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Chinese Chemical Letters 2006年第7期17卷 953-956页

作者： Dan Dan HAN Chun WANG Zhi WANG Qiu Hua WU xiao huan zang College of Food Science and Technology Agricultural University of Hebei Baoding 071001 Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of HebeiBaoding 071001

A sensitive and simple micellar electrokinetic chromatography （MEKC） method was developed for the determination of antiepileptic drug, carbamazepine （CBZ）, using sweeping on-line concentration method with photodiode array detection. Under the optimal conditions, the calibration curve was linear over a range of 0.5-40μg·mL^-1 for CBZ with a correlation coefficient of 0.998. The detection limit （S/N = 3：1） of CBZ was 0.10 μg·mL^-1. The sweeping-MEKC method has been successfully applied to the analysis of CBZ in human serum.

关键词： On-line concentration carbarnazepine MEKC sweeping human serum.

Analysis of nitrobenzene compounds in water and soil samples by graphene composite-based solid-phase microextraction coupled with gas chromatography–mass spectrometry

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Chinese Chemical Letters 2014年第11期25卷 1449-1454页

作者： Gui-Jiang Zhang Xin Zhou xiao-huan zang Zhi Li Chun Wang Zhi Wang Department of Chemistry College of Science Agricultural University of Hebei

In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extraction material and its composite was coated on a stainless steel wire through sol–gel technique for the solid phase microextraction. The key parameters influencing the extraction efficiency were optimized. Under the optimal conditions, the linearity for the compounds was observed in the range of 0.02–15.0 mg/L for water samples, and 0.2–60.0 mg/kg for soil samples, with the correlation coefficients（r） of 0.9966–0.9987. The limits of detection of the method were 0.0025–0.005 mg/L for water samples, and 0.02–0.04 mg/kg for soil samples. The recoveries for the spiked samples were in the range of 72.0%–113.2%, and the precision, expressed as the relative standard deviations, was less than 12.1%.

关键词： Graphene Solid-phase microextraction Nitrobenzene compounds Gas chromatography–mass spectrometry

Combination of hollow fiber-based liquid-phase microextraction with sweeping techniques in micellar electrokinetic chromatography for the determination of Strychnos alkaloids in human urine

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Chinese Chemical Letters 2007年第3期18卷 316-318页

作者： xiao huan zang Cai Rui Li Qiu Hua Wu Chun Wang Dan Dan Han Zhi Wang Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China College of Vocational and Technological Sanitation Hebei University Baoding 071002 China

A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase microextxaodon （LPME） based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electrokinodc chromatography was developed. The calibration curve was linear over the range of 20-200 ng mL^-1 for both strychnine and brucine in human urine sample. The detection limits （S/N = 3：1） for strychnine and brucine were 1 ng mL^-1 and 2 ng mL^-1, respectively. The LPME-sweeping method has been successfully applied to the analysis of strychnine and brucine in real urine samples.

关键词： Hollow fiber-based liquid-phase microextraction Sweeping MEKC Strychnos alkaloids Urine

Numerical investigation on dynamic response of the screen mesh in vibrating screening through DEM-FEM co-simulation

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Particuology 2024年第4期87卷 205-217页

作者： huan Zhang xiao Zheng Weimin Jing Key Laboratory of MetallurgicalEquipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081 China Hubei Key Laboratory of Mechanical Transmssion and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044China

Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle level.Firstly,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen mesh.Then,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the co-simulation.Finally,the influence of screening parameters on LVA and its distribution was discussed.The results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.

关键词： Vibrating screen Dynamic response DEM-FEM Screening parameters Local vibration amplitude

New roles of tumor-derived exosomes in tumor microenvironment

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Chinese Journal of Cancer Research 2024年第2期36卷 151-166页

作者： Shiqian Chen Jinzhe Sun huan Zhou Hongbin Lei Dan zang Jun Chen Department of Oncology the Second Hospital of Dalian Medical UniversityDalian 116023China Department of Radiotherapy the Second Hospital of Dalian Medical UniversityDalian 116023China

Throughout tumorigenesis, the co-evolution of tumor cells and their surrounding microenvironment leads to the development of malignant phenotypes. Cellular communication within the tumor microenvironment(TME) plays a critical role in influencing various aspects of tumor progression, including invasion and metastasis. The release of exosomes, a type of extracellular vesicle, by most cell types in the body, is an essential mediator of intercellular communication. A growing body of research indicates that tumor-derived exosomes(TDEs) significantly expedite tumor progression through multiple mechanisms, inducing epithelial-mesenchymal transition and macrophage polarization, enhancing angiogenesis, and aiding in the immune evasion of tumor cells. Herein, we describe the formation and characteristics of the TME, and summarize the contents of TDEs and their diverse functions in modulating tumor development. Furthermore, we explore potential applications of TDEs in tumor diagnosis and treatment.

