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Time series of wetland methane fluxes measured by eddy covariance require gap-filling to estimate daily, seasonal, and annual emissions. Gap-filling methane fluxes is challenging because of high variability and complex responses to multiple drivers. To date, there is no widely established gap-filling standard for wetland methane fluxes, with regards both to the best model algorithms and predictors. This study synthesizes results of different gap-filling methods systematically applied at 17 wetland sites spanning boreal to tropical regions and including all major wetland classes and two rice paddies. Procedures are proposed for: 1) creating realistic artificial gap scenarios, 2) training and evaluating gap-filling models without overstating performance, and 3) predicting half-hourly methane fluxes and annual emissions with realistic uncertainty estimates. Performance is compared between a conventional method (marginal distribution sampling) and four machine learning algorithms. The conventional method achieved similar median performance as the machine learning models but was worse than the best machine learning models and relatively insensitive to predictor choices. Of the machine learning models, decision tree algorithms performed the best in cross-validation experiments, even with a baseline predictor set, and artificial neural networks showed comparable performance when using all predictors. Soil temperature was frequently the most important predictor whilst water table depth was important at sites with substantial water table fluctuations, highlighting the value of data on wetland soil conditions. Raw gap-filling uncertainties from the machine learning models were underestimated and we propose a method to calibrate uncertainties to observations. The python code for model development, evaluation, and uncertainty estimation is publicly available. This study outlines a modular and robust machine learning workflow and makes recommendations for, and evaluates an improved baseline of, methane gap-filling models that can be implemented in multi-site syntheses or standardized products from regional and global flux networks (e.g., FLUXNET). ISSN:0168-1923 ISSN:1873-2240

Spike detection for raw high-frequency eddy covariance time series is a challenging task because of the confounding effect caused by complex dynamics and the high level of noise affecting such data. To cope with these features, a new despiking procedure rooted on robust functionals is proposed. By processing simulated data, it is demonstrated that the proposed procedure performs better than the existing algorithms and can be therefore considered as a candidate for the implementation in data center environmental monitoring systems, where the availability of automatic procedures ensuring a high quality standard of released products constitutes an essential prerequisite.

Purpose To investigate the prevalence, incidence and characteristics of bacterial infections and their impact on outcome in critically ill patients infected with COVID-19. Methods We conducted a prospective observational study in eight Italian ICUs from February to May 2020; data were collected through an interactive electronic database. Kaplan–Meier analysis (limit product method) was used to identify the occurrence of infections and risk of acquisition. Results During the study period 248 patients were recruited in the eight participating ICUs. Ninety (36.3%) patients developed at least one episode of secondary infection. An ICU length of stay between 7 and 14 days was characterized by a higher occurrence of infectious complications, with ventilator-associated pneumonia being the most frequent. At least one course of antibiotic therapy was given to 161 (64.9%) patients. Overall ICU and hospital mortality were 33.9% and 42.9%, respectively. Patients developing bacteremia had a higher risk of ICU mortality [45.9% vs. 31.6%, odds ratio 1.8 (95% CI 0.9–3.7), p = 0.069] and hospital mortality [56.8% vs. 40.3%, odds ratio 1.9 (95% CI 1.1–3.9), p = 0.04]. Conclusion In critically ill patients infected with COVID-19 the incidence of bacterial infections is high and associated with worse outcomes. Regular microbiological surveillance and strict infection control measures are mandated. Supplementary Information The online version contains supplementary material available at 10.1007/s15010-021-01661-2.

Appropriate weaning is of crucial importance for critically ill patients requiring respiratory support. However, a remarkable proportion of them are difficult to wean. Levosimendan is a positive inotropic agent characterized by vasodilatory properties, which is used for the treatment of acute decompensated heart failure or in patients needing inotropic treatment, including cardiogenic shock, septic shock, pulmonary hypertension and right ventricular dysfunction, needed for hemodynamic support in patients with diuretic resistance, and weaning either from ventilator or from extracorporeal membrane oxygenation. This position paper will discuss the use of levosimendan in facilitating weaning from cardiorespiratory support in critically ill patients, according to available evidence and the personal experience of a group of Italian Experts.

The aorta is the largest artery in the body. It arises from the left ventricle, ascends for a short distance in the thorax, then forms an arch, and finally descends through the chest and through the abdomen, where it ends by dividing into two arteries called the common iliac arteries. Echocardiography is useful for every aortic disease that involves size, shape, and atherosclerotic degeneration of the thoracic aorta. With transesophageal echocardiography we can easily visualize and study the aortic root and the proximal ascending aorta, and transesophageal echocardiography can resolve the technical limitation of transthoracic echocardiography in the examination of the thoracic aorta.

