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Constrained reinforcement learning with statewise projection: a control barrier function approach

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Science China(Information Sciences) 2024年第3期67卷 136-154页

作者： Xinze JIN Kuo li Qingshan jia Department of Automation Tsinghua University

Safety is a critical issue for reinforcement learning(RL), as it may be risky for some actual applications if the learning process involves unsafe exploration. Instead of formulating constraints as expectationbased in constrained RL, considering statewise safety in constrained RL is more meaningful. This work aims to address the issue of safe projection in RL by introducing a control barrier function that inherently learns a safe policy through a set certificate. We seek to analyze some theoretical properties of safe projection in the learning process, including convergence and performance bound, and extend the discussion into ensembles and guided controllers. Moreover, we approach analytical solutions for deterministic and stochastic system dynamics. Experimental results in different tasks show that the proposed method achieves better effects in terms of both performance and safety.

关键词： reinforcement learning safe projection control barrier function

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Anti-osteosarcoma trimodal synergistic therapy using NiFe-LDH and MXene nanocomposite for enhanced biocompatibility and efficacy

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1329-1344页

作者： Yani Xu Lan Yang Min li Haozhou Shu na jia Yunzhen Gao Rongying Shi Xiaojia Yang Zhirong Zhang ling Zhang Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry West China School of PharmacySichuan UniversityChengdu 610041China Med-X Center for Materials College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Osteosarcoma is usually resistant to immunotherapy and,thus primarily relies on surgical resection and high-dosage ***,less invasive or toxic therapies such as photothermal therapy(PTT)and chemodynamic therapy(CDT)generally failed to show satisfactory *** multimodal therapies with proper safety profiles may provide better solutions for ***,a simple nanocomposite that synergistically combines CDT,PTT,and chemotherapy for osteosarcoma treatment was *** this composite,small 2D Ni Fe-LDH flakes were processed into 3D hollow nanospheres via template methods to encapsulate 5-Fluorouracil(5-FU)with high loading *** nanospheres were then adsorbed onto larger 2D Ti3C2MXene monolayers and finally shielded by bovine serum albumin(BSA)to form 5-FU@Ni Fe-LDH/Ti3C2/BSA nanoplatforms(5NiTiB).Both in vitro and in vivo data demonstrated that the 5-FU induced chemotherapy,Ni Fe-LDH driven chemodynamic effects,and MXene-based photothermal killing collectively exhibited a synergistic“all-in-one”anti-tumor effect.5NiTiB improved tumor suppression rate fromnanotherapeutic platform achieved higher therapeutic efficacy with a lower agent dose,thereby minimizing side ***,the composite is simple to produce,enabling the fine-tuning of dosages to suit different ***,the platform is versatile and efficient,with potential for further development.

关键词： Osteosarcoma NiFe-LDH MXene Chemodynamic therapy Photothermal therapy Chemotherapy 5-Fluorouracil nanocomposite

Energy Density Dependence of Bonding Characteristics of Selective Laser-Melted Nb–Si-Based Alloy on Titanium Substrate

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 477-486页

作者： Yue-ling Guo li-na jia Bin Kong Yong-lin Huang Hu Zhang School of Materials Science and Engineering Beihang University

Spherical Nb–20Si–24Ti–2Cr–2Al pre-alloyed powders were processed by selective laser melting（SLM） on Ti6Al4V substrates with different energy densities. A series of single tracks and single layers were produced using different processing parameters, including powder size, laser power, scanning speed and hatch distance. Results showed that the pre-alloyed powders ranging from 45 to 75 lm were more applicable to SLM with less balling tendency, in comparison with those between 75 and 180 lm. The increase in linear energy density（LED） resulted in the decrease in contact angle and the increase in the width of single track as well as its penetration depth into the substrate. Smaller hatch distance leaded to a larger remelted part of the former track and a higher volumetric laser energy density. With a thickness of 75.6 lm, an interfacial intermediate layer, enriched in Ti and depleted in Nb, Si, Cr and Al, was formed between the SLM part and the Ti6Al4V substrate. The mechanisms of the elimination of balling phenomenon by employing a higher LED and the interfacial bonding characteristics between Nb–Si-based alloys via SLM and the Ti6Al4V substrate were discussed.

