22 resultados para Biochemical Activities
em Brock University, Canada
Resumo:
Although much research has explored computer mediated communication for its application in second language instruction, there still exists a need for empirical results from research to guide practitioners who wish to introduce web-based activities into their instruction. This study was undertaken to explore collaborative online task-based activities for the instruction of ESL academic writing. Nine ESL students in their midtwenties, enrolled at a community college in Ontario, engaged in two separate online prewriting activities in both a synchronous and an asynchronous environment. The students were interviewed in order to explore their perceptions of how the activities affected the generation and organization of ideas for academic essays. These interviews were triangulated with examples of the students' online writing, nonparticipatory observations of the students' interactions, and a discussion with the course instructor. The results of the study reveal that a small majority of students felt that brainstorming in writing with their peers in an asynchronous online discussion created a grammatical and lexical framework that supported idea generation and organization. The students did not feel that the synchronous chat activity was as successful. Although they felt that this activity also contributed to the generation of ideas, synchronous chat introduced a level of difficulty in communication that hindered the students' engagement in the task and failed to assist them with the organization of their ideas. The students also noted positive aspects of the web-based activities that were not related to prewriting tasks, for example, improved typing and word processing skills. Directions for future research could explore whether online prewriting activities can assist students in the creation of essays that are syntactically or lexically complex.
Resumo:
Catharanthlls rosellS (L.) G Don is a commercially significant flower species and in addition is the only source of the monoterpenoid indole alkaloids (MIA) vinblastine and vincristine, which are key pharmaceutical compounds that are used to combat a number of different cancers. Therefore, procurement of the antineoplastic agents is difficult but essential procedure. Alternatively, CatharanthllS tissue cultures have been investigated as a source of these agents; however they do not produce vindoline, which is an obligate precursor to vinblastine and vincristine. The interest in developing high MIA cultivars of Catharantlws rosellS has prompted metabolic profiling studies to determine the variability of MIA accumulation of existing flowering cultivars, with particular focus on the vindoline component ofthe pathway. Metabolic profiling studies that used high performance liquid chromatography of MIAs from seedlings and young leaf extracts from 50 different flowering cultivars showed that, except for a single low vindoline cultivar (Vinca Mediterranean DP Orchid), they all accumulate similar levels of MIAs. Further enzymatic studies with extracts from young leaves and from developing seedlings showed that the low vindoline cultivar has a IO-fold lower tabersonine-16-hydroxylase activity than those of CatharanthllS rosellS cv Little Delicata. Additionally, studies aimed at metabolic engineering ofvindoline bios}l1thesis in Catharanthus rosellS hairy root cultures have been performed by expressing the last step in vindoline biosynthesis [Dcacetylvindoline-4-0- acetyltransferase (DAT)]. Enzymatic profiling studies with transformed hairy roots have confirmed that over-expressing DAT leads to lines with high levels of O-acetyltransferase activity when compared to non-expressing hairy roots. One particular DA T over111 expressing hairy root culture (line 7) contained 200 times the OAT activity than leaves of control lines. Additional MIA analyses revealed that DAT over-expressing hairy roots have an altered alkaloid profile with significant variation in the accumulation of h6rhammericine. Further analysis of transformed hairy root line 7 suggests a correlation between the expression of OAT activity and h6rhammericine accumulation with root maturation. These studies show that metabolic and selective enzymatic profiling can enhance our ability to search for relevant MIA pathway mutants and that genetic engineering with appropriate pathway genes shows promise as a tool to modify the MIA profile of Catharanthus roseus.
