Translational regulation is an important mechanism for regulating gene expression. Regulation of specific transcripts is often mediated by elements present in the 3′ untranslated region (UTR) of the mRNA. In the Drosophila embryo, translational repression of nanos mRNA is mediated by Smaug protein bound to specific sequences present in the 3′ UTR of the mRNA. Here I show that Smaug recruits Cup protein to the mRNA and that Cup in turn binds to the translation initiation factor eIF4E that is present at the 5′. The interaction between Cup and eIF4E prevents formation of a productive translation initiation complex on the mRNA. Therefore, Smaug-dependent translational repression functions at the initiation step via the indirect interaction of Smaug with eIF4E, which is mediated by Cup. In the second example of translational regulation presented here, I show that an element present in the 3′ untranslated region of the Hsp83 mRNA mediates translational enhancement in the Drosophila embryo. I have identified three proteins, Hrp48, DDP1 and PABP that interact with this element and have demonstrated that Hrp48 and DDP1 function in translational enhancement.

In the past few decades, significant progress has been made in addressing control problems for a variety of engineering systems having smooth dynamics. In practice, one often encounters also non-smooth systems in various branches of science and engineering, such as for example mechanical systems subject to impact. Motivated by the read/write head flying height regulation problem in hard disk drives, where the close proximity of the read/write head to the disk surface results in intermittent contact between the two and a bimodal system behavior, this thesis studies the output regulation problem in switched bimodal linear systems against known and unknown exogenous input signals. The regulation problems in bimodal systems presented in this thesis are solved within sets of Q-parameterized controllers, in which the Q parameters are designed to yield internal stability and exact output regulation in the closed loop switched system. The proposed parameterized controllers are constructed mainly in two steps. The first step is based on constructing a switched observer-based state feedback central controller for the switched linear system. The second step involves augmenting the switched central controller with additional dynamics (i.e. Q parameter) to construct a parameterized set of switched controllers. Based on the proposed sets of Q-parameterized controllers, four main regulation problems are addressed and corresponding regulator synthesis algorithms are proposed. The first problem concerns regulation against known deterministic exogenous inputs, where no stability or structural constraints are imposed on the Q parameter. The second problem is similar to the first, except that the Q parameter is constrained to be a linear combination of basis functions. This structure of the Q parameter is considered in the rest of the thesis. The third problem involves regulation against exogenous inputs involving known deterministic components and unknown random components, and where the regulator is designed subject to an H2 performance constraint. The last problem involves the development of adaptive regulators against unknown sinusoidal exogenous inputs. The different regulator synthesis algorithms are developed based on solving sets of linear matrix inequalities or bilinear matrix inequalities. The last two proposed regulation methods are successfully evaluated on an experimental setup motivated by the flying height regulation problem in hard disk drives, and involving a mechanical system with switched dynamics.

