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Most of the floating wind turbine (FWT) sub-structure concepts are designed with long natural periods of the vertical motions to de-tune from the wave frequency range. The consequence is that the natural frequencies of heave, roll and pitch are excited by low frequency wave and wind loads. The paper focus is on the low frequency (LF) wave drift loads and the related heave and pitch responses of a semi-submersible type of FWT (12MW INO WINDMOOR). It presents several approaches to calculate the wave drift force coefficients and related forces in irregular waves, namely mean wave drift coefficients combined with Newman’s approximation, quadratic transfer functions (QTFs) neglecting the free surface integral from the 2nd order potential flow solution and QTFs based on the full 2nd order solution. The different approximations are used to perform nonlinear time domain simulations of the FWT motions and the results compared to the model test data (the model tests were performed in the ocean basin of SINTEF at a scale of 1:40). The LF damping of heave and pitch is represented by a linear and a quadratic damping coefficient identified from decay model tests. The coupled numerical solution requires a correct representation of the surge mode of motion. In this case, the wave drift forces are represented by empirical QTFs, while the LF damping includes a contribution from the calm water damping represented by a linear and a quadratic coefficient, together with a wave drift damping coefficient. The numerical results show a good agreement with the model test data in irregular waves when full QTFs are used to calculate the wave drift forces.

An accurate estimation of the low-frequency wave loads on floating wind turbines is important for design of mooring systems. In order to add wave drift viscous effects, to the potential flow loads from radiation/diffraction codes, one approach would be to use the drag term in Morison’s equation integrated to the instantaneous free surface. The aim of this study is to define the drag coefficients depending on distance to free surface and KC (Keulegan-Carpenter) number. A systematic series of CFD simulations of Stokes fifth order waves has been done for a fixed structure resembling the floating wind turbine structure studied in WINDMOOR project. Simulations are run with the CFD code STAR-CCM+. The structure is a tripod composed of three vertical columns joined at the bottom by pontoons and at the top by deck beams. As one of the steps towards the analysis of the whole structure, the sectional CFD forces on one of the columns is studied here. Morison mass and drag coefficients are determined for each cross section of the column from the CFD simulation. Obtained sectional coefficients and total forces are compared with the available experimental data in the literature for a circular cylinder. The possible interaction effects between the columns are investigated. Forces on the sections close to the free surface are addressed and the accuracy of the Morison formula for these sections is discussed.

