VictorJuiz/thesis huggingface dataset:
Engulfment among adults with chronic renal disease, a study of self-loss and its correlates

The purpose of this study was to examine engulfment at four phases of chronic renal disease (CRD). Engulfment was defined as the degree to which the self-concept is dominated by illness and was measured by the Modified Engulfment Scale (MES). Study subjects (n = 200) were divided equally among the four phases of CRD: chronic renal insufficiency, predialysis, early dialysis and long-term dialysis. Subjects in dialysis phases, were equally divided between hemodialysis and continuous ambulatory peritoneal dialysis (CAPD). In addition to the MES, the degree of Engulfment was measured using a semantic differential technique and visual analogue scales (VASs). Standardized instruments were used to measure fatigue, uremic symptoms, illness intrusiveness, and depression. Life satisfaction was measured using a VAS developed by the investigator. Focused interviews were conducted with a subsample of subjects representing each phase (n = 47). Engulfment scores were significantly, positively correlated with serum creatinine levels, number of comorbid conditions, uremic symptoms, fatigue, and illness intrusiveness. There was no significant difference in engulfment scores for subjects on hemodialysis as compared with CAPD. As predicted, engulfment scores differed significantly among the four phases. After controlling for the relevant clinical and sociodemographic variables, symptoms and illness intrusiveness contributed significantly to variance in MES scores; however, phase of CRD did not. The degree of engulfment was positively correlated with depression, negatively correlated with life satisfaction, and significantly contributed to these outcomes after controlling for all other variables of interest. Qualitative data supported the importance of symptoms and illness intrusiveness to the engulfing process and also highlighted potential challenges to the self-concept in CRD, such as transitional events, and strategies employed to minimize engulfment such as redefining the self, and maintaining hope. The results of this study indicate that engulfment provides a useful perspective for understanding the impact of chronic physical illness on the self-concept. Study results provide evidence of the reliability and validity of the MES for measuring the impact of illness on the self-concept in CRD. Additionally, the study identifies variables that may be related to engulfment and suggests directions for future research and clinical interventions in this area.
The influence of steam curing on the chloride resistance of high performance concrete

Steam curing is often used in the production of precast concrete. The elevated temperature of steam curing increases the initial rate of strength development allowing for earlier removal of the formwork. Although elevated curing temperatures result in high early strength, long-term strength and durability may be adversely affected. In this study, the chloride penetration resistance of steam-cured concretes containing silica fume alone or in combination with slag was investigated. The water to cement ratio was kept constant, at 0.3, for all concretes. Testing included: (1) Compressive Strength, (2) Rapid Chloride Permeability, (3) Water Sorptivity, (4) Bulk Diffusion, and (5) Chloride Migration. For a given mixture, steam curing was found to decrease chloride resistance. However, the use of supplementary cementing materials significantly reduced the negative effects of steam curing. The performance of a 4% silica fume steam-cured concrete was comparable to that of a 100% OPC ambient-cured concrete.
Investigation of effective supervisory practices in a multicultural context

This quantitative study investigates perceptions of the effectiveness of supervisory practices and the impact of cultural background, experience and age on supervision, from the perspective of the Toronto Catholic District School Board's adult ESL instructors. The study serves as a quality assurance study, and the data are used as a basis for research with the objective to broaden the knowledge of supervision within specific contexts. Survey questions explored issues such as need for support, observation visits, evaluation, feedback, instructor involvement, qualities of supervisors, communication, and methods of achieving positive change. Data indicate that most fundamental to the thesis of this study is instructors' active involvement. As hypothesized, supervisors who are open to collaborative processes and respect the instructor scored high. The findings also point to instructors' cultural background as a variable worth consideration. Situational approach emerged as an approach that best responds to diverse needs in multicultural contexts.
The relationship between ethnic identity and factors of attrition among First Nations students

Many First Nations students enroll in post-secondary education, however, a large majority of them fail to graduate. Those who succeed attribute their success to the teachings of family members and community elders, as well as to a connectedness to First Nations' culture. This study examines the relationship between ethnic identity and factors of attrition among First Nations students. In addition, a sample of Black students was utilized as a comparison group to assess whether the pattern of findings were unique to First Nations students or general findings for minority groups. This research found that among the First Nations students ethnic identity was positively correlated with a sense of belonging, ethnic identity was not significantly correlated with attrition, and that ethnic identity was negatively correlated with seeking support. Finally, it was also found that there were some fundamental differences between the First Nations and Black students, suggesting that the findings for First Nations students were unique.
Nonuniformly hard Boolean functions and uniform complexity classes

