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Accurate estimates of extreme waves are central for maritime activities, and stochastic wave models are the best option available for practical applications. However, the way currents influence the statistics of space–time extremes in spectral wave models has not been properly assessed. Here we demonstrate impacts of the wave modulation caused by one of the world's strongest open ocean tidal currents, which reaches speeds of at least 3 m s−1. For a bimodal swell and wind sea state, we find that most intense interactions occur when the wind sea opposes the tidal current, with an increase in significant wave height and spectral steepness up to 45% and 167%, respectively. The steepness modulation strengthens the second-order Stokes contribution for the normalized extreme crests, which increases between 5% and 14% during opposing wind sea and current. The normalized extreme wave heights have a strong dependence on the narrow-bandedness parameter, which is sensitive to the variance distribution in the bimodal spectrum, and we find an increase up to 12% with currents opposing the wind sea. In another case of swell opposing a tidal jet, we find the spectral steepness to exceed the increase predicted by a simplified modulation model. We find support in single-point observations that using tidal currents as forcing in wave models improves the representation of the expected maximum waves, but that action must be taken to close the gap of measurements in strong currents. Significance Statement: The purpose of this study is to investigate how a very strong tidal current affects the surface wave field, and how it changes the stochastic extreme waves formulated for a space–time domain. Our results suggest that the expected maximum waves become more realistic when tidal currents are added as forcing in wave models. Here, the expected extremes exceed traditional model estimates, i.e., without current forcing, by more than 10%. These differences have implications for maritime operations, both in terms of planning of marine structures and for navigational purposes. However, there is a significant lack of observations in environments with such strong currents, which are needed to further verify our results. [ABSTRACT FROM AUTHOR]

In this paper the Self-Organizing Map (SOM) technique to assess the multivariate sea wave climate at a site is analyzed and discussed with the aim of a more complete representation which includes the most severe sea states that otherwise would be missed by the standard SOM. Indeed, it is commonly recognized, and herein confirmed, that SOM is a good regressor of a sample where the density of events is high (e.g. for low/moderate and frequent sea states), while SOM fails where the density is low (e.g. for severe and rare sea states). Therefore, we have considered a trivariate wave climate (composed by significant wave height, mean wave period, and mean wave direction) collected continuously at the Acqua Alta oceanographic tower (northern Adriatic Sea, Italy) during the period 1979-2008. Three different strategies derived by the standard SOM have been tested in order to widen the range of applicability to extreme events. The first strategy contemplates a pre-processing of the input dataset with the Maximum Dissimilarity Algorithm; the second and the third strategies focus on the post-processing of SOM outputs, resulting in a two-steps SOM, where the first step is the standard SOM applied to the original dataset, and the second step is an additional SOM on the events exceeding a threshold (either taking all the events over the threshold or only the peaks of storms). Results suggest that post-processing strategies are more effective than the pre-processing one in representing the extreme wave climate, both in the time series and probability density spaces. In addition, a complete graphical representation of the outcomes of two-steps SOM as double-sided maps is proposed. [ABSTRACT FROM AUTHOR]

During the oceanographic campaign CARPET2014, between 30 January and 4 February 2014, a total of 478 microstructure profiles (grouped into 145 ensembles) and 38 CTD casts were made in the Gulf of Trieste (Northern Adriatic Sea) under moderate wind forcing (average wind speed 10ms-1) and heat fluxes (net negative heat flux in the range of 150 to 400Wm-2). Among the collected profiles, there were three sets of yoyo casts, each lasting for about 12 h for a total of 50 casts. Overall, these represent the first turbulence observations collected in the Gulf of Trieste. Microstructure profiles collected with a free-falling profiler must be taken in enables of repeated casts, with the objective of obtaining more statistically significant values for turbulence parameters. This approach is certainly feasible in shallow waters, but has a down side when the vertical density structure includes strong interfaces that can move up or down between subsequent casts, under the influence of tides and internal waves. In order to minimize the smearing effect of such interfacial displacements on mean quantities, we developed an algorithm to realign, according to the temperature profile, successive microstructure profiles to produce sharper and more meaningful mean profiles of measured turbulence parameters. During CARPET2014, the water column in the Gulf evolved from a well-mixed condition to a stratified one, due to Adriatic waters intruding at the bottom along the Gulf's south-eastern coast. These waters stratified the water column and changed its stability characteristics, which in turn prevented wind driven turbulence from penetrating to the bottom of the water column. In this study, we show that during a warm and relatively dry winter, such as in 2014, the Gulf of Trieste was not completely mixed because of the influence of bottom waters intruding from the open sea, even under moderate wind forcing. Inside the Gulf, two types of water intrusions from the Adriatic Sea were observed during the yoyo casts: one coming from its northern coast (i.e. warmer, saltier and more turbid) and one coming from the open sea in front of the Po Delta (i.e. cooler, fresher and less turbid). Those two intrusions behaved similarly but had a different impact on turbulence kinetic energy dissipation rate profiles. The former, with high turbidity, acted as a barrier to wind-driven turbulence, while the latter, with low sediment concentrations and a smaller density gradient when compared to the rest of the water column, was not able to suppress downward penetration of turbulence from the surface to the same degree. [ABSTRACT FROM AUTHOR]