Committee Mandate Concern for investigation and applications of ships, offshore structures and engineering equipment for ocean space utilization in the context of marine resource exploitation, human habitation and other marine infrastructure. Focus should be given to fluid-structure interaction associated with large marine structures and structural flexibility. Due consideration should be given to the comparison of modelling approaches, existing and emerging guidance & best practices. Introduction In the light of rising sea level, scarcity of land-based resources and increasingly populated coastal areas, interest of project developers and countries turns towards the ocean, exploring the possibilities of utilizing this space for various purposes. With the oceans covering roughly 70% of the Earth’s surface and more than half of the world’s population clustered in coastal areas, the oceans are a natural direction to turn to. Ocean Space Utilization (OSU), i.e., the use of ocean waters and/or the seabed for human activities, is by no means new. Shipping and fishing in ocean waters date back millennia. During the last century, aquaculture of seafood production developed into a global industry. Also, the seabed has provided minerals (mostly sand) as building material. Recently, the marine mining industry experienced a development from traditional sand dredging to deep sea mining for precious or rare mineral resources. The offshore oil and gas industry developed from first wooden platforms in the shallow coastal waters of the Gulf of Mexico to Floating Production Storage and Offloading systems and subsea equipment in more than 2000 m water depth offshore Brazil. More recently, the wind energy industry followed the steps of the oil and gas industry and moved from land-based installations first to shallow coastal waters with bottom-founded wind turbines and now starts developing offshore floating wind turbines for larger water depth and greater distances to shore. Marine Renewable Energies (MRE) including Wave Energy Converters (WEC), flow turbines for electricity production from ocean or tidal currents, and Ocean Thermal Energy Conversion (OTEC) are emerging. Another recent form of renewable energy production on the ocean are Offshore Floating Photovoltaic (OFPV) Installations (Karpouzoglou et al., 2020; Trapani & Millar, 2016; Trapani & Redón Santafé, 2015). Furthermore, marine infrastructure projects of floating airports (Suzuki, 2005), floating bridges and submerged tunnels (Moan & Eidem, 2020; Watanabe et al., 2015), floating oil storage terminals (Ueda, 2015; Zhang et al., 2020), floating logistics hubs/ports (Waals et al., 2018), a floating event stage (Koh and Lim, 2015), as well as even entire floating cities (Callebaut, 2015) are discussed in the literature. Eventually, recreational use and ocean research also belong to the broad field of Ocean Space Utilization. As an inventory of Ocean Space Utilization projects, this committee gathered as many OSU projects as possible in various stages (from concept study to commercial project) and from various fields in a project atlas based on Google maps. Offshore oil and gas projects are excluded from the atlas to prevent overloading it. Figure 1.1 shows a screenshot of the project atlas with a global overview of all projects. The projects can be grouped and color-coded by OSU field or by project status as shown in the two columns on the right of the figure. At the time of writing, this project atlas contained 235 projects. Even without offshore oil and gas projects, the energy field, comprising mainly offshore wind farms, dominates the list with 90 projects. Two other large fields of OSU are food production, i.e., mainly (offshore) aquaculture with 46 projects, and infrastructure projects (35) like floating bridges and airports. From the project list by field, it is apparent that there are many projects associated with more than one field. This signifies the new trend of multi-use ocean space utilization. An example for this multi-use is mussel farming within an offshore wind farm (see Edulis project in food & energy field). Regarding the project stage, the project entries range from mere concepts and research projects to fully operational structures. The database behind this project atlas contains more information on the individual projects with details on the field (use), project name and location, coordinates, the associated institution as well as a link for further information.

With the development of floating wind turbines comes the need for mooring systems suitable for shallow water depths. Compliance becomes challenging for mooring systems composed of chain and wire rope. Polyester ropes can improve compliance, but the even lower stiffness of nylon may further reduce mooring line loads. However, fatigue lifetime of nylon ropes has been limiting. This paper presents results of stiffness and fatigue tests on long lay polyester and nylon ropes and evaluates the performance of two mooring systems for a floating wind turbine. The fibre ropes’ complex stiffness behaviour is modelled by the Syrope model, with mooring analyses based on fully coupled time-domain simulations. Nylon ropes reduce the dynamic loads in the mooring system, particularly wave frequency loads. This improves the fatigue lifetime of all components, allowing a reduction of the chain cross-section area by 40% compared to the polyester-based mooring system. The long lay nylon ropes show excellent fatigue properties. With the reduced loading, the lifetime is longer for the nylon ropes than the polyester ropes. Ultimate loads are also reduced when using nylon, allowing reduction of the breaking load by 30%. This gives a thinner and lighter rope than the equivalent polyester rope.

Calculation of wave drift forces in the context of mooring analysis is usually performed by potential flow boundary element methods. For monohulls with large waterplane area, such as floating, production, storage and offloading vessels (FPSOs), the assumption is that heave and pitch damping is dominated by inviscid radiation of waves. The present study investigates the effects of heave and pitch wave frequency viscous damping on the horizontal wave drift forces of a FPSO. Experimental evidence indicates the presence of non-negligible viscous damping in case of moderate and severe seastates. Such observation is confirmed by computational fluid dynamic (CFD) simulations of forced harmonic motions with different periods and amplitudes. On a second step, a numerical analysis shows that the surge wave drift forces increase significantly at the low frequency range when realistic heave and pitch viscous damping is considered. The frequency range where standard potential flow calculations appear to underestimate wave drift forces coincides with the range where design seastates have most of the energy. Finally, the wave drift coefficients calculated with realistic additional viscous damping are compared with empirical coefficients identified from model test data. The identification procedure follows a second order signal analysis technique known as cross bi spectral analysis.

