no / The prevalence of micromoulded components has steadily increased over recent years. The production of such components is extremely sensitive to a number of variables that may potentially lead to significant changes in the surface geometry, often regarded as a crucial determinant of the product¿s functionality and quality. So far, traditional large-scale quality assessment techniques have been used in micromoulding. However, these techniques are not entirely suitable for small scales . Techniques such as Atomic Force Mi- croscopy (AFM) or White Light Interferometry (WLI) have been used for obtaining full three-dimensional profiles of micromoulded components, pro- ducing large data sets that are very difficult to manage. This work presents a method of characterizing surface features of micro and nano scale based on the use of the Biharmonic equation as means of describing surface profiles whilst guaranteeing tangential (C1) continuity. Thus, the problem of rep- resenting surface features of micromoulded components from massive point clouds is transformed into a boundary-value problem, reducing the amount of data required to describe any given surface feature.The boundary condi- tions needed for finding a particular solution to the Biharmonic equation are extracted from the data set and the coefficients associated with a suitable analytic solution are used to describe key design parameters or geometric properties of a surface feature. Moreover, the expressions found for describ- ing key design parameters in terms of the analytic solution to the Biharmonic equation may lead to a more suitable quality assessment technique for micromoulding than the criteria currently used. In summary this technique provides a means for compressing point clouds representing surface features whilst providing an analytic description of such features. The work is applicable to many other instances where surface topography is in need of efficient representation. / EPSRC

This is the first comprehensive systematic review of the definitions used for retention measures in HIV care. This review provides a compilation of existing definitions of retention in HIV care in randomized controlled trials. In summary, we report very little consensus regarding definitions of retention in HIV care in the research literature. We report and compare definitions of retention so researchers can weigh their definitions with the body of definitions, with the ultimate aim of motivating the research community to establish a clear and unambiguous definition. This work will provide resources for researchers to recommend a definition of retention. Future research is needed to seek practitioners’ views on the most unambiguous, explicit definition of retention. This is only a first step in research toward a standard definition of retention. / Introduction Retention in HIV care is critical for PLHIV. However, retention in HIV care is not measured uniformly across studies. The aim of this study within a review (SWAR) is to describe the diversity in definitions used for retention in HIV care in randomized controlled trials. Methods We conducted a SWAR, drawing data from an overview of systematic reviews on interventions to improve the HIV care cascade. A comprehensive and exhaustive search was conducted of the following databases: PubMed, Excerpta Medica data BASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycINFO, Web of Science, and the Cochrane Library. We identified randomized controlled trials (RCTs) of interventions to improve retention in care for people living with HIV (PLHIV). First, from the included studies in systematic reviews and second using targeted searches for RCTs. Only English language systematic reviews were included, but RCTs in any language were eligible. Data were screened and extracted in duplicate using pre-set criteria, with arbitration as needed. We identified distinct components from the definitions used to measure retention. The components were further categorized based on the similarities between them. We described the components narratively and presented the definitions in tables. Results We identified 8001 records, after a duplication check, 4147 unique titles and abstracts were examined for relevancy, leaving 744 articles. Full-text screening of the articles resulted in 50 articles that measured retention and provided 59 definitions for retention in care. Of the included studies, 11(22%) were conducted in low-income countries, 12(24%) were conducted in lower-middle-income and upper-middle-income countries, and 13(26%) were conducted in high-income countries. We identified ten different components used to define retention. These components are follow-up times (83%), administrative records (8%), clinical visits (61%), gap scores (8%), group-level measures (17%), lab records (15%), pharmacy-based measures (29%), scheduled visits (27%) and visit counts (17%). The most frequently used components are follow-up times (n=49), and the easiest to measure are retention data derived from administrative records (n=5). We put the components into categories based on the similarities between them. Conclusion We identified existing definitions of retention in HIV care and the commonly used components in the definitions. This compilation of the definitions and identification of the components may provide a framework for developing the standard globally agreed-upon definition of retention in HIV care. / Thesis / Master of Health Sciences (MSc) / Globally, there are more than 37.7 million people living with HIV (PLHIV). Retention in human immunodeficiency virus (HIV) care is a common and modifiable determinant of increased adherence to antiretroviral therapy (ART), better health outcomes, and a better quality of life. There is no consensus in the literature on measures of retention in HIV care. This makes it very difficult to compare different studies and jurisdictions. This thesis review summarizes the definitions of retention used in randomized controlled trials (RCTs) and identifies the various components used to measure retention, which can be used as a reference for researchers to identify the gaps in the current definitions for HIV retention measures and identify preferred measures with the goal of reaching a standard consensus definition of retention in HIV care.

