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PNIPAm温敏纳米纤维膜:交联作用下的形貌稳定性和响应行为
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作者 田晓靖 黄至纯 +3 位作者 张青松 王旭 杨宁 邓南平 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第4期52-67,共16页
聚N-异丙基丙烯酰胺(PNIPAm)交联温敏纳米纤维膜作为一种相变温度易于控制的新兴响应性材料,克服了传统PNIPAm块状水凝胶的生产成本高、响应速率慢和PNIPAm非交联温敏纳米纤维耐水性差的缺点,受到广泛研究并应用于智能开关、温度致动器... 聚N-异丙基丙烯酰胺(PNIPAm)交联温敏纳米纤维膜作为一种相变温度易于控制的新兴响应性材料,克服了传统PNIPAm块状水凝胶的生产成本高、响应速率慢和PNIPAm非交联温敏纳米纤维耐水性差的缺点,受到广泛研究并应用于智能开关、温度致动器、水油分离、药物、细胞控制释放和伤口敷料等领域。形貌稳定性和快速响应性是温敏纳米纤维膜在重复体积变化过程中最大的挑战,同时也作为评价PNIPAm温敏纳米纤维膜的实用性最重要指标引起了人们广泛的关注。本文全面综述了PNIPAm温敏纳米纤维膜近二十年来国内外的突破性进展和非交联作用下PNIPAm温敏纳米纤维膜的形貌变化和响应性,重点综合分析了物理和化学交联中交联反应类型、交联度、交联时间和交联分子量对PNIPAm温敏纳米纤维膜的形貌稳定性和响应行为的影响,为之后纤维膜的交联处理提供了理论支持,并对PNIPAm温敏纳米纤维膜的发展及应用前景进行了展望。 展开更多
关键词 聚N-异丙基丙烯酰胺 纳米纤维膜 形貌稳定性 响应性 耐水性
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鄂尔多斯盆地大牛地气田马五_(6~10)亚段沉积相高频演化特征
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作者 刘兆恒 吴冬 +5 位作者 邓虎成 伏美燕 曹凯旋 胥旺 刘慧 李可赛 《科学技术与工程》 北大核心 2024年第9期3554-3566,共13页
鄂尔多斯盆地大牛地气田马五_(6~10)亚段沉积微相高频变化,分布特征尚不明确,严重制约了天然气勘探与开发。综合利用岩心、薄片、测井及野外露头等资料,详细分析了该地区马五_(6~10)亚段碳酸盐岩岩石类型及测井响应特征,划分了4种沉积微... 鄂尔多斯盆地大牛地气田马五_(6~10)亚段沉积微相高频变化,分布特征尚不明确,严重制约了天然气勘探与开发。综合利用岩心、薄片、测井及野外露头等资料,详细分析了该地区马五_(6~10)亚段碳酸盐岩岩石类型及测井响应特征,划分了4种沉积微相,进一步分析了该地区马五_(6~10)亚段高频沉积相演化特征。研究表明,马五期海平面整体呈下降趋势,发育局限台地亚相,云坪、膏云坪、灰云坪微相在空间上彼此相邻,纵向上相互叠置,随海平面的涨落沉积微相在膏云坪、云坪和云坪、灰云坪、云灰坪之间频繁转化。马五_(10)、马五_(8)、马五_(7)^(2)、马五_(6)^(1)亚段主要发育膏云坪和云坪微相,马五_(9)亚段主要发育云坪和灰云坪微相,马五_(7)^(1)、马五_(6)^(2)亚段主要发育膏云坪、云坪及灰云坪微相,马五_(6)^(3)亚段则由西向东依次发育膏云坪、云坪、灰云坪、云灰坪微相。研究区海平面升降控制了沉积亚相的演化,更为高频的次级海平面变化控制着沉积微相快速变化。鄂尔多斯盆地大牛地气田马五_(6~10)亚段沉积相高频演化特征研究,将有力支撑大牛地气田马家沟组深部天然气资源的开发动用,同时为大牛地气田马家沟组沉积模式研究提供依据。 展开更多
关键词 鄂尔多斯盆地 大牛地气田 碳酸盐岩 马五_(6~10)亚段 沉积微相
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Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite
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作者 xu wang Zhengquan Zhang +5 位作者 Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期71-80,共10页
The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB... The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures. 展开更多
关键词 SCHEELITE BETAINE low temperature synergistic effect dispersion FOAMABILITY
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A Fault-Tolerant Mobility-Aware Caching Method in Edge Computing
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作者 Yong Ma Han Zhao +5 位作者 Kunyin Guo Yunni Xia xu wang Xianhua Niu Dongge Zhu Yumin Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期907-927,共21页
Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be dep... Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be deployed and cached on edge servers to optimize the efficiency of content delivery,ultimately enhancing the quality of the user experience.However,due to the typical placement of edge devices and nodes at the network’s periphery,these components may face various potential fault tolerance challenges,including network instability,device failures,and resource constraints.Considering the dynamic nature ofMEC,making high-quality content caching decisions for real-time mobile applications,especially those sensitive to latency,by effectively utilizing mobility information,continues to be a significant challenge.In response to this challenge,this paper introduces FT-MAACC,a mobility-aware caching solution grounded in multi-agent deep reinforcement learning and equipped with fault tolerance mechanisms.This approach comprehensively integrates content adaptivity algorithms to evaluate the priority of highly user-adaptive cached content.Furthermore,it relies on collaborative caching strategies based onmulti-agent deep reinforcement learningmodels and establishes a fault-tolerancemodel to ensure the system’s reliability,availability,and persistence.Empirical results unequivocally demonstrate that FTMAACC outperforms its peer methods in cache hit rates and transmission latency. 展开更多
