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Minor Prenylated Flavonoids from the Twigs of Macaranga adenantha and Their Cytotoxic Activity

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Natural Products and Bioprospecting 2015年第2期5卷 105-109页

作者： Da-Song Yang shuang-mei wang Wei-Bing Peng Yong-Ping Yang Ke-Chun Liu Xiao-Li Li Wei-Lie Xiao Key Laboratory of Economic Plants and Biotechnology Germplasm Bank of Wild Species in Southwest ChinaInstitute of Tibetan Plateau Research at KunmingKunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Biology Institute of Shandong Academy of Sciences Jinan 250014People’s Republic of China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China

Three new minor prenylated flavonoids,named macadenanthins A–C(1–3),together with three known ones(4–6),were isolated from the twigs of Macaranga *** structures were elucidated on the basis of extensive spectroscopic analysis including NMR,UV and *** prenyl moieties in compounds 1–3 were further modified by cyclization and *** new compounds were tested for their cytotoxicity against four cancer cell lines(MCF-7,Hep G2,Hela and P388)and showed IC50 values in the range of 13.76–22.27 lM.

关键词： Macaranga adenantha Prenylated Flavonoids Macadenanthins A-C Cytotoxicity

MixerKT:A Knowledge Tracing Model Based on Pure MLP Architecture

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Computers, Materials & Continua 2025年第1期82卷 485-498页

作者： Jun wang Mingjie wang Zijie Li Ken Chen Jiatian mei Shu Zhang Key Laboratory of Education Informatization for Nationalities Ministry of EducationYunnan Normal UniversityKunming650000China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming650000China

In the field of intelligent education,the integration of artificial intelligence,especially deep learning technologies,has garnered significant *** tracing(KT)plays a pivotal role in this field by predicting students’future performance through the analysis of historical interaction data,thereby assisting educators in evaluating knowledgemastery and tailoring instructional *** knowledge tracingmethods,largely based on Recurrent Neural Networks(RNNs)and Transformer models,primarily focus on capturing long-term interaction patterns in sequential ***,these models may neglect crucial short-term dynamics and other relevant *** paper introduces a novel approach to knowledge tracing by leveraging a pure Multilayer Perceptron(MLP)*** proposeMixerKT,a knowledge tracing model based on theHyperMixer framework,which uniquely integrates global and localMixer feature *** architecture enables more effective extraction of both long-terminteraction trends and recent learning behaviors,addressing limitations in currentmodels thatmay overlook these key *** evaluations on twowidely-used datasets,ASSIS Tments2009 and Algebra2005,demonstrate that MixerKT consistently outperforms several state-of-the-art models,including DKT,SAKT,and Separated Self-Attentive Neural Knowledge Tracing(SAINT).Specifically,MixerKT achieves higher prediction accuracy,highlighting its effectiveness in capturing the nuances of learners’knowledge *** results indicate that our model provides a more comprehensive representation of student learning patterns,enhancing the ability to predict future performance with greater precision.

关键词： Knowledge tracing multilayer perceptron channel mixer sequence mixer

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian wang Yin Zhang Wei-Wei wang mei-Qian Fu Hong-Bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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Science China Technological Sciences 2025年

作者： Kuangda CHEN Huan ZHAO Jiexin ZHANG mei FENG Yiwei wang Jinliang wang Han DING State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin University School of Medical Equipment Science and Engineering Huazhong University of Science and Technology

Narrow space manipulations are crucial for equipment maintenance, as they eliminate the need for disassembly, thus reducing costs and increasing efficiency. Cable-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces, thanks to their interaction compliance and distal dexterity. However, their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation failure. To address this challenge, this paper proposes a novel type of rigid-flexible coupling robot, which increases the stiffness of the robot while ensuring the reachability within a narrow space. To achieve high-accuracy location in a narrow space, kinematic and control methods are proposed. Specifically,the robot forward kinematics are uniformly represented, and the closed-form inverse kinematics solution is derived. Furthermore, in cases where the robot?s structure fails to align with Pieper?s solution, a two-stage search strategy is utilized to solve the inverse kinematics, resulting in a high success rate of 99.1%. Based on the proposed kinematics, a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow spaces. The practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

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Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG mei ZHANG Mingzhe CHEN Hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

雄激素调节小鼠泪膜功能与角膜上皮细胞Mucins表达的体内研究

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国际眼科杂志 2016年第7期16卷 1228-1231页

作者：黎黎郑璇王双梅高鸽康前雁西安交通大学第一附属医院眼科中国陕西省西安市710061 中国陕西省西安市第一医院眼科 710002 中国陕西省西安市第四医院眼科 710004

目的:探讨去势小鼠干眼模型中雄激素浓度对小鼠泪膜稳定性以及角膜上皮细胞Mucins表达的影响。方法:通过双侧睾丸切除去势手术,改变体内雄激素水平,观察泪膜破裂时间的变化,同时在不同时间点采用RT-PCR法与Western-Blot法分别检测小鼠... 详细信息

