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Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections
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作者 Shanshan Su Hongwu Liu +7 位作者 Junrong Zhang Puying Qi Yue Ding Ling Zhang Linli Yang Liwei Liu xiang zhou Song Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1259-1273,共15页
Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a... Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac),and Pseudomonas syringae pv.actinidiae(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),respectively.Meanwhile,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo cells.Taken together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides. 展开更多
关键词 tetrahydro-β-carboline derivatives antibacterial activity ROS cell apoptosis
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An Experimental Study on the Effect of a Nanofluid on Oil-Water Relative Permeability
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作者 Hui Tian Dandan Zhao +3 位作者 Yannan Wu Xingyu Yi Jun Ma xiang zhou 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1265-1277,共13页
The low porosity and low permeability of tight oil reservoirs call for improvements in the current technologies for oil recovery.Traditional chemical solutions with large molecular size cannot effectively flow through... The low porosity and low permeability of tight oil reservoirs call for improvements in the current technologies for oil recovery.Traditional chemical solutions with large molecular size cannot effectively flow through the nanopores of the reservoir.In this study,the feasibility of Nanofluids has been investigated using a high pressure high temperature core-holder and nuclear magnetic resonance(NMR).The results of the experiments indicate that the specified Nanofluids can enhance the tight oil recovery significantly.The water and oil relative permeability curve shifts to the high water saturation side after Nanofluid flooding,thereby demonstrating an increase in the water wettability of the core.In the Nanofluid flooding process the oil recovery was enhanced by 15.1%,compared to waterflooding stage.The T2 spectra using the NMR show that after Nanofluid flooding,a 7.18%increment in oil recovery factor was gained in the small pores,a 4.9%increase in the middle pores,and a 0.29%increase in the large pores.These results confirm that the Nanofluids can improve the flow state in micro-sized pores inside the core and increase the ultimate oil recovery factor. 展开更多
关键词 Tight oil reservoir NANOFLUID relative permeability nuclear magnetic resonance T2 spectrum
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Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?
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作者 Qiao-hang ZHAO Yu-wei SONG +8 位作者 Jian CHEN xiang zhou Ji-lai XIE Qiu-ping YAO Qi-yin DONG Chun FENG Li-ming zhou Wei-ping FU Min JIN 《Current Medical Science》 SCIE CAS 2024年第1期212-222,共11页
Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of Se... Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy outcomes.Methods Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis.According to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy outcomes.Results GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/MQ-DBT.Similarly,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT.Conclusion SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups.Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or DBT.Embryo quality plays a more important role in pregnancy outcomes for RIF patients. 展开更多
关键词 recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies
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Miniaturized power detection module operating in millimeter wave band
