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Activities of Biapenem against Mycobacterium tuberculosis in Macrophages and Mice 被引量:1
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作者 GUO Zhen Yong ZHAO Wei Jie +4 位作者 ZHENG Mei Qin LIU Shuo YAN Chen Xia LI Peng XU Shao Fa 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第4期235-241,共7页
Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Myc... Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Mycobacterium tuberculosis(Mtb) multidrug-resistant(MDR) isolates, extensively drug-resistant(XDR) isolates, and the H37 RV strain. BP/CL activity against the H37 Rv strain was assessed in liquid cultures, in macrophages, and in mice. Results BP/CL exhibited activity against MDR and XDR Mtb isolates in liquid cultures. BP/CL treatment significantly reduced the number of colony forming units(CFU) of Mtb within macrophages compared with control untreated infected macrophages. Notably, BP/CL synergized in pairwise combinations with protionamide, aminosalicylate, and capreomycin to achieve a fractional inhibitory concentration for each pairing of 0.375 in vitro. In a mouse tuberculosis infection model, the efficacy of a cocktail of levofloxacin + pyrazinamide + protionamide + aminosalicylate against Mtb increased when the cocktail was combined with BP/CL, achieving efficacy similar to that of the positive control treatment(isoniazid + rifampin + pyrazinamide) after 2 months of treatment. Conclusion BP/CL may provide a new option to clinically treat MDR tuberculosis. 展开更多
关键词 BIAPENEM CLAVULANATE MULTIDRUG resistant extensive DRUG-RESISTANT MYCOBACTERIUM tuberculosis activity Macrophage Synergy
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A dual-period response of the Kuroshio Extension SST to Aleutian Low activity in the winter season 被引量:1
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作者 YU Peilong ZHANG Lifeng +2 位作者 LIU Hu LIU Xing ZHU Juan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期1-9,共9页
Based on our previous work, the winter sea surface temperature(SST) in the Kuroshio Extension(KE) region showed significant variability over the past century with periods of ~6 a between 1930 and 1950 and ~10 a be... Based on our previous work, the winter sea surface temperature(SST) in the Kuroshio Extension(KE) region showed significant variability over the past century with periods of ~6 a between 1930 and 1950 and ~10 a between1980 and 2009. How the activity of the Aleutian Low(AL) induces this dual-period variability over the two different timespans is further investigated here. For the ~6 a periodicity during 1930–1950, negative wind stress curl(WSC)anomalies in the central subtropical Pacific associated with an intensified AL generate positive sea surface height(SSH) anomalies. When these wind-induced SSH anomalies propagate westwards to the east of Taiwan, China two years later, positive velocity anomalies appear around the Kuroshio to the east of Taiwan and then the mean advection via this current of velocity anomalies leads to a strengthened KE