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A 3D meso-scale model is developed to predict the flow of liquid within a semisolid binary Fe-C alloy with various equiaxed microstructure, ranging from dendritic to globular. The model domain consists of a set of 8000 grains given by a Voronoi tessellation. Solidification of each grain is simulated independently via a volume average approach, providing the semi-solid microstructure for the fluid flow simulation. A single domain Darcy-Brinkman model is then used to calculate the resulting pressure field. The model results are found to be in good agreement with the Carman-Kozeny equation for two limiting cases of interfacial area concentration Sv, demonstrating the model’s utility in quantifying permeability of semisolid structures where the fluid flow occurs either in the intra-dendritic (within the envelope enclosed by the dendrite) or extra-dendritic (between dendritic grains) regions. Deviation from Carman-Kozeny behaviour is observed with a transition in microstructure, i.e. when the domain contains a mixture of both dendritic and globular structures or when fluid flow occurs simultaneously in the intra-dendritic and extra-dendritic regions. A permeability microstructure map is created as a function of grain size, secondary dendrite arm spacing, and cooling rate to show the range where the limiting values of Sv are validand, importantly, where they are not. A comparison of the net volumetric inflow caused by shrinkage and deformation is performed, demonstrating that the shrinkage induced by the peritectic transformation is the dominant factor requiring liquid feeding. The present dendritic fluid flow model is useful in the context of multi-physics modelling of defects in peritectic steel grades and other commercially relevant alloys. The authors wish to thank the Natural Sciences and Engineering Research Council of Canada (NSERC) and the McMaster Steel Research Centre for financial support

Teaching science involves more than teaching facts, concepts, principles and theories. Science educators also have a professional obligation to expose students to the values associated with those theories. People make decisions on value-laden, scientific questions from the perspective of their own world view. There should be room in our science curriculum to allow the student to form a personal position on the issues of our day after a fair presentation of the full range of alternatives. Even though the student may already have a firm position on the issue in question, the exercise will foster an understanding of the views of others and promote tolerance for those who differ. One of these issues is that of the origin of life. The objective of this project is to develop a rationale for teaching the full range of alternatives in the science classroom, and to provide a curriculum unit as a resource for teachers who want to give a balanced treatment of the issue in question. Thesis Master of Science (MSc)

Mouse spleen leukocytes were stimulated with phytohemagglutinin and infected with Vesicular Stomatitis Virus. The virus titre from stimulated and unstimulated cells was determined and the number of infected cells in stimulated and unstimulated cultures was examined. Thesis Master of Science (MSc)

Displacement transfer between faults and folds has been extensively documented in the Rocky Mountains as an explanation for structural variability along strike producing seemingly similar overall shortenings. A series of subparallel imbricate thrusts and an associated syncline in the Southern Canadian Front ranges at Heart Mountain has been mapped at a scale of 1:16,667. Megascopic, mesoscopic and microscopic evidence supports the contention that the folding observed at Heart Mountain occurred synchronously with thrusting as the result of displacement transfer from the adjacent thrust. Numerical dynamic analyses (NDA) suggest that twinning of calcite grains occurred very early in the deformational history in response to a regional stress field orientation of 246/03, 340/02, and 159/84 for o 1, o2 , and 03 respectively in the Exshaw plate. Megascopic and mesoscopic fabrics indicate similar results. Ambiguous NDA results for the Heart Mountain Syncline are explained using neutral surface folding theories rather than flexural slip theories generally proposed for folding within the Front Ranges. Neutral surface folds are consistent with the deformational model (displacement transfer) proposed. An orthogonal fracture system is pervasive throughout the thesis area. Observations indicate that fractures are oriented parallel and perpendicular to the strike of the Rocky Mountains. Their development is inferred to have taken place in the same regional stress field thought to be responsible for twinning, with fracture opening occurring after the relaxation of tectonic stresses and the removal of substantial amounts of overburden. Thesis Bachelor of Science (BSc)