• Predictability of the explosive cyclogenesis and its consequences. • Orography was instrumental in shaping the local wind and wave conditions. • Coasts were hit by two heavy, but different, wave systems within a few hours. • The local conditions were extremely sensitive to minor changes of the minimum position. We analyse the storm that hit the Ligurian Sea in the afternoon of 29 October 2018. Although not a historical extreme, the event was unique in itself for the superposition of an explosive cyclogenesis on a preexisting southerly flow. Combined with the general meteorological pattern, this led in the range of a few hours to quite different, similarly severe wind and wave conditions. The storm has been analysed using both the models of the European Centre for Medium-Range Weather Forecasts and a nested WRF + WW3 one. The orography of Corsica has been instrumental in shaping the local fields. The storm, and in particular the cyclogenesis, were well forecast. However, as evidenced especially by the different ensemble members, minor differences in the position of the minimum could lead to substantial differences at specific locations, also where major damages were reported. [ABSTRACT FROM AUTHOR]

• Spatio-temporal maximum wave heights occur to the north-east of the cyclone's eye, where sea states are more energetic. • Individual waves with normalized extreme heights are met to the south/south-west of the moving cyclone. • Directional spread and bound nonlinear interactions play a significant role in producing extreme waves. • Different physical mechanisms can trigger high waves in the sea regions under cyclone winds. Principles of the spatio-temporal statistics are used to investigate the characteristics of short-term/range extreme sea waves and related sea-state parameters under cyclone winds (northern hemisphere). We base our analysis upon consistent stereo-imaging observations of the 3D (2D space + time) sea surface elevation field, and spectral wave model results in the Northwestern Pacific during tropical storm Kong-rey (2018). The focus is on the extreme value analysis of individual maximum sea surface elevations (crest heights) and maximum crest-to-trough wave heights. Results highlight the sea areas around the storm centre where the spatio-temporal highest waves are more likely, and, via scale analysis, the principal mechanisms responsible for the occurrence of extreme conditions in bimodal (composed of wind-sea and swell) and short-crested storm seas. We find that individual waves are the highest to the north-east of the translating cyclone, where sea states are more energetic. However, in the south/south-west of the centre, where opposing wind-sea/swell sea states dominate, directional spread and bound nonlinear interactions are enhanced. In this area, more extreme waves may occur, having the maximum crest and wave heights mean values in excess of 1.3 and 2.1 times the significant wave height, respectively. This set of results provides insights into the role of the dispersive and directional focusing enhanced by nonlinearities up to the second order as an effective mechanism for the formation of extreme waves under cyclone winds. To examine what physical mechanism is behind the generation of extreme waves in different regions around the cyclone, we also explore for comparison areas where nonlinear four-wave interactions are more likely to occur. [ABSTRACT FROM AUTHOR]

