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The epode of Archilochus (s. vii B. C.) composed by the ff. 172-181 S. offers a reading of the poem where the αἶνος of the eagle and the fox is presented as an exemplum of events narrated within the biographical tradition of the poet. This paper aims, on the one hand, to research how elements such as friendship, betrayal and revenge links both narratives; and, on the other hand, it intends to examine the interaction between the fable and the iambus. The analysis concludes that, in this epode, the violation of the codes of "commensality" plays a very important role in the interrelation between iambus, fable and biographical tradition. [ABSTRACT FROM AUTHOR]

This paper presents a fault detection system for photovoltaic standalone applications based on Gaussian Process Regression (GPR). The installation is a communication repeater from the Confederación Hidrográfica del Ebro (CHE), public institution which manages the hydrographic system of Aragón, Spain. Therefore, fault-tolerance is a mandatory requirement, complex to fulfill since it depends on the meteorology, the state of the batteries and the power demand. To solve it, we propose an online voltage prediction solution where GPR is applied in a real and large dataset of two years to predict the behavior of the installation up to 48 hour. The dataset captures electrical and thermal measures of the lead-acid batteries which sustain the installation. In particular, the crucial aspect to avoid failures is to determine the voltage at the end of the night, so different GPR methods are studied. Firstly, the photovoltaic standalone installation is described, along with the dataset. Then, there is an overview of GPR, emphasizing in the key aspects to deal with real and large datasets. Besides, three online recursive multistep GPR model alternatives are tailored, justifying the selection of the hyperparameters: Regular GPR, Sparse GPR and Multiple Experts (ME) GPR. An exhaustive assessment is performed, validating the results with those obtained by Long Short-Term Memory (LSTM) and Nonlinear Autoregressive Exogenous Model (NARX) networks. A maximum error of 127 mV and 308 mV at the end of the night with Sparse and ME, respectively, corroborates GPR as a promising tool. [ABSTRACT FROM AUTHOR]

This article describes a comprehensive testing method for the thermal calibration of the Thermal InfraRed Sensor (TIRS) onboard NASA's Perseverance rover. Ground-based IR detectors operating at the surface of Mars are subjected to inaccuracies caused by the inclusion of thermal gradients in their packages. To reduce such uncertainties, it is necessary to compensate for their effects. Here, details of the TIRS thermo-mechanical design and a simplified thermal mathematical model (TMM) that accounts for the presence of thermal gradients in the detector's package are provided. Then, a set of equations for the estimation and compensation of thermal gradients are proposed based on the results of the TMM. Thermal calibration tests to identify the mathematical estimators are analyzed, providing details of the test setups and highlighting their limitations and restrictions. Finally, experimental results of the calibration tests are presented, along with the uncertainty sources and potential systematic errors associated with the estimation of the gradients. The results presented here show a significant improvement in the accuracy of TIRS versus previous work, thus fulfilling of the radiometer scientific requirements set by the Mars 2020 science team. • A new thermal calibration plan for a ground-based Martian IR radiometer. • Detectors package thermal gradients estimation based on thermal modeling and tests. • Simplified test setups and differences with the Martian environment. • Performance analysis accounting for test setup uncertainties and thermal modeling. • Uncertainties meet the scientific requirements stated by the Mars 2020 science team. [ABSTRACT FROM AUTHOR]

The Mars Environmental Dynamics Analyzer (MEDA) is a suite of environmental sensors onboard NASA’s Mars 2020 mission. The Thermal InfraRed Sensor (TIRS), developed at Centro de Astrobiología of Spain, is one of the six sensors comprising MEDA, and it will measure the net thermal infrared radiation and reflected solar radiation at the surface, as well as the atmospheric and surface skin temperatures using five different channels. In combination with MEDA's other sensors, TIRS will allow the quantification of the surface energy budget and the determination of key geophysical properties of the terrain such as the albedo and thermal inertia. Here we present a general description of the TIRS, its channels scientific requirements, and the mechanical and thermal design. Then, a detailed sensor mathematical model and a sensitivity analysis to model uncertainties are described. Some characterization test results to model parameters identification are included. Finally, accuracy and resolution calculus for each channel versus operational temperature is presented. The calculus is performed based on sensitivity equations, the practical tests results and the estimated values for different uncertainty sources. [ABSTRACT FROM AUTHOR]

