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Stability and performance analysis of the compressed Kalman filter algorithm for sparse stochastic systems

Science China(Technological Sciences) 2024年第2期67卷 380-394页

作者： li RongJiang GAN die XIE SiYu LüJinHu Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun Laboratory Beijing 100049China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic *** deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)*** algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional ***,the original high-dimensional sparse signals can be well recovered by a reconstruction *** ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and ***,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.

关键词： sparse signal compressed sensing Kalman filter algorithm compressed excitation condition stochastic stability tracking performance

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How mutual funds respond to asymmetric feedback tradingin China’s stock market

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Journal of Management Science and Engineering 2024年第2期9卷 143-160页

作者： die Wan li Yang Xiaoguang Yang School of Finance Zhejiang Gongshang UniversityHangzhou310018China Business School University of New South WalesSydneyAustralia Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijingChina

Previous studies show that individual investors play a dominant role in China's stock *** behavior of chasing-rise being stronger than killing-fall leads to asymmetry of feedback *** article investigates how mutual funds react to this market *** China's stock and fund data from 2003 to 2019,we find that mutual funds tend to hold fewer shares when asymmetric feedback trading of the relevant stock gets more *** negative relationship is robust after controlling past returns,turnover rates,and firm risk factors,moreover,it attenuates when the market sentiment is bullish or when stocks are allowed *** results show that mutual funds'selling towards asymmetric feedback trading does not make excess return but leads to significant risk *** findings may be related to uncertainty associated with asymmetric feedback trading,and thus support the limit market participation theory from the second largest stock market.

关键词： Asymmetric feedback trading Mutual fund shareholdings Uncertainty Market sentiment Short selling

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Nanoparticle delivery for central nervous system diseases and its clinical application

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Nano Research 2024年第7期17卷 6305-6322页

作者： lin Tang Rui Zhang Yusi Wang Mohan liu die Hu Yuanda Wang li Yang Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

In the treatment of central nervous system(CNS)diseases such as glioma,Alzheimer's disease(AD)and Parkinson's disease(PD),drugs are expected to reach specific areas of the brain to achieve the desired *** a growing number of therapeutic targets have been identified in preclinical studies,the ones that can ultimately be used in the clinic are ***,the research process and clinical application of drugs for treating CNS diseases are still large *** barriers such as the blood‒brain barrier(BBB)act as selective permeable membranes,allowing only certain molecules to enter the brain;this barrier is the major obstacle restricting the arrival of most drugs to brain ***,nanoparticles,including lipid-based,cell-derived biomimetic,polymeric and inorganic nanoparticles,have gained increasing attention because of their ability to cross physiological barriers,and could play an important role as delivery carriers and ***,clinical applications of nanoparticles in CNS diseases are *** review focuses on the progress of current research on the use of nanoparticles for the treatment of CNS diseases to provide additional insight into the treatment of CNS diseases.

关键词： nanoparticles central nervous system(CNS)diseases clinical applications delivery carriers immunomodulators

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Distributed Least Squares Algorithm of Continuous-Time Stochastic Regression Model Based on Sampled Data

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Journal of Systems Science & Complexity 2024年第2期37卷 609-628页

作者： ZHU Xinghua GAN die liU Zhixin The Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciencesand School of Mathematical SciencesUniversity of Chinese Academy of SciencesBeijing 100190China Zhongguancun Laboratory Beijing 100094China

In this paper,the authors consider the distributed adaptive identification problem over sensor networks using sampled data,where the dynamics of each sensor is described by a stochastic differential *** minimizing a local objective function at sampling time instants,the authors propose an online distributed least squares algorithm based on sampled data.A cooperative non-persistent excitation condition is introduced,under which the convergence results of the proposed algorithm are established by properly choosing the sampling time *** upper bound on the accumulative regret of the adaptive predictor can also be ***,the authors demonstrate the cooperative effect of multiple sensors in the estimation of unknown parameters by computer simulations.

关键词： Cooperative excitation condition distributed least squares regret sampled data stochastic differential equation

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Response of soil nutrients to terracing and environmental factors in the Loess Plateau of China

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Geography and Sustainability 2024年第2期5卷 230-240页

作者： die Chen Wei Wei liding Chen Bojun Ma Hao li Department of Soil and Water Conservation Changjiang River Scientific Research InstituteWuhan 430010China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan 430010China

Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water *** nutrients play a crucial role in determining soil quality,particularly in landscapes prone to *** are influenced by factors such as land-use type,slope aspect,and *** this study,we sought to examine the impact of terracing on soil nutrients(soil organic content(SoC),total nitrogen(TN),nitrate-nitrogen(No_(3)^(-)-N),ammonium nitrogen(NH_(4)^(+)-N),total phosphorus(TP),available phosphorus(AP),total potassium(TK),and available potassium(AK))and how they vary with environmental factors in the Chinese Loess *** the growing season,we collected 540 soil samples from the 0 to 100 cm soil layer across five major land-use types,different slope aspects,and varying ***,a meta-analysis of literature data further corroborated the effective accumulation of soil nutrients through terracing in the Loess *** findings are as follows:(1)Terraced fields,regardless of land-use type,showed a significant improvement in SoC and TN content.(2)Soil nutrient contents within terraced fields were predominantly higher on sunny slopes.(3)Terraces at lower altitudes are characterized by elevated SoC concentrations.(4)A meta-analysis of literature data pertaining to terracing and soil nutrients in this region confirmed the effective accumulation of soil nutri-ents through *** elucidated outcomes of this study offer a profound theoretical underpinning for the accurate planning and management of terraces,the scientific utilization of land resources,and the enhancement of land productivity.

关键词： Terrace Soil nutrients Land-use Slope aspect Altitude Loess Plateau

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Application and progress of artificial intelligence technology in the segmentation of hyperreflective foci in oCT images for ophthalmic disease research

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International Journal of ophthalmology(English edition) 2024年第6期17卷 1138-1143页

作者： Jia-Ning Ying Hu li Yan-Yan Zhang Wen-die li Quan-Yong Yi Ningbo Eye Hospital Wenzhou Medical UniversityNingbo 315042Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina

With the advancement of retinal imaging,hyperreflective foci(HRF)on optical coherence tomography(oCT)images have gained significant attention as potential biological biomarkers for retinal ***,these biomarkers,represented by HRF,present pose challenges in terms of localization,quantification,and require substantial time and *** recent years,the progress and utilization of artificial intelligence(AI)have provided powerful tools for the analysis of biological *** technology enables use machine learning(ML),deep learning(DL)and other technologies to precise characterization of changes in biological biomarkers during disease progression and facilitates quantitative *** on ophthalmic images,AI has significant implications for early screening,diagnostic grading,treatment efficacy evaluation,treatment recommendations,and prognosis development in common ophthalmic ***,it will help reduce the reliance of the healthcare system on human labor,which has the potential to simplify and expedite clinical trials,enhance the reliability and professionalism of disease management,and improve the prediction of adverse *** article offers a comprehensive review of the application of AI in combination with HRF on oCT images in ophthalmic diseases including age-related macular degeneration(AMD),diabetic macular edema(DME),retinal vein occlusion(RVo)and other retinal diseases and presents prospects for their utilization.

关键词： artificial intelligence deep learning hyperreflective foci image analysis

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Different timing for abdominal paracentesis catheter placement and drainage in severe acute pancreatitis complicated by intraabdominal fluid accumulation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 134-142页

作者： Rui Chen Hua-Qiang Chen Rui-die li Hui-Min Lu Department of General Surgery Chengdu Sixth People’s HospitalChengdu 610058Sichuan ProvinceChina West China Center of Exellence for Pancreatitis Institute of Integrated Traditional Chinese and Western MedicineWest ChinaDivision of Pancreatic SurgeryDepartment of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina HospitalSichuan University

BACKGRoUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abdominal paracentesis catheter place-ment and *** To explore the influence of different timing for abdominal paracentesis catheter placement and drainage in SAP complicated by intra-abdominal fluid *** Using a retrospective approach,184 cases of SAP complicated by intra-abdominal fluid accumulation were enrolled and categorized into three groups based on the timing of catheter placement:group A(catheter placement within 2 d of symptom onset,n=89),group B(catheter placement between days 3 and 5 after symptom onset,n=55),and group C(catheter placement between days 6 and 7 after symptom onset,n=40).The differences in progression rate,mortality rate,and the number of cases with organ dysfunction were compared among the three *** The progression rate of group A was significantly lower than those in groups B and groups C(2.25%vs 21.82%and 32.50%,Poportion of patients with at least one organ dysfunction in group A was significantly lower than those in groups B and groups C(41.57%vs 70.91%and 75.00%,Portality rates in group A,group B,and group C were similar(P>0.05).At postoperative day 3,the levels of C-reactive protein(55.41±19.32 mg/L vs 82.25±20.41 mg/L and 88.65±19.14 mg/L,Pocalcitonin(1.36±0.51 ng/mL vs 3.20±0.97 ng/mL and 3.41±0.98 ng/mL,Por necrosis factor-alpha(15.12±6.63 pg/L vs 22.26±9.96 pg/L and 23.39±9.12 pg/L,Poid A(270.06±78.49 mg/L vs 344.41±81.96 mg/L and 350.60±80.42 mg/L,Power in group A compared to those in groups B and group *** length of hospit

关键词： Abdominal paracentesis catheter drainage Timing Severe acute pancreatitis Intra-abdominal fluid Application value

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Compressed Least Squares Algorithm of Continuous-Time linear Stochastic Regression Model Using Sampling Data

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Journal of Systems Science & Complexity 2024年第4期37卷 1488-1506页