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作者 xiang zhou Zhi-Yong Zhong 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期69-76,共8页
The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective ... The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites. 展开更多
关键词 DIODE MINIATURIZATION Power detection Temperature compensation
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Mediating role of social support in dysphoria,despondency,and quality of life in patients undergoing maintenance hemodialysis
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作者 xiang zhou Hong Jiang +4 位作者 Yi-Peng zhou Xiao-Yu Wang Hai-Yan Ren Xue-Fei Tian Qing-Qing Zhang 《World Journal of Psychiatry》 SCIE 2024年第3期409-420,共12页
BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can signif... BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD.Currently,there is limited research on how social support mediates the relationship between dysphoria,despondency,and overall QOL in patients undergoing MHD.It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD,ultimately enhancing their overall QOL.AIM To investigate the mediating role of social support in relationships between dysphoria,despondency,and QOL among patients undergoing MHD.METHODS Participants comprised 289 patients undergoing MHD,who were selected using a random sampling approach.The Social Support Rating Scale,Self-Rating Anxiety Scale,Self-Rating Depression Scale,and QOL Scale were administered.Correlation analysis was performed to examine the associations between social support,dysphoria,despondency,and QOL in patients undergoing MHD.To assess the mediating impact of social support on dysphoria,despondency,and QOL in patients undergoing MHD,a bootstrap method was applied.RESULTS Significant correlations among social support,dysphoria,despondency,and quality in patients undergoing MHD were observed(all P<0.01).Dysphoria and despondency negatively correlated with social support and QOL(P<0.01).Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD(P<0.05).The direct effect of dysphoria on QOL was statistically significant(P<0.05).Social support mediated the relationship between dysphoria and QOL,and this mediating effect was significant(P<0.05).Similarly,the direct effect of despondency on QOL was significant(P<0.05).Moreover,social support played a mediating role between despondency and QOL,with a significant mediating effect(P<0.05).CONCLUSION These findings suggest that social support plays a significant mediating role in the relationship between dysphoria,despondency,and QOL in patients undergoing MHD. 展开更多
关键词 Maintenance hemodialysis Social support DYSPHORIA Despondency Quality of life Mediating effect
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Microseismic monitoring and forecasting of dynamic disasters in underground hydropower projects in southwest China:A review 被引量:4
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作者 Biao Li Nuwen Xu +4 位作者 Peiwei Xiao Yong Xia xiang zhou Gongkai Gu Xingguo Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第8期2158-2177,共20页
The underground hydropower projects in Southwest China is characterized by large excavation sizes,high geostresses,complicated geological conditions and multiple construction processes.Various disasters such as collap... The underground hydropower projects in Southwest China is characterized by large excavation sizes,high geostresses,complicated geological conditions and multiple construction processes.Various disasters such as collapses,large deformations,rockbursts are frequently encountered,resulting in serious casualties and huge economic losses.This review mainly presents some