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不同ES细胞系体外定量神经分化的比较 被引量:3
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作者 汤富酬 韩嵘 +1 位作者 薛友纺 尚克刚 《遗传》 CAS CSCD 北大核心 2001年第5期439-441,共3页
利用视黄酸 (RA)诱导小鼠胚胎干细胞通过悬浮类胚培养法体外定量分化为神经样细胞。结果显示能够进行种系嵌合的MESPU2 2细胞系与不能进行种系嵌合的MESPU13细胞系的体外神经分化比例在统计学上没有明显差异。此结果对于人的胚胎干细胞... 利用视黄酸 (RA)诱导小鼠胚胎干细胞通过悬浮类胚培养法体外定量分化为神经样细胞。结果显示能够进行种系嵌合的MESPU2 2细胞系与不能进行种系嵌合的MESPU13细胞系的体外神经分化比例在统计学上没有明显差异。此结果对于人的胚胎干细胞全能性的鉴定与检测有重要启示。 展开更多
关键词 胚胎干细胞 体外神经分化 RA诱导 定量分化
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The quantified analysis of China's GM cotton yield capacity by C-D function and stochastic frontier model
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作者 张涛 薛宝娣 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期11-13,共3页
Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increas... Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increased by the use of genetically modified (GM) varieties. 展开更多
关键词 GM cotton yield capacity C D function stochastic frontier model
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A DSS DEVELOPMENT AND APPLICATION FOR SUSTAINABLE DEVELOPMENT
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作者 沈惠璋 王浣尘 +2 位作者 刘铎 亢政刚 丁雷 《Transactions of Tianjin University》 EI CAS 2000年第1期22-27,共6页
The characteristics of sustainable development problems in the developing countries is discussed.In order to develop and use decision support system (DSS) for supporting sustainable development problem decision making... The characteristics of sustainable development problems in the developing countries is discussed.In order to develop and use decision support system (DSS) for supporting sustainable development problem decision making in the developing countries,this paper presents a strategy of constructing the DSS for sustainable development.A methodology of representing the model of sustainable development problems and developing a nonprocedural modeling language that is used to define sustainable development problems,a methodology of numeric and non numeric operation based theorem proving is given in this paper. 展开更多
关键词 decision support system sustainable development qualitative analysis quantitative research evolution behaviors
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Quantitative analysis of globularization and modeling of TC17 alloy with basketweave microstructure 被引量:2
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作者 Hao-yu PANG Jiao LUO +3 位作者 Zhi-gang ZHANG Wen-chao HAN Keng-feng XU Miao-quan LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期850-867,共18页
The globularization behavior and mechanism of TC17 alloy with basketweave microstructure were investigated, and the models of dynamic and static globularization kinetics were established. The quantitative and metallog... The globularization behavior and mechanism of TC17 alloy with basketweave microstructure were investigated, and the models of dynamic and static globularization kinetics were established. The quantitative and metallographic results show that the globularization of α phase is sensitive to the parameters of deformation and heat treatment. By EBSD analysis, the formation and evolution mechanisms of intra-α boundaries are related to discontinuous dynamic recrystallization and continuous dynamic recrystallization, which can form α grains with high and low misorientations between neighbour grains after the heat treatment, respectively. Based on the globularization behavior and mechanism, two modified JMAK models are developed to predict the dynamic and static globularization kinetics, and the mean absolute relative errors(MARE) of 10.67% and 13.80% indicate the accuracy of the dynamic and static globularization kinetics models. The results of this work can provide guidance for controlling microstructure of titanium alloy. 展开更多
关键词 TC17 alloy basketweave microstructure globularization quantitative analysis kinetics model
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Identification of Ni_xS_y on Industrial Spent S Zorb Sorbents by Using XPS and TPR-MS 被引量:2
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作者 Yuan Hui Qiu Limei +4 位作者 Xu Guangtong Xin Mudi Shi Yanqiang Chen Shuai Zou Kang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第3期42-47,共6页
