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PEG模拟干旱胁迫对加拿大飞蓬种子萌发及幼根生长的影响

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生物安全学报（中英文） 2024年第1期33卷 32-37页

作者：吴生海王玉莹杨春波李黎明张一杜凤国北华大学林学院吉林吉林132013 长白山特色森林资源保育与高效利用国家林业局重点实验室吉林吉林132013

【目的】研究干旱胁迫对加拿大飞蓬种子萌发及幼根生长的影响,为科学防控加拿大飞蓬入侵提供依据。【方法】以当年生加拿大飞蓬成熟种子为材料,分别用蒸馏水(CK)和不同浓度5%、10%、15%、20%、25%的聚乙二醇溶液(PEG)(分别表示轻度、中... 详细信息

【目的】研究干旱胁迫对加拿大飞蓬种子萌发及幼根生长的影响,为科学防控加拿大飞蓬入侵提供依据。【方法】以当年生加拿大飞蓬成熟种子为材料,分别用蒸馏水(CK)和不同浓度5%、10%、15%、20%、25%的聚乙二醇溶液(PEG)(分别表示轻度、中度、重度、极度和极重度干旱胁迫强度)对加拿大飞蓬种子进行处理。测定日相对发芽率、发芽率、发芽势等指标,分析加拿大飞蓬种子萌发情况;测定幼苗根系宽、根系高、根平均直径、根面积、总根尖数及根分叉数,分析其幼苗根生长情况;并测定种子恢复萌发情况。【结果】无干旱胁迫的加拿大飞蓬种子萌发指标最高,随着干旱胁迫强度增加,种子萌发指标减小,极重度干旱胁迫下加拿大飞蓬种子不萌发。与CK相比,轻度干旱胁迫和重度干旱胁迫对加拿大飞蓬根平均直径影响不显著,但会促进侧根与不定根生长;重度干旱胁迫下,加拿大飞蓬的总根尖数和分叉数显著增加。加拿大飞蓬种子在PEG浓度为20.13%的干旱胁迫下不发芽。种子在极度和极重度干旱胁迫下不萌发,但当水分条件充足时,种子依然具有萌发的能力。【结论】建议在加拿大飞蓬种子尚未成熟前进行人工拔除,或在加拿大飞蓬入侵地种植耐旱强、生长快、根系发达、竞争性强的植物,以控制加拿大飞蓬的生长发育。

关键词：加拿大飞蓬干旱胁迫种子萌发幼根生长 PEG溶液

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High Technology Letters 2019年第1期25卷 88-96页

作者： li liming Zhao Jing Yan Chaojie Wang Chunrong College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

A suitable comprehensive evaluation method for similarity comprehensive evaluation of humanoid motion(mainly to robotic arm) is *** different robotic arms, a static comprehensive evaluation model is established by projection pursuit evaluation based on indexes of humanoid robot arm motion in robotics and ergonomics field. Based on projection pursuit evaluation with timing information entropy and time degrees, a dynamic comprehensive evaluation method is proposed by linear weighting to each time's static model's indexes weight according to timing weighted vectors. Through comparing similarity comprehensive evaluation result based on static and dynamic comprehensive evaluation model, the results show that similarity based on dynamic comprehensive evaluation model is high. By comparing reliability, similarity and dispersion of static and dynamic comprehensive evaluation models, the results show that dynamic comprehensive evaluation result has better accuracy, stability and lower dispersion, and the result is more reasonable and real. Therefore, the dynamic comprehensive evaluation method proposed in this paper is more suitable for similarity comprehensive evaluation of humanoid robot arm motion.

关键词： humanoid robot arm motion similarity comprehensive evaluation projection pursuit evaluation method dynamic comprehensive evaluation method relative efficiency

2008―2018年北京城区某体检人群膳食多样化和膳食质量变化趋势

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中华疾病控制杂志 2024年第3期28卷 316-322页

作者：史洪静陈媛媛吕筠孙点剑一满塞丽麦王晓娜李立明王波余灿清北京大学公共卫生学院流行病与卫生统计学系重大疾病流行病学教育部重点实验室北京100191 北京大学医学部美年公众健康研究院北京100191 北京大学公众健康与重大疫情防控战略研究中心北京100191 北京美兆健康体检中心北京100191

