A QoE based performance study of mobile peer-to-peer live video streaming

Peer-to-peer (P2P) Mobile Ad Hoc Networks (MANETs) are widely envisioned to be a practical platform to mobile live video streaming applications (e.g., mobile IPTV). However, the performance of such a streaming solution is still largely unknown. As such, in this paper, we aim to quantify the streaming performance using a Quality of Experience (QoE) based approach. Our simulation results indicate that video streaming performance is highly sensitive to the video chunk size. Specifically, if the chunk size is small, performance, in terms of both QoE and QoS, is guaranteed but at the expense of a higher overhead. On the other hand, if chunk size is increased, performance can degrade quite rapidly. Thus, it needs some careful fine tuning of chunk size to obtain satisfactory QoE performance. © 2012 IEEE.published_or_final_versio

Study on variation of nutritional value of soy protein isolate after being processed into films

2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Effects of risk assessment and management programme for hypertension on clinical outcomes and cardiovascular disease risks after 12 months: a population-based matched cohort study

Objectives: This study evaluated the effectiveness of a structured multidisciplinary risk assessment and management programme for patients with hypertension (RAMP-HT) who were managed in public primary care clinics but had suboptimal blood pressure (BP) control in improving BP, LDL-cholesterol (LDL-C) and predicted 10-year cardiovascular disease (CVD) risk after 12 months of intervention. Methods: A total of 10 262 hypertension patients with suboptimal BP despite treatment, aged less than 80 years and without existing CVD were enrolled in RAMP-HT between October 2011 and March 2012 from public general out-patient clinics in Hong Kong. Their clinical outcomes and predicted 10-year CVD risk were compared with a matched cohort of hypertension patients who were receiving usual care in general out-patient clinics without any RAMP-HT intervention by propensity score matching. Multivariable linear and logistic regressions were used to determine the independent effectiveness of RAMP-HT after adjusting for potential confounding variables. Results: Compared with the usual care group after 12 months, significantly greater proportions of RAMP-HT participants achieved target BP (i.e. BP 20%) (OR = 1.13, P < 0.01). RAMP-HT participants also had significantly greater reduction in predicted 10-year CVD risk by 0.44% (coefficient = -0.44, P < 0.01). Conclusion: The structured multidisciplinary RAMP-HT was more effective than usual care in achieving target BP, LDL-C and reducing predicted 10-year CVD risk in public primary care patients with suboptimal hypertension control after 12 months of intervention. A long-term follow-up should be conducted to confirm whether the improvement in clinical outcomes can be translated into actual reductions in CVD complications and mortalities and whether such approach is cost-effective.published_or_final_versio

Association between the mood stabilizing treatment of bipolar disorder and risk of suicide attempts: A self-controlled case series study

Bipolar disorder (BPD) is associated with high rates of suicide attempts but the anti-suicidal effect of mood stabilizing agents remains unclear. This study aimed to examine the association between mood stabilizing agents (lithium, valproate, lamotrigine, carbamazepine or antipsychotics) and risk of suicide attempts in patients with BPD using self-controlled case series study design. Among 14,087 patients with BPD who received mood stabilizing agents from 2001 to 2020 in Hong Kong, 1316 patients had at least one suicide attempts during the observation period. An increased risk of suicide attempts was observed 14 days before treatment initiation compared to non-exposed period. Following treatment initiation, an increased risk with smaller magnitude was found with the use of mood stabilizing agents. A lower risk was observed with lithium and antiepileptics while the risk remained attenuated with decreasing magnitude with antipsychotics. During 30-day post-treatment period, the risk was elevated. Therefore, this study suggests that use of mood stabilizing agents is not causally associated with an increased risk of suicide attempts. Indeed, there are potential protective effects of lithium and antiepileptics against suicide attempts. Assiduous monitoring of symptoms relapse and warning signs of suicide should be part of the management plan and discussed between clinicians, caregivers and patients

Birth and early evolution of a planetary nebula

The final expulsion of gas by a star as it forms a planetary nebula --- the ionized shell of gas often observed surrounding a young white dwarf --- is one of the most poorly understood stages of stellar evolution. Such nebulae form extremely rapidly (about 100 years for the ionization) and so the formation process is inherently difficult to observe. Particularly puzzling is how a spherical star can produce a highly asymmetric nebula with collimated outflows. Here we report optical observations of the Stingray Nebula which has become an ionized planetary nebula within the past few decades. We find that the collimated outflows are already evident, and we have identified the nebular structure that focuses the outflows. We have also found a companion star, reinforcing previous suspicions that binary companions play an important role in shaping planetary nebulae and changing the direction of successive outflows.Comment: 9 pages + 3 figures. To appear in Nature, 2 April 199

Age is a predicting factor for the association between CagA positive Helicobacter pylori (Hp) infection and serum pepsinogen I:II ratio in a high gastric cancer risk region in China

published_or_final_versio

Effects of age, education and gender in the Consortium to Establish a Registry for the Alzheimer's Disease (CERAD)-Neuropsychological Assessment Battery for Cantonese-speaking Chinese elders

2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe