The true stress-strain curves of Ti-6Al-2Zr-1Mo-1V alloy were achieved by a series of isothermal compression tests with height reduction of 60% under the deformation temperatures of 1073-1323 K and the strain rates of...The true stress-strain curves of Ti-6Al-2Zr-1Mo-1V alloy were achieved by a series of isothermal compression tests with height reduction of 60% under the deformation temperatures of 1073-1323 K and the strain rates of 0.01-10s 1.The critical conditions for the onset of DRX were attained when the value of d /d,where strain hardening rate d /d,reached the minimum which corresponds to an inflection of θ versus σ curve.Thus,two important potential parameters,critical strain and critical stress,were identified,and expressed as εc/εp=0.37-0.60,σc/σp=0.81-0.91.Furthermore,by the regression analysis for conventional hyperbolic sine equation,the main material parameters such as α,β,n,and DRX activation energy,Q,were calculated.In addition,the evolution of Q with strain rate and temperature was revealed as a 3D response surface.展开更多
提出一种基于骨架邻近像素匹配的线结构光条中心提取方法,分别在图像预处理阶段和光条中心提取阶段对传统方法进行改进.在图像预处理阶段,将马尔可夫随机场理论应用于二值图像去噪中,同时提出了一种基于连通域面积特性的ROI(region of i...提出一种基于骨架邻近像素匹配的线结构光条中心提取方法,分别在图像预处理阶段和光条中心提取阶段对传统方法进行改进.在图像预处理阶段,将马尔可夫随机场理论应用于二值图像去噪中,同时提出了一种基于连通域面积特性的ROI(region of interest)提取方法.在光条中心提取阶段,首先提出了一种光条骨架剪枝算法,对细化ROI得到的光条骨架进行剪枝、平滑,之后综合考虑光条图像的几何特性和灰度分布特性,基于邻近分析对ROI内各像素进行划分,继而求取出灰度重心,最后经Savitzky-Golay滤波后实现光条中心提取.实验结果表明,所提方法对不同类型光条的提取适用性强,相较于Steger法精度更高,且速度在其基础上提高了约6.98倍.展开更多
规模自动化工业生产中的集群数控机床因各种故障导致停机而造成生产线效率的下降,若能及时准确地预测故障对数控机床进行预检预修有利于提高全线生产效率。在工业智能制造背景下,以数据驱动为支撑,数控机床积累的大量历史故障报警数据...规模自动化工业生产中的集群数控机床因各种故障导致停机而造成生产线效率的下降,若能及时准确地预测故障对数控机床进行预检预修有利于提高全线生产效率。在工业智能制造背景下,以数据驱动为支撑,数控机床积累的大量历史故障报警数据为依托,设计了一种基于Word2vec和LSTM-SVM的故障报警预测方法对机床未来可能发生的故障进行预测。首先通过词嵌入技术将报警文本向量化,然后将报警向量作为输入构建长短期记忆神经网络(long short term memory network,LSTM)预测模型,并使用支持向量机(support vector machine,SVM)代替传统的softmax作为模型的末端分类器,实验结果表明该方法具有更高的预测准确率。展开更多
Tetrandrine （Tet）, the main active constituent of Stephania tetrandra root, has been demonstrated to alleviate adjuvant-induced arthritis in rats. The present study was designed to investigate the effects of Tet on ...Tetrandrine （Tet）, the main active constituent of Stephania tetrandra root, has been demonstrated to alleviate adjuvant-induced arthritis in rats. The present study was designed to investigate the effects of Tet on the migration and invasion of rheumatoid arthritis fibroblast-like synovioeytes （RA-FLS） and explore the underlying mechanisms. By using cultures of primary FLS isolated from synoviums of RA patients and cell line MH7A, Tet （0.3, 1 μmol L-1） was proven to significantly impede migration and invasion of RA-FLS, but not cell proliferation. Tet also greatly reduced the activation and expressions of matrix degrading enzymes MMP-2/9, the expression of F-actin and the activation of FAK, which controlled the morphologic changes in migration process of FLS. To identify the key signaling pathways by which Tet exerts anti-migration effect, the specific inhibitors of multiple signaling pathways LY294002, Triciribine, SP600125, U0126, SB203580, and PDTC （against PI3K, Akt, JNK, ERK, p38 MAPK and NF-kB-p65, respectively） were used. Among them, LY294002, Triciribine, and SP600125 were shown to obviously inhibit the migration of MH7A cells. Consistently, Tet was able to down-regulate the activation of Akt and JNK as demonstrated by Western blotting assay. Moreover, Tet could reduce the expressions of migration-related proteins Rho GTPases Rac 1, Cdc42, and RhoA in MH7A cells. In conclusion, Tet can impede the migration and invasion of RA-FLS, which provides a plausible explanation for its protective effect on RA. The underlying mechanisms involve the reduction of the expressions of Racl, Cdc42, and RhoA, inhibition of the activation of Akt and JNK, and subsequent down-regulation of activation and/or expressions of MMP-2/9, F-actin, and FAK.展开更多
