VictorJuiz/thesis huggingface dataset:
Mutational analysis of residues involved in substrate binding and catalysis of E. coli argininosuccinate synthetase

E. coli argininosuccinate synthetase (EAS) catalyzes the reversible ATP dependent ligation of citrulline and aspartate to form argininosuccinate, AMP, and inorganic pyrophosphate. The structure of the EAS with and without its substrates has been solved. To determine the role various residues play in substrate binding and catalysis, site directed mutagenesis of thirteen residues in the active site has been performed. A radioactive assay has been developed and the Km of wild type-EAS for aspartate, ATP, and citrulline determined to be 71 ± 10, 237 ± 38, and 107.1 ± 12 μM, respectively. The corresponding Vmax values are: 2.9 ± 0.1, 3.3 ± 0.2, and 1.4 ± 0.1 μmol·min −1·mg−1. The kinetic results confirm the role of Q46, Y98, T130, K132, R138, S191, D193, T200, E202, and E207 in substrate binding and suggest that R106 and D135 are involved in catalysis. The available EAS and Thermus thermophilus AS structures confirm that the kinetic and structural data are in good agreement with one another.
The early external cephalic version (ECV) trial: a randomised controlled trial of ECV beginning at between 34-36 weeks compared to 37-38 weeks gestation

Background. In about 3–4% of all pregnancies at term the fetal presentation is non-cephalic. External cephalic version (ECV) at term has been shown to decrease the rate of non-cephalic presentation at birth, and to decrease the rate of Caesarean section (CS). However success rates for ECV are low. This randomised trial was done to compare the effectiveness of a policy of beginning ECV early at between 34–36 weeks gestation, and beginning ECV at 37–38 weeks gestation. Methods. At 25 centers in seven countries, 233 women with a singleton breech fetus were randomly assigned to having ECV performed early at between 34–36 weeks, or delayed until 37–38 weeks. The primary outcome was the rate of non-cephalic presentation at birth. An intention to treat analysis was used. Findings. Data were received for 232 women, with 116 women in each of the early and delayed ECV groups. The rate of non-cephalic presentation at birth in the early ECV group was 66/116 (56.9%) and 77/116 (66.4%) in the delayed ECV group (RR [95% CI] = 0.86 [0.70, 1.05], p = 0.09). The rate of serious fetal complications and the rate of preterm birth <37 weeks were not significantly increased in the early ECV group compared to the delayed ECV group (6.9% vs. 7.8% RR [95%CI] = 0.89 [0.36, 2.22] p = 0.69 versus 8.6% vs. 6.1% RR[95%CI] = 1.42 [0.56, 3.59] p = 0.31). The rate of CS was 75/116 (64.7%) compared with 83/116 (71.6%) in the early and delayed ECV group respectively (RR [95% CI] = 0.90 [0.76,1.08] p = 0.32). Neonatal outcomes were comparable in the two groups. In both groups, the rate of reversion to non-cephalic presentation was low and the majority of women indicated that they would consider having an ECV in another pregnancy. Interpretation. Early ECV may reduce the incidence of non-cephalic presentation at delivery. A large pragmatic trial is required to assess this approach further in terms of CS rates and neonatal outcomes prior to recommending changes in clinical practice. In the interim, women with breech fetuses should be provided with information about ECV that includes the findings and limitations of this trial.
The incidence of prenatal alcohol exposure in Montevideo, Uruguay as determined by meconium analysis

Prenatal alcohol exposure in developing countries has largely been overlooked despite knowing that exposure can lead to fetal alcohol syndrome. This study characterises the incidence of prenatal alcohol exposure in Montevideo, Uruguay using a novel biomarker, fatty acid ethyl esters (FAEE) in meconium. Nine hundred and five meconium samples were collected from 2 public hospitals over 2 months from a population of low socioeconomic status. Forty-four percent were above the positive cut-off and represent those newborns with risky prenatal exposure during the final two trimesters of pregnancy. Infants with prenatal alcohol exposure were more likely to have prenatal exposure to tobacco (RR 1.56, 95% CI 1.11-2.20) or any illicit drug (RR 2.29, 95% CI 0.98-5.31). Ethyl linolate was a significant predictor of infant birth weight along with prenatal tobacco exposure, maternal BMI, and infant gender. Education for women of childbearing age concerning prenatal alcohol exposure is needed in Uruguay and other developing countries.
The badge and the baccalaureate: an analysis of attitudes and beliefs associated with policing and higher education in Ontario, from a management perspective

