Temporal HeartNet: Towards Human-Level Automatic Analysis of Fetal Cardiac Screening Video

We present an automatic method to describe clinically useful information about scanning, and to guide image interpretation in ultrasound (US) videos of the fetal heart. Our method is able to jointly predict the visibility, viewing plane, location and orientation of the fetal heart at the frame level. The contributions of the paper are three-fold: (i) a convolutional neural network architecture is developed for a multi-task prediction, which is computed by sliding a 3x3 window spatially through convolutional maps. (ii) an anchor mechanism and Intersection over Union (IoU) loss are applied for improving localization accuracy. (iii) a recurrent architecture is designed to recursively compute regional convolutional features temporally over sequential frames, allowing each prediction to be conditioned on the whole video. This results in a spatial-temporal model that precisely describes detailed heart parameters in challenging US videos. We report results on a real-world clinical dataset, where our method achieves performance on par with expert annotations.Comment: To appear in MICCAI, 201

Regulation of cell proliferation by ion channels in human mesenchymal stem cells

Oral presentationpublished_or_final_versionThe 15th Annual Research Conference of the Department of Medicine, The University of Hong Kong, Hong Kong, 16 January 2010. In Hong Kong Medical Journal, 2010, v. 16, suppl. 1, p. 65, abstract no. 11

Human cardiac Kv4.3 channels are regulated by protein tyrosine kinases

Poster presentationpublished_or_final_versionThe 15th Annual Research Conference of the Department of Medicine, The University of Hong Kong, Hong Kong, 16 January 2010. In Hong Kong Medical Journal, 2010, v. 16, suppl. 1, p. 64, abstract no. 11

Modelling the Effects of Nifedipine on Ventricular and Myometrial Cells of Pregnant Rats

In this study we have used computational models to investigate the effects of nifedipine on two different cell types; the rat ventricular cell and the rat myometrial cell. Nifedipine is a calcium-channel blocker commonly used by health services around the world to treat both cardiovascular conditions (such as high blood pressure) and as a tocolytic to treat pre-term birth. The latter usage is prohibited in pregnant patients with pre-existing heart conditions. By applying discrete blocks to the L-Type calcium channels in each cell model we were able to simulate the presence of nifedipine at varying concentrations. Using the electrical and ionic responses to blocking these channels as indicators, we have been able to quantify and describe the effects of nifedipine in each cell type and compare them qualitatively. Although any level of block will reduce the maximum level of intracellular calcium in the myometrial cell, a 60% block or higher is required to produce a change in the morphology of the calcium transient. It remains to be shown if the dose required to achieve this could result in a patient with a pre-existing heart condition experiencing hypotension or other pathological cardiac conditions during labor, if nifedipine is used as a tocolytic

Holonomic quantum computation using rf superconducting quantum interference devices coupled through a microwave cavity

We propose a different scheme to realize holonomic quantum computation with rf superconducting quantum interference device (SQUID) qubits in a microwave cavity. In this scheme associated with the non-Abelian holonomies, the single-qubit gates and a two-qubit controlled-PHASE gate as well as a controlled-NOT gate can be easily constructed by tuning adiabatically the Rabi frequencies of classical microwave pulses coupled to the SQUIDs. The fidelity of these gates is estimated to be possibly higher than 90% with the current technology. © 2005 The American Physical Society.published_or_final_versio

BKca and hEAG channels modulate proliferation and differentiation of human marrow-derived mesenchymal stem cells

INTRODUCTION: Bone marrow–derived mesenchymal stem cells (MSCs) are a promising cell source for regenerative medicine. However, cellular physiology is not fully understood in human MSCs. The present study was to determine the potential role of the dominant functional ion channels, large-conductance Ca2+-activated potassium (BKCa) channel, ether-a-go-go potassium (hEAG1) channel in regulating cell functions, including ...published_or_final_versionThe 17th Medicial Research Conference, Department of Medicine, The University of Hong Kong, 14 January 2012. In Hong Kong Medical Journal, 2012, v. 18 n. 1, suppl. 1, p. 63, abstract no. 10

Demand Side Load Management for Big Industrial Energy Users under Blockchain-Based Peer-to-Peer Electricity Market

© 2010-2012 IEEE. Blockchain is the key technology of Bitcoin and other cryptocurrencies, and it is one of the most exciting technologies changing the world as of late. Targeting at big industrial energy users, this paper first presents a new market structure (i.e., transaction rules) under existing blockchain-based electricity transaction platforms to cover popular types of markets such as contract, day-ahead, adjustment and balancing markets; and then focuses on the optimal load management problem for a particular industrial user. The proof-of-work cost from blockchain is also modeled. A key feature of this load management problem is that the user has direct control on its own load. The obtained load control model is much more accurate than existing approaches in which system operators or demand aggregators cannot control load directly and have to rely on inaccurate estimations. As a case study, the pumping load of a water supply plant is investigated to illustrate how the demand load is managed under this blockchain-based market. From the case study, it is found that 18.9% of total cost can be saved under this new market structure

Holographic non-relativistic fermionic fixed point and bulk dipole coupling

Inspired by the recently discovered non-relativistic fermionic fixed points, we investigate how the presence of bulk dipole coupling modifies the spectral function at one of these novel fixed points. As a result, although the infinite flat band is always visible in the presence of the bulk dipole coupling as well as chemical potential, the band is modified in a remarkable way at small momenta up to the order of magnitude of bulk dipole coupling. On the other hand, like a phoenix, a new Fermi surface sprouts from the formed gap when the bulk dipole coupling is pushed up further such as to overshadow the charge parameter, which is obviously different from what is found at the relativistic fixed points.Comment: JHEP style, 1+17 pages, 9 figures, 1 table, typos corrected, references added, version to appear in JHE

Enhanced flight performance by genetic manipulation of wing shape in Drosophila

Insect wing shapes are remarkably diverse and the combination of shape and kinematics determines both aerial capabilities and power requirements. However, the contribution of any specific morphological feature to performance is not known. Using targeted RNA interference to modify wing shape far beyond the natural variation found within the population of a single species, we show a direct effect on flight performance that can be explained by physical modelling of the novel wing geometry. Our data show that altering the expression of a single gene can significantly enhance aerial agility and that the Drosophila wing shape is not, therefore, optimized for certain flight performance characteristics that are known to be important. Our technique points in a new direction for experiments on the evolution of performance specialities in animals

Identification of transient receptor potential channels in human atrial myocytes

In Hong Kong Medical Journal, 2011, v. 17, suppl. 1, p. 68, abstract no. 115published_or_final_versionThe 16th Medical Resarch Conference (MRC), The University of Hong Kong, Hong Kong, China, 22 January 2011. In Hong Kong Medical Journal, 2011, v. 17, suppl. 1, p. 68, abstract no. 11