Resumo:
This is a qualitative study exploring the physical activity patterns of a group of women with physical disabilities through their lifespan. In-depth interviews were done with a group of 6 women aged 1 9 to 3 1 . The data were analyzed via content and demographic strategies. Participants in this study reported that their physical activity patterns and their experiences related to their physical activity participation changed over their lives. They were most physically active in their youth (under 14 years of age) and as they reached high school age (over 14 years of age) and to the present time, they have become less physically active. They also reported both affordances and constraints to their physical activity participation through their lifespan. In their youth, they reported affordances such as their parents' assistance, an abundance of available physical activity opportunities, and independent unassisted mobility, as all playing an important factor in their increased youth physical activity. In adulthood, the participants' reported less time, fewer opportunities for physical activity, and reliance on power mobility as significant constraints to their physical activity. The participants reported fewer constraints to being physically active in their youth when compared to adulthood. Their reasons for participation in physical activity changed from fun and socialization in their youth instead of for maintenance of health, weight, and function in adulthood. These affordances, constraints and reasons for physical activity participation were supported in the literature.
A biochemical predictor of performance during mesophilic anaerobic fermentation of starch wastewater
Resumo:
The aim of this study was to determine the potential of biochemical parameters, such as enzyme activity and adenosine triphosphate (ATP) levels, as monitors of process performance in the Upflow Anaerobic Sludge Blanket (UASB) reactor utilizing a starch wastewater. The acid and alkaline phosphatase activity and the ATP content of the UASB sludge were measured in response to changes in flow rate and nutrient loading. Conventional parameters of process performance, such as gas production, acetic acid production, COD, phosphorus, nitrogen and suspended solids loadings and % COD removal were also monitored. The response of both biochemical and conventional parameters to changing process conditions was then compared. Alkaline phosphatase activity exhibited the highest activity over the entire study perioda A high suspended solids loading was observed to upset the system in terms of gas production, acetic acid production and % COD removala The initial rate of increase in alkaline phosphatase activity following an increase in loading was four times as great during process upset than under conditions of good performance. The change in enzyme actiVity was also more sensitive to process upset than changes in acetic acid production. The change in ATP content of the sludge with time suggested that enzyme actiVity was changing independently of the actual viable biomass present. The bacterial composition of the anaerobic sludge granules was similar to that of other sludge bed systems, at the light and scanning electron microscope level. Isolated serum bottle cultures produced several acids involved in anaerobic carbohydrate metabolism. The overall performance of the UASB system indicated that higher loadings of soluble nutrients could have been tolerated by the system.
Resumo:
I am a part-time graduate student who works in industry. This study is my narrative about how six workers and I describe shop-floor learning activities, that is learning activities that occur where work is done, outside a classroom. Because this study is narrative inquiry, you wilileam about me, the narrator, more than you would in a more conventional study. This is a common approach in narrative inquiry and it is important because my intentions shape the way that I tell these six workers' stories. I developed a typology of learning activities by synthesizing various theoretical frameworks. This typology categorizes shop-floor learning activities into five types: onthe- job training, participative learning, educational advertising, incidental learning, and self-directed learning. Although learning can occur in each of these activities in isolation, it is often comprised of a mixture of these activities. The literature review contains a number of cases that have been developed from situations described in the literature. These cases are here to make the similarities and differences between the types of learning activities that they represent more understandable to the reader and to ground the typology in practice as well as in theory. The findings are presented as reader's theatre, a dramatic presentation of these workers' narratives. The workers tell us that learning involves "being shown," and if this is not done properly they "learn the hard way." I found that many of their best case lean1ing activities involved on-the-job training, participative learning, incidentalleaming, and self-directed learning. Worst case examples were typically lacking in properly designed and delivered participative learning activities and to a lesser degree lacking carefully planned and delivered on-the-job training activities. Included are two reflective chapters that describe two cases: Learning "Engels" (English), and Learning to Write. In these chapters you will read about how I came to see that my own shop-floor learning-learning to write this thesis-could be enhanced through participative learning activities. I came to see my thesis supervisor as not only my instructor who directed and judged my learning activities, but also as a more experienced researcher who was there to participate in this process with me and to help me begin to enter the research community. Shop-floor learning involves learners and educators participating in multistranded learning activities, which require an organizational factor of careful planning and delivery. As with learning activities, which can be multi-stranded, so too, there can be multiple orientations to learning on the shop floor. In our stories, you will see that these six workers and I didn't exhibit just one orientation to learning in our stories. Our stories demonstrate that we could be behaviorist and cognitivist and humanist and social learners and constructivist in our orientation to learning. Our stories show that learning is complex and involves multiple strands, orientations, and factors. Our stories show that learning narratives capture the essence of learning-the learners, the educators, the learning activities, the organizational factors, and the learning orientations. Learning narratives can help learners and educators make sense of shop-floor learning.