representative results on microseismic(MS)monitoring and forecasting for disasters in hydropower underground engineering.First,a set of new denoising,spectral analysis,and location methods were developed for better identification and location of MS signals.Then,the tempo-spatial characteristics of MS events were analyzed to understand the relationship between field construction and damages of surrounding rocks.Combined with field construction,geological data,numerical simulation and parametric analysis of MS sources,the focal mechanism of MS events was revealed.A damage constitutive model considering MS fracturing size was put forward and feedback analysis considering the MS damage of underground surrounding rocks was conducted.Next,an MS multi-parameter based risk assessment and early warning method for dynamic disasters were proposed.The technology for control of the damage and deformation of underground surrounding rocks was proposed for underground caverns.Finally,two typical underground powerhouses were selected as case studies.These achievements can provide significant references for prevention and control of dynamic disasters for underground engineering with similar complicated geological conditions. 展开更多
关键词 MS monitoring Forecasting method Control technology Dynamic disaster Underground engineering
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Estimation of surface water content at the Tianwen-1 Zhurong landing site 被引量:1
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作者 xiang zhou Yang Liu +2 位作者 Xing Wu ZhenXing Zhao YongLiao Zou 《Earth and Planetary Physics》 EI CSCD 2023年第3期347-355,共9页
China’s first Mars rover,Zhurong,successfully landed in the south of Utopia Planitia.The surface water content at the landing area can provide constraints on mineral formation conditions and help us better understand... China’s first Mars rover,Zhurong,successfully landed in the south of Utopia Planitia.The surface water content at the landing area can provide constraints on mineral formation conditions and help us better understand the evolution of the Martian aqueous and geological environment.In this work,the surface kinetic temperature of the Zhurong landing area was derived by analyzing data from the Mars Express Observatoire pour la Minéralogie,l’Eau,les Glaces et l’Activité(OMEGA)spectrometer.Using the Discrete Ordinate Radiative Transfer(DISORT)model,we performed atmospheric correction and thermal correction for the OMEGA data to obtain the surface effective single-particle absorption thickness(ESPAT)parameter to evaluate the surface water content.The surface water content distribution at the landing area was relatively uniform at a lateral scale of~10 km.At the Zhurong landing site,the surface water content in the topmost layer(a few hundred micrometers)of the regolith was 5−8 weight percent water(wt%H_(2)O),assuming surface particle sizes of<45μm,or 1.6−2.5 wt%H_(2)O,assuming surface particle sizes in the range of 125−250μm.The Mars Surface Composition Detector(MarSCoDe)onboard Zhurong also observed significant H_(2)O/OH signals in the landing area.Our results provide an important regional context for the hydration state of the area and can be further verified by the H content derived from the Laser-Induced Breakdown Spectrometer(LIBS)data of MarSCoDe. 展开更多
关键词 MARS Zhurong surface water content Observatoire pour la Minéralogie l’Eau les Glaces et l’Activité(OMEGA) Discrete Ordinate Radiative Transfer(DISORT)
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蒸压陶粒轻骨料混凝土的力学性能研究
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作者 王冬云 崔崇 +1 位作者 项洲 孙宇航 《黄冈师范学院学报》 2023年第6期43-46,共4页