Uniform complexity classes are typically defined in terms of resource-bounded Turing machines, while nonuniform complexity classes in terms of families of Boolean circuits of bounded size. It is well known that superpolynomial circuit lower bounds for NP would imply that P [not equal] NP. Interestingly, the same conclusion would follow from some weak circuit 'upper' bounds for EXP . On the other hand, superpolynomial circuit lower bounds for EXP would imply that every BPP machine can be deterministically simulated in subexponential time. Thus, determining the exact relationship between uniform and nonuniform complexity classes is one of the most important tasks in theoretical computer science. In this dissertation, we investigate several problems related to nonuniformly hard Boolean functions and uniform complexity classes. In particular, we argue that it is unlikely that there is a deterministic polynomial-time algorithm for the following minimum circuit size problem (MCSP): given the truth table of a Boolean function 'f' : {0, 1}'n' [right arrow] {0, 1} and a parameter 's' &isin; <math> <f> <blkbd>N</blkbd></f> </math>, decide whether 'f' can be computed by a Boolean circuit of size at most 's'. We also argue that proving the NP-completeness of MCSP would prove that EXP contains a language of superpolynomial circuit complexity, which is an extremely difficult open problem. However, for a weaker nonuniform model of read-once branching programs, we show that EXP contains a language of nearly maximum nonuniform complexity. Exploiting the relationship between nonuniformly hard Boolean functions and efficient pseudorandom generators, we obtain several results relating probabilistic and deterministic complexity classes. In particular, we prove that every probabilistic polynomial-time Turing machine with one-sided error can be simulated by a zero-error probabilistic subexponential-time Turing machine such that this simulation appears correct to all efficient adversaries. We also show that EXP = ZPP iff EE = ZPE, where EE and ZPE are the exponential analogues of the classes EXP and ZPP, respectively. Finally, we define and study a generalization of BPP that has a natural complete problem: given a Boolean circuit, compute its acceptance probability. The new complexity class consists of all real-valued functions ' f' : {0, 1}'n' [right arrow] [0, 1] probabilistically approximable to within any [epsilon] > 0 in time polynomial in 'n' and 1/[epsilon].
Knowledge and communication skills training for high school students with learning disabilities for the acquisition of self-advocacy skills

A knowledge and communication skills program designed to teach self advocacy to high school students who have learning disabilities (LD) was evaluated. Fifty-three adolescents in grades seven through nine, ages 12-17 (mean age 14.8 years), who were identified as LD, participated in the self advocacy study. These students were from three schools in the Montreal Catholic School Board. Twenty-seven students received the self advocacy program and the remaining 26 students were part of an attention control group who received the self advocacy program at the conclusion of the study. Both groups were evaluated using pre- and post-program structured interviews that focused on Knowledge (of learning disabilities, learning style, resources, services, supports, and accommodations, and ability to succeed) and Communication (verbal and non-verbal skills). Academic locus of control was assessed pre- and post-program using the Intellectual Achievement Responsibility Questionnaire. The frequency which students practiced self advocacy was examined every two weeks for approximately three months post-program. Overall, the findings indicate that the Program group significantly improved on all areas of Knowledge and Communication compared to the Attention Control group. In addition, self advocacy skills were maintained over the post-program period. No significant differences were found between the two groups on the measure of academic locus of control. Regression analyses revealed that changes in Knowledge, Communication skills, and internal locus of control predicted frequency of students' self advocacy for accommodations and resources for three months post-program. Overall, the results suggest that the present knowledge and communication skills training program had a significant impact on the students' self advocacy skills.
Implant prosthodontic management of medically treated hypothyroid patients

A retrospective analysis of implant treated patients with a history of medically managed hypothyroidism was conducted to investigate its impact on (i) survival/loss of osseointegrated Brånemark implants, (ii) marginal bone behavior and (iii) prosthodontic management. The charts of patients treated between 1979 and June 2000 were reviewed and patients with reported histories of thyroid disease at the time of surgery were selected. The total patient population group consisted of 27 female patients. They were matched with a control by age, gender, location (jaw and zone) of implants, type of prosthesis and dental status of the opposing arch. Additional factors studied were medical history, medications, smoking habits, and bone quality and quantity. There was no statistical difference in the number of implant failures. The hypothyroid patients had more soft tissue complications and more bone loss in year one of loading when compared to their matched controls. The implant survival outcomes did not influence the prosthodontic treatment plan. This preliminary study suggests that medically controlled hypothyroid female patients treated with implants were not at higher risk of implant failure when compared to matched controls and that a history of controlled hypothyroidism is not a contra-indication for implant therapy with endosseous implants.
From Santiago Atitlán to the Pan Maya movement, national educational reform, local power and social change in Guatemala

