The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Thierry Fouquet - One of the best experts on this subject based on the ideXlab platform.
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graphical ranking of divisors to get the most out of a resolution enhanced kendrick Mass Defect plot
Analytical Chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-p...
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Graphical Ranking of Divisors to Get the Most out of a Resolution-Enhanced Kendrick Mass Defect Plot
Analytical chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-processing tool to unravel complex Mass spectra of polymers. It enhances regular KMD analysis using the chemical moiety, R, to compute Mass Defects with unprecedented separation of ion series differing by their isotopic or comonomeric contents, end-groups, or charge states in highly visual KMD plots. The value of the divisor, X, dictates the gain of separating power from the regular to the resolution-enhanced KMD plot, and its choice strongly affects the ease and speed of data interpretation. A simple tool to help select the best values of X depending on the users’ needs is mandatory to rationalize the analysis and avoid a time-consuming trial-and-error methodology. We propose two graphical representations intuitively ranking the well-suited divisors for the appropriate separation of isotopes or co-oligomers for ...
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"Reverse Kendrick Mass Defect Analysis": Rotating Mass Defect Graphs to Determine Oligomer Compositions for Homopolymers.
Analytical chemistry, 2018Co-Authors: Robert B. Cody, Thierry FouquetAbstract:A new approach to determining the repeat unit compositions of homopolymers is reported in which a Mass Defect graph is rotated to zero slope to give a graph identical to a Kendrick Mass Defect graph. Because the Kendrick Mass Defect (KMD) is directly related to the elemental composition of the base unit, the process can be reversed. A Mass Defect graph (fractional m/z plotted against exact m/z) of a homopolymer can be rotated until the slope of the data points is zero. This is equivalent to finding a new constant factor by which the measured exact Masses would have to be multiplied to create a Kendrick Mass Defect graph with zero slope. The elemental composition of the repeat unit can be determined by matching the new factor against the calculated factors for candidate compositions. This approach provides some benefits over simply looking for pairs of peaks corresponding to oligomer units. The primary benefit is to assist in visualization of the data. Rotating the data points corresponding to polymer Mass...
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Resolution-Enhanced Kendrick Mass Defect Analysis of Polycyclic Aromatic Hydrocarbons and Fullerenes in the Diffusion Flame from a Butane Torch
Journal of the American Society for Mass Spectrometry, 2018Co-Authors: Robert B. Cody, Thierry FouquetAbstract:A modified Kendrick Mass Defect (KMD) analysis was applied to the analysis of polycyclic aromatic hydrocarbons (PAHs) and fullerenes in the diffusion flame from a handheld butane torch. Graphical Abstract ᅟ.
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On the Kendrick Mass Defect Plots of Multiply Charged Polymer Ions: Splits, Misalignments, and How to Correct Them.
Journal of the American Society for Mass Spectrometry, 2018Co-Authors: Thierry Fouquet, Robert B. Cody, Yuka Ozeki, Shinya Kitagawa, Hajime Ohtani, Hiroaki SatoAbstract:The Kendrick Mass Defect (KMD) analysis of multiply charged polymeric distributions has recently revealed a surprising isotopic split in their KMD plots—namely a 1/z difference between KMDs of isotopes of an oligomer at charge state z. Relying on the KMD analysis of actual and simulated distributions of poly(ethylene oxide) (PEO), the isotopic split is mathematically accounted for and found to go with an isotopic misalignment in certain cases. It is demonstrated that the divisibility (resp. indivisibility) of the nominal Mass of the repeating unit (R) by z is the condition for homolog ions to line up horizontally (resp. misaligned obliquely) in a KMD plot. Computing KMDs using a fractional base unit R/z eventually corrects the misalignments for the associated charge state while using the least common multiple of all the charge states as the divisor realigns all the points at once. The isotopic split itself can be removed by using either a new charge-dependent KMD plot compatible with any fractional base unit or the remainders of KM (RKM) recently developed for low-resolution data all found to be linked in a unified theory. These original applications of the fractional base units and the RKM plots are of importance theoretically to satisfy the basics of a Mass Defect analysis and practically for a correct data handling of single stage and tandem Mass spectra of multiply charged homo- and copolymers.
Francisco Melo - One of the best experts on this subject based on the ideXlab platform.
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Wave localization in strongly nonlinear Hertzian chains with Mass Defect
Physical Review E : Statistical Nonlinear and Soft Matter Physics, 2009Co-Authors: Stéphane Job, Francisco Santibanez, Franco Tapia, Francisco MeloAbstract:We investigate the dynamical response of a Mass Defect in a one-dimensional non-loaded horizontal chain of identical spheres which interact via the nonlinear Hertz potential. Our experiments show that the interaction of a solitary wave with a light intruder excites localized mode. In agreement with dimensional analysis, we find that the frequency of localized oscillations exceeds the incident wave frequency spectrum and nonlinearly depends on the size of the intruder and on the incident wave strength. The absence of tensile stress between grains allows some gaps to open, which in turn induce a significant enhancement of the oscillations amplitude. We performed numerical simulations that precisely describe our observations without any adjusting parameters.
