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Precise and Controllable Assembly of Block Copolymers

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Chinese Journal of Chemistry 2023年第1期41卷 93-110页

作者： Bixin Jin Yiqi Chen Yunjun Luo Xiaoyu Li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijing 100081China

With the development of nanotechnology,the precise synthesis of nanoparticles with nicely-defined dimensions and structures has been well-developed,and the functionalization and subsequent applications of the resultant nanostructures are becoming increas-ingly important.Comparing to inorganic nanoparticles,the nanostructures based on soft matters,especially block copolymer as-semblies,are much lower in cost,easier to fabricate and richer in morphology.However,the dimensional control over the block co-polymer assemblies is not as easy.Only in recent decade,with the discovery of living Crystallization-Driven Self-Assembly(CDSA)by Manners and Winnik,researchers become able to precisely tune the sizes of block copolymer assemblies in a relatively wide range.This discovery has inspired tremendous research effort in the self-assembly field,and considerable progress has been made recently.This review summarizes the main progress in the precise and controllable self-assembly field in the past five years,and is mostly fo-cused on four aspects,including in-depth understanding of the assembly methods,extension of this method to two-dimensional nanostructures,utilization of this method to fabricate hierarchical structures,and the potential applications of these well-defined nanostructures.We hope not only to make a periodic systematic summary of previous studies,but also to provide some useful thinking for the future development of this field.

关键词： Nanostructures Micelles Nanotechnology Self-assembly Precise assembly

DQN-based decentralized multi-agent JSAP resource allocation for UAV swarm communication

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系统工程与电子技术：英文版 2023年第2期34卷 289-298页

作者： li Jie DANG xiaoyu li Sai College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

It is essential to maximize capacity while satisfying the transmission time delay of unmanned aerial vehicle(UAV)swarm communication system.In order to address this challenge,a dynamic decentralized optimization mechanism is presented for the realization of joint spectrum and power(JSAP)resource allocation based on deep Q-learning networks(DQNs).Each UAV to UAV(U2U)link is regarded as an agent that is capable of identifying the optimal spectrum and power to communicate with one another.The convolutional neural network,target network,and experience replay are adopted while training.The findings of the simulation indicate that the proposed method has the potential to improve both communication capacity and probability of successful data transmission when compared with random centralized assignment and multichannel access methods.

关键词： joint spectrum and power(JSAP) unmanned aerial vehicle(UAV)swarm communication deep Q-learning network(DQN) UAV to UAV(U2U)

康德哲学视点下人工智能生成物的著作权问题探讨

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法学杂志 2018年第9期39卷 43-54页

作者：李扬李晓宇中山大学法学院广东广州510275

康德"主客体统一认识论"和"人是目的"哲学视点下,无论人工智能发展到何种阶段,都只能作为人利用的客体和工具处理,而不能将其拟制为与人享有平等地位的法律主体。以此为前提,人工智能生成物应当作为人利用人工智能创作的作品并按照现行... 详细信息

康德"主客体统一认识论"和"人是目的"哲学视点下,无论人工智能发展到何种阶段,都只能作为人利用的客体和工具处理,而不能将其拟制为与人享有平等地位的法律主体。以此为前提,人工智能生成物应当作为人利用人工智能创作的作品并按照现行著作权法关于作品的构成要件判断其独创性。在人工智能生成物构成作品的情况下,应按照现行著作权法关于著作权归属的原则处理其权利归属,即人工智能生成物的著作权原则上归属于利用人工智能进行作品创作的作者(自然人或者法人或者非法人单位),例外情况下属于雇主或者委托人。

关键词：康德哲学人工智能生成物主体资格法律属性权利分配

The Origins of Toroidal Micelles from a liquid-crystalline Triblock Copolymer

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Chinese Journal of Chemistry 2020年第12期38卷 1709-1717页

作者： Bixin Jin Guojun liu Xiaoyu Li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Department of Chemistry Queen's University90 Bader LaneKingstonOntarioCanada Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijing 100081China Experimental Centre of Advanced Materials Beijing Institute of TechnologyBeijing 100081China

of main observation and conclusion In this paper,we reported a systematic study on the formation mechanism of bent toroidal micelles from a triblock copolymer poly(acrylic acid)-block-(2-cinnamoyloxylethyl methacrylate)-block-poly(perfluorooctylethyl methacrylate)(PAA-b-PCEMA-b-PFMA)in the binary solvent mixture of methanol and a,a,a-trifluorotoluene(MeOH/TFT)through a heating-cooling procedure.It was found that the formation process of toroids was predominantly kinetic-controlled,and can be influenced by the preparation protocol,solvent composition and stirring rate of the solutions.The toroids were formed via a complicated morphological transition process.At high temperature,the polymer formed bilayered vesicles with bumpy surface,while upon cooling,the vesicles broke and unfolded into bumpy platelet micelles,which subsequently perforated into toroidal and cylindrical micelles upon further cooling.Besides the distinct and unique bumpy vesicle and platelet structures,the transformation mechanisms from vesicular to platelet,and toroidal micelles are also very intriguing,and may provide new insights into the interconversion of micellar morphologies.

