VictorJuiz/thesis huggingface dataset:
Jesus and the Maya, the Inter-Church Committee on Human Rights in Latin America and the indigenous peoples of central America and southern Mexico

This thesis examines the work of one ecumenical human rights organization, the Inter-Church Committee on Human Rights in Latin America, in the area of the Americas traditionally occupied by the indigenous Maya, the mountains and plains of northern Central America and the southern territory of Mexico. The organization's work is studied in relation to the context of the wars, systemic, cultural, and militaristic, being waged against the people, the Maya, by the states of the region. The further concentration of wealth and power, the outbreak of new civil wars, and the appearance of cultural critiques of inequality rather than purely historical ones over the last decades, have resulted in the astounding growth of peoples' movements for real democracy in the Americas. Nowhere have these trends been more pronounced than Latin America. This thesis examines these occurrences and their significance for some of the original inhabitants of our lands, the Maya.
On being homeless, women's sense of connection

A study of homeless women was conducted to explore their sense of connection to important others. Connections to others are viewed as central to women's self concept and psychological maturation (Miller, 1976). Because homeless women often exist in isolation, their ability to achieve this developmental goal may be impeded. A feminist mode of inquiry informed the study. Thematic analysis of semi-structured interviews with seven homeless women yielded themes in two domains: how relationships unfold and the meaning of being without a home. Themes within the first domain included Disconnection--lack of important relationships, impermanence, inauthenticity and superficiality, difficulty trusting others, stress of other's problems, and connection to professional supports. Second domain themes were violence, vulnerability, hypervigilance, lack of space and privacy, loss of control and independence, distress, and positive perspectives. The study highlights the common experiences of disconnection of homeless women and provides further understanding of the importance of relationships.
Intramolecular Diels-Alder reactions of alkenylboranes & a hetero Diels-Alder approach to the total synthesis of Martinelline

This thesis is a summary of research conducted since September 1995. It is comprised of two distinct projects and contains three chapters: Introduction, Results and Discussion, and Experimental. In the first project, intramolecular Diels-Alder reactions of alkenylboranes were investigated. A one-pot three sequence transformation which involved: (i) hydroboration of a dienyne with dicyclohexylborane, (ii) thermal intramolecular Diels-Alder reaction in benzene, containing 5 mol % of butylated hydroxytoluene, and (iii) subsequent oxidation by $\rm Me\sb3NO{\cdot}H\sb2O$ to an alcohol, was optimized. All three substrates that were tested successfully underwent the cycloaddition in moderate to good yield. In each case, a single diastereomer corresponding to endo-addition, was formed. The second project was concerned with a hetero Diels-Alder approach to the total synthesis of Martinelline. A three component coupling strategy was devised to construct the pyrroloquinoline core of this natural product in a single step. In the presence of catalytic dysprosium (III) triflate, N-acylated 2-pyrrolines, acting as dienophiles, underwent cycloaddition with 2-azadienes formed in situ from the condensation of substituted anilines and benzaldehyde. Excellent yields were obtained, but poor diastereoselectivity was observed. Deprotection of these adducts is also reported. In the absence of benzaldehyde, the aniline and two equivalents of a 2-pyrroline under these conditions formed a cycloadduct as a single diastereomer in good to excellent yield. NMR data suggested that the diastereomer was the product of endo-addition. A comparison of these data with those reported in the first isolation of Martinelline, indicates that the relative stereochemistry of the adduct is not the same.
A recognition of being, exploring native female identity

This thesis explores the subject of Native female identity through interviews with twelve Native women in the Toronto area. The intent is to present a positive vision of Native womanhood in response to all the negative images that have plagued Native female identity since contact with the Europeans. To build this vision, the author sought out exemplary Native women and explored the following questions with them: How have Native women resisted negative definitions of identity? How have they constructed positive alternatives? What is the understanding of Native womanhood that emerges? and How does this influence the conduct of Native women in their communities? Traditions of gender equity in Native societies, and strategies of resistance to racist and sexist definitions of Native womanhood are presented as part of a literature review. The author approaches the work from a personal standpoint; that of a Native woman seeking information about her identity.
Quantitative magnetic resonance imaging of ultrasound acoustic fields

This thesis presents the first demonstration of the use of phase-contrast magnetic resonance imaging to detect the nanometer scale motions resulting from medical ultrasound. It provides a new, non-invasive means to visualize and measure ultrasound fields in real tissue. The technique requires a large oscillating magnetic field gradient of $\sim$.5 T/m which oscillates at $\sim$1 MHz. The fundamental issues in MR visualization of ultrasound fields are outlined and the accuracy and sensitivity of the technique is demonstrated experimentally. Based on this apparatus, we show an ultrasound noise equivalent sensitivity of 3.9 nanometers displacement, 19 kilo Pascals pressure and 12 milliwatts intensity for a 515 kHz US field. On the basis of potential accuracy, we believe that it may become a new standard for ultrasound exposimetry and could provide an entirely new platform for the study of complex interactions of medical ultrasound with tissue.
Functional regulation of N-methyl-D-aspartate receptors by serine/threonine protein kinases

