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Promoting meaningful uses of technology in a middle school

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Federal education policies call for school district leaders to promote classroom technology integration to prepare students with 21st century skills. However, schools are struggling to integrate technology effectively, with students often reporting that they feel like they need to power

Federal education policies call for school district leaders to promote classroom technology integration to prepare students with 21st century skills. However, schools are struggling to integrate technology effectively, with students often reporting that they feel like they need to power down and step back in time technologically when they enter classrooms. The lack of meaningful technology use in classrooms indicates a need for increased teacher preparation. The purpose of this study was to investigate the impact a coaching model of professional development had on school administrators` abilities to increase middle school teachers` technology integration in their classrooms. This study attempted to coach administrators to develop and articulate a vision, cultivate a culture, and model instruction relative to the meaningful use of instructional technology. The study occurred in a middle school. Data for this case study were collected via administrator interviews, the Principal`s Computer Technology Survey, structured observations using the Higher Order Thinking, Engaged Learning, Authentic Learning, Technology Use protocol, field notes, the Technology Integration Matrix, teacher interviews, and a research log. Findings concluded that cultivating change in an organization is a complex process that requires commitment over an extended period of time. The meaningful use of instructional technology remained minimal at the school during fall 2010. My actions as a change agent informed the school`s administrators about the role meaningful use of technology can play in instruction. Limited professional development, administrative vision, and expectations minimized the teachers` meaningful use of instructional technology; competing priorities and limited time minimized the administrators` efforts to improve the meaningful use of instructional technology. Realizing that technology proficient teachers contribute to student success with technology, it may be wise for administrators to incorporate technology-enriched professional development and exercise their leadership abilities to promote meaningful technology use in classrooms.

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2011

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The human capital accumulation of young mothers: the relationship with father involvement

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This study utilized ecological theory and social exchange theory to examine how father involvement effects the human capital accumulation of young mothers. This study used data from a sub-sample of young mothers taken from the Healthy Families Arizona longitudinal evaluation

This study utilized ecological theory and social exchange theory to examine how father involvement effects the human capital accumulation of young mothers. This study used data from a sub-sample of young mothers taken from the Healthy Families Arizona longitudinal evaluation (N = 84). The participants in the sub-sample were between 13 and 21 years of age. Using a random effects regression model, it was found that father involvement negatively affects a young mother's school attendance over time. The probability of a mother attending school when the father is involved decreases by 12%. It was also found that for the average age mother (19 years of age), the probability of attending school decreases by 59% every additional year. Furthermore, for a mother with an average number of children (one child), every additional child she has decreases the probability of attending school by 24%. In addition it was found that for the average age mother (19 years of age) every additional year, the likelihood of being employed increases 2.9 times, and for a mother with an average number of children (one child) every additional child decreases the likelihood of employment by .88 times.

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2011

Surface stress during electro-oxidation of carbon monoxide and bulk stress evolution during electrochemical intercalation of lithium

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This work investigates in-situ stress evolution of interfacial and bulk processes in electrochemical systems, and is divided into two projects. The first project examines the electrocapillarity of clean and CO-covered electrodes. It also investigates surface stress evolution during electro-oxidation of

This work investigates in-situ stress evolution of interfacial and bulk processes in electrochemical systems, and is divided into two projects. The first project examines the electrocapillarity of clean and CO-covered electrodes. It also investigates surface stress evolution during electro-oxidation of CO at Pt{111}, Ru/Pt{111} and Ru{0001} electrodes. The second project explores the evolution of bulk stress that occurs during intercalation (extraction) of lithium (Li) and formation of a solid electrolyte interphase during electrochemical reduction (oxidation) of Li at graphitic electrodes. Electrocapillarity measurements have shown that hydrogen and hydroxide adsorption are compressive on Pt{111}, Ru/Pt{111}, and Ru{0001}. The adsorption-induced surface stresses correlate strongly with adsorption charge. Electrocatalytic oxidation of CO on Pt{111} and Ru/Pt{111} gives a tensile surface stress. A numerical method was developed to separate both current and stress into background and active components. Applying this model to the CO oxidation signal on Ru{0001} gives a tensile surface stress and elucidates the rate limiting steps on all three electrodes. The enhanced catalysis of Ru/Pt{111} is confirmed to be bi-functional in nature: Ru provides adsorbed hydroxide to Pt allowing for rapid CO oxidation. The majority of Li-ion batteries have anodes consisting of graphite particles with polyvinylidene fluoride (PVDF) as binder. Intercalation of Li into graphite occurs in stages and produces anisotropic strains. As batteries have a fixed size and shape these strains are converted into mechanical stresses. Conventionally staging phenomena has been observed with X-ray diffraction and collaborated electrochemically with the potential. Work herein shows that staging is also clearly observed in stress. The Li staging potentials as measured by differential chronopotentiometry and stress are nearly identical. Relative peak heights of Li staging, as measured by these two techniques, are similar during reduction, but differ during oxidation due to non-linear stress relaxation phenomena. This stress relaxation appears to be due to homogenization of Li within graphite particles rather than viscous flow of the binder. The first Li reduction wave occurs simultaneously with formation of a passivating layer known as the solid electrolyte interphase (SEI). Preliminary experiments have shown the stress of SEI formation to be tensile (~+1.5 MPa).