<p> In this thesis a systematic and short method for computing the expected values of mean squares has been developed. One chapter is devoted to the theory of regression analysis by the method of least squares using matrix notation and a proof is given that the method of least squares leads to an absolute minimum, a result which the author has not found in the literature. For two-way classifications the results have been developed for proportional frequencies, a subject which again has been neglected in the literature except for the Type II model. Finally, the methods for computing the expected values of the mean squares are applied to nested classifications and Latin square designs.</p> / Thesis / Master of Arts (MA)

The primary seismic response mode of freestanding slender building contents is rocking. Rocking is one of the most damaging response modes due to large accelerations at impact and the possibility of toppling. This study investigates the rocking response of contents within fixed-base and base-isolated buildings so that better-informed decisions can be made, either at the design stage for new structures or during the performance evaluation for existing structures, to mitigate the effects of the destructive rocking behaviour and consequently minimize injury, economic loss, and downtime. A 3D model of a hospital building was created in OpenSees and analyzed to obtain floor accelerations for a suite of 20 broadband ground motions. These motions were then used as input to compute the rocking responses of many building contents. The rocking responses were compared and contrasted to determine the effect of the block’s size, slenderness, floor level, and placement within a level. The rocking response of contents in buildings isolated with lead plug and triple friction pendulum bearings were compared to the fixed-base building to determine the effectiveness of isolation as a means to control rocking. Fragility curves were also created for the fixed-base and isolated buildings. The vertical component of the floor accelerations had little effect on the rocking response of contents. The significance of this is that the location of an object on a given story does not affect its rocking response. However, higher vertical accelerations did increase the likelihood of the object lifting off the floor. The rocking response of stocky contents increased from one story to the next, but as the slenderness increased this transition became less evident. Base isolation was found to be effective at reducing both the likelihood to uplift and overturn. The longer period systems provided superior protection despite the long period pulse like motion while the damping of the systems had little effect on the rocking response. / Thesis / Master of Applied Science (MASc) / During an earthquake slender building contents respond by rocking about their edges. Rocking causes damage to sensitive and brittle objects as well as safety hazards if it results in the overturning of heavy objects. One goal of this study was to define the rocking response of rigid contents in a conventional braced frame hospital. In general, larger and stockier objects were less likely to overturn. Also, overturning was more prevalent higher up in the building while the location of an object within a given story had little effect. Another objective was to determine the effectiveness of base isolation, a technique that decouples the motion of the building from the ground using flexible bearings, as a strategy to protect contents that are vulnerable to rocking during an earthquake. This was found to be quite effective at reducing both the occurrence of uplift (the initiation of rocking) as well as toppling.

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The ZEBRA battery based on Na/NiCb chemistry shows promise for powering electric vehicles and load leveling systems. The ZEBRA cell consists of a liquid sodium negative electrode separated from the positive electrode by a W'-alumina solid electrolyte. The current state of development of this battery makes use of glass sealing and thermo compression sealing as an integral part of the cell assembly. One objective of the present research was to reduce the thickness of the W'alumina electrolyte thickness as a means to improve perfomance, by lowering the internal cell resistance. The second objective was to develop a ceramic seal with matching thermal expansion coefficient (TEC) to increase battery durability. An added benefit realized with the new ceramic seal was its use for high temperature applications such as emf measurements ordinary systems to determine thermodynamic properties. Dense electrolyte tubes with reduced thickness of less than 100 J..Lm and supported on a porous substrate were successfully produced by slip casting. The slip casting parameters, sintering conditions and materials were optimized and electrolyte resistance was measured by a DC method. A ceramic seal was developed from a eutectic mixture of Na20 and Al203 and tested in galvanic cells. The reproducibility of the emf data shows that the seal is fully impervious and can sustain a high alkali pressure atmosphere up to 1 000°C without cracking or degradation. The seal microstructure revealed liquid phase formation of the seal and diffusion bonding with the lid and tube. The thermodynamic properties and phase relations of the Na-Si binary system were studied by the emf method using Na|β-alumina|Si-Na galvanic cells over the whole composition range below 600°C. There is very limited solubility of Si in molten Na. Properties of the sodium silicon compounds were determined from the emf measurements. / Thesis / Doctor of Philosophy (PhD)