目的了解2008―2018年北京城区某体检人群膳食多样化及膳食质量变化趋势。方法选择2008―2018年在北京某体检中心完成体检问卷的北京城区居民为研究对象,利用半定量食物频率问卷计算主要食物组每日摄入量,根据2010年全国人口普查数据中... 详细信息

目的了解2008―2018年北京城区某体检人群膳食多样化及膳食质量变化趋势。方法选择2008―2018年在北京某体检中心完成体检问卷的北京城区居民为研究对象,利用半定量食物频率问卷计算主要食物组每日摄入量,根据2010年全国人口普查数据中北京市≥20岁城市居民性别和年龄构成对膳食多样化评分-9分类(diet diversity score-9 classification,DDS9)和中国膳食平衡指数(Chinese diet balance index,DBI_16)的得分和指标百分率标准化,采用Meta回归分析探究变化趋势。结果共纳入224178人次,标准化后DDS9得分11年间增加0.2分,达标率从5.1%增至7.4%(P0.05)。结论2008―2018年北京市城区居民膳食摄入不足的问题有所改善,膳食摄入过量的问题逐年加重,膳食多样化状况不佳。应采取干预措施指导居民理解膳食多样化、促进居民膳食均衡、提高膳食质量。

关键词：膳食质量膳食多样化长期变化趋势

Modulation of Spike Count Correlations Between Macaque Primary Visual Cortex Neurons by Difficulty of Attentional Task

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Neuroscience Bulletin 2022年第5期38卷 489-504页

作者： Qiyi Hu Wenjuan Hu Keyi liu Xiangdong Bu lisha Hu liming li Xinyu Chai Yao Chen School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Studies have shown that spatial attention remarkably affects the trial-to-trial response variability shared between *** in the attentional task adjusts how much concentration we maintain on what is currently important and what is filtered as irrelevant sensory ***,how task difficulty mediates the interactions between neurons with separated receptive fields(RFs)that are attended to or attended away is still not *** examined spike count correlations between single-unit activities recorded simultaneously in the primary visual cortex(V1)while monkeys performed a spatial attention task with two levels of ***,the RFs of the two neurons recorded were non-overlapping to allow us to study fluctuations in the correlated responses between competing visual inputs when the focus of attention was allocated to the RF of one *** increasing difficulty in the spatial attention task,spike count correlations were either decreased to become negative between neuronal pairs,implying competition among them,with one neuron(or none)exhibiting attentional enhancement of firing rate,or increased to become positive,suggesting inter-neuronal cooperation,with one of the pair showing attentional suppression of spiking ***,the modulation of spike count correlations by task difficulty was independent of the attended *** findings provide evidence that task difficulty affects the functional interactions between different neuronal pools in V1 when selective attention resolves the spatial competition.

关键词： Rhesus monkey Spatial attention Shared variability Attentional load Primary visual cortex

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营养支持专科护士临床教学基地建设的探索

中华护理教育 2024年第7期21卷 801-807页

作者：陶琳易银萍蒋秋焕张红梅李黎明荆婵杜晓宁河南省人民医院郑州市450000

营养支持专科护士培训是培养临床营养高级护理实践人才的重要举措。河南省人民医院作为首批中华护理学会营养支持专科护士京外临床教学基地,通过完善软硬件设施,从组织管理、制度建设、师资管理、培训实施、培训保障和质量控制6个方面... 详细信息

营养支持专科护士培训是培养临床营养高级护理实践人才的重要举措。河南省人民医院作为首批中华护理学会营养支持专科护士京外临床教学基地,通过完善软硬件设施,从组织管理、制度建设、师资管理、培训实施、培训保障和质量控制6个方面建设培训管理体系,初步形成较为合理的营养支持专科护士临床实践培训模式,在师资队伍建设、人才培养、科研创新等方面均取得较好成效。

关键词：营养支持教育护理在职培训专科护士

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阴离子交换膜在电解水制氢领域的研究进展

河南化工 2024年第9期41卷 36-39页

作者：白佳凯张安然李朋喜乔东伟李黎明中船(邯郸)派瑞氢能科技有限公司河北邯郸056010

综述了阴离子交换膜的离子电导率与碱稳定性,对阴离子交换膜的离子传输机制以及降解机制进行了分析,总结了对于离子电导率与碱稳定性的改进策略。对用于电解水制氢技术的阴离子交换膜后续研究提出了展望,为阴离子交换膜电解水制氢技术... 详细信息

