TCP-Swift: An end-host enhancement scheme for TCP over satellite IP networks

A new transport layer protocol called TCP-Swift is proposed for enhancing the TCP performance over satellite IP networks. TCP-Swift replaces the conventional TCP slow start and fast recovery algorithms by speedy start and speedy recovery. With speedy start, a TCP-Swift sender opens up its congestion window in only two round trip times. This significantly shortens the time needed in probing the network for equilibrium state. With speedy recovery, we can infer the cause of a packet loss by observing the ACK stream received at the sender. If the loss is due to wireless transmission error, the sender's congestion window can be re-opened up more aggressively to fully utilize the available satellite link bandwidth. We show that TCP-Swift outperforms existing TCP schemes by simulations.published_or_final_versio

G-Snoop: Enhancing TCP performance over wireless networks

Focusing on a general wireless network where a wireless link can be at any link along the sender-to-receiver path, a new TCP enhancement scheme, called Generalized-Snoop (G-Snoop), is proposed. Since many existing applications are built on top of TCP, it is essential that any TCP enhancement scheme should be transparent to the end-systems as well as the fixed networks. To achieve this, G-Snoop only needs to be implemented at the wireless gateways, no other parts of the network require modifications. With G-Snoop, TCP senders are shielded from non-congestion packet loss and thus no unnecessary congestion control mechanisms will be performed. Simulation results show that significant throughout gain can be obtained with G-Snoop.published_or_final_versio

Neuroeconomics of health care financing options: willingness to pay and save

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Performance of a prehospital trauma diversion system in Hong Kong, China

postprin

Out-of-hospital cardiac arrest in Hong Kong: a territory-wide study

INTRODUCTION: Out-of-hospital cardiac arrest is a global health care problem. Like other cities in the world, Hong Kong faces the impact of such events. This study is the first territory-wide investigation of the epidemiology and outcomes of out-of-hospital cardiac arrest in Hong Kong. It is hoped that the findings can improve survival of patients with cardiac arrest. METHODS: This study was a retrospective analysis of the prospectively collected data on out-of-hospital cardiac arrest managed by the emergency medical service from 1 August 2012 to 31 July 2013. The characteristics of patients and cardiac arrests, timeliness of emergency medical service attendance, and survival rates were reported with descriptive statistics. Predictors of 30-day survival were evaluated with logistic regression. RESULTS: A total of 5154 cases of out-of-hospital cardiac arrest were analysed. The median age of patients was 80 years. Most arrests occurred at the patient's home. Ventricular fibrillation or ventricular tachycardia was identified in 8.7% of patients. The median time taken for the emergency services to reach the patient was 9 minutes. The median time to first defibrillation was 12 minutes. Of note, 2.3% of patients were alive at 30 days or survived to hospital discharge; 1.5% had a good neurological outcome. Location of arrest, initial electrocardiogram rhythm, and time to first defibrillation were independent predictors of survival at 30 days. CONCLUSION: The survival rate of out-of-hospital cardiac arrest patients in Hong Kong is low. Territory-wide public access defibrillation programme and cardiopulmonary resuscitation training may help improve survival.published_or_final_versio

Survival of molar teeth after resective periodontal therapy - A retrospective study

AIM: To study outcomes of molar teeth after resective therapy performed with the intention to prolong the lifespan of teeth having one or more unsaveable roots, and without which tooth extraction would be inevitable. MATERIAL AND METHODS: Clinical records of 149 subjects who had undergone resective therapy were retrieved. Demography and dental history were recorded, and a recall examination was undertaken. Cox regression models were performed. RESULTS: Of the 149 resective therapies, 132 (88.6%) were performed for periodontal reasons. Eighty-nine (59.7%) teeth subjected to resective therapies had been extracted by the time of recall (mean 10 years post-resection). The median survival period was 74 months. Factors significantly associated with shorter survival duration of teeth subjected to resective therapy were: age at resective therapy; pre-operative radiographic bone height of the remaining root(s) <50%; pre-treatment mobility II or above and not being splinted to neighbouring teeth nor incorporated as a bridge abutment. CONCLUSION: There was increased risk of tooth loss with increasing age at resection, grade II mobility or above, and reduced pre-operative radiographic bone heights around roots to remain. Splinting of a resected tooth to neighbouring teeth appeared to confer a protective effect towards its survival.postprin

Type-2 diabetes mellitus, metabolic control, serum inflammatory factors, lifestyle, and periodontal status

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Management of obesity in the National Health and Nutrition Examination Survey (NHANES), 2007-2008

PURPOSE: The prevalence of obesity has been increasing in the United States. We set out to investigate the use of pharmacologic and non-pharmacologic therapy for the treatment of obesity in recent years. METHODS: We included 2630 men and 2702 women who took part in the National Health and Nutrition Examination Survey from 2007 to 2008. We analyzed their demographic and anthropometric data and their weight and drug history. RESULTS: A total of 45.9% of men and 45.0% of women were candidates for treatment (body mass index >/=30 kg/m(2), or >/=27 kg/m(2) with risk factors). Among these participants, 85.1% considered themselves overweight, 90.1% would like to lose weight, 61.9% had dietary changes, 36.5% exercised, 3.7% took nonprescription drugs, and 2.2% took prescription drugs to control weight during the preceding year. During the preceding month, 0.5% and 0.1% of participants were taking phentermine and orlistat, respectively. There were no participants on sibutramine. CONCLUSIONS: Although obesity is highly prevalent, only a small percentage of obese Americans are on anti-obesity medication. The withdrawal of sibutramine would have minimal impact on the general population. There is a need for more lifestyle changes in the majority of obese individuals.published_or_final_versio

Pharmacological management of obesity in the National Health and Nutrition Examination Survey (NHANES) 2007-8

Poster Session II: Translational & Clinical: Clinical Pharmacologypublished_or_final_versionThe 16th Medical Research Conference, Department of Medicine, The University of Hong Kong, Hong Kong, 22 January 2011. In Hong Kong Medical Journal, 2011, v. 17 n. 1, Suppl. 1, p. 50, abstract no. 8

Surgical treatment of penile curvature

OBJECTIVE: To review long-term efficacy and complications of surgical treatment of penile curvature in a Chinese population. DESIGN: Retrospective review. SETTING: Regional hospital, Hong Kong. PATIENTS. Patients who underwent surgical treatment of penile curvature between January 1997 and March 2005 inclusive. INTERVENTION: Penile curvature corrective surgery. MAIN OUTCOME MEASURES: Penile curvature recurrence, early and late complications. RESULTS: Of 22 patients who underwent surgical treatment of penile curvatures, 19 had congenital and three had acquired diseases. The mean angle of deformity was 52.5 (range, 20-90) degrees. Ten patients had Nesbit procedures, ten had modified Nesbit procedures, and two underwent vein grafting. Twenty patients had residual or recurrent penile curvatures at a mean follow-up of 50.9 months. Fifteen patients had less than 30 degrees curvature and five had 30 to 60 degrees curvature. Early complications included wound infection (n=3), penile skin necrosis (n=1) treated by skin graft, and urethral injury (n=1). Three patients had erectile dysfunction; four complained of glans paraesthesia. Penile shortening (mean, 1.4 cm) and palpable knots were common late complications. A total of 19 patients were satisfied with the final outcomes. CONCLUSIONS: Surgical treatment of penile curvature produces long-term patient satisfaction. Preoperative counselling on potential recurrence and common minor complications is crucial to produce favourable outcomes.published_or_final_versio