This study utilized a cross-sectional, dual data collection methodology to solicit police management (command and senior officers') attitudes and beliefs towards five distinct vectors or quadrants associated with policing and higher education (Expectations, Relevance, Financial Rewards, Promotions and Resources). A quantitative e-mail survey, employing a 5-point Likert scale and an optional qualitative follow-up semi-structured interview method of inquiry were employed. The multistage data collection process utilized a combination of both probability and non-probability sampling techniques. Surveys ( n=100) were distributed to command senior officers within the five participating Greater Toronto Area police services—The Toronto Police Service, the Durham Regional Police Service, York Regional Police Service, Peel Regional Police Service and the Ontario Provincial Police. From the 82 survey respondents, 24 were interviewed. The survey and follow-up interview sought specifically to answer three research questions, associated to the aforementioned 5 Vectors. In addition three hypotheses arising from the five independent variables and the twenty-seven dependent survey items were also cross tabulated. Findings indicate that command and senior officers modally believe that, the current minimum entry level educational standard should not be raised, that some level of higher education is necessary to meet the future needs of policing, educational attainment and wages should not be linked and that current financial support for members pursing higher education is sufficient. It was also observed that police management felt that, promotions should not be linked to educational attainment; all command officers should have a minimum baccalaureate degree, it is too costly to fully subsidize higher education for all members, and that other expenditures take priority over funding higher education. Emerging from the study was also evidence of significant disparity in educational benefit policy across jurisdictions. Command and senior officers were surprisingly unaware of the magnitude of such disparity and its ramifications. An additional outgrowth of this research was to highlight the premium value placed upon pre-hire military experience by police management. (PsycINFO Database Record (c) 2016 APA, all rights reserved)
The impact of bupropion on cue-reactivity and the subjective effects of smoking in ad-lib smokers

Bupropion is a first-line pharmacotherapy for smoking cessation, but its mechanisms of action are unclear. The effect of bupropion on the smokers' biased reactivity towards smoking-related cues and the influence of bupropion on the subjective effects of smoking were investigated. In a parallel, double-blind study, bupropion (300mg/day) or placebo was randomly assigned for six weeks to 32 daily smokers who did not intend to quit. Outcome measures were collected in biweekly experimental sessions and daily in a diary, under ad-lib smoking condition. Bupropion did not selectively attenuate reactivity towards smoking-related words or visual cues, nor did it influence the subjective effects of smoking. Bupropion-treated subjects showed a reduction in serum cotinine from pre to post treatment, but reported no change in the number of cigarettes smoked daily. These findings do not support reduction in cue-reactivity or attenuation of the subjective effects of smoking as potential mechanisms of action of bupropion.
Structurally heterogeneous OLAP dimensions

In OLAP warehouses, data consists of facts modeled as points in multidimensional spaces. Dimensions themselves have structure, represented by a directed graph of categories, called hierarchy schema, a set of members for each category, and a child/parent relation between members. Some facts may be the result of cube views, which are queries that aggregate raw facts to more coarse-grained spaces defined by categories taken from sets of dimensions. A powerful technique in OLAP data processing, known as aggregate navigation, is to find queries that derive the cube views from other precomputed cube views. Such queries are inferred from the hierarchy schemas involved. This inference process, however, works under a strong assumption on the regularity of the data. In particular, it does not account for structural heterogeneity, a phenomenon that arises when several dimensions representing the same conceptual entity, but with different categories, are mixed into a single dimension. In this thesis we propose a natural extension of OLAP data modeling and aggregate navigation to deal with structural heterogeneity. In our approach, cube views are extended to cope with heterogeneous dimensions. A novel class of integrity constraints, dimension constraints, that enriches the semantics of hierarchy schemas, is proposed to capture heterogeneity and to support the inference task in aggregate navigation. The modeling of heterogeneity provides significant flexibility for representing dimensions, a property not encountered in traditional models for homogeneous dimensions. We investigate this feature in our model and study the problem of restructuring dimension schemas. We present a series of results that give conceptual insight into the problem, which include a notion of dimension schema equivalence, algorithms for testing it, and a sound and complete set of transformations for the structural manipulation of dimension schemas.
Belonging through participation: an exploration of the Caribana, Pride, and Santa Claus parades in Toronto, 1998-2004