Three industrial spent S Zorb sorbents extracted from production line were studied with XRD, TPR-MS and XPS. The characterization results of XPS and TPR-MS identified the existence of amorphous Ni_xS_y on industrial s... Three industrial spent S Zorb sorbents extracted from production line were studied with XRD, TPR-MS and XPS. The characterization results of XPS and TPR-MS identified the existence of amorphous Ni_xS_y on industrial spent S Zorb sorbents, while the existing XRD quantitative analysis methods can only provide the long-range order in phase information and the grain size of Ni metal. XPS is a powerful tool to investigate the chemical states of nickel atom and the depthwise distribution of nickel species on S Zorb sorbent. Ni_xS_y and Ni metal species coexist on the industrial spent sorbents, and their percentages to total nickel slightly change with the operating conditions in the surface layer. It proves that Ni_xS_y is a stable intermediate product rather than a transition state. The information can contribute to the better elucidation of S Zorb desulfurization mechanism and offer a new direction for selectivity optimization of industrial S Zorb sorbents. 展开更多
关键词 S Zorb SORBENT nickel sulfide reaction mechanism X-ray photoelectron spectroscopy
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Quantitative analysis of transforming growth factor beta 1 mRNA in patients with alcoholic liver disease 被引量:21
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作者 Wei-Xing Chen You-Ming Li Chao-Hui Yu Wei-Min Cai Min Zheng Feng-Chen,Department of Gastroenterology, The First Affiliated Hospital,Medical College of Zhejiang University,Hangzhou 310003,Zhejiang Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期379-381,共3页
AIM: To investigate the expression of the transforming growth factor beta 1(TGF-beta 1) mRNA in different stages of alcoholic liver disease (ALD) and its clinical value. METHODS: One hundred and seven male alcoholics ... AIM: To investigate the expression of the transforming growth factor beta 1(TGF-beta 1) mRNA in different stages of alcoholic liver disease (ALD) and its clinical value. METHODS: One hundred and seven male alcoholics were grouped by clinical findings into four groups: alcohol abusers without liver impairment (n =22), alcoholic steatosis (n =30); alcoholic hepatitis (n=31); and alcoholic cirrhosis(n=24). Using peripheral blood mononuclear cells (PBMC) as samples the gene expression of TGF-beta 1 was examined quantitatively by reverse transcription polymerase chain reaction (RT-PCR) and dot blot. There are 34 healthy subjects served as control. RESULTS: The expression of TGF-beta 1 from all ALD patients was significantly greater than that in controls (1.320 +/- 1.162 vs 0.808 +/- 0.276, P【0.001). The differences of the expressions were significant between the patients from each groups (alcoholic steatosis, alcoholic hepatitis and alcoholic cirrhosis) and the controls (1.168 +/- 0.852, 1.462 +/- 1.657, 1.329 +/- 0.610 vs 0.808 +/- 0.276, P【0.050). No significant differences of TGF -beta 1 mRNA expression were observed between alcohol abusers without liver impairment and controls. The expressions in patients with alcoholic hepatitis and alcoholic cirrhosis were significantly greater than that in alcohol abusers respectively (1.462 +/- 1.657, 1.329 +/- 0.610 vs 0.841 +/- 0.706, P【0.050). No significant differences of TGF-beta 1 mRNA expression were observed between alcoholic fatty liver men and alcohol abusers. CONCLUSION: TGF-beta 1 expression level can be a risk factor for alcoholic liver disease and might be related to the inflammatory activity and fibrosis of the liver in patients. 展开更多
关键词 Humans Liver Diseases Alcoholic MALE RNA Messenger Transforming Growth Factor beta
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Identification of indoor multi-component pollution gas aliasing peak based on JADE
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作者 王芳 李晋华 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期24-29,共6页
Monitoring indoor harmful gas can obtain the infrared spectra of mixed harmful gases.Since the absorption bands of mixed gases overlap and their qualitative and quantitative analyses are not easy,feature extraction me... Monitoring indoor harmful gas can obtain the infrared spectra of mixed harmful gases.Since the absorption bands of mixed gases overlap and their qualitative and quantitative analyses are not easy,feature extraction method based on joint approximative diagonalization of eigenmatrix(JADE)is proposed.By fully mining the hidden information of original data and analyzing higher-order statistics information of the data,each substance spectrum in the mixed gas can be accurately distinguished.In addition,a multi-dimensional data quantitative analysis model of the extracted independent source is established by using support vector machine(SVM)based on regular theory.The experimental results show that the correlation coefficients of the components of mixed gases is above 0.999 1by quantitative analysis,which verifies the accuracy of this feature extraction method. 展开更多
关键词 aliasing peak identification joint approximative diagonalization of eigenmatrix(JADE) quantitative analysis sup-port vector machine(SVM)
