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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 Micro-Nano α-Al2O3 Waterborne Polyurethane Resin Particle Size Surface Hardness Corrosion Resistance
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Synthesis and Characterization of β-Cyclodextrin Modified Biochar Environmental Remediation Materials
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作者 Qing Guo Xiao Wang +3 位作者 Wanke Chen Xiaoyan Wang jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第4期42-52,共11页
In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cy... In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cyclodextrin (β-CD) was used to modify biochar (BC). The prepared modified biochar materials were labeled with β-CDBC, β-CDBC-Na, β-CDBC-CA and β-CDBC-H, respectively. The infrared spectrum, X-ray diffractometer, scanning electron microscope and specific surface area of the four modified materials were tested. The results showed that the C-O stretching vibration peak at 1020 cm<sup>−</sup><sup>1</sup> of the modified materials was slightly offset compared with that of biochar. The characteristic absorption peaks of XRD pattern decrease obviously at 2θ = 26.7˚ and 29.5˚. It can be obviously observed on the electron microscope image that the surface is loaded or formed clathrates, and BET data and graphs also show that the specific surface area of the modified biochar is larger. Therefore, β-cyclodextrin successfully modified biochar and formed clathrates on the surface of biochar or was loaded in the pore structure of biochar, especially β-CDBC-CA achieved better modification effect. Because biochar and β-cyclodextrin raw materials are cheap, easy to prepare and green, and less prone to secondary pollution, it has a good advantage in environmental governance. 展开更多
关键词 BIOCHAR Β-CYCLODEXTRIN MODIFICATION CLATHRATE Green Environmental Protection
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Feasibility Analysis of the Sintering Flue Gas Oxidation Method for Denitrification Technology Route
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作者 Weiling Chu Linling Wu +1 位作者 jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第6期12-23,共12页
With the vigorous development of China’s iron and steel industry and the introduction of ultra-low emission policies, the emission of pollutants such as SO2 and NOx has received unprecedented attention. At present, t... With the vigorous development of China’s iron and steel industry and the introduction of ultra-low emission policies, the emission of pollutants such as SO2 and NOx has received unprecedented attention. At present, the commonly used denitrification methods include selective catalytic reduction (SCR), active coke, etc. As a newly developed denitrification technology, oxidation denitrification is not widely used, and the technical level is mixed, and there might be problems such as yellow smoke, secondary pollution and ozone escape in the practical application. In this paper, problems existing in the denitrification process of sintering flue gas oxidation are analyzed, and a 320 m2 sintering machine is taken as an example. Comparing the denitrification technology of sintering industry, it could be seen that the denitrification technology route of oxidation method has low pollution, low cost and high comprehensive environmental benefits, and has greatly potential development. 展开更多
关键词 SINTERING Air Pollution Denitration by Oxidation
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我国静电纺丝领域研究现状及其热点:基于CNKI数据库的可视化文献计量分析 被引量:6
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作者 苏芳芳 经渊 +1 位作者 宋立新 唐志荣 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第1期45-54,共10页
基于CNKI数据库,利用CiteSpace可视化计量学方法分析国内静电纺丝领域的发文量、作者和机构合作状况以及研究主题的演化,并与国际上2018-2022年的研究主题进行对比。分析发现:国内作者在静电纺丝领域的发文量呈现逐年增加趋势;作者共现... 基于CNKI数据库,利用CiteSpace可视化计量学方法分析国内静电纺丝领域的发文量、作者和机构合作状况以及研究主题的演化,并与国际上2018-2022年的研究主题进行对比。分析发现:国内作者在静电纺丝领域的发文量呈现逐年增加趋势;作者共现的局部网络密度大,整体网络密度小;参与静电纺丝研究的高校之间合作密切;国内静电纺丝领域的研究主要集中在纤维的制备,及纳米纤维在生物医药、空气过滤、水处理、能源器件、防护、传感等领域的应用等方面,与国际上在静电纺丝领域的研究热点有较高的相似性。 展开更多
关键词 静电纺丝 文献计量 可视化 纳米纤维 CITESPACE
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中国人群33104例单基因病携带者筛查的多中心研究
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作者 侯伟 付晓琳 +17 位作者 谢潇潇 张春燕 边佳昕 毛翛 文娟 罗春玉 金华 祝茜 戚庆炜 钱叶青 袁静 赵彦艳 尹爱兰 李树铁 蒋宇林 张蔓丽 肖锐 卢彦平 《南方医科大学学报》 CAS CSCD 北大核心 2024年第6期1015-1023,共9页
目的 通过大规模多中心的多种遗传病携带者筛查,调查中国人群单基因病的流行病学特征以及突变谱,为制定适合中国人群的遗传病预防策略提供依据。方法 本研究在中国的12个临床中心共招募33 104例受检者(16 610例女性),基于高通量测序和多... 目的 通过大规模多中心的多种遗传病携带者筛查,调查中国人群单基因病的流行病学特征以及突变谱,为制定适合中国人群的遗传病预防策略提供依据。方法 本研究在中国的12个临床中心共招募33 104例受检者(16 610例女性),基于高通量测序和多种PCR对223个基因的携带者状态进行检测。结果 197个常染色体基因的合并携带者频率为55.58%,26个X连锁基因的合并携带者频率为1.84%。在16 669例家系中,共检出874对(5.24%)高危夫妇。其中常染色体基因高危夫妇584对(3.50%),X连锁基因高危夫妇306对(1.84%),16对夫妇同时为常染色体基因和X连锁基因高危夫妇。最常检出的常染色体高危基因包括GJB2(常染色体隐性耳聋1A,393对),HBA1/HBA2(α-地中海贫血,36对)和PAH(苯丙酮尿症,14对),SMN1(脊髓性肌萎缩症,14对)。最常检出的X连锁高危基因包括G6PD(G6PD缺乏症,236对),DMD(进行性假肥大性肌营养不良,23对)和FMR1(脆性X综合征,17对)。除外G6PD后的高危夫妇率为3.91%(651/16 669),进一步除外GJB2 c.109G>A位点后,高危夫妇率为1.72%(287/16 669)。理论上严重的单基因病出生缺陷的发病率约为4.35‰(72.5/16 669)。对导致高危夫妇最多的22个基因进行筛查可检出95%以上的高危夫妇,对导致高危夫妇最多的54个基因进行筛查可检出99%以上的高危夫妇。结论 本研究揭示了我国人群中223种单基因病的携带者频率,为中国人群的携带者筛查策略制定和panel设计提供依据。在携带者筛查实践中,针对某些特殊基因或变异位点的遗传咨询可能会面临困难。这些特殊基因或变异需要在检测前告知受检夫妇,并在可能的情况下提供不筛查这些基因或变异的选择。 展开更多
关键词 携带者筛查 单基因病 遗传咨询
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基于核心素养的高校英语教学的创新发展研究
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作者 李梦洋 井媛 +1 位作者 陈耀庭 杨坤 《湖北开放职业学院学报》 2024年第11期6-8,共3页
英语是现阶段高校教学实践中说道普遍关注的学科之一,分析研究英语的教学目标和方向,并对英语教学的创新发展做分析与讨论,这对于推进英语教学改革,提升英语教学实效有突出的现实意义。目前,核心素养教育理念越来越深入人心,在核心素养... 英语是现阶段高校教学实践中说道普遍关注的学科之一,分析研究英语的教学目标和方向,并对英语教学的创新发展做分析与讨论,这对于推进英语教学改革,提升英语教学实效有突出的现实意义。目前,核心素养教育理念越来越深入人心,在核心素养教育的具体要求下,高校的英语教学需要做积极的调整,包括教学方法的调整、教学模式的调整、教学目标的调整等。总的来讲,对核心素养背景下的高校英语教学发展目标进行明确,并在目标基础上强调英语教学的创新发展策略,这对于指导当前教育有突出现实价值。文章基于核心素养分析高校英语教学的创新发展,旨在为当前教育实践提供参考与帮助。 展开更多
关键词 核心素养 高校 英语教学 创新发展
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天然次生林中小斑啄木鸟的取食偏好
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作者 荆媛 魏爽 +3 位作者 史文辉 马梓贺 王德宇 戎可 《野生动物学报》 北大核心 2024年第1期84-94,共11页