Corbicula fluminea is an aggressive invasive species that has successfully colonized aquatic habitats worldwide, producing changes in natural environments and impacting endemic populations. As disturbed environments may favor the adaptive success of exotic species over native ones, we studied the fitness response of two freshwater bivalves, invasive C. fluminea and native Diplodon delodontus, to the presence of metals in the Parana de la Palmas River. To assess the health status of both species, we analyzed morphological and histological alterations in the digestive gland and their relation to metal concentrations in this organ and in the water. Water and specimens sampling took place in the first section of the delta of the Parana River in June and September. Most metal concentrations increased in the river, although in the digestive gland only iron in D. delodontus and nickel and zinc in C. fluminea increased seasonally. Digestive gland factor and hepatosomatic index indicated higher values in C. fluminea in both periods. Despite histological analysis showing a decrease in atrophic tubules frequency in both species, which was followed by histomorphometric parameters of the epithelium and lumen of the digestive tubules, C. fluminea exhibited a greater physiological capacity for metal metabolism and recovery. These results suggest that the physiological characteristics of the Asian clam C. fluminea, combined with its reproductive efficiency and broad dispersal capacities, could explain its invasive dispersal competence over the D. delodontus in the disturbed environmental conditions observed in the Parana de las Palmas River. [ABSTRACT FROM AUTHOR]

• A new radiometric and angular calibration plan for a Martian IR radiometer. • Simplified test setups and differences with Martian environmental are described. • Spectral response analysis vs. radiation incidence angle and operational temperature. • Performance analysis accounting for calibration uncertainties and set-up limitations. • Uncertainties meet the scientific requirements stated by the Mars 2020 science team. This article describes a comprehensive testing method for the radiometric and angular calibration of the Thermal InfraRed Sensor (TIRS) onboard NASA's Mars 2020 mission. First, details of the TIRS opto-mechanical design, construction aspects of the IR detectors, and an update of the mathematical model used for the calculation of sensor internal IR fluxes are provided. Then, a set of sequential calibration tests to identify the radiometer model parameters are defined. The test setups are described, highlighting their limitations and restrictions based on differences between simulated and actual Martian environmental conditions. Finally, the uncertainty sources and potential systematic errors associated with the calibration tests are quantified and compared with the radiometer scientific requirements established by the Mars 2020 science team. [ABSTRACT FROM AUTHOR]

Axial spondyloarthritis (axSpA) comprises a spectrum of chronic inflammatory manifestations affecting the axial skeleton and represents a challenge for diagnosis and treatment. Our objective was to generate a set of evidence-based recommendations for the management of axSpA for physicians, health professionals, rheumatologists and policy decision makers in Pan American League of Associations for Rheumatology (PANLAR) countries. Grading of Recommendations, Assessment, Development and Evaluation-ADOLOPMENT methodology was used to adapt existing recommendations after performing an independent systematic search and synthesis of the literature to update the evidence. A working group consisting of rheumatologists, epidemiologists and patient representatives from countries within the Americas prioritized 13 topics relevant to the context of these countries for the management of axSpA. This Evidence-Based Guideline article reports 13 recommendations addressing therapeutic targets, the use of NSAIDs and glucocorticoids, treatment with DMARDs (including conventional synthetic, biologic and targeted synthetic DMARDs), therapeutic failure, optimization of the use of biologic DMARDs, the use of drugs for extra-musculoskeletal manifestations of axSpA, non-pharmacological interventions and the follow-up of patients with axSpA. This Evidence-Based Guideline presents the first Pan American League of Associations for Rheumatology recommendations for the management of axial spondyloarthritis, addressing therapeutic targets, the use of pharmacological and non-pharmacological interventions and monitoring of patients. [ABSTRACT FROM AUTHOR]

This research examines fired clay bricks made with waste pomace from the wine industry as an additive in brick production. To this end, we analyse and discuss the chemical, mineralogical, textural and physical-mechanical behaviour of fired bricks made with three concentrations of wine pomace (2.5, 5 and 10 wt%) and at three different firing temperatures (800, 950 and 1100 °C) and evaluate their durability to salt crystallization. Variations in colour were also examined. The firing process resulted in the decomposition of phyllosilicates and carbonates, the crystallization of Fe oxides and the appearance of high-temperature Ca- (and Mg-) silicates phases such as gehlenite, wollastonite, anorthite and diopside. The bricks made with added wine pomace had very similar mineralogy to the control samples made without it. The bricks made with added wine pomace were lighter than the control samples and underwent less linear shrinkage during the drying process. Particles in the wine pomace were consumed during firing, leading to the appearance of voids. The bricks made with this additive had higher levels of water absorption and poorer mechanical strength. The greatest colour differences were detected after increasing the amount of waste, which generally resulted in yellower bricks. The increase in firing temperature resulted in an improvement in mechanical resistance regardless of the composition of the bricks. However, bricks fired at 1100 °C made without additive are more resistant to damage caused by salts than those made with wine pomace. [Display omitted] • The reuse of wine pomace reduces the quantity of clayey material in the production of bricks. • The addition of wine pomace augments the size and number of pores in the bricks. • Bricks with wine pomace are suitable for use as lightweight materials in the construction industry. • The addition of wine pomace modifies the lightness and chromatism of bricks, not the mineralogy. [ABSTRACT FROM AUTHOR]

The article discusses that Despite the importance of sand and dust to Mars geomorphology, weather, and exploration, the processes that move sand and that raise dust to maintain Mars' ubiquitous dust haze and to produce dust storms have not been quantified as the missions lack either the necessary sensors or a sufficiently active aeolian environment.