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1
Chan, Chun-yu. "Mass spectrometric analysis of selected glycoproteins." Thesis, Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B3147942X.
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Lorenz, Martin. "Matrix-isolation spectroscopy of mass-selected ions." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962027340.
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Bosnick, Kenneth Andrew. "Raman studies of mass-selected metal clusters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0017/NQ53675.pdf.
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Millar, Alan L. "The mass spectrometry of selected proteins and peptides." Thesis, University of Warwick, 1998. http://wrap.warwick.ac.uk/65228/.
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The multi-subunit alkene monooxygenase was studied by means of electrospray ionisation mass spectrometry (ESI-MS). The measured relative molecular mass (RMM) values for the epoxygenase and reductase were in good agreement the predicted RMM values calculated by means of gene sequencing. Cleavage sites were identified by means ofESI-MS at the N- and C- terminus of the coupling protein. Cleavage at the Cterminus inactivated the protein but was shown to be prevented by the addition of a protease inhibitor, benzamidine. The ceroid lipofuscinosis protein (CLP) was found to contain a +42.2 Da modification. Low energy tandem mass spectrometry confirmed 80% of the primary sequence of the CLP, indicating that the discrepancy in RMM is located on amino acid residues 30-46. Bovine heart mitochondrial subunit c was extracted as a control and was also found to contain the +42.2 Da modification. A study of the interaction ofCLP with its diagnostic inhibitor DCCD was performed. This indicated that the primary product of the reaction was an acetyl-CLP complex and not the expected CLP-DCCD complex. The p-subunit of the soluble methane monooxygenase (sMMO) was investigated by means of ESI-MS to locate and identify a +126.3 Da discrepancy in RMM. A tryptic digestion of the protein indicated the discrepancy to be located in a small digest peptide consisting of amino acid residues 141-146. Low energy MSIMS was used to correct the primary sequence of this peptide. The revised sequence was supported by the close similarity between the DNA nucleotide sequence for the originally suggested amino acid residue sequence and the revised sequence. The binding between a 17 amino acid micro-antibody (Micro-Ab) and two peptides which represent the V3 region of the gp 120 external glycoprotein of the HIV-l envelope protein were studied by means ofESI-MS. It was found that the interaction between the Micro-Ab and the two V3 peptides could be maintained and thus observed directly by ESI-MS. A rapid method of epitope identification was devised whereby the antigen was pre-digested before incubation with the Micro-Ab. The data identified a similar series of amino acid residues in both V3 peptides as the epitope with which the Micro-Ab interacts.
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Coffey, Jonathan A. "Mass spectrometric analysis of selected proteins and peptides." Thesis, University of Warwick, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246785.
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Cuciti, Virginia. "Radio halos in a mass-selected sample of galaxy clusters." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6574/.
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A fraction of galaxy clusters host Mpc-scale Radio
Halos (RH), generated by ultrarelativistic electrons in the
magnetized intra cluster medium (ICM). In the current
view they trace turbulent regions in merging clusters, where relativistic particles are trapped and accelerated. This model has clear expectations about the statistical properties of RHs. To test these expectations large mass-selected samples of galaxy clusters with adequate radio and X-ray data are necessary. We used the Planck SZ cluster catalogue as suitable starting point of our investigation, selecting clusters with M500>6x10^14 Msun at 0.08
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Oduwole, Elizabeth O. "Generation of a database of mass spectra patterns of selected Mycobacterium species using MALDI-ToF mass spectrometry." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2838.
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Thesis (MScMedSc (Pathology. Medical Microbiology))--Stellenbosch University, 2008.The genus Mycobacterium is a group of acid–fast, aerobic, slow- growing organisms which include more than 90 different species. A member of this genus, Mycobacterium tuberculosis, belonging to the Mycobacterium tuberculosis complex (MTB), is the causative agent of tuberculosis (TB). This disease is currently considered a global emergency, with more than 2 million deaths and over 8 million new cases annually. TB is the world’s second most common cause of death after HIV/AIDS. About one-third of the world’s population is estimated to be infected with TB. This catastrophic situation is further compounded by the emergence of Multi Drug Resistant tuberculosis (MDR-TB) and in more recent times, Extensive Drug Resistant tuberculosis (XDR-TB). Early diagnosis is critical to the successful management of patients as it allows informed use of chemotherapy. Also, early diagnosis is also of great importance if the menace of MDR-TB and XDR-TB is to be curbed and controlled. As MTB is highly infectious for humans, it is of paramount importance that TB be diagnosed as early as possible to stop the spread of the disease. Traditional conventional laboratory procedures involving microscopy, culture and sensitivity tests may require turnaround times of 3-4 weeks or longer. Tremendous technological advancement over the years such as the advent of automated liquid culture systems like the BACTEC® 960 and the MGITTM Tube system, and the development of a myriad of molecular techniques most of which involves nucleic acid amplification (NAA) for the rapid identification of mycobacterial isolates from cultures or even directly from clinical specimens have contributed immensely to the early diagnosis of tuberculosis. Most of these NAA tests are nevertheless fraught with various limitations, thus the search for a rapid, sensitive and specific way of diagnosing tuberculosis is still an active area of research. The search has expanded to areas that would otherwise not have been considered ‘conventional’ in diagnostic mycobacteriology. One of such areas is mass spectrometry. This study joins the relatively few studies of its kind encountered in available literature to establish the ground work for the application of mass spectrometry, specifically Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-ToF MS) in the field of diagnostic mycobacteriology. This is an area which is in need of the speed, sensitivity and specificity that MALDI-ToF technique promises to offer. Since this technology is still in its infancy, the use of utmost care in the preparation of reagents, and the handling and storage of the organisms used to generate reference mass spectra for the database cannot be overemphasized. Similarly, the optimization of certain crucial experimental factors such as inactivating method and choice of matrix is of paramount importance. The main aim of this thesis was to generate a database of reference mass spectra fingerprints of selected (repository) Mycobacterium species. This necessitated the standardization of an experimental protocol which ensured that experimental factors and the various instrument parameters were optimized for maximum spectra generation and reproducibility. A standard operating procedure (SOP) for generating the database of reference mass spectra finger print of selected Mycobacterium species was developed and used to investigate the ability of the database to differentiate between species belonging to the same clinical disease complex as well as the nontuberculosis complex. The findings of this study imply that if the defined protocol is followed, the database generated has the potential to routinely identify and differentiate (under experimental conditions) more species of Mycobacterium than is currently practical using PCR and its related techniques. It is therefore a realistic expectation that when the database is clinically validated and tested in the next phase of the study, it will contribute immensely to the diagnosis of tuberculosis and other mycobacterioses. It will also aid in the identification of emerging pathogens particularly amongst the non-tuberculous mycobacteria.