A number of incidents of wave-induced loss of position for dynamically positioned semi-submersible under normal operating conditions have occurred in the Norwegian offshore sector in recent years. A study has been carried out to seek their cause. One hypothesis for the cause has been slamming load from an extremely tall and steep wave that is not effectively counteracted by the DP system due to delays in signal filters and thruster response. Another cause could the loads from a train of tall and steep waves. A linear single-degree-of-freedom numerical model is made for a vessel with DP. The model is essential in that it represents the basic characteristics of the DP system: State observer/filter and feedback control. The model is used to calculate the frequency response and the impulse response of the dynamically positioned semi-submersible. By calculating extreme impulsive load based on published theory it is established that slamming will not cause great vessel excursion. Still, due to delays, the DP system gives more than twice as large excursion as a mass-spring-damper system with identical restoring stiffness and damping. Using an advanced model for vessel with DP, three-hour simulations of stochastic vessel response are carried out for five steep wave states of moderate significant height, The likely cause of large vessel excursion is found to be wave-drift. Due to additional viscous loads on the semi’s columns the wave-drift loads will be significantly larger than predicted with potential theory.

This paper presents a comparison study on wave drift models as well as corresponding low frequency (LF) drift motions for mooring analysis of a spread moored FPSO in moderate seastates with and without current. There are four wave drift force models applied in this study, including two numerical models from potential theory with Newman’s approximation and full quadratic transfer functions (QTFs), two combined models determined from cross bi-spectral (CBS) analysis of model test data and merged with two numerical potential flow wave drift force models at low and high frequencies, respectively. The comparison is performed in terms of both diagonal and off diagonals with constant difference frequency. The equations of motion are solved in the time domain with a fully coupled method, accounting for different wave drift forces models. Both the LF motion response spectra and the time domain series are presented and discussed. The LF damping is adjusted by comparing simulations to the corresponding model test data and tuning the results. The results show the underestimates of wave drift forces as well as the corresponding LF motions by second order potential flow theory, especially in the cases with current. Application of full QTFs can improve the simulation results in terms of phasing of LF responses.

State of the art ULS/ALS mooring analysis is based on potential flow calculated wave drift forces. However, it is acknowledged that higher order effects in steep sea states increase the wave drift forces as compared to the potential flow 2nd order models. This is the background for the EXWAVE 2 JIP where semi-empirical methods to correct wave drift forces were implemented and checked, which shows the significance of this problem to the industry. This publication aims at applying CFD simulations to better understand the physics of wave drift loads in steep sea states and to identify higher than 2nd order effects. Calculations are performed with a RANSE-VOF based CFD code and with a linear potential flow code for a floating production storage and offloading (FPSO) unit in deep water regular waves with three periods and three wave steepnesses. The vessel is restrained from moving to make a simple and a consistent comparison between the results from the two approaches. Comparisons for small amplitude waves provide an assessment of the quality of the CFD simulations, while increasing wave steepness conditions are used to identify higher than second order effects on the wave drift forces. CFD simulation resulting force time series are decomposed into mean value and harmonics by means of a Fourier analysis and compared against potential theory estimated mean and first order forces. The comparisons for small wave amplitudes show a good agreement, which proofs the correctness of the applied CFD setup. Further, the CFD results show an increasing trend of the mean wave forces normalized by the wave amplitude squared with increasing wave steepness for the two shorter wave periods. The trend is unclear for the longer wave period.

