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Rearranged Dichapetalin-Type Triterpenoids with Cytotoxic Activity from Dichapetalum gelonioides

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Chinese Journal of Chemistry 2022年第21期40卷 2531-2538页

作者： Xin-Hua Gao Xi-Yuan Wang jun-su zhou Yan Zhang Hong-Chun Liu Bin zhou Jian-Min Yue State Key Laboratory of Drug Research Shanghai lnstitute of Materia MedicaChinese Academy of SciencesShanghai 201203China Research Units of Discovery of New Drug Lead Molecules Chinese Academy of Medical SciencesShanghai 201203china Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantaiShandong 264117China

Dichagelinoids A—C(1—3),three unusual dichapetalin-type triterpenoids,together with two biogenetically related derivatives dichagelinoids D and E(4 and 5)were isolated and characterized by solid data from Dichapetalum *** 1—3 possess a common rearranged C ring and different C6—C2 modified motifs at the A *** evaluation revealed that compounds 1—3 showed distinct cytotoxic activity against the tested human cancer cell lines.

关键词： Dichapetalum gelonioides Natural products Dichapetalin-type triterpenoids Structural elucidation Cytotoxic activity

cis-Clerodane Diterpenoids with Structural Diversity and Anti-inflammatory Activity from Tinospora crispa

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Chinese Journal of Chemistry 2022年第24期40卷 2882-2892,I0002页

作者： Jin-Qiu You Yi-Nan Liu jun-su zhou Xin-Yu sun Chun Lei Qing Mu Jing-Ya Li Ai-jun Hou School of Pharmacy Fudan UniversityShanghai201203 China School of Pharmacy Shanghai Jiao Tong UniversityShanghai200240 China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai201203 China

Twelve new cis-clerodane diterpenoids, designated as crispinoids A—L (1—12), together with three known analogues (13—15), were isolated from Tinospora crispa. Their structures were fully assigned by comprehensive spectroscopic techniques, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) analyses. The isolated clerodanes displayed diverse heterocyclic frameworks including 6/6/6-, 6/5/6/6-, 6/6/5-, 6/6-, and 6/5/6-fused ring systems. Some of the isolates showed ATP-citrate lyase (ACLY) and nuclear factor kappa B (NF-κB) pathway inhibition. The NF-κB inhibitors further suppressed the lipopolysaccharide (LPS)-induced inflammatory responses in RAW 264.7 cells.

关键词： Natural products Structure elucidation Tinospora crispa ATP-citrate lyase Nuclear factor kappa B

Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： You QIAOBEN Chengyang YING Xinning zhou Hang su jun ZHU Bo ZHANG Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 135-145页

作者： su Shuo Long jun Duan Qinghua zhou Han Zhao Yi SINOPEC Research Institute of Petroleum Processing Co.Ltd. Beijing 100083

To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established *** molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular *** results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen *** on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur *** results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions.

关键词： lubricating oil antioxidant molecular mechanism molecular design antioxidant performance

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Targeted screening of an anti-inflammatory polypeptide from Rhopilema esculentum Kishinouye cnidoblasts and elucidation of its mechanism in alleviating ulcerative colitis based on an analysis of the gut microbiota and metabolites

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Food Science and Human Wellness 2024年第3期13卷 1336-1347页

作者： Ziyan Wang Qiuyue Shi Ying Feng Jiaojiao Han Chenyang Lu jun zhou Zhonghua Wang Xiurong su State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingbo 315000China School of Marine Science Ningbo UniversityNingbo 315000China Key Laboratory of Aquaculture Biotechnology(Ningbo University) Ministry of EducationNingbo UniversityNingbo 315000China College of Life Sciences Tonghua Normal UniversityTonghua 134000China Shandong Beiyou Biotechnology Co. Ltd.Weifang 261000China

Ulcerative colitis(UC)is a recurrent inflammatory bowel disease that imposes a severe burden on families and *** recent years,exploiting the potential of marine bioactive peptides for the treatment of diseases has become a topic of intense research *** study revealed the mechanism underlying the protective effect of the dominant polypeptide PKKVV(Pro-Lys-Lys-Val-Val)of Rhopilema esculentum cnidoblasts against DSS-induced UC through a combined analysis of the metagenome and serum ***,the polypeptide composition of *** cnidoblasts was determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF/TOF-MS).Molecular docking showed that the dominant peptide PKKVV could bind better with tumor necrosis factor-α(TNF-α)than the original *** animal experiments suggested that PKKVV could modulate disorganized gut microorganisms in mice with UC;affect serum metabolites through the arachidonic acid,glycerophospholipid and linoleic acid metabolism pathways;and further alleviate UC *** study provides a reference for the comprehensive development of marine bioactive substances and nonpharmaceutical treatments for UC.

关键词： Ulcerative colitis Rhopilema esculentum Kishinouye Cnidoblasts Marine bioactive polypeptides Metagenome Serum metabolome

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Omnidirectional color wavelength tuning of stretchable chiral liquid crystal elastomers

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Light(Science & Applications) 2024年第6期13卷 1062-1074页

作者： Seungmin Nam Wontae jung jun Hyuk Shin su Seok Choi Department of Electrical Engineering Pohang University of Science and Technology(POSTECH)PohangKorea

Wavelength-tunable structural colors using stimuli-responsive materials,such as chiral liquid crystals(CLCs),have attracted increasing attention owing to their high functionality in various tunable photonic ***,on-demand omnidirectional wavelength control is highly desirable from the perspective of wavelength-tuning ***,despite numerous previous research efforts on tunable CLC structural colors,only mono-directional wavelength tuning toward shorter wavelengths has been employed in most studies to *** this study,we report the ideally desired omnidirectional wavelength control toward longer and shorter wavelengths with significantly improved tunability over a broadband wavelength *** using areal expanding and contractive strain control of dielectric elastomer actuators(DEAs)with chiral liquid crystal elastomers(CLCEs),simultaneous and omnidirectional structural color-tuning control was *** breakthrough in omnidirectional wavelength control enhances the achievable tuning freedom and versatility,making it applicable to a broad range of high-functional photonic applications.