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A Dual Wavelength Differential First Derivative Spectrophotometric Method for Identification and Determination of Carbon Monoxide Generated During the Microsomal Metabolism of Xenobiotics in vitro
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作者 徐宏祥 刘志强 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第2期51-56,共6页
A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and... A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2~10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control. 展开更多
关键词 Dual wavelength differential first derivative spectrophotometry Carbon monoxide Trifluoroaniline Drug metabolism Hepatic microsomes Cytochrome P 450
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Determination of anthraquinone prodrug and its hydrolytically active compounds using RP-HPLC
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作者 段艳冰 余佳 +1 位作者 刘海峰 吉民 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期128-131,共4页
In order to study the hydrolytic characterization of an anti-inflammatory prodrug ( RI-1 ) in vitro, an effective, accurate and reliable method for the simultaneous determination of the prodrug and its two hydrolyti... In order to study the hydrolytic characterization of an anti-inflammatory prodrug ( RI-1 ) in vitro, an effective, accurate and reliable method for the simultaneous determination of the prodrug and its two hydrolytic active compounds is developed using reverse phase high-performance liquid chromatography (RP-HPLC). The chromatographic separation is performed on an ODS-2 C18 column (250 mm × 4. 6 mm, 5.0 μm particle size) with a simple elution program. The mobile phase is V( methanol) : V(0. 1% phosphoric acid solution) =90:10 (adjust pH to 2. 3). A wavelength of 225 nm and a mobile phase flow rate of 1.0 mL/min are utilized for the quantitative analysis. Excellent linear behaviors over the investigated concentration ranges are observed with values of R2 higher than 0. 999 for all the analytes. The validated method is successfully applied to the simultaneous determination of the prodrug and its active components can be used to detect hydrolytic characterization in vitro. 展开更多
关键词 high-performance liquid chromatography (HPLC) quantitative analysis anthraquinone prodrug active components
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Rice Repetitive DNA Sequence RRD3:a Plant Promoter and Its Application to RNA Interference
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作者 仲健 王宏斌 +2 位作者 张党权 刘兵 王金发 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期258-266,共9页
Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes ... Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes and a CAAT-box, and promoter activity was shown in Escherichia coli and mammalian expression systems. Here, we inserted the RRD3 fragment into the plant promoter-capture vector, pCAMBIA1391Z, and examined whether the RRD3 fragment has promoter activity in plants. Transgenic tobacco and rice calli both showed β-glucuronidase (GUS) activity, indicating that RRD3 can act as a promoter in both monocot and dicot plants. Based on the promoter characteristic of RRD3, we designed a plant universal binary vector, pCRiRRD3, which is suitable for performing researches on plant RNA interference. This vector has two multiple cloning sites to facilitate sense and antisense cloning of the target sequence, separated by an intron fragment of 200 bp. The efficiency of the vector for gene silencing was assayed by histochemical and quantitative fluorometric GUS assays in transgenic tobacco. These research results suggested that this plant RNAi vector pCRiRRD3 can effectively perform gene silencing researches on both monocot and dicot plants. 展开更多
关键词 RRD3 PROMOTER GUS histochemical assay quantitative fluorometric GUS assay RNA interference
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Detection and Quantitative Analysis of Dominant Bacteria On Aging Flue-cured Tobacco Leaves 被引量:3
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作者 Fang LIU Zhe ZHAO Mingqin ZHAO 《Agricultural Science & Technology》 CAS 2016年第11期2611-2614,共4页
[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, ... [Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging. 展开更多
关键词 Flue-cured tobacco AGING Real-time PCR SYBR Green DNA copies
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Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China 被引量:5
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作者 SU Yong-Hong FENG Qi +2 位作者 ZHU Gao-Feng SI Jian-Hua ZHANG Yan-Wu 《Pedosphere》 SCIE CAS CSCD 2007年第3期331-342,共12页
Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolutio... Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids (TDS) in the groundwater showed a great variation, with 62.5% of the samples being brackish (TDS ≥ 1 000 mg L^-l). The groundwater system showed a gradual hydro-chemical zonation composed of Na^+ -HCO3^-, Na^+ -Mg^2+ -SO4 ^2 -Cl^-, and Na^+ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^+, K^+, Cl^-, SO^4 , and Ca^2+, but other processes, such as mixing, Na^+ exchange for Ca^2+ and Mg^2+, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts. 展开更多
关键词 Ejin Sub-Basin groundwater quality Heihe River human impact water resources development
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Mesenchymal Stem Cells Express Low Levels of Cardiomyogenic Genes and Show Limited Plasticity towards Cardiomyogenic Phenotype
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作者 Juliana Lott de Carvalho Danilo Roman Campos +4 位作者 Maira Souza Oliveira Jader Santos Cruz Nathalia Martins Breyner Dawidson Assis Gomes Alfredo Miranda de Goes 《Journal of Life Sciences》 2013年第9期950-964,共15页
Mesenchymal stem cell differentiation towards osteogenic, chondrogenic and adipogenic lineages have been extensively described and reproduced in the literature. In contrast, cardiomyogenic differentiation still remain... Mesenchymal stem cell differentiation towards osteogenic, chondrogenic and adipogenic lineages have been extensively described and reproduced in the literature. In contrast, cardiomyogenic differentiation still remains largely controversial. In this study the authors aim to shed new light into this unclear phenomenon and test whether BMMSC (bone marrow mesenchymal stem cells) and ATMSC (adipose tissue derived mesenchymal stem cells) are able to differentiate into functional cardiomyocytes, investigating two differentiation protocols. AT and BMMSC behaved differently when cultured in differentiation media and presented lower levels of proliferation and alkaline phosphatase production, expression of cardiomyocyte-specific transcription factors such as GATA-4, Nkx2-5 and proteins such as ct and 13 Myosin Heavy Chains. Furthermore, MSC started to express higher levels of Connexin-43 and c~ sarcomeric actinin protein. Unfortunately, though, MSC did not present cardiomyocyte-like electrophysiological properties. In order to analyze a possible explanation for such limited plasticity, the authors decided to address the issue using a quantitative approach. Gene expression was quantified by Real time PCR, and, for the first time, the authors show that a possible explanation for limited plasticity of MSC is that even though differentiated cells presented differential gene expression, the levels of key cardiomyogenic genes did not reach expression levels presented by adult cardiomyocytes, nor were maintained along differentiation, reaching peaks at 4 days of stimulation, and decaying thereafter. 展开更多
关键词 Mesenchymal stem cells cardiomyogenic differentiation limited plasticity in vitro differentiation
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The Effect of Separatism on the Society: Quantitative Analysis on the World Values Survey
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作者 Dwiyatna Widinugraha James Kiwanuka Tondo 《Journalism and Mass Communication》 2015年第10期537-543,共7页
In the 21st century, world politics appeared to far from resolved condition in terms of power sharing among the elites, thus created separatism movements in many parts of the world. These movements caused some changes... In the 21st century, world politics appeared to far from resolved condition in terms of power sharing among the elites, thus created separatism movements in many parts of the world. These movements caused some changes in the society that is nowadays seen as a multicultural. Using World Values Survey's data, this study revealed that separatism would cause people to less likely agree on ethnic diversity benefit. Further, when the result is tested by elaboration model, economic condition was found as important factor on how people saw ethnic diversity benefit among the society. 展开更多
关键词 world politics effect of separatism ethnic diversity national identity
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QUANTIFIED COST-BALANCED ROUTING SCHEME FOR OVERLAY MULTICAST
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作者 Lu Jun Ruan Qiuqi 《Journal of Electronics(China)》 2006年第6期882-887,共6页
This paper focuses on the quantitative analysis issue of the routing metrics tradeoff problem, and presents a Quantified Cost-Balanced overlay multicast routing scheme (QCost-Balanced) to the metric tradeoff problem b... This paper focuses on the quantitative analysis issue of the routing metrics tradeoff problem, and presents a Quantified Cost-Balanced overlay multicast routing scheme (QCost-Balanced) to the metric tradeoff problem between overlay path delay and access bandwidth at Multicast Server Nodes (MSN) for real-time ap-plications over Internet. Besides implementing a dynamic priority to MSNs by weighing the size of its service clients for better efficiency, QCost-Balanced tradeoffs these two metrics by a unified tradeoff metric based on quantitative analysis. Simulation experiments demonstrate that the scheme achieves a better tradeoff gain in both two metrics, and effective performance in metric quantitative control. 展开更多
