The 21-dehydroxylation of corticosteroids: evidence for an enol intermediate and the hydroxylation of steroids by fungal cyto-chrome P450: evidence for a stepwise mechanism

Two enzyme mechanisms were examined: the 21-dehydroxylation of corticosteroids by the anaerobe Eubacterium l en tum, and the hydroxylation of steroids by fungal cytochrome P450. Deuterium labelling techniques were used to study the enzymic dehydroxylation. Corticosteroids doubly labelled (2H) at the C-21 position were incubated with a culture of Eubacterium lentum. It was found that t he enzymic dehydroxylation proceeded with the loss of one 2H f rom C-21 per molecule of substrate. The kinetic isotope ef fect f or the reaction was found to be k~kD = 2. 28. These results suggest that enzyme/substr ate binding in this case may proceed via t he enol form of the substrate. Also , it appears that this binding is, at least in part, the rate determining step of t he reaction. The hydroxylation of steroids by fungal cytochrome P450 was examined by means of a product study. Steroids with a double bond at the A8 (9), ~( lO ), or ~ (ll) position were synthesized. These steroids were then incubated with fungal strains known to use a cytochrome P450 monooxygenase to hydroxylate at positions allylic to these doubl e bonds. The products formed in these incubations indicated that the double bonds had migrated during allylic hydroxylat ion. This suggests that a carbon centred radical or ion may be an intermediate i n the cytochrome P450 cat alytic cycle.

The Canada Southern Railway, extending from Detroit and Toledo to Buffalo and Niagara Falls, forms the quickest and most attractive route between the west and the east.

Includes routes and rates: p.33-64.

Factors affecting performance proficiency : a case study involving intermediate piano students

The goal of this study was to determine the effect of a number of factors on the performance proficiency of three intermediate piano students having different learning styles, all of whom shared the same teacher. Four sets of data were collected in this investigation: the methodology of the teacher; the practice behaviour of the participants; the effect of intrinsic factors, such as participant attitude, motivation, and ownership of learning; and the effect of extrinsic factors that included parental influence, and participants' school- and employment-related responsibilities. Performance proficiency and assessment of practice behaviour were measured by three external, professionallyqualified music examiners. Performance proficiency varied to some extent between participants, but they shared similar practice behaviours. Learning style does not, therefore, affect practice behaviour. Although they planned their practice time, participants did not show much evidence of monitoring the quality of their practice. On the other hand, participants showed positive attitude; they were motivated to learn; and they were observed to plan their practice time, all indicators of, among other things, positive influence of the teacher and parents. Participants showed evidence that these constructive habits were a denominator common to both their schoolwork and piano practice. It was apparent that, except for learning style, all factors examined had an effect on performance proficiency. Performance proficiency is, therefore, influenced by a large web of factors, a finding that is instructive for classroom teachers. Teachers need to avoid the temptation to teach toward performance expectations. Emphasis should be placed instead on teaching and assessing formative learning strategies.

Custom House Niagara forms, 1833

In 1833 William Clarke, the collector of customs at Niagara, completed and signed four forms for the movement of goods between Niagara and York, and Niagara and Brantford. The forms were issued to the firm of Lewis & Gray, James Armstrong, J.A. Wilks, and William Blackely. The goods being transported included scythes, corn brooms, hide whips, sacks, snuff, shovels, spades and two apple trees.

The Impact of a Text-Reader Support Program on Intermediate Students' Reading Comprehension

This study examined the efficacy of providing four Grade 7 and 8 students with reading difficulties with explicit instruction in the use of reading comprehension strategies while using text-reader software. Specifically, the study explored participants' combined use of a text-reader and question-answering comprehension strategy during a 6-week instructional program. Using a qualitative case study methodology approach, participants' experiences using text-reader software, with the presence of explicit instruction in evidence-based reading comprehension strategies, were examined. The study involved three phases: (a) the first phase consisted of individual interviews with the participants and their parents; (b) the second phase consisted of a nine session course; and (c) the third phase consisted of individual exit interviews and a focus group discussion. After the data collection phases were completed, data were analyzed and coded for emerging themes, with-quantitativ,e measures of participants' reading performance used as descriptive data. The data suggested that assistive technology can serve as an instructional "hook", motivating students to engage actively in the reading processes, especially when accompanied by explicit strategy instruction. Participants' experiences also reflected development of strategy use and use of text-reader software and the importance of social interactions in developing reading comprehension skills. The findings of this study support the view that the integration of instruction using evidence-based practices are important and vital components in the inclusion oftext-reader software as part of students' educational programming. Also, the findings from this study can be extended to develop in-class programming for students using text-reader software.

