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“以学生为中心”视角下高职院校课程的改革与实践——以“植物组织培养技术”课程为例

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北京农业职业学院学报 2024年第1期38卷 70-77页

作者：肖海峻张晋马静媛孟利前北京农业职业学院北京102442

高职院校肩负着培养高技能型人才的重任,以立德树人为根本任务,不断深化产教融合,推进职业教育高质量发展。“以学生为中心”的教学理念是推进职业教育高质量发展的具体体现。围绕“以学生为中心”这个主题,从课程思政、教学内容、教学... 详细信息

高职院校肩负着培养高技能型人才的重任,以立德树人为根本任务,不断深化产教融合,推进职业教育高质量发展。“以学生为中心”的教学理念是推进职业教育高质量发展的具体体现。围绕“以学生为中心”这个主题,从课程思政、教学内容、教学设计与组织、教学评价等方面进行改革与探索,实现教学过程工作化,知识、能力、素质培养同步化,教学效果显著。

关键词：以学生为中心植物组织培养技术课程改革

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黄河三角洲湿地发展概述及治理修复建议

海洋开发与管理 2024年第2期41卷 110-114页

作者：尹聪兰丽茜宋晓晓陈默严晋山东省海洋生态环境与防灾减灾重点实验室青岛266061 自然资源部北海海洋技术中心青岛266102

黄河流域在我国经济社会发展和生态安全方面具有十分重要的地位,其下游的黄河三角洲分布有世界上暖温带保存最广阔、最完善、最年轻的滨海湿地生态系统,该区域特殊的地质地貌决定了其生态多样性,需要进行重点研究和保护。文章立足于我... 详细信息

黄河流域在我国经济社会发展和生态安全方面具有十分重要的地位,其下游的黄河三角洲分布有世界上暖温带保存最广阔、最完善、最年轻的滨海湿地生态系统,该区域特殊的地质地貌决定了其生态多样性,需要进行重点研究和保护。文章立足于我国现有湿地保护政策和湿地面积缩小的现状,提出黄河三角洲湿地保护可着重围绕其岸线变化、冲淤速率、地形地貌等开展研究,并采用减压分洪扩充法等治理修复方法扩大湿地面积,为推动黄河流域及黄河三角洲湿地的生态保护和高质量发展提供有效参考。

关键词：湿地黄河三角洲湿地退化湿地研究治理修复

Simultaneous detection and characterization of toxigenic Clostridium difficile directly from clinical stool specimens

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Frontiers of Medicine 2018年第2期12卷 196-205页

作者： Hanjiang Lai Chen Huang Jian Cai Julian Ye Jun She Yi Zheng liqian.Wang Yelin Wei Weijia Fang Xianjun Wang Yi-Wei Tang Yun Luo Dazhi jin The First People's Hospital of Xiaoshan District Hangzhou 311021 China Department of Microbiology Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051 China Department of Disease Control and Prevention Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051 China Biotherapy Center for Medical Oncology the First Affiliated Hospital Zhejiang University Hangzhou 310003 China Department of Laboratory Medicine HangzhouFirst People's Hospital Hangzhou 310006 China Department of Laboratory Medicine Memorial Sloan Kettering Cancer Center Department of Pathology and Laboratory Medicine Weill Medical College of Cornell University New York NY 10065 USA