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Wave localization in strongly nonlinear Hertzian chains with Mass Defect.
Physical Review E, 2009Co-Authors: Stéphane Job, Francisco Santibanez, Franco Tapia, Francisco MeloAbstract:We report observations of mechanical energy localization in a strongly nonlinear discrete lattice. The experimental setup we consider is a one-dimensional nonloaded horizontal chain of identical spheres interacting via the nonlinear Hertz potential which contains a Mass Defect. Our experiments show that the interaction of a solitary wave with a light intruder excites a nonlinear localized mode. In agreement with dimensional analysis, we find that the frequency of localized oscillations exceeds the incident wave frequency spectrum and nonlinearly depends on incident wave strength and on Mass and size of the intruder. The absence of tensile stress between grains allows some gaps to open, which in turn induces a significant enhancement of the amplitude of oscillations. We performed numerical simulations that precisely describe our observations without any adjusting parameters.
Hiroaki Sato - One of the best experts on this subject based on the ideXlab platform.
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graphical ranking of divisors to get the most out of a resolution enhanced kendrick Mass Defect plot
Analytical Chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-p...
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Graphical Ranking of Divisors to Get the Most out of a Resolution-Enhanced Kendrick Mass Defect Plot
Analytical chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-processing tool to unravel complex Mass spectra of polymers. It enhances regular KMD analysis using the chemical moiety, R, to compute Mass Defects with unprecedented separation of ion series differing by their isotopic or comonomeric contents, end-groups, or charge states in highly visual KMD plots. The value of the divisor, X, dictates the gain of separating power from the regular to the resolution-enhanced KMD plot, and its choice strongly affects the ease and speed of data interpretation. A simple tool to help select the best values of X depending on the users’ needs is mandatory to rationalize the analysis and avoid a time-consuming trial-and-error methodology. We propose two graphical representations intuitively ranking the well-suited divisors for the appropriate separation of isotopes or co-oligomers for ...
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On the Kendrick Mass Defect Plots of Multiply Charged Polymer Ions: Splits, Misalignments, and How to Correct Them.
Journal of the American Society for Mass Spectrometry, 2018Co-Authors: Thierry Fouquet, Robert B. Cody, Yuka Ozeki, Shinya Kitagawa, Hajime Ohtani, Hiroaki SatoAbstract:The Kendrick Mass Defect (KMD) analysis of multiply charged polymeric distributions has recently revealed a surprising isotopic split in their KMD plots—namely a 1/z difference between KMDs of isotopes of an oligomer at charge state z. Relying on the KMD analysis of actual and simulated distributions of poly(ethylene oxide) (PEO), the isotopic split is mathematically accounted for and found to go with an isotopic misalignment in certain cases. It is demonstrated that the divisibility (resp. indivisibility) of the nominal Mass of the repeating unit (R) by z is the condition for homolog ions to line up horizontally (resp. misaligned obliquely) in a KMD plot. Computing KMDs using a fractional base unit R/z eventually corrects the misalignments for the associated charge state while using the least common multiple of all the charge states as the divisor realigns all the points at once. The isotopic split itself can be removed by using either a new charge-dependent KMD plot compatible with any fractional base unit or the remainders of KM (RKM) recently developed for low-resolution data all found to be linked in a unified theory. These original applications of the fractional base units and the RKM plots are of importance theoretically to satisfy the basics of a Mass Defect analysis and practically for a correct data handling of single stage and tandem Mass spectra of multiply charged homo- and copolymers.
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Convenient Graphical Visualization of Messages Encoded in Sequence-Defined Synthetic Polymers Using Kendrick Mass Defect Analysis of their MS/MS Data
Macromolecular Chemistry and Physics, 2018Co-Authors: Salomé Poyer, Thierry Fouquet, Hiroaki Sato, Jean-francois Lutz, Laurence CharlesAbstract:Kendrick Mass Defect (KMD) analysis is shown here to be a convenient method to read binary messages encoded in the structure of two types of sequence-defined synthetic polymers, namely, polyurethanes and poly(alkoxyamine phosphodiester)s. KMD analysis allows graphical ranking of Mass data obtained for species containing repeating units. This is performed on MS/MS data in which distribution of fragments reveals the comonomer sequence of digital macromolecules. Choosing one coding monomer as the base unit, KMD computation of MS/MS data leads to stair-like plots where flat steps correspond to that monomer selected as the base unit while oblique steps reveal the other monomer. To correct for any point misalignments resulting from slight inaccuracy of fragment Mass measurement, fractional base units are used to perform resolution-enhanced KMD (RE-KMD) analysis. As the length of the chain increased, a procedure aiming at correct aliased points is also implemented to achieve continuous, more convenient, stair-like plots.
