975 resultados para Thesis (M.Ed.)-- Brock University, 1996.
Resumo:
Phascolomyces articulosus genomic DNA was isolated from 48 h old hyphae and was used for amplification of a chitin synthase fragment by the polymerase chain reaction method. The primers used in the amplification corresponded to two widely conserved amino acid regions found in chitin synthases of many fimgi. Amphfication resulted in four bands (820, 900, 1000 and 1500 bp, approximately) as visualized in a 1.2% agarose gel. The lowest band (820 bp) was selected as a candidate for chitin synthase because most amplified regions from other fimgi so far exhibited similar sizes (600-750 bp). The selected fragment was extracted from the gel and cloned in the Hinc n site of pUC19. The derived plasmid and insert were designated ^\5C\9'PaCHS and PaCHS respectively. The plasmid pUC19-PaC/fS was digested by several restriction enzymes and was found to contain BamHl and HincU sites. Sequencing of PaCHS revealed two intron sequences and a total open reading frame of 200 amino acids. The derived polypeptide was compared with other related sequences from the EMBL database (Heidelberg, Germany) and was matched to 36 other fiilly or partially sequenced fimgal chitin synthase genes. The closest resemblance was with two genes (74.5% and 73.1% identity) from Rhizopus oligosporus. Southern hybridization with the cloned fragment as a probe to the PCR reaction showed a strong signal at the fragment selected for cloning and weaker signals at the other two fragments. Southern hybridization with partially digested Phascolomyces articulosus genomic DNA showed a single band. The amino acid sequence was compared with sequences from other chitin synthase gene classes using the CLUSTALW program. The chitin synthase fragment from Phascolomyces articulosus was initially grouped in class n along with chitin synthase fragments from Rhizopus oligosporus and Phycomyces blakesleeanus which also belong to the same class, Zygomycetes. Bootstrap analysis using the neighbor-joining method available by CLUSTALW verified such classification. Comparison of PaCHS revealed conservation of intron positions that are characteristic of chitin synthase gene fragments of zygomycetous fungi.
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The purpose of this qualitative study was to investigate the application of Cognitive Coaching as a school-based professional development program to improve instructional thought and decision making as well as to enhance staff perceptions, coUegiality and school culture. This topic emerged from personal and professional issues related to the role ofthe reflective practitioner in improving the quality of education, yet cognizant of the fact that little professional development was available to train teachers to become reflective. This case study, positioned within the interpretive sciences, focused on three teachers and how their experiences with cognitive coaching affected their teaching practices. Their knowledge, understanding and use of the four stages of instructional thought (preactive, interactive, reflective and projective) were tested before and at the end of eight coaching cycles, and again after two months to determine whether they had continued to use the reflective process. They were also assessed on whether their attitude towards peer coaching had changed, whether their feelings about teaching had become more positive and whether their professional dialogue had increased. Three methods of data collection were selected to assess growth: interviews, observations and joumaling. Analysis primarily consisted of coding and organizing data according to emerging themes. Although the professed aim of cognitive coaching was to teach the process in order that the teachers would become self-analytical and self-modifying, this study found that the value of the coaching, after trust had been established in both the coach and the process, was in the dialoguing and the time set aside to do it. Once the coaching stopped providing the time to dialogue, to examine one's meanings and beliefs, so did the critical self-reflection. As a result ofthe cognitive coaching experience though, all participants grew in their feelings of efficacy, craftsmanship, flexibility, consciousness and interdependence. The actual and potential significance ofthis study was discussed according to implications for teacher supervision, professional development, school culture, further areas of research and to my personal growth and development.
Resumo:
This study was a comparative investigation of face-toface (i.e., proximate) and computer-mediated written (i.e., graphic) pre-writing conferences. The participants in this study were advanced English as a second language students. The 2 types of conferences were compared in terms of textual features, participation, and the . degree to which they were on topic. Moreover, drafts written after the 2 types of conferences were compared in terms of textual features, and the degree to which they were related to the conferences. Students produced an equivalent amount of discourse in an equivalent amount of time in the 2 types of conferences. The discourse in graphic conferences displayed greater lexical range, and some evidence suggests that it was less on-topic. Both these results likely occurred because the graphic conferences contained more discourse demonstrating interactive competence. Participation in graphic conferences was found to be as balanced or more balanced among students, and among students and the group leader combined. Overall, the drafts produced after the 2 types of conferences were of equivalent length and topical range, but some evidence suggests that drafts written after proximate conferences were more related to the conferences.
