Through the use of the interpretive lenses of sociology of news, identity, and community roles, this research aims to understand the approach to journalism by small-town weekly newspapers. The research explores how small-town weekly newspapers in rural America are faring in the current emergent media environment. Are these newspapers surviving the digital age or are they experiencing the similar hardships larger daily newspapers are facing, including revenue and circulation declines, and in some cases product elimination? The research also investigates whether or not the small-town journalism approach is different than it is for larger daily newspapers by theoretically and conceptually examining the routine practices of news gathering used by news workers, the identity formations of weekly newspaper journalists, and the journalists’ and community members’ perceptions of the weekly newspaper’s role in the community. To accomplish this, the researcher has used quantitative and qualitative research techniques, including a large-scale survey directed at weekly newspaper publishers, a thematic content analysis of weekly newspaper content, and in-depth interviews with news workers and community members, to conduct an analysis of news production in small towns in Iowa. Focusing on small-town weekly newspapers is crucial because the close, frequent and often personal interactions of small-town journalists with their audiences create the potential for a more direct effect on community members’ everyday lives. In addition to contributing to the understanding of small-town community news production, this research offers news industry leaders and practitioners insight into a different, more personally engaged, approach to journalism.

Ion pumps establish homeostasis across the membranes of living cells. Hearing is a mechanotransduction event that takes place in a closed compartment containing a fluid high in K+ concentrations. In Drosophila melanogaster, this closed compartment is formed by a scolopale cell that wraps around the dendrite of sensory neurons. The receptor lymph is maintained by the scolopale cell. The lumenal membrane of the scolopale cell is the wall of the compartment containing the receptor lymph, the scolopale space. The ablumenal membrane of the scolopale cell creates the border of the scolopidium. The Na/K pump is located on the ablumenal membrane of the scolopale cell, bringing K+ into the scolopale cell cytoplasm and extruding K electrogenically (Roy et al, 2013). We explored other primary and secondary ion pumps that are involved in creating a K+-rich lumen in the Malpighian tubule (Day et al, 2008; Rodan et al, 2012). We used RNAi technology to knockdown one gene at a time and electrophysiology to measure a sound evoked potential (SEP) that reflects the fly’s ability to hear. We found that knocking down V-ATPase, a proton pump, subunits involved in proton extrusion significantly reduces the SEP of knockdown flies. The involvement of cation chloride cotransporters (CCCs) and cation proton antiporter (CPAs), both secondary ion pumps that use the gradients created by the Na/K pump and V-ATPase respectively to pump other ions up their gradient, is less clear. We found that knocking down Nhe3, a CPA, significantly reduced the SEP when knocked down in the scolopale cell, suggesting it as a partner to the V-ATPase. Knocking down CG31547, a CCC, statistically increased the SEP, possibly a type1 statistical error.

This study focuses on developing a book arts curriculum as a tool for teaching about creativity and problem solving. The curriculum's ultimate goal is to introduce and emphasize book arts as an expressive and powerful medium to future teachers and artists. Book arts will be used to offer potentialities for collaborative, learner-centered instruction. Students will create structures and artists' books from their experience, their learning will emerge from personal interactions with the structures and artists' books presented. The curriculum is planned into three modules, each module containing a different set of projects and activities organized to scaffold students learning in an engaging process. The modules examine book structures, artists' books, and a project that can either further explore book structures and artists books, or it can explore incorporating some other aspect of book arts in the project. Each module provides a broad range of examples, discussions, questions, and applications.