Reliable predictions of oceanic waves during storms have always been foremost for offshore design and operation, coastal hazards, and navigation safety. Indeed, many accidents that occurred during storms were ascribed to the impact with unforeseen large waves. In this context, the purpose of this study is to improve the present state extreme wave estimate from spectral wave models. We describe an implementation for the WAM model, and we investigate the use of WAM and WAVEWATCH III fed with common routines designed to evaluate the short-term/range maximum wave statistics. An extensive assessment of models' results in the Adriatic and North Sea is performed using time and space-time wave measurements, and through an intercomparison between WAM and WAVEWATCH III applied with three different input/dissipation source term parametrizations (ST3/4/6). Further, models' capabilities are investigated, and extreme waves characterized, in the Mediterranean Sea, aiming also at disentangling the wave spectrum bulk parameters that may point to favorable conditions for the generation of high waves. Based on the comparisons between model results and measurements, we conclude that for the model characterization of extremes, the accuracy of the significant wave height is pivotal; differences between models of other spectral parameters seem to have a minor effect. • We improve the present state extreme wave estimate from spectral wave models WAM and WAVEWATCH III®. • We aim at disentangling the wave spectrum bulk parameters that may point to favorable conditions for the generation of high waves. • Model capabilities are examined, and extreme waves characterized, in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Background: Among the unknowns posed by the coronavirus disease 2019 (COVID-19) outbreak, the role of biological sex to explain disease susceptibility and progression is still a matter of debate, with limited sex-disaggregated data available. Methods: A retrospective analysis was performed to assess if sex differences exist in the clinical manifestations and transitions of care among hospitalized individuals dying with laboratory-confirmed SARS-CoV-2 infection in Italy (February 27–June 11, 2020). Clinical characteristics and the times from symptoms' onset to admission, nasopharyngeal swab, and death were compared between sexes. Adjusted multivariate analysis was performed to identify the clinical features associated with male sex. Results: Of the 32,938 COVID-19-related deaths that occurred in Italy, 3517 hospitalized and deceased individuals with COVID-19 (mean 78 ± 12 years, 33% women) were analyzed. At admission, men had a higher prevalence of ischemic heart disease (adj-OR = 1.76, 95% CI 1.39–2.23), chronic obstructive pulmonary disease (adj-OR = 1.7, 95% CI 1.29–2.27), and chronic kidney disease (adj-OR = 1.48, 95% CI 1.13–1.96), while women were older and more likely to have dementia (adj-OR = 0.73, 95% CI 0.55–0.95) and autoimmune diseases (adj-OR = 0.40, 95% CI 0.25–0.63), yet both sexes had a high level of multimorbidity. The times from symptoms' onset to admission and nasopharyngeal swab were slightly longer in men despite a typical acute respiratory illness with more frequent fever at the onset. Men received more often experimental therapy (adj-OR = 2.89, 95% CI 1.45–5.74) and experienced more likely acute kidney injury (adj-OR = 1.47, 95% CI 1.13–1.90). Conclusions: Men and women dying with COVID-19 had different clinical manifestations and transitions of care. Identifying sex-specific features in individuals with COVID-19 and fatal outcome might inform preventive strategies. [ABSTRACT FROM AUTHOR]

The article discusses a comparison between the pulmonary artery catheter (PAC) and the fourth generation of the FloTrac system (FloTrac/EV1000) in estimating cardiac output (CO) during robotic-assisted off-pump coronary artery bypass (OPCAB) surgery. The authors found that the FloTrac/EV1000 system had a bias of 1.46 L/min and a high percentage error of 72.98%, indicating that its reliability in estimating CO was not acceptable, especially in patients with low systemic vascular resistances (SVRI). However, the authors of the article also mention their own study from over 10 years ago, which evaluated the accuracy and precision of the second generation of FloTrac and found better results. They suggest that the conflicting results between studies could be due to the inclusion of patients supported with an intra-aortic balloon pump (IABP), which affects the arterial line profile used in pulse contour analysis. They propose that excluding patients with IABP or increasing the sample size could lead to different conclusions. Additionally, they note that the PAC catheter, considered the clinical gold standard, also has a percentage error greater than 40% when compared to the true gold standard aortic flow probe. The authors conclude that while mini-invasive devices like FloTrac are precise, they need to be more accurate and can be influenced by the type and time of surgery. They also suggest that the accuracy of FloTrac may be better [Extracted from the article]

