal of Integrative Agriculture 2017年第10期16卷 2156-2167页

作者： CUI Yong YANG Ming-ming DONG Jian ZHAO Wan-chun gao xiang College of Agronomy Northwest A&F University Yangling 712100 P.R.China Wheat Engineering Research Center of Shaanxi Province Yangling 712100 P.R. China

Using isobaric tags for relative and absolute quantification （iTRAQ） and associated analytic technologies, we have cataloged and compared 7 069 unique wheat proteins expressed during four substages of the filling stage. Among them, 859 are differentially expressed, showing at least a 2-fold difference in concentration across substages. Differentially expressed proteins （DEPs） includind high-molecular weight giutenin subunit （W5AIU1）, low-molecular weight glutenin subunit （QSW3V4）, gliadin/avenin-like seed protein （D2KFG9）, and avenin-like protein （W5DVL2）, all of which have previously been identified as important for nutritional quality and bread-making properties, and all of which were found to increase at the latter stages of development. We have applied statistical techniques to group the proteins into hierarchical clusters, and have consulted databases to infer functional and other relationships among the identified proteins.

关键词： wheat proteome isobaric tags for relative and absolute quantification (iTRAQ) grain filling

Scleral buckling combined with internal cyclopexy for severe traumatic cyclodialysis cleft in open globe injuries

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International Journal of Ophthalmology(English edition) 2019年第10期12卷 1649-1653页

作者： Bo Chen gao-xiang Wang Xian Zhang Hong Yang Department of Ophthalmology Tongji HospitalTongjiMedical CollegeHuazhong University of Science andTechnologyWuhan430030Hubei ProvinceChina Department of Hematology Tongji HospitalTongji MedicalCollegeHuazhong University of Science and TechnologyWuhan430030Hubei ProvinceChina

This study aimed to evaluate the effect of scleral buckling combined with internal cyclopexy on the treatment of severe traumatic cyclodialysis cleft in open globe injuries(OGIS). This retrospective study recruited 10 patients of 10 eyes. With our surgical intervention, all the 10 eyes achieved retinal and ciliary body anatomic re-attachment. The choroidal ruptures in nine eyes were closed with complete choroidal reattachment. Postoperative best-corrected visual acuity of nine eyes had various improvements. The mean intraocular pressure was increased from 8.9±2.6 mm Hg to 13.4±4.4 mm Hg. Eventually, six eyes underwent silicone oil(SO) removal without complications, two eyes still had SO tamponade and two eyes became SO-dependent eyes. The result shows that internal direct cyclopexy combined with scleral buckling is an effective treatment for severe traumatic cyclodialysis cleft in OGIS.

关键词： cyclodialysis ocular trauma cyclopexy scleral buckling pars plana vitrectomy

Glucose metabolic abnormality is associated with defective mineral homeostasis in skeletal disorder mouse model

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Science China(Life Sciences) 2015年第4期58卷 359-367页

作者： ZOU JiangHuan XIONG XiWen LAI BeiBei SUN Min TU Xin gao xiang MOE Key Laboratory of Model Animal for Disease Study Model Animal Research Center Nanjing University

Bone was reported as a crucial organ for regulating glucose homeostasis. In this study, we found that Phex mutant mice(PUG), a model of human X-linked hypophosphatemic rickets(XLH), displayed metabolic abnormality in addition to abnormal phosphate homeostasis, skeletal deformity and growth retardation. Glucose tolerance was elevated with enhanced insulin sensitivity in PUG, though circulating insulin level decreased. Interestingly, bone mineral density defects and glucose metabolic abnormality were both rescued by adding phosphorus- and calcium-enriched supplements in daily diet. Serum insulin level, glucose tolerance and insulin sensitivity showed no differences between PUG and wild-type mice with rescued osteocalcin(OCN) following treatment. Our study suggested that OCN is a potential mediator between mineral homeostasis and glucose metabolism. This investigation brings a new perspective on glucose metabolism regulation through skeleton triggered mineral homeostasis and provides new clues in clinical therapeutics of potential metabolic disorders in XLH patients.

关键词： glucose metabolism mineral homeostasis bone Phex X-linked hypophosphatemic rickets

Multi-source data-based 3D digital preservation of large scale ancient chinese architecture:A case report

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Virtual Reality & Intelligent Hardware 2019年第5期1卷 525-541页

作者： xiang gao Hainan CUI Lingjie ZHU Tianxin SHI Shuhan SHEN National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The 3D digitalization and documentation of ancient Chinese architecture is challenging because of architectural complexity and structural *** generate complete and detailed models of this architecture,it is better to acquire,process,and fuse multi-source data instead of single-source *** this paper,we describe our work on 3D digital preservation of ancient Chinese architecture based on multi source *** first briefly introduce two surveyed ancient Chinese temples,Foguang Temple and Nanchan ***,we report the data acquisition equipment we used and the multi-source data we ***,we provide an overview of several applications we conducted based on the acquired data,including ground and aerial image fusion,image and LiDAR(light detection and ranging)data fusion,and architectural scene surface reconstruction and semantic *** believe that it is necessary to involve multi-source data for the 3D digital preservation of ancient Chinese architecture,and that the work in this paper will serve as a heuristic guideline for the related research communities.

