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circMAN1A2调节miR-212-3p/DDIT4轴对胃癌细胞增殖、侵袭和迁移的影响
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作者 曹博威 贾腾飞 +2 位作者 宋钉町 赵昱清 张文斌 《胃肠病学和肝病学杂志》 CAS 2024年第7期868-874,共7页
目的探究circMAN1A2靶向miR-212-3p/DNA损伤诱导转录子4(NDA damage-inducible transcript 4,DDIT4)轴对胃癌细胞增殖、侵袭和迁移的影响。方法qRT-PCR法检测胃癌组织和细胞中circMAN1A2、miR-212-3p表达水平。荧光素酶检测circMAN1A2与... 目的探究circMAN1A2靶向miR-212-3p/DNA损伤诱导转录子4(NDA damage-inducible transcript 4,DDIT4)轴对胃癌细胞增殖、侵袭和迁移的影响。方法qRT-PCR法检测胃癌组织和细胞中circMAN1A2、miR-212-3p表达水平。荧光素酶检测circMAN1A2与miR-212-3p、DDIT4和miR-212-3p的靶向关系。在胃癌细胞SGC-7901、HGC-27中转染si-NC、si-circMAN1A2、si-circMAN1A2+anti-NC、si-circMAN1A2+anti-miR-212-3p、miR-NC、miR-212-3p mimics,将未转染的SGC-7901、HGC-27细胞设为对照。平板克隆实验检测细胞增殖;细胞划痕及Transwell实验分别检测细胞迁移、侵袭能力。Western blotting检测增殖、迁移及侵袭相关蛋白表达。结果在胃癌组织及细胞中,circMAN1A2高表达,miR-212-3p低表达;下调circMAN1A2可以靶向上调miR-212-3p表达,且下调DDIT4表达,进而抑制胃癌细胞增殖、侵袭和迁移能力。抑制miR-212-3p表达可部分逆转抑制circMAN1A2表达对胃癌细胞恶性增殖的抑制作用。结论在胃癌细胞中抑制circMAN1A2表达可抑制胃癌细胞增殖、迁移与侵袭,其与调节miR-212-3p/DDIT4信号轴有关。 展开更多
关键词 环状RNA man1A2 微小RNA-212-3p DNA损伤诱导转录子4 胃癌 增殖 侵袭 迁移
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Utilization Survey of Livestock Manure Resources in Large-scale Farms of Yangzhou
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作者 ZHANG Yue-ping MAO Wei LI Wen-xi 《Animal Husbandry and Feed Science》 CAS 2013年第1期37-40,49,共5页
Based on surveying the conditions of large -scale farms and commercial manure in the each county of Yangzhou city, the situations and problems for utilization of livestock manure resources were grasped. After an analy... Based on surveying the conditions of large -scale farms and commercial manure in the each county of Yangzhou city, the situations and problems for utilization of livestock manure resources were grasped. After an analysis of the potential value of livestock manure, the suggestion and strategy for utilization of livestock manure resources were proposed based on the actual conditions in Yangzhou city. 展开更多
关键词 Large - scale farms Livestock manure resources utilization
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The Coupling Coordination Evolution Research of Economy - Ecology - Society System in Xinjiang:Based on the Interaction Perspective of Water Resources 被引量:1
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作者 Chen Junke Li Hong +1 位作者 Wang Xibo Ma Yongren 《Meteorological and Environmental Research》 CAS 2017年第5期73-77,共5页
Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-econo... Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-economy-ecology-society system,quantitative evaluation and analysis of the coupling coordination of the water resources-economy-ecology-society system from 2001 to 2014 were conducted. The results showed that benefit indexes of economic system and social system grew rapidly,while benefit indexes of water resources system and ecosystem fluctuated smoothly from 2001 to 2014; coupling state of the whole system was at rival stage,and coupling coordination was reluctant coordination type,and the coupling index was slightly higher than the coupling coordination index. Moreover,it showed that the more the coupling systems,the lower indices of coupling and the coupling coordination. 展开更多
关键词 Water resources - ECONOMY - ECOLOGY - SOCIETY SYSTEM COUPLING coordination Evolution XINJIANG
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2015 IWA Alternative Water Resources Conference Nanjing,China(May 26-28,2015)
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《Water Science and Engineering》 EI CAS CSCD 2015年第2期174-174,共1页
The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Rese... The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Research Center of Hohai University. 展开更多
关键词 IWA Alternative Water resources Conference Nanjing China May 26-28 2015
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基于FTA原理的MAN B&W 50-90MC主机电气操纵系统故障停车研究