The purpose of the D1.6 Data Management Plan Year 2 is to provide an overview of all datasets collected and generated within the MooringSense project, and to define the consortium’s data management policy that will be implemented. This initial version of the Data Management Plan defines the general policy and approach to data management in MooringSense. It covers management issues related to both administrative and technical aspects (e.g. collection of data and metadata, publication and deposition of open data, repository compliance with the Open Access Infrastructure for Research in Europe- OpenAIRE). The MooringSense Data Management Plan follows the Horizon 2020 FAIR Data Management Plan (DMP) Template. It is intended to be a living document in which information will be made available on a finer level of granularity through updates as the implementation of the project progresses and when significant changes occur. In this regard, it summarises the intermediate results of the data collection activities that are being carried out. Next versions of the Data Management Plan will refine and enhance policy aspects and will go into more detail regarding the datasets collected and produced by the MooringSense project.

The paper presents calibration and validation of a time domain numerical model for mooring analysis of a spread moored FPSO in moderate seastates with and without current. The equations of motion are solved in the time domain with a fully coupled method, accounting for linear wave frequency (WF) radiation and diffraction, second order wave drift forces and nonlinear low frequency (LF) damping. The mooring system dynamics is solved by a FEM. Uncalibrated numerical models are based on input from the mooring system, vessel mass, radiation/diffraction analysis, decay tests and current coefficients. WF responses are very well predicted by standard radiation/diffraction linear analysis, therefore the focus is on the LF responses. LF motions are underpredicted by the uncalibrated numerical model. Calibration is performed by comparing simulations with model test data and adjusting hydrodynamic coefficients known to be affected by uncertainty. These include wave drift force coefficients and LF damping. Correction of the drift coefficients is based on empirical quadratic transfer functions (QTFs) identified from the test data by a nonlinear data analysis technique known as “cross-bi-spectral analysis”. The LF damping coefficients are then adjusted by matching low frequency surge and sway spectra from the model tests and from the simulations.

Model tests were performed with a model of the INO WINDMOOR 12 MW floating wind turbine in the Ocean Basin at SINTEF Ocean. The tests were done at a scale of 1:40. RealTime Hybrid Model testing was used for the modelling of the wind turbine rotor and aerodynamic loads. A subset of the results is analysed to study the influence of the wind on the platform motions, the acceleration at tower top, the loads at base of tower and the relative wave elevation. The study is based on the comparison of the quantities of interest for different tests with the same moderate sea-state but with different wind modelling: no wind, constant thrust force, turbulent wind of 11.5 m/s and turbulent wind of 25 m/s. The wind modelling has a minimal influence on the platform surge and pitch response in the wave-frequency range. On the other hand, the aerodynamic loads, including wind turbine controller dynamics and turbulent wind, has an important impact on the low-frequency surge and pitch response. The aerodynamic loads are important for the loads at tower base due to the dominance of the tower-RNA induced gravitational loads at low-frequency. Maximum relative wave elevation was found to be mainly dependent on the thrust induced mean pitch angle.

Design optimization of mooring systems is an important step towards the reduction of costs for the floating wind turbine (FWT) industry. Accurate prediction of slowly-varying horizontal motions is needed, but there are still questions regarding the most adequate models for low-frequency wave excitation, and damping, for typical FWT concepts. To fill this gap, it is fundamental to compare existing load models against model tests results. This paper describes a calibration procedure for a three-columns semi-submersible FWT, based on adjustment of a time-domain numerical model to experimental results in decay tests, and tests in waves. First, the numerical model and underlying assumptions are introduced. The model is then validated against experimental data, such that the adequate load models are chosen and adjusted. In this step, Newman’s approximation is adopted for the second-order wave loads, using wave drift coefficients obtained from the experiments. Calm-water viscous damping is represented as a linear and quadratic model, and adjusted based on decay tests. Additional damping from waves is then adjusted for each sea state, consisting of a combination of a wave drift damping component, and one component with viscous nature. Finally, a parameterization procedure is proposed for generalizing the results to sea states not considered in the tests.

