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A global in situ data set for validation of ocean colour products from the ESA Ocean Colour Climate Change Initiative (OC-CCI) is presented. This version of the compilation, starting in 1997, now extends to 2021, which is important for the validation of the most recent satellite optical sensors such as Sentinel 3B OLCI and NOAA-20 VIIRS. The data set comprises in situ observations of the following variables: spectral remote-sensing reflectance, concentration of chlorophyll-a, spectral inherent optical properties, spectral diffuse attenuation coefficient, and total suspended matter. Data were obtained from multi-project archives acquired via open internet services or from individual projects acquired directly from data providers. Methodologies were implemented for homogenization, quality control, and merging of all data. Minimal changes were made on the original data, other than conversion to a standard format, elimination of some points, after quality control and averaging of observations that were close in time and space. The result is a merged table available in text format. Overall, the size of the data set grew with 148 432 rows, with each row representing a unique station in space and time (cf. 136 250 rows in previous version; Valente et al., 2019). Observations of remote-sensing reflectance increased to 68 641 (cf. 59 781 in previous version; Valente et al., 2019). There was also a near tenfold increase in chlorophyll data since 2016. Metadata of each in situ measurement (original source, cruise or experiment, principal investigator) are included in the final table. By making the metadata available, provenance is better documented and it is also possible to analyse each set of data separately. The compiled data are available at https://doi.org/10.1594/PANGAEA.941318 (Valente et al., 2022).

A global compilation of in situ data is useful to evaluate the quality of ocean-colour satellite data records. Here we describe the data compiled for the validation of the ocean-colour products from the ESA Ocean Colour Climate Change Initiative (OC-CCI). The data were acquired from several sources (including, inter alia, MOBY, BOUSSOLE, AERONET-OC, SeaBASS, NOMAD, MERMAID, AMT, ICES, HOT and GeP&CO) and span the period from 1997 to 2018. Observations of the following variables were compiled: spectral remote-sensing reflectances, concentrations of chlorophyll a, spectral inherent optical properties, spectral diffuse attenuation coefficients and total suspended matter. The data were from multi-project archives acquired via open internet services or from individual projects, acquired directly from data providers. Methodologies were implemented for homogenization, quality control and merging of all data. No changes were made to the original data, other than averaging of observations that were close in time and space, elimination of some points after quality control and conversion to a standard format. The final result is a merged table designed for validation of satellite-derived ocean-colour products and available in text format. Metadata of each in situ measurement (original source, cruise or experiment, principal investigator) was propagated throughout the work and made available in the final table. By making the metadata available, provenance is better documented, and it is also possible to analyse each set of data separately. This paper also describes the changes that were made to the compilation in relation to the previous version (Valente et al., 2016). The compiled data are available at https://doi.org/10.1594/PANGAEA.898188 (Valente et al., 2019).

A compiled set of in situ data is important to evaluate the quality of ocean-colour satellite-data records. Here we describe the data compiled for the validation of the ocean-colour products from the ESA Ocean Colour Climate Change Initiative (OC-CCI). The data were acquired from several sources (MOBY, BOUSSOLE, AERONET-OC, SeaBASS, NOMAD, MERMAID, AMT, ICES, HOT, GeP&CO), span between 1997 and 2012, and have a global distribution. Observations of the following variables were compiled: spectral remote-sensing reflectances, concentrations of chlorophyll a, spectral inherent optical properties and spectral diffuse attenuation coefficients. The data were from multi-project archives acquired via the open internet services or from individual projects, acquired directly from data providers. Methodologies were implemented for homogenisation, quality control and merging of all data. No changes were made to the original data, other than averaging of observations that were close in time and space, elimination of some points after quality control and conversion to a standard format. The final result is a merged table designed for validation of satellite-derived ocean-colour products and available in text format. Metadata of each in situ measurement (original source, cruise or experiment, principal investigator) were preserved throughout the work and made available in the final table. Using all the data in a validation exercise increases the number of matchups and enhances the representativeness of different marine regimes. By making available the metadata, it is also possible to analyse each set of data separately. The compiled data are available at doi:10.1594/PANGAEA.854832 (Valente et al., 2015).