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Holcombe, Andrea Lee. "Selected health implications of low body mass: determinants and health outcomes." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6592.
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While the role of obesity in health outcomes has been well described, the role of low body mass index (BMI), body weight relative to height, has largely been ignored. Those with low BMI are commonly excluded completely or combined with the normal BMI category in BMI studies. However, there have been some studies indicating poorer health outcomes among those with lower BMI, particularly that of increased risk of mortality. The purpose of this study is to explore the role of low BMI throughout the lifespan.
Data from the Health and Retirement Study was used to evaluate 1) the association between childhood health and socioeconomic status (SES) exposures and low BMI in midlife adulthood, 2) the association between low BMI and health related outcomes in midlife adulthood (ages 50 to 65), and 3) the association between low BMI in midlife and health related outcomes, including mortality, over a longer follow-up (maximum of 20 years). To increase sample size, two low BMI definitions were used: the traditional
Few significant results were found. Low BMI status was consistently associated with older age and female gender as well as current smoking status. Childhood exposure of respiratory disease and greater SES disadvantages was more common among those with low BMI in adulthood. In midlife adulthood, low BMI status was associated with increased difficulties with activities of daily living with either definition of low BMI. Increased risk of fracture was associated with a low BMI definition of <18.5. Increased risk of lung disease and decreased risk of high blood pressure was associated with a low BMI definition of ≤20. An analysis of those 30 years old or older found low BMI to be associated with increased risk of mortality and decreased risk of diabetes regardless of low BMI definition. When low BMI was defined as <18.5, those with low BMI were also more likely to experience difficulty with one or more activities of daily living. When low BMI was defined as ≤20, low BMI status was associated with greater risk of lung disease and decreased risk of high blood pressure.
Further research is needed to fully characterize the role of low BMI on health outcomes as well as the role of SES on low BMI. Additionally, there is a need for greater understanding of the potential biological mechanisms of low BMI for health outcomes. Currently, there are few studies evaluating health outcomes and SES of low BMI. Limiting studies to the extreme upper end of the BMI spectrum limits the overall understanding of the role of BMI in health and may overlook unique characteristics and challenges those with low BMI may face.
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Braun, Christian [Verfasser]. "Time-resolved photoelectron spectroscopy of mass-selected metal-water clusters / Christian Braun." Konstanz : Bibliothek der Universität Konstanz, 2012. http://d-nb.info/1026847141/34.
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Moberg, My. "Liquid Chromatography Coupled to Mass Spectrometry : Implementation of Chemometric Optimization and Selected Applications." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7071.
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Wendling, Karen Saretta Glish Gary L. "Methods to detect volatile organic compounds using selected-ion chemical ionization mass spectrometry." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1903.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Dec. 11, 2008). " ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry.
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Cuciti, Virginia <1989>. "Cluster-scale radio emission: analysis of a mass-selected sample of galaxy clusters." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8540/1/Tesi_PhD.pdf.
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Radio halos are Mpc scale diffuse sources located at the center of a fraction of galaxy clusters. In the current theoretical picture, they form via the re-acceleration of electrons in the ICM by means of turbulence, injected during cluster mergers. This scenario allows basic predictions on the formation history of radio halos that can only be tested by analysing large samples of galaxy clusters with adequate radio and X-ray data.
The main goal of this Thesis is to study the first complete large sample of mass-selected galaxy clusters to obtain solid statistical constraints on the connection between radio halos and the dynamics and mass of the host clusters.
We used the Planck SZ catalogue to select a sample of 75 massive galaxy clusters (M500>6x10^{14}Msun) at redshift z=0.08-0.33 and we collected information on the presence or absence of diffuse emission from the literature and from the large observational (GMRT and JVLA) campaign carried out during this PhD project.
We analysed X-ray Chandra and XMM-Newton data to investigate the dynamical properties of clusters.
We updated the radio power-mass scaling relation for radio halos and we found clear evidence for a bimodal behaviour of clusters in both the radio power-mass plane and, for the first time, in the radio emissivity-mass diagram, with radio halos and non-radio halo clusters following two distinct distributions. Similarly to previous studies, we found that this bimodality is clearly connected to the cluster dynamics. For the very first time, we found an increase of the radio halo fraction with the cluster mass, which is remarkably in agreement with theoretical models.
In addition to the statistics of radio halos, the amount of data available in this Thesis led to the discovery of new radio relics, mini halos and head tail radio galaxies in our clusters.
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Malpas, David George. "The mass transport properties of selected membranes in potassium hydroxide solutions of various concentrations." Thesis, Middlesex University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.568381.