Introduction: Acute kidney injury (AKI) has been described in Coronavirus Disease 2019 (COVID-19) patients and is considered a marker of disease severity and a negative prognostic factor for survival. In this study, the authors aimed to study the impact of transient and persistent acute kidney injury (pAKI) on in-hospital mortality in COVID-19 patients. Methods: This was a retrospective observational study of patients hospitalized with COVID-19 in the Department of Medicine of the Centro Hospitalar Universitario Lisboa Norte, Lisbon, Portugal, between March 2020 and August 2020. A multivariate analysis was performed to predict AKI development and in-hospital mortality. Results: Of 544 patients with COVID-19, 330 developed AKI: 166 persistent AKI (pAKI), 164 with transient AKI. AKI patients were older, had more previous comorbidities, had higher need to be medicated with RAAS inhibitors, had higher baseline serum creatine (SCr) (1.60 mg/dL vs 0.87 mg/dL), higher NL ratio, and more severe acidemia on hospital admission, and more frequently required admission in intensive care unit, mechanical ventilation, and vasopressor use. Patients with persistent AKI had higher SCr level (1.71 mg/dL vs 1.25 mg/dL) on hospital admission. In-hospital mortality was 14.0% and it was higher in AKI patients (18.5% vs 7.0%). CKD and serum ferritin were independent predictors of AKI. AKI did not predict mortality, but pAKI was an independent predictor of mortality, as was age and lactate level. Conclusion: pAKI was independently associated with in-hospital mortality in COVID-19 patients but its impact on long-term follow-up remains to be determined.

With the continuous growing of the aquaculture industry and increasingly limited fish farming sites at close to shore areas both in Norway and worldwide, there is a need to develop fish farms suitable for aquaculture production in typical offshore environments. For this purpose, SALMAR has developed and deployed the Ocean Farm 1 facility for offshore fish farming. The main purpose of this paper is to develop a reliable numerical model and investigate the motion responses of the Ocean Farm 1 structure in waves and current. The established numerical model consists of the Ocean Farm 1's frame structure (with rigidly-connected circular column components), the net and the mooring system. The hydrodynamic external loads and coefficients of the frame structure are obtained by using potential flow theory. The quadratic drag load on the individual circular columns of the frame structure is formulated by a given drag coefficient. The loads on the net are formulated by using the screen model, where the Reynold number dependent lift and drag forces are formulated as a function of the solidity ratio Sn of the net, relative inflow angle and velocity. The hydrodynamic loads on the mooring lines are formulated using the Morison's equation and the structural responses of the mooring lines are obtained using a nonlinear FE model. With the developed numerical model, time domain simulations are performed. The simulation results are firstly validated against measured data from the decay tests, current tests, and regular wave tests. After the validation, numerical simulations are performed in different irregular wave and current combined weather conditions and the obtained motion response of Ocean Farm 1 are discussed and compared with available measurement data.

Introduction: COVID-19 is currently a global health issue and an important cause of mortality. Chronic kidney disease (CKD) is one of the risk factors for infection, morbidity and mortality by SARS-CoV-2. In our study, we aimed to evaluate the clinical presentation and outcomes of CKD patients with COVID-19, as well as identify predictors of mortality. Methods: This was a retrospective study of CKD patients admitted in a tertiary-care Portuguese hospital between March and August of 2020. Variables were submitted to univariate and multivariate analysis to determine factors predictive of in-hospital mortality. Results: 130 CKD patients were analyzed (median age 73.9 years, male 60.0%). Hypertension (81.5%), cardiovascular disease (36.2%), and diabetes (54.6%) were frequent conditions. Cough, dyspnea, fever and respiratory failure were also common. Almost 60% had anemia, 50% hypoalbuminemia, 13.8% hyperlactacidemia and 17% acidemia. Mean serum ferritin was 1531 µg/L, mean CRP 8.3 mg/dL and mean LDH 336.9 U/L. Most patients were treated with lopinavir/ritonavir, hydroxychloroquine or corticosteroids and only 2 with remdesivir. Eighty percent had acute kidney injury and 16.2% required intensive care unit admission. The 34 patients who died were older and more likely to have heart failure. They had higher neutrophils/lymphocytes ratio, ferritin, lactate, and LDH levels. Multivariate analysis identified an association between older age [OR 1.1 (CI 1.01-1.24), p=0.027], higher ferritin [OR 1.0 (CI 1.00-1.00), p=0.009] and higher LDH levels [OR 1.0 (CI 1.00-1.01), p=0.014] and mortality. Conclusion: In our cohort of CKD patients with COVID-19, older age, higher ferritin, and higher LDH levels were independent risk factors for mortality.

