Ecological interactions can play a major role in driving the process of speciation when they lead to a decrease in gene flow between diverging lineages. Various pre- and post-zygotic ecological barriers to gene flow are known to be important in speciation, but the specific barriers that cause the initiation of speciation are often unknown. Phytophagous (plant feeding) insects are powerful systems for evaluating ecologically based reproductive barriers because these organisms generally have a history of traits such as host shifting and host mediated sexual selection associated with speciation. Previous work on the sunflower maggot fly (Strauzia longipennis) indicates that three genetically distinct, diverging varieties co-occur on the host plant Helianthus tuberosus. In this work, I 1) confirm the existence of three diverging varieties by genotyping microsatellite loci, 2) evaluate the presence and strength of three pre-zygotic barriers to reproduction - habitat isolation, pre-mating sexual isolation, and allochronic isolation - between the varieties, and 3) measure the impacts of allochronic isolation on resource partitioning by evaluating host preference, oviposition location, and larval location between diverging Strauzia varieties sharing the same host plant species. I find evidence of pre-mating sexual isolation and allochronic isolation between the three varieties, indicating that these may be reproductive barriers that arise during early stages of divergence. These barriers may have occurred without (or before) the host-shift that is typical of many other diverging phytophagous insect systems. I also find evidence that allochronic isolation leads to resource partitioning of the single host plant resource, which may help the three varieties share the same host plant.

In this project, I profile politically active women in a Muslim society –more specifically in Turkey. I explore the question of how female leaders experience the influence of Islam in contemporary Turkish politics—has had on their understanding(s) of themselves, their public and private lives, their political philosophies and aspirations. In many places around the world, and in a variety of ways, women are constrained from fully participating in political life. The rationale for limiting women's opportunities in the political sphere is often rooted in religion. Religion, or some interpretations thereof, expects them to focus their energies and talents on the private sphere: society can grow and thrive only when women stay home and leave the business of politics to men. Religion, however, often gives women mixed messages about their roles and capacities. Many women take advantage of this ambiguity to interpret their relationship to the realm of politics in creative and sometimes surprising ways. It is important to examine religion's influence on women who are active participants in the public sphere. In this study, utilizing interviews conducted with female members of the Turkish parliament, I show the ways in which women have challenged both the state and religion in order to increase their social and political competence, power, and agency. I find that critical self-reflections of many politically astute Muslim women show that the influences of religion on their consciousness are complex and flexible. Women politicians' constraints in politics derive from cultural, traditional norms rather than religious origins. While some women appear to unconsciously conform to these constraints, majority –if not all, of the women politicians interviewed suggest ongoing efforts to tackle the impositions of the public and private spheres of life.

No description available.

Early phase clinical trials during drug development are vital to the success of an investigational compound. In these phases, an important goal of a dose-finding study is the determination of a dose that is safe and/or effective. Dose-finding trials based on safety outcomes are typically among the first studies conducted for any novel compound. Subsequently, another trial may be conducted to determine which dose among the range of safe doses is the most effective thereby generating a dose-effectiveness profile. When both safety and efficacy are simultaneously considered in a single trial, this is called a phase I/II trial. These trials are advantageous in that they are likely to save both time and resources. This dissertation reviews current phase I/II methods, explores key limitations of these methods, and presents an innovative approach that addresses some of these limitations. The new approaches are compared to one of the most widely known methods of this type. A common phase I/II method is the bivariate Continual Reassessment Method (bCRM; Braun, 2002). The bCRM models dichotomous safety and effectiveness outcomes for use in dose escalation and dose selection decisions. Its overall statistical model is based upon both safety and efficacy models that assume the probabilities of these outcomes increase linearly with dose. The effects of violating the linear monotonicity assumption are explored. It is shown that there are a number of scenarios in which the bCRM performs poorly, including those where effectiveness does not increase beyond a certain dose and when the most efficacious dose is not the highest dose. This indicates that an approach where linearity is not assumed could have great value. The generalized bivariate Continual Reassessment Method (gbCRM) framework is developed as an alternative to dose-finding methods with fixed models. With this approach, the model could be modified to fit a variety of trends that typically arise during dose-finding. It is shown that there are scenarios where the gbCRM provides major advantages when the proper models are used. However, there also exist a number of scenarios where there is an increased risk of choosing an unsafe dose when improper models are used. This study indicates that the use of statistical model selection procedures is likely to improve the performance of the gbCRM by gaining the benefits of proper model selection while avoiding some of the consequences of improper model selection. To address these concerns, an extension of the gbCRM, called the flexible bivariate Continual Reassessment Method (fbCRM), is developed. The fbCRM incorporates model selection and averaging to help make statistical decisions within the gbCRM framework. A simulation study shows that, under many scenarios, the fbCRM is vastly superior to methods with fixed models. Finally, the bCRM, gbCRM and fbCRM are applied to data from a small clinical trial whose goal was to describe the dose-response relationship of the colonization of the Haemophilus influenzae bacterium. These methods are used to define the dose-colonization of this bacterium when applied to human subjects, and to explore how the dose escalation scheme of this trial might have differed if the fbCRM had been used.