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Aspects of the mass transport processes occurring in the ion-exchange membranes, PUDO 193, a Cellophane membrane derived from regenerated cellulose and Permion 2291 40/30, a grafted co-polymer of polyethylene and methacrylic acid, were studied while the membranes were swollen in solutions of KOH of a wide range of concentrations. Measurement of the dimensional changes (length, width and thickness) of as received Cellophane films, after immersion in solutions of KOH, revealed a complex swelling behaviour with the majority of swelling resulting in changes in thickness. Unlike Cellophane, and as a consequence of their different structure, the swelling behaviour of Permion films were found to be less complex. The swelling behaviour was used to determine the porosity of the swollen membranes. The ion-exchange capacity of the mono-functional Permion was obtained by pH titration, a method unsuitable for use with Cellophane since it is not fully exchanged at low external electrolyte concentrations. The ion-exchange properties of Cellophane were determined using atomic absorption techniques and a crion tracer method which was deemed suitable since similar results were obtained for Permion by this method and by pH titration. Transport numbers of potassium ions and transference numbers of water through Cellophane and Permion as single membrane types were obtained using a meticulous technique, which minimised the unwanted effects of diffusion and osmosis. The method obtained transport numbers relevant to a specific concentration by holding solution composition constant and equal on either side of the membrane. The confidence gained in the technique, enhanced by careful cell testing and the application of correction factors, provided a sound basis for the measurement and subsequent understanding of transport behaviour in the less obvious situation, namely in assemblies of membranes. Measurements of the resistance of Cellophane and Permion ftlms equilibrated in solutions of KOH were made. Membrane resistance vs. membrane thickness plots were curved due to current refraction into the region where the membrane was clamped between the two halves of the conductivity cell. The data was linearised using a nonempirical correction factor and hence the accuracy of the measured membrane conductivity was improved. From the primary resistance data, electrolyte conductivity and the mobilities of the potassium and hydroxyl ions in free solution were calculated. The ratio of potassium to hydroxyl ion mobility in free solution formed a basis for a comparison with a similar mobility ratio in the membrane phase. This method allowed a comparison of mobilities in free solution and the membrane phase without the necessity of estimating a suitable tortuosity factor. Models of tortuosity were then introduced to assess the blocking characteristics of the two membranes. The transport properties of assemblies of Cellophane and Perm ion were investigated. Transport numbers entering and leaving the assembly were found to be different and depended on the orientation of the assembly. For the situation where transport numbers were greater leaving the assembly and at low current densities a steady state was reached and the depletion of electrolyte at the interface was replaced by diffusion, osmosis and hydraulic flow. At high current densities depletion of electrolyte at the interface was rapid causing the decomposition of the Cellophane. For the situation where transport numbers were greater entering the assembly, the assembly separated at the Permion/Cellophane interface due to the accumulation of electrolyte, the difference between measured and predicted transport numbers was accounted for by the effects of diffusion and osmosis which occurred mainly in the Cellophane.
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Anum, Samuel Adotey. "The new insurgencies and mass uprisings in Africa and international involvement : selected case studies." Thesis, University of Pretoria, 2017. http://hdl.handle.net/2263/63005.
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The study examined the relationship between mass uprisings and insurgencies and the impact of international involvement on escalation of mass uprisings into an insurgency. The research used the insurgencies of the LRA (Uganda); RUF (Sierra Leone), Boko Haram (Nigeria) and Al-Shabaab (Somalia) as well as the mass uprisings in Tunisia, Egypt and Libya as case studies.
The study established that insurgencies in Africa that relied primarily on terrorism and violence explain criminal rather than political violence. While the mass uprisings in Tunisia, Egypt and Libya revealed normal patterns of conflict, it was established that the case of Libya was a hybrid of mass uprising and insurgent methods that leaned towards a description of a new category of insurgency.
The study further confirmed that internal conditions in a state and the nature of international involvement define the outcomes of a mass uprising or an insurgency in terms of escalation, duration and termination. The comprehensive humanitarian interventions in the insurgencies of the LRA, Boko Haram, Al-Shabaab and the R2P intervention in Libya escalated violence and conflict continuation. In contrast, the limited involvement in the mass uprisings in Tunisia and Egypt resulted in low levels of violence, while the intervention in Sierra Leone terminated the RUF insurgency in view of the associated DDR and institutional building programmes. The study recommends that since humanitarian and military interventions invariably escalate violence and increased fatalities, interventions to end conflicts (mass uprisings and insurgencies) must be based an incremental use of force as a complement to peaceful negotiations.Thesis (DPhil)--University of Pretoria, 2017.
Political Sciences
DPhil
Unrestricted
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Loiselle, Teresa M. (Teresa Marie) Carleton University Dissertation Chemistry. "Analysis of selected proteins using capillary zone electrophoresis with absorbance and mass spectrometric detection." Ottawa, 1995.
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Seeley, Kent W. "Mass Spectrometry-based Methods for the Detection and Characterization of Protein-Tyrosine Nitration." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4766.
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Protein tyrosine nitration (PTN) is a posttranslational modification resulting from oxidative/nitrosative stress that has been implicated in a wide variety of disease states. Characterization of PTN is challenging due to several factors including its low abundance in a given proteome, preferential site modification, multiple target site proximity within unique peptide sequences, and analytical method and instrument limitations. Current analytical techniques are insufficiently sensitive to identify endogenous nitration sites without incorporation of either nitrotyrosine or target protein enrichment. However, enrichment proficiency can also be inadequate. Chemical derivatization of the nitro- moiety can be incomplete or result in undesirable byproduct formation, while immunoaffinity proficiency is contingent upon antibody specificity. To overcome analytical method and enrichment deficiencies, we aimed to develop a comprehensive nitroproteome-specific workflow using molecular methods combined with mass spectrometry. Our approach was to systematically address all relevant factors contributing to PTN such as primary sequence, protein conformation, solvent accessibility, and nitrating agent concentration. Our ultimate goal was to increase mass spectrometric sensitivity for PTN identification. All putative nitroprotein/nitropeptide identifications were then subjected to rigorous validation by either manual spectrum analyses or peptide synthesis. We further developed MS methods for quantitation of nitropeptides from complex mixtures with minimal sample processing. Successful application of our nitroproteome-specific mass spectrometric workflow is expected to provide powerful tools for comprehensive PTN investigation that will elucidate its role in the onset and progression of a variety of disease states as well as facilitate discovery of therapeutic targets.
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Haqqani, Aiman Aafreen. "DEVELOPMENT OF A QUANTITATIVE UNDERSTANDING OF HIV-1 PROTEASE PROCESSING USING MASS SPECTROMETRY." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1548433551709353.
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Stumpo, Katherine Anne. "Size-selected 2, 5, and 10 nm gold nanoparticles for laser desorption/ionization mass spectrometry." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3127.
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Kaposta, Eva Cristina. "Gas phase infrared photodissociation spectroscopy mass selected cluster ions strong hydrogen bonds and vanadium oxides /." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=978049314.
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Lourenco, Celia Maria Farinha. "Applications of proton transfer reaction and selected ion flow tube mass spectrometry in health monitoring." Thesis, Open University, 2017. http://oro.open.ac.uk/49148/.
