We study constraints on neutrino properties for a class of bi-large mixing See-Saw mass matrices with texture zeros and with the related Dirac neutrino mass matrix to be proportional to a diagonal matrix of the form d...We study constraints on neutrino properties for a class of bi-large mixing See-Saw mass matrices with texture zeros and with the related Dirac neutrino mass matrix to be proportional to a diagonal matrix of the form diag （e, 1, 1）. Texture zeros may occur in the light （class a）） or in the heavy （class b）） neutrino mass matrices. Each of these two classes has 5 different forms which can produce non-trivial three generation mixing with at least one texture zero. We tind that two types of texture zero mass matrices in both class a and class b can be consistent with present data on neutrino masses and mixing. None of the neutrinos can have zero masses and the lightest of the light neutrinos has a mass larger than about 0.046 eV for class a and 0.0027 eV for class b. In these models although the CK.M CP violating phase vanishes, the non-zero Majorana phases can exist and can play an important role in producing the observed baryon asymmetry in our universe through leptogenesis mechanism. The requirement of producing the observed baryon asymmetry can further distinguish different models and also restrict the See-Saw scale to be in the range of 10^12- 10^15 GeV. We also discuss RG effects on V^13.展开更多
The actual value of Higgs boson mass is difficult to determine theoretically due to lack of knowledge on the exact value of Higgs self coupling constant l. The purpose of this paper is to obtain an upper bound on the ...The actual value of Higgs boson mass is difficult to determine theoretically due to lack of knowledge on the exact value of Higgs self coupling constant l. The purpose of this paper is to obtain an upper bound on the Higgs mass in the Standard Model on the basis of one-loop effective potential in the ’t Hooft-Landau gauge and MS scheme. The condition of positivity of mass matrix at ф?= ф0 (where ф0 is the absolute minimum of the effective potential) of the scalar field gives an upper bound on the Higgs self coupling as l ≤ 0.881. This condition yields an upper bound on the Higgs mass as mH ≤ 229.48 GeV.展开更多
The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residua...The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residual symmetry. We offer an intuitive display of the structure of the Majorana neutrino mass matrix, using the whole set of the oscillation data. The structure is revealed depending on the lightest neutrino mass. We find that there are three regions with distinct characteristics of structure. A group effect and the μ-T exchange symmetry are observed. Six types of texture non-zeros are shown. Implications for flavor models are discussed.展开更多
The fault element is used to handle soft clay strata in a rock mass.The formulas or clasto-plastic stiffnessmatrix for the fault element are derived using the constitutive relationship between plastic increment stress...The fault element is used to handle soft clay strata in a rock mass.The formulas or clasto-plastic stiffnessmatrix for the fault element are derived using the constitutive relationship between plastic increment stress andstrain.A numerical example of a circular tunnel with soft clay strata in the rock medium are examined.展开更多
Introduction Single nucleotide polymorphisms （SNPs） are the most abundant DNA markers in the human genome occurring at a frequency of one in every 500--1000 nucleotides. A variety of methods have been used for the ...Introduction Single nucleotide polymorphisms （SNPs） are the most abundant DNA markers in the human genome occurring at a frequency of one in every 500--1000 nucleotides. A variety of methods have been used for the analysis of single nucleotide polymorphisms, including restriction fragment length polymorphism （RFLP）, direct sequencing by using laser-induced fluorescence detectionTM, fluorescence energy transfer, MALDI-TOF MS combined with primer extension or invasive cleavage, and fluorescence polarization. During the past two decades, mass spectrometry has become a very popular tool in the analysis of biomolecules and is perfectly suited to the analysis of single nucleotide polymorphisms （SNPs） due to its speed, low cost, and accuracy. In this work, we used MALDI TOF mass spectrometry to detect the fragments of restriction endonuclease hydrolysis of PCR products flanking a SNP located at paraoxonase 1（Q192R）. Compared with electrophoresis, this method requires less time of analysis and possess a higher accuracy.展开更多
Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in si...Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in sick children is very challenging for clinicians who frequently rely on indices such as long capillary refill times, tachycardia, central venous pressure and decreased urine volume as guides. Here, we present the UHAS-MIDA, an open-source software tool that calculates the red blood cell (RBC) concentration and blood volume during malaria in children determined using a stable isotope of chromium (<sup>53</sup>Cr as the label) by gas chromatography-mass spectrometry in selective ion monitoring (GC/MS-SIM) analysis. A key component involves the determination of the compositions of the most abundant naturally occurring isotopes of Cr (<sup>50</sup>Cr, <sup>52</sup>Cr, <sup>53</sup>Cr), and converting the proportions into a 3 × 3 matrix. To estimate unknown proportions of chromium isotopic mixtures from the measured abundances of three ions, an inverse matrix was calculated. The inverse together with several inputs is then used to calculate the corrected MS ion abundances. Thus, we constructed the software tool UHAS- MIDA using HTML, CSS/Bootstrap, JavaScript, and PHP scripting languages. The tool enables the user to efficiently determine RBC concentration and fluid volume. The source code, binary packages and associated materials for UHAS-MIDA are freely available at https://github.com/bentil078/Abaye-et-al_UHASmida展开更多
In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis...In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis, other alternatives must be employed. Traditionally, the method of standard additions is used to correct the matrix effect but it is a time consuming method. Others methods involves separation techniques. Another way to overcome matrix interferences is to understand the mechanism involved and adjust plasma viewing conditions to reduce or eliminate the effect. In this study, the effect of various concomitant elements in ICP-MS was assessed by measuring the distribution of selected singly charged analyte ions (Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, In, Ba, La, Ce, Pb), doubly charged ions (La, Ce, Ba and Pb) and oxides ions (BaO) in the presence of concomitant elements spanning a mass range from 23 (Na) to 133 (Cs) u.m.a. and different ionization energies. Concomitant elements are alkali metals, alkaline earth metals and Si. Analyte ion suppression was observed while moving the ICP across and away from the sampling interface with or without a single concomitant element. Matrix effect measures were realised, firstly, to highlight the relation between the signal extinction of an analyte and the masse of the concomitant element, and secondly to highlight the relation between the removal of the analyte signal and the first ionization energy of the element of matrix. A dependence upon both the mass of the matrix element and the mass of the analyte was observed. The suppression seems increased with increasing matrix element mass and decreased with increasing analyte mass. The effect of the mass of the matrix element was the more significant of the two factors. If space-charge effects were found to be significant for matrix elements of much lower mass, it seems diffusion also played an active part for heavier matrix elements. Finally, some evidence was found for a shift in ion-atom equilibrium for dications and for energy demand regarding oxides.展开更多
A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and sign...A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and signal intensity of mass spectra were improved. The mechanism was also analyzed.展开更多
The aim of this theoretical investigation is the description of the multicomponent mass transfer process in the Nano- Composites (NC)—novel materials with the bi-functional matrix. The new theoretical NC Model is ass...The aim of this theoretical investigation is the description of the multicomponent mass transfer process in the Nano- Composites (NC)—novel materials with the bi-functional matrix. The new theoretical NC Model is assigned for the modern theoretical investigations of the multicomponent mass transfer kinetics in the bi-functional NC materials. This NC Model for the multicomponent mass transfer in the bi-functional NC matrix includes into the consideration the proposed key conception—two co-existing routes: I—chemical reactions onto the active NC centers-sites, and II—diffusion mass transfer inside the bi-functional NC matrix. All the results are presented in the terms of the additional key concept: propagating multicomponent concentration waves (W+) in the NC matrix. The used W+ concept for the description of the multicomponent NC mass transfer kinetics give the clear interpretation of the computerized results. The mass transfer process in the NC matrix has been described theoretically by computerized simulation. The results of the calculations are new and illustrated by author’s animations showing visually the propagation of the multicomponent concentration waves (W) inside the various NC matrixes: r-beads, cylindrical ro-fibers, or planar L-membranes. Two variants of modeling for mass transfer diffusion kinetics in the bi-functional NC matrixes with one (Variant 1), or two (Variant 2) dissociation-association reactions at the active nano-sites (R0) are considered theoretically.展开更多