Given the growing availability of directional spectra of ocean waves, we explore two different statistical approaches to mine large spectra databases: Spectral Partitions Statistics (SPS) and Self-Organizing Maps (SOM). The first method is not new in the literature, while the second one is for the first time here applied to directional wave spectra. The main goal is to improve the characterization of the directional wave climate at a site, providing a more complete and consistent description than that obtained from traditional statistical methods based on integral spectral parameters (e.g., H s , T m , θ m). Indeed, while the use of integral parameters allows a direct application of standard techniques for statistical analysis, important information related to the physics of the processes may be overlooked (e.g., the presence of multiple wave systems, for instance locally and remotely generated). The two proposed methods do not exclude integral parameters analysis, but they further allow accounting for different events (e.g., with different genesis) independently. Although SPS and SOM are equally valid for both numerical model and observational data, we illustrate their potential using a 37-year long (1979–2015) model dataset of directional wave spectra at a study site in the western Mediterranean Sea. We show that standard integral parameters fail to show the complex and even multimodal conditions at this site, that are otherwise revealed by the directional spectra statistical analysis. Although the processing pathways and the resulting indicators of both SPS and SOM are substantially different, we observe that their results are mutually consistent, and provide a better insight into the physical processes at work. [ABSTRACT FROM AUTHOR]

The LATEMAR project aims at improving the modelling of large wave events during marine storms in the framework of the Copernicus Marine Environment Monitoring Service (CMEMS). Indeed, at present, CMEMS operational systems only release average and peak wave parameters, with no information on individual waves whatsoever. However, developments of the state-of-the-art third-generation wave models (WAVEWATCH III and SWAN, for instance) demonstrated that, using the directional wave spectrum and theoretical statistical models for wave extremes, forecasters can accurately infer the expected shape and likelihood of the maximum waves during marine storms. The main goal of the LATEMAR project is therefore to provide the wave models used by the CMEMS service (WAM and WAVEWATCH III) with the procedures to explicitly estimate the maximum wave heights for each sea state. Besides this, further goals of LATEMAR are the following: perform an extensive assessment of the modeled maximum wave events using observations collected from an oceanographic station; inter-compare WAM and WAVEWATCH III model performance in a test area (Mediterranean Sea); investigate the sensitivity on sea state parameters of the maximum waves. All model developments and evaluations resulting from this R&D project will be directly applicable to the wave model forecasting systems, extending thus the CMEMS product catalogue. [ABSTRACT FROM AUTHOR]

In this study, we use reanalysis datasets to characterize the maximum crest, crest-to-trough and envelope heights of sea states, on a global and long-term scale. In particular, we rely on the ERA-Interim directional wave spectra, which are used to estimate the parameters of the probability distributions of wave maxima. To represent the typical single-point observations we use time extreme theoretical models, while to take the three-dimensional geometry and short-crestedness of ocean waves into account, we adopt a space-time extreme model. In order to assess the confidence limits of the reanalysis-based wave maxima we verify them against buoy and stereo-video wave observations collected in the North Pacific Ocean. We provide the global assessment of maximum crest, crest-to-trough and envelope heights during typical and extreme conditions, showing where the largest values are attained, that is in the mid-latitude storm belts, in particular in the North Atlantic Ocean. With respect to previous wave climate studies that focused on the significant wave height only, in this study, besides quantifying the maximum wave heights in magnitude, we also highlight the role of wave parameters such as wave steepness and kurtosis (measures of nonlinearity) and spectral bandwidth (measure of irregularity). Finally, we stress the relevant contribution of the short-crestedness, which should be taken into account in assessing wave maxima for the safety of navigation, ship routing and marine structural design. [ABSTRACT FROM AUTHOR]

Background: The role of nutrition in donor after brain deaths (DBDs) has yet to be adequately discussed. The primary aim of this study was to investigate whether the nutritional intake in the 48 h before organ retrieval may play a role on the graft functional recovery assessed with Model for Early Allograft Function (MEAF) Score. Methods: Single‐center retrospective study evaluating all liver transplants performed at the University Hospital of Udine from January 2010 to August 2020. Patients receiving grafts from DBD donors fed with artificial enteral nutrition in the 48 h prior to organ procurement (EN‐group) or who did not (No‐EN‐group). Caloric debt was calculated using the difference between the calculated caloric needs and the effective calories delivered through enteral nutrition. Results: Livers from EN‐group presented a lower mean MEAF score compared to the no‐EN‐group: 3.39 ± 1.46 versus 4.15 ± 1.51, respectively (p =.04). A positive correlation between caloric debt and the MEAF score was found within the overall population (r =.227, p =.043) as well as in EN‐group (r =.306, p =.049). Conclusions: Donor's nutritional intake in the final 48 h before organ procurement correlates with MEAF score, and nutrition probably plays a positive role on the functional recovery of the graft. Large future randomized controlled trials are needed to confirm this preliminary results. [ABSTRACT FROM AUTHOR]