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作者 刘建安 《中国修船》 2015年第4期50-53,56,共5页
文章对于船舶MAN B&W 50-90MC主机电气操纵系统故障停车问题,利用故障树分析(FTA)原理进行定性和定量的可靠性分析,得出关于故障停车的底事件的重要度排序,明确此系统的可靠性薄弱环节,提出预防性建议,帮助船舶轮机管理和航运公司... 文章对于船舶MAN B&W 50-90MC主机电气操纵系统故障停车问题,利用故障树分析(FTA)原理进行定性和定量的可靠性分析,得出关于故障停车的底事件的重要度排序,明确此系统的可靠性薄弱环节,提出预防性建议,帮助船舶轮机管理和航运公司机务管理人员能迅速、可以准确利用系统的故障现象定位故障源并提出解决方案,从而使系统故障可以迅速排除并恢复系统正常功能。 展开更多
关键词 故障树分析原理 故障停车 man B&W 50-90MC主机电气控制系统 顶事件 底事件 结构重要度 最小割集
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Economic appraisal of shale gas resources, an example from the Horn River shale gas play, Canada 被引量:2
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作者 Zhuoheng Chen Kirk G.Osadetz Xuansha Chen 《Petroleum Science》 SCIE CAS CSCD 2015年第4期712-725,共14页
Development of unconventional shale gas resources involves intensive capital investment accompa- nying large commercial production uncertainties. Eco- nomic appraisal, bringing together multidisciplinary project data ... Development of unconventional shale gas resources involves intensive capital investment accompa- nying large commercial production uncertainties. Eco- nomic appraisal, bringing together multidisciplinary project data and information and providing likely economic outcomes for various development scenarios, forms the core of business decision-making. This paper uses a dis- counted cash flow (DCF) model to evaluate the economic outcome of shale gas development in the Horn River Basin, northeastern British Columbia, Canada. Through numerical examples, this study demonstrates that the use of a single average decline curve for the whole shale gas play is the equivalent of the results from a random drilling process. Business decision based on a DCF model using a single decline curve could be vulnerable to drastic changes of shale gas productivity across the play region. A random drilling model takes those drastic changes in well estimated ultimate recovery (EUR) and decline rates into account in the economic appraisal, providing more information useful for business decisions. Assuming a natural gas well-head price of S4/MCF and using a 10 % discount rate, the results from this study suggest that a random drilling strategy (e.g., one that does not regard well EURs), could lead to a negative net present value (NPV); whereas a drilling sequence that gives priority to developing those wells with larger EURs earlier in the drilling history could result in a positive NPV with various payback time and internal rate of return (IRR). Under a random drilling assumption, the breakeven price is S4.2/MCF with more than 10 years of payout time. In contrast, if the drilling order is strictly proportional to well EURs, the result is a much better economic outcome with a breakeven price below the assumed well-head price accompanied by a higher IRR. 展开更多
关键词 Drilling order EUR Risk aversion - Shalepetroleum resource
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Assessment of acoustic backscatter intensity surveying on deep-sea ferromanganese crust: Constraints from Weijia Guyot, western Pacific Ocean 被引量:3
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作者 Hui-qiang Yao Yong-gang Liu +5 位作者 Yong Yang Jin-feng Ma Huo-Dai Zhang Jiang-bo Ren Xi-guang Deng Gao-wen He 《China Geology》 2021年第2期288-298,共11页
Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate typ... Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate types were identified:Sediment,ferromanganese crust,and ferromanganese crust with a thin cover of sediment.The ferromanganese crusts show clear zoning and their continuity is usually disturbed by sediments on areas of the mountainside with relatively gentle slope gradients.The identified substrate spatial distributions correspond to acoustic backscatter intensity data,with regions of high intensity always including crust development and regions of low intensity always having sediment.Therefore,acoustic backscatter intensity surveying appears useful in the delineation and evaluation of crust resources,although further more work is needed to develop a practicable methodology. 展开更多