jet and thus an increase in the KE SST one year later. For the ~10 a periodicity during 1980–2009, a negative North Pacific Oscillation-like dipole takes2–3 a to develop into a significant positive North Pacific Oscillation-like dipole, and this process corresponds to the northward shift of the AL. Negative WSC anomalies associated with this AL activity in the central North Pacific are able to induce the positive SSH anomalies. These oceanic signals then propagate westward into the KE region after 2–3 a, favoring a northward shift of the KE jet, thus leading to the warming of the KE SST. The feedbacks of the KE SST anomaly on the AL forcing are both negative for these two periodicities. These results suggest that the dual-period KE SST variability can be generated by the two-way KE-SST-AL coupling. 展开更多
关键词 sea surface temperature Kuroshio extension Aleutian Low activity dual-period variability
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International Conference on Sustainable Rice Production - Policy, Technology and Extension Celebration Activity for International Year of Rice and World Food Day 2004 被引量:1
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作者 Approved and Supported by The Ministry of Agriculture of China and $The Chinese Academy of Agricultural Sciences Co-Organized by China National Rice Research Institute and Beijing Green Vision Ecosciences Inc. (Member of CK Life Sciences Gropu, Hong Kong) 《Rice science》 SCIE 2004年第3期150-151,共2页
Rice is the staple food of more than half of the world’s Population.The production,processing and management of paddy rice have provided the basic conditions for the living of mankind.The production of rice has not o... Rice is the staple food of more than half of the world’s Population.The production,processing and management of paddy rice have provided the basic conditions for the living of mankind.The production of rice has not only created 展开更多
关键词 International Conference on Sustainable Rice Production Policy Technology and extension Celebration activity for International Year of Rice and World Food Day 2004 World activITY
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A Novel Active Network Architecture Based on Extensible Services Router
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作者 徐恪 XU +4 位作者 Mingwei Wu Jianping Yu Zhongchao 《High Technology Letters》 EI CAS 2003年第2期51-56,共6页
Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a net... Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a network. In this paper, the authors present a novel active network architecture combined with advantages of two major active networks technology based on extensible services router. The architecture consists of extensible service router, active extensible components server and key distribution center (KDC). Users can write extensible service components with programming interface. At the present time, we have finished the extensible services router prototype system based on Highly Efficient Router Operating System (HEROS), active extensible components server and KDC prototype system based on Linux. 展开更多