Resumo:
The value of career education is measured by the extent to which it enhances students' decision making skills regarding career planning. This is referred to as "career maturity". The purpose of this study was to examine what connections could be found between career education and career maturity within one career planning course. A senior level career planning class was studied in depth for one semester and five senior students participated in the study. The five students were interviewed three times during the semester to determine whether, and to what extent, students feel more prepared personally to make decisions as a result of a guided course of instruction. The current trend in education shows an increased emphasis on career education. The government mandates career education, students are in need of career planning courses, and parents want students to learn how to effectively make decisions concerning their future. With this increased emphasis comes the need to evaluate current career education programs which is why this study is significant and useful. The central findings were as follows: first, as a result of taking a career planning course students did increase their career maturity. Second, current career education planning curriculum was similar to the proposed course of study for career planning which comes into effect in September 1999. Current curriculum does help to prepare students to make informed educational and career decisions, a chief aim of the proposed curriculum. Knowing that this outcome is currently achieved will help when the course is being organized to fit the new curriculum.
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The relative ease to concentrate and purify adenoviruses, their well characterized mid-sized genome, and the ability to delete non-essential regions from their genome to accommodate foreign gene, made adenoviruses a suitable candidate for the construction of vectors. The use of adenoviral vectors in gene therapy, vaccination, and as a general vector system for expressing foreign genes have been documented for some time. In this study, the objective was to rescue a BAV3 E1 or E3 recombinant vector carrying the kanamycin resistant gene, a dominant selectable marker with useful applications in studying vectored gene expression in mammalian cells. To accomplish the objective of this study, more information about BAV3 DNA sequences was required in order to make the manipulation of the virus genome accessible. Therefore, sequencing of the BAV3 genome from 1 1 .7% to 30.8% was carried out. Analysis of the determined sequences revealed the primary structure of important viral gene products coded by E2 including BAV3 DNA pol and precursor to terminal protein. Comparative analysis of these proteins with their counterparts from human and non human adenoviruses revealed important insights as to the evolutionary lineage of BAV3. In order to insert the kanamycin resistance gene in either E1 or E3, it was necessary to delete BAV3 sequences to accommodate the foreign gene so as not to exceed the limit of the packaging capacity of the virus. To construct a recombinant BAV3 in which a foreign gene was inserted in the deleted E1 region, an E1 shuttle vector was constructed. This involved the deletion from the viral sequences a region between 1.3% to 9% and inserting the kanamycin resistance gene to replace the deletion. The E1 shuttle vector contained the left (0%- 53.9%) segment of the genome and was expected to generate BAV3 recombinants that can be grown and propagated in cells that can complement the missing E1 functions. To construct a similar shuttle vector for E3 deletion, DNA sequences extending from 78.9% to 82.5% (1281 bp) were deleted from within the E3 region that had been cloned into a plasmid vector. The deleted region corresponds to those that have been shown to be non-essential for viral replication in cell culture. The resulting plasmid was used to construct another recombinant plasmid with BAV3 DNA sequences extending from 37.1% to 100% and with a deletion of E3 sequences that were replaced by kanamycin resistance gene. This shuttle plasmid was used in cotransfections with digested viral DNA in an attempt to rescue a recombinant BAV3 carrying the kanamycin resistance gene to replace the deleted E3. In spite of repeated attempts of transfection, El or E3 recombinant BAV3 were not isolated. It seems that other approaches should be applied to make a final conclusion on BAV3 infectivity.