为探究蒸压陶粒轻骨料混凝土中的力学性能,研究了蒸压陶粒轻骨料混凝土在不同水灰比条件下的干表观密度、抗压强度、劈裂抗拉强度和超声波声速。结果发现:蒸压陶粒轻骨料陶粒混凝土的干表观密度为1855~1988kg/m^(3)之间,蒸压陶粒轻骨料... 为探究蒸压陶粒轻骨料混凝土中的力学性能,研究了蒸压陶粒轻骨料混凝土在不同水灰比条件下的干表观密度、抗压强度、劈裂抗拉强度和超声波声速。结果发现:蒸压陶粒轻骨料陶粒混凝土的干表观密度为1855~1988kg/m^(3)之间,蒸压陶粒轻骨料混凝土在1d、3d和7d的强度分别是28d强度的37%~66%、73%~76%和84%~92%。劈裂抗拉强度满足结构混凝土的要求。陶粒混凝土1d、3d和7d的抗压强度与28d强度具有良好的线性关系,28d劈裂抗拉强度与28d抗压强度有良好的指数关系,陶粒混凝土的强度与超声波声速存在较强的指数关系。该研究成果将为蒸压陶粒在混凝土中的应用提供技术支撑。 展开更多
关键词 陶粒混凝土 抗压强度 劈裂抗拉强度 超声波声速
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Factors controlling the formation and evolution of source rocks in the Shahezi Formation,Xujiaweizi fault depression,Songliao Basin 被引量:1
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作者 xiang zhou Lidong Sun 《Energy Geoscience》 2023年第2期1-16,共16页
The types and quality of source rocks in the Shahezi Formation are the key factors affecting the distributions of various deep gas reservoirs in the Xujiaweizi fault depression in Songliao Basin.To clarify the quality... The types and quality of source rocks in the Shahezi Formation are the key factors affecting the distributions of various deep gas reservoirs in the Xujiaweizi fault depression in Songliao Basin.To clarify the quality differences and origins of different types of source rocks in the Shahezi Formation,this study reconstructed the sedimentary and water environment,determined the controlling effects of fault activity,sedimentary facies,and paleo-sedimentary environment on the quality of various source rocks,by making full use of seismic,logging,core,organic geochemical and element geochemical analysis.The results show that two types of source rocks developed in the Shahezi Formation,namely,mudstones and coals.The mudstones have a relatively high abundance of organic matter,which consists of type-Ⅱ kerogen and partial type-Ⅲ kerogen,and are concentrated in Sha-I Member.The coals have a high abundance of organic matter,which consist of type-Ⅲ kerogen,and are mainly distributed in Sha-Ⅱ Member.During the deposition of Sha-I Member,intense fault activity formed arrow,deep-water lacustrine basins with high salinity and strong reducibility on the downthrow sides of faults.During the deposition of Sha-II Member,fault activity progressively weakened,and the areas of lacustrine basins enlarged to their maximum values and became wide,shallow-water basins with low salinity and low reducibility.The development of source rocks was controlled by fault activity,sedimentary facies,and paleo-sedimentary environment.Fault activity formed accommodation space on the downthrown sides of faults for mudstone accumulation,thus determining mudstone thickness.The sedimentary environment controlled the organic matter input and determined the distribution of mudstones and coals.The paleo-sedimentary environment,which consisted of paleo-salinity,as well as paleo-water depth and redox conditions,affected the accumulation and preservation of organic matter and is the main controlling factor for the quality difference of various source rocks in the Shahezi Formation. 展开更多
关键词 FAULT Paleo-environment evolution Source rock Deep gas reservoirs Shahezi Formation Xujiaweizi fault depression
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Visualization and early warning analysis of damage degree of surrounding rock mass in underground powerhouse
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作者 Yuepeng Sun Haijian Su +5 位作者 Peiwei Xiao Peng Li Biao Li xiang zhou Kaiqi Bian Nuwen Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第6期717-731,共15页
