This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by...This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by normal tensor voting theory,(2)co ntraction of trace feature points,(3)connection of trace feature points,(4)linearization of trace segments,and(5)connection of trace segments.A sensitivity analysis was then conducted to identify the optimal parameters of the proposed method.Three field cases,a natural rock mass outcrop and two excavated rock tunnel surfaces,were analyzed using the proposed method to evaluate its validity and efficiency.The results show that the proposed method is more efficient and accurate than the traditional trace mapping method,and the efficiency enhancement is more robust as the number of feature points increases.展开更多
Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer...Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.展开更多
AIM: To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectromet...AIM: To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectrometry (MALDITOFMS). METHODS: The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the byptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were used to search NCBI, SWISS-PROT and MSDB databases by using Mascot software. RESULTS: PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified. CONCLUSION: The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established. Protein expression profile of SW480 has been obtained. It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis.展开更多
Determining the distribution of alloying elements,particularly lithium,is crucial for a holistic understanding of magnesium-lithium-based alloys.In this work,a bespoke ratio spectrum-imaging method based on electron e...Determining the distribution of alloying elements,particularly lithium,is crucial for a holistic understanding of magnesium-lithium-based alloys.In this work,a bespoke ratio spectrum-imaging method based on electron energy-loss spectroscopy,in combination with time-of-flight secondary ion mass spectrometry,energy-dispersive X-ray spectroscopy and Z-contrast imaging,was applied to an as-rolled LAZ941 alloy(Mg-9Li-4Al-1Zn in wt.%).This was done to characterize the distribution of alloying elements,including the distribution of solute in the magnesium matrix.The applications of different mapping techniques revealed that precipitates with two different morphologies are rich in Li,Al and Zn,compared to their surrounding matrix.Additionally,it was confirmed that theβ-phase of the alloy contains higher Li and lower Mg concentrations when compared to theα-phase.This study demonstrated the effectiveness and accuracy of the ratio spectrum-imaging method for mapping the elemental distribution(including lithium)in a range of Li-containing materials.展开更多
目的:探索胶上蛋白原位酶切、肽质量指纹图(PMF)分析以及数据库检索方法的优化条件,建立适合于亚细胞比较蛋白质组学研究的质谱鉴定策略。方法:从考马斯亮蓝染色的2-DE胶上取下牛血清白蛋白(BSA)标准蛋白进行胶内原位酶切,与基质(CHCA)...目的:探索胶上蛋白原位酶切、肽质量指纹图(PMF)分析以及数据库检索方法的优化条件,建立适合于亚细胞比较蛋白质组学研究的质谱鉴定策略。方法:从考马斯亮蓝染色的2-DE胶上取下牛血清白蛋白(BSA)标准蛋白进行胶内原位酶切,与基质(CHCA)混匀后进行MALDI-TOF MS分析;对来源于人肝细胞癌细胞株QGY-7703线粒体的差异表达的候选蛋白点L9,按照通过BSA标准蛋白优化的条件进行MALDI-TOF质谱鉴定;其肽质量指纹图(PMF)经MS-Fit检索。结果:经数据库检索,BSA的肽质量指纹图(PMF)匹配肽质量数为10/11,序列覆盖率为19%,说明实验条件完全可信。候选蛋白点L9的PMF数据经数据库检索后,排名前两位的蛋白均为OXCT(3-oxoacid CoA transferase 1 precursor),其匹配肽段为9/13,序列覆盖率为24%;且OXCT的理论分子量(56kda),理论等电点(7.1),与胶上L9蛋白的位置相符。故候选蛋白点L9确认为OXCT(3-oxoacid CoA transferase 1 precursor)。结论:本文所确定的鉴定策略适用于线粒体比较蛋白质组学的研究。展开更多
Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report t...Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report the development of superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres with mesoporous structures for highly efficient enrichment of phosphopeptides.We have demonstrated that the mesoporous ZrO_(2) layer dramatically improves the selective enrichment of phosphopeptides.Our approach allows for in-situ elution and sensitive identification of both mono-phosphorylated and multiphosphorylated peptides in MALDI-TOF mass spectrometry,with the detection limit of down to the femtomole range.The target phosphopeptides can reliably be enriched for MS analysis from various complex samples including the spiked protein digests and tumor cell lysates.The Fe_(3)O_(4)@mZrO_(2) coreshell microspheres promise a useful tool for phosphoproteomics by allowing for highly efficient and selective enrichment of the crucial signaling regulators in a low abundance.展开更多
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been combined with immobilized enzyme microreactor for the rapid, sensitive, and accurate tryptic mapping of protein and polypeptides. The t...Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been combined with immobilized enzyme microreactor for the rapid, sensitive, and accurate tryptic mapping of protein and polypeptides. The technique utilizes the trypsin microreactor by immobilized enzyme on the glycidyl methacrylate (GMA)-modified cellulose membrane. The membrane micro-reactor was used for the tryptic mapping of cytochrome C and the results were compared with those obtained by using free trypsin. A significant increase in the overall sensitivity of the process was observed using the membrane microreactor, as well as the elimination of background signals due to the autolysis of the trypsin. Further, membrane microreactor digestions were found to be rapid and convenient.展开更多
