Field Evaluation of Four Low-cost PM Sensors and Design, Development and Field Evaluation of A Wearable PM Exposure Monitoring System

To mitigate the significant biases/errors in research studying the associations between PM and health, which are introduced by the coarse/inadequate assessments of PM exposure from conventional PM monitoring paradigm, a personalized monitoring system consisting of a low-cost wearable PM device is proposed. However, due to the absence of a unifying evaluation protocol for low-cost PM sensors, the evaluation results/performance specifications from existing studies/datasheets are of limited reference values when attempting to determine the best candidate for the proposed system. In this regard, the authors appeal to the research community to develop a standardized evaluation protocol for low-cost PM sensors/devices, and a unifying attempt is established in this manuscript by adopting the definitive terminology from international documents and the evaluation metrics regarded as best practices. Collocated on the rooftop of the HKUST Supersite, four empirically selected PM sensors were compared against each other and calibrated against two reference monitors. They were then evaluated against the reference following the protocol. The PlanTower PMS-A003 sensor was selected for the wearable device as it outperformed the others in terms of affordability, portability, detection capability, data quality, as well as humidity and condensation insusceptibility. An automated approach was proposed to identify and remove the condensation associated abnormal measurements. The proposed device has better affordability and portability as well as similar usability and data accessibility compared to those existing devices recognized. The first 10 devices were also evaluated and calibrated at the Supersite. Additional 120 units were manufactured and delivered to the subjects to acquire their daily PM2.5 exposures for investigating the association with subclinical atherosclerosis

Towards Personalized Healthcare in Cardiac Population: The Development of a Wearable ECG Monitoring System, an ECG Lossy Compression Schema, and a ResNet-Based AF Detector

Cardiovascular diseases (CVDs) are the number one cause of death worldwide. While there is growing evidence that the atrial fibrillation (AF) has strong associations with various CVDs, this heart arrhythmia is usually diagnosed using electrocardiography (ECG) which is a risk-free, non-intrusive, and cost-efficient tool. Continuously and remotely monitoring the subjects' ECG information unlocks the potentials of prompt pre-diagnosis and timely pre-treatment of AF before the development of any life-threatening conditions/diseases. Ultimately, the CVDs associated mortality could be reduced. In this manuscript, the design and implementation of a personalized healthcare system embodying a wearable ECG device, a mobile application, and a back-end server are presented. This system continuously monitors the users' ECG information to provide personalized health warnings/feedbacks. The users are able to communicate with their paired health advisors through this system for remote diagnoses, interventions, etc. The implemented wearable ECG devices have been evaluated and showed excellent intra-consistency (CVRMS=5.5%), acceptable inter-consistency (CVRMS=12.1%), and negligible RR-interval errors (ARE<1.4%). To boost the battery life of the wearable devices, a lossy compression schema utilizing the quasi-periodic feature of ECG signals to achieve compression was proposed. Compared to the recognized schemata, it outperformed the others in terms of compression efficiency and distortion, and achieved at least 2x of CR at a certain PRD or RMSE for ECG signals from the MIT-BIH database. To enable automated AF diagnosis/screening in the proposed system, a ResNet-based AF detector was developed. For the ECG records from the 2017 PhysioNet CinC challenge, this AF detector obtained an average testing F1=85.10% and a best testing F1=87.31%, outperforming the state-of-the-art

Ten Years’ Research on a Cardiovascular Tonic: A Comprehensive Approach—From Quality Control and Mechanisms of Action to Clinical Trial

Objective. Mortality arising from cardiovascular pathologies remains one of the highest. Maintenance of cardiovascular health therefore remains a universal concern. Interventional therapies and medications have made impressive advances, but preventive measures would be of the same importance. Method. Ten years’ search for a simple herbal formula has resulted in a two-herb combination, consisting of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix. The formula has been studied extensively on cardiovascular biological platforms and then put on three clinical trials. Results. In the laboratory, the formula was found to have the biological effects of anti-inflammation, anti-oxidation, anti-foam cell formation on vascular endothelium, and vasodilation. Clinical trials using ultrasonic carotid intima thickness as a surrogate marker showed very significant benefits. No significant adverse effects were encountered. Conclusion. It is therefore recommended that the herbal formula could be used as an adjuvant therapy in cardiac patients under treatment or as a preventive agent among the susceptible

Acute myocardial infarction in the Chinese in Hong Kong

published_or_final_versionMedicineMasterDoctor of Medicin

Effects of Drain Bias on Memory-Compensated Analog Predistortion Power Amplifier for WCDMA Repeater Applications

