VictorJuiz/thesis huggingface dataset:
An examination of the experiences which university teachers have in the process of incorporating computer-mediated instruction techniques into their courses

This qualitative study explores the experiences of and elucidates the processes involving twelve university faculty members in the incorporation of computer mediated instruction techniques (CMITs) into their teaching. The study uses a semi-structured interview guide to gather specific demographic and course information and to prompt the participants to reflect on the pros and cons of incorporating CMITs, support mechanisms for incorporation, and the implications for their teaching. It is evident from the literature and the comments of faculty members that the incorporation of CMITs involves a complex of processes. To help frame these processes, incorporation is viewed from three perspectives, i.e., the objectivist-constructivist continuum, instructional design, and diffusion of technology. While the participants do not talk in these terms, it is evident that they are moving to a student-focused approach in line with a constructivist viewpoint. They are also experimenting with new tools for their courses although there has not been a great deal of reflection on the impacts of these tools and techniques on course design. The experimentation and incorporation activities of these subjects can also be usefully examined in the framework of diffusion of innovation. The faculty members, from three Ontario universities, have at least one year of experience using CMITs and are diverse in regard to both their subject specialties and the techniques used. Their focus is on e-mail for communication and web pages for course management. All use, have used, or are familiar with presentation software, audio/video conferencing, course authoring templates, or special statistical or musical software. They are generally positively inclined to these but have reservations on further use and development. These concerns revolve around practical and policy issues, such as, that increasing e-mail access for students requires coping strategies for faculty; requiring students to have computers or high level computer skills may create barriers to learning; and, putting course materials on-line requires much clearer intellectual property rights and responsibilities. Even in the face of these concerns, as well as insufficient training support and/or poor technical infrastructures, these keen faculty members still forge ahead into uncharted territory.
Identification of anoxia-induced expression of HSP70 in Chrysemys picta belli hepatocytes

This study examines the expression of the 70 kDa heat shock protein (HSP70) in hepatocytes from 'Chrysemys picta belli' in response to various stresses, namely heat shock, anoxia, and exposure to heavy metals and peroxide. The effect of the A1 receptor agonist, N6-cyclopentyladenosine (CPA), and antagonist, 8-cyclopentyl-1,3-dipropyl-xanthine (DPCPX), on the expression of HSP70 during heat shock and anoxia were also investigated. HSP70 mRNA and protein were detected at temperatures ranging from 28°C-48°C. Temperatures above 48°C were injurious to the cells. Both heavy metal and peroxide exposure resulted in the expression of HSP70 mRNA and protein. Importantly, 1 to 6 h anoxia induced the expression of HSP70 mRNA and protein. DPCPX blocked the expression of both HSP70 mRNA and protein during anoxia. However, CPA failed to induce the expression of HSP70 during normoxia. DPCPX did not block the expression of HSP70 during heat shock. These data also suggest that the induction of HSP70 during anoxia may be A1R mediated, indicating that the expression of HSP70 can be induced via different pathways.
Towards a paradigm of the polylingual performance, linguistic and metalinguistic functioning in the Commedia dell'Arte

The verbal text of an Italian Commedia dell'Arte performance typically consisted of speeches improvised by the actors in the dialects of the regions of origin of its stock characters. Since the performances were generally aimed at audiences familiar with no more than one or two dialects or languages, commedia troupes had to rely on a non-verbal mechanism for making their "polylingual" theatre intelligible not only to Italian audiences but to the other European audiences for whom they performed. Communication of verbal meaning was achieved by means of an ostensive, gesturally and phonically expressive mode of speaking capable of making itself immediately clear. My purpose in this thesis is to give a systematic account of this mechanism, in so far as it can be gleaned from contemporary manuals and critical accounts of commedia performances, and to develop from that empirical base a formal model for the semantic structure of the multilingual theatrical speech that it sustains. In constructing this paradigm, I plan to refer to the work of the sixteenth- and seventeenth-century commedia players, the work of the ' Comédiens Italiens' in France, and to the work of Carlo Goldoni (1707-1793). In addition, I will draw key analytical concepts from Dario Fo's work on phonic communication in the commedia tradition. Maurice Merleau-Ponty's phenomenology of language and Mikhail Mikhailovich Bakhtin's theory of 'dialogism' and 'heteroglossia' will further inform the thesis and provide the theoretical and methodological approach for this work.
MT1-MMP in neutrophils, potential mechanism for collagenase activation