This paper presents parameter sensitivity analysis for a FPSO numerical model updating. Generally, model test data are considered a better presentation of physical phenomena than its numerical counterpart. To minimize the discrepancy, model updating is of pragmatically importance. Model updating of a certain FPSO can be achieved by specific steps. In each step, the required properties of numerical model and test results are matched by means of tuning of the related parameters. To avoid inefficiency and physical meaning loss resulting from large modification of parameters which are insensitive to objective properties, parameter sensitivity analyses using the direct method are conducted in this paper. The investigated parameters mainly are the FPSO’s mooring line length, mooring line mass per unit length, mooring line cross-sectional area, fairlead position, FPSO hydrostatic stiffness, FPSO mass properties, linear and quadratic damping coefficients. According to the different stages of FPSO model updating, the objective functions are set to be the FPSO’s mooring line pretension, mooring system horizontal restoring force, the natural periods of the FPSO’s 6 degree of freedom motions and the standard deviation of motion response spectra under irregular waves.

This paper investigates three different approximations of the full Quadratic Transfer Function (QTF) for calculating horizontal plane second-order difference-frequency loads on FPSOs, namely Newman’s approximation, full QTF without free surface integral and the white-noise approximation. Second-order excitation loads obtained from approximated QTFs are compared in frequency-domain with those obtained by the full QTFs computed from second-order diffraction/radiation analysis in WADAM. The comparison is performed for a new-build FPSO in a range of water depths and environmental combinations. The full QTFs from second-order diffraction/radiation analysis are further compared to empirical QTFs as identified from cross bi-spectral analysis of model test results in irregular waves. A mesh convergence study is presented for calculating full QTFs by the near-field approach in a second-order diffraction/radiation analysis. The importance of including viscous damping in heave, roll and pitch is illustrated for the mean wave-drift force in surge and sway. FPSO motions and mooring line tensions from fully-coupled time-domain analysis in OrcaFlex is compared when using approximated QTFs and full QTFs from second-order diffraction/radiation analysis.

Prediction of shallow water low frequency (LF) motions of vessels in the context of mooring analysis is challenging. Model tests are often performed to calibrate and validate numerical models and, in this way, reduce the uncertainty. Model tests are part of the positioning system qualifying process. However, model tests also present challenges and uncertainties related to parasitic low frequency wave systems which are unavoidable in shallow water ocean basin conditions. The paper presents model tests with a ship moored in shallow water (20 m), the analysis and discussion of the test data and comparisons with numerical predictions. The focus is on the low frequency motions and related wave drift forces. The tests have been performed in harmonic waves, bi-harmonic waves and irregular seastates, including conditions with and without current. The first part of the study consists of analysing the wave field measured by a long array of wave sensors distributed along the ocean basin. The analysis provides split wave systems, namely the low frequency components including the bound wave, the incoming free parasitic wave, the reflected component and additional very long waves. The second part proposes a method to calibrate and validate mooring analysis numerical models, based on comparisons with model test data which includes the unavoidable effects from parasitic waves. Simulations of LF motions with the calibrated model show a good agreement with the measurements.