Matrix-assisted Laser Desorption/Ionization with Time-of-flight Mass Spectrometry (MALDI-TOFMS) was investigated as a method for the rapid identifica-tion of species. Current demand in microbial identi-fication is how...Matrix-assisted Laser Desorption/Ionization with Time-of-flight Mass Spectrometry (MALDI-TOFMS) was investigated as a method for the rapid identifica-tion of species. Current demand in microbial identi-fication is how to compare unknown strains to the known one quickly, semi-automatically and accurately. In this paper, we present a software tool that allows flexibly microbial matching in a user-friendly way, by letting the users to customize comparison parameters including: in vitro transcription enzyme, mass tolerance,minimum fragment length, intensity threshold and corresponding weights. We provide three spectral scoring functions to compute the affin-ity between the species. Therefore, the precision of microbial comparison increases. To test and verify this tool, we employed experimental spectral data based on MALDI-TOFMS and the gene sequences of E.coli and Salmonella. This software is written in Java for cross-platform intention.展开更多
Identification and quantification of low abundance growth factors and regulators in complex biological samples still present a challenging task in analytical biochemistry. Immunoassays are often used for such purpose ...Identification and quantification of low abundance growth factors and regulators in complex biological samples still present a challenging task in analytical biochemistry. Immunoassays are often used for such purpose but immunoassays face limitation of both availability and qualities of antibody reagents that are necessary for development of immune assays. With genomics data base available, mass spectrometry (MS) can analyze protein tryptic peptides directly for quantitative determination of proteins. In this study, we report a method for detection of matrix metalloproteinase 1 (MMP1), an important extracellular matrix modulator, in human breast cancer cells by quadrupole time-of-flight (Q-TOF) MS. Absolute quantification of MMP1 was conducted using the selected reaction monitoring (SRM) on a triple quadrupole (Triple-Quad) MS via transitions selected from MMP1 tryptic peptides using non isotope labeled MMP1 protein as a titration standard. In comparison with immune based assay, this MS method showed picogram level sensitivity for quantitative determination of MMP1 intotal cell lysates. Our results demonstrated the feasibility of absolute quantification of low abundance proteins using label-free protein standard by mass spectrometry. Therefore, this method provides not only advantages of high sensitivity but also cost saving in comparison with the commonly used mass spectrometry that currently employs isotype labeled proteins for quantitative analysis.展开更多
基金＊The project partly supported by the Special Scientific Research Foundation for Ph. D. Program of Universities of China, National Natural Science Foundation of China
文摘We study constraints on neutrino properties for a class of bi-large mixing See-Saw mass matrices with texture zeros and with the related Dirac neutrino mass matrix to be proportional to a diagonal matrix of the form diag （e, 1, 1）. Texture zeros may occur in the light （class a）） or in the heavy （class b）） neutrino mass matrices. Each of these two classes has 5 different forms which can produce non-trivial three generation mixing with at least one texture zero. We tind that two types of texture zero mass matrices in both class a and class b can be consistent with present data on neutrino masses and mixing. None of the neutrinos can have zero masses and the lightest of the light neutrinos has a mass larger than about 0.046 eV for class a and 0.0027 eV for class b. In these models although the CK.M CP violating phase vanishes, the non-zero Majorana phases can exist and can play an important role in producing the observed baryon asymmetry in our universe through leptogenesis mechanism. The requirement of producing the observed baryon asymmetry can further distinguish different models and also restrict the See-Saw scale to be in the range of 10^12- 10^15 GeV. We also discuss RG effects on V^13.
文摘The actual value of Higgs boson mass is difficult to determine theoretically due to lack of knowledge on the exact value of Higgs self coupling constant l. The purpose of this paper is to obtain an upper bound on the Higgs mass in the Standard Model on the basis of one-loop effective potential in the ’t Hooft-Landau gauge and MS scheme. The condition of positivity of mass matrix at ф?= ф0 (where ф0 is the absolute minimum of the effective potential) of the scalar field gives an upper bound on the Higgs self coupling as l ≤ 0.881. This condition yields an upper bound on the Higgs mass as mH ≤ 229.48 GeV.
