The purpose of this study was to determine if selected variables were significant predictors for the academic success or failure of Algebra I students. Two methods of data gathering were used in the study. The Student Attribution Inventory (SAI) was first administered to the classes during one class period. One hundred eighty-five students participated. Only two students could not because of a language barrier. The second method of data gathering was done by the researcher. First, a letter was sent home to the students' parents for permission to use the cumulative folders of their sons and daughters. Letters were collected daily by the teacher and weekly by the researcher. A follow-up letter was sent home several weeks later to those parents who had not previously responded. Once permission was granted, the researcher received the cumulative folders and obtained the necessary information. Out of 185 students, 110 were used in the study. Stepwise multiple regression was used for four of the eight hypotheses. These were tested at the .05 level of significance. This level of prediction was used to determine if selected variables were significant predictors for the academic success or failure of Algebra I students. The findings showed that achievement motivation (a resultant behavior of an emotional conflict between hopes for success and fears of failure), luck (external, unstable, unintentional factor which is related to the perceived randomness in events), and previous mathematics achievement (as measured by the California Achievement Test (CAT)), were the variables found to be statistically significant. Ability, previous reading achievement, and age were not entered into the regression equation by the Statistical Package for the Social Sciences (SPSS) because of insufficient predictability. The remaining hypotheses employed t-tests as the statistical method of testing. These four hypotheses were also tested at the .05 level of significance. The results showed that neither sex differences nor ethnic groups were significant in prediction of Algebra I final grades and achievement motivation. Further research is necessary to increase the understanding of achievement motivation and luck in classroom situations, counseling sessions, and group dynamics.

Continuous control of two languages during speech production may result in a ‘bilingual advantage’, where highly proficient bilinguals outperform monolinguals on nonverbal cognitive tasks. Greater linguistic distance between two bilingual languages is expected to influence this relationship, where bilinguals who engage with similar languages develop enhanced inhibitory control. To address this issue, this study examined reaction times and correct response rates on the attentional network task (ANT) and the Simon Task, where three different attentional networks (alerting, orienting and executive control) were examined. Two bilingual groups (English-German and English-Chinese) and one monolingual group (English) completed these attentional tasks as well as a Language Experience and Proficiency Questionnaire (LEAP-Q). Results did not provide unequivocal support for the ‘bilingual advantage’ hypothesis, which was only demonstrated by superior performance of bilinguals on the congruent and incongruent trials of the Simon Task. The Simon effect did not differ significantly between bilingual and monolingual participants, and no significant differences were revealed by performance on the ANT. The findings of this study also suggest that the effects of linguistic distance on cognitive functioning may not be quantitative in nature and should be investigated using neuroimaging techniques.

