Tax-driven Bunching of Housing Market Transactions: The case of Hong Kong

We study the implications of property market transaction tax. As property buyers are obligated to pay a transaction tax (“stamp duty”, or SD) where the rate increases with the value of the transaction, there are incentives to trade at or just below the cutoff points of the tax schedule. Thus, both “bunching in transactions” and “underpricing” should be observed near those cutoffs. Furthermore, the bunching points should change with the tax schedule. We confirm these conjectures with a rich dataset from the Hong Kong housing market and provide a measure of the tax avoidance

The Impact of Cardiac Comorbidity Sequence at Baseline and Mortality Risk in Type 2 Diabetes Mellitus: A Retrospective Population-Based Cohort Study.

The presence of multiple comorbidities increases the risk of all-cause mortality, but the effects of the comorbidity sequence before the baseline date on mortality remain unexplored. This study investigated the relationship between coronary heart disease (CHD), atrial fibrillation (AF) and heart failure (HF) through their sequence of development and the effect on all-cause mortality risk in type 2 diabetes mellitus. This study included patients with type 2 diabetes mellitus prescribed antidiabetic/cardiovascular medications in public hospitals of Hong Kong between 1 January 2009 and 31 December 2009, with follow-up until death or 31 December 2019. The Cox regression was used to identify comorbidity sequences predicting all-cause mortality in patients with different medication subgroups. A total of 249,291 patients (age: 66.0 ± 12.4 years, 47.4% male) were included. At baseline, 7564, 10,900 and 25,589 patients had AF, HF and CHD, respectively. Over follow-up (3524 ± 1218 days), 85,870 patients died (mortality rate: 35.7 per 1000 person-years). Sulphonylurea users with CHD developing later and insulin users with CHD developing earlier in the disease course had lower mortality risks. Amongst insulin users with two of the three comorbidities, those with CHD with preceding AF (hazard ratio (HR): 3.06, 95% CI: [2.60-3.61], < 0.001) or HF (HR: 3.84 [3.47-4.24], < 0.001) had a higher mortality. In users of lipid-lowering agents with all three comorbidities, those with preceding AF had a higher risk of mortality (AF-CHD-HF: HR: 3.22, [2.24-4.61], < 0.001; AF-HF-CHD: HR: 3.71, [2.66-5.16], < 0.001). The sequence of comorbidity development affects the risk of all-cause mortality to varying degrees in diabetic patients on different antidiabetic/cardiovascular medications

Historical perspective and recent progress in cardiac ion channelopathies research and clinical practice in Hong Kong

Cardiac ion channelopathies encompass a set of inherited or acquired conditions that are due to dysfunction in ion channels or their associated proteins, typically in the presence of structurally normal hearts. They are associated with the development of ventricular arrhythmias and sudden cardiac death. The aim of this review is to provide a historical perspective and recent advances in the research of the cardiac ion channelopathies, Brugada syndrome, long QT syndrome and catecholaminergic polymorphic ventricular tachycardia, in Hong Kong, China. In particular, recent works on the development of novel predictive models incorporating machine learning techniques to improve risk stratification are outlined. The availability of linked records of affected patients with good longitudinal data in the public sector, together with multidisciplinary collaborations, implies that ion channelopathy research efforts have advanced significantly

Development of biomimetic materials : synthesis, helical structures, self-assembling morphologies, and biological activities of amphiphilic polyacetylenes containing biocompatible building blocks

Polymerization of a series of novel acetylenic monomers bearing different hydrophilic entities such as ethylene glycols (1), amino acids (2), saccharides (3), and nucleosides (4) has been studied. The monomers can be successfully polymerized by Rh-based complexes, but not by metathesis catalysts such as WCl6 and MoCl5. 1H NMR spectroscopy revealed strong signals characteristic of cis olefinic protons of the polymers, indicative of their high stereoregularities. Such signals, however, became unclear (broader) for the amino acid-containing polyacetylenes when less polar solvents like chloroform, dichloromethane, were used, demonstrating that their polymer chains were folded and their molecular motions were hence restricted by internal hydrogen bonding. Polyacetylene is a symmetric chain of conjugated macromolecule, whose chain symmetry can, however, be broken by external and internal perturbations, generating spirally rotating molecular wires. The external approach involves the use of asymmetric force field and interactive complexing agents, while the internal one involves the covalent attachment of stereogenic pendants to the conjugated backbone at the molecular level. Incorporation of above naturally occurring building blocks (2-4) into the polyacetylene structure therefore results in the formation of not only amphiphilic but also optically active polymers, whose chain helicity can be continuously and reversibly tuned by simple external stimuli such as solvent, pH, temperature, and additive. Such tuned behaviors have been fully imaged in their corresponding circular dichroism activities and optical rotations, illustrating that stabilization of their single-handed helical conformations relies on intra- and inter-chain hydrogen bonds and is affected by bulkiness of the pendant groups of the macromolecular chains. The amphiphilic polyacetylenes, in response to the changes in their environments, self-associate into robust organizational morphologies reminiscent of natural hierarchical structures such as helix, sphere, twisted cable, twisted ribbon, vesicle, tubule, twisted tubule, hairpin loop, extended fibril, coiling ribbon, honeycomb pattern, and mollusk shape. Some of the structures have been rarely reported in scientific literature. AFM and TEM observations revealed co-existence of the vesicular and nanotubular structures, strongly supporting that formation of the tubules resembles the biological architectural process, as resulted from coalescence of the vesicles. Further variation of the tubular structure promoted the formation of multi-stranded helical tubes by winding up the single-stranded nanotubules. The ethylene glycol-containing amphiphiles are capable of forming micellar structures, driving crystal growth of carbazole molecules to form unique intriguing morphologies depending on the structure of the pendant groups. Biological studies revealed that the amino acid-containing polyacetylenes are generally biocompatible with HeLa cells without serious cytotoxicity effects up to a dosage of 22.24 μg/cm2. Growth of the HeLa cells can be stimulated by the addition of a small amount of a monosaccharide-containing polyacetylene

Multilingual home environment and specific language impairment: a case-control study in Chinese children

published_or_final_versionMedical SciencesMasterMaster of Medical Science

How can Sweden’s “trash economy” be explained by international relations theories?

published_or_final_versionInternational and Public AffairsMasterMaster of International and Public Affair