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The COVID-19 pandemic highlighted some potential limitations of transmission-based precautions. The distinction between transmission through large droplets vs aerosols, which have been fundamental concepts guiding infection control measures, has been questioned, leading to considerable variation in expert recommendations on transmission-based precautions for COVID-19. Furthermore, the application of elements of contact precautions, such as the use of gloves and gowns, is based on low-quality and inconclusive evidence and may have unintended consequences, such as increased incidence of healthcare-associated infections and spread of multidrug-resistant organisms. These observations indicate a need for high-quality studies to address the knowledge gaps and a need to revisit the theoretical background regarding various modes of transmission and the definitions of terms related to transmission. Further, we should examine the implications these definitions have on the following components of transmission-based precautions: (i) respiratory protection, (ii) use of gloves and gowns for the prevention of respiratory virus infections, (iii) aerosol-generating procedures and (iv) universal masking in healthcare settings as a control measure especially during seasonal epidemics. Such a review would ensure that transmission-based precautions are consistent and rationally based on available evidence, which would facilitate decision-making, guidance development and training, as well as their application in practice.

A B S T R A C T Multinational surveillance programmes for methicillin-resistant Staphylococcus aureus (MRSA) are dependent on national structures for data collection. This study aimed to capture the diversity of national MRSA surveillance programmes and to propose a framework for harmonisation of MRSA surveillance. The International Society of Antimicrobial Chemotherapy (ISAC) MRSA Working Group conducted a structured survey on MRSA surveillance programmes and organised a webinar to discuss the programmes' strengths and challenges as well as guidelines for harmonisation. Completed surveys represented 24 MRSA surveil-lance programmes in 16 countries. Several countries reported separate epidemiological and microbiolog-ical surveillance. Informing clinicians and national policy-makers were the most common purposes of surveillance. Surveillance of bloodstream infections (BSIs) was present in all programmes. Other invasive infections were often included. Three countries reported active surveillance of MRSA carriage. Method-ology and reporting of antimicrobial susceptibility, virulence factors, molecular genotyping and epidemi-ological metadata varied greatly. Current MRSA surveillance programmes rely upon heterogeneous data collection systems, which hampers international epidemiological monitoring and research. To harmonise MRSA surveillance, we suggest improving the integration of microbiological and epidemiological data, im-plementation of central biobanks for MRSA isolate collection, and inclusion of a representative sample of skin and soft-tissue infection cases in addition to all BSI cases.Crown Copyright (c) 2022 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Multinational surveillance programmes for methicillin-resistant Staphylococcus aureus (MRSA) are dependent on national structures for data collection. This study aimed to capture the diversity of national MRSA surveillance programmes and to propose a framework for harmonisation of MRSA surveillance. The International Society of Antimicrobial Chemotherapy (ISAC) MRSA Working Group conducted a structured survey on MRSA surveillance programmes and organised a webinar to discuss the programmes’ strengths and challenges as well as guidelines for harmonisation. Completed surveys represented 24 MRSA surveillance programmes in 16 countries. Several countries reported separate epidemiological and microbiological surveillance. Informing clinicians and national policy-makers were the most common purposes of surveillance. Surveillance of bloodstream infections (BSIs) was present in all programmes. Other invasive infections were often included. Three countries reported active surveillance of MRSA carriage. Methodology and reporting of antimicrobial susceptibility, virulence factors, molecular genotyping and epidemiological metadata varied greatly. Current MRSA surveillance programmes rely upon heterogeneous data collection systems, which hampers international epidemiological monitoring and research. To harmonise MRSA surveillance, we suggest improving the integration of microbiological and epidemiological data, implementation of central biobanks for MRSA isolate collection, and inclusion of a representative sample of skin and soft-tissue infection cases in addition to all BSI cases., SCOPUS: ar.j, info:eu-repo/semantics/published