关键词 computer networks extensible services active network AUTHENTICATION
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Clinical value of ankle flexion and extension exercises combined with a psychological intervention in knee osteoarthritis 被引量:1
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作者 Yang Liu Rong Chen +4 位作者 Yang Zhang Qin Wang Jiang-Li Ren Chang-Xu Wang Yuan-Kun Xu 《World Journal of Psychiatry》 SCIE 2023年第10期743-752,共10页
BACKGROUND Considering the limited effectiveness of clinical interventions for knee osteoarthritis(KOA),it is necessary to continue to explore appropriate and effective treatment strategies to improve the condition of... BACKGROUND Considering the limited effectiveness of clinical interventions for knee osteoarthritis(KOA),it is necessary to continue to explore appropriate and effective treatment strategies to improve the condition of KOA patients.AIM To clarify the influence of ankle flexion and extension exercises combined with a psychological intervention on the psychological status and activities of daily living(ADLs)of patients with KOA.METHODS The research participants were 116 KOA patients admitted to The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine between May 2019 and May 2022,including 54 patients receiving routine treatment,care and psychological intervention(control group)and 62 patients additionally treated with ankle flexion and extension exercises(research group).The two groups were comparatively analyzed in terms of psychological status(Self-rating Anxiety/Depression Scale,SDS/SAS),ADLs,knee joint function(Lysholm Knee Scoring Scale),pain(Visual Analog Scale,VAS),fatigue(Multidimensional Fatigue Inventory,MFI),and quality of life(QoL;Short-Form 36 Item Health Survey,SF-36).RESULTS After evaluation,it was found that the postinterventional SDS,SAS,VAS,and MFI scores in the research group were significantly reduced compared with the baseline(before the intervention)values and those of the control group,while the postinterventional Lysholm,ADL and SF-36 scores were markedly elevated.CONCLUSION Therefore,ankle flexion and extension exercises are highly effective in easing negative psychological status,enhancing ADLs,daily living ability,knee joint function and QoL,and relieving pain and fatigue in KOA patients,thus warranting clinical promotion. 展开更多
关键词 Ankle flexion and extension exercises Knee osteoarthritis PSYCHOLOGY Negative emotions activities of daily living Quality of life
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矿物掺合料在活性粉末混凝土(RPC)中应用研究
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作者 王蓓 王彦 《混凝土》 CAS 北大核心 2024年第10期167-170,177,共5页
矿物掺合料作为一种重要材料在混凝土中应用,为研究矿物掺合料对活性粉末混凝土(RPC)性能影响,以及应用的可行性,将矿物掺合料复配到C120 RPC中,研究对RPC的性能影响规律及得到最佳胶凝材料体系。结果表明:(1)最小基本需水量、标准稠度... 矿物掺合料作为一种重要材料在混凝土中应用,为研究矿物掺合料对活性粉末混凝土(RPC)性能影响,以及应用的可行性,将矿物掺合料复配到C120 RPC中,研究对RPC的性能影响规律及得到最佳胶凝材料体系。结果表明:(1)最小基本需水量、标准稠度需水量试验得到矿物掺合料最佳掺量,水泥∶超细矿粉∶硅灰∶粉煤灰=0.7∶0.1∶0.1∶0.1。(2)超细矿粉对RPC 3 d、7 d强度影响明显,分别最大提高6 MPa、13.5 MPa;硅灰对RPC 28 d强度影响明显,最大提高2.2 MPa;粉煤灰对RPC扩展度影响明显,最大提高71 mm。(3)研究确定RPC中四元胶凝体系,即水泥∶超细矿粉∶硅灰∶粉煤灰=0.7∶0.1∶0.1∶0.1,RPC坍落度370 mm,扩展度615 mm,28 d抗压强度128.47 MPa,抗硫酸盐侵蚀等级KS90。 展开更多