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This thesis investigates the use of Volatile Organic Compounds (VOCs) in disease diagnosis and monitoring. VOCs may be found in the human body, in exhaled breath, faecal matter, urine, and skin. Analysis of the volatile profile produced in the human body can provide an indicator of metabolic status, allowing the screening and monitoring of different diseases and conditions, non-invasively and painlessly. In this thesis a range of highly sensitive analytical techniques have been adopted to measure such VOCs and demonstrate that such monitoring may be used as a disease diagnostic. For example breath samples may be analysed and calibrated against gas-phase standards prepared under physiologically representative concentrations as a tool for non-invasive disease monitoring, e.g. type 2 diabetes. Detailed faecal headspace analyses of two different mouse models of type 2 diabetes (Cushing´s mice and Afmid) were made. The mouse model of Cushing’s syndrome develop excessive circulating glucocorticoid concentrations, which are associated with obesity, hyperglycaemia and insulin resistance. The Afmid knockout mice suffer inactivation of Afmid genes, which in part regulates many functions including pancreatic secretion. These mice show impaired glucose tolerance. The gut microbiota of diabetic mice appear to have a different composition when compared to wild-type littermates, i.e. significantly increased levels of short-chain fatty acids (SCFAs), ketones, alcohols and aldehydes were found in the faecal headspace of diabetic mice, and a possible link between gut microbiota and type 2 diabetes is demonstrated. The use of VOCs as a screening tool of colorectal cancer was also explored. The current screening tools show lack of sensitivity and specificity for the screening of the disease. The volatile faecal profile of patients with colorectal cancer was investigated, and sulphide compounds, including hydrogen sulphide (H2S) are shown to have potential as biomarkers for screening of colorectal cancer.
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Mekonnen, Tessema Fenta. "Investigating Biotic and Abiotic Transformation Processes of Selected Pesticides Using Electrochemistry Coupled to Mass Spectrometry." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19968.
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In der Entwicklung neuer Agrochemikalien ist es essentiell das weitere Schicksal im Bezug zum Abbau durch abiotische und biotische Einflüsse vorherzusagen. Pestizide gehören zu den Agrochemikalien und durch abiotischen und biotischen Stress werden Transformationsprodukte (TPs) gebildet. Daher ist es von Bedeutung, die TPs von Pestiziden und deren Entstehungsprozess zu untersuchen. Diese Dissertation beschäftigt sich mit biotischen und abiotischen Umwandlungsprozessen von zwei Modell-Pestiziden, nämlich Chlorpyrifos (ein Insektizid) und Fluopyram (ein Fungizid) unter Verwendung von Modellsystemen. Lebermikrosomeninkubation und elektrochemische Durchflusszellen, die an Online-Massenspektrometrie gekoppelt waren, wurden als experimenteller Modellansatz zu untersuchen um die Biotransformationsprozesse (phase I und phase II) der Ziel-Pestizide. Im zweiten Teil dieser Arbeit, wurden Photodegradationsprodukte der beiden Modellverbindungen durch Bestrahlung mit keimtötendem ultraviolettem Licht (200 - 280 nm) untersucht. Im letzten Teil dieser Arbeit wurde die Elektrochemie-Massenspektrometrie auf die Herstellung von Referenzstandards für Transformationsprodukte für das gezielte Screening in Lebensmittelproben ausgedehnt. Die strukturelle Aufklärung der Transformationsprodukte erfolgte mittels HPLC, gekoppelt an verschiedene Massenspektrometrietechniken (Single Quad, Triple Quad, FT-ICR HRMS, Triple TOF-MS, Orbitrap HRMS). Zusammenfassend konnte die Kopplung von EC/(LC)/MS als schnelle, zuverlässige, kostengünstige und matrix-unabhängige Methode genutzt werden, um den oxidativen Phase-I und II Metabolismus von Fluopyram und Chlorpyrifos zu simulieren. EC/MS könnte weiterhin zur Synthese von TP Referenzstandards und zur Messung von Realproben genutzt werden. Neue TPs und deren Bildungsmechanismen konnten im Rahmen dieser Dissertation für beide untersuchten Substanzen identifiziert werden.One of the crucial steps of developing a new agrochemical product is predicting its fate following biotic or abiotic stress. In this regard, pesticides undergo transformation processes in response to biotic and abiotic stress. Therefore, it is important to investigate pesticides’ transformation products (TPs) and the formation processes they undergo. This dissertation deals on biotic and abiotic transformation processes of two model pesticides namely chlorpyrifos (an insecticide) and fluopyram (a fungicide) using model systems. Liver microsome incubation and electrochemical-flow-through cell coupled to online mass spectrometry were used as a model experimental approach to investigate phase I and phase II biotransformation processes of the targeted pesticides. In the second part of this thesis, photodegradation products of the two model compounds were investigated by irradiating with germicidal ultraviolet light (200 – 280 nm). In the last part of this work, electrochemistry-mass spectrometry was scaled-up to the production of transformation product reference standards for targeted screening in different food samples. Structural elucidations of transformation products were performed using HPLC coupled to different mass spectrometry techniques (single quad, triple quad, FT-ICR HRMS, TripleTOF-MS, Orbitrap HRMS). In summary, a fast, reliable, cost-effective and matrix-free simulation of oxidative metabolism (phase I and II) of fluopyram and chlorpyrifos was achieved here by EC/(LC)/MS. EC/MS could, therefore, be scaled up to synthesis TP reference standards for real sample investigation. Additionally, new TPs and their mechanisms were identified for both investigated compounds.
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Davis, Brett Murray. "Volatile Organic Compounds and Antioxidants in Olive Oil: Their Analysis by Selected Ion Flow Tube Mass Spectrometry." Thesis, University of Canterbury. Chemistry, 2007. http://hdl.handle.net/10092/3432.