We employed a multiplex polymerase chain reaction （PCR） coupled with capillary electrophoresis （mPCR-CE） targeting six Clostridium difficile genes, including tPi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for simultaneous detection and characterization of toxigenic C. difficile directly from fecal specimens. The mPCR-CE had a limit of detection of 10 colony-forming units per reaction with no cross-reactions with other related bacterial genes. Clinical validation was performed on 354 consecutively collected stool specimens from patients with suspected C. difficile infection and 45 isolates. The results were compared with a reference standard combined with BD MAX Cdiff, real-time cell analysis assay （RTCA）, and mPCR-CE. The toxigenic C. difficile species were detected in 36 isolates and 45 stool specimens by the mPCR-CE, which provided a positive rate of 20.3% （81/399）. The mPCR-CE had a specificity of 97,2% and a sensitivity of 96.0%, which was higher than RTCA （χ^2 = 5.67, P = 0.017） but lower than BD MAX Cdiff （P = 0.245）. Among the 45 strains, 44 （97.8%） were determined as non- ribotype 027 by the mPCR-CE, which was fully agreed with PCR ribotyping. Even though ribotypes 017 （n = 8, 17.8%）, 001 （n = 6, 13.3%）, and 012 （n = 7, 15.6%） were predominant in this region, ribotype 027 was an important genotype monitored routinely. The mPCR-CE provided an alternative diagnosis tool for the simultaneous detection of toxigenic C. difficile in stool and potentially differentiated between RT027 and non-RT027.

关键词： Clostridium difficile multiplex PCR capillary electrophoresis detection characterization

Pseudorange Bias Correction for BDSBAS Single Frequency Service

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Pseudorange Bias Correction for BDSBAS Single Frequency Serv...

Spirulina platensis aqueous extracts ameliorate colonic mucosal damage and modulate gut microbiota disorder in mice with ulcerative colitis by inhibiting inflammation and oxidative stress

第十三届中国卫星导航年会

作者： liqian.Zhao Biao jin.Qijia Dong Zixiao Li Ningning Liu Space Star Technology Co. Ltd.

BDSBAS broadcasts SBAS corrections and integrity information via BDSBAS-B1 C signals of BeiDou-3 GEO satellites to improve the accuracy and integrity for GPS L1 CA single-frequency users in BDSBAS service area. However, if the GPS receiver type and technical status of BDSBAS reference station is quite different from the receiver of GPS ground operational control system and the BDSBAS receivers do not fully refer to the receivers of GPS ground operational control system to adjust the correlator spacing and front-end bandwidth, there will be inevitable relative pseudorange bias between the BDSBAS receivers and GPS ground operational control system receivers. Pseudorange bias is an important factor restricting the performance of BDSBAS singlefrequency service. This contribution analyzes the impact of GPS satellite pseudorange bias on the accuracy of BDSBAS single-frequency service, and then proposes a pseudorange bias correction method based on the Timing Group Delay（TGD） parameters, which can eliminate the impact of pseudorange bias on the GPS L1 CA SBAS positioning accuracy and improve the single-frequency service performance of BDSBAS. Six stations in the BDSBAS service area are used to carry out GPS L1 CA SBAS positioning experiment, the experiment results reveal that the average 95% positioning accuracy has a significant improvement after using the mentioned method to correct the pseudorange bias. The positioning errors are reduced from 1.70 m to 1.38 m and from 2.83 m to 2.29 m in the horizontal and vertical directions, respectively.

关键词： BDSBAS Reference Station Pseudorange Bias Timing Group Delay Service Performance

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2022年第6期23卷 481-501页

作者： Jian WANG liqian.SU Lun ZHANG Jiali ZENG Qingru CHEN Rui DENG Ziyan WANG Weidong KUANG Xiaobao jin.Shuiqing GUI Yinghua XU Xuemei LU Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances School of Life Science and BiopharmaceuticsGuangdong Pharmaceutical UniversityGuangzhou 510006China School of Pharmacy Guangdong Pharmaceutical UniversityGuangzhou 510006China Intensive Care Unit Shenzhen Second People’s Hospitalthe First Affiliated Hospital of Shenzhen UniversityShenzhen 518031China Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products National Institutes for Food and Drug ControlBeijing 102629China