关键词 矿物掺合料 活性粉末混凝土(RPC) 扩展度 抗压强度 抗硫酸盐侵蚀
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基于多层次探测研究茅山断裂带北延段空间展布特征及第四纪活动性
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作者 孟科 张鹏 +2 位作者 范小平 王琛 汪晴慧 《地震科学进展》 2024年第9期559-569,共11页
本文介绍了从深至浅完成对茅山断裂北延立体式综合探测方法。使用重力场资料解译和大地电磁勘探初步定位断裂,随后通过浅层地震勘探进行精确定位,最后根据跨断点的小间距钻孔联合地质剖面探测法捕获了上断点并研判其第四纪活动性。研究... 本文介绍了从深至浅完成对茅山断裂北延立体式综合探测方法。使用重力场资料解译和大地电磁勘探初步定位断裂,随后通过浅层地震勘探进行精确定位,最后根据跨断点的小间距钻孔联合地质剖面探测法捕获了上断点并研判其第四纪活动性。研究发现:①茅山断裂带继续向北延伸入镇江市区,茅山断裂带北延段切割深度至少延伸至中地壳区域;②茅山断裂带北延段浅部区域表现出正断性质,倾向东,走向北东,视倾角约为60°,视断距约为3~5 m;③钻孔联合地质剖面探测结果显示,断点两侧基岩面落差较小,上覆第四纪地层未发现较大的起伏,未见第四纪有明显活动迹象,综合判断茅山断裂带北延段为前第四纪断裂。本项研究初步表明,茅山断裂在地理空间上可能与江苏陆域历史上两次显著的地震事件存在联系。这一发现为进一步研究该地区的发震构造特征和地震活动规律提供了新的视角,并可能对今后的相关研究有所启发。 展开更多
关键词 茅山断裂带北延段 第四纪活动性 浅层地震勘探 钻孔联合剖面
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Site-directed Mutagenesis Based on Overlap Extension PCR 被引量:4
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作者 雒丽娜 王盛 王玉炯 《Agricultural Science & Technology》 CAS 2012年第4期719-722,共4页
[Objective] To establish an efficient, convenient and economical method for site-directed mutagenesis. [Method] The target mutation was introduced into primers designed by DNAMAN5.0 software. Through overlap extension... [Objective] To establish an efficient, convenient and economical method for site-directed mutagenesis. [Method] The target mutation was introduced into primers designed by DNAMAN5.0 software. Through overlap extension PCR for twice obtained the mutation gene which of the full length of the recombinant Human Tissue type plasminogen activator (Reteplase). The mutation gene cloned it into pEASY- blunt simple cloning vector for sequencing. [Result] The sequencing results showed that three site mutations were fully consistent with the expected results (10~ site had been added a base-pair of A, C had been changed into G at 137~ site, G had been changed into A at 686~ site).Three site mutations were introduced by using overlap extension PCR on one-step. The overall rate of obtaining the mutant sites was 100%. Site-directed mutagenesis will clone the recombinant Human Tissue type plas- minogen activator and laid the basis for the functional study. [Conclusion] Site-directed mutagenesis was successfully implemented based on the overlap extension PCR which is an efficient, convenient and economical DNA-directed mutagenesis method. 展开更多
关键词 Overlap extension PCR Site-directed mutagenesis Human Tissue Plas- minogen activator (Reteplase)
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岩石圈伸展的壳/幔拆离模型(Parallel Extension Tectonics):华北克拉通东部早白垩世岩石圈减薄与破坏机理 被引量:7
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作者 刘俊来 倪金龙 +4 位作者 陈小宇 Craddock JP 郑媛媛 孙彦琪 季雷 《岩石学报》 SCIE EI CAS CSCD 北大核心 2020年第8期2331-2343,共13页