The accuracy of marine data products from the Medium Resolution Imaging Spectrometer (MERIS) operated on board the Envisat platform is investigated with the aid of in situ geographically distributed measurements from different European seas. The assessment focuses on standard products from the 2012 data update commonly identified as 3rd Reprocessing. Results indicate atmospherically corrected data affected by a negative bias of several tens percent at the 413 nm center wavelength, significantly decreasing to a few percent at 560 nm and increasing again at 665 nm. Such an underestimate at the blue center wavelengths leads to an average overestimate of the algal-1 MERIS pigment index largely exceeding 100% for the considered European seas. A comparable overestimate is also observed for the algal-2 pigment index independently determined from top-of-atmosphere radiance through the application of neural networks.

OECD/NEA has initiated an international Uncertainty Analysis in Modeling (UAM) benchmark focused on uncertainties in modeling of Light Water Reactor (LWR). The first step of uncertainty propagation is to perform sensitivity to the input data affected by the numerical errors and physical models. The objective of the present paper is to study the effect of the numerical discretization error and the manufacturing tolerances on fuel pin lattice integral parameters (multiplication factor and macroscopic cross-sections) through sensitivity calculations. The two-dimensional deterministic codes NEWT and HELIOS were selected for this work. The NEWT code was used for analysis of the TMI-1, PB-2, and Kozloduy-6 test cases; the TMI-1 test case was investigated using the HELIOS code. The work has been performed within the framework of UAM Exercise I-1 “Cell Physics.”

Cyanobacterial blooms in lakes have increased in frequency and intensity over the past two decades, negatively affecting ecological and biogeochemical processes. This study focuses on the phytoplankton composition of Lake Maggiore, with a special emphasis on cyanobacteria detection through pigment composition. While microscopy is the standard method for phytoplankton identification, pigment-based methods provide broader spatiotemporal coverage. Between May and September 2023, five measurement campaigns were conducted in Lake Maggiore, collecting bio-geochemical and bio-optical data at 27 stations. The total Chlorophyll-a (TChl a ) was measured, with concentrations ranging from 1.13 to 6.9 mg/m 3 . Phytoplankton pigment composition was analyzed using High-Performance Liquid Chromatography (HPLC) and the CHEMTAX approach was applied for phytoplankton classification. The results were cross-validated using Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and microscopic counts. Cyanobacteria were identified based on unique pigment markers, such as carotenoids. The HPLC-derived pigment classification results aligned well with both PCA and HCA and microscopic counts verified the accuracy of the pigment-based chemotaxonomy. The study demonstrates that pigment-based classification methods, when combined with statistical analyses, offer a reliable alternative for identifying cyanobacteria and other phytoplankton groups, with potential applications in support of remote sensing algorithm development.

Background: Patients with recent-onset atrial fibrillation (AF) and cardiac troponin I (cTnI) elevations show poor outcomes. Coronary heart disease might be a cause, consequence, or an innocent bystander., Objective: The aim of this study was to recognize and treat coronary heart disease to avoid adverse events., Methods: Patients with recent-onset AF participated in the study. The exclusion criteria were acute coronary syndrome and severe comorbidities. Patients managed with standard care (group 1, n=1086, years 2010-2011) were compared with patients managed with tailored care inclusive of echocardiography and stress testing when required (group 2, n=1055, years 2012-2013)., Endpoint: The endpoint was a composite of ischemic vascular events including stroke, acute coronary syndrome, revascularization and cardiovascular death at 6 months of follow-up., Results: Of 4008 patients considered, 2141 were enrolled; 183 showed cTnI elevations, 92 in group 1 and 91 in group 2. cTnI elevations, known ischemic heart disease and age were predictors of the endpoint on multivariate analysis. Overall, two versus seven patients (P=0.033) in groups 1 and 2, respectively, underwent revascularization. Eventually, 16 patients in group 1 versus five patients in group 2 reached the endpoint (P=0.019). Patients of group 2 were managed as follow: 35 were admitted, 15 with positive stress testing and 20 with high cTnI values (mean values: 0.64±1.01 ng/ml). Fifty-six patients were discharged with negative stress testing results (n=13) or very low cTnI values (n=43, mean values 0.29±0.30 ng/ml)., Conclusion: In patients with AF and cTnI elevations, tailored care inclusive of echocardiography and stress testing succeeded in recognizing and treating masked 'critical' coronary heart disease, avoiding adverse events.