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The application of Selected Ion Flow Tube Mass Spectrometry (SIFT MS) to the analysis of olive oil shows several distinct advantages over more conventional analysis techniques. The two areas described in this thesis examining olive oil quality are the analysis of Volatile Organic Compounds (VOCs) and the assessment of antioxidant activity. VOCs are responsible for the aroma and much of the taste of olive oil, while antioxidants afford some protection from harmful reactions involving radical species inside the body by scavenging radicals when olive oil is ingested. The VOCs of olive oil are used by sensory panel judges to classify oils by their degree of suitability for human consumption. The major parameters used for this evaluation are the strengths of any defects and the degree of fruitiness. A defect is an indication of an undesired process which has occurred in the oil, while fruitiness is a fragile attribute which denotes a good quality oil and is easily masked by defects. SIFT MS was used to measure the strengths of the olive oil defects rancid, winey, musty, fusty and muddy. Great potential was demonstrated for all defects except musty and the concentrations of VOCs in olive oil head space were correlated with the peroxide value, a measure of the degree of oil oxidation. A study aimed at correlating the strength of the fruitiness attribute as determined by a sensory panel with the concentrations of VOCs in olive oil head space was unsuccessful. The SIFT MS Total Oxyradical Scavenging Capacity (TOSC) assay was used to measure olive oil antioxidants. This assay measures all antioxidants in oil, not only those removed by extraction with a solvent, as it is conducted in an emulsion. SIFT MS TOSC assay results were found to correlate well with those of the widely used Folin Ciocalteu assay and the total concentration of phenolic compounds present in olive oil. Discrepancies between the two assays were most likely due to hydrophobic antioxidants which are measured by the SIFT MS TOSC assay but not the other tests.
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Vandoni, Giovanna. "Helium scattering study of thermal atoms and mass selected clusters deposited on a well defined surface /." Lausanne, 1995. http://library.epfl.ch/theses/?nr=1357.
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Rodrigues, Kevin Liu 1990. "Espectroscopia de capacitância de nanoagregados metálicos selecionados em massa = Capacitance spectroscopy of mass selected metal nanoaggregates." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/276934.
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Orientador: Varlei RodriguesDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
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Resumo: O estudo de nanopartículas é desafiador devido à complexidade destes sistemas, que estão na interface entre o pequeno e o grande. A física dos sólidos deixa de valer em muitas das partículas menores devido ao alto grau de confinamento, e a fração de átomos de superfície para átomos no núcleo. Devido à natureza pequena dos \textit{clusters}, as medidas realizadas nestes sistemas são medidas de alto grau de precisão. Com o objetivo de caracterizar feixes de fontes de agregados de maneira rápida e acessível, um circuito capacímetro é utilizado para medir a influência da deposição de nanopartículas na região dielétrica de um capacitor, uma proposta em aberto na área de nanopartículas. Como essa medida captura a contribuição de inúmeros agregados diferentes, todos depositados na região dielétrica do capacitor, um filtro seletor de massas pode ser utilizado para estreitar a largura da distribuição de tamanhos e obter a influência causada por esse tamanho específico apenas. Neste trabalho será apresentado o projeto para a implementação de um filtro com esse propósito, original de Issendorf e Palmer, cujo princípio de operação é o tempo de voo das partículas, e tem resolução esperada de uma parte em quarenta. Medidas de capacitância também foram realizadas na tentativa de caracterizar a variação da capacitância em função da quantidade de material depositado, com resultados promissores, mas que requerem um maior refinamento das medidas. Os nanoagregados foram produzidos depositados e analisados no Grupo de Física de Nanossistemas e Materiais Nanoestruturados (GFNMN) da física da Unicamp
Abstract: The study of nanoparticles is a challenging one because of the complexity of these systems, which lie on the interface between the small and the big. By that it is meant that many crystals and solids approximations cease to work, and confinement effects begin to appear, as well as surface phenomena which gain strength as surface to volume atoms increase. Due to the small particle sizes, measurements become increasingly difficult, requiring higher and higher precision techniques. With the objective of quickly characterizing beams produced by nanoaggregates sources, a capacitance measuring circuit was created with the intent of measuring the influence of the aggregates on the dielectric constant of the medium between the electrodes, a technique which has not been applied to cluster beams yet. In combination with the capacitance measurements, a mass selecting device was built in order to make the capacitance measurements reflect only a narrow mass distribution, allowing the study of properties of a single cluster size provided they are small enough. In this study will be discussed the project for such a mass filter, original by Issendorf and Palmer, and its implementation on a cluster source. Its principle of operation is the time of flight mass spectrometry, and its projected resolution of about one part in forty. Capacitance measurements were also performed to try and characterize the capacitance change as a function of the density of deposited material. The results were promissing but require further refinement for a strong correlation. All the particle beams were produced at the cluster source operating at the GFNMN group at the department of applied physics at IFGW Unicamp
Mestrado
Física
Mestre em Física
2011/15018-7
FAPESP
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Siddique, Muhammed Rashid. "Improving leukaemia diagnosis and management with Selected Ion Flow Tube Mass Spectrometry and vibrational spectroscopy techniques." Thesis, Keele University, 2017. http://eprints.keele.ac.uk/3138/.
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Leukaemia is 11th most common cancer worldwide, associated with poor prognosis. The 10 years’ survival for leukaemia is between 44%-47%. One of the main reasons for this is the disease being diagnosed in late stages. Most of leukaemia screening techniques are invasive or give radiation. It is therefore obvious to improve prognosis and refine diagnostic techniques for early detection, and better management of its therapeutic response. Spectroscopic and spectrometric techniques are widely used by a huge group of scientists; as biochemical analysis of the disease, may provide biochemical signatures to be used in diagnostics and management of the disease. In this work, the feasibility of measuring both qualitatively and quantitatively VOCs released by PBMC, leukaemia cells and BM cells in vitro has been shown. There are clear differences in the VOCs profile even among different leukaemia cells lines as well as from leukaemia cells exposed to drugs, PBMCs and bone marrow. These differences in the VOCs release could be exploited towards a clinical application of SIFT-MS in the diagnosis and therapeutic response of the disease. Direct sampling is the most convenient method of sampling, which could avoid loss of the many important VOCs by diffusion and/or absorption. Since it is not very easy to obtain direct breath, appropriate storage of exhaled breath and transportation are very important issues to be considered. My study proved that stability over time might vary for different VOCs, especially those present in smaller concentrations. The addition of Imatinib or Nilotinib to K562 cell clones induces changes in cell biology and cellular structure which translates into changes in the S-FTIR spectra and Raman Spectra of the cells. There are remarkable differences in the biochemical composition of cells incubated at different drug concentrations and at different levels of oxygen. Further studies are needed to confirm these changes in the spectra.
