The role of phonological recoding in the reading acquisition of school children in Hong Kong

A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2005.Also available in print.Thesis (B.Sc)--University of Hong Kong, 2005.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Enantioselective Copper-Catalyzed Reductive Coupling of Alkenylazaarenes with Ketones

Catalytic enantioselective methods for the preparation of chiral azaarene-containing compounds are of high value. By combining the utility of copper hydride catalysis with the ability of C═N-containing azaarenes to activate adjacent alkenes toward nucleophilic additions, the enantioselective reductive coupling of alkenylazaarenes with ketones has been developed. The process is tolerant of a wide variety of azaarenes and ketones, and provides aromatic heterocycles bearing tertiary-alcohol-containing side chains with high levels of diastereo- and enantioselection

Severity and Progression of White Matter Changes in Frontotemporal Dementia Subtypes Using Diffusion Tensor Imaging

The three main subtypes of frontotemporal dementia (FTD): behavioural-variant FTD (bvFTD), primary progressive aphasia-nonfluent variant (nfv-PPA) and semantic variant (sv-PPA) are characterised by progressive brain atrophy in the frontotemporal regions. The brain white matter also undergoes marked pathological alterations but is less studied. This thesis aimed to study i) the patterns of white matter changes in the three FTD subtypes, ii) the progression of white matter changes in the same FTD subtypes, and iii) the white matter changes in bvFTD with or without the C9orf72 gene expansions. Chapter 3 revealed distinctive patterns of white matter changes in each FTD subtype. White matter alterations were observed in orbitofrontal and anterior temporal tracts in bvFTD, bilateral (left>right) frontotemporal tracts in nfv-PPA and circumscribed left temporal lobe in sv-PPA. These white matter changes greatly overlapped with grey matter changes in bvFTD and nfv-PPA but not in sv-PPA. The white matter abnormalities varied depending on the diffusion tensor imaging (DTI) measurements used, with mean diffusivity being the most sensitive metric for all FTD subtypes. Chapter 4 showed the 12-month longitudinal assessment of white matter changes in the same participants. White matter alterations appeared in regions shown at baseline but with additional changes extending beyond the original regions affected in all FTD subtypes. White matter abnormalities extended far beyond sites of grey matter atrophy in the same time period. Fractional anisotropy and radial diffusivity were most sensitive in detecting white matter abnormalities in this longitudinal assessment. Chapter 5 compared bvFTD cases with or without C9orf72 expansion carriers. C9orf72 expansion carriers did not exhibit the typical frontotemporal white matter changes as shown in non-carriers. Stereotypical behaviour was less prevalent in C9orf72 expansion carriers than non-carriers and the left cingulum and anterior thalamic radiation were predictive of stereotypical behavioural scores. Semantic knowledge was less affected in C9orf72 expansion carriers and the left uncinate fasciculus was predictive of changes in semantic knowledge. These predictions significantly differentiated C9orf72 expansion carriers from non-carriers. Investigations using DTI presented in this thesis improved the understanding of white matter changes in FTD and contributed to the characterisation of the different FTD subtypes

Sense-making, sensemaking and sense making:A systematic review and meta‐synthesis of literature in information science and education: An Annual Review of Information Science and Technology (ARIST) paper

Sense‐making, sensemaking, and sense making are terms used in different disciplines. Similarities of usage seem unclear. (1) to examine the concepts used in different approaches to sense‐making/sensemaking/sense making; (2) to identify, classify and synthesize recent studies relevant to information science, as well as similar group on sensemaking in education research; (3) to reflect on future directions for sense‐making/sensemaking methodology in information science. The objectives were to retrieve, examine, classify and perform meta‐synthesis on sense‐making/sensemaking studies in both information science and education research. The review used systematic review principles, with selection criteria for case studies for examination in both information science and education sets. The final meta‐synthesis used a meta‐ethnographic approach, together with findings of recent overviews on organizational sensemaking, and other information science reviews. Qualitative sense‐making studies in information science often used Dervin's SMM (sense‐making methodology) and studies in organizations and education frequently used Weick's organizational sensemaking. Different mixed methods approaches were identified. Sense‐making is actively used in research and practice in information science and knowledge management. Using a coherent sense‐making methodology helps and dialogic principles are useful in planning, data collection and analysis. Individual and collective sense‐making are important to information science

Parallel architectures for entropy coding in a dual-standard ultra-HD video encoder

