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Teaching as Practice: Blending the Intellectual and Moral in Pursuit of Science Teachers' Practical Knowledge
No full textThis study aimed to (a) explore and understand the intricacy of science teaching as a morally committed practice engaging teachers' practical knowledge; (b) explore science teacher practical knowledge by probing and understanding teachers' interpretations, commitments, and dialectic interactions between them; and (c) scrutinize science teachers' actions in terms of their interpretations and commitments as they go about realizing 'internal goods' of their practice and resolving dilemmas of everyday science teaching practice. Case studies of three physical science teachers in different socioeconomic contexts in Lebanon were conducted using ethnographic methods of indepth dialogues, observation, and artifact analysis. An interpretive approach to data analysis was adopted to ensure that the generated themes and assertions reflected participant teachers' interpretation and commitments. A commitment of preparing students for the official exams and doing well in them prevailed across the three contexts. This commitment originated from the teachers' interpretations of their duty as 'good' teachers who will not let students and the school down. In the public schools, teachers saw that students' passing the Brevet exams gains them a right of passage to a safe zone. In the private school, the teacher saw her duty to have student attain high grades in preparation for their future educational and career plans. Each teacher's case was described in terms of a teacher's standing commitments, associated interpretations, and manifestations in action. A characterization for each teacher's practice was offered in light of interactions between commitments, interpretations and actions. Characterizations that emerged included: a disciplining governess, role model with missionary tendencies, and good employee with a mission. The concept of gap-closing (between interpretations and commitments) was used to explain development of teachers' practical knowledge. Nature of gap closing and its forms are discussed in light of the case studies. A view of teachers' knowledge involving a practical moral dimension is discussed utilizing the concept of 'phronesis.' Phronetic knowledge is compared with other forms of teacher knowledge within major science education research traditions: Constructivism and sociocultural perspectives. Finally, implications of such a view of knowledge are presented as they pertain to professional development, teacher education, and research in science education.Made available in DSpace on 2015-09-25T19:54:29Z (GMT). No. of bitstreams: 2
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Previous issue date: 2006Embargo set by: Seth Robbins for item 81198
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only316 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006
Graphical Models for Video Analysis
No full textU of I OnlyTherefore, this work is concerned with the design of fast, robust graphical models capable of unsupervised performance. The validity, effectiveness, and potential uses of the proposed approaches are verified with experiments that use real video sequences in several important applications, such as stabilization, layering, video surveillance, clustering and light modeling.Made available in DSpace on 2015-09-25T20:09:37Z (GMT). No. of bitstreams: 2
license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5)
3347397.pdf: 4409605 bytes, checksum: 72b4b0b5fb9851ff633300b021602f38 (MD5)
Previous issue date: 2008Embargo set by: Seth Robbins for item 82395
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDs83 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008
Fabrication of Metal and Organic Nanostructures on Silicon(100) With Scanning Tunneling Microscope-Based Lithography
No full text"The scanning tunneling microscope (STM) has been employed for both atomic-scale characterization and modification of surfaces. The STM, for example, can be used to desorb hydrogen or deuterium from nanometer-sized regions of the H-passivated or D-passivated Si(100)-2 x 1 surface, resulting in nanometer-sized ""templates"" which can then be reacted with various chemical species. Previous work has demonstrated selective oxidation and nitridation of STM- patterned areas by exposing the patterned surface to O2 and NH3, respectively. Here, this technique is applied to the fabrication of organic and metal-containing nanostructures on the Si(100) surface. Norbornadiene, an olefinic organic molecule, is shown to react selectively with STM-depassivated areas to form nanometer-sized regions with a norbornadiene adlayer. Metal CVD (chemical vapor deposition) precursor molecules are also shown to react selectively with STM-depassivated areas. The reaction of such areas with an Al CVD precursor and with a CVD nucleation promoter (TiCl4) is discussed, and preliminary results with other metal precursor molecules are described."Made available in DSpace on 2015-09-25T20:10:17Z (GMT). No. of bitstreams: 2
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Previous issue date: 1998Embargo set by: Seth Robbins for item 82538
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only81 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1998
Control of Chey-P Levels in the Chemotactic Sensory Transduction Cascade of Bacillus Subtilis