This study follows the tenets of the Naturalistic inquiry. It allows the participants in any collective process to tell their own stories. I examine two Guatemalan Mayan non government organisations, ESEDIR and PRODESSA. They follow a 'radically reformist' strategy at both the national and the local level to implement the provisions of the 1996 Peace Accords. Of particular importance to this study is their involvement in promoting educational reform. Internationally, this is an era in which the traditional left is experiencing a theoretical and programmatic crisis. Politically, this crisis has led to the virtual disappearance of the reformist (or revolutionary) political party as the preferred vehicle of social change and the rise in influence of social movements. In Guatemala this has meant the decline in influence of the URNG, the former guerrilla organisation, now a legal left-wing political party, and an expanded role of the Pan Maya movement. The social change strategy of this movement consists primarily of working in the local communities to prepare people to become protagonists in their own development. Thus, the local development councils not only bring specific services to their communities, but in preparing themselves to do this, they enhance the political literacy and organisational capacity of the communities. Many Mayan organisations also work nationally to promote policies and practices designed to meet the pressing needs of the Maya majority of the population. ESEDIR and PRODESSA were chosen as case studies as they represent two Maya organisations that work simultaneously at the local and national level to achieve social change 'from a Maya perspective'. I conclude that Guatemala, despite its uniqueness, is part of an international phenomenon characterised by the emergence of new social movements to provide leadership to previously marginal social sectors. It is unlikely that this movement alone will be able to overcome those social forces that oppose the far-reaching social changes promised by the Peace Accords. However, by creating a strong community base and extracting concessions at the national level, they are creating the preconditions for a long-term process of political struggle which has the potential, in alliance with others, of effecting transformatory social change in Guatemala.
Identifying reading disabilities: Why discrepancy-based definitions do not work

This study addresses the validity of distinguishing whether children who are discrepant in their reading relative to their IQ ("Dyslexics") are different from children who are discrepant in their reading relative to their age ("Poor Readers"). Under the present Ontario education system, governed by The Education Act (Revised Statutes of Ontario, 1990), dyslexics represent a specific group with a reading disability and are treated differently from the normal distribution of poor readers. As such, they have a statutory right to remedial programs. Non-dyslexic poor readers do not have the same right. To evaluate whether discrepancy-based measures are appropriate for distinguishing children with reading disabilities, the present study assessed the reading and reading-related cognitive skills of a cohort of grade 3 children in three different schools in the Greater Toronto Area. From this cohort of 203 children, two groups--the normal reader group and the poor reader group--were identified by their performance on the WRAT-R Reading subtest (Jastak & Wilkinson, 1984). The poor reader group were those children whose scores were <25th percentile; the normal reader group were those children whose scores were >=25th percentile. The third group, the dyslexic group, was "System-Identified" by an Identification, Placement and Review Committee (IPRC) process. In order to be System-identified as dyslexic, a Fun Scale IQ score in the broad average range of 85 or above on the Wechsler Intelligence Scale for Children-Revised (Wechsler, 1974) was required along with a standardized reading test score of at least two years below the expected grade level determined by age on the Standard Reading Inventory (Newcomer, 1986). The findings support the hypothesis that System-identified dyslexics do not constitute a distinct group different from the group commonly identified in the study as poor readers. The data suggest that both groups are reading disabled and share many similar deficits on reading, language and memory tasks. The data also suggest that English as a second language (ESL) learners are more likely to be classified as poor readers. This study suggests that, regardless of language proficiency, both groups should receive the same opportunity for remediation.
Becoming an antiracist educator, Black, South and East Asian perspectives

This thesis utilizes a critical life history methodology to examine the lived experience of eight research participants. Each participant experienced a one year teacher education program at a Canadian university with a focus on antiracist education during the 1994-95 academic year. The participants included three Afro-Caribbean Canadians; three Asian Canadians, (a Korean, a Hong Kong Chinese and a Japanese Canadian); and two East Asian participants--an Indian Catholic Canadian and a Hindu-Muslim Canadian from Guyana. Through a series of intensive interviews and through bi-weekly dialogue journals this research explores the influences from their previous life history that brought them into teaching, particularly into a program committed to antiracist education, and examines their transformation as antiracist educators during their one year teacher education program. Their experiences of racism and marginalisation as a result of their immigrant status or race, both prior to entering the teacher education program as well as during the teacher education year, prove to be defining experiences in their decision to be teachers and in their transformation as activist teachers. These participants draw on the theory of antiracism presented in the program by several of their professors, contest the status quo in their practicum placements and emerge as antiracist teachers. In examining their life history we see the participants moving through a series of idiosyncratic stages from the early rejection of their own race or culture, to a commitment to social justice, not only for their own race or group, but for all marginalised students.
High school students' perceptions of animal mentation and their opinions on animal use in medical research and entertainment

