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    题名 作者 年代 出处 被引量
1Insights into the Tectonic Fractures in the Yanchang Formation Interbedded Sandstone-Mudstone of the Ordos Basin Based on Core Data and Geomechanical Models显示文摘The distribution and intensity of tectonic fractures within geologic units are important to hydrocarbon exploration and development. Taken the Upper Triassic Yanchang Formation interbedded sandstone-mudstone in the Ordos Basin as an example, this study used the finite element method(FEM) based on geomechanical models to study the development of tectonic fractures. The results show that the sandstones tend to generate tectonic fractures more easily than mudstones with the same layer thickness, and the highest degree of tectonic fractures will be developed when the sandstone-mudstone thickness ratio is about 5.0. A possible explanation is proposed for the tectonic fracture development based on two important factors of rock brittleness and mechanical layer thickness. Generally, larger rock brittleness and thinner layer thickness will generate more tectonic fractures. In interbedded sandstone-mudstone formations, the rock brittleness increases with the increasing mechanical layer thickness, hence, these two factors will achieve a balance for the development of tectonic fractures when the sandstone-mudstone thickness ratio reaches a specific value, and the development degree of tectonic fractures is the highest at this value.JU Wei SUN Weifeng HOU Guiting 2015Acta Geologica Sinica(English Edition)2015,89,6:16
2Stable Initialization Scheme for K-Means Clustering显示文摘Though K-means is very popular for general clustering, its performance, which generally converges to numerous local minima, depends highly on initial cluster centers. In this paper a novel initialization scheme to select initial cluster centers for K-means clustering is proposed. This algorithm is based on reverse nearest neighbor (RNN) search which retrieves all points in a given data set whose nearest neighbor is a given query point. The initial cluster centers computed using this methodology are found to be very close to the desired cluster centers for iterative cluster-ing algorithms. This procedure is applicable to clustering algo-rithms for continuous data. The application of the proposed algo-rithm to K-means clustering algorithm is demonstrated. An ex-periment is carried out on several popular datasets and the results show the advantages of the proposed method.XU Junling XU Baowen ZHANG Weifeng ZHANG Wei HOU Jun 2009Wuhan University Journal of Natural Sciences2009,14,1:15
3Drug nanoclusters formed in confined nano-cages of CD-MOF: dramatic enhancement of solubility and bioavailability of azilsartan显示文摘Tremendous efforts have been devoted to the enhancement of drug solubility using nanotechnologies, but few of them are capable to produce drug particles with sizes less than a few nanometers. This challenge has been addressed here by using biocompatible versatile γ-cyclodextrin(γ-CD) metal-organic framework(CD-MOF) large molecular cages in which azilsartan(AZL) was successfully confined producing clusters in the nanometer range. This strategy allowed to improve the bioavailability of AZL in Sprague–Dawley rats by 9.7-fold after loading into CD-MOF. The apparent solubility of AZL/CD-MOF was enhanced by 340-fold when compared to the pure drug. Based on molecular modeling, a dual molecular mechanism of nanoclusterization and complexation of AZL inside the CD-MOF cages was proposed, which was confirmed by small angle X-ray scattering(SAXS) and synchrotron radiation-Fourier transform infrared spectroscopy(SR-FTIR) techniques. In a typical cage-like unit of CD-MOF, three molecules of AZL were included by the γ-CD pairs, whilst other three AZL molecules formed a nanocluster inside the 1.7 nm sized cavity surrounded by six γ-CDs. This research demonstrates a dual molecular mechanism of complexation and nanoclusterization in CD-MOF leading to significant improvement in the bioavailability of insoluble drugs.Yuanzhi He Wei Zhang Tao Guo Guoqing Zhang Wei Qin Liu Zhang Caifen Wang Weifeng Zhu Ming Yang Xiaoxiao Hu Vikramjeet Singh Li Wu Ruxandra Gref Jiwen Zhang 2019Acta Pharmaceutica Sinica B2019,9,1:13