关键词： process. crystalline stirring

Efficacy and safety of immune checkpoint inhibitors for advanced non-small cell lung cancer with or without PD-L1 selection:A systematic review and network meta-analysis

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Chinese Medical Journal 2023年第18期136卷 2156-2165页

作者： Yan li Xueyan liang Huijuan li xiaoyu Chen Department of Pharmacy Guangxi Academy of Medical Sciences and the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi 530021China Phase 1 Clinical Trial Laboratory Guangxi Academy of Medical Sciences and the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi 530021China

Background:Immune checkpoint inhibitors(ICIs)are standard treatments for advanced non-small cell lung cancer(NSCLC);however,evidence regarding their relative efficacy and safety is lacking.This study compared the efficacy and safety of all currently available ICI treatments in patients with advanced NSCLC to identify optimal treatment regimens.Methods:PubMed,Cochrane Central Register of Controlled Trials(CENTRAL),MEDliNE,and Embase databases were systematically searched for randomized controlled trials(RCTs)published up to August 8,2022.The primary outcomes were overall survival(OS)and progression-free survival(PFS).Secondary outcomes included objective response rate(ORR)and adverse events(AEs).Results:Forty RCTs involving 22,526 patients were selected,and a total of 26 treatment regimens were identified.Treatment with anti-programmed cell death protein-1(anti-PD-1)provided superior OS compared with anti-programmed death ligand 1(anti-PD-L1)treatment.ICIs plus platinum-based chemotherapy(PBC)were superior to ICIs treatment alone,although the addition of PBC increased treatment toxicity.Cemiplimab ranked first for OS and lowest for any-grade AEs in advanced NSCLC patients without PD-L1 selection.Regarding grade≥3 AEs,the toxicity of ICI monotherapy or ICI-ICI combination was consistently lower than that of the other treatments.For patients without PD-L1 selection,cemiplimab showed the best OS,pembrolizumab plus docetaxel(Pem-DXT)showed the best PFS,and atezolizumab plus bevacizumab and PBC(Atezo-Beva-PBC)showed the best ORR.Pembrolizumab plus PBC and Atezo-Beva-PBC were the most likely optimal treatments for OS and PFS in patients with PD-L1 expressionlimab plus PBC(Sint-PBC)provided the best OS benefit;as for PFS,ICI plus PBC consistently showed greater PFS benefits than ICI or PBC alone.For patients with anti-PD-L1 expression of 1-49%,cam

关键词： Non-small cell lung cancer Immune checkpoint inhibitor Programmed death ligand 1 Cemiplimab Bayesian network meta-analysis

Microstructure and Mechanical Properties of B-Bearing Austenitic Stainless Steel Fabricated by Laser Metal Deposition In-Situ Alloying

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 453-465页

作者： Sheng Huang xiaoyu Zhang Dichen li Qingyu li State Key Laboratory for Manufacturing Systems Engineering Xian Jiaotong UniversityXian 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

In the field repair application of laser metal deposition(LMD),the kinds of powder materials that can be used are limited,while the equipment components are made of various materials.Hence many components have to be repaired with heterogeneous materials.However,it is difficult to match the mechanical properties between the repaired layer and the substrate due to the diff erent materials.Based on the high flexibility of raw materials and processes in LMD,an in-situ alloying method is proposed herein for tailoring the mechanical properties of LMDed alloy.Using diff erent mixing ratios of Fe314 and 316 L stainless steel powders as the control parameter,the microstructure and mechanical properties of B-bearing austenitic stainless steel fabricated by LMD in-situ alloying with diff erent proportions of Fe314 and 316 L particles were studied.With the increase in the concentration of 316 L steel,the volume fraction of the eutectic phase in deposited B-bearing austenitic stainless steel reduced,the size of the austenite dendrite increased,the yield strength and ultimate tensile strength decreased monotonically,while the elongation increased monotonically.Moreover,the fracture mode changed from quasi-cleavage fracture to ductile fracture.By adding 316 L powder,the yield strength,tensile strength,and elongation of deposited B-bearing austenitic stainless steel could be adjusted within the range of 712 MPa–257 MPa,1325 MPa–509 MPa,and 8.7%–59.3%,respectively.Therefore,this work provides a new method and idea for solving the performance matching problem of equipment components in the field repair.

关键词： Additive manufacturing Laser metal deposition In-situ alloying B-bearing austenitic stainless steel Mechanical properties

Molecular mechanisms of cellular metabolic homeostasis in stem cells

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International Journal of Oral Science 2023年第4期15卷 527-539页

作者： Xiaoyu Li Ou Jiang Songlin Wang Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction Beijing Laboratory of Oral Health and Beijing Stomatological HospitalCapital Medical UniversityBeijingChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Immunology Research Center for Oral and Systemic Health Beijing Friendship HospitalCapital Medical UniversityBeijingChina Laboratory for Oral and General Health Integration and Translation Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Research Unit of Tooth Development and Regeneration Chinese Academy of Medical SciencesBeijingChina

Many tissues and organ systems have intrinsic regeneration capabilities that are largely driven and maintained by tissue-resident stem cell populations. In recent years, growing evidence has demonstrated that cellular metabolic homeostasis plays a central role in mediating stem cell fate, tissue regeneration, and homeostasis. Thus, a thorough understanding of the mechanisms that regulate metabolic homeostasis in stem cells may contribute to our knowledge on how tissue homeostasis is maintained and provide novel insights for disease management. In this review, we summarize the known relationship between the regulation of metabolic homeostasis and molecular pathways in stem cells. We also discuss potential targets of metabolic homeostasis in disease therapy and describe the current limitations and future directions in the development of these novel therapeutic targets.

