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Robust Interval State Estimation for Distribution Systems Considering Pseudo-measurement Interval Prediction

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 179-188页

作者： xu Zhang Wei Yan Meiqing Huo Hui li the School of Electrical Engineering Chongqing UniversityChongqing 400044China

Interval state estimation(ISE)can estimate state intervals of power systems according to confidence intervals of predicted pseudo-measurements,thereby analyzing the impact of uncertain pseudo-measurements on states.However,predicted pseudo-measurements have prediction errors,and their confidence intervals do not necessarily contain the truth values,leading to estimation biases of the ISE.To solve this problem,this paper proposes a pseudo-measurement interval prediction framework based on the Gaussian process regression(GPR)model,thereby improving the prediction accuracy of pseudo-measurement confidence intervals.Besides,a weight assignment strategy for improving the robustness of weighted least squares(WLS)ISE is proposed.This strategy quantifies the deviation between the pseudo-measurement intervals and their estimated intervals and assigns smaller weights to the pseudo-measurement intervals with larger deviations,thereby improving the estimation accuracy and robustness of the ISE.This paper adopts the data from the supervisory control and data acquisition(SCADA)system of the New York Independent System Operator(NYISO).It verifies the advantages of the GPR method for pseudo-measurement interval prediction by comparing it with the quantile regression and neural network methods.In addition,this paper demonstrates the effectiveness of the proposed weight assignment strategy through the IEEE 14-bus case.Finally,the differences in the estimation accuracy and the bad data identification between the robust interval state estimation and deterministic state estimation are discussed.

关键词： Interval state estimation interval analysis pseudo-measurement Gaussian process regression(GPR)

IQABC-Based Hybrid Deployment Algorithm for Mobile Robotic Agents Providing Network Coverage

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Tsinghua Science and Technology 2024年第2期29卷 589-604页

作者： Shuang xu Xiaojie liu Dengao li Jumin Zhao College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyTaiyuan 030024China Pengcheng Laboratory Shenzhen 518055China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

Working as aerial base stations,mobile robotic agents can be formed as a wireless robotic network to provide network services for on-ground mobile devices in a target area.Herein,a challenging issue is how to deploy these mobile robotic agents to provide network services with good quality for more users,while considering the mobility of on-ground devices.In this paper,to solve this issue,we decouple the coverage problem into the vertical dimension and the horizontal dimension without any loss of optimization and introduce the network coverage model with maximum coverage range.Then,we propose a hybrid deployment algorithm based on the improved quick artificial bee colony.The algorithm is composed of a centralized deployment algorithm and a distributed one.The proposed deployment algorithm deploy a given number of mobile robotic agents to provide network services for the on-ground devices that are independent and identically distributed.Simulation results have demonstrated that the proposed algorithm deploys agents appropriately to cover more ground area and provide better coverage uniformity.

关键词： wireless robotic networks network coverage deployment algorithm improved quick artificial bee colony

β-Carboline alkaloids from the roots of Peganum harmala L.

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Chinese Journal of Natural Medicines 2024年第2期22卷 171-177页

作者： li Shengge ZHANG Qin WANG Yuetong liN Bin li Dahong HUA Huiming HU xu Henan Key Laboratory of Zhang Zhongjing Formulate and Herbs for Immunoregulation Zhang Zhongjing Traditional School of Chinese MedicineNanyang Institute of TechnologyNanyang 473004China Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationShenyang Pharmaceutical UniversityShenyang 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016China

This study reports the isolation of four newβ-carboline alkaloids(1−4)and six previously identified alkaloids(5−10)from the roots of Peganum harmala L.Among these compounds,1 and 2 were characterized as rareβ-carboline-quinazoline dimers exhibiting axial chirality.Compound 3 possessed a unique 6/5/6/7 tetracyclic ring system with an azepine ring,and compound 4 was a novel annomontineβ-carboline.The structures of these compounds were elucidated by spectroscopic data and quantum mechanical calculations.The biosynthetic pathways of 1−3 were proposed.Additionally,the cytotoxicity of some isolates against four cancer cell lines(HL-60,A549,MDA-MB-231,and DU145)was evaluated.Notably,compound 4 exhibited significant cytotoxicity against HL-60,A549,and DU145 cells with IC_(50) values of 12.39,12.80,and 30.65μmol·L^(−1),respectively.Furthermore,compound 2 demonstrated selective cytotoxicity against HL-60 cells with an IC_(50) value of 17.32μmol·L^(−1).

