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Effect of pre-existing shear bands on mechanical properties and serration behaviors in bulk metallic glasses

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Journal of Iron and Steel Research(International) 2017年第4期24卷 402-410页

作者： xu-dong yuan Sheng-hai Wang Kai-kai Song Xiao-liang Han Yu-sheng Qin dong-fang Li xue-lian Li Bo Song Hui Xing Li Wang School of Mechanical Electrical &Information EngineeringShandong University(Weihai) School of Science Northwestern Polytechnical University

Pre-existing（multiple）shear bands were introduced into the ductile Zr56Co28Al16 and Zr65Ni10Cu15Al10bulk metallic glasses（BMGs）through the lateral-deformation,respectively.It was found that the pre-exiting shear bands can further enhance the compressive plasticity of ductile BMGs.According to the serration analysis on the plastic deformation of the as-cast and the pre-deformed samples,the serration events in the stress-strain curves during deformation display a self-organized critical（SOC）behavior.Compared with the as-cast BMGs,a larger power-law scaling exponent calculated based on serrated flow behaviors becomes larger for the pre-deformed BMGs,implying that the shear banding stability of BMGs is effectively enhanced.This should be caused by the pronounced interactions of shear bands during plastic deformation for the pre-deformed BMGs.However,by introducing a large amount of multiple shear bands into the glassy matrix,it also becomes easier for shear bands to propagate along the pre-existing shear bands,leading to a lower cut-off elastic energy density for the pre-deformed BMGs.More multiple shear bands with stronger interactions for the pre-deformed BMGs could provide a larger chance to activate the shear-band cracking but less local elastic energies are remained for the subsequent crack-linking.

关键词： Bulk metallic glass Shear band Serration Ductility Pre-deformation

基于人工神经网络的狼尾草属牧草品质近红外光谱预测研究

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草地学报 2024年第2期32卷 527-534页

作者：朱瑞芬徐远东孙万斌刘畅姚博陈积山重庆市畜牧科学院重庆402460 重庆市草业工程技术研究中心重庆402460

本研究利用近红外光谱通过人工神经网络(Artificial neural network, ANN)建立狼尾草属(Pennisetum Rich)牧草水分、粗蛋白、木质素、酸性/中性洗涤纤维及灰分含量的预测模型。结果表明:基于人工神经网络的狼尾草属牧草品质预测模型总... 详细信息

本研究利用近红外光谱通过人工神经网络(Artificial neural network, ANN)建立狼尾草属(Pennisetum Rich)牧草水分、粗蛋白、木质素、酸性/中性洗涤纤维及灰分含量的预测模型。结果表明:基于人工神经网络的狼尾草属牧草品质预测模型总体优于全光谱偏最小二乘法(PLS)模型效果。在人工神经网络的方向传播(BP)网络模型中,6项表征牧草品质指标的校正均方根误差(RMSEC)、预测均方根误差(RMSEP)均显著低于PLS模型,同时校正集决定系数(R_(C)^(2))、预测集决定系数(R_(P)^(2))显著提高,除灰分含量预测不理想外,其他预测效果均理想。同时人工神经网络的BP网络对于近红外光谱的非线性数据具有良好的拟合能力,其预测模型对于指导狼尾草属牧草品质预测和分级管理研究具有广阔的应用前景。

关键词：狼尾草属常规营养成分近红外光谱人工神经网络

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36份马棘种质资源抗旱性评价

西南农业学报 2024年第3期37卷 542-551页

作者：陈静何玮徐远东刘畅马慧珍孙万斌范彦重庆市畜牧科学院/重庆市草业工程技术研究中心/重庆市作物种质荣昌牧草资源库重庆402460 青海大学西宁810016

【目的】分析不同程度的干旱胁迫处理对马棘生理指标的影响,探索其抗旱生理响应特征,为马棘抗旱种质筛选和遗传改良提供参考依据。【方法】以重庆地区广泛收集的36份野生马棘种质资源为试验材料,采用盆栽培养的方式待马棘幼苗生长至第9... 详细信息

