No description available.

The Design of an experiment involves selection of levels of one or more factor in order to optimize one or more criteria such as prediction variance or parameter variance criteria. Good experimental designs will have several desirable properties. Typically, one can not achieve all the ideal properties in a single design. Therefore, there are frequently several good designs and choosing among them involves tradeoffs. This dissertation contains three different components centered around the area of optimal design: developing a new graphical evaluation technique, discussing designs for non-regular regions for first order models with interaction for the two- and three-factor case, and using the standard designs in the case of generalized linear models (GLM). The Fraction of Design Space (FDS) technique is proposed as a new graphical evaluation technique that addresses good prediction. The new technique is comprised of two tools that give the researcher more detailed information by quantifying the fraction of design space where the scaled predicted variance is less than or equal to any pre-specified value. The FDS technique complements Variance Dispersion Graphs (VDGs) to give the researcher more insight about the design prediction capability. Several standard designs are studied with both methods: VDG and FDS. Many Standard designs are constructed for a factor space that is either a p-dimensional hypercube or hypersphere and any point inside or on the boundary of the shape is a candidate design point. However, some economic, or practical constraints may occur that restrict factor settings and result in an irregular experimental region. For the two- and three-factor case with one corner of the cuboidal design space excluded, three sensible alternative designs are proposed and compared. Properties of these designs and relative tradeoffs are discussed. Optimum experimental designs for GLM depend on the values of the unknown parameters. Several solutions to the dependency of the parameters of the optimality function were suggested in the literature. However, they are often unrealistic in practice. The behavior of the factorial designs, the well-known standard designs of the linear case, is studied for the GLM case. Conditions under which these designs have high G-efficiency are formulated. / Ph. D.

Traditional single stage design optimality procedures can be used to efficiently generate data for an assumed model y = f(x^(m),b) + ε. The model assumptions include the form of f, the set of regressors, x^(m) , and the distribution of ε. The nature of the response, y, often provides information about the model form (f) and the error distribution. It is more difficult to know, apriori, the specific set of regressors which will best explain the relationship between the response and a set of design (control) variables x. Misspecification of x^(m) will result in a design which is efficient, but for the wrong model. A Bayesian two stage design approach makes it possible to efficiently design experiments when initial knowledge of x^(m) is poor. This is accomplished by using a Bayesian optimality criterion in the first stage which is robust to model uncertainty. Bayesian analysis of first stage data reduces uncertainty associated with x^(m), enabling the remaining design points (second stage design) to be chosen with greater efficiency. The second stage design is then generated from an optimality procedure which incorporates the improved model knowledge. Using this approach, numerous two stage design procedures have been developed for the normal linear model. Extending this concept, a Bayesian design augmentation procedure has been developed for the purpose of efficiently obtaining data for variance modeling, when initial knowledge of the variance model is poor. / Ph. D.

Electric and more-electric vehicle proliferation continues unabated as government mandates worldwide demand fuel economies in excess of what conventional internal combustion engines are capable of. Vehicle electrification, to any degree, is perceived to be the means by which automotive companies may meet these targets. Electrification introduces a myriad of problems including cost, weight and reliability, all of which must be addressed in their own right. The rapid commercialisation of wide-bandgap semiconductor materials which, as a whole, exhibit properties superior to ubiquitous Silicon, provides the opportunity for power electronic converter minimisation and efficiency maximisation, easing the challenge of meeting current and incoming standards. This thesis concerns itself with the design methodology of a highly power dense converter, as applied to a three-phase inverter. By using figures of merit, simple modelling techniques and novel discrete component selection tools, a converter is designed that is capable of switching 30kW of electric power at 100kHz in a small package. Testing results show that the converter, with a simple forced air heatsinking solution, can effectively switch 9kW of power and is capable of reaching 15kW. Given the temperature rise of one phase leg of the inverter relative to the others, a superior heatsink design would allow the inverter to reach its rated power levels. / Dissertation / Master of Applied Science (MASc)