华北克拉通岩石圈减薄和破坏机理长期以来存在争议,基于岩石学、岩石地球的化学分析研究突出强调深部过程的重要性。前人提出了两种重要模式:包括以拆沉作用为代表的top-down tectonics模型和以热-机械侵蚀与化学侵蚀,或地幔置换、交代... 华北克拉通岩石圈减薄和破坏机理长期以来存在争议,基于岩石学、岩石地球的化学分析研究突出强调深部过程的重要性。前人提出了两种重要模式:包括以拆沉作用为代表的top-down tectonics模型和以热-机械侵蚀与化学侵蚀,或地幔置换、交代作用的bottom-up tectonics模型。然而,对于这两种模式而言尚存在许多无法合理解释的问题,比如在此深部过程中,区域性岩石圈伸展有多大的贡献?地壳伸展构造是作为深部过程的响应,还是同为岩石圈伸展的产物?本文基于早白垩世东亚地区(尤其是华北克拉通东部地区)伸展构造与岩浆活动的综合分析,揭示出华北克拉通东部不同地区伸展构造变形与岩浆活动之间的时、空和成因关系有一定的差异。但整体上看,岩石圈伸展起着主导作用,控制着岩浆上侵和就位,在拆离断层下盘侵入形成各种规模的花岗质为主的侵入体,或于上盘喷发形成火山-沉积岩盆地。在伸展构造发育的不同阶段,可以有伸展早期、伸展期及伸展期后的岩浆活动。岩浆活动的强度及岩浆源区特点有显著的时空变化。一方面,在同一地区不同演化阶段其源区有很大的差异。表现为主体上是早期以古老下地壳源为主,随着壳/幔伸展作用演化,逐渐向混合源或独立幔源的演化。同时,不同地区岩浆源区的变化规律也显著不同。以胶辽地区为例,胶东整体上是壳幔混合源区对于岩浆演化有重要贡献;而辽东地区具有显著的源区演化特点:从剪切早期古老下地壳源区为主,并伴有幔源物质加入,剪切期古老下地壳为主,到剪切晚期和剪切期后以新生下地壳为主。本文认为岩石圈伸展的壳/幔拆离模型(Parallel Extension Tectonics),可以合理地解释华北克拉通及邻区早白垩世构造-岩浆活动性。在该模型中,遭受伸展的华北克拉通岩石圈发生壳-幔拆离作用。在岩石圈伸展作用期间,地壳层次的拆离作用与岩石圈地幔层次上的拆离作用可以是耦合的或者是解耦的,从而导致华北克拉通岩石圈减薄过程中在地壳尺度上的拆离作用与变质核杂岩的剥露有三种不同的类型:同岩浆活动型伸展(C型:Co-magmatism mode extension)、无岩浆活动型伸展(A型:Amagmatism mode extension)和多阶段混合型(M型:Multi-mode extension)。 展开更多
关键词 岩石圈不均匀伸展 壳幔拆离 同伸展岩浆作用 岩石圈伸展的壳幔拆离模型 华北克拉通
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导数推广的拉格朗日插值公式及其在密文训练神经网络中的应用 被引量:1
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作者 杨舒雅 李晓东 张健毅 《北京电子科技学院学报》 2024年第1期50-59,共10页
拉格朗日多项式插值公式被用于经过若干点的未知函数的多项式刻画,也被用于对已有的非多项式函数进行多项式函数逼近,在许多领域有着广泛的应用。本文探索了拉格朗日多项式插值公式在导数情况下的一般性推广。推广的多项式插值公式不仅... 拉格朗日多项式插值公式被用于经过若干点的未知函数的多项式刻画,也被用于对已有的非多项式函数进行多项式函数逼近,在许多领域有着广泛的应用。本文探索了拉格朗日多项式插值公式在导数情况下的一般性推广。推广的多项式插值公式不仅可以在插值点的函数值逼近目标函数,同时也能在插值点的变化趋势上对目标函数进行逼近。在已知插值点上给定某个阶数以内导数的情况下,能够使用推广的拉格朗日多项式插值公式获得对目标函数的深度多项式逼近。实验结果表明,用导数推广拉格朗日多项式代替逻辑回归函数重新构建的密文神经网络的训练准确率更高,均方误差更小。扩展后的拉格朗日多项式插值公式能够适用于更一般的场景。 展开更多
关键词 拉格朗日插值公式导数推广 密文训练神经网络 多项式逼近 激励函数
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Fish Gelatin-Based Film Containing Maillard Reaction Products:Properties and Its Use as Bag for Packing Chicken Skin Oil
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作者 Krisana Nilsuwan Yolanda Victoria Rajagukguk +2 位作者 Umesh Patil Thummanoon Prodpran Soottawat Benjakul 《Journal of Renewable Materials》 EI CAS 2024年第6期1125-1143,共19页
Maillard reaction is a non-enzymatic browning reaction and its products(MRPs)have been proven to possess antioxidant properties.This research aimed to produce a fish gelatin-based packaging incorporated with MRPs to r... Maillard reaction is a non-enzymatic browning reaction and its products(MRPs)have been proven to possess antioxidant properties.This research aimed to produce a fish gelatin-based packaging incorporated with MRPs to retard lipid oxidation in chicken skin oil(CSO)during storage at ambient temperature(28℃–30℃).MRPs produced from fish gelatin and fructose(1:1,90℃,pH 11)showed the highest antioxidant properties compared to those prepared under other conditions.Different glycerol/MRPs ratios(30:0,25:5,20:10,15:15,10:20,5:25,0:30)were incorporated into the film and resulting films were characterized.Glycerol/MRPs at 10:20 ratio was chosen to add into the film prior to bag preparation via heat sealing method.CSO packed in the bag was monitored for lipid hydrolysis and oxidation during 15 days of storage(30℃±0.5℃,RH 52%±5%).After 15 days,quality deterioration was lower in CSO packed in