11 resultados para Phonological and orthographic overlap

em Brock University, Canada


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Over the past decade, research has suggested that phonological and word awareness skills (i.e., the ability to reflect on and manipulate the components of language) are important for early reading acquisition. This study examined the phonological and word awareness skills of language-delayed kindergarten children at the beginning and end of a language intervention program using five tasks. The results were compared to the performances of average kindergarten children who did not participate in the language intervention program. There were significant performance differences for all tasks, favouring the average children, at the beginning of the intervention program. However, at the end of the training interval, the languagedelayed children performed as well as the average children.

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Research into the evolutionary origins of sociality in insect colonies is changing emphasis from understanding how eusociality is maintained to how insects transition from solitary to social lifestyles. The pygmy carpenter bees (Ceratina spp.) offer an excellent model for investigating such factors as they have been historically thought of as solitary but have recently been shown to be socially polymorphic, which may indicate that they are currently in a transitive phase. By utilizing behavioural observation and experimental removal protocols, I show that extended parental care, as well as sibling care in Ceratina calcarata plays an important role in offspring development. I found, upon removal of the mother, that specifically produced ‘dwarf’ female offspring take over parental care roles in the nest. The existence of alloparental care and generational overlap suggests that although they are classified as solitary bees, C. calcarata possess the prerequisite behavioural repertoire for sociality.

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This study examined the effectiveness of a 9-week reading program in improving the phonological awareness (PA) skills of a seven year old boy with Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD), and Oppositional Defiant Disorder (ODD). The study’s secondary goal was to describe how the participant engaged with and enjoyed the HeadSprout computer program. The participant attended a one hour reading program incorporating 30 minutes of HeadSprout Early Reading three days a week for 9 weeks. Results demonstrated that the participant’s PA scores increased from the 16th percentile at pre-test to the 35th percentile post program. Four of five measures of PA increased, segmenting nonwords decreased to the 2nd percentile post program. Momentary time sampling procedures revealed the participant was engaged with the computer program 94.5% of the time. Perceived ratings of enjoyment indicated the participant enjoyed using the program. Specific components of the program which may have influenced participant enjoyment and engagement are discussed. Study limitations and implications of these findings are discussed in reference to future research.

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All-electron partitioning of wave functions into products ^core^vai of core and valence parts in orbital space results in the loss of core-valence antisymmetry, uncorrelation of motion of core and valence electrons, and core-valence overlap. These effects are studied with the variational Monte Carlo method using appropriately designed wave functions for the first-row atoms and positive ions. It is shown that the loss of antisymmetry with respect to interchange of core and valence electrons is a dominant effect which increases rapidly through the row, while the effect of core-valence uncorrelation is generally smaller. Orthogonality of the core and valence parts partially substitutes the exclusion principle and is absolutely necessary for meaningful calculations with partitioned wave functions. Core-valence overlap may lead to nonsensical values of the total energy. It has been found that even relatively crude core-valence partitioned wave functions generally can estimate ionization potentials with better accuracy than that of the traditional, non-partitioned ones, provided that they achieve maximum separation (independence) of core and valence shells accompanied by high internal flexibility of ^core and Wvai- Our best core-valence partitioned wave function of that kind estimates the IP's with an accuracy comparable to the most accurate theoretical determinations in the literature.

