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Fluorigenic aromatic molecules have found wide application in Fluorescence Spectroscopy. Commercially available fluorigenic reagents have been used to detect amines, amino acids, peptides and proteins. Orthophthalaldehyde (OPA) is an aromatic dialdehyde which is specific for a primary amino group. Three polyaromatic dialdehyde molecules similar to this compound have been synthesised and investigated for their analytical applications. They are: (1) naphthalene-2,3- dicarboxaldehyde (NDA), (2) 1-phenylnaphthalene-2, 3- dicarboxaldehyde (0NDA) and (3) anthracene-2,3- dicarboxaldehyde (ADA).

Probability theory provides a uniquely valid set of rules for plausible reasoning. This enables us to apply this mathematical formalism of probability, also known as Bayesian, with greater flexibility to problems of scientific inference. In this thesis, we are concerned with applying this method to the analysis of visibility data from radio interferometers. Any radio interferometry observation can be described using the Radio Interferometry Measurement Equation (RIME). Throughout the thesis, we use the RIME to model the visibilities in performing the probabilistic analysis. We first develop the theory for employing the RIME in performing Bayesian analysis of interferometric data. We then apply this to the problem of super-resolution with radio interferometers by performing model selection successfully between different source structures, all smaller in scale than the size of the point spread function (PSF) of the interferometer, on Westerbork Synthesis Radio Telescope (WSRT) simulations at a frequency of 1.4 GHz. We also quantify the change in the scale of the sources that can be resolved by WSRT at this frequency, with changing signal-to-noise (SNR) of the data, using simulations. Following this, we apply this method to a 5 GHz European VLBI Network (EVN) observation of the flaring blazar CGRaBS J0809+5341, to ascertain the presence of a jet emanating from its core, taking into account the imperfections in the station gain calibration performed on the data, especially on the longest baselines, prior to our analysis. We find that the extended source model is preferred over the point source model with an odds ratio of 109 : 1. Using the flux-density and shape parameter estimates of this model, we also derive the brightness temperature of the blazar (10¹¹-10¹² K), which confirms the presence of a relativistically boosted jet with an intrinsic brightness temperature lower than the apparent brightness temperature, consistent with the literature. We also develop a Bayesian criterion for super-resolution in the presence of baseline-dependent noise and calibration errors and find that these errors play an important role in determining how close one can get to the theoretical super-resolution limit. We then proceed to include fringe-fitting, the process of solving for the time and frequency dependent phase variations introduced by the interstellar medium and the Earth's atmosphere, in our probabilistic approach. Fringe-fitting is one of the first corrections made to Very Long Baseline Interferometry (VLBI) observations, and, by extending our method to include simultaneous fringefitting and source structure estimation, we will be able to perform end-to-end VLBI analysis using our method. To this end, we estimate source amplitude and fringe-fitting phase terms (phase offsets and delays) on 43 GHz Very Long Baseline Array and 230 GHz Event Horizon Telescope (EHT) simulations of point sources. We then perform model selection on a 5 μas extended Gaussian source (one-fourth the size of the PSF) on a synthetic 230 GHz EHT observation. Finally we incorporate turbulent time-varying phase offsets and delays in our model selection and show that the delays can be estimated to within 10-16 per cent error (often better than contemporary software packages) while simultaneously estimating the extended source structure.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 8 uppsatser.

X-ray crystallography is extensively deployed to determine the structure of proteins, both unbound and bound to different molecules. Crystallography has the power to visually reveal the binding of small molecules, assisting in their development in structure-based lead design. Currently, however, the methods used to detect binding, and the subjectivity of inexperienced modellers, are a weak-point in the field. Existing methods for ligand identification are fundamentally flawed when identifying partially-occupied states in crystallographic datasets; the ambiguity of conventional electron density maps, which present a superposition of multiple states, prevents robust ligand identification. In this thesis, I present novel methods to clearly identify bound ligands and other changed states in the case where multiple crystallographic datasets are available, such as in crystallographic fragment screening experiments. By applying statistical methods to signal identification, more crystallographic binders are detected than by state-of-the-art conventional approaches. Standard modelling practice is further challenged regarding the modelling of multiple chemical states in crystallography. The pervading modelling approach is to model only the bound state of the protein; I show that modelling an ensemble of bound and unbound states leads to better models. I conclude with a discussion of possible future applications of multi-datasets methods in X-ray crystallography, including the robust identification of conformational heterogeneity in protein structures.