Matrix metalloproteinases (MMPs) are important enzymes in the destruction of extracellular matrices in periodontal diseases. One of these enzymes, MMP-8, is derived largely from neutrophils. The active form of MMP-8 is found in the gingival crevicular fluid of progressive periodontitis lesions but the mechanism by which the latent enzyme is converted to active forms in vivo is poorly understood. As activation of MMP-2 can be mediated by a membrane-bound MMP, membrane-type-1 MMP (MT1-MMP), I tested the hypothesis that MT-MMPs are expressed in neutrophils and can activate latent MMP-8. My objectives were: (1) to assess the presence and location of MT-MMP in peripheral blood neutrophils; (2) to determine if MT-MMPs can activate MMP-8. By RT- PCR, I found that human peripheral blood neutrophils expressed MT1-MMP mRNA. The plasma membrane and specific granule fractions of neutrophils were isolated by discontinuous Percoll gradients and from these fractions I found MT1-MMP in the plasma membrane fraction. Soluble biotinylated collagen assays showed some collagenase activity (~28% collagen digestion) in the membrane fraction. The specific granule fraction contained latent MMP-8 that could be activated by APMA. The collagenase activity of a plasma membrane fraction combined with specific granules of neutrophils (54% digestion) was higher than the collagenase activity of the individual fractions (28% for plasma membrane, 1% for specific granules). These results are consistent with the notion that MT1-MMP may contribute to the activation of MMP-8 on the cell surface of peripheral blood neutrophils.
Genetic control of maternal mRNA degradation in the early Drosophila embryo

The maternal mRNA degradation pathway acts in the early 'Drosophila ' embryo to eliminate a subset of transcripts. This maternal pathway begins to function at or shortly after egg activation. Here it is shown that the wild-type activity of four maternal-effect loci, 'png', ' plu, gnu', and 'temp' are involved in the positive regulation of maternal mRNA degradation in the early embryo of 'Drosophila melanogaster'. 'png, plu, gnu', and 'temp' also result in defects in the regulation of the S-M (DNA replication-Mitosis) transition at the end of meiosis and various processes which are known to occur during egg activation and early embryogenesis. My results suggest that maternal mRNA degradation may be associated with, and regulated, by the molecular genetic events which are known to occur during egg activation and early development.
Image analysis and image reconstruction improvements in th determination of protein three-dimensional structures by electron microscopy

Image analysis and image reconstruction processes are critical in obtaining protein three-dimensional structures after their two-dimensional images are acquired by electron microscopy. This thesis reports my work on improving several aspects in this field. The angular distribution dependent (ADD) filtering algorithm is developed for an improved accuracy in three-dimensional reconstruction by the filtered backprojection method. The phase difference analysis (PDA) is employed to enhance the peaks in the sinogram correlation functions for a more accurate determination of projection directions for the randomly orientated protein particles. These improvements will result in a higher achievable resolution in determining protein structures by electron microscopy. A "shape factor" is defined for an investigation of automated molecular segmentation from electron micrographs and the potential feasibility has been shown. A novel three-dimensional reconstruction method, the finer voxel method, is proposed, and a theoretical discussion suggests that, with this approach, atomic resolution is potentially obtainable.
Maternal occupational exposure to organic solvents during pregnancy and subsequent visual and cognitive development in the child, a prospective controlled pilot study