the prepared gelatin bag as evidenced by lower FFA,TBARS,and volatile compounds in comparison with CSO packed in LDPE bag.Fish gelatin film added with MRPs possessed an excellent water vapor barrier property(WV-BP).This finding indicated that MRPs could be used to substitute glycerol and simultaneously could serve as antioxidants for the developed active bag.The novel packaging can be a potential alternative packaging for retarding lipid oxidation of lipid or fatty foods. 展开更多
关键词 active film ANTIOXIDANT shelf-life extension Maillard reaction products fish gelatin
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极限工况下AFS与DYC可拓协调控制
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作者 冯樱 江子旺 +1 位作者 乔宝山 邓召文 《机械设计与制造》 北大核心 2024年第6期163-169,共7页
主动前轮转向系统(AFS)和直接横摆力矩控制(DYC)集成控制可提高商用货车的操纵稳定性。由于主动前轮转向在轮胎非线性区作用效果有限,与直接横摆力矩控制简单叠加的控制效果不一定能达到预期,为此这里设计了可拓协调控制系统。该系统分... 主动前轮转向系统(AFS)和直接横摆力矩控制(DYC)集成控制可提高商用货车的操纵稳定性。由于主动前轮转向在轮胎非线性区作用效果有限,与直接横摆力矩控制简单叠加的控制效果不一定能达到预期,为此这里设计了可拓协调控制系统。该系统分为上、中、下三层,上层为AFS与DYC协调切换控制层。采用试验法得到前轮临界转角,根据线性二自由度车辆模型反推临界转角下的稳态质心侧偏角,结合车辆实际质心侧偏角及其速度的相平面稳定域将相平面图分区,设计了3种不同协调控制策略;中层是基于指数趋近律设计的AFS与DYC滑模控制器,可得到前轮附加转角和附加横摆力矩;附加横摆力矩由下层控制器根据车辆实时状态进行制动力分配。采用TruckSim、Matlab/Simulink建立联合仿真平台,在极限工况下进行仿真验证可拓协调控制系统。仿真结果得到最优可拓协调策略,该协调控制弥补了AFS/DYC单一控制的缺陷,可保证车辆的操纵稳定性和行驶安全性。 展开更多
关键词 操纵稳定性 主动前轮转向 直接横摆力矩 相平面 前轮临界转角 可拓协调控制
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Low-frequency characteristics extension for vibration sensors 被引量:2
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作者 杨学山 高峰 候兴民 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第1期139-146,共8页
Traditional magneto-electric vibration sensors and servo accelerometers have severe shortcomings when used to measure vibration where low frequency components predominate.A low frequency characteristic extension for v... Traditional magneto-electric vibration sensors and servo accelerometers have severe shortcomings when used to measure vibration where low frequency components predominate.A low frequency characteristic extension for velocity vibration sensors is presented in this paper.The passive circuit technology,active compensation technology and the closed- cycle pole compensation technology are used to extend the measurable range and to improve low frequency characteristics of sensors.Thses three types of low frequency velocity vibration sensors have been developed and widely adopted in China. 展开更多
关键词 vibration sensor low frequency characteristic extension passive circuit technology active compensation technology closed-cycle pole compensation
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A Climatological Perspective on Extratropical Synoptic-Scale Transient Eddy Activity Response to Western Pacific Tropical Cyclones
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作者 Yao HA Zhong ZHONG +3 位作者 Haikun ZHAO Yimin ZHU Yao YAO Yijia HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第2期333-343,共11页