CT is a powerful method for noninvasive assessment of the lung. Advancements to CT technology have guided the high-resolution structural and functional assessment of lung diseases. This has helped make the transition from characterizing the severity of lung disease to novel phenotyping of disease subtypes. Chronic obstructive pulmonary disease (COPD) is a spectrum of inflammatory lung disease affecting lung parenchyma, airways, and the pulmonary and systemic vasculature. Quantitative CT-based measures have largely focused on quantifying the extent of airway and parenchymal damage with disease. Recently perfusion CT method has been used to assess the pulmonary vascular bed. This technique was used to demonstrate a vascular etiology of smoking-associated centriacinar emphysema (CAE), a subtype of the COPD spectrum. However, technical challenges have limited the transition of this CT method to clinical studies to assess pulmonary vascular physiology. In this thesis, we introduce dual energy CT-perfused blood volume (DECT-PBV) as a novel image-based biomarker to assess peripheral pulmonary vascular dysfunction. Using this technique, we show that smoking-associated pulmonary perfusion heterogeneity, a marker of abnormal blood flow is a reversible process, in the midst of smoking-associated lung inflammation, and not a product of advanced lung disease. We demonstrate, via regional PBV measures and structural measures of the central pulmonary vessels, that the reversibility of pulmonary perfusion heterogeneity is a direct result of increased peripheral (downstream) parenchymal perfusion. We validate our quantitative imaging approach in a unique cohort of early CAE-susceptible smokers using a pharmaceutical intervention to dilate the pulmonary parenchymal vascular bed. The validated DECT approach and our novel DECT imaging findings extend our characterization of the vascular phenotype in inflammatory lung disease and provide a framework for future quantitative imaging studies of the lung to assess early intervention targeted to pulmonary vessels.

The use of a system of detention reservoirs distributed across a region has been gaining interest as an innovative way to manage riverine flooding. An open problem is the role played by the spatial configuration of detention projects in regulating the flow. Possible locations for reservoirs within a watershed are numerous, however methods used in literature to place reservoirs on real watersheds and couple them with realistic values of storage are not very detailed. This thesis presents a methodology for modeling dams and related reservoirs at high density, based on the analysis of a Digital Elevation Model (DEM) of the terrain, and extracting their geometric characteristics. Four indicators, based on the morphology of reservoirs and their position in the network, are proposed to classify them and identify which locations are more suitable for a detention project. These are the Horton order, the ratio between volume and extent of the reservoir, the ratio between volume and the expected inflow volume, and the volume itself. The study area of the analysis is the Turkey River watershed, in northeastern Iowa. The algorithm analyzed over 100,000 locations and successfully modeled more than 60%. Most of the failed attempts occurred in a region of the watershed where the terrain is generally flat and reservoirs, when feasible, tend to store water inundating a large area. Regional patterns of ratios are highlighted at the scale of the watershed, but no clear, recurring pattern is identified at the subwatershed level. The considered indicators have the purpose of narrowing down locations to a manageable number of candidates. Further criteria can also be adopted, based on land use and social and economic considerations. Selected reservoirs can be variously combined and entered, together with their geometric characteristics, in hydrological models and optimization processes to determine the best spatial configuration possible.

This dissertation examines streaming media both as a technological innovation and cultural practice that co-configures audience and industry. Strategies and tactics provide a theoretical framework for understanding streaming media. Streaming is theorized as a tactic; wherein audiences momentarily buck against the strategic logic of media conglomerates and copyright regimes. However, streaming, concomitantly, is an audience tactic and a strategic logic of an emergent streaming industry. This results in the blurring between first and third party and sanctioned and unsanctioned streaming. In this dissertation, I parse out what are the nascent streaming logics within this burgeoning industry and how they constitutively shape and re-shape audiences and traditional broadcasting logics. Five typologies of streaming serve as conceptual tools for deepening our understanding of streaming media and technology. The first is streaming as a recent technological advancement, divided into software and hardware categories. The second conceptual framework is a typology of streaming that divides streaming into first and third party sanctioned and unsanctioned streaming. The third is streaming as an emergent industry. The fourth is streaming as a discourse, and the final typology divides streaming based on geography as transnational streaming, national streaming, and diasporic streaming. All of these classifications lay the groundwork for the further conceptualization of this important and emergent socio-technical practice.