The N-methyl-D-aspartate (NMDA) subtype of glutamate receptor plays a crucial role in a variety of neuronal processes such as long-term potentiation (LTP). A major consequence of NMDA receptor activation is a large influx of calcium into the cell which in turn leads to the activation of protein kinases. Chen and Huang (1992) reported that PKC enhances NMDA currents by reducing the Mg$\sp{2+}$ sensitivity of these channels in trigeminal neurons. In the hippocampal neurons activation of PKC has been reported to enhance or reduce the NMDA activated currents (Wang et al., 1994, Markram and Segal 1992). In these experiments, we examined the effects of intracellular perfusion of PKCM (a constituitively active form of PKC) on NMDA-evoked currents in cultured and acutely isolated hippocampal neurons. Also the effects of Ca$\sp{2+}$/calmodulin dependent protein kinase II (CaMK II) on NMDA-evoked currents were examined. Results indicate that PKC acts via a phosphorylation-dependent mechanism to enhance NMDA-evoked currents in hippocampal neurons without altering the Mg$\sp{2+}$ sensitivity of the channels. (Abstract shortened by UMI.)
Narratives of living with diabetes, an examination of self, identity, and the body

This study examined the personal and social meanings of living with insulin-dependent diabetes mellitus through an integration of social theory with individuals' everyday experiences with diabetes. The theory of narrative, identity, self, and the body, was used to illuminate the continuous processes involved in being an individual with diabetes and to contextualize the challenges to managing diabetes. Transcripts of unstructured interviews previously conducted with four women who have diabetes were the basis for this study. Diabetes narratives were used to construct identities and selves and to interpret one's bodily experiences. The self as a cognitive, reflexive, subjective, and physical experience, identity as a temporal and relational construct influenced by others and one's own recognitions, and the body as a lived experience and as a product of cultural themes, provided the framework for a deeper understanding of the personal and social context in which the meaning of diabetes was constructed.
Effect of familiarity and feature differences on visual search

Q. Wang, P. Cavanagh and M. Green (1994) demonstrated a pop-out effect in searching an unfamiliar target among familiar distractors (U-F condition), and argued for the importance of familiarity difference between the target and distractors in determining the search efficiency. In Experiment 1a, we replicated this pop-out effect with targets and distractors which differed in low-level features. However, in Experiments 1b and 2, a pop-out effect was not uniformly obtained with targets and distractors which differed in line arrangement but not in their orientation. The results suggest that a U-F pop-out effect may be partially mediated by feature differences between targets and distractors. In Experiments 3 and 4, we used target-distractor pairs with feature differences controlled across F-F, U-F, F-U, and U-U conditions. We found that the familiarity of the distractors, instead of the familiarity difference between the target and distractors, contributed to efficient searches.
Telling stories, empowering lives, the role of personal narratives on female socialization at the elementary school level

Storytelling is essential; myths, legends and fairy tales give significance to our existence. Stories are also a primary tool of culture through which socialization occurs and a way in which children learn the societally defined scripts of adulthood. Children need stories, myths and fairy tales to help them interpret their own lives, and they need to resist patterns in known stories which reinforce and preserve adverse cultural stereotyping. This study explored how replacing existing fairy tales and established literature with the self-narrative storytelling process at the middle elementary school level might empower females to seek alternative definitions and find their own voices. Storytelling sessions with grade five female students attending an inner-city school were observed, first focusing on fairy tales and favourite existing stories and progressing to the sharing of personal stories based on life and experience. The ultimate aim was for each girl to create an empowering self-narrative.
Sequence diversity of the mitochondrial ATPase 6 gene in representative species of the genus Agaricus

The evolutionary relationship between three genetic elements (ATPase 6 gene, the plasmid pEM, and the pEM homologue) within the mitochondria of representatives of the genus, Agaricus, was evaluated. The origin of the plasmid and the mitochondrial homologue was examined. The mitochondrial-encoded ATPase subunit 6 of the Basidiomycete Agaricus bitorquis has been identified and sequenced in this study. The ATPase 6 gene consists of 828 bp and encodes a protein of 276 amino acids. Comparison of amino acid sequences between the A. bitorquis protein and four Ascomycete proteins showed high levels of similarity. The structural similarities within the ATPase 6 proteins is indicative of functional conservation and common ancestry. Approximately 550 bp within the gene was determined for nine species of Agaricus and a closely related species, Leucoagaricus sp. The results suggest a high degree interspecific variation. A partial intraspecific survey of A. bisporus revealed a low degree of intraspecific variation; a single base substitution distinguished two of the six isolates. An Agaricus phylogeny was constructed based on sequence variation of the ATPase 6 gene, and this phylogeny was compared with the pEM phylogeny. The comparisons illustrated different topologies which imply a different evolutionary history.
Self-esteem among university students with and without physical disabilities