Model tests have been performed with four mobile offshore drilling units (MODUs) with the aim of identifying wave drift forces and low-frequency damping. The MODUs configuration is different, namely on the number and diameter of columns; therefore, the sample is representative of many of the existing concepts. The model scale is the same as well as the wave and current conditions. The experimental program includes irregular waves with systematic variations of the significant wave height, wave peak period, current velocity, and vessel heading. A nonlinear data analysis technique (cross bi-spectral analysis) is applied to identify the surge and sway quadratic transfer functions (QTFs) of the slowly varying excitation, together with the linearized low-frequency damping. The paper also presents a semi-empirical formula developed in the scope of the EXWAVE JIP to correct potential flow mean wave drift force coefficients of Semis in high seastates with current. The empirical QTFs are then compared with numerical predictions. Comparisons with potential flow coefficients lead to conclusions on the role of viscous drift. The semi-empirical formula is assessed based on comparisons with test results and concluded that it provides a significant improvement compared to potential flow predictions.

Traditional detection of aquatic invasive species, via morphological identification is often time-consuming and can require a high level of taxonomic expertise, leading to delayed mitigation responses. Environmental DNA (eDNA) detection approaches of multiple species using Illumina-based sequencing technology have been used to overcome these hindrances, but sample processing is often lengthy. More recently, portable nanopore sequencing technology has become available, which has the potential to make molecular detection of invasive species more widely accessible and to substantially decrease sample turnaround times. However, nanopore-sequenced reads have a much higher error rate than those produced by Illumina platforms, which has so far hindered the adoption of this technology. We provide a detailed laboratory protocol and bioinformatic tools to increase the reliability of nanopore sequencing to detect invasive species, and we test its application using invasive bivalves. We sampled water from sites with pre-existing bivalve occurrence and abundance data, and contrasting bivalve communities, in Italy and Portugal. We extracted, amplified and sequenced eDNA with a turnaround of 3.5 days. The majority of processed reads were ≥ 99 % identical to reference sequences. There were no taxa detected other than those known to occur. The lack of detections of some species at some sites could be explained by their known low abundances. This is the first reported use of MinION to detect aquatic invasive species from eDNA samples. The approach can be easily adapted for other metabarcoding applications, such as biodiversity assessment, ecosystem health assessment and diet studies.