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010.Includes bibliographical references (p. 97-98).The mismatch between the rapid increase in resolution requirements and the slower increase in energy capacity demand more aggressive low-power circuit design techniques to maintain battery life of hand-held multimedia devices. As the operating voltage is lowered to reduce power consumption, the maximum operating frequency of the system must also decrease while the performance requirements remain constant. To meet these performance constraints imposed by the high resolution and complex functionality of video processing systems, novel techniques for increasing throughput are explored. In particular, the entropy coding functional block faces the most stringent requirements to deliver the necessary throughput due to its highly serial nature, especially to sustain real-time encoding. This thesis proposes parallel architectures for high-performance entropy coding for high-resolution, dual-standard video encoding. To demonstrate the most aggressive techniques for achieving standard reconfigurability, two markedly different video compression standards (H.264/AVC and VC-1) are supported. Specifically, the entropy coder must process data generated from a quad full-HD (4096x2160 pixels per frame, the equivalent of four full-HD frames) video at a frame rate of 30 frames per second and perform lossless compression to generate an output bitstream. This block will be integrated into a dual-standard video encoder chip targeted for operation at 0.6V, which will be fabricated following the completion of this thesis. Parallelism, as well as other techniques applied at the syntax element or bit level, are used to achieve the overall throughput requirements. Three frames of video data are processed in parallel at the system level, and varying degrees of parallelism are employed within the entropy coding block for each standard. The VC-1 entropy encoder block encodes 735M symbols per second with a gate count of 136.6K and power consumption of 304.5 pW, and the H.264 block encodes 4.97G binary symbols per second through three-frame parallelism and a 6-bin cascaded pipelining architecture with a critical path delay of 20.05 ns.by Bonnie K. Y. Lam.S.M

Enantioselective copper-catalyzed reductive coupling of vinylazaarenes with N-Boc aldimines

The diastereo- and enantioselective reductive coupling of vinylazaarenes with N-Boc aldimines is described. The reactions proceed using chiral copper–bisphosphine complexes in the presence of TMDS as a hydride source to give reductive coupling products in moderate to high enantioselectivities

Inhalation Toxicity of Ground Lunar Dust Prepared from Apollo-14 Soil

Within the decade one or more space-faring nations intend to return humans to the moon for more in depth exploration of the lunar surface and subsurface than was conducted during the Apollo days. The lunar surface is blanketed with fine dust, much of it in the respirable size range (<10 micron). Eventually, there is likely to be a habitable base and rovers available to reach distant targets for sample acquisition. Despite designs that could minimize the entry of dust into habitats and rovers, it is reasonable to expect lunar dust to pollute both as operations progress. Apollo astronauts were exposed briefly to dust at nuisance levels, but stays of up to 6 months on the lunar surface are envisioned. Will repeated episodic exposures to lunar dust present a health hazard to those engaged in lunar exploration? Using rats exposed to lunar dust by nose-only inhalation, we set out to investigate that question

The weaker sex: Male lingcod (Ophiodon elongatus) with blue color polymorphism are more burdened by parasites than are other sex–color combinations

The unusual blue color polymorphism of lingcod (Ophiodon elongatus) is the subject of much speculation but little empirical research; ~20% of lingcod individuals exhibit this striking blue color morph, which is discrete from and found within the same populations as the more common brown morph. In other species, color polymorphisms are intimately linked with host–parasite interactions, which led us to ask whether blue coloration in lingcod might be associated with parasitism, either as cause or effect. To test how color and parasitism are related in this host species, we performed parasitological dissection of 89 lingcod individuals collected across more than 26 degrees of latitude from Alaska, Washington, and California, USA. We found that male lingcod carried 1.89 times more parasites if they were blue than if they were brown, whereas there was no difference in parasite burden between blue and brown female lingcod. Blue individuals of both sexes had lower hepatosomatic index (i.e., relative liver weight) values than did brown individuals, indicating that blueness is associated with poor body condition. The immune systems of male vertebrates are typically less effective than those of females, due to the immunocompromising properties of male sex hormones; this might explain why blueness is associated with elevated parasite burdens in males but not in females. What remains to be determined is whether parasites induce physiological damage that produces blueness or if both blue coloration and parasite burden are driven by some unmeasured variable, such as starvation. Although our study cannot discriminate between these possibilities, our data suggest that the immune system could be involved in the blue color polymorphism–an exciting jumping-off point for future research to definitively identify the cause of lingcod blueness and a hint that immunocompetence and parasitism may play a role in lingcod population dynamics