2022年3—6月,于黑龙江帽儿山森林生态系统国家野外科学观测研究站开展小斑啄木鸟(Dryobates minor)取食偏好的调查。采用样方结合样线与无线电追踪技术追踪小斑啄木鸟,采用基于“利用-可利用型”方法的Bailey’s方法分析小斑啄木鸟取... 2022年3—6月,于黑龙江帽儿山森林生态系统国家野外科学观测研究站开展小斑啄木鸟(Dryobates minor)取食偏好的调查。采用样方结合样线与无线电追踪技术追踪小斑啄木鸟,采用基于“利用-可利用型”方法的Bailey’s方法分析小斑啄木鸟取食树木与取食生境的偏好,采用主成分分析归纳影响选择取食地的主要因子,利用Fisher’s精确检验、非参数检验和相关性检验探究性别在取食行为中及主要因子间的差异。结果显示:小斑啄木鸟偏好在活立木上,用轻啄的方式,在冠层处、侧枝上短时取食;株密度、取食树高度、坡度、优势种、最近人为干扰距离与样方内树的均高是影响小斑啄木鸟选择取食树木与取食生境的主要因子;小斑啄木鸟偏好在株密度适中、取食树的高度约15 m、平坡处、以春榆(Ulmus davidiana var.japonica)或胡桃楸(Juglans mandshurica)为优势种、靠近人为干扰和样方内树均高约13 m的生境内取食;与雌性相比,雄性还偏好在株密度较低、株高在3~5 m的树木上取食。 展开更多
关键词 小斑啄木鸟 取食偏好 取食行为 取食树木 取食生境
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阔叶红松林中黑啄木鸟的取食生境偏好
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作者 于美辰 陈俊达 +3 位作者 司雨蕙 魏爽 荆媛 戎可 《野生动物学报》 北大核心 2024年第2期328-337,共10页
2020年冬季—2022年冬季,采用样线法和样方法对黑龙江省凉水国家级自然保护区中黑啄木鸟(Dryocopus martius)取食生境偏好进行调查研究,结果表明:在取食微生境尺度中,黑啄木鸟取食树树种、取食树状态与对照样方具有显著差异(p<0.05)... 2020年冬季—2022年冬季,采用样线法和样方法对黑龙江省凉水国家级自然保护区中黑啄木鸟(Dryocopus martius)取食生境偏好进行调查研究,结果表明:在取食微生境尺度中,黑啄木鸟取食树树种、取食树状态与对照样方具有显著差异(p<0.05),偏好在冷杉(Abies fabri,47.71%)和半枯立木(73.86%)的树木主干(86.93%)中上部(43.14%)、上部(32.03%)取食,且偏好粗壮、高大的树木;在取食样方尺度中,黑啄木鸟偏好在有林窗(92.16%)的天然林(96.73%)中取食,偏好郁闭度较低、优势乔木均高较低、优势乔木平均胸径较大、样方中活立木较少、枯立木、倒木较多和距人为干扰更近的生境中取食,与对照样方呈显著差异(p<0.05)。资源选择函数结果表明,影响黑啄木鸟取食生境偏好的关键因子是取食树树种,次关键因子是枯立木数量、优势乔木均高、取食树高度和倒木数量。 展开更多
关键词 黑啄木鸟 取食生境偏好 阔叶红松林 资源选择函数
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基于“气血和”探析关元穴延缓皮肤衰老的作用
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作者 惠倩倩 童伯瑛 +1 位作者 靖媛 游世晶 《内蒙古中医药》 2024年第5期139-141,共3页
气血作为人体生命活动的最基本物质,对人体各脏腑组织器官起着温煦、防御、气化及营养、滋润的作用。气血充足则筋骨强健,肌肉丰满,面色润泽,反应敏捷,气血失和则百病皆生。关元穴作为任脉腧穴,足三阴、阳明、任脉之会,可补气益血,调理... 气血作为人体生命活动的最基本物质,对人体各脏腑组织器官起着温煦、防御、气化及营养、滋润的作用。气血充足则筋骨强健,肌肉丰满,面色润泽,反应敏捷,气血失和则百病皆生。关元穴作为任脉腧穴,足三阴、阳明、任脉之会,可补气益血,调理冲任,保健强壮。当机体皮肤出现衰老现象时,从调和气血入手,使“气血和”以充分荣养、滋润于皮肤,令皮肤荣润细腻、富有光泽。 展开更多
关键词 气血 关元穴 皮肤衰老
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场景视角下的集镇公共空间更新——以新昌县儒岙镇共富风貌驿设计为例
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作者 王天玺 郑军 +3 位作者 叶欣 景远 张昱展 杨占超 《浙江建筑》 2024年第1期76-80,共5页
集镇公共空间是承载镇民日常生产生活的核心空间,也是展现新时代乡镇风貌与共同富裕成果的重要窗口。现从场景营造视角出发,在场地、场所与场景三个维度参照下探索乡镇公共空间更新改造场地价值发掘、人本场所建构、场景活力塑造策略。... 集镇公共空间是承载镇民日常生产生活的核心空间,也是展现新时代乡镇风貌与共同富裕成果的重要窗口。现从场景营造视角出发,在场地、场所与场景三个维度参照下探索乡镇公共空间更新改造场地价值发掘、人本场所建构、场景活力塑造策略。并结合新昌县儒岙镇共富风貌驿设计,系统阐明了更具特色、更有温度的集镇公共空间更新路径,可为当代集镇公共空间更新设计提供有益的思路。 展开更多
关键词 集镇公共空间 旧城更新 共富风貌驿
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金属-有机框架材料在超级电容器中的优势和进展
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作者 卢春宇 井源 +4 位作者 魏晓飞 姚世伟 王智飞 王姝斌 戴昉纳 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第2期1-15,共15页
金属-有机框架(Metal-organic framework,MOF)材料因其出色的比表面积、众多的活性位点、可调的孔径范围和灵活的框架结构,在气体分离、储能和催化等领域发挥着重要的作用.近年来,采用高表面积、永久孔隙以及包含固有的氧化还原活性位点... 金属-有机框架(Metal-organic framework,MOF)材料因其出色的比表面积、众多的活性位点、可调的孔径范围和灵活的框架结构,在气体分离、储能和催化等领域发挥着重要的作用.近年来,采用高表面积、永久孔隙以及包含固有的氧化还原活性位点的MOF材料作为超级电容器的电极材料引起了研究者们的关注.本文主要从MOF在超级电容器领域的研究出发,着重介绍了其性能和结构对超级电容器电化学性能的影响,阐述了关于MOF性能调控和结构设计的研究进展.首先,MOF的电导率是影响超级电容器能量密度和功率密度的一大关键性能,而其材料的特殊结构又直接影响了导电率.其次,MOF丰富的活性位点和可调的孔径尺寸等特点都为其导电性能的提升创造了条件.此外,MOF的结构稳定性与超级电容器的循环性能密切相关,稳定结构的构建是增强超级电容器循环性能的重要前提.最后,对MOF未来在超级电容器领域中的研究进行了展望,结构的调控仍然是这一领域的重要研究方向. 展开更多