Based on the underground powerhouse of Shuangjiangkou hydropower station,Octree theory is adopted to define the indices of the microseismic(MS)spatial aggregation degree and the deviation values of MS count and energy... Based on the underground powerhouse of Shuangjiangkou hydropower station,Octree theory is adopted to define the indices of the microseismic(MS)spatial aggregation degree and the deviation values of MS count and energy.The relationship between the MS multiple parameters and surrounding rock mass instability is established from three aspects:time,space,and strength.Supplemented by the center frequency of the signal evolution characteristics,A fuzzy comprehensive evaluation model and the evolution trend of the MS event center frequency are constructed to quantitatively describe the early warning state of the surrounding rock mass instability.The results show that the multilevel tree structure and voxels generated based on the Octree theory fit relatively well with the set of MS points in threedimensional space.The fuzzy comprehensive evaluation model based on MS spatial aggregation and MS count and energy deviation values enables three-dimensional visualization of the potential damage area and damage extent of the surrounding rock mass.The warning time and potential damage zone quantified are highly consistent with the characteristics of MS precursors,with wide recognition and field investigation results,which fully validate the rationality and applicability of the proposed method.These findings can provide references for the early warning of surrounding rock mass instability in similar underground engineering. 展开更多
关键词 Underground powerhouse MS monitoring Early warning VISUALIZATION
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一种深度卷积自编码网络及其在滚动轴承故障诊断中的应用 被引量:49
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作者 张西宁 向宙 唐春华 《西安交通大学学报》 EI CAS CSCD 北大核心 2018年第7期1-8,59,共9页
为了解决卷积神经网络权值往往只能随机初始化的问题,提出了一种卷积自编码器。以卷积池化过后的特征为权值,对反卷积核进行叠加,叠加步长为池化时的长度,将信号重构回原信号空间。以原信号与重构信号的差值最小为目标,对卷积核和反卷... 为了解决卷积神经网络权值往往只能随机初始化的问题,提出了一种卷积自编码器。以卷积池化过后的特征为权值,对反卷积核进行叠加,叠加步长为池化时的长度,将信号重构回原信号空间。以原信号与重构信号的差值最小为目标,对卷积核和反卷积核进行优化。进一步,编码特征可以作为新的输入,利用同样的方式进行编码,依次循环,最后给网络加上全连接网络和分类器,用少量带标签样本进行微调,形成具有复杂特征提取能力的深度卷积自编码网络。将该网络用于滚动轴承故障识别,将时域振动信号直接输入网络,在公共数据集——西储大学轴承数据集以及实验室实测数据集上均取得了比传统卷积神经网络要好得多的识别效果,例如在实验室实测数据集上将识别精度从0.799提高到了0.921。将底层提取到的特征通过反卷积核逐层重构,第一次在原信号空间看到了神经网络到底"学"到了什么。观察重构信号可知,卷积神经网络对信号特征的提取实际上就是对信号的一种分解,网络底层通道数对应信号分解时基的个数,通道内单个特征对应基分解时的时间点。提出的卷积自编码器以及对网络结构的分析可为后续科研技术人员构建卷积神经网络提供指导。 展开更多
关键词 深度学习 卷积神经网络 自动编码器 轴承故障诊断
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堆叠自编码网络性能优化及其在滚动轴承故障诊断中的应用 被引量:32
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作者 张西宁 向宙 +1 位作者 夏心锐 李立帆 《西安交通大学学报》 EI CAS CSCD 北大核心 2018年第10期49-56,87,共9页
为了解决堆叠自编码网络在参数较多时的梯度弥散问题,对网络每层的编码值进行了统计分析,发现大部分分布于激活函数的饱和区,这直接导致了神经元权值梯度的消失。为此,引入了一种标准化策略,将神经元按照样本进行归一化,然后引入两个待... 为了解决堆叠自编码网络在参数较多时的梯度弥散问题,对网络每层的编码值进行了统计分析,发现大部分分布于激活函数的饱和区,这直接导致了神经元权值梯度的消失。为此,引入了一种标准化策略,将神经元按照样本进行归一化,然后引入两个待学习参数进行缩放和平移,最后通过激活函数输出到下一级神经元。运用带标准化的堆叠自编码网络进行滚动轴承故障诊断,将振动信号的频谱输入到网络中。与普通堆叠自编码网络相比,该标准化策略可有效地使网络编码值均匀分布,如将第一层编码值的熵从0.88bit提高到了16.29bit。带标准化的堆叠自编码网络可有效提高网络的抗噪能力和训练速度:在凯斯西储大学滚动轴承数据集上,当人为添加噪声信号的信噪比为0dB时,识别正确率从16.18%提高到了100%;在实验室实测数据集上,不仅训练时间下降了37.22%,而且识别正确率从97.93%提高到了99.95%。对网络的编码值进行分析以及引入的标准化策略,可为科研技术人员构建堆叠自编码网络时提供参考,也为滚动轴承故障诊断提供了一种策略。 展开更多
关键词 故障诊断 堆叠自编码网络 标准化 滚动轴承
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一种新型磁流体加速度传感器 被引量:2
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作者 张西宁 夏心锐 +1 位作者 向宙 张雯雯 《西安交通大学学报》 EI CAS CSCD 北大核心 2019年第2期1-8,79,共9页
为了解决传统磁流体加速度传感器体积大、灵敏度低、线性度差、使用频率范围低等缺点,设计了一种新型磁流体加速度传感器。采用圆柱形永磁铁作为惯性质量,将加速度转化为磁场的变化,利用高灵敏度线性霍尔检测磁场变化,从而实现加速度到... 为了解决传统磁流体加速度传感器体积大、灵敏度低、线性度差、使用频率范围低等缺点,设计了一种新型磁流体加速度传感器。采用圆柱形永磁铁作为惯性质量,将加速度转化为磁场的变化,利用高灵敏度线性霍尔检测磁场变化,从而实现加速度到电信号的转变。通过仿真和实验分别对磁流体的悬浮效应、阻尼效应以及圆柱形永磁铁的磁场分布情况进行了研究,结果表明:在永磁铁体积较小的情况下,永磁铁受到的悬浮力很小;在磁场作用下,磁流体具有非常优越的阻尼性能。基于永磁铁的磁场分布情况的研究结果,选取磁场变化梯度最大且线性度最好的位置安装霍尔元件,从而提高传感器灵敏度。利用振动实验台,对所设计的传感器性能进行实验验证,结果表明,新型磁流体加速度传感器具有较好的线性度和较大的可用频率范围,在其他结构不变的前提下,磁流体的使用将加速度传感器的可用频率范围提高了256%。本文为研究磁流体的悬浮效应和阻尼效应提供了一种策略,也为加速度传感器的研究和改进提供了一种新的思路。 展开更多
