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The effects of education can shape a multitude of elements throughout our society from poverty to technology. Elementary school students come into a classroom under the influence of what they have learned at home and out in the community. Because of so many different conditions that children live among, their knowledge is varied, and their rates of learning are contrasting. There is no one size fits all teaching method that will work for everyone. Therefore, teachers must use best practices, such as formative assessment, along with differentiated instruction in order to provide ways for all learners to show growth. This was a study of how teachers use formative assessment in the classroom and the effects of formative assessment on students' motivation, self-efficacy, and self-regulated learning. It was also an observation of the methods teachers utilized to reflect on their instructional practices. Findings showed that teacher participants demonstrated coaching skills with their students to help them progress towards greater student reflection. Second, with the implementation of student-centered tasks, there was an increase in student motivation which led to classroom engagement. Finally, teachers practiced reflection on their teaching with informal methods. It was recommended that elementary school teachers provide students with the means to give feedback on their own learning such as using feedback rubrics that contain clear criteria for meeting goals. A suggestion was also discussed to implement structured professional learning communities for teachers to share detailed ideas on instruction and guide their colleagues with specific examples that would be relevant to their immediate teaching. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

So often in astronomy, an object is not considered for its individual merits, but for what we may learn from its properties regarding some larger population. The existence of dark matter is a prime example of this; we cannot see it directly but we can infer its presence by noting its effects on the stars orbiting within its potential. This thesis describes how various sets of tracer populations can be used to probe the properties of a variety of galaxies in the Local Group. I begin by describing the extraction of a variable catalogue from the Sloan Digital Sky Survey Stripe 82 dataset and then use the catalogue to select a high-quality set of RR Lyrae stars. Analysing the distribution of the RR Lyraes reveals three significant substructures in the Milky Way halo: the Hercules-Aquila Cloud and the Sagittarius Stream, which were already known to exist, and the Pisces Overdensity, which was previously undetected. It is a faint, extended structure found at ~80 kpc and is of unknown origin. Altogether, I find that nearly 80% of the RR Lyraes are associated with substructures, consistent with the theory that galaxy halos are predominantly, or even entirely, made up from disrupted satellites. I also investigate the density distribution of RR Lyraes in the halo, finding that it is best fit by a broken-power-law model, in good agreement with previous work. I go on to develop a set of tracer mass estimators that build on previous work which make use of actual (and not projected) distance and proper motion data, reflecting the amount and quality of data now available to us. I show that proper motion data is, in theory, very useful and can greatly increase the accuracy of the mass estimates; in practice, however, current analysis is hampered by the large errors inherent in the proper motion data. The results are also subject to mass-anisotropy degeneracy, which current data is not yet able to break. Nevertheless, I am able to estimate the mass of the Milky Way to be M = 2.7 ± 0.5 x 10¹² Msun and the mass of M31 to be M = 1.5 ± 0.4 x 10¹² Msun. Andromeda XII and Andromeda XIV are two M31 satellites that have been dubbed 'extreme' and are thought to be on first infall into the M31 system. I modify the classical Timing Argument so that it can be applied to two external galaxies and then apply it to M31 and each of And XII and And XIV in turn to investigate the properties of their orbits. I then run a series of Monte Carlo simulations to investigate how likely such satellites are to exist and conclude that they are not as unusual as previously believed. Finally, I discuss three upcoming wide-field, all-sky surveys and their implications for the future of the study of the Local Group.

Proton transport (PT) in biomolecular systems is the controlled movement of hydrogen ions across a cellular membrane, frequently through a channel or transporter, and is essential for sustaining life. PT is necessary for a variety of functions including maintaining pH gradients, driving ATP synthesis, and facilitating the co- or anti-transport of other small molecules, among many others. Because of their crucial role, protein channels and transporters are often chosen as drug targets in bacteria or viruses that cause disease. Thus, beyond elucidating PT mechanisms to understand how a specific channel or transporter works, studying the detailed interactions that facilitate PT is critical as it can inform drug design efforts to help treat disease, and it can reveal fundamental principles of PT that can then be used to control this function in designed systems. In this thesis, I use computer simulation to study processes of PT in two systems, the influenza A M2 channel and two de novo designed proteins. Through three different projects focused on M2, I provide a detailed view on PT in M2, deducing important interactions and providing insight into inhibitor binding. First, using extensive Multiscale Reactive Molecular Dynamics (MS-RMD) simulations with explicit Grotthuss-shuttling hydrated excess protons, I show how a hydrated excess proton strongly influences both the protein and water hydrogen-bonding network throughout the channel, providing further insight into the channel’s acid-activation mechanism and rectification behavior. Second, I extend this work to focus on inhibitor binding. In this work, I illuminate a dynamic understanding of the mechanism of drug inhibition in M2, grounded in the fundamental properties that enable the channel to transport and stabilize excess protons, with critical implications for future drug design efforts. Third, I use combined MS-RMD and quantum mechanics/molecular mechanics simulations to calculate the potential of mean force (PMF) of PT in a prominent mutant of M2, showing how the D44N mutation alters the free energy and mechanism of PT. Finally, I use these methods to study two de novo designed proteins in collaboration with experimental experts in protein design. In this work, our collaborators find that introducing a single polar residue into an otherwise hydrophobic channel is sufficient to induce proton conduction. Using MS-RMD simulations, I calculate 2D PMFs of PT for two systems, one with the mutation and one without, to understand how the mutation facilitates PT. This work reveals fundamental characteristics of PT and provides insight into how it can be harnessed in future protein design. Altogether, the work in this thesis presents a dynamic picture of proton transport in proteins and reveals key characteristics that are critical for understanding PT in biological systems overall, with implications for future drug design efforts and de novo protein design.

Intimate partner aggression (IPA) is a serious national health concern that affects an alarming number of individuals and can lead to substantial psychological and physical suffering. Situational risk factors that arise in the immediate context of IPA reflect state-like influences that trigger aggression. Because these factors are more variable and fluctuate according to the situation, they are potentially promising targets for prevention and intervention efforts (e.g., through cognitive and behavioral interventions). Within this realm, two factors in particular appear to play a prominent role in the etiology of IPA: alcohol intoxication and cognitive emotion regulation strategies. In contrast to prior correlational work, the present study experimentally manipulated alcohol consumption and emotion regulatory strategies to assess their individual and combined effects on IPA, which was measured both observationally and through self-report. It was expected that both alcohol intoxication and anger rumination would increase IPA perpetration, whereas reappraisal would result in decreased IPA perpetration. Further, intoxication and emotion regulation strategies were expected to have interactive effects on IPA perpetration such that rumination would enhance associations between alcohol intoxication and aggression, whereas reappraisal would attenuate the relationship between alcohol and IPA perpetration. Hypotheses for the study were partially supported. Findings show that participants in the alcohol condition generally displayed greater IPA than participants in the placebo condition. Emotion regulation strategy condition was not found to affect IPA. When examining only the effects of alcohol and emotion regulation strategy condition, emotion strategy use did not moderate the relationship between alcohol intoxication and IPA. However, alcohol and emotion regulation strategy conditions were found to interact with trait levels of rumination and reappraisal to predict IPA. The implications of these results, future directions for research, and implications for IPA intervention and prevention strategies are discussed. Adviser: David DiLillo