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improving the resolution of kendrick Mass Defect analysis for polymer ions with fractional base units
Mass spectrometry, 2017Co-Authors: Thierry Fouquet, Hiroaki SatoAbstract:The concept of a fractional base unit for the Kendrick Mass Defect (KMD) analysis of polymer ions is introduced for the first time. A fraction of the ethylene oxide (EO) repeat unit (namely EO/8) has been used for the KMD analysis of a poly(ethylene oxide) and found to amplify the variations of KMD between monoisotopic and 13C isotopes, producing an isotopically resolved KMD plot at full scale when the KMD plot computed with EO is fuzzy. The expansion of the KMD dimension using a fractional base unit has then been successfully used to unequivocally discriminate all the distributions from a blend of poly(ethylene oxide)s in a high resolution KMD plot calculated with EO/3 as base unit. Extending the concept of fractional base units to other repeat units, the visualization of the co-oligomers from a poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) triblock copolymer has been dramatically improved using a fraction of the propylene oxide repeat unit (namely PO/3) in an oligomer and isotope resolved plot. High resolution KMD plots were eventually calculated from tandem Mass spectra of poly(dimethylsiloxane) ions using a fraction of the dimethylsiloxane (DMS) unit (namely DMS/6) with clearer point alignments and a discrimination of all the product ion series, out of reach of the KMD analysis using DMS. Versatile and producing high resolution KMD plots, the introduction of fractional base units is believed to be a major step towards the implementation of the KMD analysis as a routine data mining tool for Mass spectrometry in polymer chemistry.
Pei Chen - One of the best experts on this subject based on the ideXlab platform.
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comprehensive characterization of c glycosyl flavones in wheat triticum aestivum l germ using uplc pda esi hrmsn and Mass Defect filtering
Journal of Mass Spectrometry, 2016Co-Authors: Ping Geng, Mengliang Zhang, Jianghao Sun, James M Harnly, Pei ChenAbstract:A comprehensive characterization of C-glycosyl flavones in wheat germ has been conducted using multi-stage high resolution Mass spectrometry (HRMSn ) in combination with a Mass Defect filtering (MDF) technique. MDF performed the initial search of raw data with defined C-glycosyl flavone Mass windows and Mass Defect windows to generate the noise-reduced data focusing on targeted flavonoids. The high specificity of the exact Mass measurement permits the unambiguous discrimination of acyl groups (nominal Masses of 146, 162 and 176.) from sugar moieties (rhamnose, glucose or galactose and glucuronic acid). A total of 72 flavone C-glycosyl derivatives, including 2 mono-C-glycosides, 34 di-C-glycosides, 15 tri-glycosides, 14 acyl di-C-glycosides and 7 acyl tri-glycosides, were characterized in wheat germ, some of which were considered to be important marker compounds for differentiation of whole grain and refined wheat products. The 7 acylated mono-O-glycosyl-di-C-glycosyl flavones and some acylated di-C-glycosyl flavones are reported in wheat for the first time. The frequent occurrence of numerous isomers is a remarkable feature of wheat germ flavones. Both UV and Mass spectra are needed to maximize the structure information obtained for data interpretation. Copyright © 2016 John Wiley & Sons, Ltd.
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Comprehensive characterization of C‐glycosyl flavones in wheat (Triticum aestivum L.) germ using UPLC‐PDA‐ESI/HRMSn and Mass Defect filtering
Journal of mass spectrometry : JMS, 2016Co-Authors: Ping Geng, Mengliang Zhang, Jianghao Sun, James M Harnly, Pei ChenAbstract:A comprehensive characterization of C-glycosyl flavones in wheat germ has been conducted using multi-stage high resolution Mass spectrometry (HRMSn ) in combination with a Mass Defect filtering (MDF) technique. MDF performed the initial search of raw data with defined C-glycosyl flavone Mass windows and Mass Defect windows to generate the noise-reduced data focusing on targeted flavonoids. The high specificity of the exact Mass measurement permits the unambiguous discrimination of acyl groups (nominal Masses of 146, 162 and 176.) from sugar moieties (rhamnose, glucose or galactose and glucuronic acid). A total of 72 flavone C-glycosyl derivatives, including 2 mono-C-glycosides, 34 di-C-glycosides, 15 tri-glycosides, 14 acyl di-C-glycosides and 7 acyl tri-glycosides, were characterized in wheat germ, some of which were considered to be important marker compounds for differentiation of whole grain and refined wheat products. The 7 acylated mono-O-glycosyl-di-C-glycosyl flavones and some acylated di-C-glycosyl flavones are reported in wheat for the first time. The frequent occurrence of numerous isomers is a remarkable feature of wheat germ flavones. Both UV and Mass spectra are needed to maximize the structure information obtained for data interpretation. Copyright © 2016 John Wiley & Sons, Ltd.