【目的】分析不同程度的干旱胁迫处理对马棘生理指标的影响,探索其抗旱生理响应特征,为马棘抗旱种质筛选和遗传改良提供参考依据。【方法】以重庆地区广泛收集的36份野生马棘种质资源为试验材料,采用盆栽培养的方式待马棘幼苗生长至第90天时开始干旱处理,分别在胁迫0 d(对照组CK,土壤相对含水量为田间持水量的80%~85%)、胁迫7 d(中度干旱,土壤含水量为田间持水量的40%~50%)和胁迫14 d(重度干旱,土壤相对含水量为田间持水量的20%~25%)时测定各处理下马棘叶片的渗透调节物质含量、相对含水量和抗氧化酶活性,利用抗旱系数结合隶属函数和聚类分析法对马棘的抗旱性进行综合评价。【结果】在干旱胁迫下,36份马棘种质的生理响应变异丰富,不同种质的抗旱能力差异显著。通过对同一指标的均值比较分析发现,与对照相比,渗透调节物质丙二醛(MDA)、可溶性蛋白(SP)和脯氨酸(Pro)含量随着干旱程度增加而上升;超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性随着干旱程度增加而呈“凸”字形变化;相对含水量(RWC)随着干旱程度增加而降低。7个检测指标中,POD活性的变异系数最大,而RWC的变异系数最小。通过隶属函数、综合D值和聚类分析可将36份马棘种质的抗旱能力分为抗旱型(8份种质)和敏感型(28份种质)两类。通过对两种类型种质的生理指标分析发现,抗旱型种质的抗氧化酶活性和渗透调节物质Pro含量高于敏感型种质。【结论】干旱胁迫下36份马棘种质资源的生理响应具有丰富的多样性和变异,通过综合评价分析初步筛选出8份抗旱型马棘种质。

关键词：马棘干旱胁迫种质资源评价抗旱性生理响应

Microglial Calcium Homeostasis Modulator 2:Novel Anti-neuroinflammation Target for the Treatment of Neurodegenerative Diseases

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Neuroscience Bulletin 2024年第4期40卷 553-556页

作者： yuan dong Li Tang Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao UniversityQingdao266000China Qingdao Institute of Measurement Technology Qingdao266000China

Neurodegenerative diseases,including Alzheimer's disease(AD)and Parkinson's disease(PD),are the most common causes of dementia.Current drugs for such diseases can only provide temporary help with the symptoms,leaving the discovery of new drugs urgently in need.Microglial cells are the local immune cells in the nervous system and have been recognized as the key player in neuroinflammation that contributes to the process of neurodegeneration[1],raising the discussion of aiming microglia as the therapeutic target for clinical treatment of neurodegenerative diseases.

关键词： inflammation degenerative drugs

Effectively improving the extreme-pressure capacity of a class of intercalated zirconium phosphate materials

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Science China(Technological Sciences) 2024年第3期67卷 753-764页

作者： NIU WenXing ZHAO XinRui yuan Min HOU ZhiGuo LIU Lei xu Hong dong JinXiang Shanxi Key Laboratory of Chemical Product Engineering Cllege of Chemical Engineering and TechnologyTaiyuan University of TechnologyTaiyuan 030024China School of Chemical and Environmental Engineering Pingdingshan UniversityPingdingshan 467000China