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The mechanism whereby cytochrome £ oxidase catalyses elec-. tron transfer from cytochrome £ to oxygen remains an unsolved problem. Polarographic and spectrophotometric activity measurements of purified, particulate and soluble forms of beef heart mitochondrial cytochrome c oxidase presented in this thesis confirm the following characteristics of the steady-state kinetics with respect to cytochrome £: (1) oxidation of ferrocytochrome c is first order under all conditions. -(2) The relationship between sustrate concentration and velocity is of the Michaelis-Menten type over a limited range of substrate. concentrations at high ionic strength. (3) ~he reaction rate is independent from oxygen concentration until very low levels of oxygen. (4) "Biphasic" kinetic plots of enzyme activity as a function of substrate concentration are found when the range of cytochrome c concentrations is extended; the biphasicity ~ is more apparent in low ionic strength buffer. These results imply two binding sites for cytochrome £ on the oxidase; one of high affinity and one of low affinity with Km values of 1.0 pM and 3.0 pM, respectively, under low ionic strength conditions. (5) Inhibition of the enzymic rate by azide is non-c~mpetitive with respect to cytochrome £ under all conditions indicating an internal electron transfer step, and not binding or dissociation of £ from the enzyme is rate limiting. The "tight" binding of cytochrome '£ to cytochrome c oxidase is confirmed in column chromatographic experiments. The complex has a cytochrome £:oxidase ratio of 1.0 and is dissociated in media of high ionic strength. Stopped-flow spectrophotometric studies of the reduction of equimolar mixtures and complexes of cytochrome c and the oxidase were initiated in an attempt to assess the functional relevance of such a complex. Two alternative routes -for reduction of the oxidase, under conditions where the predominant species is the £ - aa3 complex, are postulated; (i) electron transfer via tightly bound cytochrome £, (ii) electron transfer via a small population of free cytochrome c interacting at the "loose" binding site implied from kinetic studies. It is impossible to conclude, based on the results obtained, which path is responsible for the reduction of cytochrome a. The rate of reduction by various reductants of free cytochrome £ in high and low ionic strength and of cytochrome £ electrostatically bound to cytochrome oxidase was investigated. Ascorbate, a negatively charged reagent, reduces free cytochrome £ with a rate constant dependent on ionic strength, whereas neutral reagents TMPD and DAD were relatively unaffected by ionic strength in their reduction of cytochrome c. The zwitterion cysteine behaved similarly to uncharged reductants DAD and TI~PD in exhibiting only a marginal response to ionic strength. Ascorbate reduces bound cytochrome £ only slowly, but DAD and TMPD reduce bound cytochrome £ rapidly. Reduction of cytochrome £ by DAD and TMPD in the £ - aa3 complex was enhanced lO-fold over DAD reduction of free £ and 4-fold over TMPD reduction of free c. Thus, the importance of ionic strength on the reactivity of cytochrome £ was observed with the general conclusion being that on the cytochrome £ molecule areas for anion (ie. phosphate) binding, ascorbate reduction and complexation to the oxidase overlap. The increased reducibility for bound cytochrome £ by reductants DAD and TMPD supports a suggested conformational change of electrostatically bound c compare.d to free .£. In addition, analysis of electron distribution between cytochromes £ and a in the complex suggest that the midpotential of cytochrome ~ changes with the redox state of the oxidase. Such evidence supports models of the oxidase which suggest interactions within the enzyme (or c - enzyme complex) result in altered midpoint potentials of the redox centers.

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TITLE: The normal co-ordinate analysis, vibrational spectra and theoretical infrared intensities of some thiocarbonyl halides. AUTHOR: J. L. Brema SUPERVISOR: Dr. D. C. Moule NUMBER OF PAGES: 89 ABSTRACT: The vibrational assignment of the five-in-plane fundamental modes of CSClBr has been made on the basis of infrared gas phase and liquid Raman spectral analyses to supplement our earlier vibrational studies. Even though the one out-of-plane fundamental was not observed spectroscopically an attempt has been made to predict its frequency. The vibrational spectra contained impurity bands and the CSClBr assignment was made only after a thorough analysis of the impurities themselves. A normal co-ordinate analysis calculation was performed assuming a Urey-Bradley force field. This calculation yielded the fundamental frequencies in good agreement with those observed after refinement of the originally transferred force constants. The theoretical frequencies are the eigenvalues of the secular equation and the calculation also gave the corresponding eigenvectors in the form of the very important LLj matrix. The [l] matrix is the transfoirmation between internal co-ordinates and normal co-ordinates and it is essential for Franck-Condon calculations on electronically excited molecules and for infrared Integrated band intensity studies. Using a self-consistent molecular orbital calculation termed "complete neglect of differential overlap" (CNDO/2) , theoretical values of equilibrium bond lengths and angleswere calcuted for a series of carbonyl and thlocarbonyl molecules. From these calculations valence force field force constants were also determined but with limited success. With the CNIX)/2 method theoretical dipole moment derivatives with respect to symmetrized internal co-ordinates were calculated and the results should be useful in a correlation with experimentally determined values.