Resumo:
Palynomorphs from two siliciclastic margins were examined to gain insights into continental margin architecture. Sea level change is thought to be one of the primary controls on continental margin architecture. Because Late Neogene glacioeustasy has been well studied marine sediments deposited during the Late Neogene were examined to test this concept. Cores from the outer shelf and upper slope were taken from the New Jersey margin in the western North Atlantic Ocean and from the Sunda Shelf margin in the South China Sea. Continental margin architecture is often described in a sequence stratigraphic context. One of the main goals of both coring projects was to test the theoretical sequence stratigraphic models developed by a research group at Exxon (e.g. Wilgus et al., 1988). Palynomorphs provide one of the few methods of inferring continental margin architecture in monotonous, siliciclastic marine sediments where calcareous sediments are rare (e.g. New Jersey margin). In this study theoretical models of the palynological signature expected in sediment packages deposited during the various increments of a glacioeustatic cycle were designed. These models were based on the modem palynomorph trends and taphonomic factors thought to control palynomorph distribution. Both terrestrial (pollen and spores) and marine (dinocysts) palynomorphs were examined. The palynological model was then compared with New Jersey margin and Sunda Shelf margin sediments. The predicted palynological trends provided a means of identifying a complete cycle of glacioeustatic change (Oxygen Isotope Stage 5e to present) in the uppermost 80 meters of sediment on the slope at the New Jersey margin. Sediment availability, not sea meters of sediment on the slope at the New Jersey margin. Sediment availability, not sea level change, is thought to be the major factor controlling margin architecture during the late Pleistocene here at the upper slope. This is likely a function of the glacial scouring of the continents which significantly increases sediment availability during glacial stages. The subaerially exposed continental shelf during the lowstand periods would have been subject to significant amounts of erosion fi:om the proglacial rivers flowing fi-om the southern regions of the ice-sheet. The slope site is non-depositional today and was also non-depositional during the last full interglacial period. The palynomorph data obtained fi-om the South China Sea indicate that the major difference between the New Jersey Margin sites and the Sunda Shelf margin sites is the variation in sediment supply and the rate of sediment accumulation. There was significantly less variation in sediment supply between glacial and interglacial periods and less overall sediment accumulation at the Sunda Shelf margin. The data presented here indicate that under certain conditions the theoretical palynological models allow the identification of individual sequence stratigraphic units and therefore, allow inferences regarding continental margin architecture. The major condition required in this approach is that a complete and reliable database of the contemporaneous palynomorphs be available.
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The work to be presented herein illustrates several important facts. First, the synthesis of BIBOL (19), a 1,4-diol derived from the monoterpene camphor has allowed us to demonstrate that oxidative dimerizations of enolates can, and do proceed with nearly complete diastereoselectivity under kinetically controlled conditions. The yield of BIBOL is now 50% on average, with a 10% yield of a second diastereomer, which is likely the result of a non-kinetic hydride reduction, thereby affording the epimeric alcohol, 20, coupled on the exo face of camphor. This implies the production of 60% of a single coupling diastereomer. No other diastereomers from the reduction were observed. The utility of BEBOL has been illustrated in early asymmetric additions of diethylzinc to aryl aldehydes, with e.e.'s as high as 25-30%. '^' To further the oxidative coupling work, the same methodology which gave rise to BIBOL was applied to the chiral pool ketone, menthone. Interestingly, this gave an excellent yield of the a-halohydrin (31), which is the result of a chlorination of menthone. This result clearly indicates the high stereoselectivity of the process regardless of the outcome, and has illustrated an interesting dichotomy between camphor and menthone. The utility of the chlorination product as a precursor other chiral ligands is currently being investigated. > ' Finally, a new series of 1,3-diols as well as a new aminoalcohol have successfully been synthesized from highly diastereoselective aldol/mannich reactions. Early studies have indicated their potential in asymmetric catalysis, while employing pi-stack interactions as a means of controlling enantioselective aldol reactions.
