• Modeling of nucleation rate of supersaturated calcium sulfate solutions

      Jonathas, David; Department of Chemical and Environmental Engineering (2012-11-09)
    • Modeling the Effect of Shocks and Stresses on the Reliability of Networks with Radial Topologies

      Mangal, Kunal; Larsen, Alexandra; Chryst, Breanne; Rojo, Javier; University of Arizona; Centenary College; University of Utah; Rice University (2011-11-04)
      We consider the impact that various shocks and stresses have on the reliability of networks with radial topology, such as an electrical power grid. We incorporate the effects of aging, geographical risk, and local dependence between components into a model of overall system reliability. We also simulate how the system fares under extreme weather events, such as hurricanes. Our model gives a flexible and general understanding of how outside forces affect network reliability and can be adapted to a range of specific uses. We run a simulation using this model which yields realistic results.
    • More than a Classroom: Learners Voices - How should Iskashitaa use our ESL Classes as a Space to Increase Self-Sufficiency, Language Acquisition and as a Bridge to the Community for our Adult Refugee Students?

      Zaleski, Kathryn N.; Language, Reading and Culture; Department of Teaching, Learning and Sociocultural Studies (2011-11-04)
      What are Iskashitaa Refugee Harvesting Network’s roles and objectives in teaching English as a Second Language to adult refugees in the Tucson community? How can we create a classroom environment that builds their language acquisition while promoting self-sufficiency? To inquire into these questions, interviews were conducted with adult refugee students who attend the classes, anecdotal records were kept of the ESL teachers’ weekly reflections and classroom observations were performed. Iskashitaa’s ESL classes should provide a space for English language acquisition, assisting in the acculturation process through introducing material that is based on life-skills, with the teachers serving as a cultural broker, advocate and friend and finally, introducing the adult refugees to the community through volunteer activities with Iskashitaa. There is a need for more inquiry and discussion about the pre-literate refugee population, especially in effective teaching strategies, curriculum ideas and a better understanding of literacy practices within the home. These are matters that merit a larger discussion by people who work in education and with refugees, as feedback would be beneficial from all who work with refugees and can recommend what they have observed, experienced and envision to help in the language acquisition, self-sufficiency and acculturation process for refugees.
    • Morphological examination of the relationship between astrocyte-like glia and neuronal synapses in Drosophila

      Liu, Kendra; MacNamee, Sarah; Gerhard, Stephen; Fetter, Richard; Cardona, Albert; Tolbert, Leslie; Oland, Lynne; University of Arizona Department of Neuroscience; Undergraduate Program in Neuroscience and Cognitive Science; HHMI Janelia Research Campus; et al. (2016-02-24)
      The nervous system is composed of two types of cells: neurons and glia. In neuronal circuits, neurons communicate through synapses and glia play a crucial modulatory role. To modulate chemical reuptake, glia send processes close to synapses and many glia directly appose or ensheathe a synapse. This structural motif is one of the elements often included in describing a vertebrate tripartite synapse, which includes a bidirectional functional neuron-glia relationship. The exact nature of this neuron-glia communication is not well understood. In the invertebrate fruit fly, we have also found that particular neurons and glia also have a bidirectional functional relationship. This allows us to ask new questions about glial morphology. Throughout multiple images, I identified particular neuronal synapses and surrounding glia. After creating a 3D reconstruction, I measured the distance between a particular neuronal synapse and its closest glial process. Interestingly, the neuronal synapses were not directly apposed or ensheathed by glia, and the distance to the closest glial process varied one-hundred-fold. With variable distance, functional communication is consistently present. These findings provide important insight into invertebrate neuron-glia communication, and offer new avenues to investigate the structural neuron-glia relationships that are required for reciprocal signaling between the two cell classes.
    • Navigating Love and Money: Lessons from Ukraine

      Anderson, Nadina; Department of Sociology (2016-02-24)
    • Non-parents recover faster than parents following divorce

