981 resultados para Order of Railway Conductors and Brakemen
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This thesis, based on the results of an organizational ethnography of a university-based feminist organization in Southern Ontario (the Centre), traces how third wave feminism is being constituted in the goals, initiatives, mandate, organizational structure, and overall culture of university-based feminist organizations. I argue that, from its inception, the meanings and goals of the Centre have been contested through internal critique, reflection, and discussion inspired by significant shifts in feminist theory that challenge the fundamental principles of second wave feminism. I identify a major shift in the development and direction of the Centre that occurs in two distinct phases. The first phase of the shift occurs with the emergence of an antioppression framework, which broadens the Centre's mandate beyond gender and sexism to consider multiple axes of identity and oppression that affect women's lives. The second phase of this shift is characterized by a focus on (trans) inclusion and accessibility and has involved changing the Centre's name so that it is no longer identified as a women's centre in order to reflect more accurately its focus on mUltiple axes of identity and oppression. Along with identifying two phases of a major shift in the direction of the Centre, I trace two discourses about its development. The dominant discourse of the Centre's development is one of progress and evolution. The dominant discourse characterizes the Centre as a dynamic feminist organization that consistently strives to be more inclusive and diverse. The reverse discourse undermines the dominant discourse by emphasizing that, despite the Centre's official attempts to be inclusive and to build diversity, little has actually changed, leaving women of colour marginalized in the Centre's dominant culture of whiteness. This research reveals that, while many of their strategies have unintended (negative) consequences, members of the Centre are working to build an inclusive politics of resistance that avoids the mistakes of earlier feminist movements and organizations. These members, along with other activists, actively constitute third wave feminism in a process that is challenging, contradictory, and often painful. A critical analysis of this process and the strategies it involves provides an opportunity for activists to reflect on their experiences and develop new strategies in an effort to further struggles for social justice and equity.
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The purpose of this study was to evaluate the oral health status of residents residing in 2 long-term care facilities and determine if dental hygiene education was required in order to improve their current oral health. The oral health status of 6 independent and 4 dependent individuals residing in 2 long-term care facilities was evaluated. In addition, the current oral health and disease prevention practices employed by 4 caregivers who were responsible for providing oral care to dependent residents in the long-term care facilities were evaluated. Furthermore, an evaluation of the oral care practices of independent residents who were responsible for providing their own care was conducted. Finally, the challenges that caregivers and independent residents faced when performing oral care were determined, and methodological changes were proposed. Using a generic qualitative research methodology, data collection was comprised of semi structured interviews, field observations, and documentation. The oral health status of the residents was reevaluated 3 months later. The findings of this study demonstrated an increase in plaque accumulation, gingival inflammation, and unhealthy gingival tissue colour changes among the residents over the 3-month period. The study revealed that poor oral health among the residents was a result of inadequate oral hygiene care techniques, difficulties accessing oral health care, financial limitations, insufficient care staff, insufficient time for personal care duties, lack of professional development, minimal interprofessional collaboration of health disciplines, and lack of perseverance on the part of the caregivers and residents. Overall, oral health is essential, and maintaining optimal oral health requires increased collaboration and communication between health care providers.