In the last decade, mass valuation system is applied in Albania in addition to individual valuation system for real estate valuation. This system is used for compiling the land value map and apartments value map. Due ...In the last decade, mass valuation system is applied in Albania in addition to individual valuation system for real estate valuation. This system is used for compiling the land value map and apartments value map. Due to the lack of experience in the compilation of these maps, the methodology of valuation is based on the experiences of other countries with similar development of real estate market. The mass assessment, which is applied in determining the values for specific purposes, such as expropriation, compensation and taxes for property transfer through the methodology adopted for this aim, is analyzed in the light of the finding of issues that accompany this application. The aim of this research is to highlight the problems to provide the ways of overcoming them in order to approximate the values of map values with market values. The mass appraisal process requires effective valuation models and proper management of resources. Its accuracy depends upon the extent and quality of property data available. Because of this reason, it is recommended the usage of the GIS (geographic information system), an automated system for collection and processing of the data necessary for valuation, as the first point of integration between two process of valuation, individual and mass valuation.展开更多
Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone(THAP)and 2,5-dihydroxybenzoic acid(DHB)as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass...Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone(THAP)and 2,5-dihydroxybenzoic acid(DHB)as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer(MALDI-TOF MS).High quality negative-ion spectra of commercial sialylated glycan were obtained with THAP as matrix.Detection limit of the glycan was less than 0.1 pmol.After methyl esterification of sialic acid(SA)residue,sialylated glycans were detected sensitively in the positive-ion mode using DHB as matrix.Neutral and sialylated glycans from the mixture of asialofetuin and fetuin were methylesterified and simultaneously recognized in one manipulation.Methyl esterification of SA residue offers a convenient and sensitive way to identify the structure of N-linked glycans for glycan profiling.展开更多
Propionibacterium species are mostly environmental bacteria, some being commensal of mammals including humans, and sometimes pathogenic. These bacteria are poorly identified using routine laboratory methods. Recently,...Propionibacterium species are mostly environmental bacteria, some being commensal of mammals including humans, and sometimes pathogenic. These bacteria are poorly identified using routine laboratory methods. Recently, Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) has emerged as a rapid and efficient method to identify bacterial species. We evaluated the use of MALDI-TOF-MS for identification of all validated Propionibacterium species. Only four of the 15 tested reference strains (26.7%) were correctly identified at the species level, and P. acnes, the most common human pathogenic species was not identified. When applying MALDI-TOF-MS to 48 P. acnes strains, only 18.7% were correctly identified, suggesting an intraspecific variability of proteic profiles among Propionibacterium strains. However, by enriching the Bruker database with spectra from five of these strains and re-testing the other 43 strains against this new database, 93.0% were correctly identified. Our study demonstrates that MALDI-TOF-MS may be used for the identification of Propionibacterium isolates but requires a database enrichment in spectra from additional isolates.展开更多
基金supported by the Special Fund for Basic Research on Scientific Instruments of the National Natural Science Foundation of China(Grant No.4182780021)Emeishan-Hanyuan Highway ProgramTaihang Mountain Highway Program。
文摘This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by normal tensor voting theory,(2)co ntraction of trace feature points,(3)connection of trace feature points,(4)linearization of trace segments,and(5)connection of trace segments.A sensitivity analysis was then conducted to identify the optimal parameters of the proposed method.Three field cases,a natural rock mass outcrop and two excavated rock tunnel surfaces,were analyzed using the proposed method to evaluate its validity and efficiency.The results show that the proposed method is more efficient and accurate than the traditional trace mapping method,and the efficiency enhancement is more robust as the number of feature points increases.