4Propofol differentially induces unconsciousness and respiratory depression through distinct interactions between GABAa receptor and GABAergic neuron in corresponding nuclei显示文摘Propofol is the most commonly used intravenous anesthetic worldwide.It can induce loss of consciousness prior to the occurrence of severe respiratory suppression,which is also a pharmacodynamic feature of all general anesthetics.However,the neural mechanisms underlying this natural phenomenon are controversial and highly related to patient safety.In the present study,we demonstrated that the pharmacodynamic effects of propofol(50 and 100 μM)on suppression of consciousness-related excitatory postsynaptic currents in the medial prefrontal cortex(mPFC)and centromedian nucleus of the thalamus(CMT)were lower than those in the kernel respiratory rhythmogenesis nucleus pre-Botzinger complex(PrBo).Furthermore,we unexpectedly found that the GABAa receptor β3 subunit is the key target for propofol's action and that it is mutually and exclusively expressed in GABAergic neurons.It is also more abundant in the mPFC and CMT,but mainly co-localized with GABAergic neurons in the PrBo.As a result,the differentiated expression pattern should mediate more neuron suppression through the activation of GABAergic neurons in the mPFC and CMT at low doses of propofol(50 μM).However,PrBo GABAergic neurons were only activated by propofol at a high dose(100 μM).These results highlight the detailed pharmacodynamic effects of propofol on consciousness-related and respiration-related nuclei and provide the distinct interaction mechanism between the β3 subunit and GABAergic neurons in mediating the suppression of consciousness compared to the inhibition of respiration.Junli Jiang Yingfu Jiao Po Gao Wen Yin Wei Zhou Yunchun Zhang Yanjun Liu Daxiang Wen Yuan Wang Liang Zhou Tian Yu Weifeng Yu 2021Acta Biochimica et Biophysica Sinica2021,53,8:11
5Phylogenetics of varied subtypes of avian influenza viruses in China: potential threat to humans显示文摘Weifeng Shi Wei Li Xianbin Li Joel Haywood Juncai Ma George F.Gao Di Liu 2014Protein & Cell2014,5,4:9
6Comparative study on local and global mechanical properties of bobbin tool and conventional friction stir welded 7085-T7452 aluminum thick plate显示文摘7085-T7452 plates with a thickness of 12 mm were welded by conventional single side and bobbin tool friction stir welding(SS-FSW and BB-FSW, respectively) at different welding parameters. The temperature distribution, microstructure evolution and mechanical properties of joints along the thickness direction were investigated, and digital image correlation(DIC) was utilized to evaluate quantitatively the deformation of different zones during tensile tests. The results indicated that heat-affected zone(HAZ), the local softening region, was responsible for the early plastic deformation and also the fracture location for SS-FSW samples, while a rapid fracture was observed in weld nugget zone(WNZ) before yield behavior for all BB-FSW specimens. The ultimate tensile strength(UTS) of SS-FSW joints presented the highest value of 410 MPa, 82% of the base material, at a rotational speed of 300 rpm and welding speed of 60 mm/min,much higher than that of BB-FSW joints, with a joint efficiency of only 47%. This should be attributed to the Lazy S defect produced by a larger extent of heat input during the BB-FSW process. The whole joint exhibited a much higher elongation than the slices. Scanning electron microscopic(SEM) analysis of the fracture morphologies showed that joints failed through ductile fracture for SS-FSW and brittle fracture for BB-FSW.Weifeng Xu Yuxuan Luo Wei Zhang Mingwang Fu 2018Journal of Materials Science & Technology2018,34,1:7
7Improvement of Ductility of Powder Metallurgy Titanium Alloys by Addition of Rare Earth Element显示文摘Ti-4.5AI-6.0Mo-1.5Fe, Ti-6AI-1Mo-1Fe 和 Ti-6AI-4V 合金被混合元素的粉末冶金学(下午) 准备微观结构和机械性质上的 Nd 的过程,和效果被扫描电子显微镜学(SEM ) 调查,传播电子显微镜学(TEM ) 和 X 光检查衍射(XRD ) 。因为液相的小数量发生在 sintering 期间, Nd 的增加由 1% 的最大的增长稍微增加了 sintered 钛合金的密度,这被发现。Nd 的增加在张力的力量的改进上显示出小效果,当延伸显著地被改进时。例如,没有 13percent 的 Nd 的增加, Ti-4.5AI-6.0Mo-1.5Fe 的延伸能在 1.2 wt % 的一个 Nd 内容从 1% 被增加。Yong LIU Lifang CHEN Weifeng WEI Huiping TANG Bin LIU Baiyun HUANG 2006Journal of Materials Science & Technology2006,22,4:7