关键词： Ancient Chinese architecture 3D digital preservation Multi-source data acquisition Architectural scene modeling

Protective effect of human umbilical cord mesenchymal stem cell-derived exosomes on rat retinal neurons in hyperglycemia through the brain-derived neurotrophic factor/TrkB pathway

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International Journal of Ophthalmology(English edition) 2021年第11期14卷 1683-1689页

作者： xiang gao Guang-Hui He Xiao-Tian Zhang Song Chen College of Medicine Nankai UniversityTianjin 300071China Tianjin Eye Hospital Tianjin 300020China Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300020China Ophthalmic Center of Xinjiang Production and Construction Corps Hospital Urumqi 830002Xinjiang Uygur Autonomous RegionChina

AIM:To explore whether human umbilical cord mesenchymal stem cell(hUCMSC)-derived exosomes(hUCMSC-Exos)protect rat retinal neurons in high-glucose(HG)conditions by activating the brain-derived neurotrophic factor(BDNF)-Trk B ***:h UCMSC-Exos were collected with differential ultracentrifugation methods and observed by transmission electron ***-linked immunosorbent assays(ELISAs)was used to quantify BDNF in hUCMSC-Exos,and Western blot was used to identify surface markers of *** retinal neurons were divided into 4 ***,cell viability,cell apoptosis,and TrkB protein expression were measured in retinal ***:hUCMSCs and isolated hUCMSC-Exos were successfully *** hUCMSC-Exos showed a diameter of 30 to 150 nm and had a phospholipid bimolecular membrane structure,as observed by transmission electron *** showed the BDNF concentration of hUCMSCs-Exos was 2483.16±***-Exos effectively reduced the apoptosis of retinal neuron rate and improved neuron survival rate,meanwhile,the results of immunofluorescence verified the fluorescence intensity of TrKB in neurons *** all above effects were reduced by treated hUCMSCs-Exos with BDNF ***-Exos effectively reduced the apoptosis rate of retinal neurons by activating the BDNF-TrkB pathway in a HG ***:In the HG environment,hUCMSC-Exos could carry BDNF into rat retinal neurons,inhibiting neuronal apoptosis by activating the BDNF-TrkB pathway.

关键词： human umbilical cord mesenchymal stem cells exosomes diabetic retin opathy retinal n euro ns BDNF-TrkB pathway

Experimental study of NO_2 reduction in N_2/Ar and O_2/Ar mixtures by pulsed corona discharge

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Journal of Environmental Sciences 2014年第11期26卷 2249-2256页

作者： Xinbo Zhu Chenghang Zheng xiang gao Xu Shen Zhihua Wang Zhongyang Luo Kefa Cen State Key Laboratory of Clean Energy Utilization Zhejiang University Zhejiang Electric Power Design Institute

Non-thermal plasma technology has been regarded as a promising alternative technology for NOx removal. The understanding of NO2 reduction characteristics is extremely important since NO2 reduction could lower the total NO oxidation rate in the plasma atmosphere. In this study, NO2 reduction was experimentally investigated using a non-thermal plasma reactor driven by a pulsed power supply for different simulated gas compositions and operating parameters. The NO2 reduction was promoted by increasing the specific energy density （SED）, and the highest conversion rates were 33.7%, 42.1% and 25.7% for Ar, N2/Ar and O2/Ar, respectively. For a given SED, the NO2 conversion rate had the order N2/Ar 〉 Ar 〉 02/Ar. The highest energy yield of 3.31 g/kWh was obtained in N2/Ar plasma and decreased with increasing SED; the same trends were also found in the other two gas compositions. The conversion rate decreased with increasing initial NO2 concentration. Furthermore, the presence of N2 or O2 led to different reaction pathways for NO2 conversion due to the formation of different dominating reactive radicals.

关键词： Non-thermal plasma Pulsed corona discharge NO NO2

A Differential Privacy Federated Learning Scheme Based on Adaptive Gaussian Noise

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1679-1694页

作者： Sanxiu Jiao Lecai Cai Xinjie Wang Kui Cheng xiang gao College of Automation and Information Engineering Sichuan University of Science and EngineeringYibin644000China Sanjiang Research Institute of Artificial Intelligence and Robotics Yibin UniversityYibin644000China College of Mechanical Engineering Sichuan University of Science and EngineeringYibin644000China

As a distributed machine learning method,federated learning(FL)has the advantage of naturally protecting data *** keeps data locally and trains local models through local data to protect the privacy of local *** federated learning method effectively solves the problem of artificial Smart data islands and privacy protection ***,existing research shows that attackersmay still steal user information by analyzing the parameters in the federated learning training process and the aggregation parameters on the server *** solve this problem,differential privacy(DP)techniques are widely used for privacy protection in federated ***,adding Gaussian noise perturbations to the data degrades the model learning *** address these issues,this paper proposes a differential privacy federated learning scheme based on adaptive Gaussian noise(DPFL-AGN).To protect the data privacy and security of the federated learning training process,adaptive Gaussian noise is specifically added in the training process to hide the real parameters uploaded by the *** addition,this paper proposes an adaptive noise reduction *** the convergence of the model,the Gaussian noise in the later stage of the federated learning training process is reduced *** paper conducts a series of simulation experiments on realMNIST and CIFAR-10 datasets,and the results show that the DPFL-AGN algorithmperforms better compared to the other algorithms.

关键词： Differential privacy federated learning deep learning data privacy