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Protective mechanisms of picroside Ⅱ on aquaporin-4 expression in a rat model of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2010年第6期5卷 411-417页

作者： Zhen Li Xinying xu qin Li Meizeng Zhang wei Shen Institute of Cerebrovascular Diseases Qingdao University Medical College Qingdao 266021 Shandong Province China Neurology Department of Affiliated Hospital Qingdao University Medical College Qingdao 266021 Shandong Province China Teaching and Research Center of Integrative Medicine Qingdao University Medical College Qingdao 266021 Shandong Province China

BACKGROUND： Aquaporin-4 （AQP-4） over-expression following cerebral ischemia results in cerebral edema. Picroside Ⅱ has been shown to exhibit a neuroprotective effect on neuronal apoptosis. However, few reports have addressed the neuroprotective mechanisms and therapeutic times following cerebral ischemic reperfusion injury. OBJECTIVE： To explore the neuroprotective effects and ideal treatment window for picroside Ⅱ treatment of middle cerebral artery occlusion and reperfusion injury in rats. DESIGN, TIME AND SETTING; A randomized, controlled, animal experiment was performed at Institute of Cerebrovascular Diseases, qingdao University Medical College from September 2008 to May 2009. MATERIALS： Picroside II was purchased from Tianjin Kuiqing Medical Technology, China. METHODS： A total of 165 adult, healthy, male, Wistar rats were randomly assigned to sham-surgery （n = 15）, model （n = 75）, and treatment groups （n = 75）. Rats in the model and treatment groups underwent middle cerebral artery occlusion and reperfusion through the use of an intraluminal monofilament suture on the left external-internal carotid artery, The treatment group was injected with 1.0% picroside Ⅱ （10 mg/kg） into the tail vein, and the model and sham-surgery groups were injected with 0.1 mol/L phosphate buffered saline （250 μL）. MAIN OUTCOME MEASURES： Neurological functional scores were evaluated using the Longa＇s method; cerebral infarction volume was detected through the use of tetrazolium chlodde staining; cellular apoptosis was determined through the use of the in situ end-labeling method; aquaporin-4 expression was measured using fluorescence labeling analysis and reverse transcription polymerase chain reaction technique. RESULTS： At 0.5 hour following cerebral ischemic injury, neurological functional scores were low, and a small infarction focus was detected in the ischemic cortex of the model group. Along with prolonged ischemia and an increased number of apoptosis-positive cells, AQP-4 mRN

关键词： picroside Ⅱ cerebral ischemia and reperfusion apoptosis aquaporin-4 therapeutic time window neuroprotection

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Representations of Inverse Covariances by Differential Operators

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Advances in Atmospheric Sciences 2005年第2期22卷 181-198页

作者： qin xu NationalOceanicandAtmosphericAdministration／NationalSevereStormsLaboratory NormanOklahoma73069

In the cost function of three- or four-dimensional variational dataassimilation, each term is weighted by the inverse of its associated error covariance matrix and thebackground error covariance matrix is usually much larger than the other covariance *** the background error covariances are traditionally normalized and parameterized by simplesmooth homogeneous correlation functions, the covariance matrices constructed from these correlationfunctions are often too large to be inverted or even manipulated. It is thus desirable to finddirect representations of the inverses of background error correlations. This problem is studied inthis paper. In particular, it is shown that the background term can be written into ∫ dx∣Dυ(x)∣~2, that is, a squared 1/2 norm of a vector differential operator D, called theD-operator, applied to the field of analysis increment υ(x). For autoregressive correlationfunctions, the D-operators are of finite orders. For Gaussian correlation functions, the D-operatorsare of infinite order. For practical applications, the Gaussian D-operators must be truncated tofinite orders. The truncation errors are found to be small even when the Gaussian D-operators aretruncated to low orders. With a truncated D-operator, the background term can be easily constructedwith neither inversion nor direct calculation of the covariance matrix. D-operators are also derivedfor non-Gaussian correlations and transformed into non-isotropic forms.