关键词 Mobile edge networks MOBILITY fault tolerance cooperative caching multi-agent deep reinforcement learning content prediction
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Real-time arrival picking of rock microfracture signals based on convolutional-recurrent neural network and its engineering application
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作者 Bing-Rui Chen xu wang +2 位作者 Xinhao Zhu Qing wang Houlin Xie 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期761-777,共17页
Accurately picking P-and S-wave arrivals of microseismic(MS)signals in real-time directly influences the early warning of rock mass failure.A common contradiction between accuracy and computation exists in the current... Accurately picking P-and S-wave arrivals of microseismic(MS)signals in real-time directly influences the early warning of rock mass failure.A common contradiction between accuracy and computation exists in the current arrival picking methods.Thus,a real-time arrival picking method of MS signals is constructed based on a convolutional-recurrent neural network(CRNN).This method fully utilizes the advantages of convolutional layers and gated recurrent units(GRU)in extracting short-and long-term features,in order to create a precise and lightweight arrival picking structure.Then,the synthetic signals with field noises are used to evaluate the hyperparameters of the CRNN model and obtain an optimal CRNN model.The actual operation on various devices indicates that compared with the U-Net method,the CRNN method achieves faster arrival picking with less performance consumption.An application of large underground caverns in the Yebatan hydropower station(YBT)project shows that compared with the short-term average/long-term average(STA/LTA),Akaike information criterion(AIC)and U-Net methods,the CRNN method has the highest accuracy within four sampling points,which is 87.44%for P-wave and 91.29%for S-wave,respectively.The sum of mean absolute errors(MAESUM)of the CRNN method is 4.22 sampling points,which is lower than that of the other methods.Among the four methods,the MS sources location calculated based on the CRNN method shows the best consistency with the actual failure,which occurs at the junction of the shaft and the second gallery.Thus,the proposed method can pick up P-and S-arrival accurately and rapidly,providing a reference for rock failure analysis and evaluation in engineering applications. 展开更多
关键词 Rock mass failure Microseismic event P-wave arrival S-wave arrival Deep learning
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Analytical solutions of turbulent boundary layer beneath forward-leaning waves
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作者 Yiqin XIE Jifu ZHOU +3 位作者 xu wang Jinlong DUAN Yongjun LU Shouqian LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期695-710,共16页
