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Inspired from the existing literature on fractal grids in channels and as an extension to classical oscillating grid experiments with simple Cartesian grids, an original investigation of fractal oscillating grid turbulence is here reported. The flows generated by a simple Cartesian grid, a fractal Cartesian grid, a fractal square grid, and a fractal I-shaped grid are studied using particle image velocimetry. Three oscillation frequencies (0.5, 1, and 1.5 Hz) and three stroke amplitudes (0.02, 0.035, and 0.05 m) are considered. The flows are broken down into mean (time averaged), oscillatory (phase dependent), and turbulent contributions using the triple Reynolds decomposition. The oscillation frequency is found to linearly impact the intensity of the mean and the oscillatory flows and the root mean square values of the turbulent fluctuations. In turn, an increase in the stroke amplitude tends to change the topology of the mean and the oscillatory flows. The turbulence intensity is increased by the fractal nature of the grids and is impacted by the mean flow topology, especially for the fractal I-shaped grid for which turbulence is transported away from the grid wake region. The study of the turbulence length scales and spectra reveals that the scales of turbulence mainly depend on the stroke amplitude and the grid geometry. We thus show how fractal oscillating grids can be used to generate turbulence with tailored properties for fundamental studies and practical applications. [ABSTRACT FROM AUTHOR]

Heavy metal pollution in water is a critical environmental concern, demanding effective remediation techniques. Traditional methods, including ion exchange and adsorption, often rely on inductively coupled plasma (ICP) atomic emission spectroscopy/mass spectrometry (AES/MS) for the indirect and time-consuming measurement of residual metal concentrations. In contrast, this study employs innovative direct monitoring of nickel removal by benchtop NMR relaxometry using the paramagnetic properties of Ni2+. To prove the feasibility of the NMR follow-up of Ni2+ uptake, batch experiments were performed with Amberlite IR120, Amberlite IRC748, Dowex Marathon MSC, and activated carbon (AC), which were previously characterized by various techniques. The effect of contact time, pH, and Ni2+ concentration on removal efficiency were studied. Pseudo-first and pseudo-second order kinetic models were used. The Langmuir model effectively described the equilibrium isotherms. The longitudinal and transverse relaxation curves of the loaded resins were biexponential. For sulfonic resins, a strong correlation was observed between the relaxation rates of the fast-relaxing fraction and the Ni2+ content determined by ICP-AES/MS. For IRC748, the effect of Ni2+ loading on the relaxation rates was weaker because of Ni2+ complexation. The relaxation curves of loaded AC revealed multiple fractions. Centrifugation was employed to eliminate the contribution of intergranular water. The remaining intragranular water contribution was biexponential. For high Ni2+ loadings, the relaxation rates of the slow relaxing fraction increased with the AC Ni2+ content. These results mark the initial stage in developing a column experiment to monitor, in real-time, adsorbent loading by NMR relaxometry. [ABSTRACT FROM AUTHOR]

Abstract Background Native valves infective endocarditis due to Escherichia coli is still a rare disease and a particular virulence of some E.coli isolate may be suspected. Case presentation A 79-year-old woman presented during the post-operative period of an orthopedic surgery a urinary tract infection following obstructive ureteral lithiasis. E. coli was isolated from a pure culture of urine and blood sampled simultaneously. After evidence of sustained E.coli septicemia, further investigations revealed acute cholecystitis with the same micro-organism in biliary drainage and a native valve mitral endocarditis. E.coli was identified as O2:K7:H6, phylogenetic group B2, ST141, and presented several putative and proven virulence genes. The present isolate can be classified as both extra-intestinal pathogenic E.coli (ExPECJJ) and uropathogenic E. coli (UPECHM). Conclusions The relationship between the virulent factors present in ExPEC strains and some serotypes of E. coli that could facilitate the adherence to cardiac valves warrants further investigation.