Bergenin, isolated from the herb of Saxifrage stolonifera Curt.(Hu-Er-Cao) has hepatoprotective, anti-inflammatory, antitussive, and neuroprotective activities. The aim of the present study was to establish a simple, ...Bergenin, isolated from the herb of Saxifrage stolonifera Curt.(Hu-Er-Cao) has hepatoprotective, anti-inflammatory, antitussive, and neuroprotective activities. The aim of the present study was to establish a simple, rapid, and sensitive RP-HPLC method for determination of bergenin in rat plasma and compare its oral pharmacokinetic behaviors in normal and CCl_4-induced hepatic injury rats. With norisoboldine as an internal standard, chromatographic separation was performed on a C_(18) analytical column with acetonitrile and water(11 : 89, V/V) containing 0.1% formic acid as the mobile phase. A good linearity was obtained over the range of 100^(–1)0 000 ng·m L^(–1). The lower limit of quantification was 50 ng·m L~(^(–1)). The developed method was successfully applied to a study of the pharmacokinetic difference of bergenin(100 mg·kg^(–1)) between normal and hepatic injury rats after oral administration. Marked alterations of pharmacokinetic parameters in hepatic injury rats were observed. Compared to normal rats, the AUC_((0–∞)) of bergenin in hepatic injury rats was elevated to 2.11-fold and C_(max) was increased by 130%, whereas CL value was only 55% of the normal rats, suggesting that the systemic exposure of bergenin was significantly increased under hepatic injury status.展开更多
To develop a simple and highly sensitive high performance liquid chromatography with electrospray ionization mass spectrometric(LC-ESI-MS) method for the simultaneous determination of madecassoside and its major metab...To develop a simple and highly sensitive high performance liquid chromatography with electrospray ionization mass spectrometric(LC-ESI-MS) method for the simultaneous determination of madecassoside and its major metabolite madecassic acid in rat plasma, and compare the pharmacokinetics of the two compounds in normal and collagen-induced arthritis(CIA) rats. Glycyrrhetinic acid was used as the internal standard(IS). Chromatographic separation was accomplished on an Inertsil ODS-3 column, using a gradient elution with the mobile phase composed of acetonitrile and water acidified with 0.1%(V/V) formic acid. Detection was achieved by ESI-MS under the negative selected ion monitoring(SIM) mode. In normal and CIA rats, madecassoside(30 mg·kg-1) was orally administered for 21 consecutive days from the day of arthritis onset. For madecassoside, the linear range was 10–1 000 ng·mL-1 with the square regression coefficient(r) of 0.998 9, while for madecassic acid, the linear range was 10–500 ng·mL-1 with the square regression coefficient(r) of 0.996 1. The lower limit of quantification was 10 ng·mL-1 for both analytes. The intra- and inter-day precision ranged from 1.78% to 13.42% for madecassoside and 2.30% to 14.90% for madecassic acid, and the accuracy was between –0.95% and 6.30% for madecassoside and between –1.48% and 5.34% for madecassic acid. The average recoveries of madecassoside, madecassic acid and IS from spiked plasma samples were > 81%. The developed method was successfully applied to the pharmacokinetic study of madecassoside and madecassic acid in rats after an oral administration of madecassoside. During initial 7 days of dosing, the cmax and AUC of madecassoside were greatly decreased and Vd/F was markedly increased in CIA rats, and no significant difference was observed on the first day of dosing. In contrast, the T1/2, cmax and AUC of madecassic acid were significantly increased, and Ke of madecassic acid was greatly decreased in CIA rats compared with normal rats. Along with repeated administration of madecassoside, the differences of pharmacokinetic parameters of both madecassoside and madecassic acid between CIA and normal rats gradually subsided. The pharmacokinetic characteristics of both madecassoside and madecassic acid in rats were significantly altered by arthritis status, and the differences of pharmacokinetic parameters between arthritis and normal rats coincide with the severity of arthritis.展开更多