The emplacement of tholeiitic magmas along two NE-SW trending rift zones is the dominant mechanism of crustal accretion on Iceland. Small volumes of transitional to alkaline magmas are also erupted through older crust in several off-rift settings, including the Snæfellsnes Peninsula in western Iceland where the basement is formed by 6-8 Ma flood basalts. In this study, we are investigating how these off-rift magmatic plumbing systems compare to those in the main rift zones, given the significant differences in crystal structure and degree of crustal extension, through application of quantitative textural analysis and mineral geothermobarometry. Our focus is Vatnafell, a sub-glacial eruptive unit (414 ± 11 ka) at the western end of the off-rift Ljósufjöll volcanic system in the Snæfellsnes volcanic zone. Samples are highly phyric (∼14% phenocrysts), with large phenocrysts (1-12 mm) of clinopyroxene, olivine, and plagioclase. Crystal size distributions for olivine and clinopyroxene both show kinked profiles, indicating two distinct populations. Glomerocrysts in which large clinopyroxene oikocrysts enclose smaller rounded olivine chadacrysts are common, and a small horizon strongly enriched in large (> 5 mm) olivine and clinopyroxene crystals was found near the base of the unit. These observations suggest incorporation of olivine gabbroic/wehrlitic cumulates by the host magma. Analyses show a bimodal composition for clinopyroxene (cores: mg# 83-88; rims/groundmass mg# 72-77), and calculations suggest crystallization of cores at or near the moho in the deep crust (∼25 km). More extensive analyses of mineral compositions have been used to calculate residence times and ascent rates of the crystalline cargo, and indicate rapid ascent soon after the incorporation of the wehrlitic cumulate. These data have been used to develop a more complete picture of an extension-limited off-rift magmatic plumbing system and allow a more detailed comparison with plumbing systems beneath the extension-dominated main rift zones on Iceland.

Let ƒ be a Maass cusp form for Γ0(N) with Fourier coefficients λƒ(n) and Laplace eigenvalue ¼+k2. For real α≠0 and β>0 consider the sum: ∑nλƒ(n)e(αnβ)Φ(n/X), where Φ is a smooth function of compact support. We prove bounds on the second spectral moment of this sum, with the eigenvalue tending toward infinity. When the eigenvalue is sufficiently large we obtain an average bound for this sum in terms of X. The method is adopted from proofs of subconvexity bounds for Rankin-Selberg L-functions for GL(2)×GL(2). It contains in particular the Kuznetsov trace formula and an asymptotic expansion of a well-known oscillatory integral with an enlarged range of Kε≤L≤K1-ε. The same bounds can be proved in the same way for holomorphic cusp forms. Furthermore, we prove similar bounds for ∑nλƒf(n)λgƒ(n)e(αnβ)Φ(n/X), where g is a holomorphic cusp form. As a corollary, we obtain a subconvexity bound for the L-function L(s, fƒ ×g). This bound has the significant property of breaking convexity even for the trivial bound toward the Generalized Ramanujan Conjecture.

This thesis examines the effects of temperature on the electrochemistry of an aqueous solvent, HNO3, and a non aqueous solvent, acetonitrile and their respective analytes. It has been demonstrated previously that lowering the temperature of a solvent expands the available potential window in which to perform electrochemical experiments. The working window of an aqueous solvent is limited by the electrolysis of water. Cyclic voltammetry was utilized to examine the temperature effects on the rates of the oxidation and reduction of the solvent as well as the effects on the redox species in solution. The redox species experienced decreased peak splitting with lower temperatures, and the diffusion constants and rate constants were lowered as the temperature decreased. It was determined that the solvent window of the HNO3 solution was extended in experiments conducted at lower temperatures. The voltage window went from 2.349 V at 25 °C to 2.671 V at 5 °C. No significant improvement in the voltage window of acetonitrile was seen at lower temperatures. Rate constants for the oxidation and reduction of water were lowered and the voltage window of nitric acid expanded.

