This paper investigates, in a centralized manner, the motion planning problem for a team of unicycle-like mobile robots in a known environment. In particular, a multi-agent collision-free patrolling and formation control algorithm is presented, which combines outcomes of: (i) stability analysis of hybrid systems, (ii) algebraic geometry, and (iii) classical potential functions. The objective is achieved by designing a Lyapunov-based hybrid strategy that autonomously selects the navigation parameters. Tools borrowed from algebraic geometry are adopted to construct Lyapunov functions that guarantee the convergence to the desired formation and path, while classical potential functions are exploited to avoid collisions among agents and the fixed obstacles within the environment. The proposed navigation algorithm is tested in simulation and then validated by using the robots of a remote accessible robotic testbed.
The sluggish kinetics associated with the oxygen evolution reaction (OER) limits the sustainability of fuel production and chemical synthesis. Developing catalysts based on Earth abundant elements with a reasonable strategy could solve the challenge. Here, we present a heterostructure built from CrOx and CuS whose interface gives rise to the advent of new functionalities in catalytic activity. Using X-ray photoelectron and absorption spectroscopies, we identified the multiple oxidation states and low coordination number of Cr metal in CrOx-CuS heterostructure. Benefitting from these features, CrOx-CuS generates oxygen gas through water splitting with a low over potential of 190 mV vs RHE at a current density of 10 mA cm⁻². The catalyst shows no evident deactivation after a 36-hours operation in alkaline medium. The high catalytic activity, inspired by first principles calculations, and long-time durability make it one of the most effective OER electrocatalysts.
In view of increasing global population, expected to reach 10 billion by 2050 and of the deriving shortage of natural resources, there is an urgent need to improve food production. Until a few years ago breeding has been limited to a low number of vegetal species, and agronomic technology has been directed mainly to achieve higher production yield and excellent postharvest quality. Nowadays, the increasing awareness of the necessity of a shift to sustainable productions is focusing the attention of researchers to other features (e.g., novel plant sources, drought tolerance, nutrient use efficiency, durable pest and disease resistance, environmental outcomes), all factors now recognized as greatly affecting the biodiversity and the sustainability of food productions. The goal of global food security will be achieved only by improving the qualitative and quantitative traits of crops through exploitation of metabolic pathways involving advanced analytical tools and technologies. This book comprehensively reviews the application of various aspects of rapidly growing omics technologies - including genomics, epigenomics, proteomics, and metabolomics for crop development.
Structural Health Monitoring (SHM) is gaining increasing attention in Italy and worldwide due to structural obsolescence and sudden collapses occurring from time to time due to insufficient maintenance or extreme events. On the other hand, the technological progress in the SHM field is making it particularly attractive as a complement to visual inspections and in-situ surveys aimed at assessing the structural safety. Accordingly, several guidelines have been developed with the aim to provide useful recommendations to technician for the design of SHM systems. Nevertheless, because of very case-specific design, so far, a general qualification procedure aimed at assessing the performance of a SHM system is still missing. On the contrary, construction products already share a thorough and well-established harmonized standardization framework since many years, and this resulted in a reliable control of performance. In this study, a preliminary qualification approach for SHM systems is proposed. The qualification scheme is scenario dependent and allows to check the effectiveness of a given SHM system defined in terms of hardware as well as software components. In order to validate the approach, different SHM systems are hypothesized and checked for possible qualification with respect to different scenarios, obtaining encouraging results. The proposed approach, therefore, represents a promising attempt towards a more exhaustive and comprehensive qualification framework for civil SHM applications.
The management process and safety evaluation of existing buildings, which have often overcome their service life, can be properly supported by non-invasive structural monitoring techniques, among which multi-temporal Differential Synthetic Aperture Radar Interferometry (MT-DInSAR) techniques can be included. The paper follows previous works of some of the authors on this topic, giving an insight on the proper use, processing and interpretation of satellite radar interferometry data for the structural analysis, through an application to the “Vittorino da Feltre” school building located in the city centre of Rome (Italy), within the framework of a retrofitting project. After performing a correct positioning of the reflecting targets on the 3D geometry of the structure under investigation, displacement time series, mean deformation velocity values and continuous maps of the vertical and East-West velocity components are presented, by exploiting the COSMO-SkyMed SAR data collected during the 2011–2019 time interval. Finally, a comparison of the obtained results with the on-site detected cracking pattern can be useful to better understand the ongoing phenomena, for a proper damage assessment.