Self-regulation is a highly adaptive process that enables goal-directed behaviour; however, individuals often fail to self-regulate successfully. Failures of self-regulation in the domain of health may be particularly harmful especially for those with chronic diseases. The Energy Model articulated by Baumeister and colleagues proposes that all acts of self-regulation rely on a single, finite energy resource. Thus, one possible explanation for self-regulation failure is insufficient energy. In the current research, four studies examine the relationship between the construct of energy, which can manifest in state or trait form, and self-regulatory success. Past research has demonstrated that individuals who perform two sequential tasks requiring self-regulation perform worse on the second task (the self-regulatory fatigue effect). The Energy Model proposes that this performance decrement can be explained by energy depletion. If this is true, then state energy should mediate the self-regulatory fatigue effect. A series of three experimental studies (studies 1-3) were designed to test this hypothesis. In Study 1, participants were randomly assigned to a gaze regulation task or to a no-regulation control group (as in Schmeichel et. al, 2003) before they watched a brief video clip. Following this first task, all participants worked on a second self-regulatory task (solving anagrams). Persistence and performance on this second task were the dependent measures and energy was measured before and after the initial video task. Contrary to the predictions of the Energy Model, the self-regulatory fatigue effect was not replicated in this study and so the mediating potential of energy could not be tested. However, ratings of task difficulty and effort suggested that individuals in the gaze regulation condition did not find this task to be very challenging. Accordingly, a second study was designed that added an additional level of self-regulatory demand by asking participants to rehearse a 7-digit number during the video clip (memory regulation). When this was crossed with the gaze regulation manipulation, four conditions were created: no regulation, gaze regulation only, memory regulation only and memory + gaze regulation. Study 2 then followed the same approximate procedure as Study 1, with individuals randomly assigned to one of the four conditions. The results of this study were consistent with Study 1 in that the self-regulatory fatigue effect was not replicated. However, the manipulation check suggested that some of the participants in the gaze regulation conditions may not have adhered to experimental instructions and the conditions may have differed in the degree to which they were enjoyable and interesting to participants. Accordingly, a third study used an eye-tracker to assess self-regulation during the video task and evaluated aspects of task engagement. Study 3 followed the same procedures as Study 2. Eye-tracker data verified significant differences between the groups in terms of self-regulation during the initial video task; however, there were no other significant between group differences. Taken together, these 3 studies indicate that the self-regulatory fatigue effect may be less robust than previous research would suggest. An unexpected finding was the high degree of variability in the energy measures, which implied that individual differences in energy may be important to consider. Accordingly, Study 4 prospectively examined the role of dispositional energy in the self-regulation of diet and exercise behaviour by testing whether energy moderated intention-behaviour concordance in a sample of individuals newly diagnosed with Type 2 diabetes. This study demonstrated that energy predicted future exercise behaviour in this sample and provided some preliminary support for the hypothesis that individuals with higher levels of dispositional energy may show more intention-behaviour concordance than those with lower levels of dispositional energy. Overall, these 4 studies provide some tentative support for the role of dispositional energy in the implementation of health behaviour, but do not support the Energy Models predictions regarding self-regulatory fatigue.

For more than a decade, the countries of Central and Eastern Europe and the former Soviet Union have been attempting to transform their centrally planned economies into market economies. In some of these countries a considerably large unofficial economy has become a serious obstacle to economic growth and public finances. Studies by Johnson et al. (1997), Johnson et al. (1998), and Johnson et al. (2000) show that transition countries with large unofficial economies tend to have excessive regulations, high levels of taxation and high incidence of corruption. As well, bureaucratic corruption in tax and customs administration appears to be an important element in defining the underground economy in some transition countries. </p> <p>Given the potential impact of the unofficial economy on public finances and the provision of public goods, the purpose of this dissertation is to examine how corruption affects the unofficial economy in transition countries, with a particular focus on the unofficial economy that results from tax non-compliance. More specifically the study examines tax cheating as it relates to corruption in tax administration, to the business culture in the economy and to the tax-regulation policy-making process. The thesis looks at the feedback effects of decisions of different agents in the economy, and the implications of these decisions for the provision of public goods. </p> <p>The research is conducted along two lines. First, the thesis examines the nature and the extent of corruption in Albania, focusing particularly on the informal sector and corruption in customs and tax administrations. The thesis also examines the implications of the informal economy on the tax revenues available for the provision of public goods. Then the thesis examines the pattern of government spending in public education and transport infrastructure in Albania to reveal the priorities that these sectors are being given during the transition period. Second, the thesis develops a number of theoretical models to examine some of the issues raised in the analysis of Albania. The theoretical models provide a framework to examine the incentives for different agents in the economy to engage in tax cheating and corruption. More specifically, this section of the thesis examines: the feedback effects between the decision of tax inspectors to engage in corruption and firms' cheating activities; the firms' tax compliance as tax cheating and corruption are more accepted practices when they become increasingly widespread; how government affects the degree of cheating and corruption through auditing; and how corruption affects policy-makers' decisions to allocate the revenue obtained from tax collection between public education and infrastructure. </p> <p>Results from the theoretical models show that widespread bureaucratic corruption among tax inspectors can perpetuate an unofficial economy that in turn sustains these and other corrupt practices. In such situations, intense auditing and penalties serve as cheating deterrents only if cheating and engaging in corruption is very costly for both firms and tax inspectors. When cheating becomes cheaper as the size of the unofficial economy grows, a multiplier effect in the economy gives rise to Pareto-ranked multiple equilibria. In an economy with a widespread tolerance for corrupt tax enforcers, tax non-compliance and a low enforcement of penalties, the Pareto inferior (large unofficial economy and an under-provision of public goods) stable equilibrium can prevail. Changes that will move an economy from an inferior equilibrium to a superior equilibrium have a strong political dimension and are complex.</p> <p>Modeling the ways in which policy-makers affect the unofficial economy indicates that, due to the high cost of auditing, the government must allow for some cheating and corruption in order to maximize the revenues available for the provision of public goods. Only if a government views illicit activities as a "public bad", and is willing to eliminate these activities at any cost, will it choose to perform very intense auditing. The government's decision to allocate revenues between education and infrastructure depends on the returns generated by these public goods in the economy and on the private benefits from corruption. A government will allocate funds to education only if education generates relatively higher returns, and if the government favours at the margin the provision of public goods relative to private benefits from corruption. If at the margin the government favours the private benefits from corruption and cheating, then all revenues are allocated to infrastructure even though education generates higher relative returns in the economy. When infrastructure generates higher social returns in the economy, the government commits revenues to infrastructure either to provide the most beneficial public good, or to facilitate opportunities for corruption benefits. Overall the thesis shows that illicit activities (cheating, and political and bureaucratic corruption) can sustain each other regardless which actors in the economy (firms, enforcers, and politicians) undertake them.