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Krishnaswamy, Sangeetha. "Kinetics of volatile generation during coffee roasting and analysis using Selected Ion Flow Tube-Mass Spectrometry." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492506642418004.
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Nesati, Victor Joseph. "Study of selected proteins and noncovalent protein-protein complexes by nano- and electrospray ionization tandem mass spectrometry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/NQ48682.pdf.
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Wende, Torsten [Verfasser]. "Gas phase infrared photodissociation spectroscopy of mass-selected ionic clusters : metal oxides and microhydrated anions / Torsten Wende." Berlin : Freie Universität Berlin, 2012. http://d-nb.info/1030488509/34.
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Smyth, Thomas James Patrick. "The isolation, separation, bioactivity testing and mass spectrometric characterisation of selected nicotines, coumarins and Australian natural products." Thesis, University of Ulster, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494406.
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Reed, Christine Jane. "The Characterisation and Development of a Passivated Inlet to Selected Ion Flow Tube Mass Spectrometry (SIFT-MS)." Thesis, University of Canterbury. Chemistry, 2010. http://hdl.handle.net/10092/4995.
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SIFT-MS is a relatively new trace gas analysis technique that has wide application. One particular attribute of the instrument is the ability to detect and quantify volatile organic compounds to the parts per trillion in real-time without the need for sample preparation. However the issue of maintaining accuracy at these low concentrations required attention as it was evident large or polar analytes were being lost by adsorption to the SIFT instrument’s inlet system.
The purpose of this research was to evaluate the performance of a passivated inlet in lowering any adsorption in the inlet system compared to the current unpassivated inlet of the SIFT instrument. Volatile concentrations of vanillin (C₈H₈O₃ 152.15 g/mol), ammonia (NH₃ 17.03 g/mol), and hydrogen sulfide (H₂S 34.08 g/mol) were measured. The results determined the passivated inlet provided a significantly better inlet response to these compounds. Consequently improved passivated inlets were installed on current models of SIFT-MS VOICE200®, and also the research laboratory VOICE100™ instrument.
Having established a more reliable sampling system for very low concentrations of analyte, attention was paid to SIFT-MS flavour analysis of two foods, cheese and chocolate. The volatile matrix of these foods is highly complex and the compounds of interest are typically difficult to measure. The key aroma compounds for analysis were based on reported literature and earlier SIFT-MS studies which provided a useful framework for the current food flavour research.
A significant finding from the SIFT-MS examination of Parmesan cheese is that differences in the relative concentration of some characteristic aroma compounds were a consequence of the milk type used in manufacture. Endogenous enzymes responsible for a multitude of reactions are mostly if not completely inactivated by the pasteurization temperature. A similar analysis approach was attempted for chocolate analysis. Here flavour differences were not as clearly recognised as for the cheese samples. In chocolate there are a greater number of parameters that are involved in its manufacture. Nevertheless, some recognisable differences in chocolate could be attributed to cocoa bean type and flavour additions by the manufacturer.
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Zhang, Yachen Zhang. "Analysis of strawberry volatiles in different hydrocolloids and different conditions using Selected Ion Flow Tube – Mass Spectrometry." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462280966.
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Wu, Yajun Wu. "Investigation Of Corrosion In Canned Chicken Noodle Soup Using Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS)." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469174410.
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Chippendale, Thomas W. E. "Volatile biomarkers emitted by cell cultures : headspace analysis using selected ion flow tube mass spectrometry, SIFT-MS." Thesis, Keele University, 2012. http://eprints.keele.ac.uk/3724/.
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The work presented in this thesis was initiated in order to develop a non-invasive real-time gas phase analytical technique, based on selected ion flow tube mass spectrometry (SIFT-MS), for monitoring the progression of human cell cultures and the detection of microbial contamination in such cultures by monitoring and quantifying the emitted volatile compounds. Fundamental SIFT experiments were performed to characterise the reactions of the SIFT-MS precursor ions (H3O+, NO+ and O2 +●) with several volatile compounds of potential value to biological research; a necessity for their quantification. The work has resulted in new methods for the quantification acetaldehyde and CO2 in gaseous samples. The compounds present in the headspace of sealed cultures of six human cell types were analysed by SIFT-MS, the key finding being their consumption of the toxic volatile compound acetaldehyde from the media. Further experiments involved the addition of the enzyme aldehyde dehydrogenase inhibitors diethylaminobenzaldehyde and disulfiram to cultures of hepG2 (hepatocellular carcinoma) cells, when it was observed that consumption of acetaldehyde from the cultures/headspace was reduced, and in some cases, acetaldehyde was even produced due to the actions of the cellular alcohol dehydrogenase enzyme. Furthermore, the solvent dimethylsulphoxide was reduced to imethylsulphide by the cells, which is known to occur via the enzyme methionine sulphoxide reductase. This process was retarded by the ALDH inhibitors. The use of SIFT-MS for the detection of microbial infection in mammalian cell cultures was also explored. The volatile compounds emitted by E. coli (strain JM109), into the gas phase above two different culture media, were analysed using SIFT-MS. Further, the progression of a culture of this bacterium was monitored continuously over a 4-hour period. The findings of this research were then applied to the study of human cell cultures intentionally infected by E. coli bacterium, including cultures contained in a 1L bioreactor.
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Deb, Nabanita. "Towards cold state-selected ion-molecule reactions." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:1a3899d3-7476-49ac-8f4b-3c0e7a7e8680.
