Matching Items (213)
Description
The Phoenix-Metro area currently has problems with its transportation systems. Over-crowded and congested freeways have slowed travel times within the area. Express bus transportation and the existence of "High Occupancy" lanes have failed to solve the congestion problem. The light rail system is limited to those within a certain distance from the line, and even the light rail is either too slow or too infrequent for a commuter to utilize it effectively. To add to the issue, Phoenix is continuing to expand outward instead of increasing population density within the city, therefore increasing the time it takes to travel to downtown Phoenix, which is the center of economic activity. The people of Phoenix and its surrounding areas are finding that driving themselves to work is just as cost-effective and less time consuming than taking public transportation. Phoenix needs a cost-effective solution to work in co- existence with improvements in local public transportation that will allow citizens to travel to their destination in just as much time, or less time, than travelling by personal vehicle.
ContributorsSerfilippi, Jon (Author) / Ariaratnam, Samuel (Thesis director) / Pendyala, Ram (Committee member) / Pembroke, Jim (Committee member) / Barrett, The Honors College (Contributor) / Ira A. Fulton School of Engineering (Contributor)
Created2012-12
Description
Electrospun nanofibers can be prepared from various kinds of inorganic substances by electro-spinning techniques. They have great potential in many applications including super capacitors, lithium ion batteries, filtration, catalyst and enzyme carriers, and sensors [1]. The traditional way to produce electrospun nanofibers is needle based electro-spinning [1]. However, electrospun nanofibers have not been widely used in practice because of low nanofiber production rates. One way to largely increase the electro-spinning productivity is needleless electro-spinning. In 2005, Jirsak et al. patented a rotating roller fiber generator for the mass production of nanofibers [2]. Elmarco Corporation commercialized this technique to manufacture nanofiber equipment for the production of all sorts of organic and inorganic nanofibers, and named it "NanospiderTM". For this project, my goal is to build a needleless electro-spinner to produce nanofibers as the separator of lithium ion batteries. The model of this project is based on the design of rotating roller fiber generator, and is adapted from a project at North Dakota State University in 2011 [3].
ContributorsQiao, Guanhao (Author) / Yu, Hongyu (Thesis director) / Jiang, Hanqing (Committee member) / Goryll, Michael (Committee member) / Barrett, The Honors College (Contributor) / Ira A. Fulton School of Engineering (Contributor)
Created2012-12
Description
A new class of entrepreneurs is emerging in China, who are using a business model approach to solve societal problems. A small but growing niche of these so called "social entrepreneurs" is attempting to address long standing problems in the agricultural sector stemming from the three agricultural issues of farmers, agriculture and rural areas. In order to understand what social entrepreneurship means in the Chinese context, the motivations behind it, and the opportunities and problems related specifically to agricultural sector, interviews were conducted with social entrepreneurs, research institutes, and social fostering organizations in multiple tier-one cities in mainland China. Results show that the concept of social enterprise is comprehended in a very different way in the Chinese context relative to the general usage of the term in the literature. Social enterprises in the agricultural sector are divided into categories of Community Supported Agriculture-based organic farms, farmers' markets, food educators and city farmers. This is a growing group of entrepreneurs who could be better supported on the basis of resources and protection by the government, law and policy, universities, and a united producer and consumer front.
ContributorsGray, Christopher Stephan (Author) / Aggarwal, Rimjhim (Thesis director) / Ostrom, Amy (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Department of Marketing (Contributor)
Created2013-12
Description
Protein AMPylation is a recently discovered and relatively unstudied post-translational modification (PTM). AMPylation has previously been shown to play an important role in metabolic regulation and host pathogenesis in bacteria, but the recent identification of potential AMPylators across many species in every domain of life has supported the possibility that AMPylation could be a more fundamental and physiologically significant regulatory PTM. For the first time, we characterized the auto-AMPylation capability of the human protein SOS1 through in vitro AMPylation experiments using full-length protein and whole-domain truncation mutants. We found that SOS1 can become AMPylated at a tyrosine residue possibly within the Cdc25 domain of the protein, the Dbl homology domain is vital for efficient auto-AMPylation activity, and the C-terminal proline-rich domain exhibits a complex regulatory function. The proline-rich domain alone also appears to be capable of catalyzing a separate, unidentified covalent self-modification using a fluorescent ATP analogue. Finally, SOS1 was shown to be capable of catalyzing the AMPylation of two endogenous human protein substrates: a ubiquitous, unidentified protein of ~49kDa and another breast-cancer specific, unidentified protein of ~28kDa.