Background Antibiotic resistance is a leading global public health concern and antibiotic use is a key driver. Effective interventions are needed to target key stakeholders, including general practitioners (GPs). In Malta, little is known about factors that influence GPs' antibiotic prescribing, making it challenging to implement targeted interventions. We therefore aimed to explore GPs' understanding of antibiotic use and resistance, and describe their perceived barriers and facilitators to prudent antibiotic prescribing for acute respiratory tract infections in Malta. Methods Face-to-face individual semi-structured interviews were held with a quota sample of 20 GPs in 2014. Interviews were audio recorded and transcribed verbatim, and later analysed iteratively using manifest and latent content analysis. Findings were collated in a socioecological model to depict how GPs as individuals are embedded within larger social systems and contexts, and how each component within this system impacts their prescribing behaviour. Findings We found that GPs' antibiotic prescribing decisions are complex and impacted by numerous barriers and facilitators at the individual, interpersonal, organisational, community, and public policy level. Predominant factors found to impact GPs' antibiotic prescribing included not only intrinsic GP factors such as knowledge, awareness, experience, and misconceptions, but also several external factors. At the interpersonal level, GPs' perceived patient demand and behaviour to be a persistent issue that impacts their prescribing decisions. Similarly, some GPs found pressure from drug reps to be concerning despite being considered an important source of information. Organisational and public policy-level issues such as lack of access to relevant antibiotic prescribing guidelines and current antibiotic resistance data from the community, were also considered major barriers to appropriate antibiotic prescribing. Utilisation of diagnostic testing was f

The response from steep and breaking waves for a monopile structure is investigated by analysis of experimental results and by application of numerical models for six irregular sea states. The experimental monopile was designed to reproduce the first and second natural frequencies of the NREL 5 MW reference monopile wind turbine. The measured response is reproduced in a finite element model using the Morison equation extended to full Lagrangian acceleration with second-order wave kinematics, and with fully non-linear kinematics and the axial divergence term. For the fully nonlinear wave kinematics, the additional point forces of Rainey and Kristiansen & Faltinsen (KF) are further added. In the latter model, the kinematics at the still water level are obtained by Taylor expansion of the kinematics from the free surface. The shear force at the sea bed and the structural accelerations are next compared between the force models and the experimental data. Among the findings are that the extreme force events are generally smallest for the second-order Morison approach, followed by the extended Morison model, and then the Rainey and KF model which produce similar results. While the total accelerations are found to generally match the measurements with fair accuracy, a modal decomposition shows that all models overpredict the response at the first eigenfrequency and underpredict it at the second eigenfrequency for extreme events. The latter is linked to the missing description of slamming loads in the modelling approach. The point force models of Rainey and KF are found to give quite similar results for the extreme events, the reasons for which are demonstrated by regular wave analysis.

BACKGROUND: Antibiotic use is a major driver of antibiotic resistance. Although delayed antibiotic prescription is a recommended strategy to reduce antibiotic use, practices vary; it appears less commonly used in southern European countries where antibiotic consumption is highest. Despite these variations, few qualitative studies have explored general practitioners' perceptions of delayed antibiotic prescription. We therefore aimed to explore and describe the perceptions of delayed antibiotic prescription for respiratory tract infections among general practitioners in Malta. METHODS: This qualitative phenomenographic study was conducted in Malta. A semi-structured interview guide was developed in English, pilot tested and revised accordingly. Interview topics included views on antibiotic resistance, antibiotic use and delayed antibiotic prescription for respiratory tract infections, and barriers and facilitators to antibiotic prescription. Individual, face-to-face interviews were held in 2014 with a quota sample of 20 general practitioners and transcribed verbatim. Data were subsequently analysed using a phenomenographic approach. FINDINGS: General practitioners perceived delayed antibiotic prescription in five qualitatively different ways: (A) "The Service Provider"-maintaining a good general practitioner-patient relationship to retain patients and avoid doctor-shopping, (B) "The Uncertainty Avoider"-reaching a compromise and providing treatment just in case, (C) "The Comforter"-providing the patient comfort and reassurance, (D) "The Conscientious Practitioner"-empowering and educating patients, and limiting antibiotic use, and (E) "The Holder of Professional Power"-retaining general practitioner responsibility by employing a wait-and-see approach. Although general practitioners were largely positive towards delayed antibiotic prescription, not all supported the strategy; some preferred a wait-and-see approach with follow-up. Many delayed antibiotic prescription us

Evolutionary mechanisms underlying innovation of cell types have remained largely unclear. In multicellular eukaryotes, the evolutionary molecular origin of sperm differentiation is unknown in most lineages. Here, we report that in algal ancestors of land plants, changes in the DNA-binding domain of the ancestor of the MYB transcription factor DUO1 enabled the recognition of a new cis-regulatory element. This event led to the differentiation of motile sperm. After neo-functionalization, DUO1 acquired sperm lineage-specific expression in the common ancestor of land plants. Subsequently the downstream network of DUO1 was rewired leading to sperm with distinct morphologies. Conjugating green algae, a sister group of land plants, accumulated mutations in the DNA-binding domain of DUO1 and lost sperm differentiation. Our findings suggest that the emergence of DUO1 was the defining event in the evolution of sperm differentiation and the varied modes of sexual reproduction in the land plant lineage.