关键词： Nb-Si alloys Selective laser melting Additive manufacture Bonding character Microstructure

Electrochemical reconstruction of non-noble metal-based heterostructure nanorod arrays electrodes for highly stable anion exchange membrane seawater electrolysis

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Journal of Energy Chemistry 2024年第4期91卷 370-382页

作者： Jingchen na Hongmei Yu Senyuan jia Jun Chi Kaiqiu Lv Tongzhou li Yun Zhao Yutong Zhao Haitao Zhang Zhigang Shao Fuel Cell System and Engineering Laboratory Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Direct seawater electrolysis for hydrogen production has been regarded as a viable route to utilize surplus renewable energy and address the climate ***,the harsh electrochemical environment of seawater,particularly the presence of aggressive Cl^(-),has been proven to be prone to parasitic chloride ion oxidation and corrosion reactions,thus restricting seawater electrolyzer ***,hierarchical structure(Ni,Fe)O(OH)@NiCoS nanorod arrays(nas)catalysts with heterointerfaces and localized oxygen vacancies were synthesized at nickel foam substrates via the combination of hydrothermal and annealing methods to boost seawater *** hiera rchical nanostructure of NiCoS nas enhanced electrode charge transfer rate and active surface area to accelerate oxygen evolution reaction(OER)and generated sulfate gradient layers to repulsive aggressive Cl^(-).The fabricated heterostructure and vacancies of(Ni,Fe)O(OH)tuned catalyst electronic structure into an electrophilic state to enhance the binding affinity of hydroxyl intermediates and facilitate the structural transformation into amorphousγ-NiFeOOH for promoting ***,through operando electrochemistry techniques,we found that theγ-NiFeOOH possessing an unsaturated coordination environment and lattice-oxygen-participated OER mechanism can minimize electrode Cl^(-)corrosion enabled by stabilizing the adsorption of OH*intermediates,making it one of the best OER catalysts in the seawater medium reported to ***,these catalysts can deliver current densities of 100 and 500 mA cm-2for boosting OER at minimal overpotentials of 245and 316 mV,respectively,and thus prevent chloride ion oxidation ***,a highly stable anion exchange membrane(AEM)seawater electrolyzer based on the non-noble metal heterostructure electrodes reached a record low degradation rate under 100μV h-1at constant industrial current densities of 400 and 600 mA cm-2over 300 h,which exhibits a promi

关键词： Direct seawater electrolysis Anion exchange membrane water electrolysis Oxygen evolution reaction Oxygen vacancies Operando electrochemistry techniques

QTL analysis of leaf photosynthesis rate and related physiological traits in Brassica napus

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Journal of Integrative Agriculture 2015年第7期14卷 1261-1268页

作者： YAN Xing-ying QU Cun-min li jia-na CHEN li liU lie-zhao College of Agronomy and Biotechnology Southwest University Biotechnology Research Center Southwest University

Rapeseed （Brassica napus L.） oil is the crucial source of edible oil in China. In addition, it can become a major renewable and sustainable feedstock for biodiesel production in the future. It is known that photosynthesis products are the primary sources for dry matter accumulation in rapeseed. Therefore, increasing the photosynthetic efficiency is desirable for the raise of rapeseed yield. The objective of the present study was to identify the genetic mechanism of photosynthesis based on the description of relationships between different photosynthetic traits and their quantitative trait loci （QTL） by using a recombinant inbred line （RIL） population with 172 lines. Specifically, correlation analysis in this study showed that internal CO2 concentration has negative correlations with other three physiological traits under two different stages. Totally, 11 and 12 QTLs of the four physiological traits measured at the stages 1 and 2 were detected by using a high-density single nu- cleotidepolymorphism （SNP） markers linkage map with composite interval mapping （CIM）, respectively. Three co-localized QTLs on A03 were detected at stage 1 with 5, 5, and 10% of the phenotypic variation, respectively. Other two co-localized QTLs were located on A05 at stage 2, which explained up to 12 and 5% of the phenotypic variation, respectively. The results are beneficial for our understanding of genetic control of photosynthetic physiological characterizations and improvement of rapeseed yield in the future.