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2011

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Analysis of nucleosome dynamics by fluorescence correlation spectroscopy

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Nucleosomes are the basic repetitive unit of eukaryotic chromatin and are responsible for packing DNA inside the nucleus of the cell. They consist of a complex of eight histone proteins (two copies of four proteins H2A, H2B, H3 and

Nucleosomes are the basic repetitive unit of eukaryotic chromatin and are responsible for packing DNA inside the nucleus of the cell. They consist of a complex of eight histone proteins (two copies of four proteins H2A, H2B, H3 and H4) around which 147 base pairs of DNA are wrapped in ~1.67 superhelical turns. Although the nucleosomes are stable protein-DNA complexes, they undergo spontaneous conformational changes that occur in an asynchronous fashion. This conformational dynamics, defined by the "site-exposure" model, involves the DNA unwrapping from the protein core and exposing itself transiently before wrapping back. Physiologically, this allows regulatory proteins to bind to their target DNA sites during cellular processes like replication, DNA repair and transcription. Traditional biochemical assays have stablished the equilibrium constants for the accessibility to various sites along the length of the nucleosomal DNA, from its end to the middle of the dyad axis. Using fluorescence correlation spectroscopy (FCS), we have established the position dependent rewrapping rates for nucleosomes. We have also used Monte Carlo simulation methods to analyze the applicability of FRET fluctuation spectroscopy towards conformational dynamics, specifically motivated by nucleosome dynamics. Another important conformational change that is involved in cellular processes is the disassembly of nucleosome into its constituent particles. The exact pathway adopted by nucleosomes is still not clear. We used dual color fluorescence correlation spectroscopy to study the intermediates during nucleosome disassembly induced by changing ionic strength. Studying the nature of nucleosome conformational change and the kinetics is very important in understanding gene expression. The results from this thesis give a quantitative description to the basic unit of the chromatin.

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2011

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Lesson study and the co-construction of pedagogical knowledge among secondary specialty teachers

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Teacher learning in the workplace is situated within a complex context involving the individual and multiple aspects of an educational organization. The present action research study uses a socio-constructionist inquiry lens to further research the local and multifaceted nature of

Teacher learning in the workplace is situated within a complex context involving the individual and multiple aspects of an educational organization. The present action research study uses a socio-constructionist inquiry lens to further research the local and multifaceted nature of professional learning in schools. The goal is to re-conceptualize professional development away from reductionist approaches that assume teacher practice can be isolated, packaged, and directly transferable into the classroom. The present study examines how lesson study can structure interdisciplinary professional learning to address the current gap in the literature regarding professional development of secondary specialty teachers. Five teachers participated in two lesson study cycles for a period of 13-weeks. This study focused on how teachers co-construct pedagogical knowledge and the extent to which they make changes to their practice. Using a sequential mixed methods research design, this study collected qualitative and quantitative data in three phases. In the initial phase, participants completed a demographical survey and shared a digital ethnography of their philosophy of teaching. Phase two consisted of video recordings for two lesson study cycles. Phase three involved a second survey and semi-structured interviews. Classroom observations were conducted during the first and last phase of the study. All qualitative data was analyzed inductively using open and thematic coding. Cross-case analysis was employed at the analysis stage to integrate data tools for the purpose of complementarity. Results suggest lesson study was an effective, job-embedded model that supports active and continuous professional development that is sustained and transferrable to the classroom. The type of disposition reported and displayed by teachers changed positively over time having transformational effects in the depth of relationships among teachers, increasing co-creation of pedagogical knowledge, and increasing reflectiveness. Teachers' level of openness to learning related to higher levels of effective practices implemented during lessons. Further research is needed to examine the ways in which teacher disposition influences professional learning when secondary specialty teachers engage in lesson study.

