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Portable fluorogenic probe for monitoring of volatile amine vapour and food spoilage

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Chinese Chemical Letters 2024年第3期35卷 257-261页

作者： Jian-Hao Zhao Wen-Xing xu Bin Li Wei xu Wu-Kun Zhang Ming-Shuai Yuan Hui-Zi Li qing-Guo He Xiang Ma Jian-Gong Cheng yan-yan Fu State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of the Chinese Academy of SciencesBeijing 100039China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

There are urgent needs of volatile amine gas sensors with high-performance in food quality control,disease monitoring and environmental pollution.Thin-film fluorescent probe is suitable for amine vapour sensing due to its high sensitivity,high selectivity,and no polluting analyte.Herein,a novel fluorescent probe based on indacenodithiophene structure withπconjugated system was designed and synthesized.The experimental results show that the films prepared by this material exhibit rapid and distinct fluorescence quenching after being exposed to saturated vapours of primary amine,secondary amine and tertiary amine represented by n-propylamine,diethylamine and trimethylamine,respectively.The quenching of fluorescence is 84%,87%and 96%,respectively,within 10 s.The detection mechanism of probe for primary amine is based on specific chemical reaction,while the detection mechanism for secondary amine and tertiary amine is intramolecular charge transfer.Further experiments show that the detection limit of the fluorescent probe for trimethylamine,an important marker of food spoilage,could reach 4.610 ppt.On-site detection based on spoilage of small yellow croaker suggests the material possesses the potential for food freshness detection.This simple fluorogenic probe is an original approach to simplify real-time visual monitoring of volatile amine vapour.

关键词： Fluorescent probe Volatile amine Gas sensing Trimethylamine Food spoilage

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-Xi Zhang Kai-Di xu qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients

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World Journal of Gastroenterology 2024年第23期30卷 3005-3015页

作者： yan-Fen xu Hui-Yun Ma Gui-Ling Huang Yu-Ting Zhang xue-yan Wang Ming-Jie Wei Xiao-qing Pei Department of Ultrasound State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina Department of Radiology State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina Department of Medical Ultrasound State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina

BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.

关键词： Double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging

Emerging non-antibody‒drug conjugates (non-ADCs) therapeutics of toxins for cancer treatment

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1542-1559页

作者： Xiaolan xu Jiaming Zhang Tao Wang Jing Li Yukang Rong yanfang Wang Chenxia Bai qing yan Xiaohua Ran Yingli Wang Tianhong Zhang Jin Sun Qikun Jiang Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China School of Education University of NottinghamNottingham NG72RDUK Department of Pharmacy Linyi People's HospitalShandong UniversityLinyi 276000China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100871China

The non-selective cytotoxicity of toxins limits the clinical relevance of the toxins.In recent years,toxins have been widely used as warheads for antibody-drug conjugates(ADCs)due to their eff-cient killing activity against various cancer cells.Although ADCs confer certain targeting properties to the toxins,low drug loading capacity,possible immunogenicity,and other drawbacks also limit the po-tential application of ADCs.Recently,non-ADC delivery strategies for toxins have been extensively investigated.To further understand the application of toxins in anti-tumor,this paper provided an over-view of prodrugs,nanodrug delivery systems,and biomimetic drug delivery systems.In addition,toxins and their combination strategies with other therapies were discussed.Finally,the prospect and challenge of toxins in cancertreatmentwerealso summarized.