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This investigation has three purposes I to make a comparative chemical study on sediment cores collected for Lake Lisgar (man-made lake in an urban center) and Lake Hunger (natural basin in a rural community) encompassing the time since European settlement I to determine the postglacial chemical history of Lake Hunger, and to determine the vegetational history of the Lake Hunger area from postglacial time to the present. The minus 80 mesh fraction of 108 soil samples and 18 stream sediment samples collected in the vicinity of Lakes' Lisgar and Hunger were analyzed for cold hydrochloric acid soluble lead, zinc, nickel, cobalt, copper, aluminum, sodium, potassium, calcium, magnesium, iron and manganese. Lacustrine sediments from 5 boreholes in the Lake Lisgar basin were collected. Boreholes 1, 2, 3, and 4 were analyzed for palynological and chemical information and Borehole 5 was subjected to pollen and ostracode analysis. Lacustrine sediments from 6 boreholes in the Lake Hunger basin were collected. Palyno- -logical and chemical analysis were performed on Boreholes 1, 2, 3, 4, and 6 and Borehole 5 was analyzed for pollen. In addition, radiocarbon dates were obtained on sediment samples from Boreholes 4 and 5. A total of 8 surface samples were collected from the margins of the Lake Hunger basin and these were chemically analyzed in the laboratory. All of the lacustrine sediments were ashed and analyzed for cold hydrochloric acid soluble lead, zinc, nickel, cobalt, copper, aluminum, sodium, potassium, calcium, magnesium, iron and manganese using a Perkin Elmer 40) Atomic Absorption spectrophotometer. The results . obtained for the 12 elements were expressed as parts per million in dry sediments. It was found that man's influence on the element distribution patterns in the sediments of Lake Lisgar appeared to be related to his urbanizing developments within the lake vicinity, whereas, the rural developments in the vicinity of lake Hunger appeared to have had little effect on the element distribution patterns in the lake sediments. The distribution patterns of lead, zinc, nickel, cobalt, aluminum, magnesium, sodium and potassium are similar to the % ash curve throughout postglacial time indicating that the rate of erosion in the drainage basin is the main factor which controls the concentration of these elements in the sediments of Lake Hunger. The vegetational history, from palynological analysis, of Lake Hunger from postglacial time to the present includes the following stages: tundra, open spruce forest, closed boreal forest, deciduous forest and the trend towards the re-establishment of pine following the clearing of land and the subsequent settlement of the Lake Hunger area by European settlers. The concentrations of some elements (cobalt, nickel, iron, manganese, calcium, magnesium, sodium and potassium) in the sediments of Lake Hunger appears to be higher during pre-cultural compared to post-cultural times. At least one complete postglacial record of the chemical history within a lake basin is necessary in order to accurately assess man's effects on his environment.
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ABSTRACT Introduction The purpose of this study was to assess specific osteoporosis-related health behaviours and physiological outcomes including daily calcium intake, physical activity levels, bone strength, as assessed by quantitative ultrasound, and bone turnover among women between the ages of 18 and 25. Respective differences on relevant study variables, based on dietary restraint and oral contraceptive use were also examined. Methods One hundred women (20.6 ± 0.2 years of age) volunteered to participate in the study. Informed written consent was obtained by all subjects prior to participation. The study and all related procedures were approved by the Brock University Research Ethics Board. Body mass, height, relative body fat, as well as chest, waist and hip circumferences were measured using standard procedures. The 10-item restrained eating subscale of the Dutch Eating Behaviour Questionnaire (DEBQ) was used to assess dietary restraint (van Strien et al., 1986). Daily calcium intake was assessed by the Rapid Assessment Method (RAM) (Hertzler & Frary 1994). Weekly physical activity was documented by the 4-item Godin Leisure-Time Exercise Questionnaire (Godin & Shephard 1985). Bone strength was determined from the speed of sound (SOS) as measured by QUS (Sunlight 7000S). SOS measurements (m/s) were taken of the dominant and non-dominant sides of the distal one third of the radius and the mid-shaft of the tibia. Resting blood samples were collected from all subjects between 9am and 12pm, in order to evaluate the impact of lifestyle factors on biochemical markers of bone turnover. Blood was collected during the early follicular phase of the menstrual cycle (approximately days 1-5) for all subjects. Samples were centrifliged and the serum or plasma was aliquoted into separate tubes and stored at -80°C until analysis. The bone formation markers measured were Osteocalcin (OC), bone specific alkaline phosphatase (BAP) and 25-OH vitamin D. The bone resorption markers measured were the carboxy (CTx) and amino (NTx) terminal telopeptides of type-I collagen crosslinks. All markers were assessed by ELISA. Subjects were divided into high (HDR) and low