As a typical nonlinear wave,forward-leaning waves can be frequently encountered in the near-shore areas,which can impact coastal sediment transport significantly.Hence,it is of significance to describe the characteris... As a typical nonlinear wave,forward-leaning waves can be frequently encountered in the near-shore areas,which can impact coastal sediment transport significantly.Hence,it is of significance to describe the characteristics of the boundary layer beneath forward-leaning waves accurately,especially for the turbulent boundary layer.In this work,the linearized turbulent boundary layer model with a linear turbulent viscosity coefficient is applied,and the novel expression of the near-bed orbital velocity that has been worked out by the authors for forward-leaning waves of arbitrary forward-leaning degrees is further used to specify the free stream boundary condition of the bottom boundary layer.Then,a variable transformation is found so as to make the equation of the turbulent boundary layer model be solved analytically through a modified Bessel function.Consequently,an explicit analytical solution of the turbulent boundary layer beneath forward-leaning waves is derived by means of variable separation and variable transformation.The analytical solutions of the velocity profile and bottom shear stress of the turbulent boundary layer beneath forward-leaning waves are verified by comparing the present analytical results with typical experimental data available in the previous literature. 展开更多
关键词 forward-leaning wave turbulent boundary layer velocity profile bottom shear stress
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Numerical study on the cavity dynamics for vertical water entries of twin spheres
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作者 xu wang xujian Lyu +1 位作者 Ruisheng Sun Dongdong Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期459-472,共14页
In this study, a three dimensional(3D) numerical model of six-degrees-of-freedom(6DOF) is applied to simulate the water entries of twin spheres side-by-side at different lateral distances and time intervals.The turbul... In this study, a three dimensional(3D) numerical model of six-degrees-of-freedom(6DOF) is applied to simulate the water entries of twin spheres side-by-side at different lateral distances and time intervals.The turbulence structure is described using the shear-stress transport k-ω(SST k-ω) model, and the volume of fluid(VOF) method is used to track the complex air-liquid interface. The motion of spheres during water entry is simulated using an independent overset grid. The numerical model is verified by comparing the cavity evolution results from simulations and experiments. Numerical results reveal that the time interval between the twin water entries evidently affects cavity expansion and contraction behaviors in the radial direction. However, this influence is significantly weakened by increasing the lateral distance between the two spheres. In synchronous water entries, pressure is reduced on the midline of two cavities during surface closure, which is directly related to the cavity volume. The evolution of vortexes inside the two cavities is analyzed using a velocity vector field, which is affected by the lateral distance and time interval of water entries. 展开更多
关键词 Twin water entries Side-by-side CAVITY Numerical simulation
