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移动互联网的大规模学习服务生态环境研究

电化教育研究 2019年第4期40卷 53-58页

作者：方海光刘嘉琪魏文雅汪时冲首都师范大学教育学院北京100048 首都师范大学教师教育学院北京100048

不同于传统教育模式和新兴的互联网教育模式,基于移动互联网的大规模学习服务生态环境将伴随5G网络和终端产业发展成为下一代学习服务新模式。其中,如何实现学生、教师以及家长之间随时随地的学习服务和精准服务的闭环环境成为研究的关... 详细信息

不同于传统教育模式和新兴的互联网教育模式,基于移动互联网的大规模学习服务生态环境将伴随5G网络和终端产业发展成为下一代学习服务新模式。其中,如何实现学生、教师以及家长之间随时随地的学习服务和精准服务的闭环环境成为研究的关键所在。研究以教育主体和教育环境为核心,结合移动互联网的构成要素创建基于移动互联网的大规模学习服务生态环境模型(Mass Learning Service Ecological Model Based On Mobile Internet,简称3M模型),从学习空间、学习媒体、学习资源、学习支持和学习平台支持五个方面特征对其下一代学习服务生态环境进行了阐述,并分析了基于3M模型的五个典型智能学习场景:无人智能化学习环境、物联协同学习环境、智能终端学习环境、多维度空间学习环境、智能教学机器人,并构建基于学习场景划分的智能学习中心服务算法ILCSA,最后以基于移动互联网的中小学大规模学习移动终端应用案例作为验证。

关键词：移动互联网教育移动终端教育大数据学习服务生态环境

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点在不同性质基下轨道稠密的一个注记

江汉大学学报（自然科学版） 2018年第4期46卷 310-313页

作者：王文娅危合文江汉大学数学与计算机科学学院湖北武汉430056

构造了一个集合,此集合中的点关于b-进制展式以及连分数展式都是稠密的。更具体的说,证明了存在一个非正规数的集合使得下列数公式成立。dim_H——————{f^nx(mod 1):n≥1}+dim_H——————{T^nx(mod 1):n≥1}>1。

关键词： Hausdorff维数 b-进制展式连分数展式稠密

滇杨幼苗对镉、锌胁迫的生理响应与耐受性研究

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西南林业大学学报（自然科学） 2024年第1期44卷 31-39页

作者：王艳霞郑武扬侯磊刘楚天何承忠陈柱学魏文雅西南林业大学生态与环境学院云南昆明650233 西南林业大学云南省山地农村生态环境演变与污染治理重点实验室云南昆明650233 西南林业大学生命科学学院云南昆明650233

为探究滇杨幼苗在Cd、Zn单一及复合胁迫下的生长、生理响应与耐受特征,采用土培盆栽的方式开展研究。结果表明:Cd、Zn单一及复合胁迫未显著改变滇杨株高、地径和总生物量,但单一Zn胁迫显著提高总根长、根表面积和根体积,Cd-Zn胁迫显著... 详细信息

为探究滇杨幼苗在Cd、Zn单一及复合胁迫下的生长、生理响应与耐受特征,采用土培盆栽的方式开展研究。结果表明:Cd、Zn单一及复合胁迫未显著改变滇杨株高、地径和总生物量,但单一Zn胁迫显著提高总根长、根表面积和根体积,Cd-Zn胁迫显著降低总根长;Zn可改善滇杨的苗木生长质量,Cd可导致滇杨生长变差,而Cd-Zn复合胁迫时生长状况最差。Cd、Zn单一胁迫未显著改变滇杨叶片的光合色素含量和净光合速率,Cd-Zn复合胁迫时叶绿素含量显著降低,但净光合速率和光响应特征参数变化不显著,而Cd单一胁迫时滇杨的R_(d)和LCP较CK显著增高,Zn单一胁迫时则LSP显著增高。Cd和Cd-Zn胁迫可激发滇杨氧化应激防御系统,使SOD和CAT活性显著提高,MDA和TPh含量无显著变化,Zn胁迫时SOD、CAT、MDA和TPh含量均无显著变化。滇杨幼苗对Cd、Zn单一及复合胁迫表现出耐受性,可作为Cd、Zn污染土壤生态修复的重要候选树种,其综合耐受值为Zn>CK>Cd>Cd-Zn。

关键词：滇杨镉、锌胁迫生长光合生理重金属

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针刺联合神经干细胞修复脊髓损伤的科学依据

中国组织工程研究 2025年第19期29卷 4111-4121页

作者：黄晓萌张芝兰尚文雅黄靖韦慧麟李冰任亚锋河南中医药大学康复医学院河南省郑州市450046 河南中医药大学第一附属医院河南省郑州市450000

背景:脊髓损伤是由创伤性或非创伤性事件引起的一种神经系统疾病,常导致损伤节段以下严重功能障碍。近年来,神经干细胞移植被认为在调控脊髓损伤后的炎症反应、抑制胶质瘢痕的过度增生以及促进神经再生方面具有显著的治疗潜力。目的:综... 详细信息

