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Freshwater mussels (FM) are suitable biological indicators to assess environmental stressors. Behaviour is a good parameter to measure rapid mussel’s responses. In this sense, valvometric method, that exploits the Hall sensor (real-time remote monitoring tool), has been used to measure the behavioural responses of mussels (valve opening amplitude and valve opening-closure frequency). During the last two decades, these methodologies have been used to measure the presence of the pollutants in the waterbodies. However, studies that focus on physical disturbances in the environment related to climate changes are lacking. Since future climatic scenarios in Europe predict an increase in temperature and change in the hydrological conditions, the main objective of this study was to evaluate the influence of water temperature increase and water discharge rates (without and with sediment transport) in four endpoints of mussel's behaviour: normal activity, resting, transition and avoidance. Our results suggest, that on experiments with increasing temperatures and high variation in water discharge rates with sediment transport, mussels presented high valve opening-closure frequencies and amplitudes. In this sense, mussels could be used as biological sensors to monitor changes in thermal and hydrological conditions which are increasing with climate changes.

Freshwater mussels are considered suitable bioindicators and used in real-time remote monitoring systems to detecting disturbances on ecosystems. One of the most successful methods is the valvometric technique that exploits the Hall sensor to measure the valve gaping behavior of mussels. The duration and frequency of valve opening amplitude and closure can therefore be recorded. These technologies have been used in the past to detect pollutants in the water, whereas studies that address the impact of hydromorphological pressures are still lacking. The main aim of the present study is to assess the influence of flow with sediment transport as well, both in steady and in unsteady (transient) conditions, in four endpoints of mussel's behavior: normal activity, resting, transition and avoidance. To this aim, experiments in laboratory flumes with mussels on a bed made of sands, for varying flow discharges, have been conducted. Results suggest that during transients and in the presence of sediment transport, mussels change their behavior, showing an increase of their valve opening-closure frequencies and amplitudes. These results are encouraging to support the use of mussels as biosensor also in their natural habitat (rivers or lakes) to monitor the occurrences of natural events involving hydro-morphological variations, as floods.

In the present essay I would like to explore the different meanings of the emotion named Schadenfreude from a perspective integrating Plato’s and Aristotle’s moral philosophy with the analyses of phenomenological anthropologists such as Scheler, Plessner and Blumenberg. In the first half of my essay I will focus on Aristotle’s distinction between, on the one hand, a pleasure at another’s misfortune which does not necessarily obstruct pity in the opposite position and provides relief from indignation, and a malicious pleasure at another’s misfortune (epichairekakia) understood as the opposite of envy. In the second half of the essay I will examine the link between the joy involved in Schadenfreude and laughter by asking whether and to what extent this contemplative emotion contributes to the emergence of a theoretical attitude.

The complex aquatic ecosystems, such as lakes, are generally characterized by a high degree of spatial and temporal changes. In particular, hourly and daily dynamics are evident due, for examples, to the growth/decrease of phytoplankton depending on light availability and to the variation of the suspended solids in wind-induced resuspension of the bottom sediments. Such a variability is then changing depending on location, so that variation in spatial patterns is also a typical feature of these ecosystems. Satellite images have been used widely since many decades to observe and to understand spatial and temporal variability of water constituents, while the exploration of hourly temporal variability is still limited to geostationary sensors, whose spectral and spatial resolutions are anyway limited for resolving the optically complexity of inland waters. To fill this gap, in this contribution we present the results obtained by acquiring Remote Sensing Reflectance (Rrs) from two hyperspectral spectroradiometers mounted on fixed platforms and / or on floating buoys. These sensors allow to gather continuous measurements during the day and for several consecutive days from two different yet comparable devices. A set of Rrs measures were taken by a WispStation (manufactured by Water Insight) in Lake Trasimeno (in the April-September 2018 range). The system measures every 10 minutes the radiance and irradiance in the spectral range of 350-900 nm with a spectral resolution of 3 nm. The set-up is based on an automatic system so that the instrument detect the water surface at optimal azimuth angles for most of the day. A second set of Rrs spectra was instead acquired by a ROX sensor (manufactured by JB Hyperspectral devices) operated on a floating buoy in Lake Maggiore at the end of June 2018. The ROX system is assembling Ocean Optics spectroradiometers and it operates in the range 400-950 nm with a spectral resolution of 1.5 nm and with an acquisition time of 1 minute. The analysis aims to adapt the state-of-the art algorithms for retrieving biogeochemical parameters to the next generation of hyperspectral satellite (apart a continuous testing with OLCI).