关键词 金属-有机框架材料 超级电容器 导电率 稳定性 结构调控
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Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific
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作者 Yachang Cheng Lei Zhu +6 位作者 Lin Xue Shisheng Ma Nan Jia Shaoping Zang Zhihai Cao jing yuan Yang Liu 《Avian Research》 SCIE CSCD 2024年第1期27-34,共8页
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to... Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel. 展开更多
关键词 Behavioral strategy BIOLOGGING Central place foraging Marine primary productivity Seabird Sea surface temperature
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Fracturing timing of Jurassic reservoirs in the Dibei-Tuziluoke gas field,Kuqa foreland basin:Evidence from petrography,fluid inclusions,and clumped isotopes
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作者 Guoding Yu Wenfang yuan +6 位作者 Kelai Xi Yin Liu Shuai Wang Zhenping Xu jing yuan Lu Zhou Keyu Liu 《Energy Geoscience》 EI 2024年第2期129-140,共12页
Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clu... Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clumped isotope(D47)and fluid inclusion analyses of carbonate minerals filled in pores and fractures,this study ascertained the fracturing timing of the Jurassic reservoirs in the Dibei-Tuziluoke Gas Field,Kuqa Foreland Basin.Data from outcrops and borehole images show two dominant fracture sets in the study area:W-E and NE-SW striking fractures.Some W-E striking fractures are carbonate-filled,while NE-SW striking fractures lack mineral fillings.Bitumen veins,not easy to be identified in borehole images,are prevalent in cores.The petrographic analysis reveals that these bitumen veins formed before the calcite cementation in pores and display high viscosity and low maturity.Homogenization temperatures(T_(h))from primary fluid inclusion assemblages in two representative calcite vein samples were notably lower than T△_(47) values from corresponding samples.This suggests the △_(47) signature underwent alteration due to partial reordering during burial.Thus,△_(47)-derived temperatures(apparent temperatures)may not faithfully represent the mineral precipitation temperatures.When plotting these apparent temperatures vs.the burial history,only the possible latest ages of fracturing emerged.These ages were further refined by considering petroleum charging,tectonic evolution,and stress orientation.Bitumen-filled fractures likely resulted from the Late Cretaceous uplift,marking the migration of low-maturity hydrocarbons in the study area.Carbonate-filled E-W striking fractures emerged during the late Miocene(~13e6.5 Ma)alongside fold development.NE-striking fractures that crosscut W-E ones possibly formed recently due to stress reorientation. 展开更多
关键词 Fracture Borehole imaging Bitumen vein Clumped isotope Fracturing timing
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Expression and significance of pigment epithelium-derived factor and vascular endothelial growth factor in colorectal adenoma and cancer