关键词： Toxins Non-antibody-drug conjugates Delivery strategies Prodrugs Nano drug delivery systems Biomimetic drugdelivery systems Combination strategies Cancer treatment

Design and synthesis of hybrid solids based on the tetravanadate core toward improved catalytic properties

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Chinese Chemical Letters 2016年第5期27卷 649-654页

作者： yan-Hong Niu Song yang Ji-Kun Li yan-qing xu Chang-Wen Hu Key Laboratory of Cluster Science Ministry of Education of China Beijing Key Laboratory of PhotoelectronicElectrophotonic School of Chemistry Beijing Institute of Technology

Five inorganic-organic hybrid vanadates based on tetravanadate cores, transition metals and N-donor ligands have been designed and synthesized under hydrothermal conditions, namely, [Zn（elM）312V4O12 （1）, [Zn（plM）3]2V4O12.H2O （2）, [Zn（iplM）3]2V4O12 （3）, [Co（eIM）3]2V4O12.H2o （4）, [Cu（eIM）2（H20）]2V4O12 （5）（eIM = 1-ethylimidazole, plM = 1-propylimidazole, ipIM = isopropylimidazole）. All compounds were fully characterized by single-crystal XRD, powder XRD, elemental analysis, TGA, and FT-IR spectroscopy. The hybrid zinc vanadates （1-3） and cobalt vanadate （4） exhibit interesting 2D folded structures and the hybrid copper vanadate （5） presents a 1D chain configuration. All compounds can catalyze olefin epoxidation reactions when using TBHP （TBHP = tert-butyl hydroperoxide） as an oxidant in acetonitrile. The introduction of transition metal ions into tetravanadate cores not only improved the catalytic activity but also fulfilled the heterogeneous catalytic behavior. 1-5 all exhibit extraordinary efficiency in converting olefins to the corresponding epoxides with high conversion and selectivity （particularly, cony. up to 97.1%, sele. up to 100% for 1 ）. Leaching test was also carried out to prove the heterogeneous behavior.

关键词： Hybrid Tetrvanadate core Heterogeneous catalysts Olefin epoxidation

Identifying the geographical origin and processing technology of Moyao(Myrrh) on the basis of near-infrared spectroscopy combined with chemometrics

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Journal of Traditional Chinese Medicine 2024年第3期44卷 505-514页

作者： xu Ningning yan Ganming xu Fengjie DENG Linfeng QIAO Xinjiang LU Changzheng CHENG Shaomin TCM Diagnosis Institute College of Traditional Chinese MedicineJiangxi University of Chinese Medicine TCM Processing Institute Pharmaceutical CollegeJiangxi University of Chinese medicine School of Electronic Information and Artificial Intelligence Shaanxi University of Science and Technology Jiangzhong Pharmaceutical Co. Ltd. Jiangxi Guhan Refined Chinese Herbal Pieces Co. Ltd.

OBJECTIVE: To evaluate the quality of Moyao(Myrrh) in the identification of the geographical origin and processing of the products. METHODS: Raw Moyao(Myrrh) and two kinds of Moyao(Myrrh) processed with vinegar from three countries were identified using near-infrared(NIR) spectroscopy combined with chemometric techniques. Principal component analysis(PCA) was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories. A classical chemometric algorithm(PLS-DA) and two machine learning algorithms [K-nearest neighbor(KNN) and support vector machine] were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh) samples, and their discriminative performance was evaluated. RESULTS: Based on the accuracy, precision, recall rate, and F1 value in each model, the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive results. In all of the chemometric analyses, the NIR spectrum of Moyao(Myrrh) preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins, and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the best. The best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 respectively. CONCLUSIONS: NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh) and can also provide a reference for evaluations of its quality and the clinical use.

关键词： Moyao () geographical origin near-infrared spectroscopy processing technology

Initial experience with circumferential pulmonary vein isolation guided~ by Overlay Ref and CartoMerge in the treatment of paroxysmal atrial fibrillation

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Chinese Medical Journal 2010年第10期123卷 1269-1272页

作者： TANG Kai ZHAO Dong-dong ZHANG Jing-ying CHEN yan-qing xu Ya-wei Department of Cardiology Shanghai Tenth People's Hospital Tong Ji University Shanghai 200072 China