As the use of technology for personal, professional, and learning purposes increases, more and more assessments are transitioning from a traditional paper-based testing format to a computer-based one. During this transition, some assessments are being offered in both paper and computer formats in order to accommodate examinees and testing center capabilities. Scores on the paper-based test are often intended to be directly comparable to the computer-based scores, but such claims of comparability are often unsupported by research specific to that assessment. Not only should the scores be examined for differences, but the thought processes used by raters while scoring those assessments should also be studied to better understand why raters might score response modes differently. Previous comparability literature can be informative, but more contemporary, test-specific research is needed in order to completely support the direct comparability of scores. The goal of this thesis was to form a more complete understanding of why analytic scores on a writing assessment might differ, if at all, between handwritten and typed responses. A representative sample of responses to the writing composition portion of a large-scale high school equivalency assessment were used. Six trained raters analytically scored approximately six-hundred examinee responses each. Half of those responses were typed, and the other half were the transcribed handwritten duplicates. Multiple methods were used to examine why differences between response modes might exist. A MANOVA framework was applied to examine score differences between response modes, and the systematic analyses of think-alouds and interviews were used to explore differences in rater cognition. The results of these analyses indicated that response mode was of no practical significance, meaning that domain scores were not notably dependent on whether or not a response was presented as typed or handwritten. Raters, on the other hand, had a more substantial effect on scores. Comments from the think-alouds and interviews suggest that, while the scores were not affected by response mode, raters tended to consider certain aspects of typed responses differently than handwritten responses. For example, raters treated typographical errors differently from other conventional errors when scoring typed responses, but not while scoring the handwritten duplicates. Raters also indicated that they preferred scoring typed responses over handwritten ones, but felt they could overcome their personal preferences to score both response modes similarly. Empirical investigations on the comparability of scores, combined with the analysis of raters’ thought processes, helped to provide a more evidence-based answer to the question of why scores might differ between response modes. Such information could be useful for test developers when making decisions regarding what mode options to offer and how to best train raters to score such assessments. The design of this study itself could be useful for testing organizations and future research endeavors, as it could be used as a guide for exploring score differences and the human-based reasons behind them.

College decisions are often the result of a variety of influences related to student background characteristics, academic characteristics, college preferences and college aspirations. College counselors recommend that students choose a variety of schools, especially schools where the general student body matches the academic achievement of students. These types of schools are generally referred to as match schools. This thesis examined the initial college decisions of high school students in a large Midwestern state, who were an academic match for selective and highly selective schools by observing the student characteristics that were most influential in predicting college matching for students’ initial first choice institution. This thesis also observed college enrollment among students who chose a match school as their first choice institution, college matching over a time period from 1992 to 2013, and college matching after the implementation of a state initiative designed to help students apply for college. Logistic regression along with descriptive statistics were used as the primary analyses for college matching. Results from these analyses showed that students belonging to underrepresented minority groups had odds of college matching for their first choice institution that were significantly greater than white students. Students whose parents earned at least a bachelor’s degree had odds that were significantly greater than students whose parents had not earned a bachelor’s degree. Also, students whose coursework included calculus and physics, and students who planned to earn a graduate degree had significantly greater odds of matching on their first choice institution than students who were not a part of these respective groups. Among students in the sample who chose a match school for their first choice institution, students who had at least one parent earn up to a bachelor’s degree were significantly more likely to enroll in a match school. Also, the percentage of students at a single high school who were eligible for free and reduced lunch were negatively associated with the odds of students enrolling in a match school. To observe score sending among students to their first choice institution over time an additional variable, “year” was added to the logistic regression model to compare the years of 2000, 2008 and 2013 to 1992. The results of this logistic regression analysis showed that students’ odds of choosing a match school for their first choice institution were significantly lower in 2008 and 2013 than in 1992. College matching for students who attended high schools serviced by the state initiative were compared using the percentage differences in college matching before and after the implementation of the program. However, results could not be interpreted with certainty due to the small size of the sample.