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Alkaline sphingomyelinase deficiency impairs intestinal mucosal barrier integrity and reduces antioxidant capacity in dextran sulfate sodium-induced colitis
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作者 Ye Tian Xin Li +7 位作者 xu wang Si-Ting Pei Hong-Xin Pan Yu-Qi Cheng Yi-Chen Li Wen-Ting Cao Jin-Dong Ding Petersen Ping Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1405-1419,共15页
BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported ... BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway. 展开更多
关键词 Alkaline sphingomyelinase Intestinal mucosal barrier Antioxidant capacity Dextran sulfate sodium-induced colitis nuclear factor erythroid 2-related factor 2
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Pulse rate estimation based on facial videos:an evaluation and optimization of the classical methods using both self-constructed and public datasets
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作者 Chao-Yong Wu Jian-Xin Chen +3 位作者 Yu Chen Ai-Ping Chen Lu Zhou xu wang 《Traditional Medicine Research》 2024年第1期14-22,共9页
Pulse rate is one of the important characteristics of traditional Chinese medicine pulse diagnosis,and it is of great significance for determining the nature of cold and heat in diseases.The prediction of pulse rate b... Pulse rate is one of the important characteristics of traditional Chinese medicine pulse diagnosis,and it is of great significance for determining the nature of cold and heat in diseases.The prediction of pulse rate based on facial video is an exciting research field for getting palpation information by observation diagnosis.However,most studies focus on optimizing the algorithm based on a small sample of participants without systematically investigating multiple influencing factors.A total of 209 participants and 2,435 facial videos,based on our self-constructed Multi-Scene Sign Dataset and the public datasets,were used to perform a multi-level and multi-factor comprehensive comparison.The effects of different datasets,blood volume pulse signal extraction algorithms,region of interests,time windows,color spaces,pulse rate calculation methods,and video recording scenes were analyzed.Furthermore,we proposed a blood volume pulse signal quality optimization strategy based on the inverse Fourier transform and an improvement strategy for pulse rate estimation based on signal-to-noise ratio threshold sliding.We found that the effects of video estimation of pulse rate in the Multi-Scene Sign Dataset and Pulse Rate Detection Dataset were better than in other datasets.Compared with Fast independent component analysis and Single Channel algorithms,chrominance-based method and plane-orthogonal-to-skin algorithms have a more vital anti-interference ability and higher robustness.The performances of the five-organs fusion area and the full-face area were better than that of single sub-regions,and the fewer motion artifacts and better lighting can improve the precision of pulse rate estimation. 展开更多
关键词 pulse rate heart rate PHOTOPLETHYSMOGRAPHY observation and pulse diagnosis facial videos
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Expression of PDGFR-α in Patients with Valvular Atrial Fibrillation
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作者 Mengxia Su xu wang +3 位作者 Rui Zhao Yulu Yang Feng Ma Junqiang Pan 《International Journal of Clinical Medicine》 2023年第6期291-301,共11页