Background: Patients hospitalised for COVID-19 may present with or acquire bacterial or fungal infections that can affect the course of the disease. The aim of this study was to describe the microbiological characteristics of laboratory-confirmed infections in hospitalised patients with severe COVID-19. Methods: We reviewed the hospital charts of a sample of patients deceased with COVID-19 from the Italian National COVID-19 Surveillance, who had laboratory-confirmed bacterial or fungal bloodstream infections (BSI) or lower respiratory tract infections (LRTI), evaluating the pathogens responsible for the infections and their antimicrobial susceptibility. Results: Among 157 patients with infections hospitalised from February 2020 to April 2021, 28 (17.8%) had co-infections (≤ 48 h from admission) and 138 (87.9%) had secondary infections (> 48 h). Most infections were bacterial; LRTI were more frequent than BSI. The most common co-infection was pneumococcal LRTI. In secondary infections, Enterococci were the most frequently recovered pathogens in BSI (21.7% of patients), followed by Enterobacterales, mainly K. pneumoniae, while LRTI were mostly associated with Gram-negative bacteria, firstly Enterobacterales (27.4% of patients, K. pneumoniae 15.3%), followed by A. baumannii (19.1%). Fungal infections, both BSI and LRTI, were mostly due to C. albicans. Antibiotic resistance rates were extremely high in Gram-negative bacteria, with almost all A. baumannii isolates resistant to carbapenems (95.5%), and K. pneumoniae and P. aeruginosa showing carbapenem resistance rates of 59.5% and 34.6%, respectively. Conclusions: In hospitalised patients with severe COVID-19, secondary infections are considerably more common than co-infections, and are mostly due to Gram-negative bacterial pathogens showing a very high rate of antibiotic resistance. [ABSTRACT FROM AUTHOR]

On October 29, 2018 a very severe storm affected Northern Italy, including the Adriatic Sea. The ensuing surge and wave conditions at and in front of Venice stand at the extreme tail of the respective historical return period distributions. The large set of available measured data, at the coast and at the offshore oceanographic tower, coupled with detailed numerical simulations, allows a keen analysis of the storm, its predictability and in particular of the ensuing enhanced coastal processes. These include the coastal set-up, the input information for tidal prediction in Venice, the documented passage of an atmospheric cold front and, using the local tidal data, the derived possibility of estimating the surface wind stress, the evidence of reflected waves from the coast and the associated seismometers signal 40 km inland. The highest crest and wave heights measured at the tower are beyond what is suggested by non-linear statistics. The relative out-of-scale magnitude of the three major storms since 1966 suggests the possibility that they belong to a self-standing family of events. [ABSTRACT FROM AUTHOR]

This study aims at characterizing the distinctive features of a spatio-temporal nonlinear wave surface. We analyze wind-generated 3-D wave fields observed during the passage of an atmospheric front, which led to a wide directional spreading of wave energy. Data were acquired from the ocean research station Socheongcho-ORS (Yellow Sea) with a stereo wave imaging system. They include 3-D (i.e. 2-D + time) measurements of the sea surface elevation with high spatial and temporal resolution over a swath larger than any previous similar deployment. We examine the shape and the nonlinear properties of the wavenumber/frequency 3-D wave spectrum, and the characteristic spatial, temporal and spatio-temporal length scales of the wave field. We then focus on analyzing the probability of occurrence and the spatio-temporal size of the rogue waves we identified in the data. In particular, we provide for the first time an empirical estimate of the extent of the horizontal sea surface spanned by rogue waves. We also propose and assess a novel strategy to determine from the 3-D wave spectrum the vertical current profile, to be then used to map the spectrum on intrinsic frequencies. [ABSTRACT FROM AUTHOR]

