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- Creators: Arizona State University
Description
Titanium dioxide (TiO2) nanomaterial use is becoming more prevalent as is the likelihood of human exposure and environmental release. The goal of this thesis is to develop analytical techniques to quantify the level of TiO2 in complex matrices to support environmental, health, and safety research of TiO2 nanomaterials. A pharmacokinetic model showed that the inhalation of TiO2 nanomaterials caused the highest amount to be absorbed and distributed throughout the body. Smaller nanomaterials (< 5nm) accumulated in the kidneys before clearance. Nanoparticles of 25 nm diameter accumulated in the liver and spleen and were cleared from the body slower than smaller nanomaterials. A digestion method using nitric acid, hydrofluoric acid, and hydrogen peroxide was found to digest organic materials and TiO2 with a recovery of >80%. The samples were measured by inductively coupled plasma-mass spectrometry (ICP-MS) and the method detection limit was 600 ng of Ti. An intratracheal instillation study of TiO2 nanomaterials in rats found anatase TiO2 nanoparticles in the caudal lung lobe of rats 1 day post instillation at a concentration of 1.2 ug/mg dry tissue, the highest deposition rate of any TiO2 nanomaterial. For all TiO2 nanomaterial morphologies the concentrations in the caudal lobes were significantly higher than those in the cranial lobes. In a study of TiO2 concentration in food products, white colored foods or foods with a hard outer shell had higher concentrations of TiO2. Hostess Powdered Donettes were found to have the highest Ti mass per serving with 200 mg Ti. As much as 3.8% of the total TiO2 mass was able to pass through a 0.45 um indicating that some of the TiO2 is likely nanosized. In a study of TiO2 concentrations in personal care products and paints, the concentration of TiO2 was as high as 117 ug/mg in Benjamin Moore white paint and 70 ug/mg in a Neutrogena sunscreen. Greater than 6% of Ti in one sunscreen was able to pass through a 0.45 um filter. The nanosized TiO2 in food products and personal care products may release as much as 16 mg of nanosized TiO2 per individual per day to wastewater.
ContributorsWeir, Alex Alan (Author) / Westerhoff, Paul K (Thesis advisor) / Hristovski, Kiril (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2011
Description
Since its launch by the US Green Building Council (USGBC), Leadership in Energy and Environmental Design (LEED) certification has been postured as the "gold standard" for environmentally conscious, sustainable building design, construction and operations. However, as a "living measurement", one which requires ongoing evaluation and reporting of attainment and compliance with LEED certification requirements, there is none. Once awarded, LEED certification does not have a required reporting component to effectively track continued adherence to LEED standards. In addition, there is no expiry tied to the certification; once obtained, a LEED certification rating is presumed to be a valid representation of project certification status. Therefore, LEED lacks a requirement to demonstrate environmental impact of construction materials and building systems over the entire life of the project. Consequently, LEED certification is merely a label rather than a true representation of ongoing adherence to program performance requirements over time. Without continued monitoring and reporting of building design and construction features, and in the absence of recertification requirements, LEED is, in reality, a gold star rather than a gold standard. This thesis examines the lack of required ongoing monitoring, reporting, or recertification requirements following the award by the USGBC of LEED certification; compares LEED with other international programs which do have ongoing reporting or recertification requirements; demonstrates the need and benefit of ongoing reporting or recertification requirements; and explores possible methods for implementation of mandatory reporting requirements within the program.
ContributorsCarpenter, Anne Therese (Author) / Olson, Larry (Thesis advisor) / Hild, Nicholas (Committee member) / Brown, Albert (Committee member) / Arizona State University (Publisher)
Created2013
Description
From the instructional perspective, the scope of "active learning" in the literature is very broad and includes all sorts of classroom activities that engage students with the learning experience. However, classifying all classroom activities as a mode of "active learning" simply ignores the unique cognitive processes associated with the type of activity. The lack of an extensive framework and taxonomy regarding the relative effectiveness of these "active" activities makes it difficult to compare and contrast the value of conditions in different studies in terms of student learning. Recently, Chi (2009) proposed a framework of differentiated overt learning activities (DOLA) as active, constructive, and interactive based on their underlying cognitive principles and their effectiveness on students' learning outcomes. The motivating question behind this framework is whether some types of engagement affect learning outcomes more than the others. This work evaluated the effectiveness and applicability of the DOLA framework to learning activities for STEM classes. After classification of overt learning activities as being active, constructive or interactive, I then tested the ICAP hypothesis, which states that student learning is more effective in interactive activities than constructive activities, which are more effective than active activities, which are more effective than passive activities. I conducted two studies (Study 1 and Study 2) to determine how and to what degree differentiated activities affected students' learning outcomes. For both studies, I measured students' knowledge of materials science and engineering concepts. Results for Study 1 showed that students scored higher on all post-class quiz questions after participating in interactive and constructive activities than after the active activities. However, student scores on more difficult, inference questions suggested that interactive activities provided significantly deeper learning than either constructive or active activities. Results for Study 2 showed that students' learning, in terms of gain scores, increased systematically from passive to active to constructive to interactive, as predicted by ICAP. All the increases, from condition to condition, were significant. Verbal analysis of the students' dialogue in interactive condition indicated a strong correlation between the co-construction of knowledge and learning gains. When the statements and responses of each student build upon those of the other, both students benefit from the collaboration. Also, the linear combination of discourse moves was significantly related to the adjusted gain scores with a very high correlation coefficient. Specifically, the elaborate type discourse moves were positively correlated with learning outcomes; whereas the accept type moves were negatively correlated with learning outcomes. Analyses of authentic activities in a STEM classroom showed that they fit within the taxonomy of the DOLA framework. The results of the two studies provided evidence to support the predictions of the ICAP hypothesis.