This study explored the relationship between high school students' perceptions of animal mentation and liking of animals with agreement on animal use in medical research and entertainment. Higher judgments of animal mentation and liking were predicted to correlate with lower agreement on animal use. This pattern was believed to occur more prominently in older students than younger ones. Overall, these hypotheses were supported except for liking which correlated negatively with only agreement in medical use. In general, older students agreed more to animal use than the younger students, especially for medicine. Younger students agreed more to animal use in entertainment than medicine. Complexity of ethical arguments to justify animal use was also investigated. Older students were found to use more reasons, elaboration of reasons, and rebuttals in their arguments than the younger students. Overall, cognitive-developmental differences were evident between older and younger students concerning animal perceptions and opinions on animal use.
Millimeter-wave scanning-beam phased array antenna

A scanning-beam array of microstrip patches, each driven by a 180$\sp\circ$ varactor-diode reflective-type analog phase shifter is proposed and implemented at 30.0 GHz. A novel quadrature hybrid including three cascaded microstrip $\lambda$/4 coupled line sections is introduced as part of the phase shifter circuit. The hybrid represented the key for an overall inexpensive design since its high complexity but loose fabrication tolerances permitted a simple printed circuit board construction for the entire phased array. The design for both the hybrid and the patch antennas relied on analysis performed with a moment method program. Measurements with a network analyzer and a coaxial probe determined the phase shift as a function of the control DC bias, for one phase shifter element at a time, in the fully constructed array. The information thus collected was used to bias the phase shifters individually. This original technique solved the problem of component-induced non-uniformities in an analog driven phased array. Sidelobe generation due to phase error was reduced as a result. Beam steering was demonstrated for an array antenna of four microstrip patches and the measured antenna patterns at various scan angles followed the calculations. The antenna 3 dB beamwidth was 15$\sp\circ$ and the left-right scan angle was 35$\sp\circ.$
Analysis of novel transition metals as catalysts for oxygen delignification

Three catalysts, vanadyl sulfate hydrate (VS), ceric(IV) sulfate (CS), and molybdenyl acetylacetonate (MA) were studied for their effectiveness in enhancing oxygen delignification. Bleaching experiments on a mill-produced hardwood kraft pulp under acidic conditions showed that, under acidic conditions, catalytic oxygen delignification is superior in reducing kappa number as compared to an alkaline oxygen delignification stage. Cyclic voltammetry was used to study the redox behaviour of the catalysts. The effectiveness of catalysts in delignifying pulp was correlated with their ability to oxidize lignin model compounds. The voltammogram of VS showed the oxidation of vanadium to be an irreversible one-electron transfer process. VS was found to be effective in catalyzing the oxidation of vanillyl alcohol (a phenolic lignin model compound). CS was found to be the most efficient of the three catalysts with a high reduction potential and reversible electrochemical behaviour. Gas Chromatography analysis of the reaction products between CS and veratryl alcohol (a non-phenolic lignin model compound), carried out in a mini-reactor, clearly illustrated the effectiveness of CS in catalyzing the oxidation of veratryl alcohol.
Structural studies of the chloroplastic ß-carbonic anhydrase from the common garden pea Pisum sativum

Carbonic anhydrases, enzymes that catalyse the reversible hydration of CO2 to HCO3-, occur in three families (designated Ã, ß and ã) that are evolutionarily unrelated to one another. The structures of Ã- and ã-carbonic anhydrase have previously been determined. This work describes the determination of the structure of the ß-carbonic anhydrase from the dicotyledenous plant ' Pisum sativum' at 1.93Å resolution. The structure was determined using a combination of multiple anomalous diffraction off the active site zinc ion and non-crystallographic symmetry averaging. The molecular fold is novel, with a four stranded Rossman fold-like module being supplemented by a five helical subdomain and an extra antiparallel ß-strand. The molecule assembles into an octamer using a novel dimer of dimers of dimers arrangement such that one interaction surface mediates two different types of interaction. The active site is located at the interface between two monomers, with Cys160, His220 and Cys223 binding the catalytic zinc ion and residues Asp162, Gly224, Gln151, Val184, Phe179 and Tyr205 interacting with the bound substrate analogue, acetic acid. Within ß-carbonic anhydrases, two distinct patterns of conservation of critical active site residues are observed, implying two--potentially mechanistically distinct--classes of ß-carbonic anhydrases. Comparison of the ß-carbonic anhydrase active site with that of Ã-carbonic anhydrase reveals that the substrate binding groups have a one to one correspondence. Eleven atoms with corresponding functionality in the two active sites can be superimposed with an root mean squared deviation better than 0.4Å, but only if the mirror image of one of the active sites is used. Therefore, despite differing folds, Ã- and ß-carbonic anhydrase have converged upon a very similar active site design and likely share a common mechanism.