Using Effective Teaching Strategies and Personality Type to Enhance the Mathematics Classroom: A Handbook for Intermediate Math Teachers

This project addressed the need for more insightful, current, and applicable resources for intermediate math teachers in Canadian classrooms. A need for a handbook in this division seemed warranted by a lack of government resource support. Throughout an extensive review of the literature, themes and topics for the handbook emerged. The handbook was designed to not only provide educators with examples of effective teaching strategies within the mathematics classroom but to also inform them about the ways in which their personal characteristics and personality type could affect their students and their own pedagogical practices. Three teaching professionals who had each taught in an intermediate math class within the past year evaluated the handbook. The feedback received from these educators was directly applied to the first draft of the handbook in order to make it more accessible and applicable to other math teachers. Although the handbook was written with teachers in mind, the language and format used throughout the manual also make it accessible to parents, tutors, preservice education students, and educational administrators. Essentially, any individual who is hoping to inspire and educate intermediate math students could make use of the content within the handbook.

Camp Niagara Field Site States Forms from July to October 1916

A set of forms which was held together by a string. The title page is brittle and crumbling. Each page is dated and signed either by the Colonel or Lieutenant Colonel A.A.G. [Assistand Adjutant General] Niagara.

Teachers’ Beliefs and Perceptions of Bullying and Bullying Prevention Initiatives

While bullying prevention programs appear to be decreasing the number of bullying incidents overseas, bullying prevention programs here in Canada have not been proving as effective. Evaluations of bullying prevention programs often focus on the outcomes and neglect to examine the training regimen for teachers. As teachers are on the front lines of bullying prevention programs, the current study explored teachers’ beliefs about the various types of bullying, their perceptions of their own abilities (e.g., teacher bullying prevention efficacy (TBPE), self-concept, and theory of mind) to implement bullying prevention initiatives, and how the school climate may influence their efficacy beliefs. Participants in the current study were 61 Canadian teachers (n = 51 women), predominantly from Ontario. Participating teachers represented all elementary division levels (primary, junior, and intermediate). Participants’ teaching experience ranged from zero years of teaching (pre-service) to 28 years of experience (M = 10.50, SD = 7.35). It was found that participants reported a relatively high TBPE score, which was related to their likely intervention in cyberbullying situations but not for other forms of bullying situations. It was found that teachers were most likely to intervene in physical bullying than verbal, relational, and cyberbullying, respectively. TBPE was influenced by the school climate. Teachers’ scores on the theory of mind scale was not a significant indicator of any teachers’ bullying beliefs. Analyses exploring the relationship between bullying beliefs and self-concept, morality predicted teachers TBPE scores and the likelihood of intervention. Teachers’ recommendations for bullying prevention training and school bullying prevention programs were explored. Results are discussed in terms of implications for practice and future research.

Sport Values of Bantam, Midget and Intermediate Female Hockey Players and Their Minor Hockey Associations

The sport values of female hockey players and their minor hockey associations were explored to better inform a values-based approach for adult-managed minor hockey. Data were collected from 294 participatory HL and competitive Rep players (12-22 years of age) using the Youth Sport Values Questionnaire-2 and from 30 hockey association board members using a modified YSVQ-2. Results indicated player importance (VI) ratings for Moral (M = 4.08) and Competence (M = 4.15) values were not significantly different but were significantly higher than Status (M = 2.11) value. Significant weak relationships between age and competition level versus VI ratings were found. There were medium/ high Moral, medium/ low Competence and high/ high Status value congruence between Rep and HL Player-Board Members, respectively. Based upon the findings, girls’ minor hockey associations need to recognize the values female youth players prioritize, and ensure each is considered within a values-based decision-making approach to governance.

Working Memory in the Junior/Intermediate Classroom

This research project explored the connection between working memory and children’s learning. The project created a resource titled Working Memory Strategies for the Junior/ Intermediate Educator: A Handbook based on a literature review, the deconstruction of theoretical and empirical studies, teacher resources, and findings from a needs assessment completed by teachers that together show there is insufficient support for teachers working with students who have deficits in working memory along with other common classroom learning disabilities. As learning disabilities become more common in the classroom that increasingly affect working memory in a majority of cases, teachers must be prepared not only to address specific symptoms of the conditions, but also to help students learn how to navigate and become aware of their working memory ability. The handbook thus was developed as a useful resource for teachers looking to expand their knowledge about how learning occurs. A needs assessment completed by junior and intermediate division teachers in Ontario helped determine what educators found most important for inclusion in the handbook, and the same teachers were offered the opportunity to review the completed handbook. Teacher participants provided constructive feedback and indicated that the handbook would be a valuable resource for them and their colleagues when working with students who have working memory issues. It was suggested that the handbook would be useful when creating students’ Individual Education Plans and that the assessment checklist included in the handbook would be an excellent resource for teachers collecting data regarding students’ working memory and ability to learn.