Resumo:
This study examined the effectiveness of motor-encoding activities on memory and performance of students in a Grade One reading program. There were two experiments in the study. Experiment 1 replicated a study by Eli Saltz and David Dixon (1982). The effect of motoric enactment (Le., pretend play) of sentences on memory for the sentences was investigated. Forty Grade One students performed a "memory-for-sentences" technique, devised by Saltz and Dixon. Only the experimental group used motoric enactment of the sentences. Although quantitative findings revealed no significant difference between the mean scores of the experimental group versus the control group, aspects of the experimental design could have affected the results. It was suggested that Saltz and Dixon's study could be replicated again, with more attention given to variables such as population size, nature of the test sentences, subjects' previous educational experience and conditions related to the testing environment. The second experiment was an application of Saltz and Dixon's theory that motoric imagery should facilitate memory for sentences. The intent was to apply this theory to Grade One students' ability to remember words from their reading program. An experimental gym program was developed using kinesthetic activities to reinforce the skills of the classroom reading program. The same subject group was used in Experiment 2. It was hypothesized that the subjects who experienced the experimental gym program would show greater signs of progress in reading ability, as evidenced by their scores on Form G of the Woodcock Reading Mastery Test--Revised. The data from the WRM--R were analyzed with a 3-way split-plot analysis of variance in which group (experimental vs. control) and sex were the between subjects variables and test-time (pre-test vs. post-test) was the within-subjects variable. Findings revealed the following: (a) both groups made substantial gains over time on the visual-auditory learning sub-test and the triple action of group x sex x time also was significant; (b) children in the experimental and control groups performed similarly on both the pre- and post-test of the letter identification test; (c) time was the only significant effect on subjects' performance on the word identification task; (d) work attack scores showed marked improvement in performance over time for both the experimenta+ and control groups; (e) passage comprehension scores indicated an improvement in performance for both groups over time. Similar to Experiment 1, it is suggested that several modifications in the experimental design could produce significant results. These factors are addressed with suggestions for further research in the area of active learning; more specifically, the effect of motor-encoding activities on memory and academic performance of children.
Resumo:
Two groups of rainbow trout were acclimated to 20 , 100 , and 18 o C. Plasma sodium, potassium, and chloride levels were determined for both. One group was employed in the estimation of branchial and renal (Na+-K+)-stimulated, (HC0 3-)-stimulated, and CMg++)-dependent ATPase activities, while the other was used in the measurement of carbonic anhydrase activity in the blood, gill and kidney. Assays were conducted using two incubation temperature schemes. One provided for incubation of all preparations at a common temperature of 2S oC, a value equivalent to the upper incipient lethal level for this species. In the other procedure the preparations were incubated at the appropriate acclimation temperature of the sampled fish. Trout were able to maintain plasma sodium and chloride levels essentially constant over the temperature range employed. The different incubation temperature protocols produced different levels of activity, and, in some cases, contrary trends with respect to acclimation temperature. This information was discussed in relation to previous work on gill and kidney. The standing-gradient flow hypothesis was discussed with reference to the structure of the chloride cell, known thermallyinduced changes in ion uptake, and the enzyme activities obtained in this study. Modifications of the model of gill lon uptake suggested by Maetz (1971) were proposed; high and low temperature models resulting. In short, ion transport at the gill at low temperatures appears to involve sodium and chloride 2 uptake by heteroionic exchange mechanisms working in association w.lth ca.rbonlc anhydrase. G.l ll ( Na + -K + ) -ATPase and erythrocyte carbonic anhydrase seem to provide the supplemental uptake required at higher temperatures. It appears that the kidney is prominent in ion transport at low temperatures while the gill is more important at high temperatures. 3 Linear regression analyses involving weight, plasma ion levels, and enzyme activities indicated several trends, the most significant being the interrelationship observed between plasma sodium and chloride. This, and other data obtained in the study was considered in light of the theory that a link exists between plasma sodium and chloride regulatory mechanisms.