关键词 加速度传感器 磁流体 霍尔元件 永磁铁
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基于核质遗传原理建立多重PCR检测方法鉴定阿胶中马、驴源性成分及皮张种源 被引量:9
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作者 谌阳 王文君 +3 位作者 付明 徐国强 周翔 刘榜 《遗传》 CAS CSCD 北大核心 2020年第10期1028-1035,共8页
阿胶(Asini Colla Corii)及其原料皮张源性成分的鉴定是对阿胶真实性的一种保障,阿胶生产企业和市场监管部门急需马、驴、骡皮张以及阿胶中源性成分鉴别的有效检测方法。本研究基于马、驴核基因组和线粒体基因组筛选物种特异性DNA序列... 阿胶(Asini Colla Corii)及其原料皮张源性成分的鉴定是对阿胶真实性的一种保障,阿胶生产企业和市场监管部门急需马、驴、骡皮张以及阿胶中源性成分鉴别的有效检测方法。本研究基于马、驴核基因组和线粒体基因组筛选物种特异性DNA序列作为检测靶标,设计马、驴特异性引物,建立了鉴别马、驴、骡皮张以及鉴定阿胶中马和驴源性成分的多重PCR方法。结果显示,本文所建立的方法可用于阿胶源性成分及皮张种源的鉴别,其特异性强,只在目标物种中扩增出目的条带,而非目标物种中没有任何扩增产物,而且灵敏度能达到0.2 ng,可为阿胶生产企业和市场监管部门提供技术支撑。 展开更多
关键词 阿胶 核基因 线粒体基因 多重PCR 马、驴源性成分
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区分自编码网络及其在滚动轴承故障特征提取中的应用 被引量:6
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作者 向宙 张西宁 +1 位作者 张雯雯 余迪 《西安交通大学学报》 EI CAS CSCD 北大核心 2019年第8期47-55,140,共10页
针对传统自编码网络在特征自动提取过程中仅以重构误差最小为目的而导致的分类信息模糊问题,提出了一种区分自编码网络。该网络在自编码网络的隐层连接一个全连接层,加上Softmax分类器,将分类器的输出与标签信息的交叉熵添加到原始的损... 针对传统自编码网络在特征自动提取过程中仅以重构误差最小为目的而导致的分类信息模糊问题,提出了一种区分自编码网络。该网络在自编码网络的隐层连接一个全连接层,加上Softmax分类器,将分类器的输出与标签信息的交叉熵添加到原始的损失函数中,以该复合损失函数最小为目标对网络进行训练。将上一层区分自编码网络的隐层作为下一层区分自编码网络的输入,依次堆叠形成堆叠区分自编码网络。运用改进前后的堆叠自编码网络进行滚动轴承故障特征自动提取,分别在实验室定转速和变转速多载荷数据集上进行了测试。定量计算改进前后网络提取特征的类内距和类间距,区分自编码网络将类内距减少8.26%,类间距增加23.02%。运用3种常用分类器对两种网络提取的特征和42个人工提取的特征分别进行故障分类,结果显示,在定转速数据集上,区分型网络提取的特征和人工提取特征的分类效果相当,均高于传统型网络提取的特征;但是在变转速多载荷数据上,区分型网络提取的特征明显优于另外两类特征。定量计算和故障诊断的结果表明,区分型网络具有良好的不随工况变化的特征自动提取能力。提出的区分型自编码网络可广泛应用在机械故障诊断的特征提取阶段,为工程技术人员实现特征自动提取提供了一种解决方案。 展开更多
关键词 深度学习 自编码 特征提取 轴承故障诊断
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基于OFD格式的电子印章技术应用研究 被引量:4
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作者 马超 周翔 +1 位作者 方镇林 张敏 《电子科学技术》 2017年第4期151-154,共4页
OFD是一种较流行的版式文档标准,其对PDF等其它版式文档的电子签章功能已然实现。就目前而言,国内基于OFD格式的电子印章技术尚属于起步阶段,技术力量相对薄弱。本文主要研究了基于OFD格式的电子印章技术的应用,供读者参考借鉴。
关键词 电子印章技术 应用 文档
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Function of microglia and macrophages in secondary damage after spinal cord injury 被引量:36
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作者 xiang zhou Xijing He Yi Ren 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第20期1787-1795,共9页
Spinal cord injury (SCI) is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary... Spinal cord injury (SCI) is a devastating type of neurological trauma with limited therapeutic op- portunities. The pathophysiology of SCI involves primary and secondary mechanisms of injury. Among all the secondary injury mechanisms, the inflammatory response is the major contrib- utor and results in expansion of the lesion and further loss of neurologic function. Meanwhile, the inflammation directly and indirectly dominates the outcomes of SCI, including not only pain and motor dysfunction, but also preventingneuronal regeneration. Microglia and macrophages play very important roles in secondary injury. Microglia reside in spinal parenchyma and survey the microenvironment through the signals of injury or infection. Macrophages are derived from monocytes recruited to injured sites from the peripheral circulation. Activated resident microglia and monocyte-derived macrophages induce and magnify immune and inflammatory responses not only by means of their secretory moleculesand phagocytosis, but also through their influence on astrocytes, oligodendrocytes and demyelination. In this review, we focus on the roles of mi- croglia and macrophages in secondary injury and how they contribute to the sequelae of SCI. 展开更多
关键词 astrocytes cytokines CHEMOKINES DEMYELINATION inflammation OLIGODENDROCYTES MI/M2 activation MACROPHAGES MICROGLIA secondary damage spinal cord injury