关键词 Ferromanganese crust SEAMOUNT Acoustic backscatter intensity manned deep submersible Jiaolong resource exploration and assessment Magellan Seamounts Marine geological survey engineering Western Pacific Ocean
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The concept and the accumulation characteristics of unconventional hydrocarbon resources 被引量:6
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作者 Yan Song Zhuo Li +1 位作者 Lin Jiang Feng Hong 《Petroleum Science》 SCIE CAS CSCD 2015年第4期563-572,共10页
Unconventional hydrocarbon resources, which are only marginally economically explored and developed by traditional methods and techniques, are different from conventional hydrocarbon resources in their accumulation me... Unconventional hydrocarbon resources, which are only marginally economically explored and developed by traditional methods and techniques, are different from conventional hydrocarbon resources in their accumulation mechanisms, occurrence states, distribution models, and exploration and development manners. The types of unconventional hydrocarbon are controlled by the evolu- tion of the source rocks and the combinations of different types of unconventional reservoirs. The fundamental dis- tinction between unconventional hydrocarbon resources and conventional hydrocarbon resources is their non- buoyancy-driven migration. The development of the micro- to nano-scale pores results in rather high capillary resis- tance. The accumulation mechanisms of the unconven- tional and the conventional hydrocarbon resources are also greatly different. In conventional hydrocarbon resources, oil and gas entrapment is controlled by reservoir-forming factors and geological events, which is a dynamic balance process; while for unconventional hydrocarbon resources, the gas content is affected by the temperature and pressure fields, and their preservation is crucial. Unconventional and conventional hydrocarbons are distributed in an orderly manner in subsurface space, having three distribution models of intra-source rock, basin-centered, and source rock interlayer. These results will be of great significance to unconventional hydrocarbon exploration. 展开更多
关键词 Unconventional hydrocarbon resources - Non-buoyancy-driven accumulation. Accumulationmechanisms ~ Distribution model
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A user-oriented resource scheduling method for improving agile software pattern in cloud environment
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作者 龙飞 杨昌 +1 位作者 荣辉桂 李建方 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2906-2916,共11页
The crowdsourcing, as a service pattern in cloud environment, usually aims at the cross-disciplinary cooperation and creating value together with customers and becomes increasingly prevalent. Software process, as a ki... The crowdsourcing, as a service pattern in cloud environment, usually aims at the cross-disciplinary cooperation and creating value together with customers and becomes increasingly prevalent. Software process, as a kind of software development and management strategy, is defined as a series of activities implemented by software life cycle and provides a set of rules for various phases of the software engineering to achieve the desired objectives. With the current software development cycle getting shorter, facing more frequent needs change and fierce competition, a new resource management pattern is proposed to respond to these issues agilely by introducing the crowdsourcing service to agile software development for pushing the agility of software process. Then, a user-oriented resource scheduling method is proposed for rational use of various resources in the process and maximizing the benefits of all parties. From the experimental results, the proposed pattern and resources scheduling method reduces greatly the resource of project resource manager and increases the team resource utilization rate, which greatly improves the agility of software process and delivers software products quickly in crowdsourcing pattern. 展开更多