Compared to normal cells, cancer cells tend to have higher concentrations of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) due to an accelerated cellular metabolism. The high ROS content leaves cancer cells increasingly susceptible to oxidative stress-induced cell death. This susceptibility can be manipulated in selective cancer therapy by further increasing production of ROS or inhibiting peroxide removal systems or a combination of the two. Pharmacological ascorbate (high-dose intravenous ascorbate) has been shown to sensitize pancreatic cancer to ionizing radiation (IR) by increasing production of ROS such as H2O2. Glutathione reductase (GR) and thioredoxin reductase (TrxR) are both important enzymes in peroxide removal systems. GR and TrxR function to recycle key electron donors in the cellular removal of H2O2. We hypothesized that inhibiting the peroxide removal systems via inhibition of GR and TrxR would enhance ascorbate-induced cytotoxicity in pancreatic cancer cells. Inhibition of TrxR activity enhanced ascorbate-induced cytotoxicity in MIA PaCa-2 pancreatic cancer cells. Additionally, knockdown of GR protein expression in combination with pharmacological ascorbate treatment increased MIA PaCa-2 pancreatic cancer cell sensitivity to IR. In MIA PaCa-2 and 403 F1 patient-derived pancreatic cancer cells, inhibition of both TrxR and GR activity combined with pharmacological ascorbate enhanced radiosensitivity. However, this effect was not seen in 339 patient-derived pancreatic cancer cells treated with the same dose of ascorbate. In conclusion, inhibition of TrxR activity, GR activity, or both enhances radiosensitivity and ascorbate-induced cytotoxicity in some, but not all, pancreatic cancer cell lines. Treatments combining ascorbate with inhibition of H2O2 removal may be an effective strategy for treatment of pancreatic adenocarcinoma.

Reconstructed tomographic image resolution of small animal PET imaging systems is improving with advances in radiation detector development. However the trend towards higher resolution systems has come with an increase in price and system complexity. Recent developments in the area of solid-state photomultiplication devices like silicon photomultiplier arrays (SPMA) are creating opportunities for new high performance tools for PET scanner design. Imaging of excised small animal organs and tissues has been used as part of post-mortem studies in order to gain detailed, high-resolution anatomical information on sacrificed animals. However, this kind of ex-vivo specimen imaging has largely been limited to ultra-high resolution μCT. The inherent limitations to PET resolution have, to date, excluded PET imaging from these ex-vivo imaging studies. In this work, we leverage the diminishing physical size of current generation SPMA designs to create a very small, simple, and high-resolution prototype detector system targeting ex-vivo tomographic imaging of small animal organs and tissues. We investigate sensitivity, spatial resolution, and the reconstructed image quality of a prototype small animal PET scanner designed specifically for imaging of excised murine tissue and organs. We aim to demonstrate that a cost-effective silicon photomultiplier (SiPM) array based design with thin crystals (2 mm) to minimize depth of interaction errors might be able to achieve sub-millimeter resolution. We hypothesize that the substantial decrease in sensitivity associated with the thin crystals can be compensated for with increased solid angle detection, longer acquisitions, higher activity and wider acceptance energy windows (due to minimal scatter from excised organs). The constructed system has a functional field of view (FoV) of 40 mm diameter, which is adequate for most small animal specimen studies. We perform both analytical (3D-FBP) and iterative (ML-EM) methods in order to reconstruct tomographic images. Results demonstrate good agreement between the simulation and the prototype. Our detector system with pixelated crystals is able to separate small objects as close as 1.25 mm apart, whereas spatial resolution converges to the theoretical limit of 1.6 mm (half the size of the smallest detecting element), which is to comparable to the spatial resolution of the existing commercial small animal PET systems. Better system spatial resolution is achievable with new generation SiPM detector boards with 1 mm x 1 mm cell dimensions. We demonstrate through Monte Carlo simulations that it is possible to achieve sub-millimeter spatial image resolution (0.7 mm for our scanner) in complex objects using monolithic crystals and exploiting the light-sharing mechanism among the neighboring detector cells. Results also suggest that scanner (or object) rotation minimizes artifacts arising from poor angular sampling, which is even more significant in smaller PET designs as the gaps between the sensitive regions of the detector have a more exaggerated effect on the overall reconstructed image quality when the design is more compact. Sensitivity of the system, on the other hand, can be doubled by adding two additional detector heads resulting in a, fully closed, 4π geometry.