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作者 Ye Yang Wu Wen +6 位作者 Feng-Lin Chen Ying-Jie Zhang Xiao-Cong Liu Xiao-Yan Yang Shan-Shan Hu Ye Jiang jing yuan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期670-686,共17页
BACKGROUND The incidence and mortality of colorectal cancer(CRC)are among the highest in the world,and its occurrence and development are closely related to tumor neovascularization.When the balance between pigment ep... BACKGROUND The incidence and mortality of colorectal cancer(CRC)are among the highest in the world,and its occurrence and development are closely related to tumor neovascularization.When the balance between pigment epithelium-derived factors(PEDF)that inhibit angiogenesis and vascular endothelial growth factors(VEGF)that stimulate angiogenesis is broken,angiogenesis is out of control,resulting in tumor development.Therefore,it is very necessary to find more therapeutic targets for CRC for early intervention and later treatment.AIM To investigate the expression and significance of PEDF,VEGF,and CD31-stained microvessel density values(CD31-MVD)in normal colorectal mucosa,adenoma,and CRC.METHODS In this case-control study,we collected archived wax blocks of specimens from the Digestive Endoscopy Center and the General Surgery Department of Chengdu Second People's Hospital from April 2022 to October 2022.Fifty cases of specimen wax blocks were selected as normal intestinal mucosa confirmed by electronic colonoscopy and concurrent biopsy(normal control group),50 cases of specimen wax blocks were selected as colorectal adenoma confirmed by electronic colonoscopy and pathological biopsy(adenoma group),and 50 cases of specimen wax blocks were selected as CRC confirmed by postoperative pathological biopsy after inpatient operation of general surgery(CRC group).An immunohistochemical staining experiment was carried out to detect PEDF and VEGF expression in three groups of specimens,analyze their differences,study the relationship between the two and clinicopathological factors in CRC group,record CD31-MVD in the three groups,and analyze the correlation of PEDF,VEGF,and CD31-MVD in the colorectal adenoma group and the CRC group.The F test or adjusted F test is used to analyze measurement data statistically.Kruskal-Wallis rank sum test was used between groups for ranked data.The chi-square test,adjusted chi-square test,or Fisher's exact test were used to compare the rates between groups.All differences between groups were compared using the Bonferroni method for multiple comparisons.Spearman correlation analysis was used to test the correlation of the data.The test level(α)was 0.05,and a two-sided P<0.05 was considered statistically significant.RESULTS The positive expression rate and expression intensity of PEDF were gradually decreased in the normal control group,adenoma group,and CRC group(100%vs 78%vs 50%,χ^(2)=34.430,P<0.001;++~++vs+~++vs-~+,H=94.059,P<0.001),while VEGF increased gradually(0%vs 68%vs 96%,χ^(2)=98.35,P<0.001;-vs-~+vs++~+++,H=107.734,P<0.001).In