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A two-level diagnostic baroclinic model is constructed for the purpose of examining the role of latent heat release in the production of vertical motion and rainfall. Incorporated in the model are terrain and frictional inflow effects and a variable level of non-divergence. The computations are carried out on a 300 point standard rectangular grid covering the North American continent. [...]

We present a mixture of latent trait models with common slope parameters (MCLT) for high dimensional binary data, a data type for which few established methods exist. Recent work on clustering of binary data, based on a d-dimensional Gaussian latent variable, is extended by implementing common factor analyzers. We extend the model further by the incorporation of random block effects. The dependencies in each block are taken into account through block-specific parameters that are considered to be random variables. A variational approximation to the likelihood is exploited to derive a fast algorithm for determining the model parameters. The Bayesian information criterion is used to select the number of components and the covariance structure as well as the dimensions of latent variables. Our approach is demonstrated on U.S. Congressional voting data and on a data set describing the sensory properties of orange juice. Our examples show that our model performs well even when the number of observations is not very large relative to the data dimensionality. In both cases, our approach yields intuitive clustering results. Additionally, our dimensionality-reduction method allows data to be displayed in low-dimensional plots. / Early Researcher Award from the Government of Ontario (McNicholas); NSERC Discovery Grants (Browne and McNicholas).

The allylic bromide functionality within brominated poly(isobutylene-co-isoprene), or BIIR, alkylates primary amines repeatedly to generate thermoset products at reaction rates that are too fast to support commercial rubber processing operations. The objective of this work was to assess the utility of latent N-nucleophiles as curatives and modification reagents for BIIR. Ideally, BIIR formulations containing these latent amines would not cure at standard compound mixing temperatures, but support high crosslinking rates and yields upon heating to conventional vulcanization temperatures. Carbon dioxide-derived salts of ammonia, including (NH4)2CO3, (NH4)HCO3 and (NH4)H2NCO2, can be mixed with BIIR without incurring crosslinking at temperatures below 100oC, but they generate adequate crosslink yields upon heating to 160oC. The corresponding CO2-derived salts of primary amines decompose below 100oC and, therefore, do not provide adequate scorch protection when mixed with BIIR. Latency was conferred on primary amines using imine derivatives, in particular N-alkylbenzaldimine and its substituted analogues. These latent curatives are activated by hydrolysis, thereby providing a means of controlling active nucleophile concentrations, and minimizing crosslinking activity at 100oC without impacting negatively on cure rates at 160oC. The scorch problems generated by primary amines extend to BIIR cure formulations employing conventional sulfur and ZnO curatives. In contrast, imine analogues are shown to provide low temperature scorch stability without impacting negatively on high temperature cure rates and extents. / Thesis (Master, Chemical Engineering) -- Queen's University, 2010-02-01 15:18:16.004

Up to date, it is unclear how Choice-Based Conjoint (CBC) models perform in terms of forecasting (external) real world aggregate shop data. In this contribution, we measure the performance of a Latent Class CBC model - not with an experimental holdout sample - but with aggregate real world scanning data. We find that the CBC model does not accurately predict real world market shares. In order to improve the forecasting performance, we propose a correction scheme based on external scanner data. Our analysis based on 8 brands shows that the use of the proposed correction vector improves the performance measure considerably. (author's abstract) / Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

We present techniques for joint modeling of binomial and rank response data using the Bayesian paradigm for inference. The motivating application consists of results from a series of assessments on several primate species. Among 20 assessments representing 6 paradigms, 6 assessments are considered to produce a rank response and the remaining 14 are considered to have a binomial response. In order to model each of the 20 assessments simultaneously, we use the popular technique of data augmentation so that the observed responses are based on latent variables. The modeling uses Bayesian techniques for modeling the latent variables using random effects models. Competing models are specified in a consistent fashion which easily allows comparisons across assessments and across models. Non-local priors are readily admitted to enable more effective testing of random effects should Bayes factors be used for model comparison. The model is also extended to allow assessment-specific conditional error variances for the latent variables. Due to potential difficulties in calculating Bayes factors, discrepancy measures based on pivotal quantities are adapted to test for the presence of random effects and for the need to allow assessment-specific conditional error variances. In order to facilitate implementation, we describe in detail the joint prior distribution and a Markov chain Monte Carlo (MCMC) algorithm for posterior sampling. Results from the primate intelligence data are presented to illustrate the methodology. The results indicate substantial paradigm-specific differences between species. These differences are supported by the discrepancy measures as well as model posterior summaries. Furthermore, the results suggest that meaningful and parsimonious inferences can be made using the proposed techniques and that the discrepancy measures can effectively differentiate between necessary and unnecessary random effects. The contributions should be particularly useful when binomial and rank data are to be jointly analyzed in a parsimonious fashion.