Objective: To update the prognostic value of scan strategy with pharmacological stress agent in chest pain (CP) patients presenting with normal electrocardiography (ECG) and troponin., Methods: Two consecutive nonrandomized series of patients with CP and negative first-line workup inclusive of serial ECG, serial troponin, and echocardiography underwent myocardial perfusion imaging single photon emission computed tomography (SPECT) in the emergency department. Of 170 patients enrolled, 52 patients underwent dipyridamole-SPECT and 118 adenosine-SPECT. Patients with perfusion defects underwent angiography, whereas the remaining patients were discharged and followed-up. Primary endpoint was the composite of nonfatal myocardial infarction, unstable angina, revascularization, and cardiovascular death at follow-up or the presence of coronary stenosis > 50% at angiography., Results: At multivariate analysis, the presence of perfusion defects or hypertension was independent predictor of the primary endpoint. Sensitivity and negative predictive value were higher in patients subjected to adenosine-SPECT (95% and 99%, respectively) versus dipyridamole-SPECT (56% and 89%; yield 70% and 11%, respectively; P < 0.03). Of note, sensitivity, negative, and positive predictive values were high in patients with hypertension (100%, 93%, and 60%, respectively) or nonischemic echocardiography alterations (100%, 100%, and 100%, respectively)., Conclusions: In CP patients, presenting with normal ECG and troponin, adenosine-SPECT adds incremental prognostic values to dipyridamole-SPECT. Costly scan strategy is more appropriate and avoids unnecessary angiograms in patients with hypertension or nonischemic echocardiography alterations.

Water-soluble polar organic contaminants are discharged by rivers, cities, and ships into the oceans. Little is known on the fate, pollution effects, and thresholds of toxic chemical mixtures in the marine environment. A new trace analytical method was developed for the multi-compound analysis of polar organic chemical contaminants in marine waters. The method is based on automated solid-phase extraction (SPE) of one-liter water samples followed by ultrahigh-pressure liquid chromatography triple-quadrupole linear ion-trap mass spectrometry (UHPLC-QTRAP(®) MS). Marine water samples from the open Adriatic Sea taken 16 km offshore from Venice (Italy) were analyzed. Method limits of quantification (LOQs) in the low picogram per liter (pg/l) concentration range were achieved. Among the 67 target chemicals analyzed, 45 substances could be detected above the LOQ. The chemicals detected at the highest concentrations were caffeine (up to 367 ng/l), nitrophenol (36 ng/l), 2,4-dinitrophenol (34 ng/l), 5-methyl-1H-benzotriazole (18.5 ng/l), sucralose (11 ng/l), 1H-benzotriazole (9.2 ng/l), terbuthylazine (9 ng/l), alachlor (7.7 ng/l), atrazine-desisopropyl (6.6 ng/l), diethyltoluamide (DEET) (5.0 ng/l), terbuthylazine-desethyl (4.3 ng/l), metolachlor (2.8 ng/l), perfluorooctanoic acid (PFOA) (2.5 ng/l), perfluoropentanoic acid (PFPeA) (2.3 ng/l), linuron (2.3 ng/l), perfluorohexanoic acid (PFHxA) (2.2 ng/l), diuron (2.0 ng/l), perfluorohexane sulfonate (PFHxS) (1.6 ng/l), simazine (1.6 ng/l), atrazine (1.5 ng/l), and perfluorooctane sulfonate (PFOS) (1.3 ng/l). Higher concentrations were detected during summer due to increased levels of tourist activity during this period.

