Automatic systole-diastole classification of mitral valve complex from RT-3D echocardiography based on multiresolution processing

Poster Session: UltrasoundMitral valve repair is one of the most prevalent operations for various mitral valve conditions. Echocardiography, being famous for its low-cost, non-invasiveness and speediness, is the dominant imaging modality used for carrying out mitral valve condition analysis in both pre-operative and intra-operative examinations. In order to perform analysis on different phases of a cardiac cycle, it is necessary to first classify the echocardiograhic data into volumes corresponding to the systole and diastole phases. This often requires tedious manual work. This paper presents a fully-automatic method for systole-diastole classification of real-time three-dimensional transesophageal echocardiography (RT-3D-TEE) data. The proposed method first resamples the data with radial cutting planes, segments the mitral valve by thresholding, and removes noise by median filtering. Classification is then carried out based on the number of identified mitral valve regions. A multiresolution processing scheme is proposed to further improve the classification accuracy by aggregating classification results obtained from different image resolution scales. The proposed method was evaluated against the classification results produced by a cardiologist. Experimental results show that the proposed method, without the use of computationally intensive algorithms or the use of any training database, can achieve a classification accuracy of 91.04%.published_or_final_versio

Fetal Fibronectin Test On Chinese Women With Symptoms Of Preterm Labour: A Pilot Study

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Intrinsic spin torque without spin-orbit coupling

We derive an intrinsic contribution to the nonadiabatic spin torque for nonuniform magnetic textures. It differs from previously considered contributions in several ways and can be the dominant contribution in some models. It does not depend on the change in occupation of the electron states due to the current flow but rather is due to the perturbation of the electronic states when an electric field is applied. Therefore it should be viewed as electric-field-induced rather than current-induced. Unlike previously reported nonadiabatic spin torques, it does not originate from extrinsic relaxation mechanisms or spin-orbit coupling. This intrinsic nonadiabatic spin torque is related by a chiral connection to the intrinsic spin-orbit torque that has been calculated from the Berry phase for Rashba systems.1197Ysciescopu

Perpendicular magnetic anisotropy of two-dimensional Rashba ferromagnets

We compute the magnetocrystalline anisotropy energy within two-dimensional Rashba models. For a ferromagnetic free-electron Rashba model, the magnetic anisotropy is exactly zero regardless of the strength of the Rashba coupling, unless only the lowest band is occupied. For this latter case, the model predicts in-plane anisotropy. For a more realistic Rashba model with finite band width, the magnetic anisotropy evolves from in-plane to perpendicular and back to in-plane as bands are progressively filled. This evolution agrees with first-principles calculations on the interfacial anisotropy, suggesting that the Rashba model captures energetics leading to anisotropy originating from the interface provided that the model takes account of the finite Brillouin zone. The results show that the electron density modulation by doping or an external voltage is more important for voltage-controlled magnetic anisotropy than the modulation of the Rashba parameter.115Ysciescopu

Ambulatory stapled haemorrhoidectomy: A safe and feasible surgical technique

Objective. To compare outcomes following stapled haemorrhoidectomy as an in-patient versus day-surgery procedure. Design. Prospective non-randomised study. Setting. University affiliated hospitals, Hong Kong. Subjects and methods. Forty-eight consecutive patients who underwent stapled haemorrhoidectomy were included in the study. Twenty-four patients had the procedure in an ambulatory setting and the other 24 were treated as in-patients. The symptoms, operative details, postoperative complications, length of hospital stay, pain scores, analgesic requirements, and patient satisfaction scores were collected. Comparison was made between those patients undergoing ambulatory surgery and those treated as in-patients. Results. There were 25 women and 23 men in the study. The mean age was 46.6 years (standard deviation, 12.1 years). The mean operating time was 29.3 minutes (standard deviation, 9.9 minutes). An incomplete 'doughnut' after stapling was found in one patient. There were no other adverse intra-operative events or complications. Postoperative morbidities occurred in eight patients but none required further surgery. One patient in the day-surgery group could not be discharged because of urinary retention and three required re-admission to hospital because of secondary haemorrhage (n=1) or fever (n=2). There were no differences in the postoperative complications, pain scores, analgesic requirements, and patient satisfaction scores between the two groups. The total mean hospital stay was significantly shorter for those undergoing day-surgery stapled haemorrhoidectomy (0.46 versus 1.9 days, P<0.01). The mean follow-up period was 4.6 months (standard deviation, 4.0 months). All patients reported symptomatic improvement during this time and there was no incidence of faecal incontinence. One patient had a soft stricture, one had a fissure, and two had residual skin tags. All of these problems were conservatively managed, without the need for further surgical procedures. Conclusions. Stapled haemorrhoidectomy is a safe and effective operation for haemorrhoids. It is a feasible procedure to perform as day-surgery. The hospital stay can be significantly shortened, thus reducing the costs associated with in-patient care.published_or_final_versio

Resting-state abnormalities in amnestic mild cognitive impairment: a meta-analysis

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Quality of life (QoL) in southern Chinese with systemic lupus erythematosus (SLE)

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Cumulative disease damage in southern Chinese patients with systemic lupus erythematosus (SLE)

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Intelligent agents for matching information providers and consumers on the World-Wide-Web

In this paper, we discuss the various issues in designing intelligent software systems to assist world-wide-web users in locating relevant information. We identify a number of key components in such intelligent systems. These include a web document database management system, a client-based goal-directed search engine, an intelligent learning agent which discovers users' topics of interest by studying their browsing behavior, and an intelligent agent which monitors `hot' web sites. We give examples and suggestions on how these components are designed and implemented. We also describe the architecture of a prototype system that integrates the various components.published_or_final_versio