停车诱导系统在我国的停车场应用方面还不广泛,通过分析射频识别(radio frequency identification,RFID)技术的工作原理及优良特性,设计了基于RFID的停车场诱导系统的硬件和软件系统,并运用该系统的工作流程,模拟实现停车场停车路径实...停车诱导系统在我国的停车场应用方面还不广泛,通过分析射频识别(radio frequency identification,RFID)技术的工作原理及优良特性,设计了基于RFID的停车场诱导系统的硬件和软件系统,并运用该系统的工作流程,模拟实现停车场停车路径实时诱导,利用系统程序响应过程,准确地介绍了系统工作机制.展开更多
AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate...AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate at the ratio of 2:1) for 24 h.Cytotoxicity and apoptosis were evaluated by 3-(4,5-dmethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and Annexin V/propidium iodide staining,respectively.Cellular total lipid was determined using a photocolorimetric method after Nile red staining,and triglyceride content was measured using an enzymatic kit.To study the effects of Sch B on steatosis,L-02 cells were treated with Sch B (1-100 μmol/L) in the absence or presence of 1 mmol/L FFA for 24 h,and cellular total lipid and triglyceride levels were measured.To explore the mechanisms of action of Sch B in the steatotic L-02 cells,mRNA levels of several regulators of hepatic lipid metabolism including adipose differentiation related protein (ADRP),sterol regulatory element binding protein 1 (SREBP-1),peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ were measured by quantitative real-time polymerase chain reaction (PCR),and protein levels of ADRP and SREBP-1 were measured by immunoblotting.RESULTS:Treatment with 1 mmol/L FFA for 24 h induced intracellular lipid accumulation in L-02 cells comparable to that in human steatotic livers without causing apparent apoptosis and cytotoxicity.Sch B mitigated cellular total lipid and triglyceride accumulations in the steatotic L-02 cells in a dose-dependent manner.Quantitative real-time PCR and Western blot analyses revealed that treatment of L-02 cells with 100 μmol/L Sch B reverted the FFA-stimulated up-regulation of ADRP and SREBP-1.CONCLUSION:Sch B inhibits FFA-induced steatosis in L-02 cells by,at least in part,reversing the up-regulation of ADRP and SREBP-1.展开更多
The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by...The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by the van't Hoff equation model. The metastable zone width at various cooling rates was measured, and some parameters of nucleation kinetic were calculated using the Ny'vlt theory. Furthermore, the induction period of various temperatures and supersaturation ratios was also measured. According to classical nucleation theory, some nucleation parameters and interfacial energy was calculated through the induction time(t_(ind)) data. Homogeneous nucleation tended to occur when the supersaturation is high, whereas heterogeneous nucleation was more likely to occur when the supersaturation is low.展开更多
Xcc （Xanthomonas citri subsp, citri） causes citrus bacterial canker, a leaf, stem and fruit spotting disease that affects most commercial citrus species and cultivars. Copper compounds, widely used for management of...Xcc （Xanthomonas citri subsp, citri） causes citrus bacterial canker, a leaf, stem and fruit spotting disease that affects most commercial citrus species and cultivars. Copper compounds, widely used for management of this pathogen, have been reported as inducers of a VBNC （viable but non-culturable state） in plant pathogenic bacteria. VBNC may be considered as a state preceding bacterial death or as a survival mechanism under adverse conditions. Several experiments were performed to characterize the reversibility and persistence of the VBNC state in Xcc. VBNC was induced in low nutrient medium or with amendment of copper at concentrations used for field disease control. The VBNC condition was demonstrated to persist up to 150 days after copper treatment and was reversed after the addition of culture media without copper or amendment with citrus leaf extract. Xcc viability was evaluated by recovery of colonies on culture media, confirmed by membrane integrity, respiratory activity and by real-time RT-PCR targeting a sequence from the gumD gene. Besides, the colonies recovered were pathogenic on citrus leaves. These results confirm that the VBNC state in Xcc is inducible and reversible and therefore may occur in the phyllosphere when Xcc is under copper stress or starvation.展开更多
Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds...Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds on CYP3A. A quantitative real time PCR assay was developed and validated for the absolute quantification of CYP3A1 and CYP3A2 mRNA.Specific primers of CYP3A1,CYP3A2 and GAPDH（glyceraldehyde-3-phosphate dehydrogenase,as a house-keeping gene） were well designed.The relationship between threshold cycle（Ct） and logarithm of the concentrations of CYP3A1, CYP3A2 and GAPDH was linear ranged from 1 attomol/μL to 1×10~6 attomol/uL with great inter- and intra-assay reproducibility. This method was successfully applied to investigate the time courses of CYP3A1 and CYP3A2 mRNA induction in rat liver after 100 mg/kg dexamethasone（DEX） administration by intraperitoneal（i.p.） injection.The baseline levels of CYP3A1 and CYP3A2 mRNAs were 37.78 attomol/ug（total RNA） and 252.31 attomol/ug（total RNA）,respectively.CYP3A1 and CYP3A2 mRNA values increased gradually to their peak levels（19- and 8- fold vs.baseline） within 24 h and 42 h,respectively,and then returned to their baseline 60 h after DEX administration.展开更多
The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-ge...The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-gel method on a red copper test plate.From the obtained fluorescence images,the phase transition characteristics during the freezing and melting process of a water droplet were clearly observed.It was found that,at the beginning of the droplet freezing process,liquid water turned into ice at a very fast rate.Such phase transition process decreased gradually with time and the volume of frozen ice approached a constant value at the end of the icing process.In addition,the freezing time was found to reduce with the decrease of the test plate temperature.Besides,when the test plate temperature is relatively high,the effect of droplet volume on the freezing time is very significant.Over all,we provide some tentative insights into the microphysical process related to the icing and melting process of water droplets.展开更多
文摘停车诱导系统在我国的停车场应用方面还不广泛,通过分析射频识别(radio frequency identification,RFID)技术的工作原理及优良特性,设计了基于RFID的停车场诱导系统的硬件和软件系统,并运用该系统的工作流程,模拟实现停车场停车路径实时诱导,利用系统程序响应过程,准确地介绍了系统工作机制.