关键词 Multicast routing Overlay network Quantified analysis
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Quantitative analysis on the contribution of industrial structure change to sustainable development: a case study of Fujian Province
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作者 Lin Qing Wang Ying 《Ecological Economy》 2009年第1期20-27,共8页
Development and sustainability are the core connotation of sustainable development. Sustainability of economic development and the provision capability of resources and environment are two aspects of sustainable devel... Development and sustainability are the core connotation of sustainable development. Sustainability of economic development and the provision capability of resources and environment are two aspects of sustainable development. The former ones are the foundation of the latter ones. Industrial structure has a close relationship with sustainable development. The optimization of industrial structure is the important base for the sustainable development of modern economy and also the important ways of the sustainable utilization of resources and environment. The intensive growth effect of industrial structure change has the meaning of sustainable development. This paper reviews and explains the theory on the contribution of industrial structure change to sustainable development, builds the calculation model through introducing the coeff icient of industrial structure change, makes an empirical study on the contribution of industrial structure change to sustainable development in Fujian, and puts forward ways and policies of optimizing industrial structure both among industries and inside the industry in the process of industrial structure change. 展开更多
关键词 Industrial structure change Sustainable development CONTRIBUTION
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Quantitative Interpretation of Polarization SFG Vibrational Spectra of Air/Methanol Interface
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作者 Hui Wu Wen-kai Zhang +2 位作者 Wei Gan Zhi-feng Cui Hong-fei Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第3期187-189,共3页
Even though in IR and Raman spectra of liquid methanol there is always an apparent feature for the asymmetric stretching mode of the CH3 group around 2970 cm^-1, this feature has not been observed in the Sum Frequency... Even though in IR and Raman spectra of liquid methanol there is always an apparent feature for the asymmetric stretching mode of the CH3 group around 2970 cm^-1, this feature has not been observed in the Sum Frequency Generation Vibrational Spectroscopy (SFG-VS) in any polarizations from the air/methanol interface. Here we present a treatment based on a corrected bond additivity model to quantitatively interpret the SFG-VS of the air/methanol interface from the IR and Raman spectra of liquid methanol. 展开更多
关键词 Sum frequency generation Bond additivity model Raman polarizability
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Characterization and expression of sweetfish (Plecoglossus altivelis) cathepsin D 被引量:2
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作者 Yu JIAO Chang-Hong LI +1 位作者 Xin-Jiang LU Jiong CHEN 《Zoological Research》 CAS CSCD 北大核心 2014年第4期294-299,共6页
Cathepsin D (CTSD) is a lysosomal acidic endoproteinase that plays an important role in immune response, In this study, we obtained sweetfish (Plecoglossus altivelis) CTSD (PaCTSD) via de-novo transcriptome sequ... Cathepsin D (CTSD) is a lysosomal acidic endoproteinase that plays an important role in immune response, In this study, we obtained sweetfish (Plecoglossus altivelis) CTSD (PaCTSD) via de-novo transcriptome sequencing of sweetfish macrophages. The full length cDNA sequence of PaCTSD was 1955 bp encoding a propeptide of 397 amino acids. The deduced protein had a calculated molecular weight of 43.17x 103. Multiple alignment with other known CTSD amino acid sequences revealed amino acid conservation through the teleosts. Phylogenetic tree analysis showed that PaCTSD grouped tightly with other fish CTSD, and was close to that of Atlantic salmon and rainbow trout. Subsequently, PaCTSD was prokaryotically expressed and refolded by the urea gradient method on a nickel-nitrilotriacetic acid column. Enzyme activity analysis showed that PaCTSD exhibited pH-dependent proteolytic activity. Quantitative real-time PCR showed that PaCTSD mRNA was expressed in all detected tissues in healthy sweetfish. The highest expression was observed in the spleen and white blood cells, followed by liver, head-kidney, kidney, intestine, gill, and muscle. After Listonella anguillarum infection, PaCTSD transcripts were up-regulated significantly in liver, spleen, white blood cells, and head-kidney of sweetfish. In summary, PaCTSD has proteolytic activity and is closely involved in the immune response of sweetfish. 展开更多