Objective: To investigate the expression of Platelet-derived growth factor receptor alpha (PDGFR-α) in patients who have valvular atrial fibrillation. Methods: In this research, eighty-four patients with rheumatic he... Objective: To investigate the expression of Platelet-derived growth factor receptor alpha (PDGFR-α) in patients who have valvular atrial fibrillation. Methods: In this research, eighty-four patients with rheumatic heart disease who were going to undertake cardiac surgery were included. The subjects were divided into two groups: the AF group and the sinus rhythm group, the quantities are 39 and 45 respectively. Before the surgery, baseline demographics, physical examination, routine laboratory testing, echocardiography, echocardiographic data and additional clinical data were available for all patients. The right atrial tissue of the subjects was separated during surgery, with an area of approximately 0.3 - 0.5 mm<sup>3</sup>. Immunofluorescence staining was used to analyze the distribution of PDGFR-α of atrial tissue. mRNA of PDGFR-α in atrial tissue were determined by real-time quantitative PCR (Polymerase Chain Reaction);Western-Blot technique was used to measure the protein of PDGFR-α in atrial tissue. Results: There were no significant differences (P > 0.05) in sex ratio, age, blood pressure, blood biochemistry, and other aspects of medical history between the two groups. However, the right and left atrium diameters in the AF group were markedly larger than those in the SR group (P α from right atrial tissue were obviously higher in the AF group than that in the SR group (P Conclusion: The expression of PDGFR-α in the right atrial tissue of patients with atrial fibrillation was found to be significantly higher. 展开更多
关键词 Rheumatic Heart Disease Atrial Fibrillation Atrial Remodeling Platelet-Derived Growth Factor Receptor-α CARDIOLOGY
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大运河文化带生态美学与社会美育价值研究 被引量:1
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作者 徐望 《城市规划》 CSCD 北大核心 2023年第8期57-65,共9页
大运河文化带不仅具有历史文化和社会经济价值,也具有美学与美育价值。可以从生态美学的实践根基、本体论、存在论3个理论维度分析大运河文化带的建设。所有人都生存于一定的生态环境之中,基于生态美学,塑造生态环境之美,是重要的社会... 大运河文化带不仅具有历史文化和社会经济价值,也具有美学与美育价值。可以从生态美学的实践根基、本体论、存在论3个理论维度分析大运河文化带的建设。所有人都生存于一定的生态环境之中,基于生态美学,塑造生态环境之美,是重要的社会美育途径。大运河文化带发挥社会美育价值的三大途径是:通过构筑生态景观进行生态美育;通过发展文旅融合进行人文美育;通过创作公共艺术进行艺术美育。提升大运河文化带生态美学与社会美育价值的策略有:“文化为魂”凸显“运河之美”的历史底蕴与时代价值;营造“诗意生存”生态,推动“诗意运河”建设;优化文化艺术供给,促进社会美育供给。 展开更多
关键词 大运河文化带 生态美学 社会美育 文旅融合 公共文化 建设规划
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头皮机械刺激通过控制脑水肿减轻2-VO大鼠脑低灌注
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作者 谭琰 张华伟 +7 位作者 张策 陈伟航 彭甜甜 刘肇恒 王旭 张平 Jin Louis Lei 华茜 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第4期440-447,523,共9页
目的:探讨头皮机械刺激(SMS),作用机理与头针相似,对脑低灌注大鼠脑水肿的脑保护作用。方法:首先,我们通过测量皮肤温度和脑血流量来筛选SMS的强度。接下来,我们观察了头皮机械刺激对2-VO模型大鼠脑血流量、脑水肿和相关病理学改变的脑... 目的:探讨头皮机械刺激(SMS),作用机理与头针相似,对脑低灌注大鼠脑水肿的脑保护作用。方法:首先,我们通过测量皮肤温度和脑血流量来筛选SMS的强度。接下来,我们观察了头皮机械刺激对2-VO模型大鼠脑血流量、脑水肿和相关病理学改变的脑保护作用。利用免疫组化和免疫印迹法检测神经凋亡相关蛋白(caspase-3、cleaved-caspase-3)和脑水肿相关蛋白(GFAP和AQP4)的表达差异。随后分析神经细胞凋亡与AQP4蛋白水平的相关性。结果:0.5 N为最适合本研究的刺激强度。与对照组相比,0.5 N、1 N、2 N组均可以维持头皮温度,改善脑血流量(均P<0.05)。SMS干预显著增加了2-VO大鼠脑血流量,降低脑含水量(P<0.001和P=0.0449)。与2-VO组相比,SMS组大鼠海马CA1区caspase-3阳性细胞数(P=0.0086)和cleavedcaspase-3阳性细胞数(P=0.036)显著减少,与caspase-3蛋白表达水平(P=0.019)相似。与sham组比较,2-VO组大鼠GFAP和AQP4表达增高(P=0.0369和P=0.0142),SMS组大鼠GFAP和AQP4表达明显降低(P=0.0484和P=0.0229)。AQP4与caspase-3、cleavedcaspase-3的表达呈正相关(R2=0.6071/R2=0.8500)。结论:本研究揭示了SMS改善脑低灌注的最佳强度及其可能的作用机制。SMS可能是一种简便、有前景的预防缺血性卒中和认知障碍的方法。 展开更多