作者： XIE Siyu ZHANG Shujun WANG Ziming GAN die School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China China Academy of Aerospace Science and Innovation Beijing 100176China Zhongguancun Laboratory Beijing 100094China

In this paper,the authors consider a sparse parameter estimation problem in continuoustime linear stochastic regression models using sampling *** on the compressed sensing(CS)method,the authors propose a compressed least squares(LS) algorithm to deal with the challenges of parameter *** each sampling time instant,the proposed compressed LS algorithm first compresses the original high-dimensional regressor using a sensing matrix and obtains a low-dimensional LS estimate for the compressed unknown ***,the original high-dimensional sparse unknown parameter is recovered by a reconstruction *** introducing a compressed excitation assumption and employing stochastic Lyapunov function and martingale estimate methods,the authors establish the performance analysis of the compressed LS algorithm under the condition on the sampling time interval without using independence or stationarity conditions on the system *** last,a simulation example is provided to verify the theoretical results by comparing the standard and the compressed LS algorithms for estimating a high-dimensional sparse unknown parameter.

关键词： Compressed excitation condition compressed sensing continuous-time model least squares linear stochastic regression parameter identification sampling data

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Botulinum toxin type A in treating early-stage patients with small-angle acute acquired comitant esotropia

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International Journal of ophthalmology(English edition) 2024年第6期17卷 1094-1101页

作者： Run-Ting Ma die-Wen-Jie Hu lian-Hong Zhou Wen-Ping li Yuan-Jin li Bei-Xi Yi Department of ophthalmology Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina

AIM:To investigate botulinum toxin A(BTXA)efficacy on small-angle(≤25Δ)acute acquired concomitant esotropia(AACE)in early-stage ***:The electronic medical record data of AACE patients during March 2019 and June 2023 were collected in this retrospective and hospital-based cohort study.A total of 72 small-angle AACE patients received BTXA extraocular muscle *** were grouped by onset-to-treatment time(Group A:≤6mo,Group B:>6mo).Deviation of esotropia,eye alignment and stereopsis were analyzed at the period of pre/post-injection(1wk,1,3,and 6mo).orthophoria rate at 6mo(horizontal deviationocular single vision)were considered as outcome ***:There were no significant baseline differences(P>0.05)between two groups except onset-to-treatment time(2mo vs 11mo,Porthophoria rates were in Group A at last follow-up(94.74%vs 73.53%,P=0.013).Post-BTXA deviations of two groups at 1mo showed no difference(P>0.05);while in 3 and 6mo Group A was significantly smaller than group B(all Po statistically significant differences were observed among all post-BTXA deviations of near and distance in Group *** Group B,deviation at 3mo(near:2Δvs 0,Po(near:6Δvs 0,Pompared to deviation at 1wk after *** A showed better stereopsis recovery in last follow-up compared to Group B(80″vs 200″,P=0.002).Both groups obtained improved stereopsis after treatment(Group A:80″vs 300″,Poup B:200″vs 300″,P=0.037).CoNCLUSIoN:BTXA is effective for AACE with small deviation(≤25Δ)in early *** treatment(>6mo)may reduce BTXA *** BTXA intervention benefits long-term eye alignment and stereopsis recovery.

关键词： acute acquired comitant esotropia botulinum toxin type A stereopsis

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Cucurbit[8]uril-regulated face-to-face dimerization assembly enhanced photosensitization and photocatalysis

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Science China Chemistry 2024年第5期67卷 1605-1612页

作者： Haigen Nie die Hu Zhiyao Zeng Yan Fan Yaxin Zhai Xin-Long Ni Key Laboratory of Chemical Biology and Traditional Chinese Medicine Ministry of Educational of ChinaKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of PhysicsHunan Normal UniversityChangsha 410081China

In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole guests(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to-face dimer. These complexation behaviors have been indicated by proton nuclear magnetic resonance(~1H NMR) spectroscopy and isothermal titration calorimetry(ITC),and have been confirmed by X-ray single crystal structural analysis of Q[8]_(3)/G2_(2). While free guests G1–G3 have no ability to sensitize singlet oxygen, they all become effective singlet oxygen sensitizers when complexed with Q[8]. By irradiation of white light, Q[8]_(3)/G_(2) complexes induced selective oxidation of aryl sulfide to aryl sulfoxide in good yields and selective oxidation of dimethyl sulfide(DMS) to dimethyl sulfoxide(DMSo) in excellent yields without over-oxidation to dimethyl sulfone(DMSo_(2))even for elongated irradiation. High-yield photo-oxidation of DMS to DMSo_(2) was only achieved by irradiation of blue light in the presence of Q[8]_(3)/G1_(2), which was also effective in photobleaching of Rhodamine B in water. The higher photo-oxidation power of Q[8]_(3)/G1_(2) has been ascribed to an additional generation of reactive oxygen species besides singlet oxygen.

关键词： host-guest interaction dimerization macrocycles photosensitization

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