<p> This dissertation consists of three essays that evaluate long-term agricultural projections. The first essay focus on evaluating Congressional Budget Office’s (CBO) baseline projection of United States Department of Agriculture (USDA) mandatory farm and nutrition programs. The second essay examine USDA soybean ending stock projections, and the third essay investigate impact of macroeconomic assumptions on USDA’s baseline farm income projections.  We use publicly available data from Congressional Budget Office (CBO) and United States Department of Agriculture (USDA)</p>

Liquid-liquid phase separation (LLPS) has been proposed as the underlying physical principle leading to the formation of membrane-less organelles in eukaryotic cells, following advancements, in the last two decades, in experimental observations owing to progress in confocal microscopy. These organelles can act as compartments in sequestering molecules and tuning rates of biochemical reactions, among a repertoire of functions they serve. Biochemical reactions are constantly in progress in living cells and are driven out of equilibrium due to fuel consumption in the form of ATP or GTP molecules. Free diffusion of reactive molecules through these compartments leads to their spatiotemporal sequestration and automatically implies an interplay between phase separation and chemical reactions. In this work, we are specifically interested to understand how the two processes closely affect each other and applying the understanding to tune better bottom-up design principles for synthetic life, which involves coupling compartmentalization and chemical reactions. The first part of this work is devoted to studying the interplay between phase separation and chemical reactions. To this end, we developed the theory of mass action kinetics of equilibrium and out-of-equilibrium processes occurring at phase equilibrium in a multicomponent mixture. Phase equilibrium is imposed at all times, thus restricting the chemical kinetics to the binodal manifold. We learn more about circumstances in which reaction rates can differ in coexisting phases. Next, we decouple the phase-forming components (scaffolds) and the dilute reactive components (clients), which means that the reactive dilute components respond to the heterogeneous profile in the system set by the scaffold but do not affect it. This allows us to investigate to what extent compartments can affect chemical reactions in terms of their yield at steady state for a bimolecular reaction or initial reaction rate for a nucleation process compared to the absence of compartments. We use the effective droplet model and mass reaction kinetics at phase equilibrium to address the above questions. We can understand better how the properties of reactions can be optimally tuned by compartment size. Following the theoretical developments in the first part of this work, we proceed to use the theoretical model of mass action kinetics at phase equilibrium to study emergent properties of parasitic behavior in a system composed of multiple fuel-driven reaction cycles, which lead to the formation of so-called 'building blocks' which can phase separate. This study also helps us probe the buffering capacity of phase separation. It further provides insights into how the lifetime of reactive 'building blocks' can be tuned via phase separation. Synthetic cells are generally realized by localizing minimalistic reactions in micron-scale water-filled environments, thus mimicking compartmentalization. Here we apply our model to understand how the localization of an autocatalytic process (PEN-DNA reaction) inside proteinosomes affect the reaction rates compared to the reactions in a homogeneous buffer solution. To summarize, we developed theoretical approaches to study the interplay of chemical reactions with compartmentalization and apply such approaches to systems chemistry and synthetic biology experimental studies to unravel how reactions can be controlled through compartmentalization.:1 Introduction 1 1.1 Phase Separation - A brief overview of the development of the field . . . . . . 1 1.2 Thermodynamics of phase separation in a multi-component mixture . . . . . 4 1.2.1 Mean field free energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2.2 Other possible free energy considerations: Beyond mean-field . . . . . 