关键词： differential operator inverse background covariance data assimilation

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Effects of argon blowing at tundish upper nozzle on multiphase flow behavior in nozzle

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Journal of Iron and Steel Research International 2022年第4期29卷 588-600页

作者： xu-feng qin Chang-gui Cheng Yang Li wei-li Wu Yan Jin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

In continuous casting,the argon blowing at the tundish upper nozzle is usually used to prevent nozzle clogging,whose effect is closely related to the migration of argon bubbles and the flow behavior of the liquid steel in the ***,to investigate the effects of argon blowing at the tundish upper nozzle on multiphase flow behavior in nozzle,a threedimensional model of the tundish–nozzle–mold was established for numerical *** results indicate that the argon bubbles injected from the inner wall of the tundish upper nozzle first move downward along the nozzle wall under the action of the liquid *** the distance from the tundish upper nozzle increases,the argon bubbles gradually diffuse to the center of the *** with no argon blowing,the liquid steel velocity increases in the center of the nozzle and decreases near the wall with argon *** increasing the argon flow rate,the concentration of bubbles in the nozzle increases,and the process of bubble group diffusion to the center region of the nozzle speeds *** in turn increases the liquid steel velocity at the center of the nozzle but reduces near the *** increasing the casting speed,the concentration of bubbles in the nozzle decreases,the length of the bubble group near the nozzle wall is extended,and the liquid steel velocity at the center region and near-wall region of the nozzle *** mechanism of argon blowing at the tundish upper nozzle to prevent nozzle clogging is mainly realized by the isolation effect of the argon bubble group on the inner wall of the nozzle.

关键词： Argon blowing Tundish upper nozzle Nozzle clogging Numerical simulation

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A Correction and Comments on“Multi-Scale Deep Neural Network(MscaleDNN)for Solving Poisson-Boltzmann Equation in Complex ***,28(5):1970–2001,2020”

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Communications in Computational Physics 2023年第5期33卷 1509-1513页

作者： Lulu Zhang wei Cai Zhi-qin John xu Institute of Natural Sciences and School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China Department of Mathematics Southern Methodist UniversityDallasTX 75275USA

This note provides a correction of a missing weight constant in the MscaleDNN formula and some comments on the performance of the corrected algorithm.

关键词： Multi-scale DNN PDE solver deep learning

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LightGCNet:基于轻量化卷积网络的深度色域压缩算法

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计算机科学与探索 2025年第1期19卷 196-210页

作者：杨晨徐昊朱佳伟吴秦柴志雷江南大学人工智能与计算机学院江苏无锡214122 江苏省模式识别与计算智能工程实验室江苏无锡214122

色域压缩是大色域向小色域进行转换时保持色彩信息的关键技术。经典算法虽计算快速,但处理结果缺乏细节且没有考虑人眼的感知特性,难以满足人们对色彩品质不断提升的要求。迭代算法处理效果更佳,但极其耗时,无法投入实际应用。针对上述... 详细信息

色域压缩是大色域向小色域进行转换时保持色彩信息的关键技术。经典算法虽计算快速,但处理结果缺乏细节且没有考虑人眼的感知特性,难以满足人们对色彩品质不断提升的要求。迭代算法处理效果更佳,但极其耗时,无法投入实际应用。针对上述问题,提出了轻量化的深度色域压缩方法,该方法可在逼近迭代算法计算效果的同时保持接近经典算法的速度。为色域压缩算法设计了LightGCNet模型,该网络中的双层卷积由DSC与DW卷积组合而成,相比常规U-Net,参数量与计算复杂度急剧降低。为进一步提高模型先验性,将预训练得到的DW卷积中多个核通道进行重聚焦操作以建立联系,最终权重由重聚焦权重和预训练权重组成。针对色相、明度、彩度这三个色彩属性,设计了色域压缩专用的损失函数。该函数不仅考虑了像素级损失,而且融合了图像感知损失,并联合色彩属性的多尺度信息进行加权,解决了深度色域压缩过程中细节丢失的问题。基于迭代算法生成标签以训练网络,联合学习目标色域特征与图像信息,实现了与迭代算法相当的效果。实验结果表明:该方法与业界经典的SGCK算法相比,iCID值降低了17.08%,SSIM值提高了5.30%。相比常规U-Net模型,LightGCNet参数量减少了82.96%,乘加次数从8.5GFLOPs大幅下降至2.2GFLOPs,使改良模型更适于低端设备部署。该模型在CPU上处理单幅512×512图像仅需0.208s,计算时间比迭代类算法减少99.92%。