关键词： tuning tunable directional

Iterative physical optics method based on efficient occlusion judgment with bounding volume hierarchy technology

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Journal of Electronic Science and Technology 2024年第1期22卷 1-12页

作者： Yang su Yu-Mao Wu jun Hu Key Laboratory for Information Science of Electromagnetic Waves(MoE) School of Information Science and TechnologyFudan UniversityShanghai200433China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This paper builds a binary tree for the target based on the bounding volume hierarchy technology,thereby achieving strict acceleration of the shadow judgment process and reducing the computational complexity from the original O(N^(3))to O(N^(2)logN).Numerical results show that the proposed method is more efficient than the traditional *** is verified in multiple examples that the proposed method can complete the convergence of the ***,the proposed method avoids the error of judging the lit-shadow relationship based on the normal vector,which is beneficial to current iteration and *** with the brute force method,the current method can improve the simulation efficiency by 2 orders of *** proposed method is more suitable for scattering problems in electrically large cavities and complex scenarios.

关键词： Bounding volume hierarchy Cavity scattering Iterative physical optics(IPO)

Plant regeneration in the new era:from molecular mechanisms to biotechnology applications

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Science China(Life Sciences) 2024年第7期67卷 1338-1367页

作者： Chunli Chen Yuxin Hu Momoko Ikeuchi Yuling Jiao Kalika Prasad Ying Hua su jun Xiao Lin Xu Weibing Yang Zhong Zhao Wenkun zhou Yun zhou Jian Gao Jia-Wei Wang National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China College of Life Science and Technology Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of Sciences(CAS)China National Botanical GardenBeijing 100093China Division of Biological Sciences Graduate School of Science and TechnologyNara Institute of Science and TechnologyNara 630-0192Japan State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Center for Quantitative BiologyAcademy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Indian Institute of Science Education and Research Pune 411008IndiaThiruvananthapuram 695551India State Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai’an 271018China Sino-German Joint Research Center on Agricultural Biology Shandong Agricultural UniversityTai’an 271018China Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology(IGDB)CASBeijing 100101China CAS-JIC Centre of Excellence for Plant and Microbial Science(CEPAMS) IGDBCASBeijing 100101China National Key Laboratory of Plant Molecular Genetics CEMPSInstitute of Plant Physiology and Ecology(SIPPE)CASShanghai 200032China CEPAMS SIPPECASShanghai 200032China Hefei National Laboratory for Physical Sciences at the Microscale CEMPSSchool of Life SciencesDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China Department of Botany and Plant Pathology and Center for Plant Biology Purdue UniversityWest Lafayette 47907USA School of Life Science and Technology Shang

Plants or tissues can be regenerated through various *** animal regeneration,cell totipotency and pluripotency are the molecular basis of plant *** systematic studies on Arabidopsis thaliana gradually unravel the fundamental mechanisms and principles underlying plant ***,plant hormones,cell division,epigenetic remodeling,and transcription factors play crucial roles in reprogramming somatic cells and reestablishing meristematic *** research on basal non-vascular plants and monocot crops has revealed that plant regeneration differs among species,with various plant species using distinct mechanisms and displaying significant differences in regenerative *** multi-omics studies at the single-cell level,tracking plant regeneration processes in real-time,and deciphering the natural variation in regenerative capacity will ultimately help understand the essence of plant regeneration,improve crop regeneration efficiency,and contribute to future crop design.

关键词： apical meristem model species regeneration phytohormone plant cell reprogramming somatic embryogenesis

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Protective effects and microarray-based mechanism of sea cucumber hydrolysates against high-glucose induced nephrotoxicity in mouse glomerulus mesangial cells

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未来食品学报(英文) 2024年第3期4卷 233-240页

作者： Lingxin Geng Jiaojiao Han jun zhou Ye Li Tinghong Ming Zhen Zhang Chenyang Lu Xiurong su State Key Laboratory for Quality and Safety of Argo-products School of Marine ScienceNingbo UniversityNingbo 315211China

Diabetic nephropathy(DN)is a common type of end-stage renal disease and glomerular mesangial cells(GMCs)are widely used as a cell model for *** study firstly investigated the inhibitory effects of the Apostichopus japonicus and Acaudina leucoprocta hydrolysates on cellular growth under high-glucose treatment,better inhibitory effect of *** hydrolysate was observed compared to that of *** ***,the global transcription profiles obtained via microarray analysis showed that 6070 and 7015 genes were identified in the *** and *** groups compared with the model group,*** them,transcriptions of the slc30a4,slc35dl,tppp3,tp53inpl,bcl-2,apafl,alox12b and adrala genes were restored from the levels of the model group to those of the control group,contributed to cell mitosis and proliferation in both treatment *** addition,other apoptosis-related genes,such as bcl-6,clu,foxo3 and akt,showed opposite trends between two groups,which might cause the difference in inhibitory *** preliminarily proposed that the regulation effects of *** and *** on the genes involved in cellular mitosis,proliferation and apoptosis,might contribute to their inhibitory activity on GMCs under high-glucose environment.

关键词： Diabetic nephropathy Apostichopus japonicus Acaudina leucoprocta Hydrolysate Rat mesangial cell Microarray