Tropospheric ozone concentrations are sensitive to natural emissions of precursor compounds. In contrast to existing assumptions, recent evidence indicates that terrestrial vegetation emissions in the pre-industrial era were larger than in the present day. We use a chemical transport model and a radiative transfer model to show that revised inventories of pre-industrial fire and biogenic emissions lead to an increase in simulated pre-industrial ozone concentrations, decreasing the estimated pre-industrial to present-day tropospheric ozone radiative forcing by up to 34 % (0.38 to 0.25 W m−2). We find that this change is sensitive to employing biomass burning and biogenic emissions inventories based on matching vegetation patterns, as the co-location of emission sources enhances the effect on ozone formation. Our forcing estimates are at the lower end of existing uncertainty range estimates (0.2–0.6 W m−2), without accounting for other sources of uncertainty. Thus, future work should focus on reassessing the uncertainty range of tropospheric ozone radiative forcing.

The length of time that carbon remains in forest biomass is one of the largest uncertainties in the global carbon cycle, with both recent historical baselines and future responses to environmental change poorly constrained by available observations. In the absence of large-scale observations, models used for global assessments tend to fall back on simplified assumptions of the turnover rates of biomass and soil carbon pools. In this study, the biomass carbon turnover times calculated by an ensemble of contemporary terrestrial biosphere models (TBMs) are analysed to assess their current capability to accurately estimate biomass carbon turnover times in forests and how these times are anticipated to change in the future. Modelled baseline 1985–2014 global average forest biomass turnover times vary from 12.2 to 23.5 years between TBMs. TBM differences in phenological processes, which control allocation to, and turnover rate of, leaves and fine roots, are as important as tree mortality with regard to explaining the variation in total turnover among TBMs. The different governing mechanisms exhibited by each TBM result in a wide range of plausible turnover time projections for the end of the century. Based on these simulations, it is not possible to draw robust conclusions regarding likely future changes in turnover time, and thus biomass change, for different regions. Both spatial and temporal uncertainty in turnover time are strongly linked to model assumptions concerning plant functional type distributions and their controls. Thirteen model-based hypotheses of controls on turnover time are identified, along with recommendations for pragmatic steps to test them using existing and novel observations. Efforts to resolve uncertainty in turnover time, and thus its impacts on the future evolution of biomass carbon stocks across the world's forests, will need to address both mortality and establishment components of forest demography, as well as allocation of carbon to woody versus non-woody biomass growth.

Global fire-vegetation models are widely used to assess impacts of environmental change on fire regimes and the carbon cycle and to infer relationships between climate, land use and fire. However, differences in model structure and parameterizations, in both the vegetation and fire components of these models, could influence overall model performance, and to date there has been limited evaluation of how well different models represent various aspects of fire regimes. The Fire Model Intercomparison Project (FireMIP) is coordinating the evaluation of state-of-the-art global fire models, in order to improve projections of fire characteristics and fire impacts on ecosystems and human societies in the context of global environmental change. Here we perform a systematic evaluation of historical simulations made by nine FireMIP models to quantify their ability to reproduce a range of fire and vegetation benchmarks. The FireMIP models simulate a wide range in global annual total burnt area (39–536 Mha) and global annual fire carbon emission (0.91–4.75 Pg C yr−1) for modern conditions (2002–2012), but most of the range in burnt area is within observational uncertainty (345–468 Mha). Benchmarking scores indicate that seven out of nine FireMIP models are able to represent the spatial pattern in burnt area. The models also reproduce the seasonality in burnt area reasonably well but struggle to simulate fire season length and are largely unable to represent interannual variations in burnt area. However, models that represent cropland fires see improved simulation of fire seasonality in the Northern Hemisphere. The three FireMIP models which explicitly simulate individual fires are able to reproduce the spatial pattern in number of fires, but fire sizes are too small in key regions, and this results in an underestimation of burnt area. The correct representation of spatial and seasonal patterns in vegetation appears to correlate with a better representation of burnt area. The two older fire models included in the FireMIP ensemble (LPJ–GUESS–GlobFIRM, MC2) clearly perform less well globally than other models, but it is difficult to distinguish between the remaining ensemble members; some of these models are better at representing certain aspects of the fire regime; none clearly outperforms all other models across the full range of variables assessed.

