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Learning Dual-Layer User Representation for Enhanced Item Recommendation

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Computers, Materials & Continua 2024年第7期80卷 949-971页

作者： Fuxi Zhu jin xie Mohammed Alshahrani Applied Research Center of Artificial Intelligence Wuhan CollegeWuhan430212China College of Computer Science South-Central MINZU UniversityWuhan430074China Unmanned.Company Riyadh11564Saudi Arabia

User representation learning is crucial for capturing different user preferences,but it is also critical challenging because user intentions are latent and dispersed in complex and different patterns of user-generated data,and thus cannot be measured ***-based data models can learn user representations by mining latent semantics,which is beneficial to enhancing the semantic function of user ***,these technologies only extract common features in historical records and cannot represent changes in user ***,sequential feature can express the user’s interests and intentions that change time by *** the sequential recommendation results based on the user representation of the item lack the interpretability of preference *** address these issues,we propose in this paper a novel model with Dual-Layer User Representation,named DLUR,where the user’s intention is learned based on two different layer ***,the latent semantic layer adds an interactive layer based on Transformer to extract keywords and key sentences in the text and serve as a basis for *** sequence layer uses the Transformer model to encode the user’s preference intention to clarify changes in the user’s ***,this dual-layer user mode is more comprehensive than a single text mode or sequence mode and can effectually improve the performance of *** extensive experiments on five benchmark datasets demonstrate DLUR’s performance over state-of-the-art recommendation *** addition,DLUR’s ability to explain recommendation results is also demonstrated through some specific cases.

关键词： User representation latent semantic sequential feature interpretability

Decarboxylative Amination with Nitroarenes via Synergistic Catalysis

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Chinese Journal of Chemistry 2024年第4期42卷 351-355页

作者： Meiling Ding Sitian Zhou Shunruo Yao Chengjian Zhu Weipeng Li jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan450001 China

In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary *** protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group *** transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.

关键词： Nitroarenes Amines Synergistic catalysis Carboxylic acids Radical alkylation Amination Photocatalysis Steric hindrance

Octopus-like DNA nanostructure coupled with graphene oxide enhanced fluorescence anisotropy for hepatitis B virus DNA detection

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Chinese Chemical Letters 2024年第6期35卷 531-535页

作者： Jia-Li xie Tian-jin xie Yu-Jie Luo Kai Mao Cheng-Zhi Huang Yuan-Fang Li Shu-Jun Zhen Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Key Laboratory of Luminescent and Real-Time Analytical Chemistry(Southwest University) Chongqing Science and Technology BureauCollege of Pharmaceutical SciencesSouthwest UniversityChongqing 400715China

Fluorescence Anisotropy(FA)is an effective biochemical detection method based on molecular *** oxide(GO)has been extensively used as an FA ***,the enhancement of FA by GO alone is limited and the strong scattering of GO will easily make the measurement of FA *** order to address these problems,an octopus-like DNA nanostructure(ODN)was designed and coupled with GO to enhance the FA together in this *** mimicking the multi-clawed structure of the octopus,the ODN can be adsorbed on GO tightly,which not only could improve the sensitivity because of the double FA enhancement abilities of GO and ODN,but also could improve the specificity due to the decrease of the nonspecific interaction in complex ***,ODN could maintain a certain distance between the fluorophore and GO to reduce the fluorescence quenching efficiency of GO,which could improve the *** method has been applied for the detection of hepatitis B virus DNA(HBV-DNA)in a range of 1-50 nmol/L and the limit of detection(LOD)was 330 pmol/*** addition,the proposed method has been successfully utilized to detect HBV-DNA in human serum,indicating that this method has a great practical application prospect.

关键词： Fluorescence anisotropy Graphene oxide(GO) Octopus-like DNA nanostructure HBV-DNA

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Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical Engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng Xin-Yi Xu jin-Xuan xie Wen-Li Chen Lan Liu Xin-Jian Yin Bi-Shuang Chen School of Marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression Lipase Photodecarboxylase

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Relay C（sp）-H bond trifluoromethylthiolation and amidation by visible light photoredox catalysis

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Science China Chemistry 2024年

作者： Junheng Liu Suqi Yang Shunruo Yao Chengjian Zhu Yong Liu Weipeng Li jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Nanjing Bready Advanced Materials Technology Co. Ltd. State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective functionalization of C（sp3）–H bonds is a straightforward and practical method to construct complex molecule skeletons. In this field, direct transformation of unactivated C（sp3）–H bonds into C（sp3）–SCF3architectures is still a great *** report a highly selective trifluoromethylthiolation of unactivated aliphatic C（sp3）–H bonds by combination of proton-coupled electron transfer（PCET） and hydrogen atom transfer（HAT） strategy. A wide range of structurally diverse alkyl trifluoromethyl sulfides are obtained. Furthermore, the use of two different photocatalysts can realize an unprecedented trifluoromethylthiolation and amidation cascade of different C（sp3）–H bonds. It can afford a good access to bifunctionalized molecules in synthetically useful yields.