Ulcerative colitis(UC)is a chronic and recurrent inflammatory bowel disease(IBD)that has become a major gastroenterologic problem during recent *** complicating factors are involved in UC development such as oxidative stress,inflammation,and microbiota *** factors exacerbate damage to the intestinal mucosal *** platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage ***,there have been few studies on the treatment of UC using *** aqueous extracts(SP),and the underlying mechanism of action of SP against UC has not yet been ***,we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal *** sulfate sodium(DSS)was used to establish a normal human colonic epithelial cell(NCM460)injury model and UC animal *** mitochondrial membrane potential assay 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and staining with Annexin V-fluorescein isothiocyanate(FITC)/propidium iodide(PI)and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury ***,hematoxylin and eosin(H&E)staining,transmission electron microscopy(TEM),enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qPCR),western blot,and 16S ribosomal DNA(rDNA)sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 *** vitro studies showed that SP alleviated DSS-induced NCM460 cell *** also significantly reduced the excessive generation of intracellular reactive oxygen species(ROS)and prevented mitochondrial membrane potential reduction after DSS *** vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the cont

关键词： Spirulina platensis aqueous extracts Ulcerative colitis Oxidative stress Inflammation Antioxidant Gut microbiota

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SBAS电文时序动态编排算法

北京航空航天大学学报 2021年第10期47卷 1996-2005页

作者：陈姗姗金彪赵立谦夏川茹王雷雷航天恒星科技有限公司北京100094 中国科学院上海天文台上海200030 天津航天中为数据系统科技有限公司天津300450

星基增强系统(SBAS)通过GEO卫星转发SBAS电文实现对GNSS服务性能的提升,以满足民航用户不同飞行阶段的导航需求,因此,合理有效的电文内容及播发时序设计是系统实现高质量服务的重要保证。为提高电文编排的灵活性,避免固定时序填补空余... 详细信息

星基增强系统(SBAS)通过GEO卫星转发SBAS电文实现对GNSS服务性能的提升,以满足民航用户不同飞行阶段的导航需求,因此,合理有效的电文内容及播发时序设计是系统实现高质量服务的重要保证。为提高电文编排的灵活性,避免固定时序填补空余电文引起的播发资源浪费,提出了一种SBAS电文时序动态编排算法,在满足国际标准要求的前提下,综合利用SBAS电文龄期和最大播发间隔实现待播发电文的自动选择。利用NTMF实测数据对当前各主要SBAS的电文进行了特性分析,对所提方法的单双频SBAS电文编排效果进行了评估。结果表明:所提算法可保证电文时序符合国际标准要求,实现了重要电文的优先播发,将空余时隙进行动态分配实现了各类型电文播发间隔的近等比例缩短。与固定时序相比,单频SBAS完好性电文播发间隔缩短约15.0%,首次定位时间缩短约8%,双频SBAS电文首次定位时间缩短约6.5%;与固定时序的BDSBAS B1C电文相比,完好性服务能力提升约14.7%,首次定位时间缩短约16.7%。所提算法有效提升了SBAS电文播发的播发效率,实现了SBAS播发资源的100%有效利用。

关键词：星基增强系统(SBAS) SBAS电文电文时序动态时序固定时序

气袋采样/热脱附-气相色谱-质谱法检测儿童地垫中35种挥发性有机物

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分析试验室 2020年第6期39卷 700-705页

作者：崔进刘成鑫陈姗崔立迁天津市产品质量监督检测技术研究院天津300384 天津大学天津300350

建立了热脱附-气相色谱-质谱法(TD-GC-MS)分析儿童地垫中35种挥发性有机物(VOCS)的检测方法。将样品裁剪后密封于Tedlar气体采样袋中,充入5 L N2,置于60℃的恒温烘箱中保持2h,冷至室温,用采样器抽取1 L气体经吸附管进行富集,用热脱附-... 详细信息

建立了热脱附-气相色谱-质谱法(TD-GC-MS)分析儿童地垫中35种挥发性有机物(VOCS)的检测方法。将样品裁剪后密封于Tedlar气体采样袋中,充入5 L N2,置于60℃的恒温烘箱中保持2h,冷至室温,用采样器抽取1 L气体经吸附管进行富集,用热脱附-气相色谱-质谱联用仪进行分析。考察了吸附填料的富集效果以及样品的处理温度、处理时间对测定结果的影响。35种VOCS在5~100 ng线性范围内,线性相关系数均达到0. 9934以上,检出限为0. 2~2. 3μg/m3。吸附管加标量为5,20,100 ng时,平均加标回收率为86. 0%~113. 8%,相对标准偏差(RSD,n=6)为0. 3%~11. 1%。结果表明,该方法适用于儿童地垫中VOCS的检测。