We studied different long-chain ammonium ions intercalated zirconium phosphate α-ZrP, methylamine intercalated ZrP(MAZrP), tetramethylammonium hydroxide intercalated ZrP(TMAH-ZrP), dodecyltrimethylammonium bromide intercalated ZrP(DTAB-ZrP), and stearyl trimethyl ammonium bromide intercalated ZrP(STAB-ZrP) as grease co-additives in combination with isobutylene sulfide(SIB). The grease with co-additives displayed excellent extreme-pressure and anti-wear performance.Moreover, the combination of the longest chain ammonium ion intercalated zirconium phosphate, STAB-ZrP/SIB, had the best tribological properties. In comparison to α-ZrP, the advantage of STAB-ZrP was that it did not form a large area of the dense physical film like α-ZrP on the worn surface, but rather gave the SIB a chance to contact with the fresh metal surface to generate a chemical film. Therefore, the sub-micron physical film and nanoscale chemical film always exist side by side on the contact surface during the friction process. This intercalated α-ZrP/SIB additive has great potential for use in harsh operating conditions.

关键词： intercalatedα-ZrP/SIB physical film chemical film tribological properties

Translation machinery: the basis of translational control

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Journal of Genetics and Genomics 2024年第4期51卷 367-378页

作者： Shu yuan Guilong Zhou Guoyong xu State Key Laboratory of Hybrid Rice Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China Hubei Hongshan Laboratory WuhanHubei 430070China

Messenger RNA(mRNA)translation consists of initiation,elongation,termination,and ribosome recycling,carried out by the translation machinery,primarily including tRNAs,ribosomes,and translation factors(TrFs).Translational regulators transduce signals of growth and development,as well as biotic and abiotic stresses,to the translation machinery,where global or selective translational control occurs to modulate mRNA translation efficiency(TrE).As the basis of translational control,the translation machinery directly determines the quality and quantity of newly synthesized peptides and,ultimately,the cellular adaption.Thus,regulating the availability of diverse machinery components is reviewed as the central strategy of translational control.We provide classical signaling pathways(e.g.,integrated stress responses)and cellular behaviors(e.g.,liquideliquid phase separation)to exemplify this strategy within different physiological contexts,particularly during hostemicrobe interactions.With new technologies developed,further understanding this strategy will speed up translational medicine and translational agriculture.

关键词： Translational control Ribosome tRNA Translation machinery uORF Phase separation Immune response

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese Journal of Natural Medicines 2024年第2期22卷 161-170页

作者： SUN Zeshi LIN Shan WU Zhi-Li dong Hong-yuan xu Xi-Ke LI Hui-Liang WANG Jinxin School of Pharmacy Second Military Medical UniversityShanghai 200433China State Key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Our continued works on the chemical constituents of Ginkgo biloba(G.biloba)leaves has led to the isolation of two novel phenylbutenoids(1,2),along with five previously unidentified terpene glycosides(3−7).Among them,compounds 1 and 2 represent unique(Z)-phenylbutenoids,3−6 are megastigmane glycosides,and 7 is identified as a rare bilobanone glycoside(Fig.1).This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from G.biloba.The chemical structures of these compounds were elucidated through extensive spectroscopic analysis,including HR-ESI-MS and various 1D and 2D NMR experiments.Furthermore,the absolute configurations of these molecules were determined using Mosher’s method,ECD experiments,and Cu-KαX-ray crystallographic analyses.

关键词： Ginkgo biloba Phenylbutenoid Megastigmane glycoside Bilobanone glycoside

Claudin 18.2 is a potential therapeutic target for zolbetuximab in pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2022年第7期14卷 1252-1264页