ContributorsOber-Reynolds, Benjamin John (Author) / LaBaer, Joshua (Thesis director) / Borges, Chad (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
In this thesis, glycan nodes, the basic subunits of complex biological sugars, were studied to determine the reproducibility of gas chromatography-mass spectrometry (GC/MS) based methylation analysis of whole blood plasma by normalization using an internal standard of heavy permethylated glycans. Glycans are complex biological sugars that have a variety of applications in the human body and will display aberrant compositions when produced by cancerous cells. Thus an assay to determine their composition can be used as a diagnostic tool. It was shown that the assay may have potential use, but needs further refinement to become an improvement over current methods by analyzing the results of ratio-determination and replicate experiments.
ContributorsMiyasaki, Tyler Takeo (Author) / Borges, Chad (Thesis director) / Van Horn, Wade (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
Description
Western diets, high in dietary fat and red meat, are associated with hyperglycemia and weight gain, symptoms that promote insulin resistance and diabetes. Previous studies have shown that elevated glucose promotes glycation of circulating proteins such as albumin, which is thought to lead to hyperglycemia complications. It was hypothesized that diets with no meat consumption (pesco-vegetarian and lacto-vegetarian) would reduce protein glycation, in comparison to a diet with meat. Forty six healthy adult omnivorous subjects were randomized into one of three groups and instructed to either consume red meat (i.e. meat) or poultry twice per day (control), eliminate meat and increase fish consumption (pesco-vegetarian), or adopt a vegetarian diet devoid of fish, meat or poultry (lacto-vegetarian) for four weeks. Fasting plasma samples were collected from participants at baseline and after 4 weeks of the dietary intervention. Plasma glucose concentrations were measured using a commercially available kit. Percent glycated albumin was measured on a separate aliquot of plasma by mass spectrometry. Plasma glucose concentrations were significantly increased following 4-weeks of pesco-vegetarian diet (P=0.002, paired t-test). Neither the lacto-vegetarian (P=0.898) or the control diet (P=0.233) affected plasma glucose concentrations. Despite the significant increase in plasma glucose following a pesco-vegetarian diet, no change in percent glycated albumin was observed (P>0.50, ANOVA). These findings may indicate a protective effect of the pesco-vegetarian diet on protein glycation in the presence of elevated plasma glucose and suggest the need for additional studies to examine the link between increased fish consumption and glucose regulation.
ContributorsRaad, Noor (Author) / Sweazea, Karen (Thesis director, Committee member) / Borges, Chad (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Great disasters can often serve as birthing grounds for national transformation. As communities work to recover and rebuild, opportunities to reassess of prevailing development theories and programs may arise. As traditional development programs, supported by top-down development theories and billions in foreign aid, have not changed Haiti's impoverished status, such an opportunity has been presented to the Caribbean nation. Just a few months removed from the devastating 7.0 earthquake of Jan 12, 2010, this study identified the emergent thinking about development as expressed by key informants (N=21) from six entity types involved in Haiti's rebuilding efforts - government agencies, social ventures, grassroots, diaspora, foreign, and hybrid nonprofits. Findings were supplemented by participant observation of a civil society meeting in Port-au-Prince, Haiti. The Sustainable Livelihoods (SL) Framework was used as a lens with which to understand the causes of Haiti's social, institutional, environmental, and economic vulnerabilities. Modified grounded theory was used as the qualitative data analytical method from which five themes emerged: Haitian government, rebuilding, aid work and its effects, Haitian society, and international interference. Participants called for a refoundation, the building a nation from the ground up, of Haiti. Based on these findings, four transformative processes were identified as fundamental to Haiti's refoundation: 1) communication and collaboration with the Haitian government, 2) engagement of the Haitian people and the Haitian diaspora in the redevelopment work, 3) a broad vision of development for the nation, and 4) coordination and collaboration among NGOs.