基金Project(2022YFB3705103)supported by the National Key R&D Program,ChinaProject(2023CDJXY-020)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(cstc2021jcyj-msxmX1085)supported by Chongqing Natural Science Foundation General Project,China。
基金Project(2012ZX04010081)supported by the National Key Technologies R&D Program of ChinaProject(cstc2009aa3012-1)supported by the Science and Technology Committee of Chongqing,ChinaProject(CDJZR12130045)supported by the Fundamental Research Funds for the Central Universities,China
文摘The true stress-strain curves of Ti-6Al-2Zr-1Mo-1V alloy were achieved by a series of isothermal compression tests with height reduction of 60% under the deformation temperatures of 1073-1323 K and the strain rates of 0.01-10s 1.The critical conditions for the onset of DRX were attained when the value of d /d,where strain hardening rate d /d,reached the minimum which corresponds to an inflection of θ versus σ curve.Thus,two important potential parameters,critical strain and critical stress,were identified,and expressed as εc/εp=0.37-0.60,σc/σp=0.81-0.91.Furthermore,by the regression analysis for conventional hyperbolic sine equation,the main material parameters such as α,β,n,and DRX activation energy,Q,were calculated.In addition,the evolution of Q with strain rate and temperature was revealed as a 3D response surface.
文摘提出一种基于骨架邻近像素匹配的线结构光条中心提取方法,分别在图像预处理阶段和光条中心提取阶段对传统方法进行改进.在图像预处理阶段,将马尔可夫随机场理论应用于二值图像去噪中,同时提出了一种基于连通域面积特性的ROI(region of interest)提取方法.在光条中心提取阶段,首先提出了一种光条骨架剪枝算法,对细化ROI得到的光条骨架进行剪枝、平滑,之后综合考虑光条图像的几何特性和灰度分布特性,基于邻近分析对ROI内各像素进行划分,继而求取出灰度重心,最后经Savitzky-Golay滤波后实现光条中心提取.实验结果表明,所提方法对不同类型光条的提取适用性强,相较于Steger法精度更高,且速度在其基础上提高了约6.98倍.
文摘规模自动化工业生产中的集群数控机床因各种故障导致停机而造成生产线效率的下降,若能及时准确地预测故障对数控机床进行预检预修有利于提高全线生产效率。在工业智能制造背景下,以数据驱动为支撑,数控机床积累的大量历史故障报警数据为依托,设计了一种基于Word2vec和LSTM-SVM的故障报警预测方法对机床未来可能发生的故障进行预测。首先通过词嵌入技术将报警文本向量化,然后将报警向量作为输入构建长短期记忆神经网络(long short term memory network,LSTM)预测模型,并使用支持向量机(support vector machine,SVM)代替传统的softmax作为模型的末端分类器,实验结果表明该方法具有更高的预测准确率。
基金supported by the National Natural Science Foundation of China(No.81373426)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Tetrandrine （Tet）, the main active constituent of Stephania tetrandra root, has been demonstrated to alleviate adjuvant-induced arthritis in rats. The present study was designed to investigate the effects of Tet on the migration and invasion of rheumatoid arthritis fibroblast-like synovioeytes （RA-FLS） and explore the underlying mechanisms. By using cultures of primary FLS isolated from synoviums of RA patients and cell line MH7A, Tet （0.3, 1 μmol L-1） was proven to significantly impede migration and invasion of RA-FLS, but not cell proliferation. Tet also greatly reduced the activation and expressions of matrix degrading enzymes MMP-2/9, the expression of F-actin and the activation of FAK, which controlled the morphologic changes in migration process of FLS. To identify the key signaling pathways by which Tet exerts anti-migration effect, the specific inhibitors of multiple signaling pathways LY294002, Triciribine, SP600125, U0126, SB203580, and PDTC （against PI3K, Akt, JNK, ERK, p38 MAPK and NF-kB-p65, respectively） were used. Among them, LY294002, Triciribine, and SP600125 were shown to obviously inhibit the migration of MH7A cells. Consistently, Tet was able to down-regulate the activation of Akt and JNK as demonstrated by Western blotting assay. Moreover, Tet could reduce the expressions of migration-related proteins Rho GTPases Rac 1, Cdc42, and RhoA in MH7A cells. In conclusion, Tet can impede the migration and invasion of RA-FLS, which provides a plausible explanation for its protective effect on RA. The underlying mechanisms involve the reduction of the expressions of Racl, Cdc42, and RhoA, inhibition of the activation of Akt and JNK, and subsequent down-regulation of activation and/or expressions of MMP-2/9, F-actin, and FAK.