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In recent years there has been much progress in the field of cold and ultracold molecular physics and a variety of experimental techniques for producing cold matter now exist. In particular, the generation of trapped molecular ions at mK temperatures has been achieved by sympathetic-cooling with laser-cooled atomic ions. By implementing schemes to selectively prepare and control the internal quantum state of molecular ions, and developing detection techniques, it will be increasingly possible to study cold state-selected chemical collisions in an ion-trap. Most molecular species produced in a selected rovibrational state have a lifetime of a few seconds, before the population is redistributed across numerous rovibrational states by interaction with the ambient blackbody radiation (BBR). Consequently, the investigation of state-selected reaction dynamics at low temperatures in experiments where long time scales (minutes to hours) are required, is hindered. This thesis looks into developing strategies that maintain state selection in molecular ions, allowing one to observe state-selected reactions in cold environments, in particular the state-selected reaction between C2H+2 and ND3. Examining reactive ion molecule collisions under cold conditions provides insight into fundamental reaction dynamics, which are thermally averaged out at higher temperatures. A theoretical model is used to investigate laser-driven, blackbody-mediated, rotational cooling schemes for several 1Σ and 2Π diatomic species. The rotational cooling is particularly effective for DCl+ and HCl+, for which 92% and >99% (respectively) of the population can be driven into the rovibrational ground state. For the other systems a broadband optical pumping source is found to enhance the population that can be accumulated in the rovibrational ground state by up to 29% more than that achieved when exciting a single transition. The influence of the rotational constant, dipole moments and electronic state of the diatomics on the achievable rotational cooling is also studied. This approach is extended to consider the BBR interaction and rotational cooling of a linear polyatomic ion, C2H+2, which has a 2Π electronic ground state. The (1-0) band of the ν5 cis-bending mode is infrared active and strongly overlaps the 300 K blackbody spectrum. Hence the lifetimes of state-selected rotational levels are found to be short compared to the typical timescale of ion trapping experiments. Laser cooling schemes are proposed that could be experimentally viable, which involves simultaneous pumping of a set of closely spaced Q-branch transitions on the 2Δ5/2-2Π3/2 band together with two 2Σ+– 2Π1/2 lines. It is shown that this should lead to >70% of total population in the lowest rotational level at 300 K and over 99% at 77 K. In order to identify states of the acetylene ion that could be trapped sufficiently long enough for state-selected reactions in the ion trap with decelerated ND3, the theoretical work has been complemented by experimental investigations into the production of C2H+2 in selected states, and ion trapping of the same using sinusoidal and digital trapping voltages. Appropriate (2+1) REMPI (Resonance Enhanced Multiphoton Ionization) schemes are used to produce C2H+2 in different quantum states, with (1+1) Resonance Enhanced Multiphoton Dissociation (REMPD) employed to detect the ion thus produced. The concept of digital ion trapping for ejection onto MCPs is introduced. A comprehensive comparison between sinusoidal and digital trapping fields has been performed with respect to trap depth and stability regions. Programs have been developed to calculate the stability regions for different ions under varying experimental conditions. The trap depth has been derived for both digital and sinusoidal trapping fields. It is observed that as τ increases, the trap depth of a digital trap increases. For τ = 0.293, the trap depth and stability diagram for both sinusoidal and digital trapping fields would be equivalent. The trap depth at which the sinusoidal trap operates experimentally in our research group is ~1.36 eV. In contrast, the experimental parameters at which the digital trap operates generates a trap depth of 1.21 eV. Ca+ Coulomb crystals have been formed, stably trapped and stored for extended periods of time in both sinusoidally and digitally time-varying trapping fields. The sympathetic cooling of a diverse range of ions into Ca+ Coulomb crystals is demonstrated, again using both sinusoidal and digital trapping fields. Mass spectrometric detection of ionic reaction products using a novel ejection scheme has been developed, where ejection is achieved by switching off the trapping voltage and converting the quadrupole trap into an extractor-repeller pair by providing the ion trap electrodes with appropriate ejection pulses. This technique is developed using a digital trapping voltage rather than the sinusoidal trapping voltage, as ejection with sinusoidal trapping voltages is not clean (resonance circuitry used in the electronics induces ringing after switching off the trapping voltage). Coulomb crystals, both pure Ca+ and multi-component crystals, are ejected from the ion trap and the TOF trace obtained is recorded on an oscilloscope. When the integrated, base-line subtracted TOF peak is plotted against the number of ions in a Ca+ crystal and sympathetically-cooled Ca+ – CaF+ crystal, a linear relationship is obtained. This technique is found to be well mass-resolved, with the signal arising from CaOH+ (57 amu) and CaOD+ (58 amu) resolvable on the TOF trace. This technique would enable one to monitor a reaction in a Coulomb crystal where the reactant and product species are both either lighter or heavier than calcium, such as the reaction between C2H+2 and ND3, something which has not been previously possible. It is, also, potentially a very important technique for reactions with many product channels.
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Lalanne, Matthieu Raphael [Verfasser]. "Gas Phase Formation and Photodissociation Spectroscopy of Mass Selected Nitrogen and Oxygen Substituted Carbon Clusters / Matthieu Raphael Lalanne." Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1119151279/34.
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Schröder, Christoph [Verfasser], Heinz [Akademischer Betreuer] Hövel, and Dmitri [Gutachter] Yakovlev. "Mass selected clusters on weakly interacting surfaces investigated with UPS / Christoph Schröder. Betreuer: Heinz Hövel. Gutachter: Dmitri Yakovlev." Dortmund : Universitätsbibliothek Dortmund, 2015. http://d-nb.info/1110893507/34.
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Wolter, Dominik [Verfasser], Heinz [Akademischer Betreuer] Hövel, and Mirko [Gutachter] Cinchetti. "Mass selected copper clusters on well-ordered aluminum oxide layers / Dominik Wolter ; Gutachter: Mirko Cinchetti ; Betreuer: Heinz Hövel." Dortmund : Universitätsbibliothek Dortmund, 2018. http://d-nb.info/1160763704/34.
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Azcarate, Carolina. "Effect of Enzyme Activity and Frozen Storage on Jalapeño Pepper Volatiles by Selected Ion Flow Tube – Mass Spectrometry." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274810596.
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Nezami, Ranjbar Mohammad Rasoul. "Novel Preprocessing and Normalization Methods for Analysis of GC/LC-MS Data." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73499.
