Matching Items (60)
Description
Filtration for microfluidic sample-collection devices is desirable for sample selection, concentration, preprocessing, and downstream manipulation, but microfabricating the required sub-micrometer filtration structure is an elaborate process. This thesis presents a simple method to fabricate polydimethylsiloxane (PDMS) devices with an integrated membrane filter that will sample, lyse, and extract the DNA from microorganisms in aqueous environments. An off-the-shelf membrane filter disc was embedded in a PDMS layer and sequentially bound with other PDMS channel layers. No leakage was observed during filtration. This device was validated by concentrating a large amount of cyanobacterium Synechocystis in simulated sample water with consistent performance across devices. After accumulating sufficient biomass on the filter, a sequential electrochemical lysing process was performed by applying 5VDC across the filter. This device was further evaluated by delivering several samples of differing concentrations of cyanobacterium Synechocystis then quantifying the DNA using real-time PCR. Lastly, an environmental sample was run through the device and the amount of photosynthetic microorganisms present in the water was determined. The major breakthroughs in this design are low energy demand, cheap materials, simple design, straightforward fabrication, and robust performance, together enabling wide-utility of similar chip-based devices for field-deployable operations in environmental micro-biotechnology.
ContributorsLecluse, Aurelie (Author) / Meldrum, Deirdre (Thesis advisor) / Chao, Joseph (Thesis advisor) / Westerhoff, Paul (Committee member) / Arizona State University (Publisher)
Created2011
Description
Hispanic youth have the highest risk for obesity, making this population a key priority for early childhood interventions to prevent the development of adult obesity and its consequences. Involving parents in these interventions is essential to support positive long-term physical activity and nutrition habits. Interventions in the past have engaged parents by providing information about nutrition and fruit and vegetable intake through written materials or text such as newsletters and text messages. The Sustainability via Active Garden Education (SAGE) intervention used gardening and interactive activities to teach preschool children ages 3-5 about healthy eating and physical activity. It aimed to increase physical activity and fruit and vegetable intake in preschool children as well as improve related parenting practices. The intervention utilized newsletters to engage parents by promoting opportunities to increase physical activity and fruit and vegetable intake for their children at home. The newsletters also encouraged parents to discuss what was learned during the SAGE lessons with their children. The purpose of this paper is to describe the content of the newsletters and determine the parent perception of the newsletters through parent survey responses. This can help inform future childhood obesity interventions and parent engagement.
ContributorsVi, Vinny (Author) / Lee, Rebecca (Thesis director) / Martinelli, Sarah (Committee member) / Edson College of Nursing and Health Innovation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Single cell phenotypic heterogeneity studies reveal more information about the pathogenesis process than conventional bulk methods. Furthermore, investigation of the individual cellular response mechanism during rapid environmental changes can only be achieved at single cell level. By enabling the study of cellular morphology, a single cell three-dimensional (3D) imaging system can be used to diagnose fatal diseases, such as cancer, at an early stage. One proven method, CellCT, accomplishes 3D imaging by rotating a single cell around a fixed axis. However, some existing cell rotating mechanisms require either intricate microfabrication, and some fail to provide a suitable environment for living cells. This thesis develops a microvorterx chamber that allows living cells to be rotated by hydrodynamic alone while facilitating imaging access. In this thesis work, 1) the new chamber design was developed through numerical simulation. Simulations revealed that in order to form a microvortex in the side chamber, the ratio of the chamber opening to the channel width must be smaller than one. After comparing different chamber designs, the trapezoidal side chamber was selected because it demonstrated controllable circulation and met the imaging requirements. Microvortex properties were not sensitive to the chambers with interface angles ranging from 0.32 to 0.64. A similar trend was observed when chamber heights were larger than chamber opening. 2) Micro-particle image velocimetry was used to characterize microvortices and validate simulation results. Agreement between experimentation and simulation confirmed that numerical simulation was an effective method for chamber design. 3) Finally, cell rotation experiments were performed in the trapezoidal side chamber. The experimental results demonstrated cell rotational rates ranging from 12 to 29 rpm for regular cells. With a volumetric flow rate of 0.5 µL/s, an irregular cell rotated at a mean rate of 97 ± 3 rpm. Rotational rates can be changed by altering inlet flow rates.