关键词 resource scheduling agile software development project resource manager(PRM) individual resource provider(IRP)-
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Subsolidus Conceptual Design of CaO-AI_2O_3-TiO_2-SiO_2 System and Its Significance for Manufacturing Advanced Ceramics
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作者 Michail I. RYSCHENKO Yaroslav N. PITAK +2 位作者 Elena Yu. FEDORENKO Maria Yu. LISYUTKINA Alexey V. SHEVTSOV 《China's Refractories》 CAS 2016年第1期44-52,共9页
The article deals the structure of the CaO -Al2O3 - TiO2 -SiO2 system as a basis for obtaining advanced ce- ramics with a complex of high-operational characteris- tics. As a result o['investigations the phase charctc... The article deals the structure of the CaO -Al2O3 - TiO2 -SiO2 system as a basis for obtaining advanced ce- ramics with a complex of high-operational characteris- tics. As a result o['investigations the phase charctcteristics are represented trod the graph of the relationship of the elementaory tetrahedra has been plotted. The most techno- logical system area ,for the production of heat resistant advanced ceramics has been determined. The batches for producing heat and chemical resistant dense advanced ceramics made of natural, technical and technogenic raw materials have been developed. 展开更多
关键词 geometric - topological characteristics thermodynamic analysis resource conservation ceramic eomprising tialite sintering processes phase formation
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载人月球探测科学研究发展概述与趋势分析
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作者 张鹏 代巍 +9 位作者 白一帆 张光 牛冉 刘成保 王之 郑海菠 杨瀚哲 刘光辉 刘欣 童小华 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期1188-1198,共11页
月球是具有重要科学价值与战略价值的自然天体,开展载人月球探测,实现中国人首次登陆地外天体,将成为航天强国建设的重要标志。在载人月球探测过程中,可利用月球特殊条件及资源,开展有人参与的科学研究活动,获取月球科学、月基科学和月... 月球是具有重要科学价值与战略价值的自然天体,开展载人月球探测,实现中国人首次登陆地外天体,将成为航天强国建设的重要标志。在载人月球探测过程中,可利用月球特殊条件及资源,开展有人参与的科学研究活动,获取月球科学、月基科学和月球资源利用等方面的研究成果。首先回顾了阿波罗计划、阿尔忒弥斯计划、嫦娥工程等月球探测任务,针对其中的科学研究任务实施情况及关键成果进行了总结,并分析了后续载人月球科学任务发展趋势。在此基础上,对人类在开展未来载人月球探测任务过程中重点部署的方向提出了建议,涉及月球样品采集、月球科学探测,以及月球原位资源利用等方面。对载人月球探测科学研究发展趋势的分析及建议,可为未来载人登月相关论证设计提供参考。 展开更多
关键词 载人月球探测 科学研究与应用 月球样品采集 月球科学探测 原位资源利用
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习近平生态文明思想的生成基础和实践要求 被引量:1
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作者 潘莹 《哈尔滨学院学报》 2024年第4期1-5,共5页
习近平生态文明思想是我国社会主义生态文明建设的指导思想,是习近平新时代中国特色社会主义思想的重要组成部分。习近平生态文明思想的生成基础,始于现实需要,助力新时代生态经济转型;孕于传统文化,是对古代生态智慧的守正创新;基于国... 习近平生态文明思想是我国社会主义生态文明建设的指导思想,是习近平新时代中国特色社会主义思想的重要组成部分。习近平生态文明思想的生成基础,始于现实需要,助力新时代生态经济转型;孕于传统文化,是对古代生态智慧的守正创新;基于国情特点,具有鲜明中国特色。在实践要求上,习近平生态文明思想强调,坚定生态信念,将生态文明建设提升至国家战略高度,并纳入“五位一体”和中国式现代化建设;坚持生态优先,将绿色发展融入新发展理念,寻求经济与生态协调发展路径;坚守生态为民,以人民为中心,着力解决生态环境与民生问题的紧密联系,倡导全社会共同参与环保行动,以实现中华民族永续发展的宏伟目标。 展开更多
关键词 习近平 生态文明思想 自然资源 人与自然
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黑曲霉MAN1基因在大肠杆菌中的表达及酶学性质分析
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作者 张旭 李璐 +2 位作者 曹雨婷 徐欣 李杰 《东北农业大学学报》 CAS CSCD 北大核心 2011年第12期91-96,共6页
为了通过基因工程的方法在大肠杆菌中生产β-甘露聚糖酶。以β-甘露聚糖酶生产菌黑曲霉为材料,通过RT-PCR扩增获得β-甘露聚糖酶基因MAN1的cDNA片段,将该片段克隆连至pMD18-T并测序。Blast比对结果表明,该序列与GenBank中编号XM00140005... 为了通过基因工程的方法在大肠杆菌中生产β-甘露聚糖酶。以β-甘露聚糖酶生产菌黑曲霉为材料,通过RT-PCR扩增获得β-甘露聚糖酶基因MAN1的cDNA片段,将该片段克隆连至pMD18-T并测序。Blast比对结果表明,该序列与GenBank中编号XM001400053的序列相似性为100%,将pMD18-MAN1与PET-32b进行双酶切后连接,构建原核表达载体pET-MAN1。酶切鉴定正确后,将该载体导入大肠杆菌BL21。重组菌株经IPTG诱导表达,将表达产物进行SDS-PAGE,并用DNS法的测定不同温度、不同pH下该融合蛋白的甘露聚糖酶活性。结果表明,经IPTG诱导,转化得到约62 ku的融合蛋白条带,IPTG最佳诱导表达时间是6 h,融合蛋白质以可溶组分形式存在。经DNS测定,重组甘露聚糖酶的最适温度为55℃,最适pH为5.5,在此条件下,甘露聚糖酶活力为48 IU.mL-1。研究结果以期为甘露聚糖酶的工业化生产探索新的途径。 展开更多