Functional Forms and Educational Production Functions

Different Functional Forms Are Proposed and Applied in the Context of Educational Production Functions. Three Different Specifications - the Linerar, Logit and Inverse Power Transformation (Ipt) - Are Used to Explain First Grade Students' Results to a Mathematics Achievement Test. with Ipt Identified As the Best Functional Form to Explain the Data, the Assumption of Differential Impact of Explanatory Variables on Achievement Following the Status of the Student As a Low Or High Achiever Is Retained. Policy Implications of Such Result in Terms of School Interventions Are Discussed in the Paper.

Ancrage de l'idéologie de l'Union des producteurs agricoles et de l'utopie de l'Union paysanne dans des significations imaginaires sociales.

Le but de cette thèse est de découvrir l'idéologie de l'Union des producteurs agricoles et l'utopie de l'Union paysanne et de les interpréter à la lumière de "significations imaginaires sociales" déterminantes de notre période historique. Dans la première partie de notre thèse, nous présentons l'évolution de l'imaginaire social du syndicalisme agricole québécois de 1924 à 2005. Nous distinguons quatre périodes et notre étude s'attarde à la dernière, c'est-à-dire celle qui débute en 2001 avec la naissance de l'Union paysanne. Afin d'étudier cette période nous présentons d'abord l'imaginaire social de la société, c'est-à-dire une configuration de significations imaginaires sociales (SIS) - des "idées-valeurs" générales et "englobantes" - qui fait qu'une société est ce qu'elle est et qu'elle ne pourrait être autrement compte tenu de son noyau de SIS. Ensuite, nous constatons que les travaux d'auteurs importants nous permettent de parler de niveaux et types d'imaginaires sociaux et d'établir des relations entre ces niveaux et formes d'imaginaires sociaux. C'est par l'entremise de la problématique générale agriculture-ruralité que nous démontrons, dans la deuxième partie de cette thèse, que des imaginaires sociaux "intermédiaires" - l'idéologie de l'UPA et l'utopie de la "minorité active", l'UP - permettent, en les ancrant dans quelqu'un et dans quelque chose, d'une part de découvrir les SIS de l'imaginaire social de la société et, d'autre part, de comprendre et d'interpréter ces deux imaginaires sociaux à la lumière des SIS. La problématique agriculture-ruralité est "opérationnalisée" à l'aide des trois dimensions suivantes: rapport à soi, rapport à l'autre et rapport à la nature. Le rapport à soi dévoile que la sphère du travail de l'agriculteur-éleveur dans l'idéologie de l'UPA correspond à la "sphère de la nécessité" qui implique notamment l'hétéronomie des agriculteurs, alors que l'utopie de l'UP la souhaite à la fois comme "sphère de la nécessité" et comme sphère de l'autonomie. Le rapport à l'autre permet de découvrir une utopie préconisant l'égalité des chances entre différents types d'agriculteurs et d'agricultures et entre la relève et les agriculteurs établis ainsi que l'égalité politique en territoire rural agricole. Dans l'idéologie de l'UPA, l'inégalité des chances et l'inégalité politique sont discutables mais inéluctables. Enfin, abstraction faite des nuances, la relation agriculture et nature est à l'utopie de l'UP ce que la relation agriculture ou nature est à l'idéologie de l'UPA. La construction partielle de l'idéologie et de l'utopie, nous permet, dans la troisième et dernière partie de cette thèse, d'y découvrir les SIS et de démontrer que l'utopie trouve son sens et sa cohérence en l'interprétant par l'entremise du naturalisme-écologie, de l'"autonomie" et de l'"autolimitation" comme SIS dominantes et de l'"expansion illimitée de la maîtrise rationnelle" (technique) et du capitalisme (économique) comme SIS "secondaires". Nous découvrons l'inverse dans l'idéologie de l'UPA. Les SIS dominantes et les SIS "secondaires" de l'utopie de l'UP sont respectivement les SIS secondaires et les SIS dominantes sous-jacentes à l'idéologie de l'UPA, ce qui correspond à la configuration des SIS dominantes de l'imaginaire social des sociétés constitutives de l'Occident contemporain.