      Rojo-Wissar, Darlynn M.; Dawson, Spencer C.; Davidson, Ryan D.; Sbarra, David A.; Beck, Connie J.A.; Mehl, Matthias R.; Bootzin, Richard R.; Department of Psychology, University of Arizona (2013-11-08)
    • Noninvasive Genetics - A Powerful Tool for Wildlife Management

      Naidu, Ashwin; Smythe, Lindsay; Thompson, Ron; Culver, Melanie; School of Natural Resources and the Environment, University of Arizona; U.S. Fish and Wildlife Service - Kofa National Wildlife Refuge, Yuma, Arizona; Borderlands Research Institute, Sul Ross State University, Alpine, Texas; U.S. Geological Survey - Arizona Co-operative Fish and Wildlife Research Unit, Tucson, Arizona (2012-11-09)
    • Notch house Design Build Collaboration Project: House VII

      Durrett, Tasanee; College of Architecture, Planning, and Landscape Architecture (2016-02-24)
      Architecture has the power to create an inclusive society where everyone feels as if they have a voice and responsibility to a sustainable future. With collaboration and dedication, architectural design can have a huge impact on the living conditions of underrepresented communities. Working through the Drachman Design Build Coalition, the scope of the project involves designing and constructing an affordable dwelling for a low-income family in the city of Tucson, Arizona. The overall mission of building affordable housing is to provide under-served families with housing opportunities that would not be otherwise. The house will be designed as a 2-3 bedroom dwelling with 2 bathrooms, and indoor living space, outdoor living area, and a carport. Through research and physical observation, potential sites were explored, sustainable strategies were learned, and affordable housing techniques were studied. Many iterations of housing models were developed based on information gained from local books and journals written on traditional southwestern housing designs. The Notch House starts to develop as a sustainable affordable housing project designed in response to underrepresented families in Tucson.
    • A novel strategy to attenuate the inhibitory effects of nitrite on the anaerobic ammonium oxidation (anammox) process

      Li, Guangbin; Vilcherrez, David; Carvajal-Arroyo, Jose Maria; Puyol, D.; Sierra-Alvarez, Reyes; Field, Jim A.; Department of Chemical & Environmental Engineering (2014-11-07)
    • Passivation of III-V Semiconductor Surfaces

      Contreras, Yissel; Muscat, Anthony; Department of Chemical and Environmental Engineering, University of Arizona; Department of Chemical and Environmental Engineering, University of Arizona (2013-11-08)
      Computer processor chips of the last generation are based on silicon, modified to achieve maximum charge mobility to enable fast switching speeds at low power. III-V semiconductors have charge mobilities that are much higher than that of silicon making them suitable candidates for boosting the performance of new electronic devices. However, III-V semiconductors oxidize rapidly in air after oxide etching and the poor quality of the resulting oxide limits device performance. Our goal is to design a liquid-phase process flow to etch the oxide and passivate the surface of III-V semiconductors and to understand the mechanism of layer formation.Self-assembled monolayers of 1-eicosanethiol (ET) dissolved in ethanol, IPA, chloroform, and toluene were deposited on clean InSb(100) surfaces. The InSb passivated surfaces were characterized after 0 to 60 min of exposure to air. Ellipsometry measurements showed a starting overlayer thickness (due to ET, oxides, or both) of about 20 Å in chloroform and from 32 to 35 Å in alcohols and toluene. Surface composition analysis of InSb with X-ray photoelectron spectroscopy after passivation with 0.1 mM ET in ethanol confirmed the presence of ET and showed that oxygen in the Auger region is below detection limits up to 3 min after the passivation. Our results show that a thiol layer on top of a non-oxidized or low-oxide semiconductor surface slows oxygen diffusion in comparison to a surface with no thiol present, making this a promising passivation method of III-V semiconductors.
    • Plant fiber reinforced geopolymer - A green and high performance cementitious material

      Chen, Rui; Ahmari, Saeed; Gregory, Mark; Zhang, Lianyang; Department of Civil Engineering and Engineering Mechanics (2011-11-04)
    • Pollen Foraging Bees Don't Learn Unsaturated Floral Color

      Newman, China Rae; Papaj, Dan; Russell, Avery; Ecology and Evolutionary Biology; Entomology and Insect Science (2016-02-24)
      We investigated whether bees have an innate preference for flowers with saturated pigments and whether experience altered any preference. Preference could be a result of reward quality varying by color morph and/or responses to the petals, anthers, or their combination. Consequently, we gave bees experience on one of four floral configurations created from two color morphs of Solanum tridynanum. We subsequently tested learned preference using an array of all four configurations. Changes in preference as a result of experience were not mediated by anthers, only by petals. Bees that first experienced configurations with purple petals subsequently preferred configurations with purple petals, relative to naïve bees. However, bees that first experienced white petals showed no subsequent change in preference relative to naïve bees. Surprisingly, naïve bees showed no preference for any particular floral configuration. Rather than an innate preference for flowers with more saturated colors, bees are less able to develop a preference for unsaturated types. Because individuals are more able to develop a preference for saturated flowers, these flowers experience greater visitation, and thus greater pollination success, over unsaturated types.
    • PVMirror – A High-Efficiency Solar Module

      Hyatt, Justin; Mrkonich, Jeffrey; Reinhart, Lennon; Taylor, Wyatt; Steward Observatory; College of Optical Sciences; Department of Aerospace and Mechanical Engineering (2016-02-24)
      To make photovoltaics (PV) and concentrated solar thermal power (CSP) more practical forms of alternative energy, creative innovations to current solar energy methods must be employed. The PVMirror – a new technology – is our solution to that problem. The PVMirror combines PV and CSP technologies by splitting the spectrum of sunlight using a dichroic mirror film. Light that is not transmitted to the solar cell is to instead be reflected to a focus, by way of a curved mirror. This hybrid of technologies is competitive, as it is both efficient and affordable compared to many other innovations in renewable energy. The PVMirror is designed to be an easy and cost-effective replacement to the reflectors used in existing CSP plants. Ultimately, we hope to demonstrate this PVMirror technology on a large scale and market it. As validated from interviewing with industry professionals, this technology has the potential to impact the world of solar energy because many industrial companies and utility-scale CSP project developers are interested in pairing CSP and PV to increase efficiency. Currently, using an outdoor sun tracker, we are testing an 18 inch by 18 inch prototype with four solar cells.
    • Queer-Ability: History, Culture, and the Future of the Intersection of LGBTQ and Disability Studies

      Przybylowicz, Stephan Elizander; School of Information Resources & Library Science; Sonoran UCEDD Interdisciplinary Training Program (2011-11-04)
    • Renegotiating the Interface Between the Built and Natural Environments

      Johnson, Nicholas (2011-11-04)
      As human consumption and energy production continue to negatively a ect our environment, a re-conceptualization of our relationship to the wider world becomes a necessary step in the coexistence of humankind and nature. Modern methods of building have sought to establish a universal conception of human comfort that is disconnected from the realities of the speci c and varied climates in which we live. The building envelope is seen as a barrier to nature, a fortress where we have complete control over the parameters of our environment. This degree of control ultimately requires an unlimited source of energy. Through development of emerging material systems and technological integration, this project seeks to create a dialog between interior and exterior environments, recognizing that the two should be connected. This re-envisioned interface responds directly to changing environmental conditions through formal and material adaptations which create a symbiotic relationship between the built and natural worlds
    • Stage of invasion: How do sensitive seedlings respond to buffelgrass?

      Sommers, Pacifica; Ecology and Evolutionary Biology (2011-11-04)
    • Theoretics Into Practice: Dance Documentation and Preservation

      Sheather, Danielle; School of Dance, University of Arizona (2014-11-07)
    • Una revolución escrita: The Mexican-American Anthology

      Collins, Hannah; Department of Spanish & Portuguese, University of Arizona (2014-11-07)