关键词 Β-甘露聚糖酶 man1 大肠杆菌 克隆
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Regulating the Electron-Deficient Component in A-DA1D-A Typed Small-Molecule Acceptors for High-Performance Organic Solar Cells
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作者 Weifei Wei Ruijie Ma +3 位作者 Zhanxiang Chen Tongle Xu Gang Li Zhenghui Luo 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第6期623-630,共8页
Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]... Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]thieno[2,3-b]quinoxaline,designated as QW1,as well as three SMAs based on 1-methylindoline-2,3-dione,identified as QW2,QW3,and QW4.Compared with QW2,QW1 displays slightly blue-shifted absorption spectra and a lower LUMO energy level due to the stronger electron-withdrawing capability of BTQx in contrast to MDO.On the other hand,the introduction of a bromine atom in QW3 and QW4 causes a blue shift in absorption and a reduction in the LUMO energy level compared to QW2.Density functional theory analysis reveals that QW1 exhibits the best molecular planarity,which endows QW1 with larger electron mobility and tighter molecular stacking.Consequently,PM6:QW1 device affords a better efficiency of 15.63% than those of the devices based on QW2 (14.25%),QW3 (13.21%) and QW4 (15.03%).Moreover,the QW4-based device yields the highest open-circuit voltage of 0.933 V,and the PM6:L8-BO:QW4 ternary device realizes a PCE of 19.03%.Overall,our work demonstrates that regulation of electron-deficient central units is an effective strategy to improve the photovoltaic performance of the resulting A-DA1D-A SMAs. 展开更多
关键词 Organic solar cells Small-molecule acceptor Electron-deficient unit Energy conversion efficiency Renewable resources π-πstacking Green chemistry
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基于护理分级和工时测定的新生儿监护病房护理人力资源的配置研究
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作者 陈筱璇 张媛媛 王芬 《妇儿健康导刊》 2024年第12期177-180,共4页
目的 探讨基于护理分级和工时测定的新生儿监护病房护理人力资源的配置。方法 采用护理工时测定计算表,于2022年12月至2023年3月测算南京大学医学院附属鼓楼医院(我院)新生儿监护病房13名护士各项护理操作时间,统计连续2周共224例患儿... 目的 探讨基于护理分级和工时测定的新生儿监护病房护理人力资源的配置。方法 采用护理工时测定计算表,于2022年12月至2023年3月测算南京大学医学院附属鼓楼医院(我院)新生儿监护病房13名护士各项护理操作时间,统计连续2周共224例患儿各类护理项目次数,计算新生儿监护病房不同护理等级人均每日护理时间和理论床护比。结果 新生儿监护病房特级护理人均每日活动总工时为450.45 min,一级护理人均每日活动总工时为365.88 min;新生儿监护病房人均每日护理时间为377.96 min,理论护士人数为28名,实际护士数13名,适宜床护比为1∶1.75,实际床护比为1∶0.81;同一护理操作,护士能级越高者单次耗时越短。结论 我院新生儿监护病房护理人力资源配置有待提高,应根据护理分级,每日分配不同能级的护士进行管理,以合理配置和利用临床护理人力资源。 展开更多
关键词 护理分级 工时测定 新生儿监护病房 护理人力资源配置
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生成式人工智能赋能高校思政课教学探析
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作者 孙静宜 《湖北职业技术学院学报》 2024年第4期36-41,共6页
高校思政课教学改革应果断抓住生成式人工智能浪潮带来的发展契机,破除传统思政课教学弊端,扩展教学场域,丰富教学资源,实现精准施教,完善教学评价,构建思政教学新图景。然而,生成式人工智能与思政课教学在教学内容、信息安全以及价值... 高校思政课教学改革应果断抓住生成式人工智能浪潮带来的发展契机,破除传统思政课教学弊端,扩展教学场域,丰富教学资源,实现精准施教,完善教学评价,构建思政教学新图景。然而,生成式人工智能与思政课教学在教学内容、信息安全以及价值引领等方面的内在张力也使得赋能任务面临障碍。因此,需要从提升人机协同能力、提高主体素养、完善技术生态、明确算法责任主体、加强技术监管、锚定主流价值导向等方面入手,助力思政课教学效果向善向好。 展开更多
关键词 生成式人工智能 思政课 人机协同 教学资源
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Modelling of Quasi 3-D Groundwater Flow and Studying of Equivalent Drainage Boundary in Beihai Peninsula,Guangxi 被引量:2
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作者 Chen Chongxi Lin Min Li GuominChina University of Geosciences , Wuhan 430074Jiang Jianmin Ye Shanshi Wu NaidongGeology Bureau of Guangxi Autonomous Region , Naming 530023 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期109-119,共11页