the CRC group,the positive expression rate of PEDF decreased with the increase of differen-tiation degree,invasion depth,lymph node metastasis,distant metastasis,and TNM stage(χ^(2)=20.513,4.160,5.128,6.349,5.128,P<0.05);the high expression rate of VEGF was the opposite(χ^(2)=10.317,13.134,17.643,21.844,17.643,P<0.05).In the colorectal adenoma group,the expression intensity of PEDF correlated negatively with CD31-MVD(r=-0.601,P<0.001),whereas VEGF was not significantly different(r=0.258,P=0.07).In the CRC group,the expression intensity of PEDF correlated negatively with the expression intensity of CD31-MVD and VEGF(r=-0.297,P<0.05;r=-0.548,P<0.05),while VEGF expression intensity was positively related to CD31-MVD(r=0.421,P=0.002).CONCLUSION It is possible that PEDF can be used as a new treatment and prevention target for CRC by upregulating the expression of PEDF while inhibiting the expression of VEGF. 展开更多
关键词 Pigment epithelium-derived factors Vascular endothelial growth factor Microvessel density Colorectal adenoma Colorectal cancer Targeted therapy
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Detection of LAMA2 c.715C>G:p.R239G mutation in a newborn with raised creatine kinase: A case report
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作者 jing yuan Xiang-Ming Yan 《World Journal of Clinical Cases》 SCIE 2024年第14期2445-2450,共6页
BACKGROUND We report a rare case of primary clinical presentation featuring elevated creatine kinase(CK)levels in a neonate,which is associated with the LAMA2 gene.In this case,a heterozygous mutation in exon5 of the ... BACKGROUND We report a rare case of primary clinical presentation featuring elevated creatine kinase(CK)levels in a neonate,which is associated with the LAMA2 gene.In this case,a heterozygous mutation in exon5 of the LAMA2 gene,c.715C>G(resulting in a change of nucleotide number 715 in the coding region from cytosine to gua-nine),induced an amino acid alteration p.R239G(No.239)in the patient,repre-senting a missense mutation.This observation may be elucidated by the neonatal creatine monitoring mechanism,a phenomenon not previously reported.CASE SUMMARY We analysed the case of a neonate presenting solely with elevated CK levels who was eventually discharged after supportive treatment.The chief complaint was identification of increased CK levels for 15 d and higher CK values for 1 d.Ad-mission occurred at 18 d of age,and despite prolonged treatment with creatine and vitamin C,the elevated CK levels showed limited improvement.Whole exo-me sequencing revealed the presence of a c.715C>G mutation in LAMA2 in the newborn,correlating with a clinical phenotype.However,the available informa-tion offers insufficient evidence for clinical pathogenicity.CONCLUSION Mutations in LAMA2 are associated with the clinical phenotype of increased neonatal CK levels,for which no specific treatment exists.Whole genome sequen-cing facilitates early diagnosis. 展开更多
关键词 Creatine kinase LAMA2 Gene mutation NEONATE Case report
