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An Approximation Algorithm Based on Seeding Algorithm for Fuzzy k-Means Problem with Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 387-409页

作者： wen-Zhao Liu min Li School of Mathematics and Statistics Shandong Normal UniversityJinan 250014ShandongChina

As a classic NP-hard problem in machine learning and computational geometry,the k-means problem aims to partition the given dataset into k clusters according to the minimal squared Euclidean *** from k-means problem and most of its variants,fuzzy k-means problem belongs to the soft clustering problem,where each given data point has relationship to every center *** to fuzzy k-means problem,fuzzy k-means problem with penalties allows that some data points need not be clustered instead of being paid *** this paper,we propose an O(αk In k)-approximation algorithm based on seeding algorithm for fuzzy k-means problem with penalties,whereαinvolves the ratio of the maximal penalty value to the minimal ***,we implement numerical experiments to show the effectiveness of our algorithm.

关键词： Approximation algorithm Seeding algorithm Fuzzy k-means problem with penalties

Publication trends of Leber congenital amaurosis researches:a bibliometric study during 2002-2022

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1501-1509页

作者： Xiao-Xu huan. Yi-min Wang min-Yue Xie Yi-Qing Sun Xiao-huan.Zhao Yu-Hong Chen Jie-Qiong Chen Si-Yang Han min-wen Zhou Xiao-Dong Sun Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China National Clinical Research Center for Eye Disease Shanghai 200080China Shanghai Key Laboratory of Ocular Fundus Diseases Shanghai 200080China Shanghai Engineering Center for Visual Science and Photomedicine Shanghai 200080China Department of Ophthalmology Zhongshan HospitalFudan UniversityShanghai 200030China Beijing Tongren Hospital Capital Medical UniversityBeijing 100054China Eberly College of Science Penn State UniversityUniversity Park 16802-1503United States

AIM:To analyze the changes in scientific output relating to Leber congenital amaurosis(LCA)and forecast the study trends in this ***:All of the publications in the field of LCA from 2002 to 2022 were collected from Web of Science(WOS)*** analyzed the quantity(number of publications),quality(citation and H-index)and development trends(relative research interest,RRI)of published LCA research over the last two ***,VOSviewer software was applied to define the co-occurrence network of keywords in this ***:A total of 2158 publications were ultimately *** found that the focus on LCA kept rising and peaked in 2015 and 2018,which is consistent with the development trend of gene *** USA has contributed most to this field with 1162 publications,56674 citations and the highest H-index value(116).The keywords analysis was divided into five clusters to show the hotspots in the field of LCA,namely mechanism-related,genotype-related,local phenotype-related,system phenotype-related,and *** also identified gene therapy and antiretinal degeneration therapy as a major focus in recent ***:Our study illustrates historical research process and future development trends in LCA *** may help to guide the orientation for further clinical diagnosis,treatment and scientific research.

关键词： VOSviewer bibliometrics Leber congenital amaurosis gene therapy hotpots

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： wenxuan Zhang Mengran Zhang Hongjuan Wang wen Zhang min Zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1).The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

Macrocyclic peptides:up-and-coming weapons to combat antimicrobial resistance

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1786-1787页

作者： wen-Jing Wang Xiang-min Dong Guo-Bo L Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuanChina Key Laboratory of Drug Targeting and Drug Delivery System of ministry of Education Department of Medicinal ChemistryWest China School of PharmacySichuan UniversityChengduSichuanChina

Recently,two companion papers published in Nature reported a first-in-class tethered macrocyclic peptide antibiotic targeting carbapenem-resistant ***(CRAB)and unveiled their unique antibacterial mechanism,which invol... 详细信息

关键词： outer macrocyclic Macrocyclic

The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn_(6)Ga_(6)S_(16)(Ae=Ca,Sr)

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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang Shao-min Pei wen-Fa Chen Bin-wen Liu Xiao-ming Jiang Guo-Cong Guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng YANG wen-zhi GAO min HU Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

Exploiting blockchain for dependable services in zero-trust vehicular networks

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Frontiers of Computer Science 2024年第2期18卷 157-166页

作者： min HAO Beihai TAN Siming WANG Rong YU Ryan wen LIU Lisu YU School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Integrated Circuits Guangdong University of TechnologyGuangzhou 510006China School of Navigation Wuhan University of TechnologyWuhan 430063China School of Information Engineering Nanchang UniversityNanchang 330031China