Susac syndrome (SS) is a central nervous system vasculitis characterized by the clinical triad of encephalopathy, sensorineural hearing loss, and visual disturbance caused by branch retinal artery occlusion. It is considered as an inflammatory disorder, and an autoimmune etiology is suggested. A 29-year-old man with a history of recent cocaine abuse developed the clinical features of SS. Toxicological analysis including hair testing revealed that cocaine had been adulterated with levamisole. After an initial clinical improvement following corticosteroid therapy, the introduction of mycophenolate mofetil was justified a few weeks later by the progression (or relapse) of the retinal injury, followed by complete recovery. The presence of levamisole has been documented in patients with multifocal inflammatory leukoencephalopathy (MIL). Further investigations are needed to determine if levamisole as an adulterant of cocaine could also play a role in the development of rapidly progressive leukoencephalopathy in young men, with Susac or Susac-like syndromes as possible variants of MIL.

A 60-year-old man was admitted in the intensive care unit (ICU) for a rapidly progressive respiratory failure due to SARS-CoV-2 infection. He developed numerous complications including acute kidney injury (AKI) requiring prolonged continuous renal replacement therapy (CRRT). Enteral feeding was initiated on day 8. Despite nutritional management, there was a remarkable amyotrophy and weight loss. On day 85 in the ICU, the patient became progressively unresponsive. An extensive metabolic workup was performed, and blood results showed hyperammoniemia and hypertriglyceridemia. Plasma free carnitine level was low, as was also copper. After carnitine supplementation, the neurological condition rapidly improved, and metabolic perturbations regressed. Prolonged CRRT may be complicated by clinically significant deficiency in micronutrients and trace elements.

During the recent COVID-19 pandemic, the rapidly progressive shortage of intravenous sedative drugs led numerous intensive care units to look for potential alternatives in patients requiring mechanical ventilation for severe acute respiratory distress syndrome (ARDS). Inhalational sedation using the AnaConDa® device for sevoflurane administration is a possible option. In a 54-year-old COVID-19 patient with severe ARDS requiring extracorporeal membranous oxygenation (ECMO), sevoflurane on AnaConDa® device was administered for 8 days but was complicated by the development of nephrogenic diabetes insipidus (NDI). Other causes of NDI or central diabetes insipidus were reasonably excluded, as in other previously published cases of NDI in ICU patients receiving prolonged sevoflurane-based sedation. In addition, the postmortem examination suggested a lower expression of aquaporin-2 in renal tubules. This observation should prompt further investigations to elucidate the role of aquaporin-2 in sevoflurane-related NDI. Inhaled isoflurane sedation is a possible alternative.

Fire regimes across the world are expected to be altered by continuing variations in socio-economic conditions and climate. Current global fire-vegetation models are able to represent the present-day fire activity, but it is unclear how well they can simulate past or future scenarios. Here we use sedimentary charcoal-based biomass burning reconstructions to evaluate fire probability and total carbon flux emitted to the atmosphere per year simulated by the dynamic global vegetation model LPJ-GUESS with its incorporated fire model SIMFIRE-BLAZE across the boreal region during the last century. The analyses were run for the whole time period (1900–2000 CE), as well as for the intervals 1900–1950 CE and 1950–2000 CE. The data–model comparison for the 20th century reveals a general disagreement in trends between charcoal reconstructions (with decreasing or stable trends) and simulations (showing an overall increase) at both global (boreal forests) and continental scales (North America and Fennoscandia), as well as for most of the regional sub-areas (Canada, Norway and Sweden). The only exceptions are Alaska and Finland/Russia Karelia, where all the variables increase. Negative correlations between observations and model outputs are also recorded for the two different sub-periods, except for Alaska and North America during the time interval 1900–1950 CE, and Norway and Finland/Russia Karelia between 1950 and 2000 CE. Despite several uncertainties in charcoal records, main differences between modeled and observed fire activity are probably due to limitations in the representation of the human impact on fire regime (especially connected to forest management and landscape fragmentation) in the model simulations.