关键词： β-Carboline alkaloids Peganum harmala Structure elucidation Cytotoxic activity

Underwater inertial error rectification with limited acoustic observations

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Satellite Navigation 2024年第1期5卷 207-223页

作者： Hongqiong Tang Hongyang He Fangneng li Jiangning xu Department of Navigation Engineering Naval University of EngineeringWuhan430000China

Underwater inertial navigation is particularly difficult for the long-durance operations as many navigation systems such global satellite navigation systems are unavailable.The acoustic signal is a marvelous choice for underwater inertial error rectification due to its underwater penetration capability.However,the traditional Acoustic Positioning Systems(APS)are expensive and incapable of positioning with limited acoustic observations.Two novel underwater inertial error rectification algorithms with limited acoustic observations are proposed.The first one is the single acoustic-beacon Range-only Matching Aided Navigation(RMAN)method,which is inspired by matching navigation without reference maps and presented for the first time.The second is the improved single acoustic-beacon Virtual Long Baseline(VLBL)method,which considers the impact of indicated relative position increments on virtual beacon reconstruction.Both RMAN and improved VLBL are further developed when multi acoustic-beacons are available,named mAB-RMAN and mAB-VLBL.The comprehensive simulations and field investigations were conducted.The results demonstrated that the proposed methods achieved excellent accuracy and stability compared to the baseline,specifically,the mAB-RMAN and mAB-VLBL can reduce the inertial error by more than 90%and 98%when using single and double acoustic-beacons,respectively.These proposed techniques will provide new perspectives for underwater positioning,navigation,and timing.

关键词： Underwater PNT Range-only matching aided navigation Virtual long baseline Inertial error rectification

Predictive value of T cell receptor repertoire profiling for immunosuppressive therapy in severe aplastic anemia

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Genes & Diseases 2024年第1期11卷 95-98页

作者： Cunte Chen Yuling Zhang Dongpei Lu Zelong Zhang Jun Yang Xiaowei Chen Ming Zhou Wenjian Mo caixia Wang Qinghua cai Yumiao li Ruiqing Zhou Shilin xu Wei Zhou Tingfen Deng Shiyi Pan Yanli xu Shunqing Wang Yuping Zhang Department of Hematology Guangzhou First People's HospitalSouth China University of TechnologyGuangzhouGuangdong 510180China Guangzhou Junruikang Biotechnology Co. LtdGuangzhouGuangdong 510700China

Increasing evidence supports the hypothesis of autologous immune attack in severe aplastic anemia(SAA):the predominant role of activated cytotoxic T cells(CTL)expressing-interferon in inhibiting the growth of bone marrow(BM)cells,putative autoantigens,and oligoclonal expansion of CD8+T cells.1 For SAA patients,the definitive therapies are immunosuppressive therapy(IST)or hematopoietic stem transplantation(HSCT).

关键词： anemia aplastic interferon

Intracellular redox potential-driven live-cell synthesis of CdSe quantum dots in Staphylococcus aureus

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Science China Chemistry 2024年第3期67卷 990-999页

作者： cai-Qin Wu An-An liu xu li Jia-Wei Tu Juan Kong ling-ling Yang Jian-Hong Jia Chuan Wang Bin Hu Zhi-Xiong Xie Dai-Wen Pang The Institute for Advanced Studies College of Chemistry and Molecular SciencesCollege of Life SciencesHubei Key Laboratory of Cell HomeostasisWuhan UniversityWuhan 430072China Research Center for Analytical Sciences College of ChemistryState Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterFrontiers Science Center for Cell Responsesand Haihe Laboratory of Sustainable Chemical TransformationsNankai UniversityTianjin 300071China

Biosynthesized semiconductor quantum dots(QDs) have bright fluorescence,adjustable particle sizes,and environmental friendliness,endowing them with convenience and potential for biological applications.Due to the unclear mechanism of the cellular environment on the live-cell synthesis of QDs,it is still difficult to regulate their optical properties.Here,the critical role of the intracellular redox environment in regulating the fluorescence properties of biosynthesized CdSe QDs in Staphylococcus aureus(S.aureus) has been elucidated.The glutathione peroxidase(GPx) activity directly affects the intracellular H_(2)O_(2) produced in the SeO_(3)^(2-) reduction,which further manipulates the glutathione redox cycle to determine the content of low-valence Seintermediates.As a result,the fluorescence intensity of the synthesized CdSe QDs increases by 60% in the GPx overexpressed cells.The cellular redox potential that is controlled by the GSH redox cycle provides the driving force for the reduction of SeO_(3)^(2-),facilitating the synthesis of CdSe QDs in S.aureus cells.The proposed mechanism of the cellular redox state provides a new perspective for regulating the synthesis of semiconductor nanomaterials in live cells.