综述了阴离子交换膜的离子电导率与碱稳定性,对阴离子交换膜的离子传输机制以及降解机制进行了分析,总结了对于离子电导率与碱稳定性的改进策略。对用于电解水制氢技术的阴离子交换膜后续研究提出了展望,为阴离子交换膜电解水制氢技术实现大规模商业化应用提供理论指导。

关键词：电解水技术阴离子交换膜电解水技术阴离子交换膜碱稳定性

Rapid and effective treatment of traumatic spinal cord injury using stem cell derived exosomes

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Asian Journal of Pharmaceutical Sciences 2021年第6期16卷 806-815页

作者： Jiafu Mu Jiahe Wu Jian Cao Teng Ma liming li Shiqing Feng Jianqing Gao College of Pharmaceutical Sciences Zhejiang UniversityHangzhou 310058China Pilot National Laboratory for Marine Science and Technology Qingdao 266137China Department of Orthopedics Tianjin Medical University General HospitalTianjin 300052China International Science and Technology Cooperation Base of Spinal Cord Injury Tianjin Key Laboratory of Spine and Spinal Cord InjuryDepartment of OrthopedicsTianjin Medical University General HospitalTianjin 300052China Dr.li Dak Sum&Yip Yio Chin Center for Stem Cell and Regenerative Medicine Zhejiang UniversityHangzhou 310058China

Traumatic spinal cord injury is a fatal acute event without effective clinical *** the trauma,immediate neural protection and microenvironment mitigation are vitally important for nerve tissue repair,where stem cell-based therapies could be eclipsed by the deficiency of cells due to the hostile microenvironment as well as the transport and preservation *** emergency strategies are required to be convenient,biocompatible,and ***,we assess an emergency cell-free treatment using mesenchymal stem cell-derived exosomes,which have proven capable of comprehensive mitigation of the inhibitory lesion *** clinically validated fibrin glue is utilized to encapsulate the exosomes and in-situ gelates in transected rat spinal cords to provide a substrate for exosome delivery as well as nerve tissue *** emergency treatment alleviates the inflammatory and oxidative microenvironment,inducing effective nerve tissue repair and functional *** therapy presents a promising strategy for effective emergency treatment of central nervous system trauma。

关键词： Exosome Fibrin glue Spinal cord injury Emergency treatment

Study on detecting main ingredients of silicone rubber based on terahertz spectrum

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High Voltage 2024年第3期9卷 518-527页

作者： Hongwei Mei Lanxin li Fanghui Yin liming Wang Masoud Farzaneh Shenzhen International Graduate School(SIGS) Tsinghua UniversityShenzhenGuangdongChina Kunming Power Exchange Center KunmingYunnanChina Department of Applied Sciences(DSA) University of Quebec at ChicoutimiChicoutimiQuebecCanada

The authors investigated the ingredient detection technique of silicone rubber based on the Terahertz *** this purpose,18 diverse high-temperature vulcanised silicone rubber(HTVSR)formulations were customised,8 of which are used as calibration set while the rest 10 as prediction *** on the Beer-Lambert Law,the partial-least-square(PLS)regression model and the least-squares support-vector machines(LS-SVM)regression model were used to yield the relationships between the absorption spectrums and the content percentages of polydimethylsiloxane(PDMS),alumina tri-hydrate(ATH),and silica in *** results showed that for the formulations tested,the prediction accuracy of all three main ingredients by the PLS regression model could be improved by changing the spectrum range from 0.2–4 to 0.5–2 *** the data were pre-processed by the Savitzky–Golay smoothing method or multiplicative scatter correction method,the prediction accuracy of PDMS could be further ***,this would lead to a slight decrease in the prediction accuracy of *** the LS-SVM regression model,the radial basis function(RBF)kernel and the linear kernel were *** was found that the prediction accuracy of both kernels was better than that of the PLS regression *** the LS-SVM regression model using the RBF kernel,the correlated coefficients of PDMS and ATH in the prediction set could be up to 0.9915 and 0.9742,respectively.

关键词： rubber spectrum kernel

Pd(I)-catalyzed ring-opening arylation of cyclopropyl-α-aminoamides:Access toα-ketoamide peptidomimetics

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Chinese Chemical Letters 2024年第6期35卷 320-326页

作者： Yue Sun liming Yang Yaohang Cheng Guanghui An Guangming li School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-*** protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product *** selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal *** investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.

关键词： Pd(I)catalysis Ring-opening arylation Domino reactions Oligopeptides Late-stage functionalization