This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through th... This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through the aquitard . It is applied to evaluate the maximum rate of groundwater resources exploited from the coastal aquifer without seawater intrusion . The main task in this model is to determine the drainage boundary of the aquifer extending under the sea . The information of the boundary can be obtained from the fluctuations of the groundwater level caused by sea-tide fluctuations . A new idea, Equivalent Drainage Boundary (EDB), is proposed and the corresponding methods , determining the EDB, are developed with tidal fluctuations data observed in boreholes . The quasi 3-D model and the methods determining EDB have been applied to the aquifer system of Beihai peninsula , Guangxi Autonomous Region of China for calculating the available groundwater resources . 展开更多
关键词 quad 3 - D model coastal aquifer Equivalent Drainage Boundary available groundwater resources Beihai peninsula .
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α-甘露糖苷贮积症的分子遗传学及其在临床诊断与防治方面的意义
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作者 吴晓昀 张杰 郭奕斌 《分子诊断与治疗杂志》 2013年第4期261-267,共7页
MAN2B1基因突变导致α-甘露糖苷酶缺乏或活性降低是引起α-甘露糖苷贮积症的根本内因。对MAN2B1基因、LAMAN酶的结构和功能的研究、基因型与表现型的相关性研究以及诊防治方面的研究近年来都取得了诸多新进展。本文重点围绕这几方面作... MAN2B1基因突变导致α-甘露糖苷酶缺乏或活性降低是引起α-甘露糖苷贮积症的根本内因。对MAN2B1基因、LAMAN酶的结构和功能的研究、基因型与表现型的相关性研究以及诊防治方面的研究近年来都取得了诸多新进展。本文重点围绕这几方面作一综述。 展开更多
关键词 α-甘露糖苷贮积症 man2B1基因 α-甘露糖苷酶 溶酶体α-D-甘露糖苷酶 分子遗传学
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A Hybrid Dynamic Programming Method for Concave Resource Allocation Problems
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作者 姜计荣 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期95-98,共4页
Concave resource allocation problem is an integer programming problem of minimizing a nonincreasing concave function subject to a convex nondecreasing constraint and bounded integer variables. This class of problems a... Concave resource allocation problem is an integer programming problem of minimizing a nonincreasing concave function subject to a convex nondecreasing constraint and bounded integer variables. This class of problems are encountered in optimization models involving economies of scale. In this paper, a new hybrid dynamic programming method was proposed for solving concave resource allocation problems. A convex underestimating function was used to approximate the objective function and the resulting convex subproblem was solved with dynamic programming technique after transforming it into a 0-1 linear knapsack problem. To ensure the convergence, monotonicity and domain cut technique was employed to remove certain integer boxes and partition the revised domain into a union of integer boxes. Computational results were given to show the efficiency of the algorithm. 展开更多
关键词 nonlinear integer programming resource allocation linear underestimation 0-1linearization dynamic programming.
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Analysis on mechanism of land resource security
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作者 Bao Haijun 《Ecological Economy》 2008年第2期236-242,共7页
This paper prohes into the relationship among individual benefits, benefits of the country. common benefits of all humans in land use and land resource security. The following balanced land use model is proposed: the... This paper prohes into the relationship among individual benefits, benefits of the country. common benefits of all humans in land use and land resource security. The following balanced land use model is proposed: the harmonious and interactive relationship between man and nature, two main bodies of land ecological system, constitutes the mechanism of land resources security; The feedback relationship between man and nature is the basis for the land resources security and the core is the relationship among people established for the benefit equilibrium in land use. The conflicts in land use stem from the rarity of land resource and the solution to those conflicts in harmony helps land resource security. 展开更多
关键词 man and nature Land use Land resource Land resource security
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