Resumo:
The study was undertaken to identify what motivates registered nurses to participate in continuing education activities. The primary questions were whether basic nursing education, employment status, clinical area, and position, as well as readiness for selfdirected learning influenced Canadian nurses' motivational orientations when deciding to participate in continuing education activities. Other individual differences (e.g., age) were also examined. The sample included 142 registered nurses employed at an urban community hospital. Three instruments were used for data collection: the Education Participation Scale, the Self-Directed Learning Readiness Scale, and a nursing survey consisting of demographic questions. Basic nursing education and employment status did not effect motivational orientation or self-directed learning readiness. Clinical area and level of position significantly influenced nurses' decisions to participate in continuing education activities. Motivational orientation had a significant relationship with selfdirected learning readiness. Implications for practice as a result of this study involves program planning and delivery. The identification of the motivational orientations of participants may assist in the development and delivery of continuing education programs that are beneficial, relevant, and address the identified learning needs of participants. Implications for future research also exist in relation to studying different groups of nurses, for example, registered nursing assistants, and investigating related issues, for example, what are the deterrents to participation in continuing education?
Resumo:
This study examined the link between involvement in extracurricular activities and academic success for 504 youth in grades 5 and 7, using the first-year survey data from a longitudinal study conducted by Youth Lifestyle Choices-Community University Research Alliance (YLC-CURA). Specifically, the study investigated whether a linear or curvilinear relation existed between extracurricular activities and academic achievement for both in- and out-of-school activities. It was hypothesized that stress may be a possible mediator in the link between extracurricular activities and achievement Results indicated that students in grades 5 and 7 were involved in club and sport activities both inside and outside of school at fairly equal fi-equencies, with a mean frequency of approximately once a month. The hypothesis that a positive relation j between in- and out-of-school extracurricular activities and achievement was supported. The hypothesis that a curvilinear relation would exist between extracurricular activities and achievement was only supported for out-of-school activities. This finding supports the argument that too much or too little involvement in out-of-school activities is related negatively to a student's academic success; however, a moderate amount of involvement appears to be positive. The hypothesis that there would be a relation between involvement in extracurricular activities and stress level for both in-school and out-ofschool activities was not supported. Results were discussed in terms of educational implications and community resources for extracurricular activities.
Resumo:
The purpose of this study was to compare bone speed of sound (SOS) measured by quantitative ultrasound, circulating levels of IGF- 1 and biochemical markers of bone turnover in pre- (Pr) and post-menarcheal (Po) synchronized swimmers (SS) and controls (NS). Seventy participants were recruited: 8 PrSS, 22 PoSS, 20 PrNS, and 20 PoNS. Anthropometric measures of height, weight, skeletal maturity and percent body fat were taken, and dietary intake evaluated using 24-hour recall. Bone SOS was measured at the distal radius and mid-tibia and blood samples analyzed for IGF-1, osteocalcin, NTx, and 25-OH vitamin D. Results demonstrated maturational effects on bone SOS, IGF-1 and bone turnover (p<0.05), with no differences observed between SS and NS. Main effects were observed for a reduced caloric intake in SS compared to NS (p<0.05). Therefore, SS does not offer additive affects on bone strength but imparts no adverse affects to skeletal health in these athletes.