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2014

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A measure of goodness: art teacher identity as a measure of quality

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ABSTRACT This qualitative study examines how high school art teachers conceive of being a good art teacher. Motivated by my own experiences as an art teacher, I designed this study to add teachers' voices to the conversation surrounding quality in

ABSTRACT This qualitative study examines how high school art teachers conceive of being a good art teacher. Motivated by my own experiences as an art teacher, I designed this study to add teachers' voices to the conversation surrounding quality in education. My research design included a narrative strand and an arts-based strand. In the narrative strand, I interviewed and observed 12 high school art educators from a major city in the southwest. I conducted an autoethnographic reflection exploring my connection to the research topic and research process. In the arts-based strand I used fiber-arts to further understand my topic. I wrote this dissertation using a narrative approach, blending the traditional research format, voices of participants, and my autoethnographic reflection. I included the results of my arts-based approach in the final chapter. Findings suggest that the teachers in this study conceptualize being a good art teacher as a process of identity construction. Each of the teachers understood what it meant to be a good art teacher in unique ways, connected to their personal experiences and backgrounds. As the teachers engaged in identity work to become the kind of art teacher they wanted to be, they engaged in a process of identity construction that consisted of four steps. I propose a model of identity construction in which the teachers chose teaching practices, evaluated those practices, identified challenges to their identities, and selected strategies to confirm, assert, or defend their desired identities. The findings have implications for teachers to become reflective practitioners; for teacher educators to prepare teachers to engage in reflective practices; and for administrators and policy makers to take into account the cyclical and personal nature of identity construction. This study also has implications for further research including the need to examine the dispositions of art teachers, teachers' evolving conceptions of what it means to be a good art teacher, and the effect labeling teachers' quality has on their identity construction.

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2014

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Essays in international economics and development

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This dissertation consists of three essays that broadly deal with the international economics and development. The first chapter provides empirical evidence of the prevalence and importance of intangible capital transfer within multinational corporations (MNCs). Using a unique data set of

This dissertation consists of three essays that broadly deal with the international economics and development. The first chapter provides empirical evidence of the prevalence and importance of intangible capital transfer within multinational corporations (MNCs). Using a unique data set of Korean multinational foreign affiliates, I find that most of the foreign affiliates have managers transferred from their parent, while almost half are isolated from the parent in terms of physical trade. Furthermore, the transferred managers are positively associated with labor productivity, while physical trade from the parent is less so. I consider two possibilities for this productivity effect: (1) the managers transferred from the parent are simply more efficient than native managers; and (2) they provide knowledge that increases the productivity of all inputs. I find that the latter is consistent with the data. My findings provide evidence that transferring managers from the parent is a main source of benefit from foreign direct investment (FDI) to foreign affiliates because the managers transfer firm-specific knowledge. The second chapter analyzes importance role of service or other sectors for economic growth of manufacturing. Productivity in agriculture or services has long been understood as playing an important role in the growth of manufacturing. In this paper we provide an endogenous growth model in which manufacturing growth is stimulated by the non-manufacturing sector that provides goods used for both research and final consumption. The model permits to evaluatation of two policy options for stimulating manufacturing growth: (1) a country imports more non-manufacturing goods from a foreign country with a higher productivity; or (2) the country increases productivity of domestic non-manufacturing. We find that both policies increase welfare of the economy, but depending on the policy the manufacturing sector responses differently. Specifically, employment and value added in manufacturing rise with policy (1), but contract with policy (2). Therefore, specialization through importing non-manufacturing goods explains how some Asian economies experience fast growth in the manufacturing sector without progress in the other sectors. The third chapter tests for the importance of composition effects in affecting levels and changes of education wage premiums. In this paper I revisit composition effects in the context of Korea. Korea's large and rapid expansion of education makes it an ideal place to look for composition effects. A large, policy-induced increase in attainment in the 1980s offers additional scope for identifying composition effects. I find strong evidence that the policy-induced expansion of education lowered education wage premiums for the affected cohorts, but only weak evidence that the trend expansion of education lowered education wage premiums.

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2014

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Teacher stressors in an Arizona urban school district

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Teachers have the one of the most difficult, yet most rewarding jobs to guide our impressionable youth into academically prepared independent thinkers. This undertaking requires a commitment, as well as an enormous effort that can oftentimes be overwhelming. Teaching has

Teachers have the one of the most difficult, yet most rewarding jobs to guide our impressionable youth into academically prepared independent thinkers. This undertaking requires a commitment, as well as an enormous effort that can oftentimes be overwhelming. Teaching has been found to be a stressful profession for several decades with the potential concern of negative consequences for both teachers and students. The purpose of this study was to view mutual influences that affected the stress levels of urban teachers, as well as gather possible solutions to help alleviate some areas of stress. This study evaluated an urban school district in Arizona to uncover existing stressors for elementary teachers. Through qualitative analysis, this study utilized focus group interviews within this urban district, which consisted of 20 teachers in various grade levels. Four to five teachers formed each focus group, where participants responded to six open-ended questions in a candid setting. Using the grounded theory, major and minor themes emerged as a result of teacher responses that revealed trends and commonalities. Additionally, participants relayed their suggestions to mitigate some of these stressors. This study revealed that the some of the stressors that surfaced were common to the entire group, while some grade level subgroups differed in areas of stress. The suggestion to implement purposeful support systems to improve the stress of teachers was recommended with the proposal to reexamine the results for their effectiveness in future studies.