背景:脊髓损伤是由创伤性或非创伤性事件引起的一种神经系统疾病,常导致损伤节段以下严重功能障碍。近年来,神经干细胞移植被认为在调控脊髓损伤后的炎症反应、抑制胶质瘢痕的过度增生以及促进神经再生方面具有显著的治疗潜力。目的:综述并讨论针刺及神经干细胞移植疗法在抑制脊髓损伤诱导的继发性损伤中的潜在作用机制,深入探讨其治疗脊髓损伤的科学依据。方法:以“脊髓损伤,针刺,神经干细胞,SDF-1α/CXCR4轴”为中文检索词,以“Spinal cord injury,acupuncture,neural stem cells,SDF-1α/CXCR4 axis”为英文检索词,分别检索PubMed、Elsevier、万方及中国知网数据库,最终纳入96篇文献,汇总分析了针刺联合神经干细胞治疗脊髓损伤的相关研究成果,总结了这一联合疗法在治疗脊髓损伤后继发性损伤中的相关机制。结果与结论:①基质细胞衍生因子1α(stromal-derived factor 1α,SDF-1α)/CXC趋化因子受体4(chemokine receptor 4,CXCR4)轴在神经干细胞移植治疗脊髓损伤中扮演着至关重要的角色,该信号传导机制不仅影响神经干细胞的迁移、增殖和分化,更是决定干细胞归巢至损伤部位效率的关键因素。因此,针对该轴线的调控,对于提升脊髓损伤的治疗效果具有重要意义。②针刺作为一种传统中医疗法,在脊髓损伤的继发性损伤调控中展现出独特的优势,它能够通过调节炎症反应、抑制细胞凋亡、改善微循环、减少神经胶质瘢痕形成以及对抗氧化应激等多种途径,有效减轻脊髓损伤后的继发性损伤。③针刺还能够影响SDF-1α/CXCR4轴的表达与功能,从而增强神经干细胞的归巢和存活能力,促进神经再生和功能恢复。④结合针刺与干细胞移植的疗法,是一种创新且较好的脊髓损伤治疗策略,适用于修复神经环路,它结合了传统中医的智慧与现代生物技术的优势,为脊髓损伤患者提供了新的治疗选择。然而,目前这种联合疗法仍处于研究和探索阶段,其长期疗效和安全性尚需进一步验证。⑤综合而言,针刺及神经干细胞移植治疗脊髓损伤具有巨大的临床应用潜力,但仍需深入研究和优化治疗方案。未来,期待通过更多的临床试验和机制研究,进一步揭示这一疗法的疗效机制和最佳适应证,为脊髓损伤患者带来更好的康复希望和更高效的治疗效果。

关键词：针刺神经干细胞脊髓损伤继发性损伤神经再生炎症反应氧化应激神经保护基质细胞衍生因子1α(SDF-1α)/CXC趋化因子受体4(CXCR4)轴协同机制

Refill Friction Stir Spot Welding Al Alloy to Copper via Pure Metallurgical Joining Mechanism

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 90-97页

作者： Zhikang Shen Yuquan Ding wei Guo Wentao Hou Xiaochao Liu Haiyan Chen Fenjun Liu wenya Li Adrian Gerlich School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China Centre for Advance Materials Joining University of WaterlooWaterloo N2L 3G1Canada College of Energy Engineering Yulin UniversityYulin 719000China

The current investigation of refill friction stir spot welding(refill FSSW)Al alloy to copper primarily involved plunging the tool into bottom copper sheet to achieve both metallurgical and mechanical interfacial *** to conventional FSSW and pinless FSSW,weld strength can be significantly improved by using this ***,tool wear is a critical issue during refill *** this study,defect-free Al/copper dissimilar welds were successfully fabricated using refill FSSW by only plunging the tool into top Al alloy ***,two types of continuous and ultra-thin intermetallic compounds(IMCs)layers were identified at the whole Al/copper ***,strong evidence of melting and resolidification was observed in the localized *** peak temperature obtained at the center of Al/copper interface was 591℃,and the heating rate reached up to 916℃/s during the sleeve penetration phase.A softened weld region was produced via refill FSSW process,the hardness profile exhibited a W-shaped appearance along middle thickness of top Al *** weld lap shear load was insensitive to the welding condition,whose scatter was rather *** fracture path exclusively propagated along the IMCs layer of Cu_(9)Al_(4) under the external lap shear loadings,both CuAl_(2) and Cu_(9)Al_(4) were detected on the fractured surface on the copper *** research indicated that acceptable weld strength can be achieved via pure metallurgical joining mechanism,which has significant potential for the industrial applications.