基金supported by Health Innovation Personnel Training Project of Changzhou City(No.CWKJ 2010-368)Changzhou High Level Health Personnel Training Project
文摘Bergenin, isolated from the herb of Saxifrage stolonifera Curt.(Hu-Er-Cao) has hepatoprotective, anti-inflammatory, antitussive, and neuroprotective activities. The aim of the present study was to establish a simple, rapid, and sensitive RP-HPLC method for determination of bergenin in rat plasma and compare its oral pharmacokinetic behaviors in normal and CCl_4-induced hepatic injury rats. With norisoboldine as an internal standard, chromatographic separation was performed on a C_(18) analytical column with acetonitrile and water(11 : 89, V/V) containing 0.1% formic acid as the mobile phase. A good linearity was obtained over the range of 100^(–1)0 000 ng·m L^(–1). The lower limit of quantification was 50 ng·m L~(^(–1)). The developed method was successfully applied to a study of the pharmacokinetic difference of bergenin(100 mg·kg^(–1)) between normal and hepatic injury rats after oral administration. Marked alterations of pharmacokinetic parameters in hepatic injury rats were observed. Compared to normal rats, the AUC_((0–∞)) of bergenin in hepatic injury rats was elevated to 2.11-fold and C_(max) was increased by 130%, whereas CL value was only 55% of the normal rats, suggesting that the systemic exposure of bergenin was significantly increased under hepatic injury status.
基金financially supported by the National Natural Science Foundation of China(No.81374038,81173631)the Jiangsu Overseas Research&Training Program for University Prominent Young&Middle-aged Teachers and Presidents+1 种基金sponsored by Qing Lan Project,College Students Innovation Project for the R&D of Novel Drugs(No.J1030830)partially funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘To develop a simple and highly sensitive high performance liquid chromatography with electrospray ionization mass spectrometric(LC-ESI-MS) method for the simultaneous determination of madecassoside and its major metabolite madecassic acid in rat plasma, and compare the pharmacokinetics of the two compounds in normal and collagen-induced arthritis(CIA) rats. Glycyrrhetinic acid was used as the internal standard(IS). Chromatographic separation was accomplished on an Inertsil ODS-3 column, using a gradient elution with the mobile phase composed of acetonitrile and water acidified with 0.1%(V/V) formic acid. Detection was achieved by ESI-MS under the negative selected ion monitoring(SIM) mode. In normal and CIA rats, madecassoside(30 mg·kg-1) was orally administered for 21 consecutive days from the day of arthritis onset. For madecassoside, the linear range was 10–1 000 ng·mL-1 with the square regression coefficient(r) of 0.998 9, while for madecassic acid, the linear range was 10–500 ng·mL-1 with the square regression coefficient(r) of 0.996 1. The lower limit of quantification was 10 ng·mL-1 for both analytes. The intra- and inter-day precision ranged from 1.78% to 13.42% for madecassoside and 2.30% to 14.90% for madecassic acid, and the accuracy was between –0.95% and 6.30% for madecassoside and between –1.48% and 5.34% for madecassic acid. The average recoveries of madecassoside, madecassic acid and IS from spiked plasma samples were > 81%. The developed method was successfully applied to the pharmacokinetic study of madecassoside and madecassic acid in rats after an oral administration of madecassoside. During initial 7 days of dosing, the cmax and AUC of madecassoside were greatly decreased and Vd/F was markedly increased in CIA rats, and no significant difference was observed on the first day of dosing. In contrast, the T1/2, cmax and AUC of madecassic acid were significantly increased, and Ke of madecassic acid was greatly decreased in CIA rats compared with normal rats. Along with repeated administration of madecassoside, the differences of pharmacokinetic parameters of both madecassoside and madecassic acid between CIA and normal rats gradually subsided. The pharmacokinetic characteristics of both madecassoside and madecassic acid in rats were significantly altered by arthritis status, and the differences of pharmacokinetic parameters between arthritis and normal rats coincide with the severity of arthritis.