关键词 Cathepsin D Plecolossus altivelis Bacterial infection Prokaryotic expression QRT-PCR
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Catalytic synthesis of perfluorolyethers 被引量:1
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作者 阳卫军 方超 +2 位作者 周济苍 郭灿城 万伟 《Journal of Central South University》 SCIE EI CAS 2013年第3期629-633,共5页
Perfluorolyether is characterized by highly chemical inertness, oxidative stability, anticorrosion as well as radiation resistance. It can be used as lubricant especially in harsh environmental conditions. In this wor... Perfluorolyether is characterized by highly chemical inertness, oxidative stability, anticorrosion as well as radiation resistance. It can be used as lubricant especially in harsh environmental conditions. In this work, hexafluoropylene oxide was catalytically polymerized at low temperature using the methods of anionic polymerization, and perfluorolyethers were obtained with number-average degree of polymerization more than 15. CsF and RbF were used as catalysts and their catalytic activities were investigated. Experimental results show that perfluorolyethers with number-average molar masses up to 3 000 g/mol could be obtained using the two kinds of catalysts, respectively. As compared to CsF, the number-average degree of polymerization is higher and the relative molecular mass distribution interval is narrower when RbF is used as catalyst. The effect of factors such as impurities' content, reaction temperature and reaction time on the number-average degree of polymerization was also investigated. It is found that low impurities' content and low temperature are beneficial to the generation of high number-average degree of perfluorolyethers. The optimization reaction time is 24 h, and fiarther increase of reaction time does not significantly affect the average relative molecular mass. The product was characterized by IR, 19F NMR and GC-MS, and the catalytic mechanism was analyzed finally. 展开更多
关键词 hexafluoropylene oxide perfluorolyether POLYMERIZATION PURIFICATION
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Lysine-specific Demethylase 1 Represses THP-1 Monocyte-to-macrophage Differentiation
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作者 Rui-feng Yang Guo-wei Zhao +2 位作者 Shu-ting Liang Hou-zao Chen De-pei Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第2期82-87,共6页
Objective To investigate the role of lysine-specific demethylase 1 (LSD1) in the process of THP-1 monocyte-to-macrophage differentiation. Methods Quantitative reverse transcription-polymerase chain reaction (qRT-... Objective To investigate the role of lysine-specific demethylase 1 (LSD1) in the process of THP-1 monocyte-to-macrophage differentiation. Methods Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting were performed to analyze the expression of LSD1 and interleukin-6 (IL-6) in THP-1 monocytes and THP-l-derived macrophages. Chromatin immunoprecipitation (ChiP) assay was applied to detect the occupancy of LSD1 and H3K4 methylation at IL-6 promoter during THP-1 monocyte-to-macrophage differentiation. IL-6 mRNA level and H3K4 methylation at IL-6 promoter were analyzed using qRT-PCR and ChiP assay in LSD 1 -knockdown THP- 1 cells treated with 12-O-tetradecanoylphorbol- 13-acetate (TPA) for 0 4, 8, 12, and 24 hours. Fluorescence activated flow cytometry was performed to reveal the percentage of macrophages differentiated from THP- 1 monocytes. Results The expression of LSD1 reduced during THP-1 monocyte-to-macrophage differentiation (P〈0.01). LSD1 occupancy decreased and H3K4 methylation increased at IL-6 promoter during the differentiation. With knockdown of LSD1, H3K4 methylation at IL-6 promoter was found increased after TPA treatment at different times points (all P〈0.05, except 24 hours). The percentage of macrophages increased significantly in theTHP-I cells with LSD1 knockdown (P〈0.05). Conclusions LSD1 is repressed during the monocyte-to-macrophage differentiation of THP-1 cells. Suppression of LSD 1-mediated H3K4 demethylation may be required for THP-1 monocyte-to-macrophage differentiation. 展开更多
关键词 lysine-specific demethylase 1 INTERLEUKIN-6 H3K4 methylation monocyte-to-macrophage differentiation
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