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We introduce new methods for preprocessing and normalization of data acquired by gas/liquid chromatography coupled with mass spectrometry (GC/LC-MS). Normalization is desired prior to subsequent statistical analysis to adjust variabilities in ion intensities that are not caused by biological differences. There are different sources of experimental bias including variabilities in sample collection, sample storage, poor experimental design, noise, etc. Also, instrument variability in experiments involving a large number of runs leads to a significant drift in intensity measurements. We propose new normalization methods based on bootstrapping, Gaussian process regression, non-negative matrix factorization (NMF), and Bayesian hierarchical models. These methods model the bias by borrowing information across runs and features. Another novel aspect is utilizing scan-level data to improve the accuracy of quantification. We evaluated the performance of our method using simulated and experimental data. In comparison with several existing methods, the proposed methods yielded significant improvement. Gas chromatography coupled with mass spectrometry (GC-MS) is one of the technologies widely used for qualitative and quantitative analysis of small molecules. In particular, GC coupled to single quadrupole MS can be utilized for targeted analysis by selected ion monitoring (SIM). However, to our knowledge, there are no software tools specifically designed for analysis of GS-SIM-MS data. We introduce SIMAT, a new R package for quantitative analysis of the levels of targeted analytes. SIMAT provides guidance in choosing fragments for a list of targets. This is accomplished through an optimization algorithm that has the capability to select the most appropriate fragments from overlapping peaks based on a pre-specified library of background analytes. The tool also allows visualization of the total ion chromatogram (TIC) of runs and extracted ion chromatogram (EIC) of analytes of interest. Moreover, retention index (RI) calibration can be performed and raw GC-SIM-MS data can be imported in netCDF or NIST mass spectral library (MSL) formats. We evaluated the performance of SIMAT using several experimental data sets. Our results demonstrate that SIMAT performs better than AMDIS and MetaboliteDetector in terms of finding the correct targets in the acquired GC-SIM-MS data and estimating their relative levels.Ph. D.
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Nkambule, Ntombizodwa Rosemary. "Association between diet dental caries and body mass index amongst grade six learners at selected primary schools in Tshwane." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/65843.
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Introduction: Childhood obesity and dental caries (DC) have increased worldwide and are continuing to pose challenges to public health. The increasing risk of obesity for children is of particular concern because research has suggested that childhood obesity predicts adult obesity. Children experiencing DC early in their lives have a much greater probability of subsequent caries in their permanent dentitions and adulthood. Studies have reported a strong association between the nutritional intake and DC and reported a direct link between DC, sugar consumption and obesity. Objectives: to assess the association between dental caries (DC), the Body Mass Index (BMI) and diet among grade six learners at selected primary schools in Tshwane West District. Methods: A cross-sectional analytical study of grade six learners was carried out in Tshwane. The data collection consisted of a questionnaire, clinical oral examination and anthropometric measurements. All clinical data was collected by a single calibrated examiner. A validated questionnaire was used to collect the demographic data and the type of diet consumed. The SPSS version 23 software was used for analysis. Descriptive statistics, Chi-Square test to test for significance for categorical data and logistic regression analysis were used to determine statistical significance. Results: The response rate was 83% (440) and of these 53% were male. The mean age of the participants was 11.8yrs. The majority of the participant’s fathers (71%) and 50% of mothers were employed. The DC prevalence was 43% with a mean DMFT score of 1.19 (SD= ±1.79). The PUFA score was zero. Less than half (47%) of the participants reported to brush their teeth twice daily. The majority (71%) claimed to drink between one and one and a half glasses of sugar-sweetened beverages (SSBs) with 67% eating between one and three sweets per day. While most of the participants reported having a balanced meal at supper, a third reported eating junk food. The majority (71%) of participants had a BMI score that was within the normal range with 19% being overweight. There were no significant associations between the mean DMFT, BMI scores and the SES of the participants. Conclusion: The DMFT was low, but the decayed component was relatively high. The PUFA score was zero. Most participants were classified as having a “normal” BMI with almost a quarter being classified “overweight”. There were no significant associations between the DMFT and the mean BMI scores and SES of the learners. More than half of the participants were from a medium SES and had a slightly high DMFT score than their counterparts. Less than half reported to brush their teeth daily, most of them had a balanced diet at supper.Dissertation (MChD)--University of Pretoria, 2017.
Community Dentistry
MChD
Unrestricted
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Wampler, Brendan. "Volatile generation in bell peppers during frozen storage and thawing using selected ion flow tube mass spectrometry (SIFT-MS)." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1323958423.
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Antobreh, Andrew Akwasi. "Channelised and open-slope processes of mass sediment transport their morphological and seismic characterisation from selected Atlantic high productivity regions /." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979703700.
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Bataineh, Mahmoud. "Separation and determination of selected organic pharmaceuticals in waters by means of natural flat membranes, GC, HPLC, and mass spectrometry." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974403776.
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Studzinski, Harald [Verfasser]. "Ultrafast radiationless dynamics of selected electronically excited aromatic molecules by femtosecond time-resolved mass spectrometry and photoelectron imaging / Harald Studzinski." Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/1019553545/34.
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Towers, Brittany N. "Rapid Quality Assessment of Corn-Based products by Infrared Spectroscopy and Selected Ion Flow Tube Mass Spectroscopy with Multivariate Analysis." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366368685.
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Bowman, Tessa Leigh. "Analysis of factors affecting volatile compound formation in roasted pumpkin seeds with selected ion flow tube mass spectrometry (SIFT-MS)." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306242976.
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Agila, Amal. "Volatile Profile of Cashews (Anacardium occidentale L.), Almonds, and Honeys from Different Origins by Selected Ion Flow Tube Mass Spectrometry." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1341334757.
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Castada, Hardy Zingalaoa. "A FUNDAMENTAL AND APPLIED APPROACH TO SELECTED ION FLOW TUBE-MASS SPECTROMETRIC STUDY OF VOLATILE ORGANIC COMPOUNDS IN SWISS-TYPE CHEESES." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405986395.
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Kujawinski, Dorothea [Verfasser], Torsten Claus [Akademischer Betreuer] Schmidt, and Oliver J. [Akademischer Betreuer] Schmitz. "Liquid Chromatography coupled to Isotope Ratio Mass Spectrometry of Selected Polar Compounds / Dorothea Kujawinski. Gutachter: Oliver J. Schmitz. Betreuer: Torsten Claus Schmidt." Duisburg, 2014. http://d-nb.info/1064580912/34.
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Grönhagen, Niklas [Verfasser], Heinz [Akademischer Betreuer] Hövel, and Markus [Akademischer Betreuer] Betz. "Cluster-Surface Interaction of Mass Selected Ag Clusters with Graphite, Gold and C60 Functionalized Surfaces / Niklas Grönhagen. Betreuer: Heinz Hövel. Gutachter: Markus Betz." Dortmund : Universitätsbibliothek Dortmund, 2011. http://d-nb.info/1098312120/34.
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