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2013

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Synthesis and characterization of thionated reduced graphene oxides and their thin films

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Thiol functionalization is one potentially useful way to tailor physical and chemical properties of graphene oxides (GOs) and reduced graphene oxides (RGOs). Despite the ubiquitous presence of thiol functional groups in diverse chemical systems, efficient thiol functionalization has been challenging

Thiol functionalization is one potentially useful way to tailor physical and chemical properties of graphene oxides (GOs) and reduced graphene oxides (RGOs). Despite the ubiquitous presence of thiol functional groups in diverse chemical systems, efficient thiol functionalization has been challenging for GOs and RGOs, or for carbonaceous materials in general. In this work, thionation of GOs has been achieved in high yield through two new methods that also allow concomitant chemical reduction/thermal reduction of GOs; a solid-gas metathetical reaction method with boron sulfides (BxSy) gases and a solvothermal reaction method employing phosphorus decasulfide (P4S10). The thionation products, called "mercapto reduced graphene oxides (m-RGOs)", were characterized by employing X-ray photoelectron spectroscopy, powder X-ray diffraction, UV-Vis spectroscopy, FT-IR spectroscopy, Raman spectroscopy, electron probe analysis, scanning electron microscopy, (scanning) transmission electron microscopy, nano secondary ion mass spectrometry, Ellman assay and atomic force microscopy. The excellent dispersibility of m-RGOs in various solvents including alcohols has allowed fabrication of thin films of m-RGOs. Deposition of m-RGOs on gold substrates was achieved through solution deposition and the m-RGOs were homogeneously distributed on gold surface shown by atomic force microscopy. Langmuir-Blodgett (LB) films of m-RGOs were obtained by transferring their Langmuir films, formed by simple drop casting of m-RGOs dispersion on water surface, onto various substrates including gold, glass and indium tin oxide. The m-RGO LB films showed low sheet resistances down to about 500 kΩ/sq at 92% optical transparency. The successful results make m-RGOs promising for applications in transparent conductive coatings, biosensing, etc.

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2013

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Novel strategies for producing proteins with non-proteinogenic amino acids

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The biological and chemical diversity of protein structure and function can be greatly expanded by position-specific incorporation of non-natural amino acids bearing a variety of functional groups. Non-cognate amino acids can be incorporated into proteins at specific sites by using

The biological and chemical diversity of protein structure and function can be greatly expanded by position-specific incorporation of non-natural amino acids bearing a variety of functional groups. Non-cognate amino acids can be incorporated into proteins at specific sites by using orthogonal aminoacyl-tRNA synthetase/tRNA pairs in conjunction with nonsense, rare, or 4-bp codons. There has been considerable progress in developing new types of amino acids, in identifying novel methods of tRNA aminoacylation, and in expanding the genetic code to direct their position. Chemical aminoacylation of tRNAs is accomplished by acylation and ligation of a dinucleotide (pdCpA) to the 3'-terminus of truncated tRNA. This strategy allows the incorporation of a wide range of natural and unnatural amino acids into pre-determined sites, thereby facilitating the study of structure-function relationships in proteins and allowing the investigation of their biological, biochemical and biophysical properties. Described in Chapter 1 is the current methodology for synthesizing aminoacylated suppressor tRNAs. Aminoacylated suppressor tRNACUAs are typically prepared by linking pre-aminoacylated dinucleotides (aminoacyl-pdCpAs) to 74 nucleotide (nt) truncated tRNAs (tRNA-COH) via a T4 RNA ligase mediated reaction. Alternatively, there is another route outlined in Chapter 1 that utilizes a different pre-aminoacylated dinucleotide, AppA. This dinucleotide has been shown to be a suitable substrate for T4 RNA ligase mediated coupling with abbreviated tRNA-COHs for production of 76 nt aminoacyl-tRNACUAs. The synthesized suppressor tRNAs have been shown to participate in protein synthesis in vitro, in an S30 (E. coli) coupled transcription-translation system in which there is a UAG codon in the mRNA at the position corresponding to Val10. Chapter 2 describes the synthesis of two non-proteinogenic amino acids, L-thiothreonine and L-allo-thiothreonine, and their incorporation into predetermined positions of a catalytically competent dihydrofolate reductase (DHFR) analogue lacking cysteine. Here, the elaborated proteins were site-specifically derivitized with a fluorophore at the thiothreonine residue. The synthesis and incorporation of phosphorotyrosine derivatives into DHFR is illustrated in Chapter 3. Three different phosphorylated tyrosine derivatives were prepared: bis-nitrobenzylphosphoro-L-tyrosine, nitrobenzylphosphoro-L-tyrosine, and phosphoro-L-tyrosine. Their ability to participate in a protein synthesis system was also evaluated.

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2013