2

Genetics of Parkinson’s Disease - A Clinical Perspective

Discovering genes following Medelian inheritance, such as autosomal dominant-synuclein and leucine-rich repeat kinase 2 gene, or autosomal recessive Parkin, P-TEN-induced putative kinase 1 gene and Daisuke-Junko 1 gene, has provided great insights into the pathogenesis of Parkinson’s disease (PD). Genes found to be associated with PD through investigating genetic polymorphisms or via the whole genome association studies suggest that such genes could also contribute to an increased risk of PD in the general population. Some environmental factors have been found to be associated with genetic factors in at-risk patients, further implicating the role of gene-environment interactions in sporadic PD. There may be confusion for clinicians facing rapid progresses of genetic understanding in PD. After a brief review of PD genetics, we will discuss the insight of new genetic discoveries to clinicians, the implications of ethnic differences in PD genetics and the role of genetic testing for general clinicians managing PD patients

Methylenetetrahydrofolate reductase gene A222V polymorphism and risk of ischemic stroke

The 5,10-methylenetetrahydrofolate reductase (MTHFR) gene 677C→T polymorphism causes an A222V amino acid change which affects MTHFR enzyme activity and can increase homocysteine, a vascular disease risk factor. This polymorphism was examined for association with stroke. In a case-control study of 241 ischemic stroke patients and 304 controls in Hong Kong, the V allele increased in stroke [28% vs. 20%, odds ratio (OR) 1.5, p=0.003]. A lack of significance for the increase in the VV genotype (7.5% vs. 4.6%, OR 1.7, p=0.16) may be due to its rarity in this region. V-allele carriers had more severe strokes (according to the NIH stroke scale). The association of the V allele with stroke occurred mostly in women or older subjects and was due to decreasing V allele frequency with age, as seen in other studies. This V frequency decline with age might be due to a loss of V-carrying controls from a higher risk of cancer, vascular disease, bone fracture, and kidney failure when folate is sparse. Examination of previous studies revealed that the association of VV genotype with stroke appeared stronger in Japan than elsewhere, possibly due to dietary differences. Perhaps folate supplementation for stroke prevention would particularly benefit VV individuals in such high-risk regions

Carotid artery intima media thickness, plaque and framingham cardiovascular score in Asia, Africa/Middle East and Latin America: the PARC-AALA Study

Objective The PARC-AALA (Paroi arterielle et Risque Cardiovasculaire in Asia Africa/ Middle East and Latin America) study was designed to evaluate the correlation between intima-media thickness of the common carotid artery (CCAIMT), carotid plaque and absolute cardiovascular risk in a multi-ethnic population

The Different Impact of PM2.5 on Atherogenesis in Overseas vs. Native Chinese in the CATHAY Study

Air pollution (PM2.5) has been associated with cardiovascular disease (CVD) globally and with early atherosclerosis surrogate markers in modernized China. A sizeable number of Chinese have migrated overseas, with an increase in their vulnerability to CVD. To evaluate the impact of PM2.5 air pollution on atherogenesis in native vs. overseas Chinese, we recruited 756 asymptomatic native Chinese and 507 age- and gender-matched overseas Chinese from Sydney and San Francisco. Their cardiovascular profiles were evaluated. PM2.5 was derived from remote sensing technology; atherosclerosis surrogate markers, flow-mediated dilation (FMD) and carotid intima-media thickness (IMT) were measured by ultrasound. The native Chinese had a higher proportion of smokers as well as higher blood pressure, glucose, metabolic syndrome and PM2.5 exposure (p &lt; 0.001), but lower lipids and folate than the overseas Chinese (p &lt; 0.0001). Carotid IMT was lower in the native Chinese (p &lt; 0.0001), but the other vascular parameters were similar. A multivariate regression revealed that FMD in the native Chinese was related to the male gender, age and location; in the overseas Chinese, it was related to age, but not to PM2.5. Carotid IMT in the native Chinese was related to PM2.5, independent of atherosclerotic risk factors and location (R2 = 0.384, F = 34.5, p &lt; 0.0001) whereas in the overseas Chinese, IMT was related to the male gender and age, but not to PM2.5 or overseas location (R2 = 0.282, F = 19.7, p &lt; 0.0001). PM2.5 had a greater impact on atherogenesis in the native Chinese, independent of traditional risk factors, with implications for preventive strategies