ContributorsMenekşe, Muhsin (Author) / Chi, Michelene T.H. (Thesis advisor) / Baker, Dale (Committee member) / Middleton, James (Committee member) / Arizona State University (Publisher)
Created2012
Description
The handling of waste encompasses the following processes: recycling, collection, treatment, and disposal. It is crucial to provide a cost-effective waste management system that improves public health and reduces environmental risks. In developing countries, proper handling of solid and hazardous wastes remain severely limited in urban cities if the industries and hospitals producing it do not take responsibility. Recycling and reusing of 12% of total waste in Phnom Penh is an active industry in Cambodia, driven by an informal network of waste pickers, collectors, and buyers. This thesis examines the environmental situation of solid and hazardous wastes in Phnom Penh. The socio-economic background of waste pickers and their current practices for handling solid and hazardous wastes will be mainly discussed in order to understand health and sanitation impacts and risks for disposal of solid and hazardous waste by these informal waste pickers. Surveys and interviews with the following sources are conducted: waste pickers, community members, observation at local dumpsites, governmental officials, and other non-government organization agencies in Phnom Penh, Cambodia. This thesis reports the external and internal factors that hinder safety and cost-effective management for disposal of solid and hazardous wastes. Multiple literature reviews are assessed in regards to the health effects, economic, and social impacts in developing countries. Evidentially, after attending several training and environmental awareness-raising programs, waste pickers expressed concerns about their health and the environment. Instead of receiving support, waste pickers are under economic pressure to use improper tools for waste picking, to stop working, get access to health care/service, to change their career, and prevent contact to limit serious communicable diseases and disability. As a result, the government and other related government agencies have made an effort to establish sanitation handling, treatment, and disposal systems by closing the old dumpsite. Due to limited entrepreneurship and business experience after training, most waste pickers cannot initiate micro business or find new jobs and then resume their waste picking. In conclusion, this thesis proposed that there are alternative technologies and management methods that will allow waste pickers to maintain employment while minimizing hazardous waste. Some examples of alternatives for waste pickers are establishing a material recovery center and alternative higher income occupation.
ContributorsChhun, Gina (Author) / Parmentier, Mary (Thesis advisor) / Grossman, Gary (Committee member) / Maneepong, Chuthatip (Committee member) / Arizona State University (Publisher)
Created2012
Description
In the United States, some 94 million people (29% of the US population) live in areas immediately adjacent to a coast. The global phenomenon of climate-induced environmental change is largely framed as a one-way cause-and-effect relationship, where individuals, communities, and populations inhabiting at-risk locations are either forced to relocate or do so of their own accord. Yet residents of such at-risk areas are increasingly actively choosing to remain, even as risk intensifies. Using a mixed-methods approach, this dissertation examines environmental perceptions, the internalization of risk, the influence of information sources, and how individuals residing in coastal locations process their migration decisions. Established migration and hazard frameworks and theory are poorly positioned to understand the environments’ role in migration decisions. From these perspectives, environmental factors are near exclusively framed as negative affective biophysical push factors. Migration frameworks also fail to adequately incorporate reasons for non-migration. This dissertation directly addresses both these gaps in understanding. This research utilizes data from across the Gulf Coast, with a focus on fieldwork from Terrebonne Parish, Louisiana, and a dataset of 123 surveys and 63 interviews across a diverse group of coastal residents. Residents perceive of their environment in much more robust terms than just the biophysical. A majority of terms incorporated social and cultural aspects of environment, and environmental meaning was expressed across a continuum of proximal (most important/close) to more distal (less important/distant) scales. Little support is found for the traditional idea that economic or natural-environmental factors are more influential in decisions to migrate away from ones’ home. In predicting migration intention, socially and environmentally derived variables improved migration model performance. This dissertation demonstrates that internalization of risk by coastal residents is not a straightforward relationship, but rather one mediated by; social-environmental factors, personal experience, sense of place, and trust, which in turn influences intention to migrate, move locally, or remain in place. Residents perceive of their environment far more broadly than current risk-management planning allows. Results provide coastal residents, as well as community leaders and emergency managers who perceive environment differently, new tools for productive engagement and future policy development within coastal landscapes.