基金supported by the National Natural Science Foundation of China(Grant Nos.11035003 and 11120101004)
文摘The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residual symmetry. We offer an intuitive display of the structure of the Majorana neutrino mass matrix, using the whole set of the oscillation data. The structure is revealed depending on the lightest neutrino mass. We find that there are three regions with distinct characteristics of structure. A group effect and the μ-T exchange symmetry are observed. Six types of texture non-zeros are shown. Implications for flavor models are discussed.
基金Project Supported by the National Natural science Foundation of China
文摘The fault element is used to handle soft clay strata in a rock mass.The formulas or clasto-plastic stiffnessmatrix for the fault element are derived using the constitutive relationship between plastic increment stress andstrain.A numerical example of a circular tunnel with soft clay strata in the rock medium are examined.
文摘Introduction Single nucleotide polymorphisms （SNPs） are the most abundant DNA markers in the human genome occurring at a frequency of one in every 500--1000 nucleotides. A variety of methods have been used for the analysis of single nucleotide polymorphisms, including restriction fragment length polymorphism （RFLP）, direct sequencing by using laser-induced fluorescence detectionTM, fluorescence energy transfer, MALDI-TOF MS combined with primer extension or invasive cleavage, and fluorescence polarization. During the past two decades, mass spectrometry has become a very popular tool in the analysis of biomolecules and is perfectly suited to the analysis of single nucleotide polymorphisms （SNPs） due to its speed, low cost, and accuracy. In this work, we used MALDI TOF mass spectrometry to detect the fragments of restriction endonuclease hydrolysis of PCR products flanking a SNP located at paraoxonase 1（Q192R）. Compared with electrophoresis, this method requires less time of analysis and possess a higher accuracy.
文摘Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in sick children is very challenging for clinicians who frequently rely on indices such as long capillary refill times, tachycardia, central venous pressure and decreased urine volume as guides. Here, we present the UHAS-MIDA, an open-source software tool that calculates the red blood cell (RBC) concentration and blood volume during malaria in children determined using a stable isotope of chromium (<sup>53</sup>Cr as the label) by gas chromatography-mass spectrometry in selective ion monitoring (GC/MS-SIM) analysis. A key component involves the determination of the compositions of the most abundant naturally occurring isotopes of Cr (<sup>50</sup>Cr, <sup>52</sup>Cr, <sup>53</sup>Cr), and converting the proportions into a 3 × 3 matrix. To estimate unknown proportions of chromium isotopic mixtures from the measured abundances of three ions, an inverse matrix was calculated. The inverse together with several inputs is then used to calculate the corrected MS ion abundances. Thus, we constructed the software tool UHAS- MIDA using HTML, CSS/Bootstrap, JavaScript, and PHP scripting languages. The tool enables the user to efficiently determine RBC concentration and fluid volume. The source code, binary packages and associated materials for UHAS-MIDA are freely available at https://github.com/bentil078/Abaye-et-al_UHASmida
文摘In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis, other alternatives must be employed. Traditionally, the method of standard additions is used to correct the matrix effect but it is a time consuming method. Others methods involves separation techniques. Another way to overcome matrix interferences is to understand the mechanism involved and adjust plasma viewing conditions to reduce or eliminate the effect. In this study, the effect of various concomitant elements in ICP-MS was assessed by measuring the distribution of selected singly charged analyte ions (Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, In, Ba, La, Ce, Pb), doubly charged ions (La, Ce, Ba and Pb) and oxides ions (BaO) in the presence of concomitant elements spanning a mass range from 23 (Na) to 133 (Cs) u.m.a. and different ionization energies. Concomitant elements are alkali metals, alkaline earth metals and Si. Analyte ion suppression was observed while moving the ICP across and away from the sampling interface with or without a single concomitant element. Matrix effect measures were realised, firstly, to highlight the relation between the signal extinction of an analyte and the masse of the concomitant element, and secondly to highlight the relation between the removal of the analyte signal and the first ionization energy of the element of matrix. A dependence upon both the mass of the matrix element and the mass of the analyte was observed. The suppression seems increased with increasing matrix element mass and decreased with increasing analyte mass. The effect of the mass of the matrix element was the more significant of the two factors. If space-charge effects were found to be significant for matrix elements of much lower mass, it seems diffusion also played an active part for heavier matrix elements. Finally, some evidence was found for a shift in ion-atom equilibrium for dications and for energy demand regarding oxides.