关键词： Tumor-derived exosomes tumorigenesis tumor microenvironment diagnosis treatment

Navigation Finsler metrics on a gradient Ricci soliton

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 266-275页

作者： LI Ying MO xiao-huan WANG xiao-yang Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral inequality.Then we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein type.As its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.

关键词： gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton

New clinical trial design in precision medicine:discovery,development and direction

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1293-1321页

作者： xiao-Peng Duan Bao-Dong Qin xiao-Dong Jiao Ke Liu Zhan Wang Yuan-Sheng zang Department of Medical Oncology Changzheng HospitalNaval Medical UniversityShanghaiChina

In the era of precision medicine,it has been increasingly recognized that individuals with a certain disease are complex and different from each other.Due to the underestimation of the significant heterogeneity across participants in traditional"one-sizefits-all"trials,patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket,umbrella,and platform trial designs under the master protocol framework.In recent years,the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous opportunities.Despite the rapid increase in the number of basket,umbrella,and platform trials,the current clinical and research understanding of these new trial designs,as compared with traditional trial designs,remains limited.The majority of the research focuses on methodologies,and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial designs.Therefore,we provide this comprehensive review of the discovery and development of basket,umbrella,and platform trials and their underlying logic from the perspective of precision medicine.Meanwhile,we discuss future directions on the potential development of these new clinical design in view of the"Precision Pro","Dynamic Precision",and"Intelligent Precision".This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic,which be essential to accelerate the progression of precision medicine.

关键词： clinical approval successive

Knockdown of neuronal DAF-15/Raptor promotes healthy aging in C.elegans

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Journal of Genetics and Genomics 2024年第5期51卷 507-516页

作者： xiao zang Qi Wang Hanxin Zhang Yiyan Zhang Zi Wang Zixing Wu Di Chen Model Animal Research Center of Medical School Nanjing UniversityNanjingJiangsu 210061China Zhejiang University-University of Edinburgh Institute School of MedicineZhejiang UniversityHainingZhejiang 314400China Department of Colorectal Surgery The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310058China

The highly conserved target of rapamycin(TOR)pathway plays an important role in aging across species.Previous studies have established that inhibition of the TOR complex 1(TORC1)significantly extends lifespan in Caenorhabditis elegans.However,it has not been clear whether TORC1 perturbation affects aging in a spatiotemporal manner.Here,we apply the auxin-inducible degradation tool to knock down endogenous DAF-15,the C.elegans ortholog of regulatory associated protein of TOR(Raptor),to characterize its roles in aging.Global or tissue-specific inhibition of DAF-15 during development results in various growth defects,whereas neuron-specific knockdown of DAF-15 during adulthood significantly extends lifespan and healthspan.The neuronal DAF-15 deficiency-induced longevity requires the intestinal activities of DAF-16/FOXO and PHA-4/FOXA transcription factors,as well as the AAK-2/AMP-activated protein kinaseαcatalytic subunit.Transcriptome profiling reveals that the neuronal DAF-15 knockdown promotes the expression of genes involved in protection.These findings define the tissue-specific roles of TORC1 in healthy aging and highlight the importance of neuronal modulation of aging.

关键词： Aging targetof rapamycin DAF-15 DAF-16 C.elegans

Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography

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Chinese Chemical Letters 2009年第2期20卷 213-216页

作者： Zhi Mei Liu xiao huan zang Wei Hua Liu Chun Wang Zhi Wang Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

A novel method for the determination of five carbamate pesticides （metolcarb, carbofuran, carbaryl, isoprocard and diethofencard） in water samples was developed by dispersive liquid-liquid microextraction （DLLME） coupled with high performance liquid chromatography-diode array detector （HPLC-DAD）. Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients （r^2） varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection （LODs）（S/N = 3） were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples.

关键词： Carbamate pesticides High performance liquid chromatography Diode array detection Dispersive liquid-liquid microextraction Water samples

Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai huan Li xiao Tang Ruonan Zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum efficiency.To tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded cell.To fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent cells.To tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV position.Then,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation schemes.We further propose an iterative power allocation algorithm based on the sequential convex approximation theory.The simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management