Resumo:
STOBBS, Lorne,W ABSTRACT Biochemical and Histological Investigations of viral localisation in the hypersensitive reaction of Phaseolus vulgaris L. var Pinto to tobacco mosaic virus infection. The infection of Phaseolus vulgaris L. var Pinto with tobacco mosaic virus (TMV) results in the production of distinct necrotic lesions confining the virus to restricted areas of the leaf surface. Biochemical and histological changes in the leaf tissue as a result of infection have been described. Trace accumulations of fluorescent metabolites, detected prior to lesion expression represent metabolites produced, by the cell in response to virus infection. These substances, are considered to undergo oxidation and in diffusing into adjacent cells, react with cellular constituents causing the death of these cells. Such cellular necrosis in advance of infection effectively limits virus spread. Chromatographic studies on extracts from TMV infected Pinto bean leaf tissue suggests that a number of extra-fluorescent metabolites produced on lesion'expression represent end products of phenolic oxidation r,eactionsoccurring earlier in these cells. Inhibition of phenolic oxidation by ascorbate infiltration or elevated temperature treatment resulted in the absence of extra-fluorescent metabolites and the continued movement of virus in the absence of necrosis. Further studies with i ascorbate infiltration indicated that irreversible necrotic events were determined as early as 12 tci 18 hrs after viral inoculation. Histochemical tests indicated that callose formation was initiated at this time, and occurred in response to necrotisation. Inhibition of necrosis by either ascorbate infiltration or elevated temp8rature treatment resulted in the absence of callose deposition. Scanning electron'micrographs of infected tissue revealed severe epidermal and palisade cell damage. Histochemical tests indicated extensive callose formation in cells bordering the lesion, and suggested the role of callose iTh the blockage of intercellular connections limiting virus movement. The significance of these cellular changes is discussed. ii
Resumo:
Passions are activities that people find important, like or enjoy, and on which they spend large amounts of time. Research examining passions in adolescence has been limited, despite a tendency for adolescents to explore their identity by trying new activities (Dworkin et aI., 2003). The purpose of the present study was to examine the association between adolescent passions and positive adjustment (psychological well-being, optimism, purpose in life, and low risktaking), as well as investigate possible underlying mechanisms for the link between passions and adjustment. High school students (N=2270, 48.7% female) from Southern Ontario completed questionnaires in grades 10, 11, and 12. Path analyses were conducted to examine cross-lag paths among all study variables. Passions predicted higher optimism and purpose, as well as lower negative risk-taking, over time, but these adjustment indicators in tum did not predict higher passions over time. Additionally, positive mood and unstructured leisure activities partially mediated these associations. Passions appears to be important for adolescent adjustment, and may serve as a protective factor or help to foster thriving.
Resumo:
In 2009, the Ontario Government closed the last three remaining large-scale institutions for people with Developmental Disabilities (DD). The purpose of this study is to examine the community-based recreation and leisure activities of 87 adults with DD who have recently moved into the community. Study 1 provided a descriptive insight into the community recreation and leisure activities, and revealed that people with DD engage in low levels of community activities, however are reported to have the desire to engage more often. Staff reported that people with DD do not have the opportunities to engage in their preferable activities. Study 2 investigated the prbspective predictors of the number and frequency of community, recreation and leisure activities and found that a higher level of functioning predicted a greater number of community activities ([beta] = .26, P < .05), while both a higher level of functioning ([beta] = .38,p < .001) and greater preference ([beta] = .23. p < .05) predicted more frequent access to community activities. Future research and the implications of the findings for clinical practice and policy development were discussed.
Resumo:
The purpose of this project was to create a handbook for parents to develop their children's phonological awareness using authentic activities that parents and children can complete together. The handbook aims to provide parents with fundamental background information regarding phonological awareness as well as effective instruction practices, followed by authentic activities that are clearly laid out and easy to implement. Through a comprehensive study of the literature it became evident that parents should be the target audience for the handbook as they have the greatest influence on the development of their young children. Phonological awareness was also found to be an important contributor to early literacy development including oral language skills and reading. The handbook was reviewed by 2 teaching professionals in order to claim face validity of the document. The results of the project indicate that the handbook which was produced meets its goals of creating a product that is easy to use, practical, and effective for both parents and children. The implementation of the handbook in the home environment can benefit children's phonological awareness and in turn improve their oral language and reading abilities.