关键词： Refill friction stir spot welding Al alloy Copper Interfacial microstructure Mechanical properties

家庭认知环境对儿童早期语言发育的影响:一项上海市的回顾性病例对照研究

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中国全科医学 2025年第1期28卷 53-58页

作者：郭志超崔丹包嘉珺施渭青韦康杨兴堂俞文雅上海市宝山区月浦镇社区卫生服务中心预防保健科 200941 上海交通大学医学院公共卫生学院上海市200025

背景儿童早期语言发育迟缓发生率高、早期识别率低,对儿童其他维度的早期发展有显著负面影响。家庭认知环境是影响儿童早期语言发育的关键因素。目的本研究旨在探索家庭认知环境对儿童早期语言发育的影响,从家庭认知环境的社区干预角度... 详细信息

背景儿童早期语言发育迟缓发生率高、早期识别率低,对儿童其他维度的早期发展有显著负面影响。家庭认知环境是影响儿童早期语言发育的关键因素。目的本研究旨在探索家庭认知环境对儿童早期语言发育的影响,从家庭认知环境的社区干预角度,为儿童早期的语言发育促进提供理论证据。方法采用回顾性病例对照研究,对2018—2020年在上海市某社区卫生服务中心儿童保健门诊体检的4307名儿童在1、2、3周岁时采用上海市小儿发育筛查量表Ⅱ(DenveRⅡ)进行发育筛查,将筛查出的语言发育迟缓的172名儿童作为观察组,以年龄作为配对因素,按照1∶3的比例纳入516名语言发育正常的儿童作为对照组。收集两组儿童出生基本特征、父母人口学特征、母亲孕期和分娩特征以及家庭认知环境特征信息。采用Logistic回归分析探讨儿童早期语言发育迟缓的影响因素。结果早期语言发育迟缓的儿童共172名,发生率为3.99%,其中,1岁儿童57名(33.14%),2岁儿童92名(53.49%),3岁儿童23名(13.37%)。病例组儿童男性、早产、母亲文化程度为高中以下比例高于对照组(P<0.05)。病例组儿童的总体家庭认知环境及情感温暖、社会适应、语言环境和忽视环境弱于对照组(P<0.05)。儿童早产、母亲文化程度低(高中以下)、家庭认知环境不良是儿童早期语言发育迟缓的危险因素(P<0.05)。结论在2岁前进行语言发育干预是有效降低儿童语言发育迟缓率的关键。社区儿童保健医生指导优化家庭养育环境、协助建立良好亲子沟通和交流互动,是促进儿童早期语言发育的有效策略,尤其要关注出生胎龄小和母亲文化程度低的家庭,为其提供更有针对性的亲子活动和亲子沟通方面的干预和指导。

关键词：语言发展障碍家庭环境认知环境儿童儿童语言儿童早期发展病例对照研究

Toll-like receptor 4 plays an anti-HBV role in a murine model of acute hepatitis B virus expression

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World Journal of Gastroenterology 2005年第42期11卷 6631-6637页

作者： Wen-wei Chang Ih-Jen Su Ming-Derg Lai Wen-Tsan Chang wenya Huang Huan-Yao Lei Institute of Basic Medical Science NationalCheng Kung University Medicine College Tainan Taiwan China Division of Clinical Research National HealthResearch Institute Tainan Taiwan China Department of Biochemistry National Cheng Kung University Medicine College TainanTaiwan China Department of Medical Laboratory Scienceand Biotechnology National Cheng Kung University MedicineCollege Tainan Taiwan China Department of Microbiology and Immunology National Cheng Kung University Medicine College TainanTaiwan China

AIM： Toll-like receptor 4 （TLR4） has been shown to be important for bacterial infection, especially to lipopolysaccharide signaling. Its possible role in HBV infection is studied in the present study. MATERIALS AND METHODS： pHBV3.6 plasmid, containing full-length HBV genome was used in the murine model of acute HBV expression by hydrodynamics in vivo transfection. TLR4 normal or mutant mouse strain was compared to investigate the possible role of TLR4 in acute HBV expression. RESULTS： After pHBV3.6 injection, the infiltrating leukocytes expressed TLR4 were observed nearby the HBsAg-expressing hepatocytes. The HBV antigenemia as well as the replication and transcription were higher in TLR4-mutant C3H/HeJ mice than in normal C3H/ HeN mice. The HBV-specific immune responses were impaired in the liver or spleen of the C3H/HeJ mice. Their inducible nitric oxide synthase （iNOS） expression on the hepatic infiltrating cells was also impaired. When adoptively transferring splenocytes from C3H/HeN mice to C3H/HeJ mice, the HBV replication was inhibited to the level as that of C3H/HeN. CONCLUSION： These results suggest that TLR4 plays an anti-HBV role in vivo through the induction of iNOSexpression and HBV-specific immune responses after HBV expression.