Aim: Aggressive approach in patients presenting atrial fibrillation (AF) and hypertension could result in improving rhythm control and reducing admission., Methods: Out of 3475 patients presenting AF, those with hypertension (n=1739, 52%) underwent standard (n=591, group 1, years 2004-2005) or aggressive pharmacological and electrical approach (n=1148, group 2, years 2006-2009). Overall, in 1071 patients AF duration was less than 48 h. Primary endpoint was rhythm conversion; secondary endpoints were modalities of rhythm conversion and reduction of admissions., Results: At univariate and multivariate analyses, AF lasting less than 48 h, absence of comorbidities and younger age were independent predictors of sinus rhythm; conversely, lack of sinus rhythm, older age, AF lasting more than 48 h and comorbidities were independent predictors of hospitalization. Overall, 55% of patients achieved sinus rhythm in group 1 versus 62% in group 2 (p=0.018). Interestingly, in patients with AF lasting less than 48 h, 89% achieved sinus rhythm, more likely by class 1C than by class III antiarrhythmic drugs (p<0.001). Overall reduction of admission accounts for 60%; 50% of patients need admission in group 1 versus 29% in group 2 (p<0.001)., Conclusions: Aggressive pharmacological and electrical approach in patients presenting AF and hypertension significantly improved rhythm conversion overall up to 62%. Patients with AF lasting less than 48 h eventually achieved sinus rhythm up to 89%, mostly by class IC antiarrhythmic drugs. Admissions eventually reduced up to 60%., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: Several risk scores are available for prognostic purpose in patients presenting with chest pain., Aim: The aim of this study was to compare Grace, Pursuit, Thrombolysis in Myocardial Infarction (TIMI), Goldman, Sanchis, and Florence Prediction Rule (FPR) to exercise electrocardiogram (ECG), decision making, and outcome in the emergency setting., Methods: Patients with nondiagnostic ECGs and normal troponins and without history of coronary disease underwent exercise ECG. Patients with positive testing underwent coronary angiography; otherwise, they were discharged. End point was the composite of coronary stenosis at angiography or cardiovascular death, myocardial infarction, angina, and revascularization at 12-month follow-up., Results: Of 508 patients considered, 320 had no history of coronary disease: 29 were unable to perform exercise testing, and finally, 291 were enrolled. Areas under the receiver operating characteristic curves for Grace, Pursuit, TIMI, Goldman, Sanchis, and FPR were 0.59, 0.68, 0.69, 0.543, 0.66, and 0.74, respectively (P < .05 FPR vs Goldman and Grace). In patients with negative exercise ECG and overall low risk score, only the FPR effectively succeeded in recognizing those who achieved the end point; in patients with high risk score, the additional presence of carotid stenosis and recurrent angina predicted the end point (odds ratio, 12 and 5, respectively). Overall, logistic regression analysis including exercise ECG, coronary risk factors, and risk scores showed that exercise ECG was an independent predictor of coronary events (P < .001)., Conclusions: The FPR effectively succeeds in ruling out coronary events in patients categorized with overall low risk score. Exercise ECG, nonetheless being an independent predictor of coronary events could be considered questionable in this subset of patients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Novel facilities such as an intensive observation unit and an outpatient clinic could result in improving management of patients presenting with atrial fibrillation (AF)., Methods: This observational study enrolled 3475 patients. Group 1 (1120 patients; years 2004-2005) was managed with standard approach; group 2 (992 patients; years 2006-2007) was managed with additional intensive observation; group 3 (1363 patients; years 2008-2009) was managed with additional intensive observation and outpatient clinic. Primary end point was admission to hospital. Secondary end points included modalities of rhythm conversion and administration of class IC vs class III antiarrhythmic drugs in patients with AF lasting less than 48 hours., Results: Lack of rhythm control, comorbidities, diabetes, and age were independent predictors of hospitalization. Admissions significantly decreased from group 1 (50%) to 2 (38%) and to 3 (24%) (P < .001). Interestingly, more than a quarter of patients in group 3 were referred to the outpatient clinic for short-term follow-up, eventually avoiding admission. Patients with AF lasting less than 48 hours (n = 2189) and without structural heart disease (n = 1685) achieved sinus rhythm in 89% of cases and were discharged. In these patients, early administration of antiarrhythmic drugs of class IC and III gained sinus rhythm in 80% and 20%, respectively (P < .001). Spontaneous conversion occurred in 26%; electrical, 17%; and pharmacological, 57%., Conclusions: In patients with AF, beyond the standard approach, the novel organization with an additional intensive observation unit for early pharmacological interventions and an outpatient clinic for elective treatment and short-term follow-up significantly reduced admission irrespective of independent predictors of hospitalizations. Patients without structural heart disease treated with antiarrhythmic drugs achieved sinus rhythm in 89% of cases, mostly with class IC drugs., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The delivery and accumulation of PCDD/Fs and dioxin-like PCBs (DL-PCBs) as recorded in sediments from the Lake Maggiore (LM) in Northern Italy and the influence of the atmosphere in contaminating this subalpine ecosystem were studied. PCDD/Fs (17 congeners) and DL-PCBs (12 congeners) concentrations, congener profiles and fluxes in air, bulk deposition, aquatic settling material and surface sediments are presented. Our strategy was to obtain surface sediment from areas near riverine inputs and in the depositional basins, settling material in sediment traps at one site and air, aerosol and bulk deposition profiles. PCDD/F concentrations in air of 25 WHO-TEQ fg m(-3) and DL-PCBs of 7 WHO-TEQ fg m(-3) were measured. Bulk atmospheric deposition yielded 140 and 28 WHO-TEQ pg m(-2) per week for dioxins/furans and DL-PCBs, respectively. Aquatic settling material exhibited concentrations of 11 WHO-TEQ pg g(-1) for PCDD/Fs and 2 WHO-TEQ pg g(-1) for DL-PCBs. Weekly settling material fluxes of 50 WHO-TEQ pg m(-2) and 10 WHO-TEQ pg m(-2) were obtained for PCDD/Fs and DL-PCBs, respectively. PCDD/Fs concentrations in surface sediments varied from 0.1 to 17 WHO-TEQ pg g(-1) whereas values ranged from 0.03 to 6 WHO-TEQ pg g(-1) for DL-PCBs. The concentrations obtained in the environmental compartments studied suggest a situation of low level contamination. PCDD/Fs and DL-PCBs congener profiles in atmospheric air, bulk deposition, aquatic settling matter and surface sediment point to an important if not dominant contribution from atmospheric deposition to Lake Maggiore, especially derived from wet deposition of aerosol-bound PCDD/Fs and DL-PCBs. Flux estimates support this hypothesis.