dietary restrainers (LDR) based on the median DEBQ score, and also into users (BC) and non-users (nBC) of oral contraceptives. A series of multiple one way ANOVA's were then conducted to identify differences between each set of groups for all relevant variables. A two-way ANOVA analysis was used to explore significant interactions between dietary restraint and use of oral contraceptives while a univariate follow-up analysis was also performed when appropriate. Pearson Product Moment Correlations were used to determine relationships among study variables. Results HDR had significantly higher BMI, %BF and circumference measures but lower daily calcium intake than LDR. There were no significant differences in physical activity levels between HDR and LDR. No significant differences were found between BC and nBC in body composition, calcium intake and physical activity. HDR had significantly lower tibial SOS scores than LDR in both the dominant and non-dominant sites. The post-hoc analysis showed that within the non-birth control group, the HDR had significantly lower tibial SOS scores of bone strength when compared to the LDR but Aere were no significant differences found between the two dietary restraint groups for those currently on birth control. HDR had significantly lower levels of OC than LDR and the BC group had lower levels of BAP than the nBC group. Consistently, the follow-up analysis revealed that within those not on birth control, subjects who were classified as HDR had significantly (f*<0.05) lower levels of OC when compared with LDR but no significant differences were observed in bone turnover between the two dietary restraint groups for those currently on birth control. Physical activity was not correlated with SOS scores and bone turnover markers possibly due to the low physical activity variability in this group of women. Conclusion This is the first study to examine the effects of dietary restraint on bone strength and turnover among this population of women. The most important finding of this study was that bone strength and turnover are negatively influenced by dietary restraint independent of relative body fat. In general, the results of the present thesis suggest that dietary restraint, oral contraceptive use, as well as low daily calcium intake and low physical activity levels were widespread behaviours among this population of college-aged women. The young women who were using dietary restraint as a strategy to lose weight, and thus were in the HDR group, despite their higher relative body fat and weight, had lower scores of bone strength and lower levels of markers of bone turnover compared to the low dietary restrainers. Additionally, bone turnover seemed to be negatively affected by oral contraceptives, while bone strength, as assessed by QUS, seemed unaffected by their use in this population of young women. Physical activity (weekly energy expenditure), on the other hand, was not associated with either bone strength or bone tiimover possibly due to the low variability of this variable in this population of young Canadian women.
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An analytical model for bacterial accumulation in a discrete fractllre has been developed. The transport and accumlllation processes incorporate into the model include advection, dispersion, rate-limited adsorption, rate-limited desorption, irreversible adsorption, attachment, detachment, growth and first order decay botl1 in sorbed and aqueous phases. An analytical solution in Laplace space is derived and nlln1erically inverted. The model is implemented in the code BIOFRAC vvhich is written in Fortran 99. The model is derived for two phases, Phase I, where adsorption-desorption are dominant, and Phase II, where attachment-detachment are dominant. Phase I ends yvhen enollgh bacteria to fully cover the substratllm have accllillulated. The model for Phase I vvas verified by comparing to the Ogata-Banks solution and the model for Phase II was verified by comparing to a nonHomogenous version of the Ogata-Banks solution. After verification, a sensitiv"ity analysis on the inpllt parameters was performed. The sensitivity analysis was condllcted by varying one inpllt parameter vvhile all others were fixed and observing the impact on the shape of the clirve describing bacterial concentration verSllS time. Increasing fracture apertllre allovvs more transport and thus more accllffilliation, "Vvhich diminishes the dllration of Phase I. The larger the bacteria size, the faster the sllbstratum will be covered. Increasing adsorption rate, was observed to increase the dllration of Phase I. Contrary to the aSSllmption ofllniform biofilm thickness, the accllffilliation starts frOll1 the inlet, and the bacterial concentration in aqlleous phase moving towards the olitiet declines, sloyving the accumulation at the outlet. Increasing the desorption rate, redllces the dliration of Phase I, speeding IIp the accllmlilation. It was also observed that Phase II is of longer duration than Phase I. Increasing the attachment rate lengthens the accliffililation period. High rates of detachment speeds up the transport. The grovvth and decay rates have no significant effect on transport, althollgh increases the concentrations in both aqueous and sorbed phases are observed. Irreversible adsorption can stop accllillulation completely if the vallIes are high.