The objective of this study is to examine the current practices related to performance measurement in service operational settings. Several statistical procedures are utilized to analyse the data collected from Portuguese service organizations. These procedures include multiple regression analysis, cluster analysis, and gap analysis. Overall, the results of this study indicate that service organizations are beginning to view performance from a broad, organizational perspective. However, they are still, to a certain extent, emphasizing financial measures of performance. This study provides managers of service organizations with valuable insights into the organizational role of performance measures and measurement. This line of research is consistent with the significant growth of the service sector in recent years.

The objective of this study is to examine the current practices related to performance measurement in service operational settings. Several statistical procedures are utilized to analyse the data collected from Portuguese service organizations. These procedures include multiple regression analysis, cluster analysis, and gap analysis. Overall, the results of this study indicate that service organizations are beginning to view performance from a broad, organizational perspective. However, they are still, to a certain extent, emphasizing financial measures of performance. This study provides managers of service organizations with valuable insights into the organizational role of performance measures and measurement. This line of research is consistent with the significant growth of the service sector in recent years.

Asymmetric beams can create significant bias in estimates of the power spectra from cosmic microwave background (CMB) experiments. With the temperature power spectrum many orders of magnitude stronger than the B-mode power spectrum any systematic error that couples the two must be carefully controlled and/or removed. In this thesis, I derive unbiased estimators for the CMB temperature and polarisation power spectra taking into account general beams and scan strategies. I test my correction algorithm on simulations of two temperature-only experiments and demonstrate that it is unbiased. I also develop a map-making algorithm that removes beam asymmetry bias at the map level. I demonstrate its implementation using simulations. I present two new map-making algorithms that create polarisation maps clean of temperature-to-polarisation leakage systematics due to differential gain and pointing between a detector pair. Where a half wave plate is used, I show that the spin-2 systematic due to differential ellipticity can also be removed using my algorithms. The first algorithm is designed to work with scan strategies that have a good range of crossing angles for each map pixel and the second for scan strategies that have a limited range of crossing angles. I demonstrate both algorithms by using simulations of time ordered data with realistic scan strategies and instrumental noise. I investigate the role that a scan strategy can have in mitigating certain common systematics by averaging systematic errors down with many crossing angles. I present approximate analytic forms for the error on the recovered B-mode power spectrum that would result from these systematic errors. I use these analytic predictions to search the parameter space of common satellite scan strategies to identify the features of a scan strategy that have most impact in mitigating systematic effects.

by Bai Tao. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 1-21). / PART I : A new approach to identification by infrared spectrometry / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2 : --- Coding system of IR spectra --- p.13 / Chapter Chapter 3 : --- Library search system of IR spectra --- p.46 / Chapter Chapter 4 : --- Identification of pharmaceuticals by the IR database of pharmaceuticals --- p.64 / Chapter Chapter 5 : --- Identification of Chinese mineral drugs by the IR database of Chinese mineral drugs --- p.85 / Chapter Chapter 6 : --- Identification of Chinese herbal drugs by the IR database of Chinese herbal drugs --- p.114 / Chapter Chapter 7 : --- Coding and library search system for IR spectra of some Chinese mineral drugs with no apparent absorption peaks --- p.133 / Chapter Chapter 8: --- Conclusion to Part I --- p.150 / PART II : A new approach to quantification of solid samples by infrared spectrometry / Chapter Chapter 1: --- Introduction --- p.152 / Chapter Chapter 2: --- Derivative method for the IR spectrometric determination of solid samples using polyethylene film as internal standard(DISPE method) --- p.163 / Chapter Chapter 3: --- The IRQA software for quantitative analysis using IR spectrometry --- p.178 / Chapter Chapter 4: --- IR for the quantitative analysis of some Chinese mineral drugs based on the proposed DISPE method --- p.190 / Chapter Chapter 5: --- Determination of iron-containing species in inorganic mixtures using the proposed DISPE method --- p.204 / Chapter Chapter 6: --- Conclusion to Part II --- p.217 / References for Part I / References for Part II / Appendix I for Part I / Appendix II for Part II