Review article: Venous thromboembolism after total joint replacement

published_or_final_versio

Acoustic Emission from Porous Collapse and Moving Dislocations in Granular Mg-Ho Alloys under Compression and Tension.

We identified heterogeneous Mg-Ho alloys as an ideal material to measure the most extensive acoustic emission spectra available. Mg-Ho alloys are porous and show a high density of dislocations, which slide under external tension and compression. These dislocations nucleate near numerous heterogeneities. Two mechanisms compete under external forcing in the structural collapse, namely collapsing holes and the movements of dislocations. Their respective fingerprints in acoustic emission (AE) measurements are very different and relate to their individual signal strengths. Porous collapse generates very strong AE signals while dislocation movements create more but weaker AE signals. This allows the separation of the two processes even though they almost always coincide temporarily. The porous collapse follows approximately mean-field behavior (ε = 1.4, τ' = 1.82, α = 2.56, x = 1.93, χ = 1.95) with mean field scaling fulfilled. The exponents for dislocation movement are greater (ε = 1.92, τ' = 2.44, α = 3.0, x = 1.7, χ = 1.42) and follows approximately the force integrated mean-field predictions. The Omori scaling is similar for both mechanisms. The Bath's law is well fulfilled for the porous collapse but not for the dislocation movements. We suggest that such 'complex' mixing behavior is dominant in many other complex materials such as (multi-) ferroics, entropic alloys and porous ferroelastics, and, potentially, homogeneous materials with the simultaneous appearance of different collapse mechanisms.We appreciate the support of the Natural Science Foundation of China (51320105014, 51621063) and 111 project 2.0 (BP2018008). EKHS is grateful to EPSRC (EP/P024904/1) and the Leverhulme trust (RPG-2012-564)

Perioperative antithrombotic management in joint replacement surgeries

Objectives To determine optimal perioperative antithrombotic management for patients with cardiac diseases undergoing joint replacement surgeries. Data sources MEDLINE and PubMed database search up to January 2013. Study selection Those dealing with perioperative antithrombotic management of patients undergoing orthopaedic operations, especially joint replacement, and also those undergoing general surgery. Various combinations of the following key words were used in our search: 'antiplatelet', 'antithrombotic', 'anticoagulant', 'coronary stent', 'perioperative', 'venous thromboembolism', 'cardiovascular', 'surgery', 'orthopaedic', 'knee replacement', 'hip replacement', 'joint replacement', and 'arthroplasty'. Data extraction Literature review, original articles, and best practice guidelines. Data synthesis Patients should be stratified according to their risk of developing arterial thromboembolism in order to decide the most appropriate perioperative antiplatelet or anticoagulant regimen for them. After recent coronary stenting, including bare-metal stents implanted within 6 weeks and drug-eluting stents implanted within 6 months, surgery should be deferred. For venous thromboembolism prophylaxis in patients already on aspirin, the dosage should be adjusted as necessary or additional low-molecular-weight heparin administered. Conclusion The perioperative management of patients with cardiac diseases in receipt of antithrombotic agents is based upon a delicate balance between the perceived risk of arterial thromboembolism and the perceived risk of perioperative bleeding. One must exercise good judgement in deciding the most appropriate perioperative antithrombotic regimen. Venous thromboembolism is also a common problem after joint replacement surgeries. For patients already on aspirin, optimal venous thromboembolism prophylaxis is still being debated.published_or_final_versio

Investigation on the Dispersal Characteristics of Liquid Breakup in Vacuum

This work presents an experimental study on the dispersal characteristics of a liquid jet ejecting into vacuum. The liquid breaking experiments of several kinds of liquid under different pressure and temperature conditions are carried out in a flash chamber. The stability of the jet and the sizes of the droplets or the icing particles formed during liquid flashing dispersing are analyzed. The influences of the superheat degree, spray velocity, and the mass of the volatile liquid mixing in the nonvolatile liquid on these characteristics are discussed. Moreover, the applicability of the two definitions of superheat degree is discussed. The results show that the superheat degree is an important parameter influencing the pattern of the breaking liquid, and the jet velocity has a large influence on the distribution of particle sizes. In addition, mixing some volatile liquid with nonvolatile liquid can enhance the dispersion of the latter