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Introduction The question of the meaning, methods and philosophical manifestations of history is currently rife with contention. The problem that I will address in an exposition of the thought of Wilhelm Dilthey and Martin Heidegger, centers around the intersubjectivity of an historical world. Specifically, there are two interconnected issues. First, since all knowledge occurs to a person from within his or her historical age how can any person in any age make truth claims? In order to answer this concern we must understand the essence and role of history. Yet how can we come to an individual understanding ofwhat history is when the meanings that we use are themselves historically enveloped? But can we, we who are well aware of the knowledge that archaeology has dredged up from old texts or even from 'living' monuments of past ages, really neglect to notice these artifacts that exist within and enrich our world? Charges of wilful blindness would arise if any attempt were made to suggest that certain things of our world did not come down to us from the past. Thus it appears more important 2 to determine what this 'past' is and therefore how history operates than to simply derail the possibility for historical understanding. Wilhelm Dilthey, the great German historicist from the 19th century, did not question the existence of historical artifacts as from the past, but in treating knowledge as one such artifact placed the onus on knowledge to show itself as true, or meaningful, in light ofthe fact that other historical periods relied on different facts and generated different truths or meanings. The problem for him was not just determining what the role of history is, but moreover to discover how knowledge could make any claim as true knowledge. As he stated, there is a problem of "historical anarchy"!' Martin Heidegger picked up these two strands of Dilthey's thought and wanted to answer the problem of truth and meaning in order to solve the problem of historicism. This problem underscored, perhaps for the first time, that societal presuppositions about the past and present oftheir era are not immutable. Penetrating to the core of the raison d'etre of the age was an historical reflection about the past which was now conceived as separated both temporally and attitudinally from the present. But further than this, Heidegger's focus on asking the question of the meaning of Being meant that history must be ontologically explicated not merely ontically treated. Heidegger hopes to remove barriers to a genuine ontology by II 1 3 including history into an assessment ofprevious philosophical systems. He does this in order that the question of Being be more fully explicated, which necessarily for him includes the question of the Being of history. One approach to the question ofwhat history is, given the information that we get from historical knowledge, is whether such knowledge can be formalized into a science. Additionally, we can approach the question of what the essence and role of history is by revealing its underlying characteristics, that is, by focussing on historicality. Thus we will begin with an expository look at Dilthey's conception of history and historicality. We will then explore these issues first in Heidegger's Being and Time, then in the third chapter his middle and later works. Finally, we shall examine how Heidegger's conception may reflect a development in the conception of historicality over Dilthey's historicism, and what such a conception means for a contemporary historical understanding. The problem of existing in a common world which is perceived only individually has been philosophically addressed in many forms. Escaping a pure subjectivist interpretation of 'reality' has occupied Western thinkers not only in order to discover metaphysical truths, but also to provide a foundation for politics and ethics. Many thinkers accept a solipsistic view as inevitable and reject attempts at justifying truth in an intersubjective world. The problem ofhistoricality raises similar problems. We 4 -. - - - - exist in a common historical age, presumably, yet are only aware ofthe historicity of the age through our own individual thoughts. Thus the question arises, do we actually exist within a common history or do we merely individually interpret this as communal? What is the reality of history, individual or communal? Dilthey answers this question by asserting a 'reality' to the historical age thus overcoming solipsism by encasing individual human experience within the historical horizon of the age. This however does nothing to address the epistemological concern over the discoverablity of truth. Heidegger, on the other hand, rejects a metaphysical construel of history and seeks to ground history first within the ontology ofDasein, and second, within the so called "sending" of Being. Thus there can be no solipsism for Heidegger because Dasein's Being is necessarily "cohistorical", Being-with-Others, and furthermore, this historical-Being-in-the-worldwith- Others is the horizon of Being over which truth can appear. Heidegger's solution to the problem of solipsism appears to satisfy that the world is not just a subjective idealist creation and also that one need not appeal to any universal measures of truth or presumed eternal verities. Thus in elucidating Heidegger's notion of history I will also confront the issues ofDasein's Being-alongside-things as well as the Being of Dasein as Being-in-the-world so that Dasein's historicality is explicated vis-a-vis the "sending of Being" (die Schicken des S eins).