关键词：色域压缩轻量化深度学习色彩管理

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Improved Pattern Clustering Algorithm for Recognizing Transversal Distribution of Steel Strip Thickness

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Journal of Iron and Steel Research International 2009年第5期16卷 50-55页

作者： TANG Cheng-long WANG Shi-gang LIANG qin-hua xu wei School of Mechanical and Dynamical Engineering Shanghai Jiao Tong University Shanghai 200240 China

Transversal distribution of the steel strip thickness in the entry section of the cold rolling mill seriously affects to the flatness and transversal thickness precision of the final products. Pattern clustering method is introduced into the steel rolling field and used in the patterns recognition of transversal distribution of the steel strip thickness. The well-known k-means clustering algorithm has the advantage of being easily completed, but still has some drawbacks. An improved k-means clustering algorithm is presented, and the main improvements include：（1） the initial clustering points are preselected according to the density queue of data objects; and （2） Mahalanobis distance is applied instead of Euclidean distance in the actual application. Compared to the patterns obtained from the common kmeans algorithm, the patterns identified by the improved algorithm show that the improved clustering algorithm is well suitable for the patterns＇ recognition of transversal distribution of steel strip thickness and it will be useful in online quality control system.

关键词： transversal thickness distribution pattern recognition improved k-means algorithm density queue

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A Criterion for Subnormality of Subgroups in Finite Groups

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Acta Mathematica Sinica,English Series 2012年第8期28卷 1575-1580页

作者： Hua Quan wei Hong Fei PAN Shu qin DONG xu SUN College of Mathematics and Information Sciences Guangxi University School of Mathematics Science Guangxi Teacher's Education University

Based on Wielandt＇s criterion for subnormality of subgroups in finite groups, we study 2-maximal subgroups of finite groups and present another subnormality criterion in finite solvable groups.

关键词： Finite group solvable group maximal subgroup subnormal subgroup semidirect

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Bifunctional metal–organic frameworks toward photocatalytic CO2reduction by post-synthetic ligand exchange

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Rare Metals 2019年第5期38卷 413-419页

作者： Xiao-Hui Chen qin wei Jin-Dui Hong Rong xu Tian-Hua Zhou School of Chemical Engineering Fuzhou UniversityFuzhou 350002China School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore 637459Singapore State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Photocatalytic reduction of CO2 to useful fuel has been identified as a promising strategy to address the energy and environmental *** of welldefined photocatalysts toward CO2 reduction has attracted increasing interest to gain insight into the reactive ***,by post-synthetic ligand exchange,a bifunctional Re-based metal–organic framework(MOF)was successfully *** not only serves as a photosensitizer but also acts as a catalyst for photochemical reduction of ***,it is found that a Re-based MOF containing 30%Re-based ligands displays improved activity compared to MOF with 100%Re-based *** work provides clues to the design and synthesis of bifunctional MOFs toward photocatalytic CO2 reduction.

关键词： Photocatalysis Metal-organic framework(MOF) CO2 reduction Post-synthesis

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Heterosis and heterotic patterns of maize germplasm revealed by a multiple-hybrid population under well-watered and drought-stressed conditions

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Journal of Integrative Agriculture 2022年第9期21卷 2477-2491页

作者： SANG Zhi-qin ZHANG Zhan-qin YANG Yu-xin LI Zhi-wei LIU Xiao-gang xu Yun-bi LI wei-hua Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Corps/Agricultural CollegeShihezi UniversityShihezi 832003P.R.China Xinjiang Academy of Agricultural and Reclamation Science Shihezi 832000P.R.China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China International Maize and Wheat Improvement Center(CIMMYT) El Batan Texcoco 56130Mexico