As the size of vessels progressively increases to compete in the global trade, the impact evaluation of navigation in waterways and shallow coastal ecosystems become more important. Therefore, suitable tools to investigate processes are required to support a sustainable management of ship traffic. This work tests a new methodology, based on a numerical model chain, that reproduces the hydrodynamic field close to the ship hull and the ship-induced wave propagation in the surrounding shallow areas. The model chain includes an unstructured hydrodynamic model forced by the near-field estimation of a computational fluid dynamics simulation. The modeling system has been applied to a major navigation channel and surrounding tidal flats in the Venice Lagoon (Italy). Field observations and a theoretical framework were used to characterize the ship waves and to validate the modeling system. Results show that the deeper the initial depression, the larger the dissipation over the tidal flat. In these conditions smaller vessels sailing at higher speed produce smaller waves with low amplitudes compared to larger ships traveling at lower speed. We considered vessels moving at different speeds providing useful information to evaluate impacts and to define criteria for decision support systems for a sustainable management of navigation. [ABSTRACT FROM AUTHOR]

The use of spatial and spatio-temporal data is rapidly changing the paradigm of wind wave observations, which have been traditionally restricted to time series from single-point measurements (e.g. from buoys, wave gauges). Active and passive 2D remote sensors mounted on platforms, ships, airplanes and satellites are now becoming standards in the oceanographic community and industry. Given the covered area ranging from centimeters to kilometers, such sensors are now a valuable tool for ocean and coastal observations. In this paper, we intercompare spatio-temporal wind wave data acquired with two state-of-the-art techniques, namely the stereo wave imaging and the X-band marine radar. The comparison was performed by operating the two instruments on an oceanographic research platform during a crossing-sea condition. We analyzed the statistical properties of the wave field, and its directional and omni-directional energy distributions. From our analysis, we suggest that stereo data can be exploited to find the best radar Modulation Transfer Function and scale factor needed to estimate wave parameters. Moreover, the fusion of the two systems will allow to broaden the scales covered by any one measurement, and to retrieve reliable directional wave spectra from short (∼1 m) to mid-wavelengths (∼100 m). [ABSTRACT FROM AUTHOR]

Stereo 3D reconstruction of ocean waves is gaining more and more popularity in the oceanographic community and industry. Indeed, recent advances of both computer vision algorithms and computer processing power now allow the study of the spatio-temporal wave field with unprecedented accuracy, especially at small scales. Even if simple in theory, multiple details are difficult to be mastered for a practitioner, so that the implementation of a sea-waves 3D reconstruction pipeline is in general considered a complex task. For instance, camera calibration, reliable stereo feature matching and mean sea-plane estimation are all factors for which a well designed implementation can make the difference to obtain valuable results. For this reason, we believe that the open availability of a well tested software package that automates the reconstruction process from stereo images to a 3D point cloud would be a valuable addition for future researches in this area. We present WASS ( http://www.dais.unive.it/wass ), an Open-Source stereo processing pipeline for sea waves 3D reconstruction. Our tool completely automates all the steps required to estimate dense point clouds from stereo images. Namely, it computes the extrinsic parameters of the stereo rig so that no delicate calibration has to be performed on the field. It implements a fast 3D dense stereo reconstruction procedure based on the consolidated OpenCV library and, lastly, it includes set of filtering techniques both on the disparity map and the produced point cloud to remove the vast majority of erroneous points that can naturally arise while analyzing the optically complex nature of the water surface. In this paper, we describe the architecture of WASS and the internal algorithms involved. The pipeline workflow is shown step-by-step and demonstrated on real datasets acquired at sea. [ABSTRACT FROM AUTHOR]

Stereo 3D reconstruction is continuously increasing its popularity in the study of mid-to small-scale sea waves. In the recent past, different approaches have been proposed to reconstruct the space-time sea surface elevation field from synchronized stereo frames. Usually, the reconstruction is performed by first recovering a dense and sparse 3D point cloud from stereo pairs and then by interpolating it into a regular grid. Even considering state-of-the-art methods, with typical image resolutions, it's unlikely to perform the first step in less than dozens of seconds (without paralellization), that can easily doubled if we include the subsequent interpolation step. This will limit the applicability of stereo based wave analysis for all the approaches (like monitoring or data assimilation) in which the time between the raw acquisition and the output of processed data is critical. In this paper, we propose a new method to directly estimate the sea surface spectrum over time from a sequence of stereo frames. We exploit the frequency dispersion relation of gravity waves and the (Non-uniform) Fast Fourier Transform to continuously update the 3D surface and 2D wavenumber spectrum estimations given a sparse set of matching features between the two frames. This effectively combines the two aforementioned steps with a performance gain of more than an order of magnitude while keeping a reconstruction accuracy that is extremely close to the current state-of-the-art approaches. Code is available at https://gitlab.com/fibe/wassfast. • WASSfast is a sea-waves 3D reconstruction method optimized for speed. • Wave spectrum is continuously estimated from a sparse set of stereo matches. • Extensive tests with real-data show good accuracy and 10× faster processing. [ABSTRACT FROM AUTHOR]