Background CartoMerge has been widely used in guiding circumferential pulmonary vein isolation （CPVI） for the treatment of paroxysmal atrial fibrillation （PAF）. However, the procedure of landmarks selection varies among operators according to their experience. Techniques have to be established to standardize this procedure. We propose that Overlay Ref could facilitate this procedure. This paper aimed to report our initial experience with CPVI guided by Overlay Ref and CartoMerge for the treatment of PAF. Methods Fifty-nine patients with PAF were enrolled in this study. Using Overlay Ref technique, a reference image （inverted） was faded into the live fluoroscopic image. Landmarks of CartoMerge were selected from anatomic points of the top of superior pulmonary veins （PVs） and the bottom of inferior PVs guided by Overlay Ref image. Overlay Ref images were also used to guide the ablation procedure combining with CartoMerge. Results All patients were successfully mapped by CartoMerge guided by Overlay Ref. The distance between the mapping points and the CT surfaces was （1.42±0.67） mm for the patients as a whole. This led to a successful rate of 96% for isolation of pulmonary veins. Duration of ablation procedure was （92±17） minutes. And the total duration of procedure was （139±32） minutes. CartoMerge could also be performed just with 3 paries to 4 paries selected landmarks guided by Overlay Ref without a full anatomic model constructed by Carto. Then, the total duration of procedure could be shortened to （115±38） minutes. Conclusions Overlay Ref technique can facilitate the catheter ablation of PAF and can help to standardize the procedure of landmarks selection.

关键词： circumferential pulmonary vein isolation Overlay Ref technique computed tomography three-dimensional electroanatomic mapping atrial fibrillation

Random gradient-free method for online distributed optimization with strongly pseudoconvex cost functions

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Control Theory and Technology 2024年第1期22卷 14-24页

作者： Xiaoxi yan Cheng Li Kaihong Lu Hang xu School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao266590ShandongChina

This paper focuses on the online distributed optimization problem based on multi-agent systems. In this problem, each agent can only access its own cost function and a convex set, and can only exchange local state information with its current neighbors through a time-varying digraph. In addition, the agents do not have access to the information about the current cost functions until decisions are made. Different from most existing works on online distributed optimization, here we consider the case where the cost functions are strongly pseudoconvex and real gradients of the cost functions are not available. To handle this problem, a random gradient-free online distributed algorithm involving the multi-point gradient estimator is proposed. Of particular interest is that under the proposed algorithm, each agent only uses the estimation information of gradients instead of the real gradient information to make decisions. The dynamic regret is employed to measure the proposed algorithm. We prove that if the cumulative deviation of the minimizer sequence grows within a certain rate, then the expectation of dynamic regret increases sublinearly. Finally, a simulation example is given to corroborate the validity of our results.

关键词： Multi-agent system Online distributed optimization Pseudoconvex optimization Random gradient-free method

Enhanced corrosion resistance of epoxy resin coating via addition of CeO_(2) and benzotriazole

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Chinese Journal of Chemical Engineering 2024年第3期67卷 89-96页

作者： xu Han Ruijie Guo Baolong Niu Hong yan College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

The use of fillers to enhance the corrosion protection of epoxy resins has been widely applied.In this work,cerium dioxide(CeO_(2))and benzotriazole(BTA)were introduced into an epoxy resin to enhance the corrosion resistance of Q235 carbon steel.Scanning electron microscopy results indicated that the CeO_(2) grains were rod-like and ellipsoidal in shape,and the distribution pattern of BTA was analyzed by energy dispersive spectroscope.The dynamic potential polarization curve proved the excellent corrosion resistance of the composite epoxy resin with CeO_(2) and BTA co-addition,and electrochemical impedance spectroscopy test analysis indicated the significantly enhanced long-term corrosion protection performance of the composite coating.And the optimal protective performance was provided by the coating containing 0.3%(mass)CeO_(2) and 20%(mass)BTA,which was attributed to the barrier performance of CeO_(2) particles and the chemical barrier effect of BTA.The formation of corrosion products was analyzed using X-ray diffraction.In addition,the corrosion resistance mechanism of the coating was also discussed in detail.

关键词： Benzotriazole Cerium dioxide Corrosion resistance Carbon steel Epoxy resin coating Preparation