One of the most significant indicators for assessing the quality of university careers is the dropout rate between the first and second year. Both literature on the subjects and the results that emerged from numerous specific investigations into the dropouts of the university system, showed the crucial importance of this junction between the first and the second year. Reasons for dropping out can be quite varied, ranging from incorrect and/or insufficient prospective student orientation, the willingness or need to find a job as quickly as possible, to a lack of awareness of not being able to cope with a particular course of study rather than another. In this paper we focus specifically on the problem of dropouts in Italy, addressing it from a dual point of view. At an aggregate level, the analysis deals with dropout rates in Italy between the first and second year, in order to identify the main trends and dynamics at the national level. Subsequently, we analyze individual-level data from the University of Bari Aldo Moro, aiming to identify the most important contributing factors. This individual-level approach has emerged over recent years, and is generally known as ‘Educational Data Mining’, focused on the development of ad hoc methods that can be used to discover regularities and new information within databases from contexts related to education. Using supervised classification methods, we are able to identify retrospectively the profile of students who are most likely to dropout.

Research infrastructures play a key role in launching a new generation of integrated long-term, geographically distributed observation programmes designed to monitor climate change, better understand its impacts on global ecosystems, and evaluate possible mitigation and adaptation strategies. The pan-European Integrated Carbon Observation System combines carbon and greenhouse gas (GHG; CO2, CH4, N2O, H2O) observations within the atmosphere, terrestrial ecosystems and oceans. High-precision measurements are obtained using standardised methodologies, are centrally processed and openly available in a traceable and verifiable fashion in combination with detailed metadata. The Integrated Carbon Observation System ecosystem station network aims to sample climate and land-cover variability across Europe. In addition to GHG flux measurements, a large set of complementary data (including management practices, vegetation and soil characteristics) is collected to support the interpretation, spatial upscaling and modelling of observed ecosystem carbon and GHG dynamics. The applied sampling design was developed and formulated in protocols by the scientific community, representing a trade-off between an ideal dataset and practical feasibility. The use of open-access, high-quality and multi-level data products by different user communities is crucial for the Integrated Carbon Observation System in order to achieve its scientific potential and societal value.

Background Whether intracoronary plasma adiponectin levels may vary in the presence of coronary artery disease and change after coronary revascularization is unexplored. Aim We evaluated plasma adiponectin levels in peripheral vein and coronary circulation before and after coronary artery bypass graft (CABG) in patients with CAD and without CAD (no CAD). Methods We examined 12 patients with CAD who required CABG and 10 patients with non-CAD who underwent cardiac surgery for valve replacement. Peripheral plasma adiponectin and intracoronary adiponectin levels were measured in left coronary artery (LCA) and great cardiac vein (GCV) during coronary angiography at baseline, 24 h and 7 days after cardiac surgery. Results Peripheral and GCV and LCA plasma adiponectin levels were significantly lower in CAD than non-CAD patients (6±3 vs 12±5, p p p p p p Conclusions Our study shows that intracoronary plasma adiponectin is lower in CAD than in no CAD subjects, but rapidly and significantly increases after CABG.

The calcium sensitizer levosimendan has anti-ischaemic effects mediated via the opening of sarcolemmal and mitochondrial ATP-sensitive potassium channels. These properties suggest potential application in clinical situations where cardioprotection would be beneficial, such as cardiac surgery. We thus decided to investigate whether pharmacological pre-treatment with levosimendan reduces intensive care unit (ICU) length of stay in patients undergoing elective myocardial revascularization under cardiopulmonary bypass.One hundred and six patients undergoing elective coronary artery bypass grafting were randomly assigned in a double-blind manner to receive levosimendan or placebo. Levosimendan (24 microg kg(-1)) or placebo was administered as a slow i.v. bolus over a 10 min period before the initiation of bypass.Tracheal intubation time and the length of ICU stay were significantly reduced in the levosimendan group (P0.01). The number of patients needing inotropic support for12 h was significantly higher in the control group (18.0% vs 3.8%; P=0.021). Compared with control patients, levosimendan-treated patients had lower postoperative troponin I concentrations (P0.0001) and a higher cardiac power index (P0.0001).Pre-treatment with levosimendan in patients undergoing surgical myocardial revascularization resulted in less myocardial injury, a reduction in tracheal intubation time, less requirement for inotropic support, and a shorter length of ICU stay.