Large lakes are sinks for many chemical pollutants but the role of the atmosphere in delivering PBDEs (polybrominated diphenyl ethers) is not well known. In this study we estimated inputs of PBDEs from the atmosphere to Lake Maggiore and the delivery via settling material to accumulated bottom sediments. Sampling consisted of one simultaneous week of air and bulk deposition during Spring 2005, an integrated 4-month period of collected settling material (via sediment trap), and superficial bottom sediments near the sediment trap deployment and tributary mouths of the lake. Concentration of total PBDEs (Sigma 8) in the sediments ranged between 0.06 and 27 ng g(-1), and two different patterns were observed. One pattern was dominated by BDE-47 and BDE-99 and a second by BDE-209. The latter pattern suggested input from local source(s). Total PBDEs in air were 107 pg m(-3) with a pattern dominated by BDE-47. The bulk deposition rate of total PBDEs for precipitation was measurated to be 17.6 ng m(-2) day(-1) where BDE-209 exhibited the highest concentration. For aquatic settling material the flux was 3.57 ng m(-2) day(-1) and was dominated by congeners BDE-47 and BDE-99. The bulk deposition and settling material fluxes were in the same range for the less brominated congeners, while for the hepta- and deca-brominated PBDEs the fluxes in the settling material were one order of magnitude lower. This suggests different sedimentation processes among congeners and/or the presence of local sources that influence the relative distribution in water column.