Understanding the heterosis in multiple environments between different heterotic groups is of fundamental importance in successful maize breeding. A total of 737 hybrids derived from 41 maize inbreds were evaluated over two years, with the aim of assessing the genetic diversity and their performance between heterotic groups under drought-stressed(DS) and well-watered(WW) treatments. A total of 38 737 SNPs were employed to assess the genetic diversity. The genetic distance(GD) between the parents ranged from 0.05 to 0.74, and the 41 inbreds were classified into five heterotic groups. According to the hybrid performance(high yield and early maturity between heterotic groups), the heterosis and heterotic patterns of Iowa Stiff Stalk Synthetic(BSSS)×Non-Stiff Stalk(NSS), NSS×Sipingtou(SPT) and BSSS×SPT were identified to be useful options in China’s maize breeding. The relative importance of general and specific combining abilities(GCA and SCA) suggests the importance of the additive genetic effects for grain yield traits under the WW treatment, but the non-additive effects under the DS treatment. At least one of the parental lines with drought tolerance and a high GCA effect would be required to achieve the ideal hybrid performance under drought conditions. GD showed a positive correlation with yield and yield heterosis in within-group hybrids over a certain range of GD. The present investigation suggests that the heterosis is due to the combined accumulation of superior genes/alleles in parents and the optimal genetic distance between parents, and that yield heterosis under DS treatment was mainly determined by the non-additive effects.

关键词： maize drought stress heterosis heterotic group heterotic pattern genetic distance

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The m6A methylation landscape stratifies hepatocellular carcinoma into 3 subtypes with distinct metabolic characteristics

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Cancer Biology & Medicine 2020年第4期17卷 937-952页

作者： Xiaotian Shen Beiyuan Hu Jing xu wei qin Yan Fu Shun Wang Qiongzhu Dong Lunxiu qin Department of General Surgery Huashan Hospital&Cancer Metastasis Institute&Institutes of Biomedical SciencesFudan UniversityShanghai 250040China Institutes of Biomedical Sciences Fudan UniversityShanghai 200032China Shanghai Medical College Fudan UniversityShanghai 200040China

Objective:Epigenetic aberration plays an important role in the development and progression of hepatocellular carcinoma(HCC).However,the alteration of RNA N6-methyladenosine(m6A)modifications and its role in HCC progression remain *** therefore aimed to provide evidence using bioinformatics ***:We comprehensively analyzed the m6A regulator modification patterns of 605 HCC samples and correlated them with metabolic alteration *** elucidated 390 gene-based m6A-related signatures and defined an m6Ascore to quantify m6A *** then assessed their values for predicting prognoses and therapeutic responses in HCC ***:We identified 3 distinct m6A modification patterns in HCC,and each pattern had distinct metabolic *** evaluation of m6A modification patterns using m6Ascores could predict the prognoses,tumor stages,and responses to sorafenib treatments of HCC patients.A nomogram based on m6Ascores showed high accuracy in predicting the overall survival of *** area under the receiver operating characteristic curve of predictions of 1,3,and 5-year overall survivals were 0.71,0.69,and 0.70 in the training cohort,and in the test cohort it was 0.74,0.75,and 0.71,respectively.M6Acluster C1,which corresponded to hypoactive mRNA methylation,lower expression of m6A regulators,and a lower m6Ascore,was characterized by metabolic hyperactivity,lower tumor stage,better prognosis,and lower response to sorafenib *** contrast,m6Acluster C3 was distinct in its hyperactive mRNA methylations,higher expression of m6A regulators,and higher m6Ascores,and was characterized by hypoactive metabolism,advanced tumor stage,poorer prognosis,and a better response to *** m6Acluster,C2,was intermediate between C1 and ***:HCCs harbored distinct m6A regulator modification patterns that contributed to the metabolic heterogeneity and diversity of *** of m6A gene signatures and the m6Ascore

关键词： Hepatocellular carcinoma RNA N6-methyladenosine,metabolism,bioinformatics,prognosis

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