Resumo:
This study sought to explore the changing nature of the financial services industry in Toronto, Canada and the impact that these changes will have on the vocational educational outcomes required by Ontario Colleges of Applied Arts and Technology (CAAT) graduates who wish to enter the financial services industry. The study was descriptive and exploratory, based on both quantitative and qualitative data. Triangulation of 3 data sources (a collection of newspaper articles from the Toronto Star between July 1999 and June 2000, the calendars of the 25 CAATs, and a survey questionnaire prepared by me and distributed to subject matter experts who are key practitioners in the financial services industry) was used. The study contains a discussion of how the financial services industry is changing. The first question to be answered was: What do current practitioners in financial services perceive to be the knowledge, skills, and attitudes that will be required of future graduates for employment within the financial services industry? The study found that Ontario CAAT's graduates entering the financial services field need both business and financial services vocational learning outcomes. Colleges should have 2 programs 1 in accounting and 1 in financial services. The report addresses which specific topics should be included in the financial services program. The second question to be answered was: How does this anticipated profile of knowledge, skills, and attitudes change depending on the degree of implementation of the new technologies by the survey respondent? The study found no pattern. The third question to be answered was: In what way do existing programs need to change in the area of accreditation as perceived by the respondents? The study found that for accreditation, 3 credentials should be addressed within the financial services program. These are the Canadian Securities, the Life Underwriters, and the Certified Financial Planner designations. The last question to be answered was: What new knowledge, skills, and attitudes need to be incorporated into college curricula to address changing needs in the employment sector? For each Ontario CAAT which has a financial services program (excluding accounting), their program was reviewed in light of the topics as perceived by professionals in the financial services industry.
Resumo:
My research permitted me to reexamine my recent evaluations of the Leaf Project given to the Foundation Year students during the fall semester of 1997. My personal description of the drawing curriculum formed part of the matrix of the Foundation Core Studies at the Ontario College of Art and Design. Research was based on the random selection of 1 8 students distributed over six of my teaching groups. The entire process included a representation of all grade levels. The intent of the research was to provide a pattern of alternative insights that could provide a more meaningful method of evaluation for visual learners in an art education setting. Visual methods of learning are indeed complex and involve the interplay of many sensory modalities of input. Using a qualitative method of research analysis, a series of queries were proposed into a structured matrix grid for seeking out possible and emerging patterns of learning. The grid provided for interrelated visual and linguistic analysis with emphasis in reflection and interconnectedness. Sensory-based modes of learning are currently being studied and discussed amongst educators as alternative approaches to learning. As patterns emerged from the research, it became apparent that a paradigm for evaluation would have to be a progressive profile of the learning that would take into account many of the different and evolving learning processes of the individual. A broader review of the student's entire development within the Foundation Year Program would have to have a shared evaluation through a cross section of representative faculty in the program. The results from the research were never intended to be conclusive. We realized from the start that sensory-based learning is a difficult process to evaluate from traditional standards used in education. The potential of such a process of inquiry permits the researcher to ask for a set of queries that might provide for a deeper form of evaluation unique to the students and their related learning environment. Only in this context can qualitative methods be used to profile their learning experiences in an expressive and meaningful manner.
Resumo:
ABSTRACT Recombinant adenoviruses are currently under intense investigation as potential gene delivery and gene expression vectors with applications in human and veterinary medicine. As part of our efforts to develop a bovine adenovirus type 2 (BAV2) based vector system, the nucleotide sequence of BAV2 was determined. Sixty-six open reading frames (ORFs) were found with the potential to encode polypeptides that were at least 50 amino acid (aa) residue long. Thirty-one of the BAV2 polypeptide sequences were found to share homology to already identified adenovirus proteins. The arrangement of the genes revealed that the BAV2 genomic organization closely resembles that of well-characterized human adenoviruses. In the course of this study, continuous propagation of BAV2 over many generations in cell culture resulted in the isolation of a BAV2 spontaneous mutant in which the E3 region was deleted. Restriction enzyme, sequencing and PCR analyses produced concordant results that precisely located the deletion and revealed that its size was exactly 1299 bp. The E3-deleted virus was plaque-purified and further propagated in cell culture. It appeared that the replication of such a virus lacking a portion of the E3 region was not affected, at least in cell culture. Attempts to rescue a recombinant BAV2 virus with the bacterial kanamycin resistance gene in the E3 region yielded a candidate as verified with extensive Southern blotting and PCR analyses. Attempts to purify the recombinant virus were not successful, suggesting that such recombinant BAV2 was helper-dependent. Ten clones containing full-length BAV2 genomes in a pWE15 cosmid vector were constructed. The infectivity of these constructs was tested by using different transfection methods. The BAV2 genomic clones did appear to be infectious only after extended incubation period. This may be due to limitations of various transfection methods tested, or biological differences between virus- and E. co//-derived BAV2 DNA.