A 78-year-old woman was admitted for acute dyspnoea. One year before, she had been treated with cisplatin and gemcitabine for a high grade urothelial carcinoma. Immunotherapy was discussed 9 months later due the progression of bone metastases but could not be administered before this episode of respiratory distress. There was a major discrepancy between the findings of a limited pulmonary embolism at thoracic tomodensitometry and the severity of a recently developed pulmonary hypertension at echocardiography. The patient presented cardiac arrest on day 6 and post-mortem findings were consistent with diffuse pulmonary tumor thrombotic microangiopathy, a rare complication of urothelial carcinoma.

The case is reported of a 39-year-old severely obese woman who developed acute metabolic disorders after the administration of a short course of intravenous amiodarone. The main biological features were hypertriglyceridemia, hypoglycaemia, hyperlactatemia and hyperammonemia; all were reversible after amiodarone discontinuation. There was an associated rise in liver enzymes. However, the influence of co-factors on these metabolic disorders, such as acquired carnitine deficiency, severe obesity, a long-term course of pancreatitis, and abdominal infections, could not be excluded.

Understanding how fire regimes change over time is of major importance for understanding their future impact on the Earth system, including society. Large differences in simulated burned area between fire models show that there is substantial uncertainty associated with modelling global change impacts on fire regimes. We draw here on sensitivity simulations made by seven global dynamic vegetation models participating in the Fire Model Intercomparison Project (FireMIP) to understand how differences in models translate into differences in fire regime projections. The sensitivity experiments isolate the impact of the individual drivers on simulated burned area, which are prescribed in the simulations. Specifically these drivers are atmospheric CO2 concentration, population density, land-use change, lightning and climate. The seven models capture spatial patterns in burned area. However, they show considerable differences in the burned area trends since 1921. We analyse the trajectories of differences between the sensitivity and reference simulation to improve our understanding of what drives the global trends in burned area. Where it is possible, we link the inter-model differences to model assumptions. Overall, these analyses reveal that the largest uncertainties in simulating global historical burned area are related to the representation of anthropogenic ignitions and suppression and effects of land use on vegetation and fire. In line with previous studies this highlights the need to improve our understanding and model representation of the relationship between human activities and fire to improve our abilities to model fire within Earth system model applications. Only two models show a strong response to atmospheric CO2 concentration. The effects of changes in atmospheric CO2 concentration on fire are complex and quantitative information of how fuel loads and how flammability changes due to this factor is missing. The response to lightning on global scale is low. The response of burned area to climate is spatially heterogeneous and has a strong inter-annual variation. Climate is therefore likely more important than the other factors for short-term variations and extremes in burned area. This study provides a basis to understand the uncertainties in global fire modelling. Both improvements in process understanding and observational constraints reduce uncertainties in modelling burned area trends.

Fire emissions are a critical component of carbon and nutrient cycles and strongly affect climate and air quality. Dynamic global vegetation models (DGVMs) with interactive fire modeling provide important estimates for long-term and large-scale changes in fire emissions. Here we present the first multi-model estimates of global gridded historical fire emissions for 1700–2012, including carbon and 33 species of trace gases and aerosols. The dataset is based on simulations of nine DGVMs with different state-of-the-art global fire models that participated in the Fire Modeling Intercomparison Project (FireMIP), using the same and standardized protocols and forcing data, and the most up-to-date fire emission factor table based on field and laboratory studies in various land cover types. We evaluate the simulations of present-day fire emissions by comparing them with satellite-based products. The evaluation results show that most DGVMs simulate present-day global fire emission totals within the range of satellite-based products. They can capture the high emissions over the tropical savannas and low emissions over the arid and sparsely vegetated regions, and the main features of seasonality. However, most models fail to simulate the interannual variability, partly due to a lack of modeling peat fires and tropical deforestation fires. Before the 1850s, all models show only a weak trend in global fire emissions, which is consistent with the multi-source merged historical reconstructions used as input data for CMIP6. On the other hand, the trends are quite different among DGVMs for the 20th century, with some models showing an increase and others a decrease in fire emissions, mainly as a result of the discrepancy in their simulated responses to human population density change and land use and land cover change (LULCC). Our study provides an important dataset for further development of regional and global multi-source merged historical reconstructions, analyses of the historical changes in fire emissions and their uncertainties, and quantification of the role of fire emissions in the Earth system. It also highlights the importance of accurately modeling the responses of fire emissions to LULCC and population density change in reducing uncertainties in historical reconstructions of fire emissions and providing more reliable future projections.

