Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 44 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 41-44).

No description available.

Imaging mass spectrometry (IMS) in microscope mode allows the spatially resolved molecular constitution of a large sample section to be analysed in a single experiment. If performed in a linear mass spectrometer, the applicability of microscope IMS is limited by a number of factors: the low mass resolving power of the employed ion optics; the time resolution afforded by the scintillator screen based particle detector and the multi-hit capability, per pixel, of the employed imaging sensor. To overcome these limitations, this thesis concerns the construction of an advanced ion optic employing a pulsed extraction method to gain a higher ToF resolution, the development of a bright scintillator screen with short emission lifetime, and the application of the Pixel Imaging Mass Spectrometry (PImMS) sensor with multi-mass imaging and time stamping capabilities. Initial experimental results employing a three electrode ion optic to spatially map ions emitted from a sample surface are presented. By applying a static electric potential a time-of-flight resolution of t/2Δt=54 and a spatial resolution of 20 μm are determined across a field-of-view of 4 mm diameter. While the moderate time-of-flight resolution only allows particles separated by a few Dalton to be distinguished, the instrument is used to demonstrate the multi-mass imaging capabilities of the PImMS sensor when being applied to image grid structures or tissue samples. An improved time-of-flight resolution is achieved by post extraction differential acceleration of a selected range of ions (up to 100 Da) using a newly developed five electrode ion optic. This modification is shown to correct the initial velocity spread of the ions coming off the sample surface, which yields an enhanced time-of-flight resolution of t/2Δt=2000 . The spatial resolution of the instrument is found to be 20 μm across a field-of-view of 4 mm. Adjusting the extraction field strength applied to the ion optic of the constructed mass spectrometer allows the optimised mass range to be tuned to any mass of interest. Ion images are recorded for various samples with comparable spatial and ToF resolution. Hence, studies on tissue sections and multi sample arrays become accessible with the improved design and operational principle of the microscope mode IMS instrument. A fast and efficient conversion of impinging ions into detectable flashes of light, which can consequently be recorded by a fast imaging sensor, is essential to maintain the achievable time-of-flight and spatial resolution of the IMS instrument constructed. In order to find a suitable fast and bright scintillator to be applied in a microchannel based particle detector, various inorganic and organic substances are characterised in terms of their emission properties following electron excitation. Poly-para-phenylene laser dye screens are found to show an outstanding performance among all substances analysed. An emission life time of below 4 ns and a brightness exceeding that of a P47 screen (industry standard) by a factor 2× is determined. No signal degradation is observed over an extended period, and the spatial resolution is found to be comparable to commercial imaging detectors. Hence, these scintillator screens are fully compatible with any ion imaging application requiring a high time resolution. In a further series of mass spectrometric experiments, ions are accelerated onto a scintillator mounted in front of a multi pixel photon counter. The charged particle impact stimulated the emission of a few photons, which are collected by the fast photon counter. Poly-para-phenylene laser dyes again show an outstanding efficiency for the conversion of ions into photons, resulting in a signal enhancement of up to 5× in comparison to previous experiments, which employed an inorganic LYSO scintillator.

Thesis (Ph.D.)--Ohio University, November, 2007. / Release of full electronic text on OhioLINK has been delayed until November 30, 2008 Includes bibliographical references (leaves 147-164)

Thesis (Ph.D.)--Ohio University, November, 2007. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until November 30, 2008 Includes bibliographical references (leaves 147-164)

Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xiv, 118 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

