A preliminary investigation of prenatal stress and risk of autism spectrum disorder

Thesis (B.Sc)--University of Hong Kong, 2010.Includes bibliographical references (p. 26-28)."A dissertation submitted in partial fulfillment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2010."This paper was a retrospective survey investigating the association between prenatal stress and risk of ASD in Chinese population. Twenty-eight mothers of children diagnosed with ASD, and thirty-eight mothers of children with no diagnoses of neurodevelopmental diseases were interviewed. The survey mainly investigated the incidence and intensity of prenatal stress, birth conditions and developmental problems of children, maternal health conditions, and the participants’ coping strategies towards prenatal stress. Higher overall intensity and higher incidence of prenatal stress were found to be experienced by mothers of ASD children. The ASD group also showed higher incidence of prematurity, birth complications, health problems, maternal illnesses, advanced maternal age, and developmental problems. This proposed prenatal stress as a possible risk factor of ASD and the other developmental problems associated with ASD.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

The economic link-up of Hong Kong and Guangdong : structural and development problems

The phenomenal link-up between the Hong Kong and Guangdong economies has been proceeding at a remarkable speed since the launching of the Chinese economic reform in late 1978. The process has largely been market-driven and seems to suit the short-run comparative advantage on both sides. In essence, however, it has been a result of a reallocation of resources across the border, made possible by China\u27s open policy. It has not yet led to a benign form of developmental upgrading which embodies the strengthening of the long-term foundation for productivity and competitiveness enhancement. Indeed, the tremendous windfall profits obtained so far could be regarded as a disincentive for R & D investments as well as beneficial decisions that may incur painful side effects in the short run. Problems which are structural and developmental in nature, including bias and duplication in production patterns, inflationary pressure, widening income inequality, and the loss of competitiveness, have emerged in both Hong Kong and Guangdong. These problems could be traced to the lack of countervailing forces that promote far-sighted strategies, vis-a-vis short-termism driven by market supplies and demands and yearly profit maximization. In this paper, we argue that while better coordination should be pursued to ensure mutually beneficial developments and to avoid duplication in efforts and undesirable convergence in industrial structures, the future trajectories of the two economies will not and cannot be identical. Hong Kong and Guangdong are different in size and endowments, and face dissimilar political and economic frameworks. Independent policies and measures to nurture specific advantages and to solve internal problems have to be made. Indeed, a certain distancing in economic relations between the two economies will be healthy

Single-channel electroencephalographic recording in children with developmental coordination disorder: Validity and influence of eye blink artifacts

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Evaluation of deformed image-based dose calculations for adaptive radiotherapy of nasopharyngeal carcinoma

The ultimate goal of adaptive radiotherapy (ART) is to deliver truly customized radiation treatments. Currently, the quality of cone-beam computed tomography (CBCT) images is still inferior to that of conventional CT images in contour delineations and dose calculations for replanning purposes. This retrospective study aims to evaluate the dosimetric accuracy of using deformed conventional CT images for dose calculations, in the hope of inferring the feasibility of ART using planning CT (PCT) images that deformed to up-to-date CBCT images for patients with nasopharyngeal carcinoma (NPC). Thirty consecutive patients with NPC who had undergone 1 replan in their radiotherapy treatments were selected. The pretreatment PCT images were deformed to match the mid-treatment PCT images by deformable image registration. The same volumetric modulated arc therapy plan was then calculated on the deformed PCT images. The resulting dose distributions and dose volume histograms of the tumors and organs at risk (OARs) were compared with the original plan. Five dose levels, D98%, D95%, D50%, D5%, and D2%, were recorded for 9 NPC targets. Four dose levels, Dmax, D10%, D50%, and Dmean, were recorded for 15 OARs. The greatest percentage difference in observed dose for D98%, D95%, D50%, D5%, and D2% of the targets were 1.71%, 1.55%, 0.64%, 0.97%, and 1.13%, respectively. The greatest percentage difference in observed dose for Dmax, D10%, D50%, and Dmean of the OARs were -26.51% (left optic nerve), -17.06% (left optic nerve), 56.70% (spinal cord), and 18.97% (spinal cord), respectively. In addition, 29 of 45 (64%) dosimetric end points of the targets showed statistically significant dose differences (p < 0.05) between the original plan and the plan calculated on deformed images. Forty-nine of 60 (82%) dosimetric end points of the OARs also showed statistically significant dose differences (p < 0.05). Dose calculations using deformed PCT images could result in significant dose uncertainties in target volumes and OARs. Larger dose deviations were found in OARs in comparison with target volumes. The spinal cord and optic nerve showed the greatest percentage dose differences and the clinical significance has yet to be determined. Deformable registration error was believed to be the problem causing the dose deviations. Owing to unknown clinical significanceof dose deviation results obtained from this study, a conventional CT scan is still required for replanning in patients with NPC who are experiencing significant anatomical changes during the course of radiation treatment. [Abstract copyright: Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

The pseudo scalar form factor of the nucleon, the sigma-like term, and the L0+L_0^+ amplitude for charged pion electro-production near threshold

The pseudo scalar form factor, which represents the pseudo scalar quark density distribution due to finite quark masses on the nucleon, is shown to manifest itself with the induced pseudo scalar form factor in the $L_0^+$ amplitude for the charged pion electro-production. Both form factors show their own peculiar momentum dependence. Under the approximation on which the Goldberg-Treimann relation holds, a sum of both form factors' contributions accounts for the t-channel contribution in the charged pion electro-production near threshold.Comment: 10 page