Robert B. Cody - One of the best experts on this subject based on the ideXlab platform.
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graphical ranking of divisors to get the most out of a resolution enhanced kendrick Mass Defect plot
Analytical Chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-p...
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Graphical Ranking of Divisors to Get the Most out of a Resolution-Enhanced Kendrick Mass Defect Plot
Analytical chemistry, 2019Co-Authors: Sayaka Nakamura, Robert B. Cody, Hiroaki Sato, Thierry FouquetAbstract:Resolution-enhanced Kendrick Mass Defect (KMD) analysis using the new concept of fractional base units (repeating unit R divided by integer X; R/X as a mathematical moiety) is now a powerful data-processing tool to unravel complex Mass spectra of polymers. It enhances regular KMD analysis using the chemical moiety, R, to compute Mass Defects with unprecedented separation of ion series differing by their isotopic or comonomeric contents, end-groups, or charge states in highly visual KMD plots. The value of the divisor, X, dictates the gain of separating power from the regular to the resolution-enhanced KMD plot, and its choice strongly affects the ease and speed of data interpretation. A simple tool to help select the best values of X depending on the users’ needs is mandatory to rationalize the analysis and avoid a time-consuming trial-and-error methodology. We propose two graphical representations intuitively ranking the well-suited divisors for the appropriate separation of isotopes or co-oligomers for ...
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"Reverse Kendrick Mass Defect Analysis": Rotating Mass Defect Graphs to Determine Oligomer Compositions for Homopolymers.
Analytical chemistry, 2018Co-Authors: Robert B. Cody, Thierry FouquetAbstract:A new approach to determining the repeat unit compositions of homopolymers is reported in which a Mass Defect graph is rotated to zero slope to give a graph identical to a Kendrick Mass Defect graph. Because the Kendrick Mass Defect (KMD) is directly related to the elemental composition of the base unit, the process can be reversed. A Mass Defect graph (fractional m/z plotted against exact m/z) of a homopolymer can be rotated until the slope of the data points is zero. This is equivalent to finding a new constant factor by which the measured exact Masses would have to be multiplied to create a Kendrick Mass Defect graph with zero slope. The elemental composition of the repeat unit can be determined by matching the new factor against the calculated factors for candidate compositions. This approach provides some benefits over simply looking for pairs of peaks corresponding to oligomer units. The primary benefit is to assist in visualization of the data. Rotating the data points corresponding to polymer Mass...
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Resolution-Enhanced Kendrick Mass Defect Analysis of Polycyclic Aromatic Hydrocarbons and Fullerenes in the Diffusion Flame from a Butane Torch
Journal of the American Society for Mass Spectrometry, 2018Co-Authors: Robert B. Cody, Thierry FouquetAbstract:A modified Kendrick Mass Defect (KMD) analysis was applied to the analysis of polycyclic aromatic hydrocarbons (PAHs) and fullerenes in the diffusion flame from a handheld butane torch. Graphical Abstract ᅟ.
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On the Kendrick Mass Defect Plots of Multiply Charged Polymer Ions: Splits, Misalignments, and How to Correct Them.
Journal of the American Society for Mass Spectrometry, 2018Co-Authors: Thierry Fouquet, Robert B. Cody, Yuka Ozeki, Shinya Kitagawa, Hajime Ohtani, Hiroaki SatoAbstract:The Kendrick Mass Defect (KMD) analysis of multiply charged polymeric distributions has recently revealed a surprising isotopic split in their KMD plots—namely a 1/z difference between KMDs of isotopes of an oligomer at charge state z. Relying on the KMD analysis of actual and simulated distributions of poly(ethylene oxide) (PEO), the isotopic split is mathematically accounted for and found to go with an isotopic misalignment in certain cases. It is demonstrated that the divisibility (resp. indivisibility) of the nominal Mass of the repeating unit (R) by z is the condition for homolog ions to line up horizontally (resp. misaligned obliquely) in a KMD plot. Computing KMDs using a fractional base unit R/z eventually corrects the misalignments for the associated charge state while using the least common multiple of all the charge states as the divisor realigns all the points at once. The isotopic split itself can be removed by using either a new charge-dependent KMD plot compatible with any fractional base unit or the remainders of KM (RKM) recently developed for low-resolution data all found to be linked in a unified theory. These original applications of the fractional base units and the RKM plots are of importance theoretically to satisfy the basics of a Mass Defect analysis and practically for a correct data handling of single stage and tandem Mass spectra of multiply charged homo- and copolymers.