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Bovine adenovirus type 3 (BAV3) is a medium size DNA virus that causes respiratory and gastrointestinal disorders in cattle. The viral genome consists of a 35,000 base pair, linear, double-stranded DNA molecule with inverted terminal repeats and a 55 kilodalton protein covalently linked to each of the 5' ends. In this study, the viral genome was cloned in the form of subgenomic restriction fragments. Five EcoRI internal fragments spanning 3.4 to 89.0 % and two Xb a I internal fragments spanning 35.7 to 82.9 % of the viral genome were cloned into the EcoRI and Xbal sites of the bacterial vector pUC19. To generate overlap between cloned fragments, ten Hi n dIll internal fragments spanning 3.9 to 84.9 and 85.5 to 96% and two BAV3 BamHI internal fragments spanning 59.8 to 84.9% of the viral genome were cloned into the HindllI and BamHI sites of pUC19. The HindlII cloning strategy also resulted in six recombinant plasmids carrying two or more Hi ndII I fragments. These fragments provided valuable information on the linear orientation of the cloned fragments within the viral genome. Cloning of the terminal fragments required the removal of the residual peptides that remain attached to the 5' ends of the genome. This was accomplished by alkaline hydrolysis of the DNA-peptide bond. BamH I restriction fragments of the peptide-free DNA were cloned into pUC19 and resulted in two plasmids carrying the BAV3 Bam HI terminal fragments spanning 0 to 53.9% and 84.9 to 100% of the viral genome.

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This study examined the effects that a training program in phonological awareness had on the early writing skills of children in a Grade One class in the Lincoln County Separate school system. The intent of the training program was to provide consistent and systematic practice in the manipulation of the phonological structure of language. The games and activities of the training program were related to a framework of developmental phonological skills and practised in a group setting during an unstructured period of the regular classroom schedule. The training program operated three days in a six-day cycle for approximately twenty minutes a day, from November until mid-March. All children were tested at the outset and conclusion of the study to determine level of functioning in letter identification, word recognition, verbal intelligence, phonological awareness and spelling. Results of the pre-tests and post-tests were compared to determine differences between the experimental and control groups over time. In addition, a systematic analysis of the children's writing looked at the development of the spelling of regular and irregular words. The results of this study provided strong support for the hypothesis that the treatment group would progress through the stages of early writing development more quickly than children without such training. On the basis of differences between the groups over time, it was evident that training in phonological awareness had a direct positive effect on the spelling of regular words for children during the early stages of writing. The training program did not have a significant effect on the spelling of irregular words. Test results evaluating phonological awareness indicated a significant difference within each group over time but no significance between the groups during the experimental period. It would appear that the results of these tests reflect maturational changes in the child rather than causal effects of the training program. Nor did the effects of the training program transfer significantly to other aspects of language. Although some of the hypotheses considered were not supported by the study, the results do indicate that children during the early stages of writing development can benefit from a training program in phonological awareness. The theoretical direction for effective programming as a result of this study is discussed. The educational implications of training phonological awareness concurrent to beginning efforts in writing are considered.

