Publications by authors named "Kwok K"

Background: Non-hospital residential facilities are important reservoirs for MRSA transmission. However, conclusions and public health implications drawn from the many mathematical models depicting nosocomial MRSA transmission may not be applicable to these settings. Therefore, we reviewed the MRSA transmission dynamics studies in defined non-hospital residential facilities to: (1) provide an overview of basic epidemiology which has been addressed; (2) identify future research direction; and (3) improve future model implementation.

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Purpose: In cardiac electrophysiology, a long and flexible catheter is delivered to a cardiac chamber for the treatment of arrhythmias. Although several robot-assisted platforms have been commercialized, the disorientation in tele-operation is still not well solved. We propose a validation platform for robot-assisted cardiac EP catheterization, integrating a customized MR Safe robot, a standard clinically used EP catheter, and a human-robot interface.

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The azimuthal anisotropy Fourier coefficients (v_{n}) in 8.16 TeV p+Pb data are extracted via long-range two-particle correlations as a function of the event multiplicity and compared to corresponding results in pp and PbPb collisions. Using a four-particle cumulant technique, v_{n} correlations are measured for the first time in pp and p+Pb collisions.

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The first observation of electroweak production of same-sign W boson pairs in proton-proton collisions is reported. The data sample corresponds to an integrated luminosity of 35.9    fb^{-1} collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC.

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An inclusive search for the standard model Higgs boson (H) produced with large transverse momentum (p_{T}) and decaying to a bottom quark-antiquark pair (bb[over ¯]) is performed using a data set of pp collisions at sqrt[s]=13  TeV collected with the CMS experiment at the LHC. The data sample corresponds to an integrated luminosity of 35.9  fb^{-1}.

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Equilibrium sorption studies of anionic species of arsenite, As(III) ions and arsenate As(V) ions onto two biosorbents, namely, chitosan and nanochitosan, have been investigated and compared. The results and trends in the sorption behavior are novel, and we have observed during the sorption process of the As(III) and As(V) on chitosan, a slow process of desorption occurred after an initial maximum adsorption capacity was achieved, before reaching a final but lower equilibrium adsorption capacity. The same desorption trend, however, is not observed on nanochitosan.

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Selenium (Se) is an essential element and its biological activity is related to its speciation. It is also well-known that in excess it can cause teratogenesis in fish and birds. In this study we compared dietary toxicity of elemental selenium nanoparticles (SeNPs) with selenite and selenomethionine (Se-Met).

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Objective: The incidence of cases of older onset anorexia nervosa (AN) has increased in recent years. However, the literature on late-onset AN has been inconclusive. The goal of this study was to compare late-onset with early-onset cases of AN.

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Objective: Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis. This post hoc analysis evaluated patients receiving tofacitinib monotherapy or combination therapy, as well as those who switched from monotherapy to combination therapy (mono→combo) or vice versa (combo→mono) in long-term extension (LTE) studies.

Methods: Data were pooled from open-label LTE studies (ORAL Sequel (NCT00413699; ongoing; data collected 14 January 2016) and NCT00661661) involving patients who participated in qualifying index studies.

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We report emerging subtropical bimodal seasonality and alternating predominance of norovirus GII.4 and non-GII.4 genotypes in Hong Kong.

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Patterns of social contact between individuals are important for the transmission of many pathogens and shaping patterns of immunity at the population scale. To refine our understanding of how human social behaviour may change over time, we conducted a longitudinal study of Hong Kong residents. We recorded the social contact patterns for 1450 individuals, up to four times each between May 2012 and September 2013.

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With the discovery of graphene, significant research has focused on the synthesis, characterization, and applications of ultrathin materials. Graphene has also brought into focus other ultrathin materials composed of organics, polymers, inorganics, and their hybrids. Together, these ultrathin materials have unique properties of broad significance.

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By analyzing a case of total knee arthroplasty (TKA) in a knee with complex deformity and secondary osteoarthritis, we demonstrated the rationale of preoperative planning and the detail of intraoperative execution. The lady had right TKA with combined medial closing wedge femoral osteotomy, neutral wedge valgus derotational tibial osteotomy, fibular osteotomy, and quadriceplasty. Four months later, she had left TKA.

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Aim: Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). We assess the effect of tofacitinib + conventional synthetic disease-modifying anti rheumatic drugs (csDMARDs) on patient-reported outcomes in Chinese patients with RA and inadequate response to DMARDs.

Methods: This analysis of data from the Phase 3 study ORAL Sync included Chinese patients randomized 4 : 4 : 1 : 1 to receive tofacitinib 5 mg twice daily, tofacitinib 10 mg twice daily, placebo→tofacitinib 5 mg twice daily, or placebo→tofacitinib 10 mg twice daily, with csDMARDs.

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Background: Tuberculosis (TB) in the elderly remains a challenge in intermediate disease burden areas like Hong Kong. Given a higher TB burden in the elderly and limited impact of current case-finding strategy by patient-initiated pathway, proactive screening approaches for the high-risk group could be optimal and increasingly need targeted economic evaluations. In this study, we examined whether and under what circumstance the screening strategies are cost-effective compared with no screening strategy for the elderly at admission to residential care homes.

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This study examines the influence of building envelope features on interunit dispersion around multi-story buildings, when the presence of an upstream interfering building is also considered. Validated CFD methods in the steady-state RANS framework are employed. In general, the reentry ratios of pollutant from a source unit to adjacent units are mostly in the order of 0.

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A search for standard model production of four top quarks ( ) is reported using events containing at least three leptons ( ) or a same-sign lepton pair. The events are produced in proton-proton collisions at a center-of-mass energy of 13 at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9 .

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Events with no charged particles produced between the two leading jets are studied in proton-proton collisions at . The jets were required to have transverse momentum and pseudorapidity , and to have values of with opposite signs. The data used for this study were collected with the CMS detector during low-luminosity running at the LHC, and correspond to an integrated luminosity of 8 .

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A search for new physics in events with a Z boson produced in association with large missing transverse momentum at the LHC is presented. The search is based on the 2016 data sample of proton-proton collisions recorded with the CMS experiment at , corresponding to an integrated luminosity of 35.9 .

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A study of the associated production of a boson and a charm quark jet ( ), and a comparison to production with a quark jet ( ), in collisions at a centre-of-mass energy of 8 are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 , collected with the CMS detector at the CERN LHC.

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Four-lepton production in proton-proton collisions, , where or , is studied at a center-of-mass energy of 13 with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 .

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A search is presented for physics beyond the standard model, based on measurements of dijet angular distributions in proton-proton collisions at . The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 35.9 .

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A measurement is presented of the cross section in collisions at , using data recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of . The product of the inclusive cross section and branching fraction is measured to be , in agreement with the standard model expectation, computed at next-to-next-to-leading order accuracy in perturbative quantum chromodynamics. The measurement is used to validate new analysis techniques relevant for future measurements of lepton production.

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The nuclear modification factors of and mesons are measured in collisions at a centre-of-mass energy per nucleon pair of . The analysis is based on and data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464 and 28 , respectively. The measurements are performed in the dimuon rapidity range of as a function of centrality, rapidity, and transverse momentum ( ) from in the most forward region and up to 50 .

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Measurements are presented of the lifetimes of the , , , and hadrons using the decay channels , , , , , and . The data sample, corresponding to an integrated luminosity of 19.7 , was collected by the CMS detector at the LHC in proton-proton collisions at .

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