关键词 头皮机械刺激 脑低灌注 星形胶质细胞 水通道蛋白4 细胞凋亡
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The efficacy of Xuefu Zhuyu prescription for diabetic encephalopathy: A meta-analysis of randomized controlled trials
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作者 Yin-Li Shi xu wang 《Journal of Hainan Medical University》 2021年第5期38-43,共6页
Objective:To evaluate the safety and effectiveness of Xuefu Zhuyu Decoction in treating diabetic encephalopathy.Methods:Computer search and manual search of Pub Med,Web of Science,The Cochrane Library,CNKI,WF,VIP and ... Objective:To evaluate the safety and effectiveness of Xuefu Zhuyu Decoction in treating diabetic encephalopathy.Methods:Computer search and manual search of Pub Med,Web of Science,The Cochrane Library,CNKI,WF,VIP and CBM from January 2000 to April 2020 on the treatment of diabetic encephalopathy with Xuefu Zhuyu Decoction In randomized controlled clinical trials,select documents that meet the criteria for analysis using Rev Man 5.3 software.Results:A total of 11 articles and 838 patients were included in the study.Metaanalysis showed that Xuefu Zhuyu Decoction was effective(OR=3.71,95%CI[2.42,5.70],P<0.00001),and the patient’s neurological deficit score(MD=-4.52,95%CI[-5.10,-3.94],P<0.00001),fasting blood glucose(MD=-1.05,95%CI[-1.51,-0.59],P<0.00001),2 hours postprandial blood glucose(MD=-1.31,95%CI[-1.94,-0.69],P<0.00001),glycated hemoglobin(MD=-0.94,95%CI[-1.15,-0.72],P<0.00001),TCM symptom score(MD=-2.44,95%CI[-3.82,-1.06],P=0.0005<0.01),vitality score(MD=12.79,95%CI[8.79,16.79],P<0.00001),the improvement effect is obvious Better than conventional Western medicine treatment.Conclusion:Xuefu Zhuyu Decoction can improve the clinical efficiency of patients with diabetic encephalopathy,reduce brain damage,reduce blood sugar and glycated hemoglobin levels,and has good safety.However,the quality of some of the included literatures is low,and the number of clinical cases is small,which may affect the authenticity of the Meta analysis results.Still need to be further verified by clinical randomized controlled trials with high-quality large samples. 展开更多
关键词 Xuefu Zhuyu decoction DIABETES ENCEPHALOPATHY Traditional Chinese medicine treatment Meta analysis
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中国居民文化消费的时间困境与解困之策
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作者 徐望 《河南教育学院学报(哲学社会科学版)》 2023年第5期10-16,共7页
文化消费是时间密集型消费,中国居民现实中所拥有的休闲时间与文化消费的发展休戚相关。当前,中国居民普遍缺乏休闲时间,在文化消费上陷入了时间困境。要突破这一困境,充分释放文化消费潜力,既要保障人民休闲时间、发展社会生活服务、... 文化消费是时间密集型消费,中国居民现实中所拥有的休闲时间与文化消费的发展休戚相关。当前,中国居民普遍缺乏休闲时间,在文化消费上陷入了时间困境。要突破这一困境,充分释放文化消费潜力,既要保障人民休闲时间、发展社会生活服务、培育社会休闲风尚,又要传承中华传统休闲文化和休闲美学,发展品质化、审美化休闲,提升人民休闲素养。 展开更多
关键词 文化消费 文化休闲 休闲时间 时间困境 休息休假
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基于MRE的变刚度变阻尼减振器设计研究 被引量:10
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作者 毕凤荣 曹荣康 +1 位作者 xu wang 马腾 《振动与冲击》 EI CSCD 北大核心 2019年第3期192-198,共7页
针对磁流变弹性体材料的变刚度及变阻尼特性,将其成功应用于半主动控制减振器研究中。设计专用磁场发生夹具,制备了具有良好磁流变效应的磁流变弹性体材料,并对其力学性能参数进行测试;根据磁流变弹性体材料在挤压工作模式和剪切工作模... 针对磁流变弹性体材料的变刚度及变阻尼特性,将其成功应用于半主动控制减振器研究中。设计专用磁场发生夹具,制备了具有良好磁流变效应的磁流变弹性体材料,并对其力学性能参数进行测试;根据磁流变弹性体材料在挤压工作模式和剪切工作模式的特性,设计了刚度、阻尼均可变化的减振器,并利用有限元软件对该设计方案进行电磁场仿真分析;试制减振器原理样机,在INSTRON万能拉压试验机上,测试其在不同磁感应强度下的变刚度变阻尼特性。试验结果表明:在模拟半主动控制策略下其动刚度变化最大可达55.4%,阻尼变化可达214.3%,证明了该设计方案的可行性。 展开更多