This paper describes a state-of-the-art model of the DTU 10MW Reference Wind Turbine mounted on the LIFES50+ OO-Star Wind Floater Semi 10MW floating substructure, implemented in FAST v8.16. The purpose of this implementation is to serve as a reference for different activities carried out within the LIFES50+ project. Attention is given to the changes necessary to adapt the numerical model of the onshore DTU 10MW Reference Wind Turbine to a floating foundation. These changes entail controller, tower structural properties, floating substructure hydrodynamics and mooring system. The basic DTU Wind Energy controller was tuned in order to avoid the “negative damping” problem. The flexible tower was extended down to the still water level to capture some of the floater flexibility. The mooring lines were implemented in MoorDyn, which includes dynamic effects and allows the user to define multi-segmented mooring lines. Hydrodynamics were precomputed in the radiation-diffraction solver WAMIT, while viscous drag effects are captured by the Morison drag term. The floating substructure was defined in HydroDyn to approximate the main drag loads on the structure, keeping in mind that only circular members can be modelled. A first set of simulations for system identification purposes was carried out to assess system properties such as natural frequencies and response to regular waves. The controller was tested in a simulation with uniform wind ranging from cut-in to cut-out wind speed. A set of simulations in stochastic wind and waves was carried out to characterize the global response of the floating wind turbine. The results are presented and the main physical phenomena are discussed. The model will form the basis for further studies in the LIFES50+ project and is available for free use.

A model for Quick Load Analysis of Floating wind turbines (QuLAF) is presented and validated here. The model is a linear, frequency-domain, efficient tool with four planar degrees of freedom: floater surge, heave, pitch and first tower modal deflection. The model relies on state-of-the-art tools from which hydrodynamic, aerodynamic and mooring loads are extracted and cascaded into QuLAF. Hydrodynamic and aerodynamic loads are pre-computed in WAMIT and FAST, respectively, while the mooring system is linearized around the equilibrium position for each wind speed using MoorDyn. An approximate approach to viscous hydrodynamic damping is developed, and the aerodynamic damping is extracted from decay tests specific for each degree of freedom. Without any calibration, the model predicts the motions of the system in stochastic wind and waves with good accuracy when compared to FAST. The damage-equivalent bending moment at the tower base is estimated with errors between 0.2% and 11.3% for all the load cases considered. The largest errors are associated with the most severe wave climates for wave-only conditions and with turbine operation around rated wind speed for combined wind and waves. The computational speed of the model is between 1300 and 2700 times faster than real time.

Evolutionary mechanisms underlying innovation of cell types have remained largely unclear. In multicellular eukaryotes, the evolutionary molecular origin of sperm differentiation is unknown in most lineages. Here, we report that in algal ancestors of land plants, changes in the DNA-binding domain of the ancestor of the MYB transcription factor DUO1 enabled the recognition of a new cis-regulatory element. This event led to the differentiation of motile sperm. After neo-functionalization, DUO1 acquired sperm lineage-specific expression in the common ancestor of land plants. Subsequently the downstream network of DUO1 was rewired leading to sperm with distinct morphologies. Conjugating green algae, a sister group of land plants, accumulated mutations in the DNA-binding domain of DUO1 and lost sperm differentiation. Our findings suggest that the emergence of DUO1 was the defining event in the evolution of sperm differentiation and the varied modes of sexual reproduction in the land plant lineage.

In this project by the University of Stuttgart, DTU Wind Energy and CENER, a real-time blade-pitch control system was implemented on a scaled model in a combined wind-and-wave tank. A simplified low-order simulation model including aerodynamics, hydrodynamics, mooring dynamics and structural dynamics was used to design the controller. Some effort has been made to investigate the influence of different gain scheduling methodologies of the collective blade-pitch controller on the dynamic behavior of the floating wind turbine. The issue relating to the negative aerodynamic damping is also investigated in order to find out whether the effects seen in simulation models can be equally reproduced by model tests. Additionally, wind and wave-induced responses with different gain scheduling methodologies and the difference to the tests without blade-pitch control are discussed. A solution for the hardware implementation of the real-time controller has been introduced. The developed controller is proven to function throughout the test campaign, which also proves the reliability of the simplified simulation model for controller design. It has been shown that with the low-Reynolds rotor it is possible to control the rotor speed at Froude-scaled frequencies by actuating the blade pitch angle.