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This study probed for an answer to the question, "How do you identify as early as possible those students who are at risk of failing or dropping out of college so that intervention can take place?" by field testing two diagnostic instruments with a group of first semester Seneca College Computer Studies students. In some respects, the research approach was such as might be taken in a pilot study. Because of the complexity of the issue, this study did not attempt to go beyond discovery, understanding and description. Although some inferences may be drawn from the results of the study, no attempt was made to establish any causal relationship between or among the factors or variables represented here. Both quantitative and qualitative data were gathered during. four resea~ch phases: background, early identification, intervention, and evaluation. To gain a better understanding of the problem of student attrition within the School of Computer Studies at Seneca College, several methods were used, including retrospective analysis of enrollment statistics, faculty and student interviews and questionnaires, and tracking of the sample population. The significance of the problem was confirmed by the results of this study. The findings further confirmed the importance of the role of faculty in student retention and support the need to improve the quality of teacher/student interaction. As well, the need __f or ~~ills as~e:ss_~ent foll,,-~ed }JY supportiv e_c_ounsell~_I'l9_ ~~d_ __ placement was supported by the findings from this study. strategies for reducing student attrition were identified by faculty and students. As part of this study, a project referred to as "A Student Alert project" (ASAP) was undertaken at the School of Computer Studies at Seneca College. Two commercial diagnostic instruments, the Noel/Levitz College Student Inventory (CSI) and the Learning and Study Strategies Inventory (LASSI), provided quantitative data which were subsequently analyzed in Phase 4 in order to assess their usefulness as early identification tools. The findings show some support for using these instruments in a two-stage approach to early identification and intervention: the CSI as an early identification instrument and the LASSI as a counselling tool for those students who have been identified as being at risk. The findings from the preliminary attempts at intervention confirmed the need for a structured student advisement program where faculty are selected, trained, and recognized for their advisor role. Based on the finding that very few students acted on the diagnostic results and recommendations, the need for institutional intervention by way of intrusive measures was confirmed.
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This research was focussed on the effects of light, solvent and substituents in the molybdenum-catalyzed oxidation of phenylmethyl sulfides with t-Bu02H and on the effect of light in the molybdenum-catalyzed epoxidation of l-octene with t-Bu02H. It was shown that the Mo(CO)6-catalyzed oxidation of phenylmethyl sulfide with t-Bu02H~ at 35°C, proceeds 278 times faster underUV light than under laboratory lighting, whereas the Mo02(acac)2-catalyzed oxidation proceeds only 1.7 times faster under UV light than under normal laboratory lighting. The difference between the activities of both catalysts was explained by the formation of the catalytically active species, Mo(VI). The formation of the Mo(VI) species, from Mo(CO)6 was observed from the IR spectrum of Mo(CO)6 in the carbonyl region. The Mo(CO)6-catalyzed epoxidation of l-octene with t-Bu02H showed that the reaction proceeded 4.6 times faster under UV light than in the dark or under normal laboratory lighting; the rates of epoxidations were found to be the same in the dark and under normal laboratory lighting. The kinetics of the epoxidations of l-octene with t-Bu02H, catalyzed by Mo02(acac)2 were found to be complicated; after fast initial rates, the epoxidation rates decreased with time. The effect of phenylmethyl sulfide on the Mo(CO)6-catalyzed epoxidation of l-octene waS studied. It was shown that instead of phenylmethyl sulfide, phenylmethyl sulfone, which formed rapidly at 85°C, lowered the reaction rate. The epoxidation of l-octene was found to be 2.5 times faster in benzene than in ethanol. The substituent effect on the Mo02(acac)2-catalyzed oxidations of p-OH, p-CHgO, P-CH3' p-H, p-Cl, p-Br, p-CHgCO, p-HCO and P-N02 substituted phenylmethyl sulfides were studied. The oxidations followed second order kinetics for each case; first order dependency on catalyst concentration was also observed in the oxidation of p-CHgOPhSMeand PhSMe. It was found that electron-donating groups on the para position of phenylmethyl sulfide increased the rate of reaction, while electronwithdrawing groups caused the reaction rate to decrease. The reaction constants 0 were determined by using 0, 0- and 0* constants. The rate effects were