Resumo:
This cross-case study explored the extent to which two fitness facilities were accommodating diversity with respect to age, ethnicity, gender, social class, sex-role socialization, and persons with a disability among both members and staflf. The sites were purposely chosen in a large city and a smaller city in order to provide as representative an example as possible of health clubs within a small sample population. The interview participants were selected by a combination of stratified, typical case, and snowball sampling strategies. . , .. , The intent of the exploration was a two-fold examination of diversity issues within both the membership and the staff of the organization. Data were collected and analysis was done using a triangulation method involving personal interviews, observations, and facility documentation. The results ofthe study showed that the members and staff at each facility were rather homogeneous in ethnicity, age, social class, physical ability, and physical appearance. From a membership standpoint, the environment of the sites presented the impression of being affordable only to the middle- and upper-middle classes, unwelcoming to the older, less fit, or overweight participant, economically exclusive for youth, and nonaccommodating for people with a disability. With respect to staff, the findings indicated that the fitness facilities purported to be team-oriented in theory, but were hierarchical in practice, with the major decision making being made by the male executives. The paper concludes with the recommendation that students must be given a practical toolkit for dealing with these issues in their postsecondary courses.
Resumo:
Gamma-aminobutyric acid (GAB A) is a ubiquitous non-protein amino acid synthesized via the decarboxylation of L-glutamate in a reaction catalyzed by the cytosolic enzyme L-glutamate decarboxylase (GAD). In animals it functions as an inhibitory neurotransmitter. In plants it accumulates rapidly in response to various stresses, but its function remains unclear. The hypothesis that GABA accumulation in leaf tissue may function as a plant resistance mechanism against phytophagous insect activity was investigated. GABA accumulation in response to mechanical stimulation, mechanical damage and insect activity was demonstrated. In wt tobacco (Nicotiana tabacum cv Samsun), mechanical stimulation or damage caused GABA to accumulate within 2 min from mean levels of 14 to 37 and 1~9 nmol g-l fresh weight (FW), respectively. In the transgenic tobacco strain CaMVGAD27c overexpressing Petunia GAD, the same treatments caused GABA to accumulate from 12 to 59 and 279 nmol g-l FW, respectively. In the transgenic tobacco strain CaMVGADilC 11 overexpressing Petunia GAD lacking an autoinhibitory domain, mechanical stimulation or damage caused GABA to accumulate from 180 to 309 and 630 nmol g-l FW, respectively. Ambulatory activity by tobacco budworm (TBW) larvae (Heliothis virescens) on leaves of CaMVGAD27c tobacco caused GABA to accumulate from 28 to 80 nmol g-l FW within 5 min. Ambulatory and leaf-rolling activity by oblique banded leaf roller (OBLR) larvae (Choristoneura rosaceana cv Harris) on wt soybean leaves (Glycine max cv Harovinton) caused GABA to accumulate from 60 to 1123 nmol g-l FW within 20 min. Increased GABA levels in leaf tissue were shown to affect phytophagous preference in TBW larvae presented with wt and transgenic tobacco leaves. When presented with leaves of Samsun wt and CaMVGAD27c plants, TBW larvae consumed more wt leaf tissue (640 ± 501 S.D. mm2 ) than transgenic leaf tissue (278 ± 338 S.D. mm2 ) nine times out of ten. When presented with leaves of Samsun wt and CaMVGAD~C11 plants, TBW larvae consumed more transgenic leaf tissue (1219 ± 1009 S.D. mm2 ) than wt leaf tissue (28 ± 31 S.D. mm2 ) ten times out of ten. These results indicate that: (1) ambulatory activity of insect larvae on leaves results in increased GABA levels, (2) transgenic tobacco leaves with increased capacity for GABA synthesis deter feeding, and (3) transgenic tobacco leaves with constitutively higher GABA levels stimulate feeding.