The sixth-generation(6G)wireless communication system is envisioned be cable of providing highly dependable services by integrating with native reliable and trustworthy ***-trust vehicular networks is one of the typical scenarios for 6G dependable *** the technical framework of vehicle-and-roadside collaboration,more and more on-board devices and roadside infrastructures will communicate for information *** reliability and security of the vehicle-and-roadside collaboration will directly affect the transportation *** a zero-trust vehicular environment,to prevent malicious vehicles from uploading false or invalid information,we propose a malicious vehicle identity disclosure approach based on the Shamir secret sharing ***,a two-layer consortium blockchain architecture and smart contracts are designed to protect the identity and privacy of benign vehicles as well as the security of their private *** that,in order to improve the efficiency of vehicle identity disclosure,we present an inspection policy based on zero-sum game theory and a roadside unit incentive mechanism jointly using contract theory and subjective logic *** verify the performance of the entire zero-trust solution through extensive simulation *** the premise of protecting the vehicle privacy,our solution is demonstrated to significantly improve the reliability and security of 6G vehicular networks.

关键词： sixth-generation(6G) zero-trust block-chain vehicular networks privacy preservation

Bone block from lateral window-correcting vertical and horizontal bone deficiency in maxilla posterior site:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2109-2115页

作者： Yu-Lan Wang wen-Jun Shao min Wang State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool and Hospital of StomatologyWuhan UniversityWuhan 430079Hubei ProvinceChina Department of Oral Implantology School and Hospital of StomatologyWuhan UniversityWuhan 430079Hubei ProvinceChina

BACKGROUND Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 ***,managing cases becomes more challenging when a maxillary sinus pseudocyst is present or when there is insufficient bone *** this case,we utilized the bone window prepared during the lateral window sinus lift as a shell for horizontal bone *** allowed for simultaneous horizontal and vertical bone augmentation immediately after the removal of the maxillary sinus *** SUMMARY A 28-year-old female presented to our clinic with the chief complaint of missing upper left posterior *** examination showed a horizontal deficiency of the alveolar ridge *** height of the alveolar bone was approximately 3.6 mm on cone beam computed tomography(CBCT).And a typical well-defined'dome-shaped'lesion in maxillary sinus was observed on CBCT *** lateral bony window was prepared using a piezo-ultrasonic device,then the bony window was fixed to the buccal side of the 26 alveolar ridge using a titanium screw with a length of 10 mm and a diameter of 1.5 *** space between the bony window and the alveolar ridge was filled with Bio-Oss,covered with a Bio-Gide collagen membrane,and subsequently *** months later,the patient’s bone width increased from 4.8 to 10.5 mm,and the bone height increased from 3.6 to 15.6 ***,a Straumann^(■)4.1 mm×10 mm implant was *** final all-ceramic crown restoration was completed four months later,and both clinical and radiographic examinations showed that the implant was successful,and the patient was satisfied with the *** The bone block harvested from the lateral window sinus lift can be used for simultaneous horizontal bone augmentation acting as a shell for good two-dimensional bone augmentation.

关键词： Sinus lift Lateral window Dental implant Horizontal bone augmentation Case report

Development and validation of a nomogram for predicting in-hospital mortality of intensive care unit patients with liver cirrhosis

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World Journal of Hepatology 2024年第4期16卷 625-639页

作者： Xiao-Wei Tang wen-Sen Ren Shu huan. Kang Zou huan.Xu Xiao-min Shi Wei Zhang Lei Shi Mu-Han Lü Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Nuclear Medicine and Molecular Imaging Key Laboratory The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Department of Gastroenterology Lianshui People’Hospital of Kangda College Affiliated to Nanjing Medical UniversityHuaian 223499Jiangsu ProvinceChina

BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality *** To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver *** We extracted demographic,etiological,vital sign,laboratory test,comorbidity,complication,treatment,and severity score data of liver cirrhosis patients from the Medical Information Mart for Intensive Care IV(MIMIC-IV)and electronic ICU(eICU)collaborative research database(eICU-CRD).Predictor selection and model building were based on the MIMIC-IV *** variables selected through least absolute shrinkage and selection operator analysis were further screened through multivariate regression analysis to obtain final *** final predictors were included in the multivariate logistic regression model,which was used to construct a ***,we conducted external validation using the *** area under the receiver operating characteristic curve(AUC),decision curve,and calibration curve were used to assess the efficacy of the *** Risk factors,including the mean respiratory rate,mean systolic blood pressure,mean heart rate,white blood cells,international normalized ratio,total bilirubin,age,invasive ventilation,vasopressor use,maximum stage of acute kidney injury,and sequential organ failure assessment score,were included in the multivariate logistic *** model achieved AUCs of 0.864 and 0.808 in the MIMIC-IV and eICU-CRD databases,*** calibration curve also confirmed the predictive ability of the model,while the decision curve confirmed its clinical *** The nomogram has high accuracy in predicting in-hospital *** the included predictors may help improve the prognosis of patients.

关键词： Liver cirrhosis Intensive care unit Nomogram Predicting model Mortality