This exploratory, qualitative study is anchored in the critical research tradition. It examines three celebratory street parades in Toronto: the Caribana, Pride, and Santa Claus parades within a seven year time period. By considering these parades as informal sites of education, it attempts to address a set of research questions that seeks to understand the role and contribution of these parades to the socio-cultural aspects of parade participants' citizenship. The questions are framed within a problem that sees the lack of a sense of belonging as an impediment, among others, to the realization of full citizenship for 'visible minority' citizens in Canada. Triangulated in data collection methods and aided by visual data, this study finds that each of the parades commands its own ethno-cultural constituency. By providing a participatory space and various forms of utilities, these parades also enrich the socio-cultural dimensions of parade participants' citizenship, and as a result they enhance a sense of belonging for the communities associated with them. The researcher argues in favour of tangible public supports for cultural events such as parades, especially for the events that have marginal groups as their primary constituencies, as an effective means to address the problem of social exclusion. This study identifies five broad processes in the parades that contribute to parade participants' sense of belonging. It also identifies and critically examines the roles and contributions of fifteen major direct and indirect parade components which contribute to the creation of such a sense. In the tradition of critical pedagogy and cultural studies, these findings are expected to contribute to the nearly non-existent field of informal civic education involving ethno-cultural celebratory public events. The stakeholders associated with such events, educators, social justice activists, policy makers, artists, and producers of cultural festivities who wish to facilitate civic participation and social cohesion among people to enrich the socio-cultural dimensions of Canadian citizenship, may use the findings of this study as empowering knowledge in their tasks for designing, evaluating, managing, and improving the civic contributions of these events.
Investigation of a region of rabbit sodium/glucose cotransporter, (rSGLT1), that influences sodium interaction, empty carrier kinetics and turnover

Ion-coupled transport is a ubiquitous mechanism of solute movement across the plasma membrane. The rabbit Na+/glucose cotransporter, rSGLT1, translocates 1 glucose with 2 Na+. rSGLT1 is a well studied system of ion-coupled transport; it can be expressed in Xenopus laevis oocytes, and two-microelectrode voltage clamping can be applied. Steady state currents with sugar substrate provide affinity constants and turnover number; presteady state currents, in the absence of sugar, are useful to study empty carrier kinetics. Previously, cysteine scanning mutagenesis and chemical modification, revealed residues 163, 166 and 173, in the external loop joining TM's IV-V, form part of a Na+ interaction and voltage sensing domain. However, neutrality and negative charge at position 170 affects charge transfer, not Na+ binding. A full characterisation of the Q170 site was initiated, with neutrality (Q170C, Q170A) and negative charge (Na+ (2-sulfonatoethyl)methanethiosulfonate (MTSES) reacted Q170C, and Q170E). Many rS-GLT1 parameters are modulated with neutrality/negative charge at 170. The V0.5 value (voltage sensitivity) is shifted negatively with neutrality (Q170C V0.5 = -13.8 +/- 5.5 mV) and positively with negative charge (Q170E V0.5 = 21.7 +/- 1.4 mV), compared to wt. Q dep/Qmax value (conformational preference at -50 mV) showed that neutrality causes movement to inside facing conformation (Q170C = 78 +/- 4%), whereas negative charge causes movement to outside facing conformation (Q170E = 91 +/- 3%); wt = 86 +/- 2%. Transient currents analysis: two time constants ( tgr;fast, tgr;slow) for Q170E; three ( tgr;fast, tgr;medium, tgr; slow) for wt and Q170C; Q170E tgr;slow is twice as fast as tgr;slow's of wt and Q170C. Turnover number is reduced by neutrality (Q170C k = 11.2 +/- 1.7 s-1, n = 7, at -150 mV) and negative charge (Q170E k = 11.6 +/- 2.5 s-1, n = 4, at -150 mV), compared to wt (22.8 +/- 0.5 s-1); only negative charge altered sugar affinity (reduced by half) and Na+ affinity (increased 5-fold), compared to wt rSGLT1. Therefore, neutrality/negative charge at Q170 in rSGLT1 profoundly affects kinetics, including the outside/inside facing distribution of cotransporter, thereby influencing charge transfer and Na + interaction.
Urban space in South African literature: Johannesburg