Abstract In the last decade, our knowledge about OTC drug intoxication has been expanded much further relative to previous years, though the absence of antidotes in some cases results in healthcare professionals using symptomatic treatment. This case report reminds the reader of the importance of clinical and toxicology laboratories in the management of acute salicylate intoxication in order to avoid hemodialysis.

Abstract Background The primary endpoint was to investigate the prognostic factors of acute mesenteric ischemia (AMI) in ICU patients. Methods Retrospective observational, non-interventional, monocentric study of a cohort of 214 ICU patients with a confirmed diagnosis of arterial AMI. Results We collected demographics, mortality, hospital stay, prior medical history, comorbidities, reasons for ICU admission, laboratory investigations, diagnostic procedures, therapy, severity scores. The 30-day mortality rate was 71% for the 214 patients with arterial AMI. The incidence of nonocclusive mesenteric ischemia was particularly high. AMI was a secondary diagnosis in 58% of patients. Half of the population was represented by surgical patients who mostly required an urgent procedure. The mortality rate was not different in the subgroup with aortic surgery. Three factors were associated with an increase or decrease in mortality: the maximal dose of vasopressors (VP) administered to the patient (OR = 1.20; 95%CI = 1.08–1.33; p

Natural and human-ignited fires affect all major biomes, altering ecosystem structure, biogeochemical cycles and atmospheric composition. Satellite observations provide global data on spatiotemporal patterns of biomass burning and evidence for the rapid changes in global fire activity in response to land management and climate. Satellite imagery also provides detailed information on the daily or sub-daily position of fires that can be used to understand the dynamics of individual fires. The Global Fire Atlas is a new global dataset that tracks the dynamics of individual fires to determine the timing and location of ignitions, fire size and duration, and daily expansion, fire line length, speed, and direction of spread. Here, we present the underlying methodology and Global Fire Atlas results for 2003–2016 derived from daily moderate-resolution (500 m) Collection 6 MCD64A1 burned-area data. The algorithm identified 13.3 million individual fires over the study period, and estimated fire perimeters were in good agreement with independent data for the continental United States. A small number of large fires dominated sparsely populated arid and boreal ecosystems, while burned area in agricultural and other human-dominated landscapes was driven by high ignition densities that resulted in numerous smaller fires. Long-duration fires in boreal regions and natural landscapes in the humid tropics suggest that fire season length exerts a strong control on fire size and total burned area in these areas. In arid ecosystems with low fuel densities, high fire spread rates resulted in large, short-duration fires that quickly consumed available fuels. Importantly, multiday fires contributed the majority of burned area in all biomass burning regions. A first analysis of the largest, longest and fastest fires that occurred around the world revealed coherent regional patterns of extreme fires driven by large-scale climate forcing. Global Fire Atlas data are publicly available through http://www.globalfiredata.org (last access: 9 August 2018) and https://doi.org/10.3334/ORNLDAAC/1642, and individual fire information and summary data products provide new information for benchmarking fire models within ecosystem and Earth system models, understanding vegetation–fire feedbacks, improving global emissions estimates, and characterizing the changing role of fire in the Earth system.