关键词：气袋采样热脱附-气相色谱-质谱法挥发性有机物儿童地垫

Zr35Ti30Cu8.25Be26.75非晶合金在高速率下的高温流变本构模型

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材料科学与工艺 2020年第6期28卷 1-7页

作者：邓磊姚丽倩周芃金俊松龚攀王新云材料成形与模具技术国家重点实验室(华中科技大学) 武汉430074

为研究锆基非晶合金在过冷液相区内较高温度区间和较高应变速率变形条件下的流变行为,准确描述温度和应变速率对非晶合金流变应力的影响,用Zwick/Roell力学性能实验机对Zr35Ti30Cu8.25Be26.75非晶合金进行高温(~1.2Tg)较高速(~100/s)下... 详细信息

为研究锆基非晶合金在过冷液相区内较高温度区间和较高应变速率变形条件下的流变行为,准确描述温度和应变速率对非晶合金流变应力的影响,用Zwick/Roell力学性能实验机对Zr35Ti30Cu8.25Be26.75非晶合金进行高温(~1.2Tg)较高速(~100/s)下的压缩实验,分别采用虚应力模型和提出的Maxwell-Pulse本构模型进行了应力、应变关系的表征。结果表明:Zr35Ti30Cu8.25Be26.75非晶合金的流变行为具有较强的温度和应变速率敏感性,即随着温度的降低和应变速率的升高,非晶合金的流变应力单调增加,同时其变形行为由平衡态牛顿流变转变为非平衡态的非牛顿流变;对比实验数据和模型预测数据发现,虚应力模型拟合结果偏差较大,误差大于50%,而Maxwell-Pulse本构模型预测值与实验值一致性好,准确率在90%以上,说明Maxwell-Pulse本构模型不仅能够同时描述Zr35Ti30Cu8.25Be26.75非晶合金的牛顿流变和非牛顿流变现象,也能够准确地反映Zr35Ti30Cu8.25Be26.75非晶合金在高温和较高应变速率变形条件下的应力应变关系。

关键词：非晶合金过冷液相区高应变速率流变行为本构模型

FC-AE-1553网络的“并发交换式”动态带宽调度机制

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北京航空航天大学学报 2016年第12期42卷 2579-2586页

作者：吴少俊赵光恒王立芊展月英王进王洪祥中国科学院空间应用工程与技术中心北京100094 中国科学院大学北京100049 北京邮电大学信息光子学与光通信国家重点实验室北京100876

为提高航天航空网络传输性能,针对低轨空间舱内有效载荷系统的特点及有效载荷系统数据传输的要求,将空间有效载荷系统的数据分为周期性业务、突发性业务及强时效性业务3种业务类型,并综合分析3种业务特征,提出了一种可应用于FC-AE-1553... 详细信息

为提高航天航空网络传输性能,针对低轨空间舱内有效载荷系统的特点及有效载荷系统数据传输的要求,将空间有效载荷系统的数据分为周期性业务、突发性业务及强时效性业务3种业务类型,并综合分析3种业务特征,提出了一种可应用于FC-AE-1553网络的"并发交换式"动态带宽调度(DBA)机制,即突发性业务传输采用"并发交换式"的动态带宽分配,周期性业务采用静态固定带宽分配,强时效性业务采用抢占式带宽分配的方案。采用理论分析和仿真验证的方式分析了该调度机制的可行性,并通过OPNET仿真软件建立了FCAE-1553网络仿真平台。结果表明,相比FC-AE-1553网络传统的"总线式"调度机制,所提机制可将FC-AE-1553网络的吞吐量提高10倍以上,且当网络节点数为32时,FC-AE-1553网络的吞吐量可从2.8 Gb/s提高到46 Gb/s,突发性业务的平均时延可降低1个数量级。

关键词：交换式FC-AE-1553网络周期性可并发动态调度机制吞吐量时延