Elastic fibres, a major component of many connective tissues, are composed of an amorphous elastin core surrounded by fibrillin - containing microfibrils. The function of these microfibrils appears to require the co - ordinated interactions of fibrillins with a range of extracellular matrix ( ECM ) macromolecules including, latent transforming growth factor - β ( TGF - β ) binding proteins ( LTBPs ). LTBPs share a high degree of structural similarity to fibrillins, since they both contain unique 8 - cysteine motifs. Of the four members of the LTBP family, LTBPs - 1, - 3 and - 4 covalently bind to latent forms of TGF - β. LTBP - 1 has been shown to interact with the N - terminal domains of fibrillin - 1 and - 2 and LTBP - 4 interacts with the N - terminal domains of fibrillin - 1, suggesting that fibrillin - containing microfibrils may act as TGF - β stores and localise latent TGF - β complexes to the ECM. LTBP - 2 differs from other members of the LTBP family since it does not covalently bind latent TGF - β. However, LTBP - 2 strongly co - localises with fibrillin - containing microfibrils in a number of tissues suggesting that LTBP - 2 could have a structural role associated with these elements presumably independent of TGF - β storage, or could act to mediate specific microfibril - ECM interactions. To understand more about the function of LTBP - 2, this study involved screening for potentially important molecular interactions of LTBP - 2 with fibrillins and a variety of ECM proteins. Human recombinant LTBP - 2 ( r - LTBP - 2 ) was cloned, expressed and purified using a mammalian cell culture system. Solid phase binding assays were used to screen for interactions between r - LTBP - 2 and continguous fragments of fibrillin - 1 and - 2 as well as MAGPs, tropoelastin, collagens and proteoglycans. A cation dependant interaction was found between the C - terminal domains of LTBP - 2 and the N - terminal domains of fibrillin - 1, but not with the analogous region of fibrillin - 2. Thus, LTBP - 2 seems to have an exclusive role associated with fibrillin - 1 - containing microfibrils. Further studies found that the C - terminal region of LTBP - 2 competes with LTBP - 1 for binding to fibrillin - 1, suggesting that the binding site for LTBP - 2 on fibrillin - 1 is the same or in close proximity to that for LTBP - 1. Immunohistochemical analysis of LTBP - 1 and - 2 within developing human aorta indicated that both LTBPs co - localised with fibrillin - 1. However, the two LTBPs did have distinct distribution patterns in relation to each other, in that LTBP - 2 was found throughout the medial layer whereas LTBP - 1 was mainly located in patches of the outer medial layer. No regions of strong co - localisation of the two LTBPs were found. Thus, these findings suggest that LTBP - 2 could indirectly modulate the presence of TGF - β upon the fibrillin - containing microfibrils by competing for binding with the LTBP- 1 / TGF - β complex to these structures. Other binding studies showed a cation independent interaction between r - LTBP - 2 and an as yet unidentified component of a crude bovine collagen - IV extract. Since collagen - IV is a major component of basement membranes, an interaction between r - LTBP - 2 and a protein within this bovine collagen - IV preparation suggests LTBP - 2 may have a further function involving a basement membrane component. It will be interesting to determine if LTBP - 2 acts as a bridging molecule between basement membrane structures and fibrillin - containing microfibrils or if it has another function independent of these microfibrils. / Thesis (Ph.D.)--School of Medical Sciences, 2006.

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 168-180).

Thesis (Ph. D.)--Carleton University, 2004. / Includes bibliographical references (p. 255-269). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Michigan State University. Dept. of Counseling, Educational Psychology and Special Education, 2008. / Title from PDF t.p. (viewed on July 23, 2009) Includes bibliographical references (p. 142-148). Also issued in print.