8Extractive distillation: Advances in conceptual design, solvent selection,and separation strategies显示文摘Extractive distillation(ED) is one of the most promising approaches for the separation of the azeotropic or closeboiling mixtures in the chemical industry. The purpose of this paper is to provide a broad overview of the recent development of key aspects in the ED process involving conceptual design, solvent selection, and separation strategies. To obtain the minimum entrainer feed flow rate and reflux ratio for the ED process, the conceptual design of azeotropic mixture separation based on a topological analysis via thermodynamic feasibility insights involving residue curve maps, univolatility lines, and unidistribution curves is presented. The method is applicable to arbitrary multicomponent mixtures and allows direct screening of design alternatives. The determination of a suitable solvent is one of the key steps to ensure an effective and economical ED process. Candidate entrainers can be obtained from heuristics or literature studies while computer aided molecular design(CAMD) has superiority in efficiency and reliability. To achieve optimized extractive distillation systems, a brief review of evaluation method for both entrainer design and selection through CAMD is presented. Extractive distillation can be operated either in continuous extractive distillation(CED) or batch extractive distillation(BED), and both modes have been well-studied depending on the advantages in flexibility and low capital costs. To improve the energy efficiency, several configurations and technological alternatives can be used for both CED and BED depending on strategies and main azeotropic feeds. The challenge and chance of the further ED development involving screening the best potential solvents and exploring the energy-intensive separation strategies are discussed aiming at promoting the industrial application of this environmentally friendly separation technique.Shirui Sun Liping Lü Ao Yang Shun'an Wei Weifeng Shen 2019Chinese Journal of Chemical Engineering2019,27,6:6
9Continuous reassortments with local chicken H9N2 virus underlie the human-infecting influenza A (H7N9) virus in the new influenza season, Guangdong, China显示文摘亲爱的编辑,Wenbao Qi Weifeng Shi Wei Li Lihong Huang Huanan Li Ying Wu Jinghua Yan Peirong Jiao Baoli Zhu Juncai Ma George F. Gao Ming Liao Di Liu 2014Protein & Cell2014,5,11:5
10Multi-functional polyethersulfone nanofibrous membranes with ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria显示文摘The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria,by virtue of the advantages of adsorption technology including high efficiency,energy conservation and ease of operation.Simultaneous removal of dyes and bacteria has been realized by some reported materials,but to achieve satisfactory adsorption amounts and rates remain an unmet goal for decades.Herein,a poly(methacrylatoethyl trimethyl ammonium chloride-co-methyl methacrylate)copolymer was synthesized,and then blended with polyethersulfone for the fabrication of nanofibrous membranes via electrospinning for the use of fast and massive removal of dyes and bacteria.Owing to the introduction of abundant quaternary ammonium groups,the maximum adsorption amount for methyl orange was up to 909.8 mg g^(-1).In addition,the modified nanofibrous membranes showed good recyclability,broad applications in severe environments,selective adsorption ability,and excellent dynamic removal performance.Especially,thanks to the abundant functional groups,the membranes showed fast adsorption ability for bacteria through electrostatic interaction.It should be noted that the clearance ratio for Staphylococcus aureus or Escherichia coli by 6 min of static adsorption could reach 93%or 90%for each.Additionally,dynamic removal ratio via filtration with the nanofibrous membranes could reach 99.7%for Staphylococcus aureus or 98.7%for Escherichia coli in 90 s.Therefore,the proposed approach towards the quaternary ammonium modified polyethersulfone nanofibrous membranes creates a new route for ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria in water remediation.Jianxu Bao Hang Li Yuanting Xu Shengqiu Chen Zhoujun Wang Chunji Jiang Huilin Li Zhiwei Wei Shudong Sun Weifeng Zhao Changsheng Zhao 2021Journal of Materials Science & Technology2021,,19:4
