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Abstract: An evaluation of the performance of artificial neural networks (ANNs) to forecast monthly anchovy (Engraulis ringens) and sardine (Sardinops sagax) catches in northern Chile (18°21′S-24°S) is presented, using environmental variables, anchovy and sardine CPUE, fishing effort and catches between 1963 and 2007. An analysis of previous data was carried out, consisting of a non-linear cross-correlation analysis to estimate the time lags for each input variable. A multi-layer perceptron architecture model was used, calibrated with the Levenberg–Marquardt algorithm, thus obtaining anchovy landings and sardine CPUE forecast models. An ecosystemic approach was conducted for both models, considering local and global environmental variables, the anthropogenic effect, and the interaction between species as inputs. The variance explained by both models was slightly higher than 82% and the standard error of prediction was lower than 45%. The strong correlation between the estimated and observed series on the anchovy and sardine models suggests that ANN models capture the trend of the historical data. Furthermore, the generalization capacity along with the sensitivity analysis allowed the identification of high-weight variables in the model, as well as the partial interpretation of the statistical functional relationships between the input variables and the abundance. [ABSTRACT FROM AUTHOR]

Beta-trace protein (BTP) is a low–molecular mass protein belonging to the lipocalin protein family, which is more sensitive than serum creatinine for detecting impaired renal function. The aims of the present study were to evaluate whether plasma BTP improves the risk stratification of patients with non–ST-segment elevation acute coronary syndromes and to compare it to cystatin C (CysC), serum creatinine, and estimated glomerular filtration rate. Two hundred twenty-six consecutive patients with non–ST-segment elevation acute coronary syndromes were prospectively included. Blood samples were obtained within 24 hours of hospital admission to measure BTP, CysC, and creatinine. The study end point was all-cause death. Over a median follow-up period of 859 days (interquartile range [IQR] 524 to 1,164), 24 patients (10.6%) died. Decedents had higher concentrations of BTP (1.03 mg/L [IQR 0.89 to 1.43] vs 0.74 mg/L [IQR 0.61 to 0.92], p <0.001), CysC (1.16 mg/L [IQR 0.91 to 1.59] vs 0.90 mg/L [IQR 0.76 to 1.08], p = 0.001), and serum creatinine (1.10 mg/L [IQR 0.87 to 1.46] vs 0.94 mg/L [IQR 0.80 to 1.10], p = 0.004) and a lower mean estimated glomerular filtration rate (60 ± 20 vs 80 ± 24 ml/min/1.73 m2, p <0.001). After multivariate adjustment, BTP and CysC were predictors of all-cause death, while estimated glomerular filtration rate and serum creatinine concentrations did not achieve statistical significance. In stratified analyses according to kidney function, elevated BTP and CysC were associated with a higher risk for all-cause death. Reclassification analyses showed that BTP and CysC added complementary information to Global Registry for Acute Coronary Events (GRACE) risk score. In conclusion, BTP and CysC levels were associated with all-cause death risk and modestly improved prognostic discrimination beyond the GRACE risk score in patients with non–ST segment elevation acute coronary syndromes. [ABSTRACT FROM AUTHOR]

Abstract: The effect of daily intakes of two differently processed fruit and vegetable soups on β-carotene and lycopene bioavailability, oxidative stress and cardiovascular risk biomarkers was investigated. An optimised soup produced using heat treatments and high pressure homogenisation for high nutrient retention, and a traditionally produced reference soup were tested. Serum β-carotene concentration was significantly higher with the optimised than with the reference soup after the supplementation (0.41±0.05 vs. 0.24±0.03μM, respectively), whereas the serum lycopene concentration was higher in subjects consuming the reference (0.06±0.02 vs. 0.16±0.02μM). The change in serum homocysteine levels tended to be greater in the optimised group (−1.67±0.63 vs. 0.02±0.17μM, p =0.06). Serum antioxidant enzyme activity decreased significantly with consumption of both soups, but to a greater extent with the optimised soup. The consumption of the fruit and vegetable soups increased serum β-carotene and lycopene concentrations and reduced the levels of several oxidative stress makers, particularly in subjects consuming the optimised soup. [Copyright &y& Elsevier]

Abstract: In this study the performances of computational neural networks (CNNs), multiple linear regressions (MLRs) and generalised additive models (GAMs) to predict Pacific sardine (Sardinops sagax) landings and to analyse their relationships with environmental factors in the north area off Chile were studied. For this purpose several local and global environmental variables and indexes (sea surface temperature, sea level and Ekman transport index in the Chilean coast and, sea surface temperature in the area Niño 3+4 and Niño 1+2, and the south oscillation index) were considered as inputs or independent variables. Additionally, several CNNs were calibrated and validated adding the anchovy (Engraulis ringens) landings in the same area as model inputs. The time lags of the variables considered were selected through analysis of the non-linear cross-correlation functions and an alternative form of sensitivity analysis based on the approach of the missing value problem. The analysis of error measures with validation data set showed that the best results were obtained when local and global variables were used separately and combined with anchovy landings. Globally, the best result was given by a CNN with 18 input variables (model CNN 6(II) which only considered global variables and anchovy landings) and 10 neurons in a hidden layer. For this configuration the explained variance was slightly higher to 86% which supposed a standard error of prediction of 7.66%. These results were significantly better than those obtained with MLRs and GAMs. The strong correlation between predicted and observed sardine landings suggests that CNNs captured the trend of the historical data. Also, the generalisation capacity together the sensitivity analysis allowed us to identify the variables with a high weight in the model and partially to interpret the statistical functional relationships between these environmental variables and sardine landings. [Copyright &y& Elsevier]

Investigates the current meter observation of the exchanged flows at the Strait of Gibraltar within Canary Islands Azores Gibraltar Observations project. Characteristic of the water inflow; Predominance of semiannual signals at the outflow and the depth of the interface; Analysis on the semiannual cycle.