As a first generation of compounds, the nucleosides adenosine 8, cytidine 11, guanosine 9, inosine 116 and uridine 12, as well as the sugar ᴅ-(-)-ribose 100, were transformed into the corresponding 5’-O-(tert-butyldiphenylsilyl)- and 5’-O-(4,4’-dimethoxytrityl)-derivatives. These were subsequently protected as acetyl, benzoyl and allyl derivatives at various positions on the molecules, to give a range of twenty five unique compounds for biological testing. The nucleoside and corresponding ᴅ-(-)-ribose derivatives were evaluated for their antibacterial activity against two Gram-positive (Staphylococcus aureus ATCC 25923 and Bacillus cereus DL5) and two Gram-negative bacteria (Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922), for their anti-HIV activity against strain HLTVIIIB as well as for their anticancer properties, by evaluating inhibition of cell proliferation in two adherent (HT-29 and Caco-2) and three suspension (HL-60, Jurkat and K-562) cell lines. From these screens, and based on the 2,3,5-triphenyltetrazolium chloride (TTC) assay, it was found that 5’-O-(tert-butyldiphenylsilyl)uridine 107, 5’-O-(tert-butyldiphenylsilyl)-1'-O-methoxy-ᴅ-(-)-ribose 102 and tert-butyldiphenylsilyl alcohol 145 exhibited antimicrobial activity towards only the Gram-positive bacteria when compared to the ciprofloxacin 153 control. None of the compounds tested showed any antiviral activity when assayed against HIV; however, all compounds indicated some form of toxicity to the uninfected cells. Subsequent cell proliferation studies indicated pronounced activity against both the adherent and suspension cancer cell lines for 5’-O-(tert-butyldiphenylsilyl)uridine 107, 5’-O-(tert-butyldiphenylsilyl)cytidine 134, tert-butyldiphenylsilyl alcohol 145, 5’-O-(4,4’-dimethoxytrityl)uridine 126 and 4,4’-dimethoxytrityl alcohol 147. Our initial screen indicated that ᴅ-(-)-ribose derivatives do not show any significant general biological activity; whereas (tert-butyldiphenylsilyl)-protected nucleoside derivatives and the corresponding tert-butyldiphenylsilyl alcohol control are intrinsically more bio-active. From the data reported for the anti-bacterial and the cell proliferation studies, we concluded that the nucleoside showing the most promising results was uridine 12 and our mini structure- activity study on the uridine derivatives found that the best position for performing modifications to the nucleoside was at the 5'-OH position on the sugar ring. As such, this would become the initial focus for the synthesis of the second generation compounds. The second generation compounds included a series of ten uridine 12 and five 5-methyluridine 233 derivatives which were protected on the primary alcohol with a range of different silicon-containing protecting groups. At the same time, we used a general procedure to synthesize a series of fourteen silanols for use as control compounds. The uridine 12, 5-methyluridine 233 and corresponding silanol derivatives were screened for their antibacterial activity against the same two Gram-positive and two Gram-negative bacteria as above, as well as for their anticancer properties, by evaluating inhibition of cell proliferation in a series of six adherent cell lines (five human: Hs683, MCF-7, PC-3, SKMEL-28, U373, and one murine: B16F10) cell lines. The data obtained for our TTC assay showed that converting the base in 1-[(6aR,8R,9R,9aS)-9-hydroxy-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,-2,4]trioxadisilocin-8-yl]-pyrimidine-2,4(1H,-3H)dione 234 to the 5-methyl derivative 254 caused a corresponding loss in antibacterial activity for the compound, whereas oxidising the secondary alcohol on the 2'-position of the sugar ring to give compound 239 caused a corresponding increase in antibacterial activity. As such, we concluded that 1-[(6aR,8R,9aR)-2,2,4,4-tetraisopropyl-9-oxotetrahydro-6H-furo[3,2-f][1,3,5,-2,4]trioxadisilo-cin-8-yl]pyrimidine-2,4(1H,3H)dione 239 was the compound with the best antibacterial activity out all of the first and second generations of nucleoside derivatives assayed. The results obtained in the TTC assay, were supported by our scanning electron (SEM) and confocal scanning electron (CSLM) microscopy studies. Interestingly, the CSLM study suggests that the synthetic compound 239 is bacteriocidal and is inactivating cells, not simply inhibiting their growth. From the inhibition of cell proliferation assay performed on the fifty combined first and second generation derivatives and their corresponding controls, we found that the six most active compounds (5'-O-(tert-butyldiphenylsilyl)adenosine 142, 5'-O-(tert-butyldiphenyl-silyl)cytidine 134, 5'-O-(tert-butyldiphenylsilyl)uridine 107, 2',3'-O-diacetyl-5'-O-(tert-butyl-diphenylsilyl)uridine 123, 2',3'-O-diacetyl-5'-O-(4,4'-dimethoxytrityl)uridine 127 and 3-benzoyl-1-[(6aR,8R,9R,9aS)-9-hydroxy-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,-5,2,4]trioxa-disilocin-8-yl]pyrimidine-2,4(1H,3H)-dione 235) had mean IC50 values of approximately 24-28 μM.

by Lee Fong Lok. / Chinese title: / Bibliography: leaves 103-111 / Thesis (M.A.Ed.)--Chinese University of Hong Kong

There is no abstract available for this thesis.