11Serum DKK1 as a protein biomarker for the diagnosis of hepatocellular carcinoma: a large-scale, multicentre study显示文摘Qiujin Shen Jia Fan Xin-Rong Yang Yexiong Tan Weifeng Zhao Yang Xu Ning Wang Yongdong Niu Zheng Wu Jian Zhou Shuang-Jian Qiu Ying-Hong Shi Bin Yu Ning Tang Wei Chu Min Wang Jinhua Wu Zhigang Zhang Shengli Yang Jianren Gu Hongyang Wang Wenxin Qin 2012Lancet Oncology2012,,8:4
12Review of regional carbon counting methods for the Chinese major ecological engineering programs显示文摘In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland Conversion Program, the Desertification Combating Program, and the Protection Forest System Construction Program. There is a growing need to quantify the contributions of these programs to regional carbon stocks.However, the lack of widely accepted, robust methods is one of the key obstacles to quantification. The objective of this study was to review existing methods for quantifying regional carbon stocks and then recommend suitable ones for the Chinese ecological engineering programs. We expect that the recommended methods can be applied to elsewhere in the world where there are similar characteristics and objectives.Ji Zheng Xiaohua Wei Yuanqiu Liu Guohua Liu Weifeng Wang Wenfei Liu 2016Journal of Forestry Research2016,27,4:3
13Optimization of taste-masking on ibuprofen microspheres with selected structure features显示文摘The microsphere was a primary particulate system for taste-masking with unique structural features defined by production process. In this article, ibuprofen lipid microspheres of octadecanol and glycerin monostearate were prepared to mask the undesirable taste of ibuprofen via three kinds of spray congealing processes, namely, air-cooling, water-cooling and citric acid solution-cooling. The stereoscopic and internal structures of ibuprofen microspheres were quantitatively analyzed by synchrotron radiation X-ray micro-computed tomography(SR-μCT) to establish the relationship between the preparation process and microsphere architectures. It was found that the microstructure and morphology of the microspheres were significantly influenced by preparation processes as the primary factors to determine the release profiles and taste-masking effects. The sphericity of ibuprofen microspheres congealed in citric acid solution was higher than that of other two and its morphology was more regular than that being congealed in air or distilled water, and the contact angles between congealing media and melted ibuprofen in octadecanol and glycerin monostearate well demonstrated the structure differences among microspheres of three processes which controlled the release characteristics of the microspheres. The structure parameters like porosity, sphericity, and radius ratio from quantitative analysis were correlated well with drug release behaviors. The results demonstrated that the exterior morphology and internal structure of microspheres had considerable influences on the drug release behaviors as well as taste-masking effects.Wei Qin Yuanzhi He Zhen Guo Liu Zhang Li Wu Xianzhen Yin Shailendra Shakya Abi Maharjan Yan Tang Weifeng Zhu Jiwen Zhang 2019Asian Journal of Pharmaceutical Sciences2019,14,2:3
14A New Feature Selection Method for Text Clustering显示文摘Feature selection methods have been successfully ap-plied to text categorization but seldom applied to text clustering due to the unavailability of class label information. In this paper,a new feature selection method for text clustering based on expecta-tion maximization and cluster validity is proposed. It uses super-vised feature selection method on the intermediate clustering result which is generated during iterative clustering to do feature selec-tion for text clustering;meanwhile,the Davies-Bouldin's index is used to evaluate the intermediate feature subsets indirectly. Then feature subsets are selected according to the curve of the Davies-Bouldin's index. Experiment is carried out on several popular datasets and the results show the advantages of the proposed method.XU Junling XU Baowen ZHANG Weifeng CUI Zifeng ZHANG Wei 2007Wuhan University Journal of Natural Sciences2007,12,5:3