The South African city presents a paradigm of imposed constricted space, yet it is a contradictory site of opportunities as well as exclusions and provides a way of exploring the way people engage with modernity, adopt new identities, and contest abstract space. This study looks at the representation of Johannesburg in South African fiction and autobiography of the last fifty years. It examines the way in which literature engages with and changes in response to four prominent phases in Johannesburg's formation and transformation: the slum locations; the erasure of the locations; the expansion of the townships; and the post-apartheid city. Chapter one examines the location in Peter Abraham's Tell Freedom and Es'kia Mphahlele's Down Second Avenue. These texts, as Bildungsromane, articulate the protagonist's emerging self-consciousness as he confronts the racialized city. A concomitant of the subsequent erasure of the locations and emergence of the townships is the decline of the Bildungsroman, a genre that focuses on interiority and on touring the city rather than seeing the city whole as in a map. Chapter two looks at the erasure of Sophiatown in Bloke Modisane's Blame Me on History and Marlene van Niekerk's Triomf. By invoking the uncanny to reveal the community erased by apartheid planning, these texts commemorate and challenge the destruction of Sophiatown and the attempt to build an Afrikaner suburb in its place. Chapter three considers the dual city of black townships and white suburbs as depicted by Miriam Tlali and Nadine Gordimer. Tlali's Between Two Worlds, which describes a microcosm of apartheid's divided spaces, provides an entry point to a discussion that turns on the intersections of the "contagious" and constrained body and bounded urban space. The final chapter considers the post-apartheid city in novels by Ivan Vladislavic, Phaswane Mpe, and Gordimer. The end of apartheid and a changing city herald new ways of ordering urban space and of seeing the city as part of the world rather than as a part of the nation. The city is seen as a site contending with the contradictory claims of globalism and Africanization, homogeneity and heterogeneity, deterritorialization and place-centredness.
The effect of temperature on sorption, biodegradation, and transport of monochlorobenzene in soil

The effect of temperature on the sorption, biodegradation, and transport of monochlorobenzene (MCB) in soil was investigated through batch sorption, microcosm and column tests conducted under aerobic and abiotic conditions. The Freundlich distribution coefficients and retardation values estimated for a sandy soil with moderate organic content decreased over 40% from 22°C to 55°C under equilibrium sorption conditions. However, this effect was not observed in subsequent column tests where rate-limited conditions dominated. An aerobic consortium cultivated from aerobic sludge was enriched on MCB. Degradation rates evaluated from microcosm and column studies operating at 22°C and O2 rich conditions indicated a half-life for MCB around 1 to 2 hours. Degradation rates were significantly reduced from 1.04hr -1 at 22°C to 0.03hr-1 at 55°C as demonstrated in both microcosm and column studies. The results of this investigation indicate thermally enhanced bioremediation will inhibit MCB degradation and thus should not be applied for MCB remediation.
The effects of vitamin D on the spontaneous and menisectomized guinea pig models of osteoarthritis

Osteoarthritis is characterized by degeneration of cartilage and subchondral bone. The Framingham study showed that low serum levels of 25(OH)D may be associated with increased osteoarthritis progression. We examined the effects of a vitamin D (0IU/day, 153IU/day, 513IU/day) on the progression of osteoarthritis in the spontaneous and menisectomized guinea pig models; 1, 3 and 6 months post menisectomy. Both cartilage (Mankin-grading, tidemark) and bone (osteophytes, subchondral thickness, mineral, histological and structural properties) were investigated. Vitamin D dosing was effective at raising the 25(OH)D levels, without negative side-effects. In the spontaneous guinea pig model, vitamin D caused no changes in the cartilage degeneration, vitamin D deficiency compromised bone quality, while pharmacologic doses maintained bone quality. Minimal changes were seen in the bone and cartilage quality for the increased vitamin D diet in the menisectomized guinea pig model. The vitamin D deficient diet produced deterioration in bone and cartilage quality.
Elucidating the biological role and regulation of conserved actin cytoskeleton proteins in the budding yeast Saccharomyces cerevisiae