This study assesses the status of Sacca di Goro coastal lagoon (Northern Adriatic, Italy) with respect to watershed pollution. Because 80% of its watershed is devoted to agriculture, plant protection products and their metabolites were found in the water column, sediments (the upper 0-15 cm layer), macroalgae (Ulva rigida) and clams (Tapes philippinarum). Five seasonal sampling campaigns were performed from May 2004 to April 2005 and concentrations measured in five stations in the lagoon and six in the watershed. Relatively high concentrations of the s-triazine - terbuthylazine -, urea herbicides - diuron - and alachlor were detected through the year mainly at stations directly influenced by the Po di Volano inflow. The concentrations of products in use follow a clear seasonal pattern with spring peaks. This pattern is also visible in the sediments as well as in biota. Among metabolites, hydroxylated compounds prevailed, often with concentrations greater than those of the parent compounds. For the most part of the year, the concentrations in biota were close to detection limits, with concentration peaks in spring.

Samples of air (gas and particulate phases), bulk deposition, aquatic settling material and sediments were collected in Lake Maggiore (LM) in order to determine their content of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Air (gas and particulate phases) concentrations were 0.5 pg m(-3), 80 pg m(-3), 13 pg m(-3) and 106 pg m(-3) for SigmaPCDD/Fs, SigmaPCBs, Sigma dioxin-like PCBs (DL-PCBs) and SigmaPBDEs, respectively. Deposition fluxes ranged from 0.7 ng m(-2) d(-1) for SigmaPCDD/Fs to 32 ng m(-2) d(-1) for SigmaPCBs. Aquatic settling material presented concentrations of 0.4 ng g(-1) dry weight (dw) for SigmaPCDD/Fs, 13 ng g(-1) dw for SigmaPCB, 3.4 ng g(-1) dw for SigmaDL-PCBs and 5.7 ng g(-1) dw for SigmaPBDEs. Mean sediment concentrations were 0.4 ng g(-1) dw for SigmaPCDD/Fs, 11 ng g(-1) dw for SigmaPCB, 3 ng g(-1) dw for SigmaDL-PCBs and 5.1 ng g(-1) dw for SigmaPBDEs. Similar PCDD/F and DL-PCB congener patterns in all the environmental compartments of LM point to an important, if not dominant, contribution of atmospheric deposition as source of these pollutants into LM. In contrast, PBDE congener distribution was not similar in the different environmental compartments. BDE 47 dominated air and settling material, while BDE 209 was the predominant congener in the bulk atmospheric deposition. Moreover, sediments showed two distinct PBDE congener profiles. Lower PBDE concentrated sediments were dominated by congeners 47 and 99, while BDE 209 dominated in higher PBDE concentrated samples. This suggests the influence of local sources as well as atmospheric input of PBDEs into LM.

Sacca di Goro is a shallow coastal microtidal lagoon with a surface area of 26 km2, and an average depth of about 1.5m. Fresh water pollutant loads from Po River branches and several drainage canals lead to anthropogenic eutrophication, frequent summer anoxia crises and chemical contamination. Such events not only affect the lagoon ecosystem but also cause serious economic losses, the lagoon being the second largest producer of clams in Italy. The present work aims at using a fate model coupled with COHERENS 3D hydrodynamic model to simulate and to explain the spatial distribution and temporal variations of s-triazines herbicides in the Sacca di Goro lagoon. The simulation results of spatial and temporal dynamic behaviour of atrazine, simazine and terbuthylazine have been compared with experimental data obtained during an annual monitoring programme.