ContributorsTill, Charlotte Emma (Author) / BurnSilver, Shauna (Thesis advisor) / Tsuda, Takeyuki (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created2022
Description
Urea is an added value chemical with wide applications in the industry and agriculture. The release of urea waste to the environment affects ecosystem health despite its low toxicity. Online monitoring of urea for industrial applications and environmental health is an unaddressed challenge. Electroanalytical techniques can be a smart integrated solution for online monitoring if sensors can overcome the major barrier associated with long-term stability. Mixed metal oxides have shown excellent stability in environmental conditions with long lasting operational lives. However, these materials have been barely explored for sensing applications. This work presents a proof of concept that demonstrates the applicability of an indirect electroanalytical quantification method of urea. The use of Ti/RuO2-TiO2-SnO2 dimensional stable anode (DSA®) can provide accurate and sensitive quantification of urea in aqueous samples exploiting the excellent catalytic properties of DSA® on the electrogeneration of active chlorine species. The cathodic reduction of accumulated HClO/ClO− from anodic electrogeneration presented a direct relationship with urea concentration. This novel method can allow urea quantification with a competitive LOD of 1.83 × 10−6 mol L−1 within a linear range of 6.66 × 10−6 to 3.33 × 10−4 mol L−1 of urea concentration.
ContributorsVasconcellos, Maria de Lourdes S. (Author) / Silva, Luiz Ricardo G. (Author) / Lee, Chung-Seop (Author) / Fajardo, Ana Sofia dos Santos (Author) / Garcia-Segura, Sergi (Author) / Ribeiro, Josimar (Author)
Created2021-05-15
Description
An Earned Value Management System (EVMS) is an organization’s system for project/program management that integrates a defined set of associated work scopes, schedules and budgets, allowing for effective planning, performance, and management control. A mature EVMS that is compliant with standards and guidelines, and that is applied in a positive social environment is critical to the overall success of large and complex projects and programs. However, a comprehensive and up-to-date literature review revealed a lack of a data-driven and consistent rating system that can gauge the maturity and the environment surrounding EVMS implementation. Therefore, the primary objective of this dissertation focuses on the EVMS maturity and environment, and investigates their impact on project performance. The author was one of the 41 research team members whose goal was to develop the novel rating system called Integrated Project/Program Management (IP2M) Maturity and Environment Total Risk Rating (METRR). Using a multi-method research approach, the rating system was developed based on a literature review of more than 600 references, a survey with 294 responses, focus group meetings, and research charrettes with more than 100 subject matter experts from the industry. Performance data from 35 completed projects and programs representing over $21.8 billion in total cost was collected and analyzed. The data analysis showed that the projects with high EVMS maturity and good EVMS environment outperformed those with low maturity and poor environment in key project performance measures. The contributions of this work includes: (1) developing definitions for EVM, EVMS and other research related terms, (2) determining the gaps in the EVMS literature, (3) determining the EVMS state of the practice in the industry, (4) developing a scalable rating system to measure the EVMS maturity and environment, (5) providing quantified evidence on the impact of EVMS maturity and environment on project performance, and (6) providing guidance to practitioners to gauge their EVMS maturity and environment for an enhanced project and program management integration and performance.
ContributorsAramali, Vartenie Mardiros (Author) / Gibson Jr., George Edward (Thesis advisor) / El Asmar, Mounir (Committee member) / Parrish, Kristen (Committee member) / Arizona State University (Publisher)
Created2022
Description
Aggressive and violent behavior is expressed differently across development, but for some adolescents, this behavior leads to criminal justice involvement through arrests and incarceration. Further, according to the biopsychosocial model, aggressive behavior is influenced by both genetics and the environment. This study sought to examine the differential impacts of early childhood environmental cumulative risk and genetic risk on the developmental cascade from middle childhood behavioral aggression and lack of control to adolescent antisocial behavior or callous-unemotional traits, to emerging adult involvement with the criminal justice system, and whether the effects of risk were mitigated by receiving the Family Check-Up (FCU) prevention program in childhood. The sample included high-risk youth (N = 731; 50% female, 50% White, 28% Black, 13% Hispanic, 9% Indigenous, Native Hawaiian, or Asian; of these 13% were multiracial; Mincome = $28,993; representative 515 genotyped) involved in a randomized-controlled trial of the Family Check-Up and followed longitudinally across 11 waves from ages 2 through 19 years. Behavioral measures included parent-report of behavioral aggression and observational lack of control in middle childhood, self-report of antisocial behavior and callous-unemotional (CU) traits in adolescence, and self-report of involvement with the legal system at age 19. Results of longitudinal structural equation modeling (SEM) supported a developmental cascade from middle childhood behavioral aggression to antisocial behavior in adolescence to legal system involvement. Early cumulative environmental risk and polygenic risk tolerance (RT PGS) significantly predicted involvement with the legal system at age 19, while RT PGS also predicted antisocial behavior in adolescence. Further, intervention effects were found for the FCU, such that the FCU disrupted the effects of RT PGS and middle childhood aggression on antisocial behavior and CU traits in adolescence. This study showed that the FCU can mitigate polygenic risk, supporting the benefit of early psychosocial prevention programs. Importantly, this study showed initial evidence that prevention programs targeting early childhood conduct problems could potentially reduce rates of justice system involvement, including arrests and incarceration, by the age of 19.