Background: Postoperative pulmonary complications (PPCs) remain a challenge after esophagectomy. Despite improvement in surgical and anesthesiological management, PPCs are reported in as many as 40% of patients. The main aim of this study is to investigate whether early application of high-flow nasal cannula (HFNC) after extubation will provide benefit in terms of reduced PPC frequency compared to standard oxygen therapy., Methods: Patients aged 18-85 years undergoing esophagectomy for cancer treatment with radical intent, excluding those with American Society of Anesthesiologists (ASA) score >3 and severe systemic comorbidity (cardiac, pulmonary, renal or hepatic disease) will be randomized at the end of surgery to receive HFNC or standard oxygen therapy (Venturi mask or nasal goggles) after early extubation (within 12 hours after the end of surgery) for 48 hours. The main postoperative goals are to obtain SpO 2 ≥94% and adequate pain control. Oxygen therapy after 48 hours will be stopped unless the physician deems it necessary. In case of respiratory clinical worsening, patients will be supported with the most appropriate tool (noninvasive ventilation or invasive mechanical ventilation). Pulmonary [pneumonia, pleural effusion, pneumothorax, atelectasis, acute respiratory distress syndrome (ARDS), tracheo-bronchial injury, air leak, reintubation, and/or respiratory failure] complications will be recorded as main outcome. Secondary outcomes, including cardiovascular, surgical, renal and infective complications will also be recorded. The primary analysis will be carried out on 320 patients (160 per group) and performed on an intention-to-treat (ITT) basis, including all participants randomized into the treatment groups, regardless of protocol adherence. The primary outcome, the PPC rate, will be compared between the two treatment groups using a chi-square test for categorical data, or Fisher's exact test will be used if the assumptions for the chi-square test are not met., Discussion: Recent evidence demonstrated that early application of HFNC improved the respiratory rate oxygenation index (ROX index) after esophagectomy but did not reduce PPCs. This randomized controlled multicenter trial aims to assess the potential effect of the application of HFNC versus standard oxygen over PPCs in patients undergoing esophagectomy., Trial Registration: This study is registered at clinicaltrial.gov NCT05718284, dated 30 January 2023., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-24-575/coif). The authors have no conflicts of interest to declare., (2024 Journal of Thoracic Disease. All rights reserved.)

We read with great interest the study by Chahyun Oh et al., which compared estimates of cardiac output (CO) provided by the FloTrac system (CO-FloTrac) with those obtained with continuous thermodilution (COcont) after time adjustments using continuous recordings of intraoperative physiological datal [...].

Climbing plants require an external support to grow vertically and enhance light acquisition. Climbers that find a suitable support demonstrate greater performance and fitness than those that remain prostrate. Support search is characterized by oscillatory movements (i.e., circumnutation), in which plants rotate around a central axis during their growth. Numerous studies have elucidated the mechanistic details of circumnutation, but how this phenomenon is controlled during support searching remains unclear. To fill this gap, here we tested whether simulation-based machine learning methods can capture differences in movement patterns nested in actual kinematical data. We compared machine learning classifiers with the aim of generating models that learn to discriminate between circumnutation patterns related to the presence/absence of a support in the environment. Results indicate that there is a difference in the pattern of circumnutation, depending on the presence of a support, that can be learned and classified rather accurately. We also identify distinctive kinematic features at the level of the junction underneath the tendrils that seems to be a superior indicator for discerning the presence/absence of the support by the plant. Overall, machine learning approaches appear to be powerful tools for understanding the movement of plants.