基金the National Natural Science Founda-tion of China (No. 70471022)the NSFC / Hong KongResearch Grant Council (No. 70418013)
文摘Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.
基金Supported by the Natural Science Foundation, Y100-573006Doctoral Foundation of Xi'an Jiaotong University, DFXJTU2002-11
文摘AIM: To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectrometry (MALDITOFMS). METHODS: The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the byptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were used to search NCBI, SWISS-PROT and MSDB databases by using Mascot software. RESULTS: PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified. CONCLUSION: The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established. Protein expression profile of SW480 has been obtained. It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis.
基金Australian Research Council(ARC)for the financial support of this work(Grant No.DP190103592)funded by ARC grants LE110100223(FEI F20),LE0454166(FEI Titan3),LE170100118(Thermo Scientific Spectra-φ),and LE200100132(Thermo Scientific Helios)。
文摘Determining the distribution of alloying elements,particularly lithium,is crucial for a holistic understanding of magnesium-lithium-based alloys.In this work,a bespoke ratio spectrum-imaging method based on electron energy-loss spectroscopy,in combination with time-of-flight secondary ion mass spectrometry,energy-dispersive X-ray spectroscopy and Z-contrast imaging,was applied to an as-rolled LAZ941 alloy(Mg-9Li-4Al-1Zn in wt.%).This was done to characterize the distribution of alloying elements,including the distribution of solute in the magnesium matrix.The applications of different mapping techniques revealed that precipitates with two different morphologies are rich in Li,Al and Zn,compared to their surrounding matrix.Additionally,it was confirmed that theβ-phase of the alloy contains higher Li and lower Mg concentrations when compared to theα-phase.This study demonstrated the effectiveness and accuracy of the ratio spectrum-imaging method for mapping the elemental distribution(including lithium)in a range of Li-containing materials.
文摘目的:探索胶上蛋白原位酶切、肽质量指纹图(PMF)分析以及数据库检索方法的优化条件,建立适合于亚细胞比较蛋白质组学研究的质谱鉴定策略。方法:从考马斯亮蓝染色的2-DE胶上取下牛血清白蛋白(BSA)标准蛋白进行胶内原位酶切,与基质(CHCA)混匀后进行MALDI-TOF MS分析;对来源于人肝细胞癌细胞株QGY-7703线粒体的差异表达的候选蛋白点L9,按照通过BSA标准蛋白优化的条件进行MALDI-TOF质谱鉴定;其肽质量指纹图(PMF)经MS-Fit检索。结果:经数据库检索,BSA的肽质量指纹图(PMF)匹配肽质量数为10/11,序列覆盖率为19%,说明实验条件完全可信。候选蛋白点L9的PMF数据经数据库检索后,排名前两位的蛋白均为OXCT(3-oxoacid CoA transferase 1 precursor),其匹配肽段为9/13,序列覆盖率为24%;且OXCT的理论分子量(56kda),理论等电点(7.1),与胶上L9蛋白的位置相符。故候选蛋白点L9确认为OXCT(3-oxoacid CoA transferase 1 precursor)。结论:本文所确定的鉴定策略适用于线粒体比较蛋白质组学的研究。
基金supported by the National Key Research and Development Program of China(2017YFE0131700)and the National Natural Science Foundation of China(21874096)+3 种基金a project supported by Collaborative Innovation Center of Suzhou Nano Science and Technologythe 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devicesthe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report the development of superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres with mesoporous structures for highly efficient enrichment of phosphopeptides.We have demonstrated that the mesoporous ZrO_(2) layer dramatically improves the selective enrichment of phosphopeptides.Our approach allows for in-situ elution and sensitive identification of both mono-phosphorylated and multiphosphorylated peptides in MALDI-TOF mass spectrometry,with the detection limit of down to the femtomole range.The target phosphopeptides can reliably be enriched for MS analysis from various complex samples including the spiked protein digests and tumor cell lysates.The Fe_(3)O_(4)@mZrO_(2) coreshell microspheres promise a useful tool for phosphoproteomics by allowing for highly efficient and selective enrichment of the crucial signaling regulators in a low abundance.
