The effects of vocal intensity on vocal attack time (VAT)

Includes bibliographical references (p. 23-24)."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."Thesis (B.Sc)--University of Hong Kong, 2010.Vocal attack time (VAT), is a parameter which could provide information about vocal folds attack gesture during pre-phonatory phase. The aim of the present study was to investigate the effects of vocal intensity on VAT. Simultaneously, sound pressure level and electroglottographic signals were collected from 50 participants (25 females and 25 males). The participants were asked to read aloud 12 disyllabic word stimuli using three different intensity levels, comfortable intensity first, then soft intensity and finally loud intensity. The data collected were then subjected to calculation of VAT values using a Matlab-based analysis program. Results indicated that both female and male participants demonstrated the shortest VAT values at loud intensity but the longest VAT values at soft intensity. Both gender groups show similar performance across the three intensity levels. This study provides some empirical data to support the use of VAT as a clinical tool for voice assessment.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Cross-disciplinary collaboration through WuZhiQiao Project to foster cultural exchange and community engagement

In 2013, students of the Technological and Higher Education Institute of Hong Kong (THEi), with the support of WuZhiQiao (WZQ) Charitable Foundation, formed a core team of 11 students to organize and participate in social service projects to help the underprivileged in the Chinese mainland. WuZhiQiao (WZQ) projects, the first cross-region social service engagement by THEi students, bring together students from Hong Kong and the Mainland. WZQ Charitable Foundation aims to help the Chinese traditional village in building Pedestrian Bridge and organizing community projects. Since there are Chinese villages facing flooding during rainy seasons, the local villagers will be trapped inside the village without the chance to go outside or wade outside the village. There are hundreds of such villages and they highly need our help. Each project mainly involves two or three institutes from Hong Kong and the Mainland, and they organize the whole volunteer project including planning, investigation, design, promotion and operation. Through involvement in different states or provinces, WZQ projects provide good chance of communication and interaction between Hong Kong teams and the Mainland teams and advocate intercultural social services. The projects can foster the cultural exchange between Hong Kong and the Mainland. Moreover, the majority of WZQ project members are coming from the fields of engineering, architecture and health care. We can practice our learning from lectures through the project implementation. Different parties are involved in the engineering projects including clients, consultants, contractors, surveyors, engineers and workers. Engineering students can gain good understanding of the holistic picture of a real-life engineering project. We visited the location village for investigation to learn more about the local culture, geometry and the people’s needs and discussed with the Mainland Team through online chatting tools in order to propose the optimal pedestrian building design and other community projects. Having spent over six months in planning and preparation, THEi students will implement a bridge-building and community project in Chongqing in January 2015. Through engagement in this service-learning project, not only the undergraduates of THEi can benefit through personal development but the life quality of the disadvantaged can also be improved

Security and Privacy for Modern Wireless Communication Systems

The aim of this reprint focuses on the latest protocol research, software/hardware development and implementation, and system architecture design in addressing emerging security and privacy issues for modern wireless communication networks. Relevant topics include, but are not limited to, the following: deep-learning-based security and privacy design; covert communications; information-theoretical foundations for advanced security and privacy techniques; lightweight cryptography for power constrained networks; physical layer key generation; prototypes and testbeds for security and privacy solutions; encryption and decryption algorithm for low-latency constrained networks; security protocols for modern wireless communication networks; network intrusion detection; physical layer design with security consideration; anonymity in data transmission; vulnerabilities in security and privacy in modern wireless communication networks; challenges of security and privacy in node–edge–cloud computation; security and privacy design for low-power wide-area IoT networks; security and privacy design for vehicle networks; security and privacy design for underwater communications networks

Animal models of atherosclerosis.

Atherosclerosis is a significant cause of morbidity and mortality globally. Many animal models have been developed to study atherosclerosis, and permit experimental conditions, diet and environmental risk factors to be carefully controlled. Pathophysiological changes can be produced using genetic or pharmacological means to study the harmful consequences of different interventions. Experiments using such models have elucidated its molecular and pathophysiological mechanisms, and provided platforms for pharmacological development. Different models have their own advantages and disadvantages, and can be used to answer different research questions. In the present review article, different species of atherosclerosis models are outlined, with discussions on the practicality of their use for experimentation.GT was supported by a BBSRC Doctoral Training Award and thanks the Croucher Foundation of Hong Kong for the generous support of his clinical assistant professorship. YC is supported by the ESRC

Animal models of atherosclerosis.

Atherosclerosis is a significant cause of morbidity and mortality globally. Many animal models have been developed to study atherosclerosis, and permit experimental conditions, diet and environmental risk factors to be carefully controlled. Pathophysiological changes can be produced using genetic or pharmacological means to study the harmful consequences of different interventions. Experiments using such models have elucidated its molecular and pathophysiological mechanisms, and provided platforms for pharmacological development. Different models have their own advantages and disadvantages, and can be used to answer different research questions. In the present review article, different species of atherosclerosis models are outlined, with discussions on the practicality of their use for experimentation.GT was supported by a BBSRC Doctoral Training Award and thanks the Croucher Foundation of Hong Kong for the generous support of his clinical assistant professorship. YC is supported by the ESRC

Application of explanatory sequential design of mixed methods research in conciliating qualitative and quantitative findings on social stressors and to examine the social problem solving orientation in substance abuse population