ContributorsInnocent, Darlye Élise (Author) / Knopf, Richard (Thesis advisor) / Phillips, Rhonda (Committee member) / Aggarwal, Rimjhim (Committee member) / Wang, Lili (Committee member) / Arizona State University (Publisher)
Created2010
Description
Environmental change and natural hazards represent a challenge for sustainable development. By disrupting livelihoods and causing billions of dollars in damages, disasters can undo many decades of development. Development, on the other hand, can actually increase vulnerability to disasters by depleting environmental resources and marginalizing the poorest. Big disasters and big cities get the most attention from the media and academia. The vulnerabilities and capabilities of small cities have not been explored adequately in academic research, and while some cities in developed countries have begun to initiate mitigation and adaptation responses to environmental change, most cities in developing countries have not. In this thesis I explore the vulnerability to flooding of the US-Mexico border by using the cities of Nogales, Arizona, USA and Nogales, Sonora, Mexico as a case study. I ask the following questions: What is the spatial distribution of vulnerability, and what is the role of the border in increasing or decreasing vulnerability? What kind of coordination should occur among local institutions to address flooding in the cities? I use a Geographic Information System to analyze the spatial distribution of flood events and the socio-economic characteristics of both cities. The result is an index that estimates flood vulnerability using a set of indicators that are comparable between cities on both sides of the border. I interviewed planners and local government officials to validate the vulnerability model and to assess collaboration efforts between the cities. This research contributes to our understanding of vulnerability and sustainability in two ways: (1) it provides a framework for assessing and comparing vulnerabilities at the city level between nations, overcoming issues of data incompatibility, and (2) it highlights the institutional arrangements of border cities and how they affect vulnerability.
ContributorsMárquez Reyes, Bernardo J (Author) / Eakin, Hallie (Thesis advisor) / Lara-Valencia, Francisco (Thesis advisor) / Aggarwal, Rimjhim (Committee member) / Arizona State University (Publisher)
Created2010
Description
Dielectrophoresis is a separations strategy that has the potential to separate small amounts of different proteins from each other. The forces at play in the channel used for dielectrophoresis are electroosmotic flow (EOF), electrophoresis (EP), and dielectrophoresis (DEP). EOF is the force exerted on liquid from an applied potential (1). EP is the force exerted on charged particles in a uniform electric field (2). DEP is the force exerted on particles (charged and uncharged) in a non-uniform electric field (3). This experiment was focused on the testing of a new microfluidic device to see if it could improve the focusing of proteins in dielectrophoresis. It was predicted that the addition of a salt bridge would improve focusing by preventing the ions created by the electrolysis of water around the electrodes from interacting with the proteins and causing aggregation, among other problems. Control trials using the old device showed that electrolysis was likely occurring and was the causal agent for poor outcomes. After applying the electric potential for some time a pH front traveled through the channel causing aggregation of proteins and the current in the channel decreased rapidly, even while the voltage was held constant. The resistance in the channels of the control trials also slightly decreased over time, until the pH shift occurred, at which time it increased rapidly. Experimental trials with a new device that included salt bridges eliminated this pH front and had a roughly linear increase of current in the channel with the voltage applied. This device can now be used in future research with protein dielectrophoresis, including in the potential differentiation of different proteins. References: 1) Electroosmosis. Oxford Dictionary of Biochemistry and Molecular Biology. 2. Oxford University Press: Oxford, England. 2006. 2) Electrophoresis. Oxford Dictionary of Biochemistry and Molecular Biology. 2. Oxford University Press: Oxford, England. 2006. 3) Dielectrophoresis. Oxford Dictionary of Biochemistry and Molecular Biology. 2. Oxford University Press: Oxford, England. 2006.
ContributorsHayes, Katelyn Donna (Author) / Hayes, Mark (Thesis director) / Borges, Chad (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Mathematical epidemiology, one of the oldest and richest areas in mathematical biology, has significantly enhanced our understanding of how pathogens emerge, evolve, and spread. Classical epidemiological models, the standard for predicting and managing the spread of infectious disease, assume that contacts between susceptible and infectious individuals depend on their relative frequency in the population. The behavioral factors that underpin contact rates are not generally addressed. There is, however, an emerging a class of models that addresses the feedbacks between infectious disease dynamics and the behavioral decisions driving host contact. Referred to as “economic epidemiology” or “epidemiological economics,” the approach explores the determinants of decisions about the number and type of contacts made by individuals, using insights and methods from economics. We show how the approach has the potential both to improve predictions of the course of infectious disease, and to support development of novel approaches to infectious disease management.
ContributorsPerrings, Charles (Author) / Castillo-Chavez, Carlos (Author) / Chowell-Puente, Gerardo (Author) / Daszak, Peter (Author) / Fenichel, Eli P. (Author) / Finnoff, David (Author) / Horan, Richard D. (Author) / Kilpatrick, A. Marm (Author) / Kinzig, Ann (Author) / Kuminoff, Nicolai (Author) / Levin, Simon (Author) / Morin, Benjamin (Author) / Smith, Katherine F. (Author) / Springborn, Michael (Author) / Simon M. Levin Mathematical, Computational and Modeling Sciences Center (Contributor) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / W.P. Carey School of Business (Contributor) / Economics (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor)
Created2015-12-01