This prospective study evaluated the effects of prenatal exposure to organic solvents (OS) on visual and cognitive functioning. Children (n = 33) whose mothers worked with OS during pregnancy were matched with a referent group (n = 28) on age, gender, ethnicity, maternal education, and socioeconomic status. Groups were compared on psychological tasks and measures of colour vision and visual acuity. Workplace exposure was assessed by interviews at time of initial contact during pregnancy. Prenatal solvent exposure was associated with significant group differences on expressive language (p < 0.01) and graphomotor ability (p < 0.05) adjusted for covariates. Visual test findings revealed significantly more deficits in blue-yellow (p < 0.01) and red (p < 0.05) colour discrimination, as well as poorer visual acuity (p < 0.05) among solvent exposed children. Frequency of colour vision loss in the exposed group was greater than the expected rate in the general population. The findings suggest that prenatal exposure to OS is associated with subsequent functional changes to neurodevelopment.
Morphological studies of polymer blends by scanning tunneling microscopy, phase separation in poly(methyl methacrylate)/poly(styrene- co-methylmethacrylate) systems

In this work, a new approach based on the scanning tunneling microscopy (STM) technique was developed to study the morphology of the phases in immiscible polymer blends. The mild operating conditions of the STM allow one to image samples that decompose under electron beam in the electron microscope. Blends of PMMA/poly(Stx-'co'-MMA) with different compositions of copolymer in the blend ([straight phi]), and styrene in the copolymer (x), were studied. Microtomed surfaces of the samples were made conductive by gold coating. The resolution of the STM technique in this approach is limited to the size of the gold grains (20 nm). Good STM images were obtained for all of the opaque samples, some of which were impossible to image with the electron microscope. Samples with x = 0.8 showed cocontinuous morphology for 0.3 < [straight phi] < 0.50, dispersed phase morphology for [straight phi] < 0.2 and [straight phi] > 0.6, and percolation limits at [straight phi] = 0.2 and [straight phi] = 0.6. The average size of the dispersed phase for [straight phi] = 0.8 and [straight phi] = 0.9 was found to be 520 nm and 340 nm for x = 0.8, and 170 nm and 150 nm for x = 0.50, respectively. In another approach, samples of 200 nm thickness were imaged by the scanning electron microscopy (SEM) after enhancement of phase contrast by means of electron beam which decomposed the PMMA phase. This approach gave good results only for the samples with overall styrene contents of more than 40%. The turbidity of the samples was found to be clearly correlated with the sizes of the features of the separated phases.
Storage conditions of avulsed teeth affect the phenotype of cultured human periodontal ligament cells

Immmohistochemical staining of markers expressed by osteogenic cells and fibroblasts were examined. Extracted human premolar teeth stored in air ("dry") or Ã-MEM ("wet") for 30 or 120 minutes as conditions for extra-alveolar tooth storage following avulsion. For type XII collagen, wet samples exhibited perinuclear staining while 30 minutes dry samples showed isolated foci. Staining for 120 minutes dry samples was weak and non-specific. Ã-smooth muscle actin was prominent in stress fibres in dry samples. Staining for osteopontin was perinuclear but more intense in dry samples. The focal adhesion pattern of osteopontin in 120 minutes dry samples resembled dud of migrating osteogenic cells. Pattern of staining did not vary for type III collagen or alkaline phosphatase, but was more intense in dry samples. Prolonged extra-alveolar dry storage favours increased ' in vitro' growth of cells expressing osteogenic cell markers while storage in wet favours growth of cells with the PL fibroblast phenotype.
Snare specific antibodies reveal distinct patterns of snare expression in the mammalian brain