A recently optimized rapid, cheap, and accurate coulometric method has been exploited to determine the antioxidant capacity of bergamot (Citrus bergamia Risso) by-products, including first (FPJ) and second press juices (SPJ), in comparison to analogous products from several citrus species. Extracts from the entire edible part (i.e., juice and pulp) and de-oiled peel of bergamot were also assayed. The Coulometrically Determined Antioxidant Capacity (CDAC) data, expressed as moles of electrons per mass of sample, were evaluated with other parameters such as total phenolic compounds, ascorbic acid, total carotenoids, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical inhibition. The CDAC of bergamot FPJ (39 mmol e⁻ kg⁻¹) was comparable with other citrus juices (20–65 mmol e⁻ kg⁻¹ range), whereas the CDAC of bergamot SPJ (816 mmol e⁻ kg⁻¹) was strikingly higher than the counterparts from other citrus fruits. This value approached that of bergamot peel extracts (822 mmol e⁻ kg⁻¹). Bergamot peel and SPJ also exhibited the highest DPPH inhibition. The CDAC values were associated with the HPLC-determined content of flavonoids, namely neoeriocitrin, naringin, and neohesperidin, which were 4-10-fold more concentrated in bergamot SPJ and peel than in SPJ from other citrus species. These findings contribute to point at bergamot by-products as rich sources of antioxidant compounds on a quantitative basis, highlighting their enormous potential for pharmaceutical, nutraceutical and food applications.
This article presents the structure and results of a simplified model (VISTOCK) for simulating grass growth and water dynamics of grassland systems. The model, based on a process-based approach coupled with proximal (SKR 1800 2-Channel Light Sensor) and remote (Sentinel-2) NDVI-derived data for estimating LAI, simulates aboveground biomass (AGB), net primary production (NPP), evapotranspiration (ET), and the fraction of transpirable water in soil (FTSW). VISTOCK simulated a grassland system with few meteorological data (i.e., minimum and maximum daily temperatures, precipitation, global solar radiation), considering limitations to vegetation growth due to thermal and water stresses. It was calibrated for a natural alpine grassland in Italy (site T) during the most contrasting meteorological seasons of the dataset (2012, 2017, and 2018). It was then evaluated for the remaining years at site T (2013, 2014, 2015, and 2016) and for other two sites in Italy (sites B1, B2 and M) with different soil and climate conditions and diverse management strategies (2020 and 2021). VISTOCK accurately predicted AGB during the growing season (RMSE = 445, 240, 219, 365 kg DM ha⁻¹ for T, M, B1, and B2, respectively) as well as for NPP, ET, and FSTW at site T. Simulation results suggest the ability of the model to simulate grassland in diverse environments with few inputs and parameters to be calibrated. The model’s simplified structure, combined with easy-to obtain input data and easy applicability, encourages its wider use for out- and/or upscaling and decision making.
The standardization of procedures for the post-collection management of semen samples is a prerequisite for the development of husbandry techniques, as well as for the use of semen in laboratory research. Despite the relevance of the sea urchin Sphaerechinus granularis as a laboratory model, the basics related to sperm collection and storage have received little attention. The aim of this research was to optimize procedures for the management of S. granularis semen, focusing on the post-collection storage of samples. Specifically, the effects of post-collection storage conditions on sperm motility parameters were evaluated; motility was assessed by computer-assisted analysis (CASA-mot) upon activation (t0), and 15 min, 30 min and 60 min after dilution in freshly collected semen, and in chilled and cryopreserved samples. Motility parameters remained unchanged for up to 60 min after activation in both fresh and chilled semen. In cryopreserved samples, sperm motility upon activation was significantly lower than in fresh semen; however, no differences with respect to t0 values were recorded when thawed semen was cold- incubated for up to 60 min post activation, thus meeting standards required by germplasm cryobanks. Post-activation longevity showed by both fresh and stored S. granularis semen, as well as its resistance to cryopreservation, are positive spermatological features that will allow the running of easy management procedures, encouraging a wider use of S. granularis in hatchery practices, as well as in laboratory activities.