In Western countries, there are around 8-10% of school age children suffering from mild to moderate reading difficulties. Similarly, in Hong Kong the prevalence of reading difficulties among school age children was found to be 9.7- 12%. An understanding of the mechanisms involved in reading helps us to determine the skills necessary for successful reading. The Phonological Mediation Hypothesis (PMH), which claims that phonological recoding is a necessary phase during lexical access, is widely known for its postulation that phonological awareness would be a significant prognostic indicator of reading development. Theoretically, individuals who have difficulties in phonological recoding during lexical access should also encounter reading difficulties. Good readers with hearing impairment are, therefore, considered as counter examples of PMH. If the above prediction of PHM is true, skilled readers with hearing impairment should have the ability to develop an intact phonological representation and hence are more capable of phonological recoding. In this study, the reading behaviors of children with hearing impairment (HI), that of their reading level matched (RL) and that of their chronological age matched (CA) controls were compared in three tasks—an auditory perceptual task of onset rime awareness (TAPOR); a synonym decision task (SDT); and a homophone decision task (HDT). The results for TAPOR showed that auditory perceptual ability (APOR) accounted for 49% of the variance in the reading ability of children with hearing impairment. In addition, results of cross group comparisons on the scores in TAPOR demonstrated a possible causal relationship between APOR and reading ability in subjects with hearing impairment. On the other hand, SDT and HDT results indicated a significant preference for orthographic foils in RL and HI subjects with low reading ability. An increasing tendency to choose synonyms or homophones, and a decreasing tendency to use orthographic distractors was observed across subject groups with Primary 1, Primary 2 and Primary 6 reading abilities. A similar but delayed pattern of change in preference for distractors was observed in HI subjects. The results only partially agree with PMH. An alternative hypothesis—the Psycholinguistic Grain Size Theory (PGST) — might be a better model to explain the observed results. With reference to the results of TAPOR, the correlation between reading ability and auditory perceptual ability could be explained in terms of the ‘availability problem’ postulated in this latter model. In the same way, the early emergence of orthographic effect in almost all subjects except CA controls and the late emergence of a number of reading strategies operating at different levels of grain size can be better explained by ‘consistency problems’ and ‘granularity problems’ proposed in PGST. These findings are considered, and directions for further studies are outlined. / published_or_final_version / Speech and Hearing Sciences / Master / Master of Philosophy

Generally, females are regarded as the group who has better verbal and reading abilities (Maccoby & Jacklin, 1974; Denno, 1982), although there are still some disagreements on particular aspects or language systems (Hyde & Linn, 1988; Hetherington & Parke, 1986). We asked whether gender differences of reading ability exist in Chinese children and if so, how the difference may be demonstrated. In addition, we investigated whether the development of reading ability follows a hierarchical model (Gough &Hillinger, 1980; Ehri, 1980; Ehri & Wilce, 1985), according to which, the gender differences may vary with age and reading experience. We tested children’s character reading ability and phonological awareness in a Shandong primary school. Fifty-five second graders and forty-three fourth graders performed behavioral tasks containing a Chinese character reading test, a Chinese onset-rime oddity test and an English onset-rime oddity test. We found that Chinese children exhibited a significant gender difference in Chinese character reading ability. However, we have not found gender differences on onset-rime level phonological awareness. Thus, gender differences of reading ability exist in Chinese children, even if the differences only cover partial phonological or orthographic skills. The present data have also yielded the predicted result that the development of gender differences change with age and reading experience. Specifically, the gender difference on Chinese character reading ability emerged after Grade 2. In terms of the onset-rime oddity task, the performances of boys and girls showed no striking difference at any grades. These results reveal that gender differences of reading ability exist in Chinese children, especially in children in higher grades (Grade 4). Different types of verbal skills and learning attitude should be taken into account, and be examined in the future. / published_or_final_version / Linguistics / Master / Master of Arts

abstract / Education / Doctoral / Doctor of Philosophy

No description available.

No description available.