Neuronal populations of the mammalian central nervous system display variations in the rate of neurotransmitter release. The SNARE hypothesis proposes that synaptic vesicle release is mediated through the formation of a protein complex composed of syntaxin, SNAP-25, and VAMP. In this thesis I hypothesize that SNARE isoforms are differentially expressed or post-translationally modified within neuronal populations of the central nervous system. The distribution of these proteins may correspond with variations in neurotransmitter release. A SNAP-25 monoclonal antibody was received which was thought to recognize a post-translational modification on SNAP-25. By characterizing this antibody, I localized the epitope to 140 residues within the N-terminus of SNAP-25, and determined that it did not include a phosphate group added by PKC or palmitoylation of four internal cysteine residues. During this investigation, poylclonal antibodies that specifically recognize SNAP-25, syntaxin 2, and syntaxin 3 were generated and, in conjunction with antibodies for syntaxins 1, syntaxin 4, SNAP-25, SNAP-23, VAMPs 1-3, and synaptophysin, were characterized in rat brain. It was found that these SNAREs are differentially distributed in regions of the hippocampus and cerebellum. The distribution of syntaxin 4 was both distinct and overlapping with syntaxin 1 in regions of presynaptic terminals. SNAP-23 and syntaxin 3 expression was uniform throughout the brain, with distinct expression surrounding neuronal bodies.
Differential regulation of matrix metalloproteinase-2 (MMP-2) by phorbol myrisate acetate, and by DL-Ã-difluoromethylornithine, in cell lines of varying tumorigenic and metastatic potential

The matrix metalloproteinases (MMPs) are thought to play key roles in tumor formation and malignant progression. The present study demonstrates novel alterations in the regulation of matrix metalloproteinase-2 (MMP-2) expression in cells of varying tumorigenic and metastatic potential. No change in MMP-2 gelatinolytic activity in response to PMA occurred in any of these cells. PMA did affect MMP-2 message expression in three of the four cell lines studied. Protein kinase C (PKC) mediated events were also found to play a role(s) in the regulation of MMP-2 message expression. An involvement of cellular polyamine levels in PMA modulated expression of MMP-2 was also observed. DFMO treatment altered PMA mediated regulation of MMP-2 message expression, but not MMP-2 gelatinolytic activity. Interestingly, DFMO alone increased the basal expression of MMP-2 message in two of the cell lines. Alterations in MMP-2 message expression, by PMA or by DFMO, involved both transcriptional and post-transcriptional events.
The effects of matching criterion contamination on the Mantel-Haenszel procedure

Modern bias detection procedures search for differences in item performance between demographic groups after conditioning on an estimate of the ability intended to be measured by the test. The estimate of ability is typically some function of the total test score. Since examinees with equal test scores are said to be matched on ability, the internal measure of ability is referred to as the matching criterion. When the test contains one or more biased items, the test score will not be a valid measure of ability. As a result, the matching criterion is said to be contaminated by the biased items. This study consists of a comprehensive examination of the Mantel-Haenszel (MH) procedure in the presence of a contaminated matching criterion. This examination focused on two primary issues: (1) assessing the effects of contamination on the MH procedure, and (2) developing alternative DIF detection procedures which are robust to contamination. The results indicate that the presence of contamination has minor effects on the MH procedure when contamination is small or moderate, but has substantial effects when contamination is large. The effects were related to the proportion of items containing contamination, and increased as the level of DIF in the contaminated items increased. Two solutions to the problem of matching criterion contamination solutions were proposed. First, a procedure was developed that adjusts the obtained MH value to correct for the effects of contamination. The results of a simulation study suggest that the adjustment is effective in general at correcting for the effects of contamination, losing efficiency only under the most severe levels of contamination and the smaller sample size ('N' = 250). A second solution to the problem of contamination was the proposal of ' MB-DIF', a new statistic that is theoretically robust to the effects of contamination. The results of a simulation study indicate that the performance of 'MB-DIF' exceeds that of the MH adjustment, particularly when sample sizes were large ('N' = 1000). Under the condition of large sample sizes, 'MB-DIF' was completely robust to the effects of contamination, maintaining power and Type I error rates identical to control conditions in which no contamination existed. The performance of ' MB-DIF' suffered slightly when sample sizes were small ('N ' = 250), largely due to inflated Type I error rates under large levels of contamination. The findings have two implications. First, bias detection analyses should consider the possible magnitude of bias in other items in the test when investigating the magnitude of bias in any given item. Second, adjustment procedures can control for the majority of the underestimation in DIF statistics when the matching criterion is contaminated. It appears that 'MB-DIF' offers a more effective solution to the problem of matching criterion contamination than adjusting the MH value.
The utility of behaviour in macroevolutionary studies, analyses of caddisfly (Trichoptera) case building behaviour