We study from first principles the magnetic, electronic, orbital and structural properties of the LaMnO3 doped with gallium replacing the Mn-site. The gallium doping reduces the Jahn–Teller effect, and consequently the bandgap. Surprisingly, the system does not go towards a metallic phase because of the Mn-bandwidth reduction. The Ga-doping tends to reduce the orbital order typical of bulk antiferromagnetic LaMnO3 and consequently weakens the antiferromagnetic phase. The Ga-doping favors the G-type orbital order and layered-ordered ferromagnetic perovskite at x=0.50, both effects contribute to the formation of the insulating ferromagnetic phase in LaMn1−xGaxO3.
This chapter illustrates the major anthropic impacts shaping the geological, biological, and biogeochemical dynamics of the Mediterranean Sea. A syntheric descriptions (i) of the main modifications of deep sea floor integrity and coastal landscapes is complemented by an in-depth picture of critical changes in the biogeochemical dynamics of major nutrients and pollutants (including a detailed paragraph on plastics) at Mediterranean scale.
This chapter starts with a brief summary of the geological processes that resulted in the formation of the Mediterranean Sea. The main content of the chapter focuses on the description of the different processes that control recent sedimentation at the seafloor in coastal areas and in the deep sea, on how submarine volcanoes are formed and evolve and how fluid escape at the seafloor form cold seeps and related deposits. Finally, the implications of all these processes for geohazards and ecosystems are discussed.
This chapter describes the tectonic processes at the origin of the Mediterranean Sea and a particular paleo-environmental event (the Messinian salinity crisis) that resulted in the almost complete desiccation of the Mediterranean Sea. It also presents the morphological characteristics of the basin floor and introduces the tectonic and climatic processes that control sedimentation and thus the evolution of the seafloor.
This chapter describes general concepts about temporal changes of water mass properties in the Mediterranean Sea, focusing in particular on the second half of 20th century and the beginning of the 21st century. The changes (both gradual and abrupt) that have been observed over the past decades in the Eastern and in the Western Mediterranean Sea are examined, putting them in relation to what is happening in the Atlantic Ocean. The description is done in the context of global changes occurring in the oceans.
Sustained observations and forecasting systems are fundamental to advance our knowledge and understanding of the functioning of the Mediterranean Sea and its ecosystems, and to efficiently respond to maritime emergencies, societal needs, and preservation threats. This chapter describes the present status of the Mediterranean observing and forecasting systems that were successfully developed over the recent decades, thanks to both national and regional investments and fruitful international collaborations. On the one hand, the complementarity between global observing systems and multiplatform regional observatories enables a systematic monitoring of the Mediterranean Sea from the basin to the coastal scales. On the other hand, operational high-resolution modeling combined with data assimilation procedures provide the base for integrated model-data forecasting systems generating timely predictions of the short-term evolution of marine conditions and realistic representations of past periods. Data assembly centers are essential backbone of these systems, allowing data standardization, quality control, distribution, and archiving.
This chapter aims at introducing the reader to general concepts about the main forcings of the Mediterranean Sea, in terms of exchanges through the Strait of Gibraltar, and air-sea exchanges of heat, freshwater, and momentum. These forcings are also responsible for the peculiar characteristics of Mediterranean water masses. Therefore, the chapter continues with giving a general explanation on water mass analysis, and then it describes the properties and vertical and horizontal distributions of the main Mediterranean water masses. To conclude, the reader is introduced to the use of other (biogeochemical, and chemical) tracers of water masses, with a focus on the Mediterranean Sea.
This chapter gives an overview of the general biogeochemistry in the Mediterranean Sea explaining the particularities of the main biogeochemical variables and the physical, biological, and geochemical processes driving their distribution in the main basins of this marginal sea. Each subsection focuses on one essential variable, starting from dissolved oxygen and following inorganic nutrients, dissolved organic carbon and the CO2 system. A brief overview on the utility of those biogeochemical variables to identify water masses is also given. The chapter concludes with a summary of the projections and threats on biogeochemistry in the Mediterranean Sea under different future climate change scenarios.