Substance abuse has been a problem with every society and across every generation. The increasing number of substance abusers in Hong Kong causes a huge impact to our healthcare system. With the consideration in the complexity of psychosocial nature of this population, the utility of both qualitative and quantitative research methods have been becoming increasingly accepted in health sciences. This is a pioneer project in Hong Kong that employed mixed methods research for substance abuse populations which incorporates evidence of pre-treatment individual characteristics and other specific-tailored treatment factors in promoting changes over time. This study aimed at developing a comprehensive understanding of how individual factors, different social stressors and social problem solving orientation in shaping their behavior. This study covered two phases. The first one was to collect quantitative data in subjects’ ability in problem recognition, treatment readiness, social values and their orientation in social problem solving. A regression model of relapse prediction was constructed, in which, social problem solving was the most prominent factor, followed by treatment readiness, problem recognition and emotional problem. In the second phase of the study, individual semi-structure interview, and qualitative focus group activities of free-listing and pile-sorting were employed to collect qualitative data on the impact of various social stressors like stress from peers, from family, and from work or study. In the final step, we interpreted findings from these two subsets of quantitative and qualitative data. Results indicated stress from peers was the most prominent single stressor of substance abusers, which yielded similar impact as the combination of cross-product of stress from family and from work or study. Moreover, most subjects adopted negative orientation in their social problem solving, in which, stress from work or study noted with the highest response rate in negative orientation in their social problem solving

The impact of the ClearRT™ upgrade on target motion tracking accuracy in Radixact® Synchrony® lung treatments

Background: The objective was to investigate the change in segmentation error of Radixact® Synchrony® lung treatment after its kV imaging system was upgraded from Generation 1 to Generation 2 in the ClearRT™ installation. Materials and methods: Radixact® Lung Synchrony® plans were created for the Model 18023 Xsight® Lung Tracking “XLT” Phantom combined with different lung target inserts with densities of 0.280, 0.500, 0.943 and 1.093 g/cc. After Radixact® Synchrony® treatment delivery using the Generation 1 and Generation 2 kV systems according to each plan, the tracking performance of the two kV systems on each density insert was compared by calculating the root mean square (RMS) error (δRMS) between the Synchrony-predicted motion in the log file and the known phantom motion and by calculating δ95%, the maximum error within a 95% probability threshold. Results: The δRMS and δ95% of Radixact® Synchrony® treatment for Gen1 kV systems deteriorated as the density of the target insert decreased, from 1.673 ± 0.064 mm and 3.049 ± 0.089 mm, respectively, for the 1.093 g/cc insert to 8.355 ± 5.873 mm and 15.297 ± 10.470 mm, respectively, for the 0.280 g/cc insert. In contrast, no such trend was observed in the δRMS or δ95% of Synchrony® treatment using the Gen2 kV system. The δRMS and δ95%, respectively, fluctuated slightly from 1.586 to 1.687 mm and from 2.874 to 2.971 mm when different target inserts were tracked by the Gen2 kV system. Conclusion: With improved image contrast in kV radiographs, the Gen2 kV imaging system can enhance the ability to track targets accurately in Radixact® Lung Synchrony® treatment and reduce the segmentation error. Our study showed that lung targets with density values as low as 0.280 cc/g could be tracked correctly in Synchrony treatment with the Gen2 kV imaging system

The initial shear field in models with primordial local non-Gaussianity and implications for halo and void abundances

We generalize Doroshkevich's celebrated formulae for the eigenvalues of the initial shear field associated with Gaussian statistics to the local non-Gaussian f_{nl} model. This is possible because, to at least second order in f_{nl}, distributions at fixed overdensity are unchanged from the case f_{nl}=0. We use this generalization to estimate the effect of f_{nl}\ne 0 on the abundance of virialized halos. Halo abundances are expected to be related to the probability that a certain quantity in the initial fluctuation field exceeds a threshold value, and we study two choices for this variable: it can either be the sum of the eigenvalues of the initial deformation tensor (the initial overdensity), or its smallest eigenvalue. The approach based on a critical overdensity yields results which are in excellent agreement with numerical measurements. We then use these same methods to develop approximations describing the sensitivity of void abundances on f_{nl}. While a positive f_{nl} produces more extremely massive halos, it makes fewer extremely large voids. Its effect thus is qualitatively different from a simple rescaling of the normalisation of the density fluctuation field \sigma_8. Therefore, void abundances furnish complementary information to cluster abundances, and a joint comparison of both might provide interesting constraints on primordial non-Gaussianity.Comment: 16 pages, 8 figures, match version accepted by MNRA

2D materials for conducting holes from grain boundaries in perovskite solar cells

Grain boundaries in organic-inorganic halide perovskite solar cells (PSCs) have been found to be detrimental to the photovoltaic performance of devices. Here, we develop a unique approach to overcome this problem by modifying the edges of perovskite grain boundaries with flakes of high-mobility two-dimensional (2D) materials via a convenient solution process. A synergistic effect between the 2D flakes and perovskite grain boundaries is observed for the first time, which can significantly enhance the performance of PSCs. We find that the 2D flakes can conduct holes from the grain boundaries to the hole transport layers in PSCs, thereby making hole channels in the grain boundaries of the devices. Hence, 2D flakes with high carrier mobilities and short distances to grain boundaries can induce a more pronounced performance enhancement of the devices. This work presents a cost-effective strategy for improving the performance of PSCs by using high-mobility 2D materials