关键词 磁流变弹性体 减振器 变阻尼 变刚度 半主动控制
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Wilhelmy吊片法测定磷脂溶液的表面张力等温线 被引量:1
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作者 李远非 杨训方 +5 位作者 王桂玲 郭莹 王煦 李馨儒 周艳霞 谢英 《大学化学》 CAS 2023年第1期155-160,共6页
表面活性物质的表面张力等温线测定是大学物理化学实验的重要内容。随着磷脂类表面活性剂的广泛应用,有必要在大学化学中更新经典表面张力等温线测定的实验内容,并使学生掌握先进的测量方法。以二硬脂酰基磷脂酰胆碱(DSPC)和二棕榈酰基... 表面活性物质的表面张力等温线测定是大学物理化学实验的重要内容。随着磷脂类表面活性剂的广泛应用,有必要在大学化学中更新经典表面张力等温线测定的实验内容,并使学生掌握先进的测量方法。以二硬脂酰基磷脂酰胆碱(DSPC)和二棕榈酰基磷脂酰胆碱(DPPC)为研究对象,应用界面张力仪测定了两种溶液表面张力等温线,计算了其表面超量和分子横截面积,并设计了拓展性实验内容,对于培养学生分析问题和解决问题的能力具有积极的意义。 展开更多
关键词 磷脂 表面张力等温线 实验教学
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The complete reference genome for grapevine (Vitis vinifera L.) genetics and breeding 被引量:8
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作者 Xiaoya Shi Shuo Cao +29 位作者 xu wang Siyang Huang Yue wang Zhongjie Liu Wenwen Liu Xiangpeng Leng Yanling Peng Nan wang Yiwen wang Zhiyao Ma Xiaodong xu Fan Zhang Hui xue Haixia Zhong Yi wang Kekun Zhang Amandine Velt Komlan Avia Daniela Holtgräwe Jérôme Grimplet JoséTomás Matus Doreen Ware Xinyu Wu Haibo wang Chonghuai Liu Yuling Fang Camille Rustenholz Zongming Cheng Hua Xiao Yongfeng Zhou 《Horticulture Research》 SCIE CSCD 2023年第5期207-219,共13页
Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,li... Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs. 展开更多
关键词 BREEDING CROPS CULTIVAR
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Telomere-to-telomere and gap-free reference genome assembly of the kiwifruit Actinidia chinensis 被引量:8
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作者 Junyang Yue Qinyao Chen +14 位作者 Yingzhen wang Lei Zhang Chen Ye xu wang Shuo Cao Yunzhi Lin Wei Huang He Xian Hongyan Qin Yanli wang Sijia Zhang Ying Wu Songhu wang Yi Yue Yongsheng Liu 《Horticulture Research》 SCIE CSCD 2023年第2期134-146,共13页
Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regi... Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regions.Here,we report a highly continuous and completely gap-free reference genome of Actinidia chinensis cv.‘Hongyang’,named Hongyang v4.0,which is the first to achieve two de novo haploid-resolved haplotypes,HY4P and HY4A.HY4P and HY4A have a total length of 606.1 and 599.6 Mb,respectively,with almost the entire telomeres and centromeres assembled in each haplotype.In comparison with Hongyang v3.0,the integrity and contiguity of Hongyang v4.0 is markedly improved by filling all unclosed gaps and correcting some misoriented regions,resulting in∼38.6–39.5 Mb extra sequences,which might affect 4263 and 4244 protein-coding genes in HY4P and HY4A,respectively.Furthermore,our gap-free genome assembly provides the first clue for inspecting the structure and function of centromeres.Globally,centromeric regions are characterized by higher-order repeats that mainly consist of a 153-bp conserved centromere-specific monomer(Ach-CEN153)with different copy numbers among chromosomes.Functional enrichment analysis of the genes located within centromeric regions demonstrates that chromosome centromeres may not only play physical roles for linking a pair of sister chromatids,but also have genetic features for participation in the regulation of cell division.The availability of the telomere-to-telomere and gap-free Hongyang v4.0 reference genome lays a solid foundation not only for illustrating genome structure and functional genomics studies but also for facilitating kiwifruit breeding and improvement. 展开更多
