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A non-group parallel frequent pattern mining algorithm based on conditional patterns

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Frontiers of Information Technology & Electronic Engineering 2019年第9期20卷 1234-1245页

作者： Zhe-jun KUANG Hang zhou Dong-dai zhou jin-peng zhou Kun YANG College of Computer Science and Technology Changchun UniversityChangchun 130022China School of Economics Changchun UniversityChangchun 130022China School of Information Science and Technology Northeast Normal UniversityChangchun 130117China Division of Engineering Science University of TorontoOntario M5S2E8Canada School of Computer Science and Electronic Engineering University of EssexColchester CO43SQUK

Frequent itemset mining serves as the main method of association rule *** the limitations in computing space and performance,the association of frequent items in large data mining requires both extensive time and effort,particularly when the datasets become increasingly *** the process of associated data mining in a big data environment,the MapReduce programming model is typically used to perform task partitioning and parallel processing,which could improve the execution effciency of the ***,to ensure that the associated rule is not destroyed during task partitioning and parallel processing,the inner-relationship data must be stored in the computer *** inner-relationship data are redundant,storage of these data will significantly increase the space usage in comparison with the original *** this study,we find that the formation of the frequent pattern(FP)mining algorithm depends mainly on the conditional pattern *** on the parallel frequent pattern(PFP)algorithm theory,the grouping model divides frequent items into several groups according to their *** propose a non-group PFP(NG-PFP)mining algorithm that cancels the grouping model and reduces the data redundancy between ***,we present the NG-PFP algorithm for task partition and parallel processing,and its performance in the Hadoop cluster environment is analyzed and *** results indicate that the non-group model shows obvious improvement in terms of computational effciency and the space utilization rate.

关键词： Frequent pattern mining Parallel algorithm Conditional pattern bases MapReduce Big data

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深海沉积物中稀土元素的富集成矿作用

矿物岩石地球化学通报 2024年第1期43卷 79-89页

作者：付宇孙晓明李登峰李政坤彭锦洲黄菲梁泳嘉汤雅月王睿中山大学海洋科学学院广东省海洋资源与近岸工程重点实验室中山大学地球科学与工程学院广东珠海519082

我国虽是稀土大国,但重稀土仍是十分紧缺的关键金属资源。2011年日本学者Kato等在太平洋深海盆地中发现了大规模富含稀土元素的沉积物,引起世界各国高度重视。深海富稀土沉积物广泛分布于海底,其富集稀土元素尤其是相对富集重稀土元素... 详细信息

我国虽是稀土大国,但重稀土仍是十分紧缺的关键金属资源。2011年日本学者Kato等在太平洋深海盆地中发现了大规模富含稀土元素的沉积物,引起世界各国高度重视。深海富稀土沉积物广泛分布于海底,其富集稀土元素尤其是相对富集重稀土元素等关键金属,是继大洋结核结壳、洋中脊热液硫化物、天然气水合物之后一种重要的海洋矿产资源。目前太平洋和印度洋中都证实有大面积富稀土沉积物的存在,我国科学家将深海稀土资源分为4个主要成矿远景区,其中太平洋3个,印度洋1个。富稀土沉积物的矿物组分主要包括生物成因磷灰石(鱼牙和鱼骨)、微结核(铁锰氧化物或氢氧化物)、沸石、黏土矿物等,其中生物磷灰石是最重要的稀土载体。稀土元素直接来源于上覆海水和孔隙水,热液和火山活动可能也有贡献。水深、沉积速率和氧化还原环境等是控制深海稀土元素富集的重要因素,强底流、海底火山和热液活动以及气候事件所导致的陆源输入的变化也会对深海稀土富集产生重要影响。深海稀土成矿作用仍然存在一些尚未解决的科学问题,需进一步加强深海富稀土沉积物成因及超常富集机制等的研究,以丰富和完善深海稀土的成矿模型,为我国在深海稀土富集区的勘探研究与实践提供重要借鉴。

关键词：深海沉积物稀土元素生物磷灰石微结核富集规律成矿作用

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

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Engineering 2024年第7期38卷 144-154页

作者： Jun-Su zhou Long Cheng Yuan Gao Zhan-peng Ge Bin zhou jing-Ya Li jin-Xin Zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids E-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMS-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis Euphorbiaceae Trigofragiloid Structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity

Decreased Nrf2 protein level and low sperm quality in intractable spermatocystitis

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维普期刊数据库

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Asian Journal of Andrology 2024年第2期26卷 189-194页

作者： Shi-Ze Wang Jian-Nan Liu Fen-Fang zhou Ye-jin-peng Wang peng Zhang Song-Tao Cheng Department of Urology Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Health Management and Clinical Medicine School of Medicine and HealthWuhan PolytechnicUniversityWuhan 430071China