15Origin and diversity of novel avian influenza A H7N9 viruses causing human infection: phylogenetic, structural, and coalescent analyses显示文摘Di Liu Weifeng Shi Yi Shi Dayan Wang Haixia Xiao Wei Li Yuhai Bi Ying Wu Xianbin Li Jinghua Yan Wenjun Liu Guoping Zhao Weizhong Yang Yu Wang Juncai Ma Yuelong Shu Fumin Lei George F Gao 2013The Lancet2013,,9881:2
16Selective potassium uptake via biocompatible zeolite–polymer hybrid microbeads as promising binders for hyperkalemia显示文摘Patients with chronic kidney disease are at high risk of hyperkalemia that is associated with various lifethreatening complications.Treatments primarily rely on orally administered potassium binding agents,along with low curative effects and various side effects.Herein,direct serum potassium uptake was realized via zeolite–heparin-mimicking-polymer hybrid microbeads.The preparation process involved the synthesis of the heparin-mimicking polymer via the in situ cross-linking polymerization of acrylic acid and N-vinylpyrrolidone in polyethersulfone solution,the fabrication of microbeads via zeolite-mixing,electro-spraying and phase-inversion,and the subsequent aqueous-phase modifications based on ion-exchange and metal-leaching.An ultra-high(about 88%)amount of zeolite could be incorporated and well locked inside the polymer matrix.Potassium uptake capability was verified in water,normal saline and human serum,showing high selectivity and fast adsorption.The microbeads exhibited satisfying blood compatibility,negligible hemolysis ratio,prolonged clotting time,inhibited contact activation,and enhanced antifouling property toward serum proteins and cells.The proposed approach toward zeolite–heparin-mimicking-polymer hybrid microbeads provided a cheap,efficient and safe treatment protocol of hyperkalemia for the high-risk patients.Zhoujun Wang Wei Sun Zhiwei Wei Jianxu Bao Xin Song Yupei Li Haifeng Ji Jue Zhang Chao He Baihai Su Weifeng Zhao Changsheng Zhao 2021Bioactive Materials2021,6,2:2
17ISTC: A New Method for Clustering Search Results显示文摘A new common phrase scoring method is proposed according to term frequency-inverse document frequency (TFIDF) and independence of the phrase. Combining the two properties can help identify more reasonable common phrases, which improve the accuracy of clustering. Also, the equation to measure the in-dependence of a phrase is proposed in this paper. The new algo-rithm which improves suffix tree clustering algorithm (STC) is named as improved suffix tree clustering (ISTC). To validate the proposed algorithm, a prototype system is implemented and used to cluster several groups of web search results obtained from Google search engine. Experimental results show that the im-proved algorithm offers higher accuracy than traditional suffix tree clustering.ZHANG Wei XU Baowen ZHANG Weifeng XU Junling 2008Wuhan University Journal of Natural Sciences2008,13,4:2
18Dexmedetomidine maintains blood-brain barrier integrity by inhibiting Drp1-related endothelial mitochondrial dysfunction in ischemic stroke显示文摘Stroke is the second leading cause of death and long-term disability worldwide,which lacks effective treatment.Perioperative stroke is associated with much higher rates of mortality and disability.The neuroprotective role of dexmedetomidine(Dex),a highly selective agonist of alpha2-adrenergic receptor,has been reported in a stroke rat model,and it was found that pretreatment of Dex before stroke could alleviate blood–brain barrier(BBB)breakdown.However,the underlying mechanisms are still unknown.As the brain endothelial cells are the main constituents of BBB and in high demand of energy,mitochondrial function of endothelial cells plays an important role in the maintenance of BBB.Given that dynamin-related protein 1(Drp1)is a protein mediating mitochondrial fission,with mitochondrial fusion that balances mitochondrial morphology and ensures mitochondria