作者： Xi Wang Cheng-Sheng Zhang xu-yuan dong yuan Hu Bao-Jun Duan Jun Bai Yin-Ying Wu Lin Fan Xin-Hua Liao Ye Kang Peng Zhang Meng-Yang Li Jiao xu Zhi-Jun Mao Hui-Tong Liu Xiao-Long Zhang Li-Fei Tian En-Xiao Li Department of Medical Oncology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Medical Oncology Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina Department of Cancer Precision Medicine Med-X InstituteThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Cancer Center The First Affiliated Hospital of Xi'an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of General Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of General Surgery Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina Department of Orthopedics Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is frequently diagnosed and treated in advanced tumor stages with poor prognosis.More effective screening programs and novel therapeutic means are urgently needed.Recent studies have regarded tight junction protein claudin 18.2(CLDN18.2)as a candidate target for cancer treatment,and zolbetuximab(formerly known as IMAB362)has been developed against CLDN18.2.However,there are few data reported thus far related to the clinicopathological characteristics of CLDN18.2 expression for PDAC.AIM To investigate the expression of CLDN18.2 in PDAC patients and subsequently propose a new target for the treatment of PDAC.METHODS The Cancer Genome Atlas,Genotype-Tissue Expression,Gene Expression Omnibus,and European Genome-phenome Archive databases were first employed to analyze the CLDN18 gene expression in normal pancreatic tissue compared to that in pancreatic cancer tissue.Second,we analyzed the expression of CLDN18.2 in 93 primary PDACs,86 para-cancer tissues,and 13 normal pancreatic tissues by immunohistochemistry.Immunostained tissues were assessed applying the histoscore.subsequently,they fell into two groups according to the expression state of CLDN18.2.Furthermore,the correlations between CLDN18.2 expression and diverse clinicopathological characteristics,including survival,were investigated.RESULTS The gene expression of CLDN18 was statistically higher(P<0.01)in pancreatic tumors than in normal tissues.However,there was no significant correlation between CLDN18 expression and survival in pancreatic cancer patients.CLDN18.2 was expressed in 88(94.6%)of the reported PDACs.Among these tumors,50(56.8%)cases showed strong immunostaining.The para-cancer tissues were positive in 81(94.2%)cases,among which 32(39.5%)of cases were characterized for strong staining intensities.Normal pancreatic tissue was identified solely via weak immunostaining.Finally,CLDN18.2 expression significantly correlated with lymph node metastasis,distant metastasis,nerve invasion,stage,and survival of

关键词： Pancreatic ductal adenocarcinoma Claudin 18.2,Immunohistochemistry Therapeutic target Diagnosis Prognosis

Photonic neuromorphic architecture for tens-of-task lifelong learning

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Light(Science & Applications) 2024年第3期13卷 519-530页

作者： yuan Cheng Jianing Zhang Tiankuang Zhou Yuyan Wang Zhihao xu Xiaoyun yuan Lu Fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing 100084China Institute for Brain and Cognitive Science Tsinghua University(THUIBCS)Beijing 100084China

Scalable,high-capacity,and low-power computing architecture is the primary assurance for increasingly manifold and large-scale machine learning tasks.Traditional electronic artificial agents by conventional power-hungry processors have faced the issues of energy and scaling walls,hindering them from the sustainable performance improvement and iterative multi-task learning.Referring to another modality of light,photonic computing has been progressively applied in high-efficient neuromorphic systems.Here,we innovate a reconfigurable lifelong-learning optical neural network(L2 ONN),for highly-integrated tens-of-task machine intelligence with elaborated algorithm-hardware codesign.Benefiting from the inherent sparsity and parallelism in massive photonic connections,L2 ONN learns each single task by adaptively activating sparse photonic neuron connections in the coherent light field,while incrementally acquiring expertise on various tasks by gradually enlarging the activation.The multi-task optical features are parallelly processed by multi-spectrum representations allocated with different wavelengths.Extensive evaluations on freespace and on-chip architectures confirm that for the first time,L2 ONN avoided the catastrophic forgetting issue of photonic computing,owning versatile skills on challenging tens-of-tasks(vision classification,voice recognition,medical diagnosis,etc.)with a single model.Particularly,L2 ONN achieves more than an order of magnitude higher efficiency than the representative electronic artificial neural networks,and 14×larger capacity than existing optical neural networks while maintaining competitive performance on each individual task.The proposed photonic neuromorphic architecture points out a new form of lifelong learning scheme,permitting terminal/edge AI systems with light-speed efficiency and unprecedented scalability.

关键词： life neural versatile