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Enhanced Detection Strategies Accomplished Through Metal Binding and Miniature Mass SpectrometryGraichen, Adam 01 February 2013 (has links)
A multiplexed method for performing MS/MS on multiple ions simultaneously in a miniature rectilinear ion trap (RIT) mass spectrometer has been developed. This method uses an ion encoding procedure that relies on the mass bias that exists when ions are externally injected into an RIT operated with only a single phase RF applied to one pair of electrodes. The ion injection profile under such conditions ions is Gaussian-like over a wide range of RF amplitudes, or low mass cutoff (LMCO) values, during ion accumulation. We show that this distribution is related to ion m/z and is likely caused by ions having an optimal range of pseudo-potential well depths for efficient trapping. Based on this observation, precursor ion intensity changes between two different injection LMCO values can be predicted, and these ion intensity changes are found to be carried through to their corresponding product ions, enabling multiplexed MS/MS spectra to be deconvoluted.
The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWA. Results show that the metal complex ions can react with low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below the median lethal doses for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.
Mass spectrometry has become a tool for studying noncovalently bound complexes. Specifically, electrospray ionization mass spectrometry (ESI-MS) has found increasing use for the determination of affinity (Ka) or dissociation (Kd) constants. Direct measurement of the equilibrium components by ESI-MS is the most straightforward approach for determining binding equilibrium constants, but this approach is prone to error and has some inherent limitations. Transferring complexes from solution to the gas phase may perturb the equilibrium concentrations and/or different ionization efficiencies may cause the resulting ion signals not to reflect actual solution concentrations. Furthermore, ESI only works under a limited range of solvent conditions (i.e. low ionic strengths), which limits the broad applicability of this approach. We propose an approach based on covalent labeling in the context of metal-catalyzed oxidation (MCO) reactions that, when combined with MS, overcomes such limitations when determining metal-ligand binding constants. The MCO-MS approach will provide concurrent information regarding metal binding site and metal-protein binding affinity. Optimization of the MCO reaction through isotopic mass tags will permit enhanced identification of modified residues. Application of this method to study the affinity and binding interactions of other divalent metals with β2m are likely to provide insight into the specificity of copper for causing β2m amyloid formation.
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The Labour Party and family income support policy; 1940-1979. An examination of the party's interpretation of the relationship between family income support and the labour market.Pratt, Alan January 1988 (has links)
The first two chapters examine the party's policy towards the wage-stop and the poverty trap. Until 1963 the party ignored the wage-stop but from then until 1975 a section of the party campaigned against the regulation expressing moral revulsion and concern about its administration but only rarely opposition to the principle. A Labour government removed the stop when its operation affected only a tiny minority of families. The party was quickly involved in the development of the poverty trap debate being particularly drawn to its disincentive characteristics, but Labour governments, like their Conservative counterparts, soon came to regard the idea as a mere statistical abstraction. After confirming the party's historical ambivalence about Family Allowances the thesis demonstrated that whenever it advocated allowances it did so because it believed the programme would alleviate family poverty rather than augment work incentives. However Labour governments consistently upheld the principle of substitutability, thus conferring de facto support on that less-eligibility dimension of Family Allowances which Macnicol has established informed the coalition government's decision to legislate for the programme in 1945. Despite the party's opposition to Family Income Supplement it became an important element in the Labour government's anti-poverty strategy after the Child Benefits debate in 1976. F.I.S. was criticised because of its contribution to the poverty trap and its potential for assisting in the pauperisation of the low paid, while Child Benefit was supported because it appeared to be a more equitable technique of delivering support to families with dependent children although some in the party were sensitive to the scheme's potential link with improved work incentives. In general, the Labour Party is seen to have failed to develop any coherent and sustained alternative to the ideas and programmes of its political opponents in this critical area of social policy.