paralleled by the activation energies for oxidation. The decomposition of t-Bu02H in the presence of M.o (CO)6, Mo02 (acac)2 and VO(acac)2 was studied. The rates of decomposition were found to be very small compared to the oxidation rates at high concentration of catalysis. The relative rates of the Mo02(acac)2-catalyzed oxidation of p-N02PhSMe by t-Bu02H in the presence of either p-CH30PhSMe or PhSMe clearly show that PhSMe and p-CHgOPhSMe act as co-catalysts in the oxidation of p-N02PhSMe. Benzene, mesity1ene and cyclohexane were used to determine the effect of solvent in the Mo02 (acac)2 and Mo(CO)6-catalyzed oxidation of phenylmethyl sulfide. The results showed that in the absence of hydroxylic solvent, a second molecule of t-Bu02H was involved in the transition state. The complexation of the solvent with the catalyst could not be explained.The oxidations of diphenyl sulfoxide catalyzed by VO(acac)2, Mo(CO)6 and Mo02(acac)2 showed that VO(acac)2 catalyzed the oxidation faster than Mo(CO)6 and Mo02 (acac)2_ Moreover, the Mo(CO)6-catalyzed oxidation of diphenyl sulfoxide proceeded under UV light at 35°C.
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Adenoviruses are nonenveloped icosahedral shaped particles. The double stranded DNA viral genome is divided into 5 major early transcription units, designated E1 A, E1 B, and E2 to E4, which are expressed in a regulated manner soon after infection. The gene products of the early region 3 (E3), shown to be nonessential for viral replication in vitro, are believed to be involved in counteracting host immunosurveillance. In order to sequence the E3 region of Bovine adenovirus type 2 (BAV2) it was necessary to determine the restriction map for the plasmid pEA48. A physical restriction endonuclease map for BamHl, Clal, Eco RI, Hindlll, Kpnl, Pstt, Sail, and Xbal was constructed. The DNA insert in pEA48 was determined to be viral in origin using Southern hybridization. A human adenovirus type 5 recombinant plasmid, containing partial DNA fragments of the two transcription units L4 and L5 that lie just outside the E3, was used to localize this region. The recombinant plasmid pEA was subcloned to facilitate sequencing. The DNA sequences between 74.8 and 90.5 map units containing the E3, the hexon associated protein (pVIII), and the fibre gene were determined. Homology comparison revealed that the genes for the hexon associated pV11I and the fibre protein are conserved. The last 70 amino acids of the BAV2 pV11I were the most conserved, showing a similarity of 87 percent with Ad2 pV1I1. A comparison between the predicted amino acid sequences of BAV2 and Ad40, Ad41 , Ad2 and AdS, revealed that they have an identical secondary structure consisting of a tail, a shaft and a knob. The shaft is composed of 22, 15 amino acid motifs, with periodic glycines and hydrophobic residues. The E3 region was found to consist of about 2.3 Kbp and to encode four proteins that were greater than 60 amino acids. However, these four open reading frames did not show significant homology to any other known adenovirus DNA or protein sequence.
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February 28, 1815. Printed by order of the Senate of the United States.
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The St. Catharines and District Council of Women was founded in 1918 and elected as its first president, Mary Malcolmson. In 1910 Mrs. Malcolmson founded North America’s first Girl Guide Association in St. Catharines. The aim of the organization was to work for the betterment of conditions pertaining to the family, community and state. The Council is an umbrella group for various women’s organizations in the area and functions at the provincial, national and international levels and is associated with the United Nations. In the early years the National Council brought in the Victorian Order of Nurses (VON) and started the Women’s Canadian Club. The St. Catharines Council initiated Child Welfare Centres in local churches that grew into the Well Baby Clinics. Women were encouraged to take political office and join committees with much success. In 1929, “Shop at Home” exhibition became an annual event highlighting the services of local merchants. Money raised by the Council was donated to local charities and in 1930 the Council assisted the local Armenian community in building the first Armenian Church in Canada. In 1932 the Council started the Maternal Welfare programme in which Mothers’ Meetings were held weekly with various speakers from the Public Health Department. In 1975 to celebrate International Women’s Year and the 1976 Centennial of the City of St. Catharines, the group sponsored the book Women of Action, 1876-1976, written by two of its members, Lily M. Bell and Kathleen E. Bray. Some time after 1976 the name of the organization changed from St. Catharines Local Council of Women to St. Catharines and District Council of Women. Today the organization functions as an advocacy and educational group.