Hypertension and type II diabetes are key components of metabolic syndrome affecting one third of US population. Insulin-sensitizing thiazolidinediones (TZDs) are high affinity synthetic ligands for Peroxisome Proliferator-Activated Receptor gamma (PPARG), a nuclear receptor and ligand-activated transcription factor. Clinical data show that TZDs are cardioprotective and lower blood pressure even with increased water and salt retention, suggesting a direct role for PPARG in blood pressure regulation. Human subjects with PPARG mutations exhibit severe early onset hypertension, insulin resistance and type II diabetes. These PPARG mutations, V290M and P467L, affect the ligand-binding domain of PPARG and have dominant negative effect on transcriptional activity. However, the mechanism by which PPARG regulates blood pressure remains elusive. A common feature of hypertension is increased RhoA activity and transgenic mice expressing dominant negative PPARG in vascular smooth muscle cells (S-P467L) exhibit hypertension and severe aortic dysfunction dependent on over-activation of the RhoA/ROCK signaling. Previously published data from our group report that smooth muscle-specific interference of PPARG impairs Cullin-3 E3 ubiquitin ligase-mediated regulation of RhoA and identify Cullin-3 as a novel regulator of vascular function. Patients with de novo mutations that lead to deletion of 57 amino acids encoded by exon 9 in Cullin-3 have early onset hypertension, but the mechanistic basis for this effect is lacking. We show that Cul3 mutation resulted in reduced RhoA ubiquitination and degradation. Reduced Cullin-3 activity increases the RhoA pool that can be activated to a GTP bound state by cellular RhoGEFs in response to contractile agonists promoting hypertension. We have identified a novel PPARG target gene-RhoBTB1, a component of the Cullin-3 RING E3 ubiquitin ligase (CRL3) complex. SiRNA-mediated knockdown of RhoBTB1 significantly decreased Cul3 protein levels resulting in a modest increase in RhoA protein. To understand the fundamental mechanisms by which vascular PPARG regulate vascular function, we generated a transgenic mice with smooth muscle-specific overexpression of RhoBTB1 (S-RhoBTB1) and crossed with the S-P467L mice. We show that replacement of RhoBTB1 in the vascular smooth muscle complements the defects observed in S-P467L due to PPARG interference. This study will advance our understanding on how PPARG regulates blood pressure so that new therapies that maximize the beneficial effects of PPARG can be developed.

Interest among the educational community to measure student academic growth has waxed and waned for more than half a century. The latest surge came with the federal requirement to incorporate growth modeling into assessment systems. Even the Common Core State Standards, intended to make American education globally competitive and prepare children for the twenty-first century, were devised to be more fine-grained and thus align to measure individual growth and produce growth reports that inform instruction and programmatic decisions. However, rather than understanding learning progressions and the underlying constructs that yield actionable growth information, the current core of growth measurement centers around quantifying growth, which has led to an influx of growth models that associate academic progress with percentile ranks. The purpose of this research is to examine the psychometric properties of the assessments from which scores are generated and used in growth models, and highlight test properties that could establish a feedback loop with the potential to inform and improve classroom instruction and development of growth sensitive tests. The primary purpose of this research is to propose a Growth Sensitivity Index (GSI) that gauges the extent to which items capture student academic growth. The second purpose is the estimation of a student-level Growth Score that aids development of actionable growth reports and information. Also discussed is the effect of a test design that relies on overlapping items across adjacent grades, on growth sensitivity of standardized tests using three commonly used normative growth metrics: Student Growth Percentiles (SGPs; Betebenner, 2009), Percentile Rank of Residuals (PRRs; Castellano & Ho, 2013a), and Gain Score Percentile Ranks (GSPRs). Data used for the analyses comes from four tests (mathematics, computation, reading, and vocabulary) and five grade level spans (3-4, 4-5, 5-6, 6-7, and 7-8). The method involves partitioning students' pre- and post-test raw scores based on the (0, 1) response pattern for each item and calculating Growth Sensitivity Index for items and Growth Score for students. This dissertation describes the rationale supporting the proposed methods, followed by illustrative examples. Finally, the use of GSI in test development and Growth Scores for the purposes of generating informative growth reports is discussed. The analysis concluded that using a test with overlapping items in adjacent grades, and including items with high GSIs on tests, could generate growth information directly tied to content that could be used not only to inform instruction and give actionable feedback to teachers, parents, and administrators about student growth, but also aid in the development of growth sensitive tests. Study results also indicate that even though the metric (SGPs, PRRs, and GSPRs) used to estimate student-level growth percentiles is not fundamental, test design in terms of degree of overlapping items across adjacent grades does influence the ability of a test to represent variation in measured growth.

It is said that our visual experience is a ‘Grand Illusion’. Our brains can only process a fraction of the total information available in the natural world, and yet our subjective impression of that world appears richly detailed and complete. The apparent disparity between our conscious experience of the visual landscape and the precision of our internal representation has suggested to some that our brains are equipped with specialized mechanisms that surmount the inherent limitations of our perceptual and cognitive systems. One proposed set of mechanisms, called summary statistics, processes information in a scene by representing the regularities that are often shared among groups of similar in terms of descriptive statistics. For example, snowflakes blowing in the wind may be represented in terms of their mean direction and speed. Prevailing views hold that summary statistics may underlie all aspects of our subjective visual experience, inasmuch as such representations are thought to form automatically across multiple visual fields, exhaustively summarizing all available visual features regardless of attention. We challenge this view by showing that summary statistics are mediated by limited-capacity processes and therefore cannot unfold independently across multiple areas of the visual field. We also show that summary statistics require attention and thus cannot account for our sense of visual completeness outside attended visual space. In light of this evidence, we suggest that the application of summary representations to daily perceptual life has been overstated for the past decade. Indeed, many observations interpreted in terms of summary statistics can be accounted for by alternative cognitive processes, such as visual working memory.