关键词： redox H_(2)O_(2) peroxidase quantum dot Staphylococcus aureus

Multiple paradoxical embolisms caused by central venous catheter thrombus passing through a patent foramen ovale: A case report

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World Journal of Clinical Cases 2024年第4期12卷 842-846页

作者： Jian-Duan li Nian xu Qiang Zhao Biao li li li Department of Cardiology Guangzhou Red Cross Hospital of Jinan UniversityGuangzhou 510235Guangdong ProvinceChina

BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent foramen ovale(PFO).CASE SUMMARY Here,we report a case of simultaneous coronary and lower limb artery embolism in a PFO patient carrier of a CVC.The patient presented to the hospital with acute chest pain and lower limb fatigue.Doppler ultrasound showed a large thrombus in the right internal jugular vein,precisely at the tip of the CVC.Transthoracic and transesophageal echocardiography confirmed the existence of a PFO,with inducible right-to-left shunting by the Valsalva maneuver.The patient was administered an extended course of anticoagulation therapy,and then the CVC was successfully removed.Percutaneous PFO closure was not undertaken.There was no recurrence during follow-up.CONCLUSION Thus,CVC-associated thrombosis is a potential source for multiple PDE in PFO patients.

关键词： Paradoxical embolism Central venous catheter Patent foramen ovale Acute myocardial infarction Case report

Diffraction limit of light in curved space

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Photonics Research 2024年第2期12卷 235-243页

作者： JINGxuAN ZHANG CHENNI xu PATRICK SEBBAH li-GANG WANG School of Physics Zhejiang UniversityHangzhou 310058China Department of Physics The Jack and Pearl Resnick Institute for Advanced TechnologyBar-Ilan UniversityRamat-Gan 5290002Israel

Overcoming the diffraction limit is crucial for obtaining high-resolution images and observing fine microstructures.With this conventional difficulty still puzzling us and the prosperous development of wave dynamics of light interacting with gravitational fields in recent years,how spatial curvature affects the diffraction limit is an attractive and important question.Here we investigate the issue of the diffraction limit and optical resolution on two-dimensional curved space—surfaces of revolution(SORs)with constant or variable spatial curvature.We show that the diffraction limit decreases and the resolution is improved on SORs with positive Gaussian curvature,opening a new avenue to super-resolution.The diffraction limit is also influenced by the propagation direction,as well as the propagation distance in curved space with variable spatial curvature.These results provide a possible method to control the optical resolution in curved space or equivalent waveguides with varying refractive index distribution and may allow one to detect the presence of the nonuniform strong gravitational effect by probing locally the optical resolution.

关键词： limit curved curvature

The role of proteasomes in tumorigenesis

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Genes & Diseases 2024年第4期11卷 155-169页

作者： Xiangyi Zhou Ruqing xu Yue Wu li Zhou Tingxiu Xiang Department of Oncology The First Affliated Hospital of Chongqing Medical UniversityChongqing 400016China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

Protein homeostasis is the basis of normal life activities,and the proteasomefamily plays an extremely important function in this process.The proteasome 2os is a concentric circle structure with twoαrings and twoβrings overlapped.The proteasome 2os can perform both ATP-dependent and non-ATP-dependent ubiquitination proteasome degradation by binding to various subunits(such as 19S,11S,and 200 PA),which is performed by its active subunitβ1,β2,andβ5.The proteasome can degrade misfolded,excess proteins tomaintain homeostasis.At the same time,it can be utilized by tumors to degrade over-proliferate and unwanted proteins to support their growth.Proteasomes can affect the development of tumors from several aspects including tumor signaling pathways such as NF-kB and p53,cell cycle,immune regulation,and drug resistance.Proteasome-encoding genes have been found to be overexpressed in a variety of tumors,providing a potential novel target for cancer therapy.In addition,proteasome inhibitors such as bortezomib,carfilzomib,and ixazomib have been put into clinical application as the first-line treatment of multiple myeloma.More and more studies have shown that it also has different therapeutic effects in other tumors such as hepatocellular carcinoma,non-small cell lung cancer,glioblastoma,and neuroblastoma.However,proteasome inhibitors are not much effective due to their tolerance and singleness in other tumors.Therefore,further studies on their mechanisms of action and drug interactions are needed to investigate their therapeutic potential.

关键词： Bortezomib Cancer therapy Immunoproteasome Multiplemyeloma Proteasome 20S Proteasome inhibitor Thymoproteasom