关键词： Brassica napus photosynthesis quantitative trait loci (QTL)

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： ZHANG Zhiqiang jia li DANG Chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive *** boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling *** comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in *** thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and *** literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also *** emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were *** future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression

Anti-OX40 Antibody Combined with HBc VLPs Delays Tumor Growth in a Mouse Colon Cancer Model

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Biomedical and Environmental Sciences 2024年第2期37卷 187-195页

作者： liU jia jia SU Qiu Dong YI Yao SHEN li Ping BI Sheng li national Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic *** this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core viruslike particles(HBc VLPs)therapy using a mouse colon cancer *** Humanized B-h OX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-h OX40 *** growth was *** cytometric analysis was performed to evaluate the populations of T cell subsets in the *** The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination *** studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc *** Combination therapy of anti-h OX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy.

关键词： Anti-OX40 antibody Hepatitis B core virus-like particles Tumor Combination therapy

Therapeutic strategies of targeting nonapoptotic regulated cell death (RCD) with smallmolecule compounds in cancer

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Acta Pharmaceutica Sinica B 2024年第7期14卷 2815-2853页

作者： Xin Jin Wenke Jin linlin Tong jia Zhao Lan Zhang na lin Department of Ultrasound Department of Medical Oncology and Department of Hematologythe First Hospital of China Medical UniversityChina Medical UniversityShenyang 110001China Sichuan Engineering Research Center for Biomimetic Synthesis of natural Drugs School of Life Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Regulated cell death(RCD)is a controlled form of cell death orchestrated by one or more cascading signaling pathways,making it amenable to pharmacological *** subroutines can be categorized as apoptotic or non-apoptotic and play essential roles in maintaining homeostasis,facilitating development,and modulating *** evidence has recently revealed that RCD evasion is frequently the primary cause of tumor *** non-apoptotic RCD subroutines have garnered attention as promising cancer therapies due to their ability to induce tumor regression and prevent relapse,comparable to ***,they offer potential solutions for overcoming the acquired resistance of tumors toward apoptotic *** an increasing understanding of the underlying mechanisms governing these non-apoptotic RCD subroutines,a growing number of small-molecule compounds targeting single or multiple pathways have been discovered,providing novel strategies for current cancer *** this review,we comprehensively summarized the current regulatory mechanisms of the emerging non-apoptotic RCD subroutines,mainly including autophagy-dependent cell death,ferroptosis,cuproptosis,disulfidptosis,necroptosis,pyroptosis,alkaliptosis,oxeiptosis,parthanatos,mitochondrial permeability transition(MPT)-driven necrosis,entotic cell death,NETotic cell death,lysosome-dependent cell death,and immunogenic cell death(ICD).Furthermore,we focused on discussing the pharmacological regulatory mechanisms of related small-molecule *** brief,these insightful findings may provide valuable guidance for investigating individual or collaborative targeting approaches towards different RCD subroutines,ultimately driving the discovery of novel small-molecule compounds that target RCD and significantly enhance future cancer therapeutics.

关键词： Regulated cell death(RCD) Non-apoptotic RCD subroutine Autophagy Ferroptosis Necroptosis Regulatory mechanism Small-molecule compound Cancer therapy

Accurate Analysis of Multi-Mode Interferometric Optical Fiber Sensor

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Photonic Sensors 2024年第1期14卷 48-58页

作者： lijun li Congying jia Qian MA Tianzong XU College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590.China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology Qingdao 266590China

In view of the problem that the sensing characteristics of the multi-mode interferometric fiber sensors cannot be accurately analyzed,an analysis method based on the fast Fourier transform(FFT)and inverse fast Fourier transform(IFFT)is proposed and demonstrated theoretically and *** suitabilities of the rectangular window function with the narrow main lobe(high spectrum resolution)and low side lobe(high main mode energy leakage)and the Hanning window function with the wide main lobe(low spectrum resolution)and high side lobe(high energy concentration)in this kind of sensor analysis are discussed,*** method can not only realize the sensing performance analysis of the various modes,but also overcome the inconsistency of the different interference wavelength(dip)sensing characteristics in the conventional analysis *** the same time,this method is also beneficial to solve the repetitive problem of such sensors.

关键词： Window function FFT optical fiber interferometric sensor analysis method