A preliminary measure of affect regulation strategies was developed from Parkinson and Totterdell’s (1999) provisional classification of deliberate strategies for improving negative affect. Four broad categories of strategies including Cognitive Engagement, Cognitive Diversion, Behavioural Engagement, and Behavioural Diversion were represented by the measure. Using this measure, relationships between self-reported use of affect regulation strategies and difficulties in emotion regulation and emotion processing variables were investigated. Participants included 186 adults. Participants completed a 20 minute online survey consisting of the measure of affect regulation strategies, the Difficulties in Emotion Regulation Scale (DERS), the Subjective Experience of Emotions Scale (SEE), and a demographic information questionnaire. Weak correlations were found for the majority of the difficulties in emotion regulation and emotion processing subscales and individuals’ self-reported use of affect regulation categories. Results also provide evidence of convergent and discriminant validity for the DERS and SEE.

Vts1p is the Saccharomyces cerevisiae member of the Smaug family of post-transcriptional regulators, which is a group of sequence-specific RNA-binding proteins that regulate target mRNA expression. Vts1p is known to mediate deadenylation-dependent degradation of target transcripts through the recruitment of the Ccr4p/Pop2p/Not deadenylase complex. By conducting a functional analysis of Vts1p deletion mutants, I demonstrate that two regions within Vts1p are independently capable of downregulating the expression of an mRNA reporter. I provide both genetic and biochemical evidence that suggests residues 170-523 regulate reporter expression at the level of mRNA stability and function through a mechanism that requires the Ccr4p/Pop2p/Not deadenylase, whereas residues 1-237 repress reporter expression at the level of translation and function through a novel mechanism. In addition, I map a direct interaction between the eIF4E-binding protein, Eap1p, and the Vts1p SAM domain, which suggests a model in which residues 170-523 recruit Eap1p to mediate efficient target transcript degradation.

Vts1p is the Saccharomyces cerevisiae member of the Smaug family of post-transcriptional regulators, which is a group of sequence-specific RNA-binding proteins that regulate target mRNA expression. Vts1p is known to mediate deadenylation-dependent degradation of target transcripts through the recruitment of the Ccr4p/Pop2p/Not deadenylase complex. By conducting a functional analysis of Vts1p deletion mutants, I demonstrate that two regions within Vts1p are independently capable of downregulating the expression of an mRNA reporter. I provide both genetic and biochemical evidence that suggests residues 170-523 regulate reporter expression at the level of mRNA stability and function through a mechanism that requires the Ccr4p/Pop2p/Not deadenylase, whereas residues 1-237 repress reporter expression at the level of translation and function through a novel mechanism. In addition, I map a direct interaction between the eIF4E-binding protein, Eap1p, and the Vts1p SAM domain, which suggests a model in which residues 170-523 recruit Eap1p to mediate efficient target transcript degradation.