Objective: The aim of this study was to assess safety and effectiveness of recombinant activated factor VII (rFVIIa) in patients with refractory bleeding undergoing acute aortic dissection surgery with deep hypothermic circulatory arrest. Design: Propensity score-matched analysis. Setting: University hospital. Patients: Twenty-three cardiac surgery patients receiving rF-VIIa compared with 23 matched controls. Interventions: An intravenous bolus of rFVIIa (70 mu g/kg) was administered at the end of a complete transfusion protocol. Five patients received rFVIIa in the operating room, and 18 patients received rFVIIa in the intensive care unit. Four of the intensive care unit patients required a second dose. Measurements and Main Results: Blood loss and transfusion requirements were significantly reduced in the period after rFVIIa administration. A highly significant reduction in hourly blood loss was found at -1 hr vs. 0 hrs and 0 hrs vs. 1 hr (-194 and -77.5 mL, respectively; both adjusted p < .001). In addition, significant improvements of international normalized ratio (p < .001), partial thromboplastin time (p < .001), platelet count (p < .001), fibrinogen (p < .001), and antithrombin (p < .001) were detected after rFVIIa administration. The two groups did not differ regarding adverse events. Conclusions: rFVIIa was successfully used as an additional therapy both during and after acute aortic dissection surgery with deep hypothermic circulatory arrest, when bleeding was refractory to conventional methods. Randomized studies are necessary to confirm the safety and efficacy of rFVIIa in this setting.

Background The calcium sensitizer levosimendan protects against myocardial ischaemia and reperfusion injury in animal models. Methods The present pilot study investigated whether a short infusion before coronary artery bypass grafting (CABG) would protect the myocardium and improve postoperative haemodynamics. Twenty-four patients with stable angina undergoing elective CABG surgery were randomized to receive either placebo or levosimendan (24 µg kg−1) infused i.v. over a 10 min period just before placing the patient on cardiopulmonary bypass. Results Perioperative haemodynamic variables, concentrations of cardiac troponin I over the 48 h postoperative period, and clinical outcomes were assessed. There were no adverse effects related to levosimendan. Compared with control patients, levosimendan-treated patients had lower postoperative troponin I concentrations (P Conclusion Patients receiving a short infusion of levosimendan before CABG showed evidence of less myocardial damage, suggestive of a preconditioning effect. Larger outcome studies are thus indicated to confirm benefit.

Objective The aim was to investigate perioperative factors associated with the development of post-traumatic stress disorder (PTSD) in patients who underwent cardiac surgery. Design Prospective observational study. Setting Single academic center. Participants One hundred twenty-eight consecutive patients scheduled for elective cardiac surgery with cardiopulmonary bypass. Interventions Patients were interviewed within the surgical unit 1 to 3 days before cardiac surgery. Measurements and Main Results Six months after surgery, participants were mailed the modified version of the Posttraumatic Stress Symptom Inventory 10. Of the 71 patients who completed the questionnaire and mailed it back at follow-up, 14 (19.7%) received a diagnosis of PTSD. Seven of 13 female patients who were not treated with β-blockers received a diagnosis of PTSD compared with 0 of 12 who were treated with β-blockers (p = 0.005, Fisher exact test). In a general linear model, including sex and β-blocker treatment as predictors, the Posttraumatic Stress Symptom Inventory 10 score was significantly predicted by β-blockade (F = 4.74, p = 0.033), with a significant interaction between sex and β-blockade (F = 9.72, p = 0.003). Conclusions These findings suggest that the use of β-blockers might be protective against the development of PTSD in women after cardiac surgery.

It has been extensively demonstrated that an elevated heart rate is a modifiable, independent risk factor for cardiovascular events. A high heart rate increases myocardial oxygen consumption and reduces diastolic perfusion time. It can also increase ventricular diastolic pressures and induce ventricular arrhythmias. Critical care patients are prone to develop a stress induced cardiac impairment and consequently an increase in sympathetic tone. This in turn increases heart rate. In this setting, however, heart rate lowering might be difficult because the effects of inotropic drugs could be hindered by heart rate reducing drugs like beta-blockers. Ivabradine is a new selective antagonist of funny channels. It lowers heart rate, reducing the diastolic depolarization slope. Moreover, ivabradine is not active on sympathetic pathways, thus avoiding any interference with inotropic amines. We reviewed the literature available regarding heart rate control in critical care patients, focusing our interest on the use of ivabradine to assess the potential benefits of the drug in this particular setting.