The function of the actin cytoskeleton in the budding yeast, Saccharomyces cerevisiae depends on the ability of a network of actin filaments and other proteins to change dynamically in response to intra and extra-cellular cues. Actin-binding proteins and regulatory proteins interact and function together to regulate the assembly and disassembly of the actin filaments. The specific activity and biological function of many of these actin-associated proteins remains unclear. In this doctoral work, I have sought to uncover the biological role and regulation of several conserved actin cytoskeleton proteins: coronin (Crn1), the Arp2/3 complex and the yeast amphiphysins (Rvs161 and Rvs167). I report on a novel mode of Arp2/3 complex regulation mediated by the highly conserved actin binding protein coronin. I show that yeast coronin (Crn1) physically associates with the Arp2/3 complex and inhibits WA- and Abp1-activated actin nucleation in vitro. I also report on a possible role for phosphorylation in regulating the activity of Crn1 in vivo. I show evidence that Crn1 is a substrate for Pcl-Pho85 in vitro and that Pho85 regulates the interaction between Cm1 and the Arp2/3 complex in vivo. I also present genetic and biochemical evidence that the yeast amphiphysin proteins, Rvs161 and Rvs167, function together during vegetative growth and during mating. In addition, I have identified an essential role for the SH3 domain of Rvs167 in the absence of the actin cytoskeleton proteins Sla1 and End3. My work identifies novel roles for Crn1 as a regulator of Arp2/3-dependent actin nucleation, provides evidence that the activity of Crn1 may be regulated by phosphorylation and shows evidence for a role for the Rvs161--167 complex in a variety of cellular processes, including mating.
Novel jumping behaviour in pre-pupation larvae of Calindoea trifascialis (Lepidoptera: Thyrididae): Movement path analysis and functional significance

The pre-pupation wandering stage caterpillar of the Southeast Asian moth Calindoea trifascialis constructs a leaf roll that detaches from the leaf and jumps across the ground for about 3 -- 4 days. The jump frequency was correlated linearly with temperature (about 1 jump/sec at 29°C). Correlated random walk and fractal dimension path analyses showed net squared displacements higher than predicted by a CRW, with straighter paths at large spatial scales. Movement paths were correlated with the direction of brightest light. Rearing experiments with pupal retreats showed high mortality from predation on the ground, but even higher mortality resulted from sun exposure. In full sun, pupal retreat temperature was higher and humidity lower than in feeding retreats. Temperatures in pupal retreats were higher than ambient air, sometimes exceeding lethal temperatures. I interpret jumping path orientation as an efficient search strategy for the caterpillar to find shade, given limited perception.
The role of tumour necrosis factor-[alpha] in an animal model of Kawasaki disease

Kawasaki disease (KD) is the most common cause of multisystem vasculitis in childhood. Its propensity for aneurysm formation makes KD quite unique among coronary artery diseases, and the leading cause of pediatric acquired heart disease in the developed world. Tumour necrosis factor-alpha (TNFalpha) is a pleiotropic inflammatory cytokine elevated during the acute phase of KD. In a murine model of KD, rapid TNFalpha production occurs in the peripheral immune system after disease induction. This immune response becomes site-directed, with migration to coronary arteries dependent on TNFalpha mediated events. Production of TNFalpha in the heart is coincident with the presence of inflammatory infiltrate at the coronary arteries, which persists during aneurysm development. Ablation of TNFalpha effector functions abrogated inflammation and elastin breakdown in coronary vessels, rendering mice resistant to coronary arteritis and aneurysm formation. Thus, TNFalpha is necessary for development of coronary artery lesions in an animal model of Kawasaki disease.