Resumo: O presente estudo teve como objetivos: 1) Estabelecer possíveis correlações entre as técnicas de força de cisalhamento e o índice de fragmentação miofibrilar para analise da maciez da carne 2) Identificar as proteínas miofibrilares do músculo Longíssimus dorsi de bovinos de corte, associado à maciez da carne; 3) Estudar o efeito da raça, idade do abate e tempo de maturação, sobre a força de cisalhamento, o índice de fragmentação miofibrilar e as proteínas Miofibrilares. Foram utilizados 30 animais da raça Nelore e 30 animais ½ Nelore ½ Aberdeen Angus, criados no modelo biológico Superprecoce abatios nas idades de 12 meses, e de rebanhos comerciais abatidos com 24 meses de idade. As amostras foram submetidas à análise da força de cisalhamento em um Warner-Bratzler Shear Force mecânico e a determinação do MFI. A separação das proteínas foi realizada em eletroforese 1D. Para avaliar os efeitos de grupos genéticos, período de maturação e de idade ao abate sobre a Força de cisalhamento, Índice de fragmentação miofibrilar e intensidade das bandas proteícas, foi utilizado o procedimento GLM (SAS), e posteriormente obtidas às correlações lineares simples de Pearson utilizando-se o procedimento CORR (SAS). Os valores de intensidade das bandas foram submetidas à hidrólise tripsínica e à espectrometria de massas, utilizando um espectrômetro do tipo eletrospray triplo/quadrupolo. A composição genética não influenciou a maciez da carne, para as diferentes idades para a força de cisalhamento e o índice de fragmentação miofibrilar. O período de maturação só influenciou na maciez da carne até os 7 dias de maturação. A força de cisalhamento e o índice de fragmentação miofibrilar apresentaram correlações significativas. Não foi observada diferença entre idade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study has the objective to: 1) Establish possible correlations between the shear force techniques and the index of myofibril fragmentation to analyze the meet tenderness 2) Identify the myofibrillar proteins of Longissimus dorsi muscle in bovines of cut related to meat tenderness; 3) Study the effect of race, slaughter age and time of maturation in the shear force, the index of myofibrillar fragmentation and myofibrillar proteins. We used 30 animals Nelore breed and 30 animals ½ Nelore ½ Aberdeen Angus, raised in the biological Superprecoce production system that was slaugher with 12 months and commercial animals slaughered with 24 months of age. The samples was submitted to mechanic Warner-Bratzler mechanical Shear Force and MFI determination. The separation of the proteins was held in eletroforese 1D. To evaluate the effect of genetic groups, period of maturation and slaughtering age in the Shear Force, the index of myofibrillar fragmentation and the intensity of band proteins, it was used the GLM(SAS) procedure, and after that the simple linear correlations of Pearson with CORR (SAS) procedure. The values of band intensity were submitted to trypsinic hydrolysis and mass spectrometry, using eletrospray/quadrupole spectrometer. The genetic composition did not influence the meat tenderness, to the different ages to the shear force and myofibrillar fragmentation index. The maturation period only influenced in the meat tenderness 7 days of maturation. The shear force and myofibril fragmentation index had significant correlations. It was not observed difference between age and racial group in tenderness and in degradation of myofibrillar proteins. Only the 30kDa band presented high correlation (r=0,60) with 14 days of maturation period in both the races. This band was submitted to ESI-3Q-MS analysis... (Complete abstract click electronic access below) / Orientador: Paulo Roberto Rodrigues Ramos / Coorientador: Hellen Julie Laure / Banca: Lewis Joel Greene / Banca: Clarica Izumi / Banca: Danísio Prado Murani / Banca: Pedro de Magalhães Padilha / Doutor