关键词： TLR4 Rodent HBV iNOS Liver

Geological characteristics and key exploration technologies of continental shale oil sweet spots: A case study of Member 2 of Kongdian Formation in the Cangdong sag in the Huanghua depression, Bohai Bay Basin

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Petroleum Research 2019年第2期4卷 97-112页

作者： Xianzheng Zhao Xiugang Pu Fengming Jin Wenzhong Han Zhannan Shi Aibing Cai Aiguo Wang Quansheng Guan wenya Jiang wei Zhang PetrolChina Dagang Oilfield Company Tianjin300280China

Under the general trend of stepping-up oil and gas exploration and development in China,the unconventional oil and gas resources such as shale oil and gas have become an important *** continental shale oil resources are developed in Member 2 of Kongdian Formation(Ek2)of the Cangdong sag in the Huanghua depression of the Bohai Bay Basin which has complex structure,strong heterogeneity,and large buried depth,thus,the geological characteristic of shale oil accumulation and key exploration technologies are investigated on base of the system coring of 635.8 m,centimeter-level fine description and analysis of over ten thousand samples,therefore,the“four accurate”technologies have been developed,including the accurate selection of sweet spot areas,accurate drilling of sweet spot layers,accurate fracturing of sweet spot layers and accurate measure of fracture-rich *** results show that the continental shale strata in Member 2 of Kongdian Formation can be divided into three types:felsic shale,limy dolomitic shale and mixed *** Member 2 of Kongdian Formation is characterized by diverse mineral components,abundant laminae,good source rocks and medium thermal evolution degree,tight reservoir with rich micropore and microfractures,high oil saturation and brittle mineral content,indicating good prospect of shale oil *** sedimentological study,TOC and Ro evaluation,brittle mineral calculation,and seismic fusion inversion,a total of 126 km^(2) of Class I sweet spots in Member 2 of Kongdian Formation was delineated comprehensively,which guides horizontal well deployment(Well GD1701H and Well GD1702H).The drilling rate of sweet spot of these two horizontal wells is up to 96%by tracing thin layer through fine calibration,locating compartment through fine inversion,ensuring window entry through precise positioning,and tracking sweet spot through *** “one-excellent and five-highs”criterion is used to select perforation points to

关键词： Shale oil Sweet spot evaluation Fracturing intervals and perforation clusters Member 2 of Kongdian formation Cangdong sag Bohai Bay Basin

Reservoirs properties of slump-type sub-lacustrine fans and their main control factors in first member of Paleogene Shahejie Formation in Binhai area, Bohai Bay Basin, China

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Petroleum Exploration and Development 2020年第5期47卷 977-989页

作者： PU Xiugang ZHAO Xianzheng WANG Jiahao WU Jiapeng HAN Wenzhong WANG Hua SHI Zhannan JIANG wenya ZHANG wei Dagang Oilfield Company PetroChinaTianjin 300280China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of GeosciencesWuhan 430074China

High-yielding oil wells were recently found in the first member of Paleogene Shahejie Formation,the Binhai area of Qikou Sag,providing an example of medium-and deep-buried high-quality reservoirs in the central part of a faulted lacustrine *** using data of cores,cast thin sections,scanning electron microscope and physical property tests,the sedimentary facies,physical properties and main control factors of the high-quality reservoirs were *** reservoirs are identified as deposits of slump-type sub-lacustrine fans,which are marked by muddy fragments,slump deformation structure and Bouma sequences in *** present mostly medium porosity and low permeability,and slightly medium porosity and high *** have primary intergranular pores,intergranular and intragranular dissolution pores in feldspar and detritus grains,and structural microcracks as storage *** main factors controlling the high quality reservoirs are as follows:(1)Favorable sedimentary microfacies of main and proximal distributary gravity flow *** microfacies with coarse sediment were dominated by transportation and deposition of sandy debris flow,and the effect of deposition on reservoir properties decreases with the increase of depth.(2)Medium texture *** is shown by medium-sorted sandstones that were formed by beach bar sediment collapsing and redepositing,and was good for the formation of the primary intergranular pores.(3)High content of intermediate-acid volcanic rock *** reservoir sandstone has high content of detritus of various components,especially intermediate-acid volcanic rock detritus,which is good for the formation of dissolution pores.(4)Organic acid *** was attributed to hydrocarbon maturity during mesodiagenetic A substage.(5)Early-forming and long lasting overpressure.A large-scale overpressure compartment was caused by under-compaction and hydrocarbon generation pressurization related to thick deep-lacustrine mu

关键词： faulted lacustrine basin slump-type sub-lacustrine fan reservoir Paleogene Shahejie Formation porosity-permeability structure Qikou Sag Bohai Bay Basin

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