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Relay C（sp3）-H bond trifluoromethylthiolation and amidation by visible light photoredox catalysis

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Science China Chemistry 2024年第11期 3844-3850页

作者： Junheng Liu Suqi Yang Shunruo Yao Chengjian Zhu Yong Liu Weipeng Li jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Nanjing Bready Advanced Materials Technology Co. Ltd. State Key Laboratory of Natural Medicines China Pharmaceutical University

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热压印成型复合微透镜阵列的微光学照明特性

光学精密工程 2024年第9期32卷 1371-1383页

作者：胡满凤李磊谢晋广州铁路职业技术学院电气工程学院广东广州511300 华南理工大学机械与汽车工程学院广东广州510641

在LED照明中,光线分布不均产生的眩光及光线中的紫外光、蓝光成分容易造成视觉疲劳和眼睛损伤,目前主要是以调节光源为主,纳米级光波段调节的表面结构加工成本较高。因此,利用热压印快速成型技术开发了一种微米尺度的复合微透镜阵列导光... 详细信息

在LED照明中,光线分布不均产生的眩光及光线中的紫外光、蓝光成分容易造成视觉疲劳和眼睛损伤,目前主要是以调节光源为主,纳米级光波段调节的表面结构加工成本较高。因此,利用热压印快速成型技术开发了一种微米尺度的复合微透镜阵列导光板,探究健康照明的复合微透镜尺度效应。首先分析微棱镜表面小微透镜的深宽比与反射电场分布的关系,然后研究导光板的微结构参数对漫反射率、镜面反射率和透射率的影响。最后,对比市面上丝网印刷微点、微棱镜阵列等结构导光板,研究复合微透镜微米尺度对照度、均匀度等微光学性能的影响。分析表明:当小微透镜深宽比在0.6~1内时,紫外光和蓝光的反射面有更小的反射电场变异系数,说明其漫反射大。实验结果表明:热压印技术可以在4 s内将微透镜高5~30μm和微棱镜高10~80μm的复合微透镜阵列导光板加工成型;照度均匀度随着小微透镜深宽比的增大而增大,照度分别比微棱镜和丝网印刷微点阵列提高45%和83%;与微棱镜相比,紫外光和蓝光的漫反射率分别提高8%和18%,镜面反射率下降80%~83%。控制复合微透镜的深宽比可以减少照明眩光,抑制紫外光和蓝光。

关键词：复合微透镜阵列热压印微成型微光学性能健康照明

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带仿生躯干的被动行走机器人步态特性

西南交通大学学报 2024年第2期59卷 477-484页

作者：魏巍丁维高谢进西南交通大学机械工程学院四川成都610031

为改善被动行走机器人的步态特性,受人体躯干同时具有刚性骨骼和柔性软组织启发,提出一种带刚柔仿生躯干的被动行走机器人模型,并研究其非线性动力学特性.将仿生躯干柔性部分等效为带质量的弹簧阻尼器,建立仿生躯干被动行走机器人的动... 详细信息

为改善被动行走机器人的步态特性,受人体躯干同时具有刚性骨骼和柔性软组织启发,提出一种带刚柔仿生躯干的被动行走机器人模型,并研究其非线性动力学特性.将仿生躯干柔性部分等效为带质量的弹簧阻尼器,建立仿生躯干被动行走机器人的动力学模型.分别分析仿生躯干的等效弹性系数、等效阻尼系数、等效质量对被动行走机器人的行走步长和步行速度的影响规律,并与刚性躯干模型的结果进行对比.研究结果表明:相比于刚体躯干,仿生躯干使得被动行走具有更加丰富的步态行为;仿生躯干柔性不仅影响被动行走的行走步长及行走速度,还影响被动行走的稳定性;适当的躯干柔性可以在维持稳定周期步态的同时,提高被动行走机器人的行走步长及步行速度;与刚性躯干相比,带仿生躯干的被动行走步长能提高12%,行走速度能提高2%.

关键词：步行机器人被动行走躯干柔性步态特性

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2024年

作者： Qingyun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center (ChemBIC)School of Chemistry and Chemical EngineeringNanjing University Green Catalysis Center College of ChemistryZhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging *** selective alkylation of peptides can alter the biological activity and physical properties of molecules,and it has gained significant research *** herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis.A wide range of structurally diverse primary,secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of *** protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups.A series of relay transformations to construct cyclic peptides,to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic *** addition,mechanistic studies and density functional theory (DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer (SET) mechanism.

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