Self-esteem among 64 full time, undergraduate university students with and without physical disabilities was investigated. The participants completed Harter's Self-Perception Profile for College Students, a measure of self-esteem, a personal questionnaire to determine their level of independence and a personal interview to determine their attitude towards having a physical disability. Students with and without physical disabilities had similar levels of global self-esteem, although those with a physical disability had lower self-esteem in the area of romantic relationships. The study also indicated that female students with physical disabilities had higher levels of self-esteem in the areas of social acceptance, morality and appearance and students with physical disabilities living at home considered close friendships to be less important and job competence to be more important than those not living at home.
Characterization of a neural-specific inducible genetic system in transgenic mice

This paper describes an attempt to utilize a recently developed system based upon prokaryotic control elements, the tetracycline transactivator system, to direct inducible expression of reporter gene sequences specifically in the nervous system of transgenic mice. The transactivator protein, tTA was placed under the control of the human neurofilament light chain gene promoter (pNFL) to give neural-specific expression. Although tTA mRNA expression was detectable by reverse transcriptase-polymerase chain reaction in the brains of pNFL-tTA transgenic mice, no reporter gene expression was observed when these mice were crossed to tet-O-$\beta$galactosidase transgenics. The most likely explanation for the lack of function is that the pNFL-tTA transgene sequences integrated into regions of the genome where proper transgene expression was prevented. Recent experiments from other laboratories have also suggested that an optimal level of tTA expression must be attained for proper functioning of the system. This is most conveniently done by choosing an appropriate promoter to drive tTA. It is possible that the human NFL promoter does not give this optimal level of tTA expression. Our laboratory is currently utilizing other neural-specific promoters to enable function of the tetracycline inducible system in neural tissue of transgenic mice. (Abstract shortened by UMI.)
An analysis of the in vivo SEB response in a T cell receptor scid transgenic mouse

The superantigen SEB was used to analyze the immune response of a C.B-17 scid mouse carrying a transgenic T cell receptor expressing V$\alpha$ 13 and V$\beta$ 8.2. There are no B cells present in this mouse and the only T cells present express the T cell receptor transgene. Therefore the response of a clonotypic population of T cells can be studied in the absence of all other T or B cells. The splenic T cells from these mice mounted a response to SEB in vivo, illustrating that a clonotypic population of T cells is able to mount an SEB induced immune response in the absence of other T cells or B cells. IL-2 R $\alpha$ staining suggested that a majority of the T cells had been activated in response to SEB. In addition upon SEB injection a population of CD4- TCR+ cells was detected in the spleens of SEB injected transgenic scid mice. A similar population was seen in the thymus but not in the spleen of control mice.
Real-time computed torque control of flexible-joint robots

Evergrowing demand for speed, accuracy and higher payload capacity of industrial robots has led to redefining the robot control problem. As speed and accuracy are always at loggerheads, achieving one without compromising on the other, calls for a closer examination of the physical system of the robot, to devise sophisticated control techniques that would meet the rigorous specifications. This thesis aims at modelling the dynamics of a typical industrial robot, incorporating the flexibility effects due to the mechanical compliance of the joints. Using a reduced order model of the flexible-joint system, the computed torque control method is implemented on the robot, in order to evaluate the real-time trajectory tracking performance of the computed torque controller, compared to the PID-based commercial controller of the robot. Issues related to real-time multi-axis servo control, dynamics modelling and analysis, parallel processing, electro-mechanical systems design and integration, are addressed in this thesis.
The energetics and dynamics of surface sealing, a laboratory investigation