Behavioural data have been largely ignored in macroevolutionary studies since the advent of modern phylogenetic systematics. The main purpose of this thesis is to contribute toward the revival of behavioural data for macroevolutionary studies. I recognize four hinderances to the use of behavioural data. First, there is debate about what constitutes appropriate behavioural characters and behavioural units. Second, there remains concern about behavioural homology, lability and practicality. Third, potential applications of behavioural data are not fully appreciated; and fourth, sharing and exchanging behavioural information is limited due to the lack of an adequate forum. I address each of these issues to various degrees, concentrating on the first and third. I believe that the key to reviving behavioural data in systematics is selecting the most applicable behavioural units. Locomotory components of behaviour (i.e., how an animal behaves) are the most applicable for determining genealogical relationships and thus should be the primary source of behavioural data for macroevolutionary studies. In this thesis I detail caddisfly case building and use this information to undertake three different macroevolutionary endeavours: phylogeny reconstruction, assessment of behavioural evolution, and examination of broader macroevolutionary issues. I reconstruct four phylogenies within the Trichoptera using behavioural data: a subordinal-level analysis, a family-level analysis and two generic-level analyses. These analyses indicate that a complex behaviour shared by a group of organisms is likely to yield information about genealogical relationships, regardless of the relationship among the taxa or whether behavioural end-products appear markedly different. Using the behavioural information and a well-resolved phylogeny of the basal trichopteran relationships, I discuss a hypothesis of the evolution of case building in caddisflies. Building behaviour is analogous to development is because it is a hierarchical process that produces an end-product. I used the details of case-building behaviour to address the issue of homoplasy and to test for congruence between behavioural and end-product information. The variety of questions addressed in this thesis, all using locomotory components of case building in caddisflies, indicates the potential for this type of data in macroevolutionary studies.
The prediction of accidents on digital networks, characteristics and issues related to the application of accident prediction models

Transportation planning models are used to estimate, as accurately as possible, future traffic patterns, peak periods, travel time, and various environmental or other related traffic flow by-products. Unfortunately, traffic safety is seldom, if ever, explicitly analyzed during the transportation planning process. The non-evaluation of safety is attributed to various factors, including the lack of available tools needed to estimate the number of accidents on digital networks or urban transportation networks. Thus, the primary objective of this work was to develop a series of models that would allow the estimation of traffic accidents on digital networks; that is, before a physical transportation facility is built or upgraded. The secondary objective consisted of describing all the issues surrounding their application on digital networks. To accomplish this goal, several accident prediction models that include trend were developed to predict accidents at nodes and on links. As part of this work, a new method to estimate the coefficients of models with trend is explained. A few illustrative applications of the models are also presented. The models were applied to three sample digital networks and the simulation of traffic was performed with either EMME/2 or Paramics. The results showed that it is possible to predict accidents on digital networks, but the accuracy is directly related to the precision of transportation planning software programs. Hence, inaccurate traffic flow prediction leads to incorrect accident prediction. Thus, efforts should be made in trying to find better flow estimates. Some proposed models are also sensitive to how the digital network is coded and the predicted number of accidents should be adjusted accordingly. Finally, several issues and limitations related to the application of accident prediction models to determine the safest paths on digital networks and evaluate the safety effects of dynamic route guidance systems are described in this thesis.