Resuming elective hip and knee arthroplasty after the first phase of the SARS-CoV-2 pandemic: the European Hip Society and European Knee Associates recommendations

The Covid-19 pandemic has disrupted health care systems all over the world. Elective surgical procedures have been postponed and/or cancelled. Consensus is, therefore, required related to the factors that need to be in place before elective surgery, including hip and knee replacement surgery, which is restarted. Entirely new pathways and protocols need to be worked out. Methods A panel of experts from the European Hip Society and European Knee Association have agreed to a consensus statement on how to reintroduce elective arthroplasty surgery safely. The recommendations are based on the best available evidence and have been validated in a separate survey. Results The guidelines are based on five themes: modification and/or reorganisation of hospital wards. Restrictions on orthopaedic wards and in operation suite(s). Additional disinfection of the environment. The role of ultra-clean operation theatres. Personal protective equipment enhancement. Conclusion Apart from the following national and local guidance, protocols need to be put in place in the patient pathway for primary arthroplasty to allow for a safe retur

Recommendations for resuming elective hip and knee arthroplasty in the setting of the SARS‑CoV‑2 pandemic: the European Hip Society and European Knee Associates Survey of Members

The COVID-19 pandemic has disrupted the health care system around the entire globe. A consensus is needed about resuming total hip and knee procedures. The European Hip Society (EHS) and the European Knee Association (EKA) formed a panel of experts that have produced a consensus statement on how the safe re-introduction of elective hip and knee arthroplasty should be undertaken. Methods A prospective online survey was done among members of EHS and EKA. The survey consisted of 27 questions. It includes basic information on demographics and details the participant’s agreement with each recommendation. The participant could choose among three options (agree, disagree, abstain). Recommendations focussed on pre-operative, perioperative, and post-operative handling of patients and precautions. Results A total of 681 arthroplasty surgeons participated in the survey, with 479 fully completing the survey. The participants were from 44 countries and 6 continents. Apart from adhering to National and Local Guidelines, the recommendations concerned how to make elective arthroplasty safe for patients and staf. Conclusion The survey has shown good-to-excellent agreement of the participants with regards to the statements made in the recommendations for the safe return to elective arthroplasty following the frst wave of the COVID-19 pandemi

Photoinduced Electron and Energy Transfer in Covalently Linked Supramolecular Systems

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Second-Sphere Donor-Acceptor Interactions in Excited States of Coordination Compounds. Ruthenium(II) Bipyridine Cyano Complexes

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Excited-State Charge Recombination in a Ru(II)-Cr(III) Polynuclear Complex

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Crossover from Metal-Centered to Ligand- Centered Emission in Rh(III) Polypyridine Cmplexes. Rh(phen)2(NH3)Cl2+, Rh(phen)2(NH3)23+, Rh(phen)2(CN)2+

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pCarborane-bridged Bipyridine Ligands for Energy Transfer Between Two Iridium Centers

Two iridium(III) complexes displaying for one a high HOMO-LUMO gap and for the other a weaker gap were linked in a controlled and logical manner to closo-p-carborane spacers. The bridging ligand is composed of 5-ethynyl-2,2'-bipyridine units, and the peripherical Ir-ligands are orthometalated 2',4'-difluoro-2-phenylpyridine (dfppy) (lambda(abs) at 400 rim for the "Ir(dfppy)(2)(bpy')") for the energy donor fragment and dibenzo[a,c]phenazine (dbpz) (lambda(abs) at 525 nm for "Ir(dbpz)(2)(bpy')") for the energy acceptor fragment. Redo; spectroscopic, and photophysical properties for models and the donor-carborane-acceptor complex were determined. Efficient energy transfer from the "Ir(dfppy)(2)(bpy')" moiety to the "Ir(dbpz)(2)(bpy')" fragment is occurring with a rate constant of 3.3 X 10(8) s(-1) despite weak electronic coupling through the inert p-carborane spacer. From flash photolysis experiments it is shown that, by excitation of the donor, a low lying triplet state localized on the acceptor bridging ligand side is formed which decays by conversion to the (MLCT)-M-3 of the acceptor fragment which phosphoresces at 644 nm

Photochemistry and Photophysics of Coordination Compounds: Rhodium

Rhodium(III) polypyridine complexes and their cyclometalated analogues display photophysical properties of considerable interest, both from a fundamental viewpoint and in terms of the possible applications. In mononuclear polypyridine complexes, the photophysics and photochemistry are determined by the interplay between LC and MC excited states, with relative energies depending critically on the metal coordination environment. In cyclometalated complexes, the covalent character of the C – Rh bonds makes the lowest excited state classification less clear cut, with strong mixing of LC, MLCT, and LLCT character being usually observed. In redox reactions, Rh(III) polypyridine units can behave as good electron acceptors and strong photo-oxidants. These properties are exploited in polynuclear complexes and supramolecular systems containing these units. In particular, Ru(II)-Rh(III) dyads have been actively investigated for the study of photoinduced electron transfer, with specific interest in driving force, distance, and bridging ligand effects. Among systems of higher nuclearity undergoing photoinduced electron transfer, of particular interest are polynuclear complexes where rhodium dihalo polypyridine units, thanks to their Rh(III)/Rh(I) redox behavior, can act as twoelectron storage components. A large amount of work has been devoted to the use of Rh(III) polypyridine complexes as intercalators for DNA. In this role, they have proven to be very versatile, being used for direct strand photocleavage marking the site of intercalation, to induce long-distance photochemical damage or dimer repair, or to act as electron acceptors in long-range electron transfer processes

A Selective Metal-Mediated Approach for the Efficient Self-Assembling of Multi-Component Photoactive Systems

We report on the efficient use of different coordinative affin- ities to quantitatively construct a three-component multi- chromophore system containing one free-base porphyrin, one aluminium(III) monopyridylporphyrin, and one ruth- enium(II) tetraphenylporphyrin in a single step. The Al III monopyridylporphyrin plays the pivotal role in directing the correct self-assembly process, and it behaves as the antenna unit for the photoinduced processes of interest. A two-com- ponent system, containing the same free-base porphyrin and one aluminium(III) tetraphenylporphyrin, was prepared for comparative studies. Both systems are remarkably stable in chlorinated solutions. Their photophysical behaviour was studied in detail by stationary and time-resolved emission techniques. In the two-component system, fast and efficient singlet energy transfer from the Al\u2013porphyrin to the free- base porphyrin is observed; in the three-component system, upon excitation of the Al\u2013porphyrin, a fast (minor of 250 ps) electron transfer process from the Ru\u2013porphyrin to the aluminium\u2013porphyrin is observed