An exploratory study examining breastfeeding practices among mothers in a maternity hospital in Hong Kong

published_or_final_versio

An exploratory study of the job satisfaction and educational needs of health care workers working in private homes for the elderly in Hong Kong

Health Services Research Fund & Health Care and Promotion Fund: Research Dissemination Reports (Series 2)published_or_final_versio

Learning to read and spell english words by Chinese students

This study examined the structural relationships between (a) the latent independent constructs of orthographic and lexical knowledge and phonological sensitivity and (b) the effect of these constructs on the latent construct of literacy manifested by reading aloud and spelling regular and exception English words in 156 Cantonese-speaking Chinese students (M age = 10.8 years) who were learning English as a second language in Hong Kong. Three carefully designed and item-analyzed indicators subserved the construct of orthographic and lexical knowledge, and another three indicators subserved the construct of phonological sensitivity. Our hypothesis of greater contribution of word-specific orthographic and lexical knowledge than phonological sensitivity to learning to read and spell English words in these Chinese children was supported by results from multiple regression, principal component analyses and especially by structural equation modeling. The various goodness-of-fit indexes showed the appropriateness of the indicators in measuring the latent constructs as well as the relationships among these constructs.published_or_final_versio

The Diurnal Variation on Cardiovascular Endurance Performance of Secondary School Athlete Student

published_or_final_versio

Long Term Restenosis Rate After Carotid Endarterectomy: Comparison of Three Surgical Techniques and Intra-Operative Shunt Use

OBJECTIVE: Closure of the artery during carotid endarterectomy (CEA) can be done with or without a patch, or performed with the eversion technique, while the use of intra-operative shunts is optional. The influence of these techniques on subsequent restenosis is uncertain. Long term carotid restenosis rates and risk of future ipsilateral stroke with these techniques were compared. METHODS: Patients who underwent CEA in the International Carotid Stenting Study were divided into patch angioplasty, primary closure, or eversion endarterectomy. Intra-operative shunt use was reported. Carotid duplex ultrasound was performed at each follow up. Primary outcomes were restenosis of ≥ 50% and ≥ 70%, and ipsilateral stroke after the procedure to the end of follow up. RESULTS: In total, 790 CEA patients had restenosis data at one and five years. Altogether, 511 (64.7%) had patch angioplasty, 232 (29.4%) primary closure, and 47 (5.9%) eversion endarterectomy. The cumulative incidence of ≥ 50% restenosis at one year was 18.9%, 26.1%, and 17.7%, respectively, and at five years it was 25.9%, 37.2%, and 30.0%, respectively. There was no difference in risk between the eversion and patch angioplasty group (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.45 - 1.81; p = .77). Primary closure had a higher risk of restenosis than patch angioplasty (HR 1.45, 95% CI 1.06 - 1.98; p = .019). The cumulative incidence of ≥ 70% restenosis did not differ between primary closure and patch angioplasty (12.1% vs. 7.1%, HR 1.59, 95% CI 0.88 - 2.89; p = .12) or between patch angioplasty and eversion endarterectomy (4.7%, HR 0.45, 95% CI 0.06 - 3.35; p = .44). There was no effect of shunt use on the cumulative incidence of restenosis. Post-procedural ipsilateral stroke was not more common in either of the surgical techniques or shunt use. CONCLUSION: Restenosis was more common after primary closure than conventionally with a patch closure. Shunt use had no effect on restenosis. Patch closure is the treatment of choice to avoid restenosis

Energy- and flux-budget (EFB) turbulence closure model for the stably stratified flows. Part I: Steady-state, homogeneous regimes

We propose a new turbulence closure model based on the budget equations for the key second moments: turbulent kinetic and potential energies: TKE and TPE (comprising the turbulent total energy: TTE = TKE + TPE) and vertical turbulent fluxes of momentum and buoyancy (proportional to potential temperature). Besides the concept of TTE, we take into account the non-gradient correction to the traditional buoyancy flux formulation. The proposed model grants the existence of turbulence at any gradient Richardson number, Ri. Instead of its critical value separating - as usually assumed - the turbulent and the laminar regimes, it reveals a transition interval, 0.1< Ri <1, which separates two regimes of essentially different nature but both turbulent: strong turbulence at Ri<<1; and weak turbulence, capable of transporting momentum but much less efficient in transporting heat, at Ri>1. Predictions from this model are consistent with available data from atmospheric and lab experiments, direct numerical simulation (DNS) and large-eddy simulation (LES).Comment: 40 pages, 6 figures, Boundary-layer Meteorology, resubmitted, revised versio

Detection of Botulinum Neurotoxin Serotype B at Sub Mouse LD50 Levels by a Sandwich Immunoassay and Its Application to Toxin Detection in Milk

Botulinum neurotoxin (BoNT), the causative agent of botulism, a serious neuroparylatic disease, is produced by the anaerobic bacterium Clostridium botulinum and consists of a family of seven serotypes (A-H). We previously reported production of high-affinity monoclonal antibodies to BoNT serotype A.Recombinant peptide fragments of the light chain, the transmembrane and receptor-binding domains of the heavy chain of botulinum neurotoxin type B (BoNT/B) were expressed in Escherichia coli as GST-fusion proteins and purified. These proteins were used to immunize BALB/cJ mice for the generation of monoclonal antibodies (mAbs). Antibody-producing hybridomas were detected using either a direct binding ELISA binding to plate-immobilized BoNT/B, or with a capture-capture ELISA whereby the capacity of the antibody to capture BoNT/B from solution was tested. A total of five mAbs were selected, two of which bound the toxin light chain and three bound the receptor-binding domain of BoNT/B heavy chain. MAb MCS6-27 was identified via capture-capture ELISA and was the only mAb able to bind BoNT/B in solution under physiological conditions. MAbs F24-1, F26-16, F27-33 and F29-40 were identified via direct binding ELISA, and were able to capture BoNT/B in solution only in the presence of 0.5-0.9 mM sodium dodecyl sulphate (SDS). MAb MCS6-27 and an anti-BoNT/B polyclonal antibody were incorporated into a sandwich ELISA that did not require SDS.We report here the generation of monoclonal antibodies to serotype B and the subsequent development of a sensitive sandwich immunoassay. This immunoassay has a detection limit of 100 fg BoNT/B, fifty times more sensitive than the mouse bioassay detection limit of 5 pg BoNT/B. Additionally, this assay detected as little as 39 pg/mL of toxin in skim, 2% and whole milk