Results of a test campaign for a floating wind turbine in simultaneous wind and wave forcing at scale 1:60 are presented. The floater is the Triple Spar floater, a hybrid between a spar buoy and a semi submersible tri-floater, tested here for the first time. The turbine is a model scale version of the DTU 10 MW reference wind turbine, which, also for the first time, is tested with active blade pitch control. The tests focus on the effects of aerodynamic damping and interaction effects between the wind forcing, wave forcing and the blade pitch control algorithm. Special focus is devoted to the instability of the platform pitch natural mode, that can occur if a standard land-based controller is applied.

This paper summarizes the findings from Phase Ib of the Offshore Code Comparison, Collaboration, Continued with Correlation (OC5) project. OC5 is a project run under the International Energy Agency (IEA) Wind Research Task 30, and is focused on validating the tools used for modelling offshore wind systems through the comparison of simulated responses of select offshore wind systems (and components) to physical test data. For Phase Ib of the project, simulated hydrodynamic loads on a flexible cylinder fixed to a sloped bed were validated against test measurements made in the shallow water basin at the Danish Hydraulic Institute (DHI) with support from the Technical University of Denmark (DTU). The first phase of OC5 examined two simple cylinder structures (Phase Ia and Ib) to focus on validation of hydrodynamic models used in the various tools before moving on to more complex offshore wind systems and the associated coupled physics. Verification and validation activities such as these lead to improvement of offshore wind modelling tools, which will enable the development of more innovative and costeffective offshore wind designs. (C) 2016 The Authors. Published by Elsevier Ltd.

This paper presents tests on a 1:60 version of the DTU 10MW wind turbine mounted on a tension leg platform and their numerical reproduction. Both the experimental setup and the numerical model are Froude-scaled, and the dynamic response of the floating wind turbine to wind and waves is compared in terms of motion in the six degrees of freedom, nacelle acceleration and mooring line tension. The numerical model is implemented in the aero-elastic code Flex5, featuring the unsteady BEM method and the Morison equation for the modelling of aerodynamics and hydrodynamics, respectively. It was calibrated with the tests by matching key system features, namely the steady thrust curve and the decay tests in water. The calibrated model is used to reproduce the wind-wave climates in the laboratory, including regular and irregular waves, with and without wind. The model predictions are compared to the measured data, and a good agreement is found for surge and heave, while some discrepancies are observed for pitch, nacelle acceleration and line tension. The addition of wind generally improves the agreement with test results. The aerodynamic damping is identified in both tests and simulations. Finally, the sources of the discrepancies are discussed and some improvements in the numerical model are suggested in order to obtain a better agreement with the experiments.

Designing floating substructures for the next generation of 10MW and larger wind turbines has introduced new challenges in capturing relevant physical effects in dynamic simulation tools. In achieving technically and economically optimal floating substructures, structural flexibility may increase to the extent that it becomes relevant to include in addition to the standard rigid body substructure modes which are typically described through linear radiation-diffraction theory. This paper describes a method for the inclusion of substructural flexibility in aero-hydro-servo-elastic dynamic simulations for large-volume substructures, including wave-structure interactions, to form the basis of deriving sectional loads and stresses within the substructure. The method is applied to a case study to illustrate the implementation and relevance. It is found that the flexible mode is significantly excited in an extreme event, indicating an increase in predicted substructure internal loads.

In the present paper the accuracy of three numerical models for a scaled 10MW TLP wind turbine is assessed by comparison with test data. The three models present different levels of complexity, and therefore different degrees of accuracy can be expected. A set of load cases including irregular and focused waves is run in the three models, where only wave loads are considered. The simulation results are compared against the test data, and the numerical models are assessed based on their ability to reproduce the test results. Finally, the possibility of enhancing the simple model by using the advanced models is discussed. (C) 2016 The Authors. Published by Elsevier Ltd.

This study continues [1] the examination of the long-term global response of a floating vertical axis wind turbine (VAWT) situated off the Portuguese coast in the Atlantic Ocean. The VAWT, which consists of a 5-MW 3-bladed H-type rotor developed as part of the EU-FP7 H2OCEAN project, is assumed to be mounted on the OC4 semi-submersible floating platform. Adding a non-operational load case (wind speed ~35m/s), the sea states identified are used to carry out coupled dynamics simulations using the FloVAWT design tool, for which an improved wave elevation and relative force/moment time signals approach is adopted, as well as also taking into account the drag generated by the wind turbine tower. Short-term turbine load and platform motion statistics are established for individual sea states that are analysed. The long-term reliability yields estimates of 50-year loads and platform motions that takes into consideration response statistics from the simulations as well as the metocean (wind-wave) data and distributions. The results show that it is not necessarily the load cases associated with the highest wind speed that lead to the highest displacements and tensions in the mooring lines; differences among the highest values in some load cases are too similar to establish which one should be considered in a conceptual/preliminary design phase. Also, the aerodynamic drag model needs to be further developed to improve its accuracy. These results and insights contribute to the development of improved floating VAWT design guidelines for reducing the cost of offshore wind energy generation.