关键词： homeostasis maintained mechanisms

Insulin-like growth factor binding proteins 7 prevents dental pulp-derived mesenchymal stem cell senescence via metabolic downregulation of p21

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Science China(life Sciences) 2022年第11期65卷 2218-2232页

作者： Xiaoyu Li liang Feng Chunmei Zhang Jinsong Wang Songlin Wang Lei Hu Molecular Laboratory for Gene Therapy and Tooth Regeneration Beijing Key Laboratory of Tooth Regeneration and Function ReconstructionBeijing Laboratory of Oral HealthCapital Medical University School of StomatologyBeijing 100050China Immunology Research Center for Oral and Systemic Health Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Biochemistry and Molecular Biology Capital Medical University School of Basic MedicineBeijing 100069China Laboratory for Oral and General Health Integration and Translation Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Research Unit of Tooth Development and Regeneration Chinese Academy of Medical SciencesBeijing 100700China Department of Prosthodontics Capital Medical University School of StomatologyBeijing 100050China

Cellular senescence affects the efficacy of mesenchymal stem cells(MSCs)-mediated tissue regeneration.Insulin-like growth factor binding proteins-7(IGFBP7),as a member of the IGF family,is associated with osteogenic differentiation and the senescence of MSCs,but its exact function and mechanism remain unclear.We found IGFBP7 promoted the osteogenic differentiation and prevented the senescence of dental pulp-derived MSCs(DPSCs),as observed in the gain-of-function and lossof-function analyses,the senescence-associated marker p21 showed the most pronounced expression changes.We demonstrated that IGFBP7 activated the biological activity of SIRT1 deacetylase via metabolism,resulting in a deacetylation of H3K36ac and a decrease of the binding affinity of H3K36ac to p21 promoter,thereby reducing the transcription of p21,which ultimately prevents DPSCs senescence and promotes tissue regeneration.The activation of the mitochondrial electron transport chain(ETC)by Coenzyme Q10 could rescue the promotion of DPSC senescence induced by the knockdown of IGFBP7,whereas the inhibition of ETC by rotenone attenuated the prevention of DPSC senescence induced by IGFBP7 overexpression.In conclusion,our present results reveal a novel function of IGFBP7 in preventing DPSC senescence via the metabolism-induced deacetylation of H3K36ac and reduction of p21 transcription,suggesting that IGFBP7 is a potential target for promoting tissue regeneration in an aging environment.

关键词： dental pulp-derived mesenchymal stem cells insulin-like growth factor binding protein 7 senescence metabolism SIRT1 p21

Highly dispersed Pd clusters/nanoparticles encapsulated in MOFs via in situ auto-reduction method for aqueous phenol hydrogenation

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Journal of Materials Science & Technology 2022年第14期109卷 167-175页

作者： Xiubing Huang Xiaoyu Li Wei Xia Bin Hu Martin Muhler Baoxiang Peng Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 10083China Laboratory of Industrial Chemistry Faculty of Chemistry and BiochemistryRuhr University BochumBochum 44780Germany Max Planck Institute for Chemical Energy Conversion Mülheim a.d.Ruhr 45470Germany

In this work,a novel in situ auto-reduction strategy was developed to encapsulate uniformly dispersed Pd clusters/nanoparticles in MIL-125-NH_(2).It is demonstrated that the amino groups in MIL-125-NH_(2)can react with formaldehyde to form novel reducing groups(-NH-CH_(2)OH),which can in situ auto-reduce the encapsulated Pd^(2+)ions to metallic Pd clusters/nanoparticles.As no additional reductants are required,the strategy limits the aggregation and migration of Pd clusters and the formation of large Pd nanoparticles via controlling the amount of Pd^(2+)precursor.When applied as catalysts in the hydrogenation of phenol in the aqueous phase,the obtained Pd(1.5)/MIL-125-NH-CH_(2)OH catalyst with highly dispersed Pd clusters/nanoparticles with the size of around 2 nm exhibited 100%of phenol conversion and 100%of cyclohexanone selectivity at 70℃ after 5 h,as well as remarkable reusability for at least five cycles due to the large MOF surface area,the highly dispersed Pd clusters/nanoparticles and their excellent stability within the MIL-125-NH-CH_(2)OH framework.

关键词： Pd clusters Pd nanoparticles MIL-125-NH_(2) In situ auto-reduction Double solvent method Hydrogenation of phenol