<p> Sap flow measurements scaled to represent canopy transpiration (Ec) and eddy covariance measurements of total forest water vapour flux (E) were compared with soil water, meteorological measurements and modelled interception estimates to quantify the above canopy flux of water to the atmosphere from a temperate White pine ecosystem located on the Norfolk sand plain at Turkey Point, Ontario, for the growing season of 2006. Hydraulic redistribution (HR) was found to have occurred at the site on 26 days during the study (growing season of 2006). During a drought period in June, the nightly increases in stored water (up to 0.50 mm) provided by HR reduced drought intensity in the root zone by maintaining soil water contents ( 0) at levels above the water content associated with the approximate wilting point(() of 0.07). Daily forest water fluxes (E) averaged 2.4 mm d-1 and reached maximums of 4 mm d-1 regularly. Canopy transpiration (Ec) averaged 1.2 mm d-1• Modelled interception accounted for 18% of gross precipitation over the study period. Ec and interception loss (EI) contribute the majority (81%) of the water vapour exchanged between the forest and the atmosphere. E1 accounted for 34% of E and Ec accounted for 47%. Ec was controlled linearly by atmospheric demand (VPD) until a variable transition point was reached, after which mid-day Ec rates remained relatively constant. Ec rates were limited to approximately 0.10 mm hh-1 through the study period. This limitation was sensitive to early morning VPD and soil water deficit. Increases in early morning VPD caused maximum Ec rates to arrive earlier in the day and to be reduced in magnitude. This shift in the timing and magnitude of Ec rates masked a relationship between Ec and soil water content that caused Ec to be strictly limited once root zone soil water content (Bo-25cm) reduced to ~0.07. This study illustrates that the water storage capacities of different site characteristics (particularly the canopy and soil) are an important factor to consider when investigating how changing precipitation characteristics might affect the hydrology of an ecosystem, and discusses the interrelationship between transpiration, soil water supply and atmospheric demand. </p> / Thesis / Master of Science (MSc)

Canonical variate analysis (CVA) is a widely used method for analyzing group structure in multivariate data. It is mathematically equivalent to a one-way multivariate analysis of variance and often goes by the name of canonical discriminant analysis. Change over time is a central feature of many phenomena of interest to researchers. This dissertation extends CVA to longitudinal data. It develops models whose purpose is to determine what is changing and what is not changing in the group structure. Three approaches are taken: a maximum likelihood approach, a least squares approach, and a covariance structure analysis approach. All methods have in common that they hypothesize canonical variates which are stable over time. The maximum likelihood approach models the positions of the group means in the subspace of the canonical variates. It also requires modeling the structure of the within-groups covariance matrix, which is assumed to be constant or proportional over time. In addition to hypothesizing stable variates over time, one can also hypothesize canonical variates that change over time. Hypothesis tests and confidence intervals are developed. The least squares methods are exploratory. They are based on three-mode PCA methods such as the Tucker2 and parallel factor analysis. Graphical methods are developed to display the relationships between the variables over time. Stable variates over time imply a particular structure for the between-groups covariance matrix. This structure is modeled using covariance structure analysis, which is available in the SAS package Proc Calis. Methods related to CVA are also discussed. First, the least squares methods are extended to canonical correlation analysis, redundancy analysis, Procrustes rotation and correspondence analysis with longitudinal data. These least squares methods lend themselves equally well to data from multiple datasets. Lastly, a least squares method for the common principal components model is developed. / Ph. D.