Background: The carotid artery velocity-time integral (CVTI) and the carotid Doppler peak velocity (cDPV), as well as measures of their variation induced by the respiratory cycle, have been proposed as fast and easy to obtain ultrasound measures for assessing fluid responsiveness in intensive care unit patients. To investigate this possibility, we conducted a prospective observational study in hemodynamically unstable patients under mechanical ventilation., Methods: From May 1 to December 31, 2019, we conducted a prospective observational study involving 50 hemodynamically unstable patients under mechanical ventilation. We obtained a total of 800 Doppler ultrasound measurements from the left common carotid artery and at the level of the aortic annulus in the apical five-chamber view. The two measurements were performed before and after a 7 mL/kg fluid challenge and within the first hour of the onset of hemodynamic instability. The maximum Doppler peak velocity, the minimum Doppler peak velocity, and the maximum and minimum VTI at both the aortic and carotid level were acquired., Results: Twenty-eight (56%) patients showed a ≥15% increase in AoVTI after the fluid challenge, and were therefore identified as "fluid responders". All Doppler measurements were always significantly greater (P<0.0001) in fluid responders in relation to both carotid and aortic parameters. Good agreement between the above-mentioned measurements was found: Cohen's kappa coefficient between the carotid and aortic ΔDPV was 0.76 (95% CI 0.58-0.94); and between the Carotid and Aortic ΔVTI it was 0.84 (95% CI 0.68-0.99)., Conclusions: CDPV was found to predict fluid responsiveness in unstable mechanically ventilated patients.

Of the various muscles that make up the respiratory system, the diaphragm is the prima donna. In the past, only specialist research centers were able to estimate and challenge the effort of this muscle; this was achieved by measuring transdiaphragmatic pressure-an invasive technique involving a double-balloon probe inserted through the esophagus-or by measuring twitch pressure (ie, the pressure generated at the outside tip of the endotracheal tube). However, the prevalence of diaphragm dysfunction in critically ill patients requiring intubation can exceed 60% (at the time of hospital admission) and may rise to as high as 80% in patients requiring prolonged mechanical ventilation and experiencing difficult weaning. Although still in its infancy, modern ultrasound (US) provides a fascinating way to study the diaphragm, permitting the assessment of its excursion, thickness, and thickening. Furthermore, US enables the course of diaphragmatic function to be followed on a day-to-day basis, from intensive care admission to discharge, and it can help us understand the different causes of underlying disease: trauma, infection (eg, sepsis-induced diaphragm dysfunction), cancer, weaning problems (eg, ventilation-induced diaphragm dysfunction), etc. Today, the assessment of diaphragm dysfunction with US provides an important first step toward improving the detection of diaphragm dysfunction and as a protective and supportive strategy for its management. The purposes of this review are as follows: (1) to explore which US method is best for evaluating diaphragm function in the intensive care unit and how and when it should be used, and (2) to discuss which diseases may involve the diaphragm, and what therapies should be used., (Copyright © 2019 Elsevier Inc. All rights reserved.)

During liver transplantation surgery, the pulmonary artery catheter-despite its invasiveness-remains the gold standard for measuring cardiac output. However, the new EV1000 transpulmonary thermodilution calibration technique was recently introduced into the market by Edwards LifeSciences. We designed a single-center prospective observational study to determine if these two techniques for measuring cardiac output are interchangeable in this group of patients. Patients were monitored with both pulmonary artery catheter and the EV1000 system. Simultaneous intermittent cardiac output measurements were collected at predefined steps: after induction of anesthesia (T1), during the anhepatic phase (T2), after liver reperfusion (T3), and at the end of the surgery (T4). The 4-quadrant and polar plot techniques were used to assess trending ability between the two methods. We enrolled 49 patients who underwent orthotopic liver transplantation surgery. We analyzed a total of 588 paired measurements. The mean bias between pulmonary artery catheter and the EV1000 system was 0.35 L/min with 95% limits of agreement of - 2.30 to 3.01 L/min, and an overall percentage error of 35%. The concordance rate between the two techniques in 4-quadrant plot analysis was 65% overall. The concordance rate of the polar plot showed an overall value of 83% for all pairs. In the present study, in liver transplantation patients we found that intermittent cardiac output monitoring with EV1000 system showed a percentage error compared with pulmonary artery catheter in the acceptable threshold of 45%. On the others hand, our results showed a questionable trending ability between the two techniques.