文摘A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and signal intensity of mass spectra were improved. The mechanism was also analyzed.
文摘The aim of this theoretical investigation is the description of the multicomponent mass transfer process in the Nano- Composites (NC)—novel materials with the bi-functional matrix. The new theoretical NC Model is assigned for the modern theoretical investigations of the multicomponent mass transfer kinetics in the bi-functional NC materials. This NC Model for the multicomponent mass transfer in the bi-functional NC matrix includes into the consideration the proposed key conception—two co-existing routes: I—chemical reactions onto the active NC centers-sites, and II—diffusion mass transfer inside the bi-functional NC matrix. All the results are presented in the terms of the additional key concept: propagating multicomponent concentration waves (W+) in the NC matrix. The used W+ concept for the description of the multicomponent NC mass transfer kinetics give the clear interpretation of the computerized results. The mass transfer process in the NC matrix has been described theoretically by computerized simulation. The results of the calculations are new and illustrated by author’s animations showing visually the propagation of the multicomponent concentration waves (W) inside the various NC matrixes: r-beads, cylindrical ro-fibers, or planar L-membranes. Two variants of modeling for mass transfer diffusion kinetics in the bi-functional NC matrixes with one (Variant 1), or two (Variant 2) dissociation-association reactions at the active nano-sites (R0) are considered theoretically.
文摘Matrix-assisted Laser Desorption/Ionization with Time-of-flight Mass Spectrometry (MALDI-TOFMS) was investigated as a method for the rapid identifica-tion of species. Current demand in microbial identi-fication is how to compare unknown strains to the known one quickly, semi-automatically and accurately. In this paper, we present a software tool that allows flexibly microbial matching in a user-friendly way, by letting the users to customize comparison parameters including: in vitro transcription enzyme, mass tolerance,minimum fragment length, intensity threshold and corresponding weights. We provide three spectral scoring functions to compute the affin-ity between the species. Therefore, the precision of microbial comparison increases. To test and verify this tool, we employed experimental spectral data based on MALDI-TOFMS and the gene sequences of E.coli and Salmonella. This software is written in Java for cross-platform intention.
文摘Identification and quantification of low abundance growth factors and regulators in complex biological samples still present a challenging task in analytical biochemistry. Immunoassays are often used for such purpose but immunoassays face limitation of both availability and qualities of antibody reagents that are necessary for development of immune assays. With genomics data base available, mass spectrometry (MS) can analyze protein tryptic peptides directly for quantitative determination of proteins. In this study, we report a method for detection of matrix metalloproteinase 1 (MMP1), an important extracellular matrix modulator, in human breast cancer cells by quadrupole time-of-flight (Q-TOF) MS. Absolute quantification of MMP1 was conducted using the selected reaction monitoring (SRM) on a triple quadrupole (Triple-Quad) MS via transitions selected from MMP1 tryptic peptides using non isotope labeled MMP1 protein as a titration standard. In comparison with immune based assay, this MS method showed picogram level sensitivity for quantitative determination of MMP1 intotal cell lysates. Our results demonstrated the feasibility of absolute quantification of low abundance proteins using label-free protein standard by mass spectrometry. Therefore, this method provides not only advantages of high sensitivity but also cost saving in comparison with the commonly used mass spectrometry that currently employs isotype labeled proteins for quantitative analysis.