目的:探讨去势小鼠干眼模型中雄激素浓度对小鼠泪膜稳定性以及角膜上皮细胞Mucins表达的影响。方法:通过双侧睾丸切除去势手术,改变体内雄激素水平,观察泪膜破裂时间的变化,同时在不同时间点采用RT-PCR法与Western-Blot法分别检测小鼠角膜上皮细胞中Muc1和Muc4的mRNA和蛋白水平的表达变化。结果:去势1wk后小鼠睾酮质量浓度下降至0ng/μL;正常对照组、伪手术组及去势术后1、2、4、6、8wk组小鼠BUT分别为68.33±12.86、62.47±3.75、58.67±10.03、47.17±7.64、39.51±3.39、32.67±3.88、31.00±2.36s,其中术后2、4、6、8wk组小鼠泪液BUT值较正常对照与伪手术组均明显缩短,差异均有统计学意义(均P<0.05)。Muc1与Muc4的mRNA与蛋白水平表达,随雄激素浓度下降,表达下调(P<0.05),Muc1在去势后第2wk表达最低,而Muc4在去势后第1wk表达降至最低。结论:在体内,雄激素可调控小鼠角膜上皮Mucins表达,并缩短泪膜破裂时间,参与泪膜稳定性的维持。

关键词：雄激素泪膜破裂时间黏蛋白角膜上皮细胞

Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

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Neural Regeneration Research 2025年第1期20卷 93-106页

作者： Yujie Yang Xinyi Li Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao mei Tian Jian wang Fengtao Liu Chuantao Zuo Key Laboratory of Arrhythmias Ministry of EducationDepartment of Medical GeneticsShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Neurology National Research Center for Aging and MedicineNational Center for Neurological Disordersand State Key Laboratory of Medical NeurobiologyHuashan HospitalFudan UniversityShanghaiChina Department of Nuclear Medicine&PET Center National Center for Neurological Disordersand National Clinical Research Center for Aging and MedicineHuashan HospitalFudan UniversityShanghaiChina International Human Phenome Institutes(Shanghai) ShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of *** review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest *** conducted a thorough literature search using reputable databases such as PubMed and Web of *** criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical *** findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting ***,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo *** validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic *** summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

关键词： aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease parkinsonism positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-mei wang mei-Xia Tao Kai-Ming Mo Xu Chen Shu-Hua Zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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视网膜内界膜平铺覆盖与内界膜剥除治疗巨大型黄斑裂孔疗效的比较

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国际眼科杂志 2018年第12期18卷 2199-2203页

作者：邓瑾孙文涛雷春灵柴芳王双梅王丽萍中国陕西省西安市第四医院眼科 710006

目的:探讨玻璃体切除(par plana vitrectomy,PPV)+视网膜内界膜(inner limiting membrane,ILM)平铺覆盖+玻璃体腔消毒空气填充术与PPV+ILM剥除+玻璃体腔消毒空气填充术治疗巨大型特发性黄斑裂孔(idiopathic macularhole,IMH)和高度近视黄斑裂孔(macular hole,MH)的疗效差异。方法:选取巨大型IMH 40眼,巨大型高度近视性MH 40眼的临床资料进行临床对照研究。20眼巨大型IMH患者行传统ILM剥除(A1组),余20眼行ILM平铺覆盖(A2组); 20眼巨大型高度近视性MH行传统ILM剥除(B1组),余20眼行ILM平铺覆盖(B2组)。术后随诊6mo以上,对比分析MH的闭合率、手术前后最佳矫正视力(best corrected visual acuity,BCVA)改善情况。结果:A组患者手术前后BCVA改善情况差异有统计学意义(F时间=96. 193,P时间 0. 05),术后1、3、6mo差异均有统计学意义(P 0. 05),术后1、3、6mo差异均有统计学意义(P<0. 05)。随访6mo,A1组裂孔闭合16眼(80%),4眼(20%)贴附,A2组裂孔闭合20眼(100%); B1组裂孔闭合14眼(70%),6眼(30%)贴附,B2组中裂孔闭合18眼(90%),2眼(10%)贴附。A1组和A2组组间在黄斑裂孔闭合率上差异无统计学意义(P=0. 053),B1组和B2组组间在黄斑裂孔闭合率上差异无统计学意义(P=0. 118),视网膜内界膜剥除组裂孔闭合30眼(75%),10眼(25%)贴附和平铺覆盖组黄斑裂孔闭合38眼(95%),2眼(5%)贴附,差异有统计学意义(χ2=4. 057,P<0. 05)。结论:对于巨大型IMH和巨大型高度近视MH患者,ILM平铺覆盖治疗组在闭合率及BCVA提高上明显优于ILM剥除组。

关键词：巨大型黄斑裂孔内界膜平铺覆盖组织修复视功能改善