DeepWind has been presented as a novel floating offshore wind turbine concept with cost reduction potentials. Twelve international partners developed a Darrieus type floating turbine with new materials and technologies for deep-sea offshore environment. This paper summarizes results of the 5 MW DeepWind conceptual design. The concept was evaluated at the Hywind test site, described on its few components, in particular on the modified Troposkien blade shape and airfoil design. The feasibility of upscaling from 5 MW to 20 MW is discussed, taking into account the results from testing the Deepwind floating 1 kW demonstrator. The 5 MW simulation results, loading and performance are compared to the OC3-NREL 5 MW wind turbine. Finally the paper elaborates the conceptual design on cost modelling.

This paper presents the experiences and challenges with concurrently carrying out numerical model development, integrated simulations and design of a novel floating vertical axis wind turbine, the DeepWind concept. The floating VAWT modelling capabilities of the aero-hydro-elastic HAWC2 simulation tool are briefly described and the design approach adopted for such a challenging project was to independently design subsystems in parallel, apart from essential design specifications. Instability issues encountered when integrating all subsystems in the unified numerical model, in particular blade edgewise and controller instabilities, are presented and efforts to alleviate such issues are detailed. A multidisciplinary design and optimization approach is proposed to eliminate these issues and accelerate future design cycles.

This study continues [1] the examination of the long-term global response of a floating vertical axis wind turbine (VAWT) situated off the Portuguese coast in the Atlantic Ocean. The VAWT, which consists of a 5-MW 3-bladed H-type rotor developed as part of the EU-FP7 H2OCEAN project, is assumed to be mounted on the OC4 semi-submersible floating platform. Adding a non-operational load case (wind speed 35m/s), the sea states identified are used to carry out coupled dynamics simulations using the FloVAWT design tool, for which an improved wave elevation and relative force/moment time signals approach is adopted, as well as also taking into account the drag generated by the wind turbine tower. Short-term turbine load and platform motion statistics are established for individual sea states that are analysed. The long-term reliability yields estimates of 50-year loads and platform motions that takes into consideration response statistics from the simulations as well as the metocean (wind-wave) data and distributions. The results show that it is not necessarily the load cases associated with the highest wind speed that lead to the highest displacements and tensions in the mooring lines; differences among the highest values in some load cases are too similar to establish which one should be considered in a conceptual/preliminary design phase. Also, the aerodynamic drag model needs to be further developed to improve its accuracy. These results and insights contribute to the development of improved floating VAWT design guidelines for reducing the cost of offshore wind energy generation.

To estimate the proportion of methicillin-resistant Staphylococcus aureus (MRSA) isolates from humans that were sequence type (ST) 398, we surveyed 24 laboratories in 17 countries in Europe in 2007. Livestock-associated MRSA ST398 accounted for only a small proportion of MRSA isolates from humans; most were from the Netherlands, Belgium, Denmark, and Austria., SCOPUS: ar.j, info:eu-repo/semantics/published

Even as the NATO Secretary General alluded to the possible withdrawal of forces from Kosovo, critics are clamoring that no clear exit strategy exists. The unilateral declaration of independence by Kosovo in February 2008 puts this new nation at the crossroads and is a game changer for NATO. For the past ten years NATO, through KFOR, established a safe and secure environment within the country. Kosovo must evolve as a nation capable of sustaining itself without the dependency on international donors or a peacekeeping force to guarantee security. An objective analysis of the latest progress reports from Kosovo is warranted. This paper examines the impact PRTs would have in Kosovo, where no PRTs are operating. It demonstrates the viability of PRTs in Kosovo by comparing current developmental needs against demonstrated PRT civil-military capabilities. Finally, this paper draws conclusions concerning the current KFOR capabilities and recommends that PRTs deploy in-lieu of the Multination Task Forces currently operating in Kosovo as an exit strategy., A paper submitted to the Faculty of the Naval War College in partial satisfaction of the requirements of the Department of Joint Military Operations. The original document contains color images.