ContributorsZhang, Wenjie (Author) / Frakes, David (Thesis advisor) / Meldrum, Deirdre (Thesis advisor) / Chao, Shih-hui (Committee member) / Wang, Xiao (Committee member) / Arizona State University (Publisher)
Created2011
Description
Empirical and theoretical gaps exist on the subject matter of attendee experiential behavior at community festivals as this action occurs in real time. To acquire knowledge and begin to build theory, attendee behavior was investigated through an interpretive lens to give rise to a socially constructed understanding of this phenomenon in contrast to typical positivist inquiry designs found in the field of event studies used to test theory and determine universal explanations. This ontology was deemed appropriate as human experience at community festivals is multifaceted, relative to social interactions, highly variable with complex meanings, and has a wide variety of consequential implications; all views representative of social constructivism. A grounded theory approach was used in conjunction with a participant observation method to collect data on attendee behavior during fieldwork undertaken at community festivals. Prior to fieldwork, literature was not reviewed nor specific theory pre-selected to serve as a basis for research, with the researcher's only intent to record attendee's on-site actions with an open mind. Fieldwork notes were systematically expanded into descriptive narratives that were broken down into initial codes to establish robust analytic directions, which were synthesized into categories and subcategories through focused coding. Relationships between categories and subcategories were reassembled with axial coding bringing into view a strong emergent theme on social capital bonding and bridging at community festivals and a second theme that considers the aspirations of event management to program festive experiences. To strengthen the second theme event manager interviews and content analysis of event association newsletters were conducted as theoretical sampling to move data towards saturation. From emergent themes it was theorized, while social capital bonding is profusely exhibited at community festivals, social capital bridging is minimally displayed unless augmented with programmed festivity to increase physical, emotional, and social engagement of attendees. Literature reviewed in relation to this theory revealed that spirituality, dance, music, the arts, and wild abandonment were important elements of festivity. An implication arising from this study indicates that if community festivals consciously enhance programmed festivity then correspondingly increased social capital impacts within community development might also be achieved.
ContributorsBiaett, Vernon (Author) / Phillips, Rhonda (Thesis advisor) / Budruk, Megha (Committee member) / Hultsman, Wendy (Committee member) / De La Garza, Sarah (Committee member) / Arizona State University (Publisher)
Created2013
Description
Laboratory automation systems have seen a lot of technological advances in recent times. As a result, the software that is written for them are becoming increasingly sophisticated. Existing software architectures and standards are targeted to a wider domain of software development and need to be customized in order to use them for developing software for laboratory automation systems. This thesis proposes an architecture that is based on existing software architectural paradigms and is specifically tailored to developing software for a laboratory automation system. The architecture is based on fairly autonomous software components that can be distributed across multiple computers. The components in the architecture make use of asynchronous communication methodologies that are facilitated by passing messages between one another. The architecture can be used to develop software that is distributed, responsive and thread-safe. The thesis also proposes a framework that has been developed to implement the ideas proposed by the architecture. The framework is used to develop software that is scalable, distributed, responsive and thread-safe. The framework currently has components to control very commonly used laboratory automation devices such as mechanical stages, cameras, and also to do common laboratory automation functionalities such as imaging.
ContributorsKuppuswamy, Venkataramanan (Author) / Meldrum, Deirdre (Thesis advisor) / Collofello, James (Thesis advisor) / Sarjoughian, Hessam S. (Committee member) / Johnson, Roger (Committee member) / Arizona State University (Publisher)
Created2012
Description
Commitment to an activity is widely studied in leisure research. Serious Leisure Perspective (SLP) describes characteristics a committed activity participant possesses. The Psychological Continuum Model (PCM) describes the psychological process a person goes through to become committed to a leisure activity. Awareness, attraction, attachment and loyalty make of the four stages of PCM. Both perspectives have been used to describe committed leisure activity participants and commitment to organized recreational events. Research on leisure activity has yet to determine how the individual becomes loyal. Therefore, the purpose of this study is to determine the process in which recreation activity participates becomes loyal and to identify who can be labels as serious within the PCM Framework. Data was obtained from an online electronic survey distributed to participants of four U.S. marathon and half marathon events. A total of 579 responses were used in the final analysis. Path analysis determined the process in which a runner becomes committed. MANOVA is used to determine difference between leisure groups in the four stages of PCM. Results indicate that activity participants need to go through all four stages of PCM before becoming loyal. As knowledge increases, individuals are more motivated to participate. When the activity satisfies motives and becomes a reflection of their identity, feelings become stronger which results in loyalty. Socialization is instrumental to the progression through the PCM Framework. Additionally, attachment is the "bottleneck" in which all loyal activity participants my pass through. Differences exist between serious leisure groups in the attachment and loyalty stages. Those that are `less serious' are not as committed to the activity as their counterparts.