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A large variety of social signals, such as facial expression and body language, are conveyed in everyday interactions and an accurate perception and interpretation of these social cues is necessary in order for reciprocal social interactions to take place successfully and efficiently. The present study was conducted to determine whether impairments in social functioning that are commonly observed following a closed head injury, could at least be partially attributable to disruption in the ability to appreciate social cues. More specifically, an attempt was made to determine whether face processing deficits following a closed head injury (CHI) coincide with changes in electrophysiological responsivity to the presentation of facial stimuli. A number of event-related potentials (ERPs) that have been linked specifically to various aspects of visual processing were examined. These included the N170, an index of structural encoding ability, the N400, an index of the ability to detect differences in serially presented stimuli, and the Late Positivity (LP), an index of the sensitivity to affective content in visually-presented stimuli. Electrophysiological responses were recorded while participants with and without a closed head injury were presented with pairs of faces delivered in a rapid sequence and asked to compare them on the basis of whether they matched with respect to identity or emotion. Other behavioural measures of identity and emotion recognition were also employed, along with a small battery of standard neuropsychological tests used to determine general levels of cognitive impairment. Participants in the CHI group were impaired in a number of cognitive domains that are commonly affected following a brain injury. These impairments included reduced efficiency in various aspects of encoding verbal information into memory, general slower rate of information processing, decreased sensitivity to smell, and greater difficulty in the regulation of emotion and a limited awareness of this impairment. Impairments in face and emotion processing were clearly evident in the CHI group. However, despite these impairments in face processing, there were no significant differences between groups in the electrophysiological components examined. The only exception was a trend indicating delayed N170 peak latencies in the CHI group (p = .09), which may reflect inefficient structural encoding processes. In addition, group differences were noted in the region of the N100, thought to reflect very early selective attention. It is possible, then, that facial expression and identity processing deficits following CHI are secondary to (or exacerbated by) an underlying disruption of very early attentional processes. Alternately the difficulty may arise in the later cognitive stages involved in the interpretation of the relevant visual information. However, the present data do not allow these alternatives to be distinguished. Nonetheless, it was clearly evident that individuals with CHI are more likely than controls to make face processing errors, particularly for the more difficult to discriminate negative emotions. Those working with individuals who have sustained a head injury should be alerted to this potential source of social monitoring difficulties which is often observed as part of the sequelae following a CHI.
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Rates and products of the oxidation of diphenyl sulfide, phenyl methyl sulfide, p-chlorophenyl methyl sulfide and diphenyl sulfoxide have been determined. Oxidants included t-Bu02H alone, t-Bu02H plus molybdenum or vanadium catalysts and the molybdenum peroxo complex Mo0(02)2*HMPT. Reactions were chiefly carried out in ethanol at temperatures ranging from 20° to 65°C. Oxidation of diphenyl sulfide by t-Bu02H in absolute ethanol at 65°C followed second-order kinetics with k2 = 5.61 x 10 G M~1s"1, and yielded only diphenyl sulfoxide. The Mo(C0)g-catalyzed reaction gave both the sulfoxide and the sulfone with consecutive third-order kinetics. Rate = k3[Mo][t-Bu02H][Ph2S] + k^[Mo][t-Bu02H][Ph2S0], where log k3 = 12.62 - 18500/RT, and log k^ = 10.73 - 17400/RT. In the absence of diphenyl sulfide, diphenyl sulfoxide did not react with t-Bu02H plus molybdenum catalysts, but was oxidized by t-Bu02H-V0(acac)2. The uncatalyzed oxidation of phenyl methyl sulfide by t-Bu02H in absolute ethanol at 65°C gave a second-order rate constant, k = 3.48 x 10~"5 M^s""1. With added Mo(C0)g, the product was mainly phenyl methyl sulfoxide; Rate = k3[Mo][t-Bu02H][PhSCH3] where log k3 = 22.0 - 44500/RT. Both diphenyl sulfide and diphenyl sulfoxide react readily with the molybdenum peroxy complex, Mo0(02)2'HMPT in absolute ethanol at 35°C, yielding diphenyl sulfone. The observed features are mainly in agreement with the literature on metal ion-catalyzed oxidations of organic compounds by hydroperoxides. These indicate the formation of an active catalyst and the complexation of t-Bu02H with the catalyst. However, the relatively large difference between the activation energies for diphenyl sulfide and phenyl methyl sulfide, and the non-reactivity of diphenyl sulfoxide suggest the involvement of sulfide in the production of an active species.