关键词 BREEDING LINKING ASSEMBLY
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基于岩相和地球化学特征的沉积古地貌恢复新方法:以川中栖霞组为例
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作者 饶诗怡 伏美燕 +4 位作者 邓虎成 吴冬 胥旺 陈培 郭恒玮 《地质科技通报》 CAS CSCD 北大核心 2023年第5期205-213,共9页
四川盆地二叠系栖霞组沉积古地貌对碳酸盐岩储层的展布和演化具有一定的控制作用。恢复并刻画川中高石梯地区沉积古地貌,可以进一步认识该区域有利沉积相展布规律、预测优质储层的分布。在明确了三级层序划分的基础上,利用地球化学元素... 四川盆地二叠系栖霞组沉积古地貌对碳酸盐岩储层的展布和演化具有一定的控制作用。恢复并刻画川中高石梯地区沉积古地貌,可以进一步认识该区域有利沉积相展布规律、预测优质储层的分布。在明确了三级层序划分的基础上,利用地球化学元素比值、岩石学标志和测井标志在层序内建立了高分辨率层序地层格架,识别出两种沉积微相:滩核和滩翼;计算了层序内地层厚度差异,识别出不同类型的沉积序列,计算了滩核/滩翼厚度比值以及Fe/Mn比值、MgO/Al_(2)O_(3)比值等地球化学参数。分析上述参数在平面上的特征并进行叠合,恢复了研究区栖霞组沉积时期的古地貌特征。研究结果表明:栖一段古地貌在西北部和南部较高,在中部较低,古地貌落差明显;栖二段古地貌高地分布在研究区中部,西部古地貌较低,古地貌整体差异不大。根据古地貌恢复结果,高石梯-磨溪地区在北东—南西方向形成浅水环带区,发育颗粒滩,南部发育局部微正向构造,同样发育颗粒滩,但微正向构造分布有限,颗粒滩延伸范围因此受限,未来勘探开发应围绕北东—南西方向的颗粒滩发育区域进行。 展开更多
关键词 沉积古地貌 栖霞组 沉积序列 岩相 地球化学
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quarTeT: a telomere-to-telomere toolkit for gap-free genome assembly and centromeric repeat identification 被引量:2
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作者 Yunzhi Lin Chen Ye +12 位作者 Xingzhu Li Qinyao Chen Ying Wu Feng Zhang Rui Pan Sijia Zhang Shuxia Chen xu wang Shuo Cao Yingzhen wang Yi Yue Yongsheng Liu Junyang Yue 《Horticulture Research》 SCIE CSCD 2023年第8期122-128,共7页
A high-quality genome is the basis for studies on functional,evolutionary,and comparative genomics.The majority of attention has been paid to the solution of complex chromosome structures and highly repetitive sequenc... A high-quality genome is the basis for studies on functional,evolutionary,and comparative genomics.The majority of attention has been paid to the solution of complex chromosome structures and highly repetitive sequences,along with the emergence of a new‘telomere-to-telomere(T2T)assembly’era.However,the bioinformatic tools for the automatic construction and/or characterization of T2T genome are limited.Here,we developed a user-friendly web toolkit,quarTeT,which currently includes four modules:AssemblyMapper,GapFiller,TeloExplorer,and CentroMiner.First,AssemblyMapper is designed to assemble phased contigs into the chromosome-level genome by referring to a closely related genome.Then,GapFiller would endeavor to fill all unclosed gaps in a given genome with the aid of additional ultra-long sequences.Finally,TeloExplorer and CentroMiner are applied to identify candidate telomere and centromere as well as their localizations on each chromosome.These four modules can be used alone or in combination with each other for T2T genome assembly and characterization.As a case study,by adopting the entire modular functions of quarTeT,we have achieved the Actinidia chinensis genome assembly that is of a quality comparable to the reported genome Hongyang v4.0,which was assembled with the addition of manual handling.Further evaluation of CentroMiner by searching centromeres in Arabidopsis thaliana and Oryza sativa genomes showed that quarTeT is capable of identifying all the centromeric regions that have been previously detected by experimental methods.Collectively,quarTeT is an efficient toolkit for studies of large-scale T2T genomes and can be accessed at http://www.atcgn.com:8080/quarTeT/home.html without registration. 展开更多
关键词 SEARCHING assembly ALONE
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