ContributorsMurphey, Elizabeth M (Author) / Lee, Woojin (Thesis advisor) / Hultsman, Wendy (Thesis advisor) / Larsen, Dale (Committee member) / Chisum, Jack (Committee member) / Arizona State University (Publisher)
Created2014
Description
The purpose of this study was to examine the local residents' perceptions toward the social impacts of FIBA EuroBasket 2011, held September 7th to September 12th, 2011 in Vilnius, Lithuania. This study focuses on the social impacts of the event since most of the mega-event academia is dominated by economic impact studies and this research attempts to go beyond a narrow quantitative approach to examine the social impacts in relation to two important academic contributions: 1) the embracement-withdrawal continuum and 2) the social exchange theory. A mixed methods analysis was adopted as the best approach for this research. Both a quantitative survey and qualitative questionnaire were used which yielded a total usable sample of 128 residents of Vilnius. Exploratory Factor Analysis was conducted to examine the underlying themes of the quantitative data and coding and thematic development was used to make sense of the qualitative data. The results confirmed that the event was considered successful (97% of residents embraced the event) and they generated 6 factors, or impacts, that were deemed important for influencing resident perceptions: social costs, social benefits, sociocultural impacts, socioeconomic impacts, sociopolitical impacts, and socioenvironmental impacts. These results indicate that the use of mixed methods analyses is crucial to investigate the interdependence between each impact that affects residents' perceptions toward sport mega-events.
ContributorsAntoniou, Alexis (Author) / Phillips, Rhonda (Thesis advisor) / Mean, Lindsey (Committee member) / Hultsman, Wendy (Committee member) / Arizona State University (Publisher)
Created2011
Description
Single cell analysis has become increasingly important in understanding disease onset, progression, treatment and prognosis, especially when applied to cancer where cellular responses are highly heterogeneous. Through the advent of single cell computerized tomography (Cell-CT), researchers and clinicians now have the ability to obtain high resolution three-dimensional (3D) reconstructions of single cells. Yet to date, no live-cell compatible version of the technology exists. In this thesis, a microfluidic chip with the ability to rotate live single cells in hydrodynamic microvortices about an axis parallel to the optical focal plane has been demonstrated. The chip utilizes a novel 3D microchamber design arranged beneath a main channel creating flow detachment into the chamber, producing recirculating flow conditions. Single cells are flowed through the main channel, held in the center of the microvortex by an optical trap, and rotated by the forces induced by the recirculating fluid flow. Computational fluid dynamics (CFD) was employed to optimize the geometry of the microchamber. Two methods for the fabrication of the 3D microchamber were devised: anisotropic etching of silicon and backside diffuser photolithography (BDPL). First, the optimization of the silicon etching conditions was demonstrated through design of experiment (DOE). In addition, a non-conventional method of soft-lithography was demonstrated which incorporates the use of two positive molds, one of the main channel and the other of the microchambers, compressed together during replication to produce a single ultra-thin (<200 µm) negative used for device assembly. Second, methods for using thick negative photoresists such as SU-8 with BDPL have been developed which include a new simple and effective method for promoting the adhesion of SU-8 to glass. An assembly method that bonds two individual ultra-thin (<100 µm) replications of the channel and the microfeatures has also been demonstrated. Finally, a pressure driven pumping system with nanoliter per minute flow rate regulation, sub-second response times, and < 3% flow variability has been designed and characterized. The fabrication and assembly of this device is inexpensive and utilizes simple variants of conventional microfluidic fabrication techniques, making it easily accessible to the single cell analysis community.