Understanding the controls on the components of the hydrologic cycle is important for maintaining environmental quality since soil plays an important role in the hydrologic cycle by influencing the timing of and the path taken by water once it reaches the land surface. Surface seals formed under rainfall have been recognised to occur on soils from all over the world and are known to reduce infiltration and increase surface runoff; however, measurements of hydraulic conductivity during a rainfall event have not been possible. Calculations of hydraulic conductivity require measurements of soil water content and soil water potential. Consequently, this thesis involves the design of systems to measure these variables at the appropriate time and length scales. Column experiments using a silt loam from southern Ontario were conducted to examine how two previously identified controls upon surface sealing; antecedent moisture conditions and rainfall characteristics, affect the soil hydraulic conductivity. Even at very small length scales, of the order millimetres, textural variations were evident from the soil water content-time plots. Thus, even at very small length scales it seems inappropriate to assume a uniform soil water content. The temporal changes in the hydraulic conductivity were found to be an exponential function of changes in the soil water potential. The relationship between the final hydraulic conductivity and the applied rainfall varied with initial soil water content. At lower rainfall intensities a smooth hydraulic conductivity-soil water potential was observed that was unaffected by the initial soil water content. However, this relationship was disrupted towards the end of the higher intensity rainfall events due to disruption of the soil structure. A van Genuchten model (van Genuchten, 1980) could be fitted with a high degree of accuracy to the measured soil water content-soil water potential data. When the parameters of the fitted curve were used to model the unsaturated hydraulic conductivity function, the fit between this function and the measured hydraulic conductivity values was extremely poor.
The influence of low atmospheric CO¦2 on temperature stress in Phaseolus vulgaris: Implications for Pleistocene environments

Atmospheric CO$\sb2$ levels for the last global glaciation and during most of the Pleistocene were 30-50% lower than at present. This thesis addresses some of the physiological consequences of Pleistocene CO$\sb2$-levels for C$\sb3$-plant growth by exploring CO$\sb2$ x stress interactions. Growth chamber experiments were conducted to determine the effects of low CO$\sb2$ (200 $\mu$bar) on temperature stress (35$\sp\circ$C) in Phaseolus vulgaris. Plant dry weight decreased by 64% in plants grown at low CO$\sb2$/35$\sp\circ$C relative to ambient CO$\sb2$/35$\sp\circ$C. Decreases in plant biomass were largely the result of a 60% reduction in assimilatory surface area (200$\mu$bar/35$\sp\circ$C vs. 380$\mu$bar/35$\sp\circ$C). Photosynthesis decreased by 42%, while leaf respiration increased by 90% for plants grown at 200$\mu$bar/35$\sp\circ$C relative to 380$\mu$bar/35$\sp\circ$C. Reduced plant size under low CO$\sb2$ and elevated temperature was not correlated with enhanced carbohydrate deficiency because total non-structural carbohydrates at 200$\mu$bar/35$\sp\circ$C was less than 20% different than at 200$\mu$bar/25$\sp\circ$C.
Impact of fertilization and vegetation management on growth and nutrition of white spruce seedlings and related soil nitrogen transformations

Outplanting performance of white spruce seedlings (Picea glauca (Moench) Voss) was studied under two silvicultural treatments (nitrogen fertilization and vegetation management) for one growing season, on an old agricultural field in Southern Ontario. Nutrient loading increased seedling survival after one growing season in the field. The increased survival amounted to an accumulation of 52% more biomass and 54% more N content as compared to conventionally raised seedlings (1N) in a greenhouse. Post planting N fertilization alone neither improved seedling survival nor total biomass. However, weed control using a herbicide increased total plant N uptake by 20% compared to seedlings grown on weedy plots. These results indicate that the greater N uptake was due to increased availability of nitrogen caused by either weed removal or by increased nitrification as a result of herbicide treatment. Nitrification was accelerated after herbicide and fertilizer application. Available NO$\sb{3\sp-}$-N was positively correlated with the total plant N uptake (r = 0.81). Accelerated nitrification as a result of herbicide use suggests that it affected soil microbes, particularly those responsible for nitrification process. However, a laboratory investigation showed that herbicides and their rates had no effect on nitrification. Under field conditions, variation in herbicide use, application rate significantly altered nitrification. The differential effect of herbicide use between laboratory and field conditions suggested that the increase in nitrification was due to the removal of weeds, reducing their N uptake from soil in the field.
Carbon cycling in the microbial mats and bottom accumulations of selected lakes of the Cariboo Plateau, isotopic constraints and implications for interpretation of the geologic record

Highly calcified cyanobacterial mats are observed in the lakes of the Cariboo Plateau, British Columbia. Varying levels of methane production occur in the sediments of four of the lakes resulting in surface water methane levels of 0.06 to 9 $\mu$M. Up to 99% of methane produced in the sediments of these lakes is oxidized at the oxic/anoxic transition. In certain lakes, anaerobic oxidation of methane is a significant process below the oxic/anoxic transition. Zones of anaerobic methane oxidation are spatially correlated with zones of sulphate reduction as is observed in marine sediments. Anaerobic methane oxidation does not impact the determination of isotopic discriminations calculated for the four mats communities. Discriminations are significantly higher than those observed in modern organic rich mats but, very similar to those determined for Precambrian stromatolites. The high levels of calcification of the Cariboo Lakes mats (70 to 92% carbonate dry weight) reduce carbon demand, result in more rapid transport of carbon dioxide to the cells and may account for the expression of large isotopic discriminations observed. The occurrence of such large discriminations in modern systems has significant implications to the interpretation of the geologic record.