International audience; This cross-sectional study evaluates the association of major adverse cardiac events (MACE) integrated with fractional flow reserve as the management strategy for diabetes with outcomes in patients with ambiguous lesions who undergo angiography.Key PointsQuestionWhat are the usefulness, rate of major adverse cardiovascular events (MACE), and clinical outcomes of routinely integrating fractional flow reserve in the management strategy for patients with diabetes who undergo coronary angiography? FindingsIn this cross-sectional study of 1983 patients, overall reclassification by fractional flow rate was high and similar in patients with diabetes (41.2%) and patients without diabetes (37.5%); however, reclassification from medical treatment to revascularization was more frequent among patients with diabetes. The rate of 1-year MACE was similar in reclassified (9.7%) and nonreclassified (12.0%) patients with diabetes, and the rate of MACE of patients deferred based on fractional flow reserve was similar among those with and without diabetes. MeaningThe findings suggest that management strategies guided by fractional flow reserve, including revascularization deferral, may be useful for patients with diabetes.ImportanceApproximately one-third of patients considered for coronary revascularization have diabetes, which is a major determinant of clinical outcomes, often influencing the choice of the revascularization strategy. The usefulness of fractional flow reserve (FFR) to guide treatment in this population is understudied and has been questioned. ObjectiveTo evaluate the usefulness and rate of major adverse cardiovascular events (MACE) of integrating FFR in management decisions for patients with diabetes who undergo coronary angiography. Design, Setting, and ParticipantsThis cross-sectional study used data from the PRIME-FFR study derived from the merger of the POST-IT study (Portuguese Study on the Evaluation of FFR-Guided Treatment of Coronary Disease [March 2012-November 2013]) and R3F study (French Study of FFR Integrated Multicenter Registries Implementation of FFR in Routine Practice [October 2008-June 2010]), 2 prospective multicenter registries that shared a common design. A population of all-comers for whom angiography disclosed ambiguous lesions was analyzed for rates, patterns, and outcomes associated with management reclassification, including revascularization deferral, in patients with vs without diabetes. Data analysis was performed from June to August 2018. Main Outcomes and MeasuresDeath from any cause, myocardial infarction, or unplanned revascularization (MACE) at 1 year. ResultsAmong 1983 patients (1503 [77%] male; mean [SD] age, 65 [10] years), 701 had diabetes, and FFR was performed for 1.4 lesions per patient (58.2% of lesions in the left anterior descending artery; mean [SD] stenosis, 56% [11%]; mean [SD] FFR, 0.81 [0.01]). Reclassification by FFR was high and similar in patients with and without diabetes (41.2% vs 37.5%, P=.13), but reclassification from medical treatment to revascularization was more frequent in the former (142 of 342 [41.5%] vs 230 of 730 [31.5%], P=.001). There was no statistical difference between the 1-year rates of MACE in reclassified (9.7%) and nonreclassified patients (12.0%) (P=.37). Among patients with diabetes, FFR-based deferral identified patients with a lower risk of MACE at 12 months (25 of 296 [8.4%]) compared with those undergoing revascularization (47 of 257 [13.1%]) (P=.04), and the rate was of the same magnitude of the observed rate among deferred patients without diabetes (7.9%, P=.87). Status of insulin treatment had no association with outcomes. Patients (6.6% of the population) in whom FFR was disregarded had the highest MACE rates regardless of diabetes status. Conclusions and RelevanceRoutine integration of FFR for the management of coronary artery disease in patients with diabetes may be associated with a high rate of treatment reclassification. Management strategies guided by FFR, including revascularization deferral, may be useful for patients with diabetes.

Acute Kidney Injury (AKI) is a very frequent complication in the Acute Liver Failure (ALF) population associated with negative outcomes. We aim to evaluate the impact of AKI duration on the outcomes of an ALF population. A 20-year retrospective analysis of ALF patients admitted to an Intensive Care Unit (ICU) was performed. Chronic liver failure, chronic kidney disease on renal replacement therapy, dialysis requirement within the week prior or an ICU stay of less than 48 h after AKI diagnosis, were exclusion criteria. AKI was defined according to the KDIGO criteria and classified into transient (

An innovative floating hydrocarbon storage facility (FHSF) has been proposed to utilize the shielded near-shore area for countries with large demand on the land space such as Singapore and Japan. The concept comprises 14 floating hydrocarbon storage tanks (FHST) and several surrounding floating barges. All the modular designed FHSTs are loosely connected to the barges through a soft mooring system so as to reduce the loads, and the entire system is free to float to reduce the tidal influence. The single FSHT has been proven to have moderate hydrodynamic responses in previous studies, but there still exist concerns on the influence of potential resonances in the narrow gaps and the strong hydrodynamic interactions. The loads on the specially designed soft mooring system have to be checked. The complete system is complex and difficult to analyze. So, experimental studies were performed on both a simplified system and the complete system to ensure the quality and reduce the uncertainty in the experiments. The simplified system consists of two FHSTs and a surrounding floating barge frame. The experiments were performed in the ocean basin in SINTEF Ocean. A series of random, wide-band and realistic random wave tests were carried out to generate benchmark data to verify numerical analysis tools. This paper will focus on this simplified system that represents the complete system’s behavior. A frequency domain numerical model of the simplified system was established based on potential theory. Empirical coefficients were used to account for viscous damping. The numerical results are comparable to the experimental results in general. The statistical responses of the FHST in the design sea states are also within the acceptable range even with the hydrodynamic interactions. However, further improvement on the system such as a better design of the floating barge is necessary.