In this thesis we develop several approaches to the problem of blind channel equalization based on second-order statistics (808). We consider the single-input singleoutput (8180) system with minimum phase channel where the received signal is sampled at the symbol rate (T-spaced equalizer). We formulate the equalizer design criterion as a simple convex optimization problem, where the equalizer can be obtained efficiently avoiding the local minima problem. We also extend the problem to the single-input multiple-output (8IMO) systems where the received signal is sampled at an integer multiple of the symbol rate. We formulate the problem as a convex optimization problem using the features existing in the channel matrix structure. The problem can be solved efficiently to obtain the equalizer where a global minima is guaranteed. Moreover, we modify this formulation and deduce a closed form solution to the equalizer. Although both methods are sensitive to the channel order as well as existing subspace methods, they perform better than the subspace methods when the channel matrix is close to being singular. Furthermore, we propose an efficient direct minimum mean square error (MM8E) approach to estimate the equalizer. The method does not rely on the channel order and utilizes the channel matrix structure in SIMO systems. Therefore, it outperforms existing algorithms including the previously proposed methods. However, due to the large amount of computations involved in this method we present a new algorithm that belongs to the same class with moderate computational complexity and acceptable performance loss with respect to the latter algorithm. Thesis Master of Applied Science (MASc)

An assessment of what is known about the effective and cost-effective population-level policies to promote healthy eating. The rapid synthesis was conducted to address a question posed by a health system policymaker or stakeholder to the McMaster Health Forum's Rapid Response program. Canadian Partnership Against Cancer

Instructions for setting up the Linux subsystem on Windows 10.

The Middle Devonian Dundee Limestones of Southwestern Ontario accumulated in the Michigan and Appalachian Basins, with deposition in part being controlled by the proximity to the Findlay and Algonquin arches. Six lithofacies were recognized in the Dundee Formation during detailed core and outcrop studies . Stratigraphic relations indicate that, prior to deposition of Dundee carbonates, a major regression exposed underlying Detroit River sediments adjacent to the arches. Subsequent transgression deposited reworked sands and shallow shelf, bioclastic limestones in most areas of the adjoining basins while in westernmost regions of the Appalachian Basin Columbus Formation sediments were accumulating adjacent to the Findlay Arch. Transgression became interrupted during middle Dundee time and a thick unit of lagoonal muds was deposited in the Appalachian Basin. A regionally well-developed firmground capping these mudstones indicates that a significant episode of non-deposition ensued. The equivalents of these muds in the Michigan Basin are pulses of coarse, reworked grainstones and rudstones indicating that substrates there were shallower and above wave base. Evidence of subsequent renewed transgression is preserved as middle to outer shelf moderately fossiliferous mudstones and wackestones overlying shallow shelf facies. Many friends, too many to mention here, made my stay at McMaster an enjoyable one. Mac wouldn't have been the same without the numerous challenges and imaginative adventures in which these people were always willing to participate. Francois Brissette, Bruce Willmer, Randy Meecham, Stu Miller, Steve Beneteau and other members of the Rockbusters Football and Aureoles Baseball teams provided continuous entertainment both on and off of the sports field. Their dedication and light-hearted approach allowed me to maintain a respectable degree of sanity throughout my studies. Finally, I would like to thank my family for their continual assistance, encouragement and support provided during the pursuit of my academic endeavours. Thesis Master of Science (MSc)

Layers of plasticene lubricated with talcum powder were compressed in directions perpendicular to the layering. Normal kink bands oblique to the principal compression direction were produced. These structures were predicted by Cosgrove (1972) after a theory developed by Biot (1965). Other multilayers, with the layering oblique to the principal compression direction, were compressed and these developed instabilities also. The normal kink bands were analysed geometrically. It was found that variation in layer thickness provided the best description and also provided a statement of the state of strain of the final deformation. Thesis Bachelor of Science (BSc)