Restoration of Humeral Bone Stock Two Years After Internal Fixation of a Periprosthetic Fracture with a Loose Stem

published_or_final_versio

Impact of glycaemic control on circulating endothelial progenitor cells and arterial stiffness in patients with type 2 diabetes mellitus

Topics: Basic science, translational and clinical researchPoster PresentationThis journal supplement contains abstracts from the 17th MRC; Dept. of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong KongINTRODUCTION: Patients with type 2 diabetes mellitus (DM) have increased risk of endothelial dysfunction and arterial stiffness. Levels of circulating endothelial progenitor cells (EPCs) are also reduced in hyperglycaemic states. However, the relationships between glycaemic control, levels of EPCs and arterial stiffness are unknown. METHODS: We measured circulating EPCs and …published_or_final_versionThe 17th Medical Research Conference (MRC), Department of Medicine, University of Hong Kong, Hong Kong, 14 January 2012. In Hong Kong Medical Journal, 2012, v. 18 suppl. 1, p. 63, abstract no. 10

X-ray radiation and runaway electron beams generated during discharges in atmospheric-pressure air at rise times of voltage pulse of 500 and 50 ns

The parameters of X-ray radiation and runaway electron beams (RAEBs) generated at long-pulse discharges in atmospheric-pressure air were investigated. In the experiments, high-voltage pulses with the rise times of 500 and 50 ns were applied to an interelectrode gap. The gap geometry provided non-uniform distribution of the electric field strength. It was founded that at the voltage pulse rise time of 500 ns and the maximum breakdown voltage Um for 1 cm-length gap, a duration [full width at half maximum (FWHM)] of a RAEB current pulse shrinks to 0.1 ns. A decrease in the breakdown voltage under conditions of a diffuse dischargeleads to an increase in the FWHM duration of the electron beam current pulse up to several nanoseconds. It was shown that when the rise time of the voltage pulse is of 500 ns and thediffuse discharge occurs in the gap, the FWHM duration of the X-ray radiation pulse canreach≈100 ns. It was established that at a pulse-periodic diffuse discharge fed by high-voltage pulses with the rise time of 50 ns, an energy of X-ray quanta and their number increase with increasing breakdown voltage. Wherein the parameter Um/pd is saved

Harvesting convalescent plasma for hyperimmune intravenous globulin production: a multicentre randomised double-blind controlled trial for treatment of patients with serious S-OIV H1N1 infection

Poster Presentations: Emerging / Infectious Diseases: abstract no. P107-Ab0089Symposium Theme: Translating Health Research into Policy and Practice for Health of the Populationpublished_or_final_versio

Harvesting convalescent plasma for hyperimmune intravenous globulin production: a multicentre randomised double-blind controlled trial for treatment of patients with serious S-OIV H1N1 infection

Poster Presentations: Emerging / Infectious Diseases: abstract no. P107-Ab0089Symposium Theme: Translating Health Research into Policy and Practice for Health of the Populationpublished_or_final_versio

Supershort avalanche electron beam in SF6 and krypton

Runaway electrons play an important role in the avalanche formation in nanosecond- and subnanosecond- pulse discharges. In this paper, characteristics of a supershort avalanche electron beam (SAEB) generated at the subnanosecond and nanosecond breakdown in sulfur hexafluoride (SF6 ) in an inhomogeneous electric field were studied. One pulser operated at negative polarity with voltage pulse amplitude of ˜130 kV and rise time of 0.3 ns. The other pulser operated at negative polarity with voltage pulse amplitude of 70 kV and rise time of ˜1.6 ns . SAEB parameters in SF6 are compared with those obtained in krypton (Kr), nitrogen (N2 ), air, and mixtures of SF6 with krypton or nitrogen. Experimental results showed that SAEB currents appeared during the rise-time of the voltage pulse for both pulsers. Moreover, amplitudes of the SAEB current in SF6 and Kr approximately ranged from several to tens of milliamps at atmospheric pressure, which were smaller than those in N2 and air (ranging from hundreds of milliamps to several amperes). Furthermore, the concentration of SF6 additive could significantly reduce the SAEB current in N2-SF6 mixture, but it slightly affected the SAEB current in Kr -SF6 mixture because of the atomic/molecular ionization cross section of the gas had a much greater impact on the SAEB current rather than the electronegativity