No full textBacteria sense their environment and respond to it in order to enhance their chance for survival. Motility is one output created that enables bacteria to colonize in optimal conditions. Since environments are ever changing, the signal transduction mechanism controlling this behavior has to be able to respond on a time scale of seconds. This is achieved by phosphorylation of an intracellular signaling molecule CheY (to generate CheY-P) in response to changing environments. As important is the rapid dephosphorylation of this protein, to reset the system and prepare it for new signals. The flagella proteins FliM and FliY are the interaction target for CheY-P in Bacillus subtilis. Binding of CheY-P to FliM induces a counterclockwise rotation of the motility apparatus, the flagella. FliM in Escherichia coli was previously demonstrated to have the same function. FliY on the other hand is not found in E. coli. Phenotypes of a mutant incapable of binding CheY-P led to the hypothesis that FliY actively dephosphorylates CheY-P. This hypothesis was verified by incubating CheY with FliY in vitro and following the rate of CheY-P hydrolysis. CheC, which shares homology with the N-terminal domain of FliY, also shares its function to dephosphorylate CheY-P. With the knowledge that there are two proteins in the B. subtilis chemotaxis signal transduction cascade, an attempt was made to clarify the specific roles of these two proteins. Specific activities and per cell copy number were measured for both these proteins. FliY is expressed at much higher levels than CheC. The activity of CheC is relatively low compared to that of FliY, but this activity was shown to be enhanced 5-fold by the chemotaxis protein CheD. In vivo, a double mutant lacking cheC and the region of fliY that encodes the CheY-P binding domain is almost completely smooth swimming, implying that these cells contain very high levels of CheY-P. CheC appears to be primarily involved in restoring normal CheY-P levels following the addition of attractant, whereas FliY seems to act on CheY-P constitutively. A model for how FliY, CheC, and CheD work together to regulate CheY-P levels in the bacterium is proposed.Made available in DSpace on 2015-09-25T22:28:00Z (GMT). No. of bitstreams: 2
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Previous issue date: 2004Embargo set by: Seth Robbins for item 86087
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only117 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004
The Effect of Noise Bandwidth and Modulation on Signal Detection for Single Neurons in the Frog Auditory Midbrain
No full textNatural auditory scenes, like frog choruses, comprise multiple sound sources like individual vocalizations and background noise that overlap in the time- and frequency domains. Detection of sound in such a background is challenging, and depends on the bandwidth and modulation depth of the background noise. A process that facilitates target detection in noisy environments is comodulation masking release (CMR), whereby the detectability improves when the noise is coherently modulated across a wide frequency range. Here, we examined how noise attributes, such as bandwidth and modulation, influence the detection threshold for single neurons in response to a synthetic advertisement call. Additionally, seasonal effects on the response properties of neurons were also studied. Extracellular recordings were made from single neurons in the auditory midbrain (torus semicircularis) of the frog (Rana pipiens pipiens). In response to the synthetic advertisement call, broadcast via a loudspeaker, torus neurons displayed differences in frequency tuning and temporal response properties in the different seasons. In winter, response latency increased and time locking decreased, while no significant differences in threshold and response rates were observed. To determine whether there is a neural basis for CMR in the frog central auditory system, noise was added to the target. It was found that both unmodulated and modulated noise generally increased the signal detection threshold, however, sinusoidally modulated noise elevated this threshold to a lesser extent. When the noise bandwidth was increased, the probe detection threshold decreased for modulated noise for 15% of the TS neurons. These results suggest that CMR is present in the frog. The temporal properties of the responses observed in 11% of the cells showed response only to tone pulses placed in the troughs of modulated noise; coincidence with peaks in the noise suppressed the probe response. This supports the dip-listening hypothesis, which presumes that the presence of gaps in the noise across frequency bands is used to enhance signal detectability. However, suppression of the response to the noise by the probe was also observed, supporting a noise-suppression mechanism. The neural response properties suggest that frogs may exploit across channel modulation to improve signal detection in noise.Made available in DSpace on 2015-09-25T22:46:04Z (GMT). No. of bitstreams: 2
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Previous issue date: 2004Embargo set by: Seth Robbins for item 86716
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only148 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004
Race to the Bottom or Move to the Middle? Globalization and Welfare Regime Transformation in the Developing World