To investigate the molecular etiology of low sperm quality in patients with intractable spermatocystitis,spermatozoa samples from patients with persistent hematospermia undergoing transurethral seminal vesiculoscopy and healthy volunteers were *** samples were collected from the seminal vesicles through transurethral seminal vesiculoscopy or by masturbation *** quality was analyzed by a WLJY-9000 color semen analysis *** of tumor necrosis factor alpha(TNFa)and interleukin-6(IL-6)in the seminal plasma was performed using enzyme-linked immunosorbent assay(ELISA).Measurement of H_(2)O_(2)in the seminal plasma was performed with a hydrogen peroxide *** protein levels of nuclear factor erythroid 2-related factor 2(Nrf2)and phosphorylated-Nrf2(p-Nrf2)were measured by western blot analysis and immunofluorescence *** sperm quality parameters and increased levels of inflammatory cytokines(TNFa,IL-6,and H_(2)O_(2))in the seminal plasma were detected among the semen samples from the patients with persistent ***2 and p-Nrf2 were strongly expressed in the nucleus and periphery of human sperm cells,according to the results of the immunofluorescence *** protein levels of Nrf2 and p-Nrf2 were significantly lower in the spermatozoa samples from patients with persistent hematospermia than in those from healthy volunteers with normal sperm *** results suggested that Nrf2 signaling might play a role in the low sperm quality of patients with intractable spermatocystitis.

关键词： H_(2)O_(2) Nrf2 sperm quality spermatocystitis

Identification of Specific RAPD Markers Linked to Anthracnose Resistant Gene in Native Wild Grapes of China

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维普期刊数据库

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Agricultural Sciences in China 2001年第1期 35-39页

作者： WANG Xi-ping WANG Yue-jin zhou peng ZHENG Xue-qin College of Horticulture Northwestern Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 College of Horticulture Northwestern Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 National Key Biotechnology Laboratory for Tropical Crops SCATC Haikou 571101 National Key Biotechnology Laboratory for Tropical Crops SCATC Haikou 571101

Randomly amplified polymorphic DNA (RAPD) was employed to detect molecular markers linked to anthracnose ( Spheceloma ampelinum de Bary) resistant gene in the native wild grapes ( Vitis L. ) of China. RAPD marker OPJ13-300 was linked to anthracnose resistant gene using 90-3 cross F1 V. quinquangularis Rehd (shang-24) × V. vinifera (Longyan). The marker was verified in 90-3 cross F1, Chinese wild grapes and V. riparia and European grape cuitivars. This work has provided a solid basis for molecular marker-assisted selection (MAS) to disease resistance and cloning of disease resistant genes.

关键词： The wild grapes China Anthracnose resistance RAPD

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

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维普期刊数据库

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Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie Yan Bo jin Rufang peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center *** carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature *** was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the *** investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal *** carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 *** to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics

Dynamically lithium-compensated polymer artificial SEI to assist highly stable lithium-rich manganese-based anode-free lithium metal batteries

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Rare Metals 2024年第6期43卷 2527-2535页

作者： Ming-Ji peng jin-Qiu zhou Ting-Ting Han Yang zhou Jie Liu Na Xu Zhen-Kang Wang Wen-Bin Lin Cheng-Lin Yan Key Laboratory of Core Technology of High Specific Energy Battery and Key Materials for Petroleum and Chemical Industry College of EnergySoochow UniversitySuzhou 215006China Light Industry Instituteof Electrochemical Power Sources Suzhou 215006China School of Chemistry and Chemical Engineering Nantong UniversityNantong 226019China e-mail:jliu93@*** State Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai 200245China Centre Energie Materiaux et TélécommunicationsInstitut National de la Recherche ScientifiqueVarennesQC J3X 1S2Canada Zhangjiagang Industrial Technologies Soochow UniversitySuzhou 215006China

Owing to the unique structure,anode-free lithium metal batteries(AFLMBs)have higher energy density and lower production cost than traditional lithium metal batteries(LMBs)or lithium-ion batteries(LIBs),However,AFLMBs suffer from an inherently finite Li reservoir and exhibit poor cycle stability,low Coulombic efficiency(CE)and severe dendrite *** this work,polydiallyl lithium disulfide(PDS-Li)was successfully synthesized and coated on Cu current collector by electrochemical *** PDS-Li acts as an additional lithium resource to compensate for the irreversible loss of lithium during *** addition,the special structure and lithiophilicity of PDS-Li contribute to lower nucleation overpotential and uniform lithium *** coupled with Li-rich manganese-based(LRM)cathode of Li1.2Mn0.54Ni0.13Co0.13O2,the anode-free full cell exhibits significantly improved cycle stability over 100 cycles and capacity retention of 63.3%and 57%after 80 and 100 cycles,*** believe that PDS-Li can be used to ensure stable cycling performance and high-energy-density in AFLMBs.

关键词： Anode-free Artificial solid electrolyte interphase(SEI) Lithium metal batteries Lithium-rich cathode Finite element simulation

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma peng jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1990-1995页

作者： peng-Fei zhou jin-Gen Lu Jia-Dong Zhang Jia-Wen Wang Department of Anorectal Surgery Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200000China

BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign *** SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 *** patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the *** hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of *** anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical *** patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after *** revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract *** The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such *** type,material and the potential risks of rectal foreign bodies should be considered.

关键词： Foreign body impaction Surgical therapy Rectum-sigmoid colon Colonoscopy Case report