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Factors predicting sensory and motor recovery after the repair of upper limb peripheral nerve injuries 被引量:12
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作者 Bo He Zhaowei Zhu +6 位作者 Qingtang Zhu xiang zhou Canbin Zheng Pengliang Li Shuang Zhu Xiaolin Liu Jiakai Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第6期661-672,共12页
OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles d... OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles describing outcomes after the repair of median, ulnar, radial, and digital nerve injuries in humans with a publication date between 1 January 1990 and 16 February 2011. STUDY SELECTION: The following types of article were selected: (1) clinical trials describ- ing the repair of median, ulnar, radial, and digital nerve injuries published in English; and (2) studies that reported sufficient patient information, including age, mechanism of injury, nerve injured, injury location, defect length, repair time, repair method, and repair materials. SPSS 13.0 software was used to perform univariate and multivariate logistic regression analyses and to in- vestigate the patient and intervention factors associated with outcomes. MAIN OUTCOME MEASURES: Sensory function was assessed using the Mackinnon-Dellon scale and motor function was assessed using the manual muscle test. Satisfactory motor recovery was defined as grade M4 or M5, and satisfactory sensory recovery was defined as grade S3+ or S4. RESULTS: Seventy-one articles were included in this study. Univariate and multivariate logistic regression analyses showed that repair time, repair materials, and nerve injured were inde- pendent predictors of outcome after the repair of nerve injuries (P 〈 0.05), and that the nerve injured was the main factor affecting the rate of good to excellent recovery. CONCLUSION: Predictors of outcome after the repair of peripheral nerve injuries include age, gender, repair time, repair materials, nerve injured, defect length, and duration of follow-up. 展开更多
关键词 nerve regeneration peripheral nerve injury outcome predictors nerve repair upperlimb univariate analysis PROGNOSIS 863 Program neural regeneration
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In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging 被引量:7
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作者 Yan Yin xiang zhou +3 位作者 Xin Guan Yang Liu Chang-bin Jiang Jing Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第6期909-915,共7页
Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-der... Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI. 展开更多
关键词 nerve regeneration brain injury NEUROIMAGING FERUMOXYTOL superparamagnetic ironoxide particles human adipose-derived stem cells middle cerebral artery occlusion intracerebralinjection magnetic resonance imaging enhanced susceptibility-weighted angiography image modifiedneurological severity scores RATS Prussian blue staining neural regeneration
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Proximal gastrectomy with jejunal interposition and TGRY anastomosis for proximal gastric cancer 被引量:15
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作者 Ping Zhao Shuo-Meng Xiao +3 位作者 Ling-Chao Tang Zhi Ding xiang zhou Xiao-Dong Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第25期8268-8273,共6页
AIM: To compare the short-term outcomes of patients who underwent proximal gastrectomy with jejunal interposition (PGJI) with those undergoing total gastrectomy with Roux-en-Y anastomosis (TGRY).
关键词 Proximal gastric cancer Proximalgastrectomy with jejunal interposition Total gastrectomy with Roux-en-Y anastomosis
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