文摘Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been combined with immobilized enzyme microreactor for the rapid, sensitive, and accurate tryptic mapping of protein and polypeptides. The technique utilizes the trypsin microreactor by immobilized enzyme on the glycidyl methacrylate (GMA)-modified cellulose membrane. The membrane micro-reactor was used for the tryptic mapping of cytochrome C and the results were compared with those obtained by using free trypsin. A significant increase in the overall sensitivity of the process was observed using the membrane microreactor, as well as the elimination of background signals due to the autolysis of the trypsin. Further, membrane microreactor digestions were found to be rapid and convenient.
文摘In the last decade, mass valuation system is applied in Albania in addition to individual valuation system for real estate valuation. This system is used for compiling the land value map and apartments value map. Due to the lack of experience in the compilation of these maps, the methodology of valuation is based on the experiences of other countries with similar development of real estate market. The mass assessment, which is applied in determining the values for specific purposes, such as expropriation, compensation and taxes for property transfer through the methodology adopted for this aim, is analyzed in the light of the finding of issues that accompany this application. The aim of this research is to highlight the problems to provide the ways of overcoming them in order to approximate the values of map values with market values. The mass appraisal process requires effective valuation models and proper management of resources. Its accuracy depends upon the extent and quality of property data available. Because of this reason, it is recommended the usage of the GIS (geographic information system), an automated system for collection and processing of the data necessary for valuation, as the first point of integration between two process of valuation, individual and mass valuation.
基金Supported by the National Natural Science Foundation of China(30800193)Grant from Centre for International Mobility(CIMO),Finland
文摘Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone(THAP)and 2,5-dihydroxybenzoic acid(DHB)as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer(MALDI-TOF MS).High quality negative-ion spectra of commercial sialylated glycan were obtained with THAP as matrix.Detection limit of the glycan was less than 0.1 pmol.After methyl esterification of sialic acid(SA)residue,sialylated glycans were detected sensitively in the positive-ion mode using DHB as matrix.Neutral and sialylated glycans from the mixture of asialofetuin and fetuin were methylesterified and simultaneously recognized in one manipulation.Methyl esterification of SA residue offers a convenient and sensitive way to identify the structure of N-linked glycans for glycan profiling.
文摘Propionibacterium species are mostly environmental bacteria, some being commensal of mammals including humans, and sometimes pathogenic. These bacteria are poorly identified using routine laboratory methods. Recently, Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) has emerged as a rapid and efficient method to identify bacterial species. We evaluated the use of MALDI-TOF-MS for identification of all validated Propionibacterium species. Only four of the 15 tested reference strains (26.7%) were correctly identified at the species level, and P. acnes, the most common human pathogenic species was not identified. When applying MALDI-TOF-MS to 48 P. acnes strains, only 18.7% were correctly identified, suggesting an intraspecific variability of proteic profiles among Propionibacterium strains. However, by enriching the Bruker database with spectra from five of these strains and re-testing the other 43 strains against this new database, 93.0% were correctly identified. Our study demonstrates that MALDI-TOF-MS may be used for the identification of Propionibacterium isolates but requires a database enrichment in spectra from additional isolates.