7 1.2.3 Exchange chemical potential, chemical activity and osmotic pressure . 8 1.2.4 Thermodynamic instability leads to phase separation . . . . . . . . . 9 1.2.5 Phase equilibrium conditions . . . . . . . . . . . . . . . . . . . . . . . 10 1.2.6 Relaxation dynamics to phase equilibrium . . . . . . . . . . . . . . . . 13 1.3 Thermodynamics of chemical reactions in homogeneous mixtures . . . . . . . 14 1.3.1 Chemical equilibrium conditions . . . . . . . . . . . . . . . . . . . . . 14 1.3.2 Relaxation to chemical equilibrium . . . . . . . . . . . . . . . . . . . . 16 1.4 Thermodynamic equilibrium . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 1.5 Scope of the thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2 Chemical reaction kinetics at phase equilibrium 21 2.1 Kinetics of chemical reactions relaxing to thermodynamic equilibrium . . . . 21 2.1.1 Volume fraction field and phase volume kinetics . . . . . . . . . . . . 22 2.1.2 Diffusive exchange rates between phases . . . . . . . . . . . . . . . . . 22 2.1.3 Reaction rates at phase equilibrium . . . . . . . . . . . . . . . . . . . 23 2.1.4 Properties of chemical reactions at phase equilibrium . . . . . . . . . 24 2.2 Unimolecular chemical reactions in coexisting phases . . . . . . . . . . . . . . 25 2.3 Bimolecular chemical reactions in coexisting phases . . . . . . . . . . . . . . . 27 2.4 Chemical reactions maintained away from chemical equilibrium . . . . . . . . 28 2.4.1 Tie-line selecting curve . . . . . . . . . . . . . . . . . . . . . . . . . . 31 2.5 Summary and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 3 Chemical reactions of dilute clients in phase-separated compartments 33 3.1 Thermodynamics of a multicomponent mixture of scaffold and clients . . . . 34 3.1.1 Phase equilibrium conditions: Dilute client limit . . . . . . . . . . . . 35 3.1.2 Relaxation dynamics to phase equilibrium: Dilute client limit . . . . . 38 3.1.3 Chemical equilibrium conditions: Dilute client limit . . . . . . . . . . 40 3.1.4 Relaxation dynamics to chemical equilibrium: Dilute client limit . . . 41 3.2 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3.2.1 Two-state transitions controlled by a drop . . . . . . . . . . . . . . . . 43 3.2.2 Bimolecular reaction controlled by a drop . . . . . . . . . . . . . . . . 45 3.2.3 Nucleation reaction controlled by a drop . . . . . . . . . . . . . . . . . 47 3.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 4 Fuel-driven chemical reactions in the dilute phase at phase equilibrium 50 4.1 Chemical reaction network and its properties . . . . . . . . . . . . . . . . . . 51 4.1.1 Observations from individual reaction cycles . . . . . . . . . . . . . . 52 4.1.2 Observations from combined reaction cycles . . . . . . . . . . . . . . . 53 4.2 Kinetic equations at phase equilibrium . . . . . . . . . . . . . . . . . . . . . . 55 4.3 Construction of the ternary phase diagram . . . . . . . . . . . . . . . . . . . . 57 4.4 Mechanism of co-phase separation . . . . . . . . . . . . . . . . . . . . . . . . 58 4.4.1 Composition of droplets . . . . . . . . . . . . . . . . . . . . . . . . . . 60 4.5 Co-phase separation with periodic fueling . . . . . . . . . . . . . . . . . . . . 61 4.6 Effects of activation rate constants on host-parasite identity . . . . . . . . . . 63 4.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 5 Study of enzymatic kinetics in compartmentalized systems 65 5.1 Autocatalytic reactions and their properties . . . . . . . . . . . . . . . . . . . 66 5.2 PEN DNA mass action kinetics . . . . . . . . . . . . . . . . . . . . . . . . . . 67 5.3 Proteinosomes affect the PEN DNA reactions . . . . . . . . . . . . . . . . . . 70 5.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 6 Conclusion and Outlook 72 A Free energy calculations for block charged polymers using RPA 76 B Numerical Methods 79 C Linear first order corrections to scaffold equilibrium volume fractions 83 D Dynamic equations in dilute limit 86 E Spatial solutions 88 F Fitting routine and extracted rate coefficients 90 G Experimental methods 95 H Calibration constants and reaction rate coefficients of PEN DNA study 98 List of figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

No description available.

No description available.

No description available.

No description available.