The computational power available nowadays to industry and research paves the way to increasingly more accurate systems for the wind resource prediction. A promising approach is to support the mesoscale numerical weather prediction (NWP) with high fidelity computational fluid dynamics (CFD). This approach aims at increasing the spatial resolution of the wind prediction by not only accounting for the complex and multiphysics aspects of the atmosphere over a large geographical region, but also including the effects of the fine scale turbulence and the interaction of the wind flow with the sea surface. In this work, we test a set of model setups for both the mesoscale (NWP) and local scale (CFD) simulations employed in a multi-scale modelling framework. The method comprises a one-way coupling interface to define boundary conditions for the local scale simulation (based on the Reynolds Averaged Navier–Stokes equations) using the mesoscale wind given by the NWP system. The wind prediction in an offshore site is compared with LiDAR measurements, testing a set of mesoscale planetary boundary layer schemes, and different model choices for the local scale simulation, which include steady and unsteady approaches for simulation and boundary conditions, different turbulence closure constants, and the effect of the wave motion of the sea surface. The resulting wind is then used for the simulation of a large wind turbine, showing how a realistic wind profile and an ideal exponential law profile lead to different predictions of wind turbine rotor performance and loads.
In the western Mediterranean, following the intervening continent-continent collision, the subduction of the Tethyan ocean has progressively come to an end or almost in large sectors. Compressional deformation connected with the ongoing Africa–Eurasia convergence has therefore progressively resumed mostly along the southern passive margins of the Mediterranean back-arc basins. The aim of this paper is to trace this nascent boundary and constrain its kinematics through geodetic and seismological data recorded between the Ionian Sea and Gulf of Cadiz, and through pre-existing tectonic data. Based on these data, the nascent plate boundary is drawn, kinematically defined, and compared with the previously identified boundaries in the same region. The nascent boundary is weaving and formed by variably oriented inherited structures. It is characterized by a discrepancy between the general motion of Africa with respect to Eurasia and the local contractional/compressive axes deduced from geodetic and seismic data. The oblique convergence along the nascent boundary matches that recorded in other instances of subduction initiation elsewhere; however, the average convergence rate (∼5mm/yr) in the Mediterranean seems currently too small for such a subduction initiation. Based on the assumption of a future northward tectonic vergence (i.e., Eurasian foreland), the Tyrrhenian, Algerian, and Betic salients, the Oran and Fès recesses, and the Ionian, Trans-Alboran, and Gibraltar transfer zones are identified along the nascent boundary. The latter zones connect salients and recesses through strike-slip displacements. The Algerian offshore hosts a long segment of the boundary characterized by locally increased seismic rate and actual northward vergence that would suggest this area being the first nucleus of subduction initiation in the western Mediterranean, as was previously proposed.
Social dilemmas play an important role in the study of cooperative behaviours. In this experiment we tested the strategies adopted by tufted capuchin monkeys, Sapajus spp., when faced with a cooperative situation involving a conflict of interest, simulating a Snowdrift game. We tested 12 capuchin monkeys (six dyads) in two experimental conditions: Snowdrift (cooperation) and Competition. Monkeys had the opportunity to pull a string to move a rotating bar and obtain a reward while delivering a different reward to their partner. Pulling in the Snowdrift condition delivered a smaller reward to the individual pulling the string and a larger reward to the partner, while the opposite happened in the Competition condition. If neither monkey pulled within 30 s, neither received a reward. Monkeys were also individually tested in a battery of self-control tasks. Capuchin monkeys successfully coordinated (i.e. obtained a reward) in 100% of trials and flexibly adapted their behaviour to the different experimental conditions, by pulling earlier in the Competition and later in the Snowdrift condition. Dominance rank and self-control had no effect on the latencies to pull in either experimental condition. No evidence of any alternation strategy was observed. Our results suggest that capuchin monkeys can solve a conflict of interest without engaging in complex calculations.
The styrene oxide to styrene carbonate conversion performed in CO2 atmosphere, herein selected as a case study, was implemented in microdroplets (aerosol) reactions at the preparative scale (3.5 mmol of the starting material) and mild conditions (1 atm CO2 pressure), within a custom-made ultrasonic nebulization reactor. Upon optimization of the promoter stoichiometry (1 eq of 4.3 TEG/KI ratio) and methanol (MeOH) dilution (7.5 mL of 2.5 v/v MeOH/TEG), performances under mass transfer-limited conditions of this novel methodological paradigm have been compared at 25 °C and 50 °C with those implemented as: a) no-stirred, b) stirred, and c) sonicated bulk reactions. Complete selectivity and an apparent acceleration factor (AAF) of 1.9 was registered at both temperature for microdroplets reactions in respect with the sonicated counterparts, these latter performing better than the other bulk reactions. These significative efficiency improvements, candidate aerosol reactions as a preferred process intensification approach in the realm of effective CO2-utilization strategies and, in general, in the development and exploitation of gas-liquid two-phase reactions.
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