Made available in DSpace on 2014-06-11T19:32:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-17Bitstream added on 2014-06-13T19:03:47Z : No. of bitstreams: 1 abrahao_ar_dr_botfmvz.pdf: 1128318 bytes, checksum: 77928a8775fa32c42543f751f23978d3 (MD5) / O presente estudo teve como objetivos: 1) Estabelecer possíveis correlações entre as técnicas de força de cisalhamento e o índice de fragmentação miofibrilar para analise da maciez da carne 2) Identificar as proteínas miofibrilares do músculo Longíssimus dorsi de bovinos de corte, associado à maciez da carne; 3) Estudar o efeito da raça, idade do abate e tempo de maturação, sobre a força de cisalhamento, o índice de fragmentação miofibrilar e as proteínas Miofibrilares. Foram utilizados 30 animais da raça Nelore e 30 animais ½ Nelore ½ Aberdeen Angus, criados no modelo biológico Superprecoce abatios nas idades de 12 meses, e de rebanhos comerciais abatidos com 24 meses de idade. As amostras foram submetidas à análise da força de cisalhamento em um Warner-Bratzler Shear Force mecânico e a determinação do MFI. A separação das proteínas foi realizada em eletroforese 1D. Para avaliar os efeitos de grupos genéticos, período de maturação e de idade ao abate sobre a Força de cisalhamento, Índice de fragmentação miofibrilar e intensidade das bandas proteícas, foi utilizado o procedimento GLM (SAS), e posteriormente obtidas às correlações lineares simples de Pearson utilizando-se o procedimento CORR (SAS). Os valores de intensidade das bandas foram submetidas à hidrólise tripsínica e à espectrometria de massas, utilizando um espectrômetro do tipo eletrospray triplo/quadrupolo. A composição genética não influenciou a maciez da carne, para as diferentes idades para a força de cisalhamento e o índice de fragmentação miofibrilar. O período de maturação só influenciou na maciez da carne até os 7 dias de maturação. A força de cisalhamento e o índice de fragmentação miofibrilar apresentaram correlações significativas. Não foi observada diferença entre idade... / This study has the objective to: 1) Establish possible correlations between the shear force techniques and the index of myofibril fragmentation to analyze the meet tenderness 2) Identify the myofibrillar proteins of Longissimus dorsi muscle in bovines of cut related to meat tenderness; 3) Study the effect of race, slaughter age and time of maturation in the shear force, the index of myofibrillar fragmentation and myofibrillar proteins. We used 30 animals Nelore breed and 30 animals ½ Nelore ½ Aberdeen Angus, raised in the biological Superprecoce production system that was slaugher with 12 months and commercial animals slaughered with 24 months of age. The samples was submitted to mechanic Warner-Bratzler mechanical Shear Force and MFI determination. The separation of the proteins was held in eletroforese 1D. To evaluate the effect of genetic groups, period of maturation and slaughtering age in the Shear Force, the index of myofibrillar fragmentation and the intensity of band proteins, it was used the GLM(SAS) procedure, and after that the simple linear correlations of Pearson with CORR (SAS) procedure. The values of band intensity were submitted to trypsinic hydrolysis and mass spectrometry, using eletrospray/quadrupole spectrometer. The genetic composition did not influence the meat tenderness, to the different ages to the shear force and myofibrillar fragmentation index. The maturation period only influenced in the meat tenderness 7 days of maturation. The shear force and myofibril fragmentation index had significant correlations. It was not observed difference between age and racial group in tenderness and in degradation of myofibrillar proteins. Only the 30kDa band presented high correlation (r=0,60) with 14 days of maturation period in both the races. This band was submitted to ESI-3Q-MS analysis... (Complete abstract click electronic access below)

One of new techniques in the field of analytical chemistry, which has more and more practical use, is mass spectrometry imaging. With its ability to record representation of substances in samples during the tissue analyze arise problem with a lot of output data which needs to be handled programmatically. The goal of this work is to create an software for processing and visualization data of new standard imzML. As a part of the work, the field of mass spectrometry, primarily MALDI TOF mass spectrometry, is briefly introduced. There are also introduced some methods for mass spectrometry data preprocessing. The work also contains a summary of current state of available software for processing and visualization of mass spectrometry data. With requests from cooperating laboratory a novel software is designed and implemented, which besides the visualization itself, can preprocess the data for example data smoothing with Savitzky-Golay method, internal calibration or peak detection with continuous wavelet transformation. The software was successfully tested on real data sets.

No description available.