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建筑工人的日常生活信息搜寻行为研究
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作者 敬瑗 彭雪琴 全惠 《情报探索》 2024年第5期96-102,共7页
[目的/意义]针对建筑工人开展调查,了解该群体应用智能设备的日常生活信息搜寻行为,旨在供相关信息服务部门参考,以便改善信息服务,满足他们的日常生活信息需求。[方法/过程]基于SOR模型和日常生活信息搜寻行为理论构建建筑工人日常生... [目的/意义]针对建筑工人开展调查,了解该群体应用智能设备的日常生活信息搜寻行为,旨在供相关信息服务部门参考,以便改善信息服务,满足他们的日常生活信息需求。[方法/过程]基于SOR模型和日常生活信息搜寻行为理论构建建筑工人日常生活信息搜寻行为分析框架,以此为基础提出六大假设。[结果/结论]现阶段建筑工人日常生活信息搜寻行为处于中等水平;社会因素是建筑工人日常生活信息搜寻行为的重要环节,具有正向影响作用;个人心理因素起完全中介作用。 展开更多
关键词 SOR模型 信息搜寻行为 日常生活信息搜寻行为 建筑工人
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深度学习下的大学英语课程思政教学设计与实践研究
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作者 井媛 李梦洋 +1 位作者 张迎 于琦 《科教文汇》 2023年第20期125-127,共3页
大学英语课程应如何切实践行立德树人的教育使命,将价值塑造、知识传授和能力培养融为一体,为国家培养出具有家国情怀、国际视野和创新能力的人才,是一个值得深入研究的问题。目前对于大学英语课程思政建设的研究多从较宏观的层面对课... 大学英语课程应如何切实践行立德树人的教育使命,将价值塑造、知识传授和能力培养融为一体,为国家培养出具有家国情怀、国际视野和创新能力的人才,是一个值得深入研究的问题。目前对于大学英语课程思政建设的研究多从较宏观的层面对课程思政的内涵、意义等方面进行探讨,而从课程思政教学设计与实践角度进行的研究还有待进一步充实。该文基于深入学习的内涵与特征,以学习者为中心,结合学习者的产出需求,从理解、思辨、实践三个层次进行大学英语课程思政教学设计与实践,提升大学英语课程思政教学的有效性。 展开更多
关键词 大学英语 课程思政 深度学习 教学设计
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基于流模型的低照度超分辨率重建
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作者 景源 朱道强 《辽宁大学学报(自然科学版)》 CAS 2023年第3期239-247,共9页
将低照度低分辨率图像增强到正常曝光高分辨率图像具有高度的不确定性,即它们之间的映射关系是一对多的.以往基于像素重建图像和确定图像的过程未能捕捉正常曝光图像的复杂条件分布,导致不适当的亮度、残余噪声和伪影.在本文中,通过一... 将低照度低分辨率图像增强到正常曝光高分辨率图像具有高度的不确定性,即它们之间的映射关系是一对多的.以往基于像素重建图像和确定图像的过程未能捕捉正常曝光图像的复杂条件分布,导致不适当的亮度、残余噪声和伪影.在本文中,通过一个已经提出的标准化流模型来构建这种一对多的关系.一种以低照度图像的特征为条件,学习将正常曝光图像的分布映射为高斯分布的可逆网络模型,这样可以很好地模拟正常曝光图像的条件分布.可逆网络模型的另一个优点是在训练过程中被一个描述正常图像流形结构的损失函数约束.在LOL(Low-light)数据集上的实验结果表明,该方法相比较其他方法,获得了更高峰值信噪比(PSNR),更高结构相似度(SSIM),更少学习感知图像块相似度(LPIPS). 展开更多
关键词 低照度图像增强 超分辨率重建 流模型
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新时代背景下基于专业导向培养的大学英语教学研究 被引量:1
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作者 李梦洋 井媛 +1 位作者 马永良 刘睿 《湖北开放职业学院学报》 2023年第3期180-181,184,共3页
新时代现代教育行业的蓬勃发展,大学英语教育也面临着转型,这就要求高校英语教师改变封闭保守的教育理念,赋予英语全新的教育内容和内涵,彰显出英语教学的新价值。然而,大学英语教学与专业课程内容的关联性不大,很少基于专业导向对授课... 新时代现代教育行业的蓬勃发展,大学英语教育也面临着转型,这就要求高校英语教师改变封闭保守的教育理念,赋予英语全新的教育内容和内涵,彰显出英语教学的新价值。然而,大学英语教学与专业课程内容的关联性不大,很少基于专业导向对授课内容进行筛选,使得大学英语教学的工具性价值下降,出现了“抬头率”不高,课堂学习氛围日渐低迷等问题。于此,需要以专业为导向对现有的大学英语教学模式进行改革,通过转变固化观念、分析不同专业的特点,积极寻找大学英语与专业课程之间的契合点,从而扎实推动大学英语教学与专业课程的交叉融合。 展开更多
关键词 新时代 专业导向培养 大学英语教学
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阔叶红松林中花鼠的食物组成及取食偏好 被引量:1
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作者 魏爽 梁振玲 +3 位作者 滕威 荆媛 于美辰 戎可 《野生动物学报》 北大核心 2023年第3期506-514,共9页
为调查阔叶红松(Pinus koraiensis)林中花鼠(Tamias sibiricus)的食物组成、取食偏好及营养对食物选择的影响,以黑龙江省凉水国家级自然保护区内野生花鼠为研究对象,采用野外直接观察法、实验室笼养法结合营养测定的方式对不同季节花鼠... 为调查阔叶红松(Pinus koraiensis)林中花鼠(Tamias sibiricus)的食物组成、取食偏好及营养对食物选择的影响,以黑龙江省凉水国家级自然保护区内野生花鼠为研究对象,采用野外直接观察法、实验室笼养法结合营养测定的方式对不同季节花鼠的食物组成和取食偏好进行调查。野外调查结果表明:花鼠是以植食为主的啮齿动物,不同季节植物性食物占其食物组成的95%以上,其余5%的食物为蜗牛、蚯蚓等动物性食物;春、夏季花鼠取食植物的种类存在差异,春季花鼠取食频次最高的是延胡索(Corydalis yanhusuo),夏季为透茎冷水花(Pilea pumila),秋季为红松种子。实验室笼养测得的结果与野外调查结果相符,结合营养测定结果显示花鼠偏好取食粗脂肪、能量含量高和纤维素含量低的食物,而粗蛋白含量与花鼠的取食量之间没有明显相关。 展开更多
关键词 花鼠 食性 营养 阔叶红松林
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