No full textMy findings demonstrate that the variations of social welfare systems in the developing world are rooted in the conflicting dynamics of industrialization and globalization. Industrialization in the developing world has an expansionary effect on welfare expenditures as it entails risks that fuel the demand for protection. The impact of globalization, however, is multifaceted. Globalization induces a structural change of preferences among major social actors with regards to social protection, which, in turn, leads to the fundamental change of policymaking strategies of politicians. Specifically, globalization has an equalization effect on the preferences among social actors, as the risks associated with economic openness become increasingly similar to social groups from different sectors. The changing structure of social preferences at the demand side fundamentally alters the incentives of policymakers at the supply side whose ultimate concern is to maximize political support from contending social groups that have been affected unevenly by globalization. The result is a trend towards an equilibrium welfare policy outcome in which the marginal support from different groups is equally weighed and politicians compensate groups only partially. In this equilibrium welfare regime, globalization imposes downward pressures on inefficient welfare programs but also induces governments to establish and expand social safety nets that are critical for market competition and sustainable development. Arguments are tested through both quantitative cross-national analysis and comparative case studies of China, Brazil, and South Korea.Made available in DSpace on 2015-09-25T20:49:32Z (GMT). No. of bitstreams: 2
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Previous issue date: 2010Embargo set by: Seth Robbins for item 83871
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only255 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2010
Day-to-Day Variation in the Feed Consumption of Dairy Cows in Early Lactation
No full textA final 9-wk experiment studied the performance of 24 Holstein cows during the transition period. Cows were assigned to either a control or a liquid-flavored (0.52 ml/kg of feed) totally mixed ration in a randomized complete-block design. Weekly means of DMI, milk production, and body weight were analyzed. Individual cow daily DMI data were fitted to the exponential model. There was no effect of treatment on these variables or the fractional rates of increase in DMI. Multiple regression analysis suggested that more body weight was mobilized per unit increase in 3.5% fat-corrected milk in cows fed the control diet, and those cows tended to be in more negative energy balance than cows fed the flavored diet. Parameters of both the exponential and cosinor models were associated with various pre- and post-parturn production variables. Plasma progesterone concentrations were positively correlated with DMI. It was concluded that feeding the flavor improved the energy balance of cows in early lactation and may reduce the risk of health or reproductive problems. Overall, the exponential model was consistently more accurate and robust than the current NRC equation. Together with cosinor model it explained most of the day-to-day variation in the feed consumption of dairy cows in early lactation. The association between plasma progesterone and DMI was also confirmed.Made available in DSpace on 2015-09-25T21:08:02Z (GMT). No. of bitstreams: 2
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Previous issue date: 2001Embargo set by: Seth Robbins for item 84819
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only170 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2001
Synthesis and Determination of the Absolute Configuration of the Bicyclic Guanidine Core of Batzelladine A and the Development of a Novel [4+2] Inverse Electron Demand Hetero Diels -Alder Cycloaddition and Its Application Toward the Synthesis of the Tricyclic Guanidine Fragment Within Batzelladine A
No full textOur developments toward the total synthesis batzelladine A are presented in this study. This includes the construction of the bicyclic guanidine portion including elucidation of the absolute configuration of the bicyclic guanidine and the development of a novel [4+2] inverse electron demand hetero Diels-Alder cycloaddition amendable for synthesis of the tricyclic guanidine portion. These studies culminated in the first synthesis of the bicyclic guanidine core within batzelladine A, which was demonstrated by accessing in enantiospecific fashion a suitably protected form of the bicyclic core employing L -aspartic acid as the starting material. The development of a novel strategy for accessing the tricyclic guanidine portion within batzelladine A is also included within this study. We have identified a novel [4+2] inverse electron demand hetero Diels-Alder cycloaddition between alpha,beta-unsaturated carbodiimides and cyclic thioimidates for access to functionalized guanidines which were shown to be possible advanced intermediates for the functionalized tricyclic guanidine contained within batzelladine A.Made available in DSpace on 2015-09-25T22:12:45Z (GMT). No. of bitstreams: 2
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Previous issue date: 2002Embargo set by: Seth Robbins for item 85358
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only212 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2002