The kinetics and solvent effects on the thermal decomposition of isopropyl peroxide and 1, 2-dioxane
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Rates of H2 formation have been determined for the thermal decomposition of isopropyl peroxide at l30o-l50oC in toluene and methanol and at l400C in isopropyl alcohol and water. Product studies have been carried out at l400C in these solvents. The decomposition of isopropyl peroxide was shown to be unimolecular with energies of activation in toluene, and methanol of 39.1, 23.08 Kcal/mole respectively. It has been shown that the rates of H2 formation in decomposition of isopropyl peroxide are solvent dependent and that the ~ vs "'2';' values (parameters for solvent polarity) givesastraight line. Mechanisms for hydrogen production are discussed which satisfactorily explain the stabilization of the six-centered transition state by the solvent. One possibility is that of conformation stabilization by solvent and the other, a transition state with sufficient ionic character to be stabilized by a polar solvent. Rates of thermal decomposition of 1,2-dioxane in tert-butylbenzene at l40o-l70oC have been determined. The activation energy was found to be 33.4 Kcal/mole. This lower activation energy, compared to that for the decomposition of isopropyl peroxide in toluene (39.1 Kcal/mole) has been explained in terms of ring strain. Decomposition of 1,2 dioxane in MeOH does not follow a first order reaction. Several mechanisms have been suggested for the products observed for decomposition of 1;2-dioxane in toluene and methanol.
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This study probed for an answer to the question, "How do you identify as early as possible those students who are at risk of failing or dropping out of college so that intervention can take place?" by field testing two diagnostic instruments with a group of first semester Seneca College Computer ,Studies students. In some respects, the research approach was such as might be taken in a pilot study_ Because of the complexity of the issue, this study did not attempt to go beyond discovery, understanding and description. Although some inferences may be drawn from the results of the study, no attempt was made to establish any causal relationship between or among the factors or variables represented here. Both quantitative and qualitative data were gathered during four resea~ch phases: background, early identification, intervention, and evaluation. To gain a better understanding of the problem of student attrition within the School of Computer Studies at Seneca College, several methods were used, including retrospective analysis of enrollment statistics, faculty and student interviews and questionnaires, and tracking of the sample population. The significance of the problem was confirmed by the results of this study. The findings further confirmed the importance of the role of faculty in student retention and support the need to improve the quality of teacher/student interaction. As well, the need for skills assessmen~-followed by supportive counselling, and placement was supported by the findings from this study. strategies for reducing student attrition were identified by faculty and students. As part of this study, a project referred to as "A Student Alert Project" (ASAP) was undertaken at the School of Computer Studies at Seneca college. Two commercial diagnostic instruments, the Noel/Levitz College Student Inventory (CSI) and the Learning and Study Strategies Inventory (LASSI), provided quantitative data which were subsequently analyzed in Phase 4 in order to assess their usefulness as early identification tools. The findings show some support for using these instruments in a two-stage approach to early identification and intervention: the CSI as an early identification instrument and the LASSI as a counselling tool for those students who have been identified as being at risk. The findings from the preliminary attempts at intervention confirmed the need for a structured student advisement program where faculty are selected, trained, and recognized for their advisor role. Based on the finding that very few students acted on the diagnostic results and recommendations, the need for institutional intervention by way of intrusive measures was confirmed.