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Sweat bees exhibit a range of social behaviours, from solitary nesting, in which no workers are produced, to strong eusociality, in which workers exhibit a high degree of altruism, behaviour that is measured by the degree of personal reproductive sacrifice. Field studies were carried out for seven weeks during May-June 2000 in southern Greece in order to investigate intraspecific social variation, and test the hypothesis of a north-south cline of decreasing eusociality in the obligately eusocial sweat bee L. (E.) malachurum. A comparative study, using principal components analysis, was performed to determine if patterns of intraspecific social variation in L. malachurum reflect the patterns of social variation within the subgenus, Evylaeus, as a whole. The results of the field study reveal that, in Greece, two worker broods were produced followed by a third brood consisting of gynes, males and some workers, indicating that there was an overlap in worker and gyne production. There was strong caste distinction between queens and workers. Workers actively foraged and participated in nest construction as most workers (58%, n=303) had a high degree of mandibular wear. Workers did not participate in the oviposition of Brood 3 gynes since only 0.7% (n=278) of workers were mated. Furthermore, queen survival until the end of Brood 3 and a substantial size differential of 10.6% between queens and workers suggested that queen domination over worker behaviour during the early to mid-part of the colony cycle was plausible. Male production in Brood 3 by some workers was likely, since the timing of worker ovarian development corresponded with the timing of male production. These findings suggest that workers of the first two broods were primarily altruistic, but some (28%) Brood 1 (9%) and Brood 2 (19%) workers produced males, indicating that the degree of altruistic behaviour declined during the lifetime of the colony. In comparison with other L. malachurum populations in Europe, the Greek population of L. malachurum had a weaker social level as a result of the higher proportion of workers potentially involved in male production, thus 3 supporting the hypothesis of a southerly cline of decreasing eusociality. Furthermore, intraspecific variation in social level across Europe appears to be due to longer breeding seasons in more southerly locations that would promote the production of larger colonies and provide opportunities for workers to evade queen control. The comparative study using principal components analysis on 20 solitary (of the subgenera Evylaeus and Lasioglossum), eusocial and socially polymorphic Evylaeus species and populations reveals that six traits are closely associated with stronger eusociality in Evylaeus. These traits are: (1) a reduction in the proportion of males in the early brood(s); (2) a reduction in the proportion of females that mate; (3) an increase in the mean number of first brood workers; (4) a reduction in the proportion of females with developed ovaries; (5) an increase in size dimorphism between castes, and (6) nest guarding. These are traits that most significantly define principal component one and therefore distinguish social type as indicated by a clear separation of the eusocial and the solitary populations, with a socially polymorphic species falling in between. Furthermore, most of these traits are under foundress control and may suggest that the evolutionary loss or gain of eusociality is based on selection pressures on a founding female. Colony size and female ovarian development are common factors distinguishing social variation in L. malachurum and within the subgenus as a whole. The principal components analysis excluding the solitary species and the socially aberrant L. marginatum populations show the L. malachurum populations separated based on an increasing proportion of workers with developed ovaries as populations are found more south, lending further support to the hypothesis of a north-south cline of decreasing eusociality.

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This mixed methods investigation examined the nutritional knowledge and habits of adolescent girls in grades 9 through 12 at a secondary school in southern Ontario. Through questionnaires, interviews, and the use of teaching and curriculum documents, this study attempted to understand whether the current nutrition curriculum is influential in developing students' nutritional knowledge, healthy eating habits, and a favourable body image. Data collection occurred over a 2-month period, involving 90 female participants, and the data analysis program SPSS was used for analysis of the quantitative questionnaire data. Interview data were organized into categories, and analysis of any emerging themes occurred. Teaching and curriculum documents were examined to determine any overlap and develop an understanding of the participants' exposure and experience within nutrition within the classroom setting. The findings of this study suggest that the current nutrition education did have an impact on the participants' nutrition knowledge. However, the impact on their eating habits and body image was limited in the context it was measured and tested. The knowledge learned within the classroom may not always be applied outside of the classroom. This study suggests that improvement in the current nutrition curriculum may be needed to have a bigger impact on adolescent females. The findings from the study shine light on areas of improvements for educators as well as development of future curriculum. Changes may need to be made not only in the specific curriculum content and expectations but also the delivery of it by the classroom teacher.

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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.