A preliminary measure of affect regulation strategies was developed from Parkinson and Totterdell’s (1999) provisional classification of deliberate strategies for improving negative affect. Four broad categories of strategies including Cognitive Engagement, Cognitive Diversion, Behavioural Engagement, and Behavioural Diversion were represented by the measure. Using this measure, relationships between self-reported use of affect regulation strategies and difficulties in emotion regulation and emotion processing variables were investigated. Participants included 186 adults. Participants completed a 20 minute online survey consisting of the measure of affect regulation strategies, the Difficulties in Emotion Regulation Scale (DERS), the Subjective Experience of Emotions Scale (SEE), and a demographic information questionnaire. Weak correlations were found for the majority of the difficulties in emotion regulation and emotion processing subscales and individuals’ self-reported use of affect regulation categories. Results also provide evidence of convergent and discriminant validity for the DERS and SEE.

Translational regulation is an important mechanism for regulating gene expression. Regulation of specific transcripts is often mediated by elements present in the 3′ untranslated region (UTR) of the mRNA. In the Drosophila embryo, translational repression of nanos mRNA is mediated by Smaug protein bound to specific sequences present in the 3′ UTR of the mRNA. Here I show that Smaug recruits Cup protein to the mRNA and that Cup in turn binds to the translation initiation factor eIF4E that is present at the 5′. The interaction between Cup and eIF4E prevents formation of a productive translation initiation complex on the mRNA. Therefore, Smaug-dependent translational repression functions at the initiation step via the indirect interaction of Smaug with eIF4E, which is mediated by Cup. In the second example of translational regulation presented here, I show that an element present in the 3′ untranslated region of the Hsp83 mRNA mediates translational enhancement in the Drosophila embryo. I have identified three proteins, Hrp48, DDP1 and PABP that interact with this element and have demonstrated that Hrp48 and DDP1 function in translational enhancement.

In the past few decades, significant progress has been made in addressing control problems for a variety of engineering systems having smooth dynamics. In practice, one often encounters also non-smooth systems in various branches of science and engineering, such as for example mechanical systems subject to impact. Motivated by the read/write head flying height regulation problem in hard disk drives, where the close proximity of the read/write head to the disk surface results in intermittent contact between the two and a bimodal system behavior, this thesis studies the output regulation problem in switched bimodal linear systems against known and unknown exogenous input signals. The regulation problems in bimodal systems presented in this thesis are solved within sets of Q-parameterized controllers, in which the Q parameters are designed to yield internal stability and exact output regulation in the closed loop switched system. The proposed parameterized controllers are constructed mainly in two steps. The first step is based on constructing a switched observer-based state feedback central controller for the switched linear system. The second step involves augmenting the switched central controller with additional dynamics (i.e. Q parameter) to construct a parameterized set of switched controllers. Based on the proposed sets of Q-parameterized controllers, four main regulation problems are addressed and corresponding regulator synthesis algorithms are proposed. The first problem concerns regulation against known deterministic exogenous inputs, where no stability or structural constraints are imposed on the Q parameter. The second problem is similar to the first, except that the Q parameter is constrained to be a linear combination of basis functions. This structure of the Q parameter is considered in the rest of the thesis. The third problem involves regulation against exogenous inputs involving known deterministic components and unknown random components, and where the regulator is designed subject to an H2 performance constraint. The last problem involves the development of adaptive regulators against unknown sinusoidal exogenous inputs. The different regulator synthesis algorithms are developed based on solving sets of linear matrix inequalities or bilinear matrix inequalities. The last two proposed regulation methods are successfully evaluated on an experimental setup motivated by the flying height regulation problem in hard disk drives, and involving a mechanical system with switched dynamics.