An observational study focusing on the contribution of tropical cyclones(TCs)that form over the western North Pacific(WNP)to the synoptic-scale transient eddy activity(STEA)over the North Pacific during the boreal aut... An observational study focusing on the contribution of tropical cyclones(TCs)that form over the western North Pacific(WNP)to the synoptic-scale transient eddy activity(STEA)over the North Pacific during the boreal autumn and early winter in the period 1979–2019 is presented in this paper.Statistical results show that WNP TCs entering the midlatitudinal North Pacific provide significant positive effects on the pentad mean strength of STEA,which is primarily concentrated over the Kuroshio/Oyashio Extensions(KOE)and regions from east of Japan to 160°W in the lower and midto-upper troposphere,respectively.TC intensity is highly indicative of the subsequent STEA with a correlation coefficient of 0.37/0.33/0.45 at 300 hPa/500 hPa/850 hPa exceeding the 99%confidence level for the period 1979–2019.The strength of STEA in the upper troposphere associated with TCs presents a more significant linear growth with TC intensity than that at the mid-to-lower levels after the cyclones enter the KOE region,suggesting that the impact of TCs on STEA gradually increases with height.Further analyses reveal that the contribution of TCs accounts for 4%–6%of the total STEA change over the KOE region during the late autumn and early winter.In addition,the influence of TCs on STEA experienced an interdecadal decrease from the early 2000 s through the early 2010 s. 展开更多
关键词 Synoptic-scale transient eddy activity tropical cyclone North Pacific Kuroshio/Oyashio extensions mid-latitudinal atmospheric motion
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早期康复治疗在大面积烧伤患者中的临床应用及疗效观察 被引量:1
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作者 张直群 王树 +1 位作者 邹同荣 李艳秋 《实用医院临床杂志》 2023年第6期161-164,共4页
目的观察早期康复治疗在大面积烧伤患者中的临床应用效果。方法选取2020年1月至2022年12月我院收治的120例大面积烧伤[总体表面积(TBSA)≥50%]患者,采用随机数字表法分为早期组和常规组各60例,两组均给予常规治疗及创面愈合后功能锻炼,... 目的观察早期康复治疗在大面积烧伤患者中的临床应用效果。方法选取2020年1月至2022年12月我院收治的120例大面积烧伤[总体表面积(TBSA)≥50%]患者,采用随机数字表法分为早期组和常规组各60例,两组均给予常规治疗及创面愈合后功能锻炼,早期组在此基础上进行早期康复干预。比较两组股四头肌肌力、肘关节和腕关节主动活动度、心理状态评分、生活质量评分。结果干预6个月后,两组股四头肌伸膝峰力矩(PT)、总做功量(TW)、平均功率(AP)均高于干预前,早期组股四头肌肌力指标高于常规组(P<0.05);干预1、3、6个月后,两组肘关节和腕关节主动活动度高于干预前,且早期组肘关节和腕关节主动活动度高于常规组(P<0.05);干预6个月后,两组抑郁自评量表(SDS)评分、焦虑自评量表(SAS)评分均低于干预前,且早期组心理状态评分低于常规组(P<0.05);两组躯体、心理、社会功能及一般健康状况评分均高于干预前,且早期组生活质量评分高于常规组(P<0.05)。结论早期康复治疗有利于最大限度恢复大面积烧伤患者关节功能,改善患者心理状况,提高患者肌力和生活质量。 展开更多
关键词 早期康复 大面积烧伤 心理状态 关节主动活动度 生活质量
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基于可拓决策法的车辆自适应避撞控制方法研究
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作者 陈翔 程硕 +2 位作者 赵万忠 王春燕 蒋睿 《力学学报》 EI CAS CSCD 北大核心 2023年第1期213-222,共10页
车辆的避撞控制可以有效避免或缓解车辆的碰撞事故,是自动驾驶汽车的关键控制技术之一.各种交通条件、不确定的道路附着系数以及复杂的液压制动执行系统都会降低避撞控制的有效性.因此,本文提出了一种基于可拓决策法的自适应避撞控制,... 车辆的避撞控制可以有效避免或缓解车辆的碰撞事故,是自动驾驶汽车的关键控制技术之一.各种交通条件、不确定的道路附着系数以及复杂的液压制动执行系统都会降低避撞控制的有效性.因此,本文提出了一种基于可拓决策法的自适应避撞控制,该控制方法对路面附着系数具有自适应性,并能够精确控制制动系统的制动液压力.首先,设计了滑模观测器来估计轮胎纵向力,并基于观测得到的轮胎纵向力,进一步提出带遗忘因子的递推最小二乘法估计道路附着系数.其次,基于递推最小二乘法的估计值,提出了基于路面附着系数自适应调节的自适应避撞控制方法,该方法基于可拓决策法的先决判定决定当前时刻应采用何种避撞控制策略,即采用可拓决策方法判断进行点刹预警制动、全制动或者不制动.再次,通过对执行系统-电控液压制动系统进行精确的液压控制,实现主动减速控制效果.最后,采用软件联合仿真手段对上述方法进行了验证,结果表明所提出的算法在避撞行驶工况中具有良好的避撞效果. 展开更多