ContributorsMyers, Jakrey R (Author) / Meldrum, Deirdre (Thesis advisor) / Johnson, Roger (Committee member) / Frakes, David (Committee member) / Arizona State University (Publisher)
Created2012
Description
While I was brainstorming topics for my thesis project I came across the idea to look at weddings and specifically the wedding planning industry. It is an industry where very little research exists. It is important for the future of the industry to have some academic studies done on the wedding planning industry. When I started this project I was looking to find out about the characteristics of wedding satisfaction from a client perspective versus the planner's perspective and what deems a successful wedding planner. This could provide valuable insight while possibly shedding light on why some couples use a wedding planner and others do not. The research questions I will try to answer through the survey are: what are the characteristics of wedding satisfaction from a client perspective versus the planner's perspective and what deems a successful wedding planner from the client perspective versus the planner's perspective. I researched the industry and created a survey that was sent to a group of 15 planners. I hoped to get permission to send my survey to four to six previous clients from each planner. The list of wedding planners came from a board member of the International Special Events Society. If all surveys had been completed it would have given me a client pool of 60 to 80 couples. The problem was that none of the planners were willing to share the client survey with their clients. Therefore, I could not obtain a sufficient number of couples that had previously used wedding planners. I attempted to contact organizations that would have access to brides. I also attempted to reach out on Facebook and through email lists to married people who used wedding planners. None of these methods proved successful in amassing a sufficient number of individuals who used planners for their wedding. The project evolved into an analysis of the assistance options couples have to make big purchases like a wedding and a house. The amount spent on these big purchases varies as well as the time couples have to pay for them. There is also great variation in the kinds of resource's couples have to advise them before making these larger purchases. For example, when a couple is planning their wedding they can hire a wedding planner to assist them or do research on blogs and rely on parents and friends for help and assistance. When a couple prepares to buy a house (or another type of real estate) they will often hire a realtor. There are some resources online for the few couples that choose not to use a realtor, however, at some point they may need to seek a professional to assist with the legal documents. The inspiration behind this thesis was to begin academic research on a young industry where there was none. The profession of "wedding planning" is very new. There is no traditional academic research on the wedding planner as a profession. When the initial surveys and planners did not receive the kind of participation and cooperation needed it was disappointing that this project could not shed light on this young industry. The evolution of this project into a comparison between realtors and wedding planners suggested the potential of where the wedding planning as a profession could be was brought to light. If wedding planners and wedding planning as a profession could evolve to a place of necessity similar to purchasing a house the profession could gain validation and grow. At some point in that evolution, hopefully the profession would be in a better place for academic research and the individuals in the profession may be in a place to be more open to assist in that research. Ultimately getting to the place where a wedding planner is seen as necessary should be the goal for this profession. The amount of money spent, the emotional importance of the commitment and the legal promises involved in having a wedding creates that need but many people do not know this. Couples know very little about the individual costs that make up a wedding. A key problem with this is that it creates disconnect between couples expectations and budgets. If wedding planners could, through their marketing and other efforts, communicate with potential clients that a wedding planner is not a luxury, but a necessity, it would help insure emotional satisfaction and protect the financial investment of the couple and their family.
ContributorsMayberry, Sophia Elizabeth (Author) / Hultsman, Wendy (Thesis director) / Dempsey, Matt (Committee member) / Barrett, The Honors College (Contributor) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / School of Community Resources and Development (Contributor)
Created2015-05
Description
Over the span of little more than a decade, Phoenix Comicon has grown from its inception and unknown status to a nationally recognized event drawing 75,501 attendees in 2015. Using serious leisure and specialization theory, ethnographic research reveals the formation of individual identities and engagement methods with this sub-cultural phenomenon. In this case study research, seven interview participants provided in-depth accounts of their interests, experiences, and involvement with Phoenix Comicon. These reports demonstrate a high level of recognition with theory components, yielding a total 329 markers across all interview transcripts. The results match theory limitations, in that, participants may be engaged in serious leisure independent of length of involvement. However, long-term participation is linked to potential for deeper investment in a leisure activity and participants reporting greater personal fulfilment are associated with serious leisure principles such as: significant effort, occasional adversity, and durable benefits.
ContributorsScrogham, Nicholas Brandon (Author) / Hultsman, Wendy (Thesis director) / Shockley, Gordon (Committee member) / Squires, Jillian (Committee member) / School of Community Resources and Development (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05