Development of Synthetic Nanofiltration Membranes for Water Treatment
No full textEmbargo set by: Seth Robbins for item 85568
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only118 p.Synthetic nanofiltration (NF) membrane technologies are capable of removing colloidal, organic, and multivalent ionic contaminants in natural water resources and are considered an attractive means for providing safe drinking water due to their much lower energy consumption compared to reverse osmosis and conventional distillation technologies. State-of-the-art commercial NF membranes have limited types based on either Loeb-Sourirajan or thin film composite anisotropic membranes. For these reasons, NF membrane development in other preparation methods and active layer chemical compositions to improve membrane productivity and cost-effectiveness has tremendous growth in the global water treatment market. This dissertation describes the exploration of a new NF membrane preparation approach based on small molecule pre-deposition and subsequent in situ stitching. Shape-persistent macrocycles (phenylene-ethynylene pentamer, hexamer, heptamer, benzocyclyne derivatives) and polyaromatic hydrocarbons (HPB, FIBC derivatives) of nanoscale dimension were designed and synthesized via cyclooligomerization reactions, serving as potential molecular building blocks for construction of membrane active layers. Among these molecules, rigid star amphiphiles (RSAs) with a series of hydrophobicity and functional properties were selected to fabricate a new generation of NF membranes. Membranes were prepared by direct percolation of methanol solutions of the RSAs through an asymmetric polyethersulfone support film that had been previously conditioned with methanol and cross-linked polyvinyl alcohol. The resulting RSA membranes (RSAMs) have been shown to exhibit significantly enhanced water permeability while maintaining high rejection of water contaminants compared to commercial NF membranes. Characterization results from confocal microscopy and Rutherford back-scattering spectrometry provided visual and semi-quantitative evidence suggesting the formation of an ultra-thin active layer of RSA molecules atop the modified support after lining its nano-pores with sizes similar to those of the RSAs. Such active layer constitution was found crucial for rejecting organic contaminants and achieving high water flux as a result of the reduced active layer thickness compared to that of commercial NF membranes. In addition, SEM and AFM images revealed that the new membranes achieved a uniform, flat surface which might help alleviate the fouling problems associated with rough membrane surfaces of commercial NF membranes. In situ stitching of RSAs to stabilize active layers by Cu(I)-catalyzed azide-alkyne cycloaddition reaction and UV-induced nitrene C-H bond insertion reaction were conducted, however, preliminary results revealed these attempts were unsuccessful when applied to tiny amounts of crosslinkers under wet conditions in a membrane system. Current research efforts are focusing on varying the in situ chemical stitching methods and conditions to construct robust membrane active layers preserving any inherent selectivity that the RSA building blocks might have. The molecular deposition approach is expected to provide an alternative, versatile channel to the creation of ultra-thin membrane active layers with tunable chemical compositions to remove challenging water contaminants while producing high water fluxes.Made available in DSpace on 2015-09-25T22:13:48Z (GMT). No. of bitstreams: 2
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Previous issue date: 2007Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007
"Manuel Rodrigues Coelho's ""Flores De Musica"": Style and Performance Practice"
No full textManuel Rodrigues Coelho's Flores de musica (1620) holds a particularly important place in the history of Iberian keyboard music of the sixteenth and seventeenth centuries. As the first printed source of instrumental music in Portugal and one of the largest collections to be produced on the Iberian peninsula during the period, Flores de musica marks a turning point in musical style between late Renaissance and early Baroque practices, especially in the tentos, which form a link in the evolution of the Spanish tiento, beginning with those of Mudarra and Cabezon and culminating in the works of Correa and Cabanilles. This study of Flores de musica (1) provides the first complete English translation of Coelho's Foreword and Specific Instructions, (2) identifies a number of stylistic influences absorbed from contemporary musicians from elsewhere on the European continent, (3) analyzes selected tentos in light of then-current ideas about tonal and rhythmic organization, and most importantly, (4) provides the reader with a sufficient amount of information on performance practice techniques, both musical and liturgical, so that the pieces contained in Flores de musica may be rendered as authentically as possible on modern instruments.Made available in DSpace on 2015-09-25T22:53:19Z (GMT). No. of bitstreams: 2
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Previous issue date: 2004Embargo set by: Seth Robbins for item 87027
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDsRestricted to the U of I community idenfinitely during batch ingest of legacy ETDsU of I Only111 p.Thesis (A.Mus.D.)--University of Illinois at Urbana-Champaign, 2004