ContributorsOstner, Savannah Grace (Author) / Lemery-Chalfant, Kathryn (Thesis advisor) / Tein, Jenn-Yun (Committee member) / Davis, Mary C (Committee member) / Arizona State University (Publisher)
Created2024
Description
Since the early 2000s the Rubik’s Cube has seen growing usage at speedsolving competitions and as an effective tool to teach Science, Technology, Engineering, Mathematics (STEM) topics at hundreds of schools and universities across the world. Recently, cube manufacturers have begun embedding sensors to enable digital face tracking. The live feedback from these so called “smartcubes” enables a new wave of immersive solution tutorials and interactive educational games using the cube as a controller. Existing smartcube software has several limitations. Manufacturers’ applications support only a narrow set of puzzle form factors and application platforms, fragmenting the ecosystem. Most apps require an active internet connection for key features, limiting where users can practice with a smartcube. Finally, existing applications focus on a single 3x3x3connection, losing opportunities afforded by new form factors. This research demonstrates an open-source smartcube application which mitigates these limitations. Particular attention is given to creating an Application Programming Interface (API) for smartcube communication and building representative solve analysis tools. These innovations have included successful negotiations to re-license existing open-source Rubik’sCube software projects to support deployment on multiple platforms, particularly iOS. The resulting application supports smartcubes from three manufacturers, runs on two platforms (Android and iOS), functions entirely offline after an initial download of remote assets, demonstrates concurrent connections with up to six smartcubes, and supports all current and anticipated smartcube form factors. These foundational elements can accelerate future efforts to build smartcube applications, including automated performance feedback systems and personalized gamification of learning experiences. Such advances will hopefully enhance the Rubik’s Cube’s value both as a competitive toy and as a pedagogical tool in educational institutions worldwide.
ContributorsHale, Joseph (Author) / Bansal, Ajay (Thesis advisor) / Heinrichs, Robert (Committee member) / Gary, Kevin (Committee member) / Arizona State University (Publisher)
Created2023
Description
A reform movement in the United States has focused on STEM education and 21st century soft skills such as critical thinking, communication, collaboration, and creativity. This spotlight on STEM instruction provided an opportunity to explore how K-14 STEM teacher participants perceived a Design Thinking Instructional Problems (DTIP) approach to developing instructional lessons. The study used a convergent parallel mixed-methods design with a survey instrument and a multiple case study focused on K-14 in-service STEM teachers. Data were collected from teacher participants during two five-week summer Research Experience for Teachers (RET) programs as part of two separate National Science Foundation (NSF) funded Engineering Research Centers (ERC) located at a large southwestern university in the United States (n=16). The study was conducted over three phases. During Phase I and II, teacher participants experienced a Design Thinking Overview workshop and weekly DTIP professional development sessions to facilitate the development of an RET instructional lesson. Pre- and post-program DTIP surveys and background interviews were conducted with all teacher participants (n=16). From this original group, teacher participants were selected as cases. Implementation observations and post-implementation interviews were conducted with these case-teachers (n=10). The study included frequency analysis and descriptive statistics of survey data. Qualitative data were analyzed using direct interpretation, thematic analysis, and open coding with the constant comparative method. A variety of arrays, summaries, and matrices were used to visualize patterns across and within individual case-teacher results. All 16 teacher participants viewed themselves as designers solving complex instructional problems. All 16 teacher participants found the DTIP professional development sessions to have somewhat to very much provided additional value during their RET summer programs. Six of the 10 case-teachers perceived the DTIP model graphic as mostly to completely corresponding to the way in which they developed their RET instructional lesson. Lastly, eight of the 10 case-teachers chose to embed a Design Thinking student learning strategy into the RET instructional lesson they developed.
ContributorsElwood, Kristin (Author) / Savenye, Wilhelmina (Thesis advisor) / Jordan, Michelle E (Committee member) / Henriksen, Danah (Committee member) / Mishra, Punya (Committee member) / Arizona State University (Publisher)
Created2018