基金Supported by The Hong Kong Baptist University,No.FRG 08-09/II-30
文摘AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate at the ratio of 2:1) for 24 h.Cytotoxicity and apoptosis were evaluated by 3-(4,5-dmethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and Annexin V/propidium iodide staining,respectively.Cellular total lipid was determined using a photocolorimetric method after Nile red staining,and triglyceride content was measured using an enzymatic kit.To study the effects of Sch B on steatosis,L-02 cells were treated with Sch B (1-100 μmol/L) in the absence or presence of 1 mmol/L FFA for 24 h,and cellular total lipid and triglyceride levels were measured.To explore the mechanisms of action of Sch B in the steatotic L-02 cells,mRNA levels of several regulators of hepatic lipid metabolism including adipose differentiation related protein (ADRP),sterol regulatory element binding protein 1 (SREBP-1),peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ were measured by quantitative real-time polymerase chain reaction (PCR),and protein levels of ADRP and SREBP-1 were measured by immunoblotting.RESULTS:Treatment with 1 mmol/L FFA for 24 h induced intracellular lipid accumulation in L-02 cells comparable to that in human steatotic livers without causing apparent apoptosis and cytotoxicity.Sch B mitigated cellular total lipid and triglyceride accumulations in the steatotic L-02 cells in a dose-dependent manner.Quantitative real-time PCR and Western blot analyses revealed that treatment of L-02 cells with 100 μmol/L Sch B reverted the FFA-stimulated up-regulation of ADRP and SREBP-1.CONCLUSION:Sch B inhibits FFA-induced steatosis in L-02 cells by,at least in part,reversing the up-regulation of ADRP and SREBP-1.
基金Supported by the National Natural Science Foundation of China(21206109)China Ministry of Science and Major National Scientific Instrument Development Project(21527812)
文摘The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by the van't Hoff equation model. The metastable zone width at various cooling rates was measured, and some parameters of nucleation kinetic were calculated using the Ny'vlt theory. Furthermore, the induction period of various temperatures and supersaturation ratios was also measured. According to classical nucleation theory, some nucleation parameters and interfacial energy was calculated through the induction time(t_(ind)) data. Homogeneous nucleation tended to occur when the supersaturation is high, whereas heterogeneous nucleation was more likely to occur when the supersaturation is low.
文摘Xcc （Xanthomonas citri subsp, citri） causes citrus bacterial canker, a leaf, stem and fruit spotting disease that affects most commercial citrus species and cultivars. Copper compounds, widely used for management of this pathogen, have been reported as inducers of a VBNC （viable but non-culturable state） in plant pathogenic bacteria. VBNC may be considered as a state preceding bacterial death or as a survival mechanism under adverse conditions. Several experiments were performed to characterize the reversibility and persistence of the VBNC state in Xcc. VBNC was induced in low nutrient medium or with amendment of copper at concentrations used for field disease control. The VBNC condition was demonstrated to persist up to 150 days after copper treatment and was reversed after the addition of culture media without copper or amendment with citrus leaf extract. Xcc viability was evaluated by recovery of colonies on culture media, confirmed by membrane integrity, respiratory activity and by real-time RT-PCR targeting a sequence from the gumD gene. Besides, the colonies recovered were pathogenic on citrus leaves. These results confirm that the VBNC state in Xcc is inducible and reversible and therefore may occur in the phyllosphere when Xcc is under copper stress or starvation.
基金National Integrity Innovational Technology Platform of New Drug and Development(Grant No.2009ZX09301- 010)
文摘Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds on CYP3A. A quantitative real time PCR assay was developed and validated for the absolute quantification of CYP3A1 and CYP3A2 mRNA.Specific primers of CYP3A1,CYP3A2 and GAPDH（glyceraldehyde-3-phosphate dehydrogenase,as a house-keeping gene） were well designed.The relationship between threshold cycle（Ct） and logarithm of the concentrations of CYP3A1, CYP3A2 and GAPDH was linear ranged from 1 attomol/μL to 1×10~6 attomol/uL with great inter- and intra-assay reproducibility. This method was successfully applied to investigate the time courses of CYP3A1 and CYP3A2 mRNA induction in rat liver after 100 mg/kg dexamethasone（DEX） administration by intraperitoneal（i.p.） injection.The baseline levels of CYP3A1 and CYP3A2 mRNAs were 37.78 attomol/ug（total RNA） and 252.31 attomol/ug（total RNA）,respectively.CYP3A1 and CYP3A2 mRNA values increased gradually to their peak levels（19- and 8- fold vs.baseline） within 24 h and 42 h,respectively,and then returned to their baseline 60 h after DEX administration.
基金supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry and Science and Techology Commission of Shanghai Municipality(Grant No.11DZ2260400)
文摘The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-gel method on a red copper test plate.From the obtained fluorescence images,the phase transition characteristics during the freezing and melting process of a water droplet were clearly observed.It was found that,at the beginning of the droplet freezing process,liquid water turned into ice at a very fast rate.Such phase transition process decreased gradually with time and the volume of frozen ice approached a constant value at the end of the icing process.In addition,the freezing time was found to reduce with the decrease of the test plate temperature.Besides,when the test plate temperature is relatively high,the effect of droplet volume on the freezing time is very significant.Over all,we provide some tentative insights into the microphysical process related to the icing and melting process of water droplets.