This study aims to evaluate the potential effects of the climatic variations on the reference evapotranspiration (ET0) and, consequently, on the crop water requirements in the Apulian Tavoliere, one of the largest irrigated districts of Southern Italy. To reach this purpose, both climatic parameters (air temperature and rainfall) and estimated water requirements of ‘processing’ tomato (among the most representative irrigated crops in the district since the mid-1970s and, therefore, chosen as a study-case) were analyzed in order to find out if a time trend exists or does not. The analysis covered the period from 1957 to 2008. The analysis showed that the rainfall amounts decreased (−3.4 mm per year in the analyzed period), while air temperature increased (0.18 °C and 0.25−°C per decade for minimum and maximum, respectively). As a consequence of the climatic variation during the considered period, a growth trend of the ET0 (1.4 mm per year) and water deficit (3.2 mm per year) took place. As a consequence, the water amounts for irrigating the same crop in the considered period were growing. This increased consumption is in agreement with the perception of the farmers of the district but never documented. Through the FAO AquaCrop model, the tomato irrigation water requirements have been simulated during the considered period. The trend analysis of the seasonal evapotranspiration values simulated in 52 years confirmed the increase in tomato water requirements (0.7 mm per year).

The impacts of the climate change for agriculture is an ambitious and unresolved topic due to the complexity of the natural phenomena. The high variability of the Mediterranean basin does not allow us to generalize with enough certainty the results obtained from other researches and other locations. Therefore, a site specific analysis in Capitanata plain was conducted. The aim is to provide a detailed picture of recent change in climate regime in one of the most important agricultural area of South Italy. Climate analysis was carried out and several indices of extreme events were studied on the basis of temperature and precipitation observations registered at experimental station ‘Podere 124’ (CRA-SCA). The period under study is 1979-2008. Increasing trends were identified for the summer season with an intensification of the number of heat waves.

The aim of the study was to test 1) whether chronic and stable coronary artery disease (CAD) could downregulate epicardial fat adrenomedullin synthesis and secretion, and decrease intracoronary plasma adrenomedullin levels, and 2) whether intracoronary plasma adrenomedullin levels could be related to epicardial adipose tissue adrenomedullin gene and protein expression in subjects with CAD. We examined 12 patients with CAD who required coronary artery bypass graft (CABG) and 10 patients with non-CAD who underwent cardiac surgery for valve replacement. Plasma levels of adrenomedullin were measured in peripheral vein circulation, in left coronary artery (LCA) and coronary sinus (CS) during coronary angiography. Epicardial adipose tissue biopsy for Reverse Transcription and Real-Time PCR (RT-PCR) adrenomedullin mRNA analysis and Western Blotting (WB) protein expression was performed during cardiac surgery in all subjects. Peripheral, LCA, and CS plasma adrenomedullin levels were significantly lower in CAD patients than in those with non-CAD (3.0+/-0.9 vs. 4.4+/-0.9 pg/ml p

The aim of this study was to compare the positive inotropic effects of 3 different agents with 3 different mechanisms of actions-levosimendan, rolipram, and dobutamine-on human atrial trabecular muscles. Samples of right atrial appendage (1 cm, 500-1000 mg) were removed and immersed in preoxygenated and modified Tyrode solution. In oxygenated Tyrode solution, preparations were used to investigate the concentration-effect relationship of levosimendan, dobutamine, and rolipram on percentage developed tension (DT), from 10 to 10 M, each concentration for 15 minutes. All 3 agents produced concentration-dependent increments in DT. We found that levosimendan was the most efficacious positive inotropic agent on isolated human atrial trabeculae. Both the sensitivity (pD2) and maximum response (Emax) of human atrial trabeculae to levosimendan (6.711 +/- 0.26 and 23.2 +/- 2.2 mN, respectively) were significantly greater than those of dobutamine (6.663 +/- 0.19 and 17.6 +/- 2.8 mN) and rolipram (6.497 +/- 0.18 and 15.0 +/- 1.0 mN). pD2 and Emax values for dobutamine were significantly higher than those for rolipram. It was suggested that because of its potential to enhance cardiac performance without predisposition to calcium-induced arrhythmias, levosimendan might be more useful as a positive inotropic agent in clinical practice.

We report a novel case of multiple endocrine neoplasia type 2A (MEN 2A) associated with two mutations of the protooncogene RET. One affects codon 634 and causes a cysteine to arginine substitution; the second at codon 640 causes an alanine to glycine substitution in the transmembrane region. The two mutations were present on the same RET allele and were detected in germline and tumor DNA. Both mutations were de novo, i.e. they were not found in the DNA of the parents or relatives. Immunohistochemical and RT-PCR analysis showed that the pheochromocytoma expressed calcitonin as well as both RET alleles. A cell line established from the tumor and propagated in culture sustained the expression of RET and calcitonin, as did the original pheochromocytoma. Because the patient presented with medullary thyroid carcinoma and pheochromocytoma without parathyroid gland involvement, we speculate that this clinical picture could be correlated with the two RET mutations and to the unusual calcitonin production. This is the first report of a MEN 2A case due to two mutations of the RET gene and associated with a calcitonin-producing pheochromocytoma.