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Despite the increasing public profile of lesbian childbearing, public health resources for expectant women often bear heterosexist assumptions and create barriers to accessing information relevant to lesbian mothering experiences. This descriptive, exploratory study examined one lesbian couple's perceived educational needs for effective support, barriers to access, strategies for locating care, and the impact of childbearing on their lives, as well as their reflections on inviting ways to offer supportive practices in a public health context. A case study approach used feminist ethnographic methodology and purposeful convenience sampling. A prenatal and a postnatal open-ended interview were completed with 1 white, middle-class, able, lesbian childbearing couple, each ofwhom has birthed as coparent and biological mother in this couple relationship. Despite this couple's immense situated privilege, they struggled to locate the support they sought for childbearing in a way that offered optimal emotional and physical care from the preconceptual to postpartum stages and which maintained confidentiality or anonymity as desired. They created meaningful care through personal networks. The findings were framed using invitational and feminist theories: how people, places, programs, processes, policies, and politics contributed to educational support. A three part conceptual framework emerged which identified components of access to support: perceived safety of resources, disclosure status, situated privilege, and public or private availability of information. The consequences of lack of public access to comprehensive childbearing care for lesbian women and their communities are described. Educational possibilities addressed systemic heterosexism through the development of sensitive educators, meaningful curriculum, program planning, explicit policies, community partnerships, and political leadership with respect to both institutional and research venues.
Resumo:
The purpose of this study was to determine the effect that calculators have on the attitudes and numerical problem-solving skills of primary students. The sample used for this research was one of convenience. The sample consisted of two grade 3 classes within the York Region District School Board. The students in the experimental group used calculators for this problem-solving unit. The students in the control group completed the same numerical problem-solving unit without the use of calculators. The pretest-posttest control group design was used for this study. All students involved in this study completed a computational pretest and an attitude pretest. At the end of the study, the students completed a computational posttest. Five students from the experimental group and five students from the control group received their posttests in the form of a taped interview. At the end of the unit, all students completed the attitude scale that they had received before the numerical problem-solving unit once again. Data for qualitative analysis included anecdotal observations, journal entries, and transcribed interviews. The constant comparative method was used to analyze the qualitative data. A t test was also performed on the data to determine whether there were changes in test and attitude scores between the control and experimental group. Overall, the findings of this study support the hypothesis that calculators improve the attitudes of primary students toward mathematics. Also, there is some evidence to suggest that calculators improve the computational skills of grade 3 students.
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The frequency and type of agonistic displays involved in male-male encounters should be significantly influenced by the presence of females. Discrete agonistic displays vary in energy expenditure and risk, and therefore should be dependent on available resources. The influence of live females and the scent of females, on the frequency of male agonistic displays was observed in a laboratory terrarium using the field cricket Gryllus bimaculatus. The effect of energy constraints on display frequency was also determined. Half the males were fed a diet high in protein and fet; the other males were fed a lower quality diet, for a 7-11 day period. The frequency of five individual displays and mating frequency were recorded using an Event Recorder and notebook. Each group of males was presented with three experimental conditions, over three days, involving the presence or absence of live females and female scent. The presence of females elicited an increase in all displays except antennation; female scent increased the frequency of antennations, mandible flares and grapples, but to a lesser extent than did live females. The frequency of grapples significantly increased for males fed the high quality diet; however diet did not influence the other displays. The combined influence of diet and condition was significant for mandible flare only. Mating frequency was not influenced by diet. However, the frequency ofthe displays were positively correlated with mating frequency for high quality fed males. Escalated displays involving high costs, such as grapple and mandible flare, increased in frequency when the benefits of winning contests were high in G.bimaculatus. Escalation to grapple behaviour was less evident for males fed the lower quality diet as this imposed energy constraints on high cost displays.