Ring-opening of cycloalkane epoxides and aziridines with aromatic amines : toward the total synthesis of pactamycin

Résumé Cette thèse consiste en trois thèmes résumés dans les paragraphes ci-dessous. L’influence de différents groupements protecteurs du groupe hydroxyle lors des réactions d’ouverture des cis- et trans- 3-hydroxy-1,2-époxycycloalcanes a été étudiée. Il a été montré que Yb(OTf)3 constituait un catalyseur doux pour l’ouverture régiosélective de cycles afin d’obtenir les -anilino cycloalcanols correspondants avec de bons rendements. Le chauffage du milieu réactionnel dans le toluène comme solvant a permis d’augmenter la cinétique de la réaction, au dépend du rendement. La partie aniline a été régiosélectivement introduite en position vicinale du groupe hydroxyle ou éther afin d’obtenir un unique régioisomère. La même tendance a été observée avec les époxydes du 3-azidocyclohex-1-ène et du 3-carbamate correspondant. Le temps de réaction a été réduit lorsque Yb(OTf)3 a été dissous dans l’acétonitrile. Le triflate d’ytterbium (III) a également été utilisé comme catalyseur pour l’ouverture de cycle régiosélective d’aziridines non-activées sur des cyclohexanes portant des substituants azotures ou éthers de benzyle. L’ion azoture ou l’aniline forment les produits trans correspondants, donnant alors accès à des diamines vicinales avec de bons rendements. Un éther ω-alcoxy p-méthoxybenzylique racémique, inhibiteur de HDAC, a été ainsi préparé en huit étapes synthétiques (rendement total de 26%) à partir du 1-((tert-butyldiphénylsilyl)oxy)hept-6-èn-2-ol. Ceci représente un progrès par rapport à la précédente méthode (9 étapes, rendement total de 16%). La métathèse croisée se montre particulièrement efficace et pratique dans cette stratégie et l’alkylation par le trichloroacétimidate de p-méthoxybenzyle en présence de Sc(OTf)3 améliore le rendement global de la synthèse. Un aminoalcool présent dans la pactamycine et contenant le squelette carboné, les groupements fonctionnels et la stéréochimie requise a été synthétisé en 27 étapes à partir de la L-thréonine. La méthodologie décrite dans cette thèse permet la synthèse de cet intermédiaire clé à l’échelle multigramme.

Développement de l’activité rythmique chez l’embryon du poisson-zébré

Les circuits neuronaux peuvent générer une panoplie de rythmes. Nous pouvons séparer les mécanismes de création de ces rythmes en deux grands types. Le premier consiste de circuits contrôlés par des cellules « pacemakers », ayant une activité rythmique intrinsèque, comme dans le ganglion stomatogastique des crustacés. Le deuxième consiste de circuits multi-neuronaux connectés par un réseau synaptique qui permet une activité rythmique sans la présence de neurones pacemakers, tel que démontré pour les circuits de la nage chez plusieurs vertébrés. Malgré nos connaissances des mécanismes de rhythmogénèse chez les vertébrés adultes, les mécanismes de la création et la maturation de ces circuits locomoteurs chez les embryons restent encore inconnus. Nous avons étudié cette question à l’aide du poisson-zébré où les embryons débutent leur activité motrice par des contractions spontanées alternantes à 17 heures post-fertilisation (hpf). Des études ont démontré que cette activité spontanée n’est pas sensible aux antagonistes de la transmission synaptique chimique et ne requiert pas le rhombencéphale. Après 28 hpf, les embryons commencent à nager et se propulser en réponse au toucher. Des études antérieures on démontré que l’apparition de la nage nécessite le rhombencéphale et la transmission synaptique chimique. Cette thèse explore la possibilité que ces changements comportementaux représentent la progression d’un circuit contrôle par un pacemaker à un circuit ou le rythme provient d’un circuit distribué. En mesurant le groupement des contractions de l’activité spontanée, plutôt que la fréquence moyenne, nous avons découvert une nouvelle forme d’activité spontanée qui débute à 22 hpf. Cette activité consiste de deux contractions alternantes à succession très rapide. Contrairement à l’activité spontanée présente dès 17 hpf cette nouvelle forme d’activité requiert le rhombencéphale et la transmission synaptique chimique, comme démontré pour la nage qui apparait à 28 hpf. Cette forme de comportement intermédiaire représente potentiellement une étape transitoire lors de la maturation des circuits moteurs.