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Product Development Collaborations: Implications for Marketing Strategy and InnovationElhelaly, Nehal E. January 2022 (has links)
PhD thesis / High-tech firms are no longer able to rely exclusively on their internal knowledge and technologies to respond effectively to current market dynamics. Instead, they frequently collaborate with external entities to access new technologies and share the costs and risks of the innovation process. However, the effectiveness of such collaborations is questioned by many executives. Yet, as these Product Development Collaborations (PDCs) become crucial for a firm’s growth and success in current times, executives and academics alike are paying growing attention to them. In marketing, PDC is an active research topic since 1999. However, the body of marketing knowledge on the PDC is scattered across several studies over an extended period of more than two decades. In addition, the extant marketing studies report results that are inconsistent on some PDC issues and have overlooked others. In particular, marketing strategy considerations, in terms of firm’s strategic capabilities and objectives, have received somewhat of a short shrift in the literature.
My dissertation contributes to our marketing literature with (a) a systematic review study that synthesizes the current state of marketing knowledge on the topic, identifies the research lacunas, and sets a future research agenda; and (b) two theory-driven empirical studies that provide new insights and novel implications to enrich our understanding of PDCs, their relation to the firm’s marketing strategy, and provide clear guidance to practitioners on how to benefit most from their supplier collaborations.
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Grounding on several theories, creating and using a unique dataset, and utilizing multiple research and econometric techniques, my dissertation empirically addresses the following two general research questions:
RQ1. Can their functional (marketing, technological, and operations) capabilities lead firms into competency traps and hurt their innovation performance? How? Do international PDCs outperform domestic PDCs in combating the competency trap effect? When?
RQ2. What is the appropriate PDC governance mechanism (joint ventures, agreements, or licenses) that would enhance innovation performance? How do governance and capabilities simultaneously impact innovation performance? How does the firm’s product positioning strategy (differentiation versus cost-leadership) interact with governance and capabilities to affect innovation outcomes? / Dissertation / Doctor of Philosophy (PhD) / Many firms establish Product Development Collaborations (PDCs) with suppliers to innovate new products. Although PDCs have numerous advantages, they are ladened by various contractual hazards and risks. This raises concerns of many executives about their effectiveness. In this dissertation, I systematically review the existing marketing studies on the PDC topic. Then, building on my review, I empirically investigate several marketing strategy factors that impact a PDC's effectiveness in terms of enhancing the innovation performance of focal firms.
Drawing on several theories, building and using a unique dataset, and utilizing multiple research and econometric techniques, I conduct two empirical studies to examine the impact of four strategic considerations (i.e., functional capabilities, international PDCs, PDC governance mechanisms, and positioning strategy) and their interactions on innovation performance of high-tech firms in PDCs.
My results reveal various interesting and important relationships and interactions that advance our understating of PDCs, their relation to marketing strategy, and provide important managerial implications to practitioners.
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Analytical Preconcentration Systems Based on Nanostructured MaterialsKijak, Anna M. 09 April 2003 (has links)
No description available.
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INVESTIGATION OF ATOMIC MOTION IN OPTICAL LATTICES VIA INTENSITY CORRELATION MEASUREMENTAgyare, Benjamin A. 06 August 2007 (has links)
No description available.
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Light Shift Measurements of Cold Rubidium Atoms using Raman Pump-Probe SpectroscopySouther, Nathan Jon 19 August 2009 (has links)
No description available.
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Model Based Investigation of Lean Gasoline PM and NOx ControlShivaprasad, Shreyas January 2014 (has links)
No description available.
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Fats, Oils and Greases to Biodiesel: Technology Development and Sustainability AssessmentTu, Qingshi January 2015 (has links)
No description available.
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Neutrophils, Nutritional Immunity and NETs: Host-Pathogen Interactions in <i>Aspergillus fumigatus</i> InfectionClark, Heather Lynn 08 February 2017 (has links)
No description available.
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Low Frequency Noise Characteristics of ZnO Nanowire Field Effect TransistorsXue, Hao January 2016 (has links)
No description available.
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