function,the present study was designed to investigate the possible role of Drp1 in endothelial cells involved in the neuroprotective effects of Dex in ischemic stroke.Our results showed that preconditioning with Dex reduced infarction volume,alleviated brain water content and BBB damage,and improved neurological scores in middle cerebral artery occlusion rats.Meanwhile,Dex enhanced cell activity and decreased cell apoptosis in oxygen-glucose deprivation human brain microvascular endothelial cells in vitro.These protective effects of Dex were correlated with the mitochondrial morphology integrality of endothelial cells,mediated by increased phosphorylation of serine 637 in Drp1,and could be reversed byα2-adrenergic receptor antagonist Yohimbine and AMP-activated protein kinase inhibitor Compound C.These findings suggest new molecular pathways involved in the neuroprotective effects of Dex in ischemic stroke.As Dex is routinely used as a sedative drug clinically,our findings provide molecular evidence that it has perioperative neuroprotection from ischemic stroke.Wei Zhou Yunchun Zhang Yingfu Jiao Wen Yin Haiping Dong Saihong Xu Dan Tang Junli Jiang Jianlin Shao Zhenhong Wang Weifeng Yu 2021Acta Biochimica et Biophysica Sinica2021,53,9:2
19Effects of bias voltage on coating structures and anticorrosion performances of PA-PVD Al coated NdFeB magnets显示文摘Al coated NdFeB magnets were prepared by plasma-assisted-physical-vapor-deposition(PA-PVD)method fo r enhancing the corro sion resistance.Mo rphologies and structures were characterized by an Xray diffractometer and a scanning electron microscope.Corrosion behaviors of the samples with different bias voltages were studied by electrochemical methods and neutral salt spray test,respectively.The bias voltage during the deposition process was optimized according to the coating structures and corrosion resistances.The density and flatness of Al coating increase with increasing the bias voltage,and at the same time the thickness decreases.The coating density and thickness turn to be stable when bias voltage is 1800 V.Also,the corrosion behaviors of PA-PVD Al coatings in different media,such as NaOH,HNO_(3) and NaCl solutions,were studied.The self-corrosion potentials(E_(corr)) of PA-PVD Al coatings almost keep constant in NaOH and HNO_(3) solutions with diffe rent concentrations.However,the self-corrosion current densities(J_(corr)) decrease with the increasing concentrations.E_(corr) shifts to negative potential and J_(corr)decreases gradually when increasing the concentration of NaCl solution.The corrosion mechanisms of Al coatings are discussed based on the corrosion behaviors in different media.Yujie Cao Pengjie Zhang Wei Sun Weifeng Zhang Hanzhong Wei Jiquan Wang Bingshan Li Xiaofei Yi Guangqing Xu Yucheng Wu 2021Journal of Rare Earths2021,39,6:2
20Ubiquitin-specific protease 24 promotes EV71 infection by restricting K63-linked polyubiquitination of TBK1显示文摘TANK-binding kinase 1(TBK1)is an essential protein kinase for activation of interferon regulatory factor 3(IRF3)and induction of the type I interferons(IFN-I).Although the biochemical regulation of TBK1 activation has been studied,little is known about how enterovirus 71(EV71)employs the deubiquitinases(DUBs)to regulate TBK1 activation for viral immune evasion.Here,we found that EV71 infection upregulated the expression of ubiquitinspecific protease 24(USP24).Further studies revealed that USP24 physically interacted with TBK1,and can reduce K63-linked polyubiquitination of TBK1.Knockdown of USP24 upregulated TBK1 K63-linked polyubiquitination,promoted the phosphorylation and nuclear translocation of IRF3,and in turn improved IFN-I production during EV71 infection.As a consequence,USP24 knockdown dramatically inhibited EV71 infection.This study revealed USP24 as a novel regulator of TBK1 activation,which promotes the understanding of immune evasion mechanisms of EV71 and could provide a potential strategy for treatment of EV71 infection.Lichao Zang Jin Gu Xinyu Yang Yukang Yuan Hui Guo Wei Zhou Jinhong Ma Yan Chen Yumin Wu Hui Zheng Weifeng Shi 2023Virologica Sinica2023,38,1:2
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