关键词 自适应避撞控制 可拓决策法 道路附着系数估计 主动减速控制 液压制动
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OFDM系统中基于最优阈值ACE的PAPR抑制 被引量:1
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作者 吴群 周晓 王成优 《工程科学学报》 EI CSCD 北大核心 2023年第1期150-157,共8页
动态星座图扩展(Active constellation extension, ACE)是一种能够有效降低正交频分复用(Orthogonal frequency division multiplexing, OFDM)系统峰均功率比(Peak-to-average power ratio, PAPR)的方法,为解决现有ACE算法因选择固定限... 动态星座图扩展(Active constellation extension, ACE)是一种能够有效降低正交频分复用(Orthogonal frequency division multiplexing, OFDM)系统峰均功率比(Peak-to-average power ratio, PAPR)的方法,为解决现有ACE算法因选择固定限幅阈值而限制降低PAPR效果的问题,提出一种最优阈值ACE(Optimal threshold ACE, OTACE)算法,该算法能在每次迭代时根据信号功率求得最合适的限幅阈值,从而增强抑制PAPR的效果.通过数据拟合得到合适的迭代次数,在此基础上对OTACE算法抑制PAPR的效果进行了仿真分析,仿真结果表明,与凸集映射(Projection onto convex sets, POCS)和智能梯度投影(Smart gradient projection, SGP)算法相比,OTACE分别能提高5 dB和3 dB左右的PAPR增益.在广电1、广电6和巴西A三种信道下,分别在多普勒频移为20 Hz和60 Hz时测试OTACE算法对系统误码率(Bit error rate, BER)的影响.实验结果显示,采用OTACE可提高系统的BER性能,并且与POCS相比,OTACE可提高1 dB左右的信噪比(Signal-to-noise ratio,SNR)增益;与SGP相比,OTACE在高SNR时有明显的优势. 展开更多
关键词 正交频分复用 峰均功率比 动态星座图扩展 迭代 阈值
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大陆克拉通早期构造演化历史探讨:以华北为例 被引量:49
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作者 李江海 牛向龙 +1 位作者 程素华 钱祥麟 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 2006年第3期285-293,共9页
大陆早期构造演化的研究一直是大陆地质学研究的焦点问题.在华北克拉通基底构造1∶200万编图研究基础上,本文开展基底断裂边界、构造样式及后期叠加关系的研究,借鉴比较大地构造理论,对华北克拉通基底重新进行了构造区划.结合标志性构... 大陆早期构造演化的研究一直是大陆地质学研究的焦点问题.在华北克拉通基底构造1∶200万编图研究基础上,本文开展基底断裂边界、构造样式及后期叠加关系的研究,借鉴比较大地构造理论,对华北克拉通基底重新进行了构造区划.结合标志性构造单元及其时代、同位素年龄数据库的综合研究,提出华北早期构造格局演化及其重大构造热事件.华北克拉通基底主要由大面积的新太古代TTG杂岩及表壳岩系组成,新太古代涉及活动陆缘环境的大规模陆壳增生及不同微陆块的碰撞聚合过程,造成新太古代末期陆壳迅速增生和克拉通化.古元古代初期开始伸展裂解和早期盖层发育阶段,古元古代晚期发生微陆块碰撞缝合,形成超级克拉通,并在克拉通西北边缘发生强烈改造作用.1.84Ga前后,华北克拉通经历最强烈的一次伸展裂解过程,从超级克拉通裂解,开始了独立的构造演化,在伸展构造背景下,克拉通基底被强烈隆升冷却,经历风化剥蚀,发育沉积盖层.以上构造格局及其构造热事件提供了早期超级大陆再造研究的构造制约条件. 展开更多
关键词 板块构造 构造区划 构造热事件 活动陆缘 伸展作用 超级大陆
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南海西缘断裂带的活动性研究 被引量:8
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作者 孙龙涛 詹文欢 +2 位作者 孙宗勋 朱俊江 赵明辉 《海洋通报》 CAS CSCD 北大核心 2005年第3期42-47,共6页
南海西缘断裂带是一条典型的右旋走滑断裂系统,是南海扩张的西部边界,两端形成具有明显走滑特征的“Y”型和“人”型构造。其前锋端形成走滑-伸展叠瓦扇,尾端形成走滑-收缩叠瓦扇,中部形成走滑-拉分双重构造的右旋走滑系统。其动力主要... 南海西缘断裂带是一条典型的右旋走滑断裂系统,是南海扩张的西部边界,两端形成具有明显走滑特征的“Y”型和“人”型构造。其前锋端形成走滑-伸展叠瓦扇,尾端形成走滑-收缩叠瓦扇,中部形成走滑-拉分双重构造的右旋走滑系统。其动力主要来源于白垩纪以来的印-藏碰撞、新生代印支挤出和南海扩张作用。经历了两期构造运动而形成的该断裂系统对其周边盆地的形成起到了主要控制作用。 展开更多
关键词 活动性 右旋断裂 走滑拉张
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济阳坳陷及鲁西隆起区中、新生代伸展与断裂活动特征 被引量:9
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作者 丁增勇 王良书 +2 位作者 张鹏 钟锴 刘绍文 《石油与天然气地质》 EI CAS CSCD 北大核心 2008年第1期107-112,140,共7页
济阳坳陷与鲁西隆起具有相同类型的结晶基底。选取这两个地区近年来3条有代表性的大跨度深层反射地震剖面,重建盆地沉积岩层埋藏史,通过反复拟合盆地内部构造形态,定量计算各主要构造演化阶段的构造运动学参数,详细解析了基底伸展变形... 济阳坳陷与鲁西隆起具有相同类型的结晶基底。选取这两个地区近年来3条有代表性的大跨度深层反射地震剖面,重建盆地沉积岩层埋藏史,通过反复拟合盆地内部构造形态,定量计算各主要构造演化阶段的构造运动学参数,详细解析了基底伸展变形过程。结果表明济阳坳陷与鲁西隆起区基底伸展及断裂活动在时空上很不均衡,两个地区古近纪伸展变形强度均显著大于中生代;古近纪济阳坳陷南北向地壳伸展率和伸展速率均为东西向的两倍以上。 展开更多
关键词 基底伸展 断裂活动 济阳坳陷 鲁西隆起
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