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Performance Evaluation of Multi-Agent Debris Monitoring Using Parametrized Relative Motion Guidance
No full textOn-orbit inspection is a critical task for on-orbit servicing (OOS) and space situational
awareness (SSA), ensuring the health and safety of satellites and space assets. Employing
multiple agents for such tasks enhances fault tolerance and coverage, thus enabling more
efficient operations. However, implementing real-time on-orbit algorithms presents significant
challenges due to the computational complexity of optimization-based methods. This paper
presents a detailed performance analysis of a clustering-based decentralized algorithm designed
to address these challenges by simplifying the inspection process and reducing computational
demands. The algorithm is tested in more realistic dynamical scenarios, including a target orbit
with non-zero eccentricity and the presence of perturbative forces which are neglected in the
nominal model. A performance evaluation across these scenarios is conducted
Metabarcoding-based authentication of ethnic foods in the context of official control activities in Italy
No full textEthnic foods, increasingly consumed in Italy, often raise concerns regarding labelling compliance and traceability. A total of 62 pre-packed ethnic products (PPs), collected in the Latium and Tuscany regions in the context of official control activities and analysed by the Competent Authority using a validated and accredited method (DNA microarray), was re-analysed using a metabarcoding approach based on Next Generation Sequencing (NGS) technologies. The PPs included animal-based PPs (n = 37) and plant-based PPs (n = 25). Two primer pairs targeting the 16S rRNA region were selected after evaluating their taxonomic coverage based on literature data. A mislabelling rate (only assessed qualitatively) of 78.4 % was observed among animal-based PPs, with discrepancies due to undeclared species (MIS-A), missing declared species (MIS-B), or both, while DNA belonging to animal species was found in all plant-based PPs (100 %) (MIS-A). Notably, undeclared allergenic species were detected, namely fish in 18 PPs (29.0 %) and molluscs (squid or scallop) in 10 PPs (16.1 %). Although the results do not constitute official control data, they demonstrate the value of metabarcoding in strengthening surveillance efforts, particularly for the screening of complex food products. Integrating advanced molecular techniques, into official control frameworks could substantially enhance monitoring capacities, enabling more effective risk assessment and fraud prevention
Targeting Class I Histone Deacetylases Triggers Antitumor Responses in Colorectal Cancer In Vitro and In Vivo
No full textClass I histone deacetylases (HDACs) are frequently overexpressed in colorectal cancer (CRC). Combining computational, synthetic, and biological efforts, we developed novel o-aminobenzamide-based HDAC inhibitors (HDACis) optimized for class I enzyme-specific targeting. Compounds 5d and 5i emerged as lead candidates, showing strong antiproliferative effects in CRC cells with low toxicity in healthy colon epithelium. Both compounds disrupted the G2/M checkpoint through distinct mechanisms. 5i, although less potent (HDAC1 IC50 = 1508 nM), retained selectivity, upregulated p21, and triggered pronounced apoptosis. 5d (Colrestat), one of the most selective class I HDACis to date (HDAC1 IC50 = 41.2 nM, HDAC2 IC50 = 52.5 nM, and HDAC3 IC50 = 74.3 nM), induced H3K9 acetylation, p21 upregulation, and G2/M arrest. The short-term in vitro effects of 5d were modulated by a compensatory upregulation of autophagy. However, in long-term, this protective mechanism becomes insufficient to sustain tumor survival, resulting in strong antitumor efficacy in vivo in the CAM assay for both compounds even outperforming entinostat
Next-generation automotive materials: Performance-driven yucca fiber reinforced PA11 bio-composites
No full text: Developing sustainable engineering materials requires systems that merge renewable origin, mechanical resilience, thermal stability, and industrial scalability. In this study, bio-based polyamide 11 (PA11) was reinforced with yucca fibers extracted via two eco-designed routes, traditional (YT) and water retting (YWR), to create next-generation bio-composites processed through injection molding. The incorporation of yucca fibers significantly enhanced the mechanical properties of PA11. Traditionally extracted fiber-reinforced composite (PA11-YT5) enhanced tensile (35.02 MPa) and flexural strengths (43.08 MPa) compared to 34.83 MPa and 41.81 MPa for neat PA11. Meanwhile, the water-retted composites (PA11-YWR5) exhibited accepted strength (34.75 MPa in tensile, and 41.84 MPa in flexural) with greater impact resistance and improved thermal stability. Enhancing the Heat Deflection Temperature (HDT) is key for enabling bio-composites to operate in thermally demanding applications. Here, yucca reinforcement markedly improved thermal resistance: the neat matrix showed an HDT of 72.25 °C, while fiber incorporation increased it by +52% (PA11-YT5%) and + 55% (PA11-YWR5%). After hygrothermal aging (37 °C, 85% RH, 30 days), both systems retained over 98% of their initial strength in tensile, demonstrating high environmental durability. Life cycle assessment (i.e., LCA) confirmed a lower carbon footprint (≈1.27 kg CO2 eq./kg) and reduced processing energy relative to neat PA11. The results of this study highlight yucca fibers as a compelling renewable alternative to widely used natural fibers, providing consistent mechanical reinforcement and notable thermal stability. Combined with their environmental advantages, these characteristics position yucca fibers as attractive candidates for sustainable automotive components and lightweight structural applications
Risk-Aware Routing for a Robot in a Shared Dynamic Environment
No full textThis paper explores the challenge of optimal routing for a mobile robot navigating a dynamic and shared human environment. The primary goal is to minimize the risk of performance degradation during motion, such as delays in completing tasks due to the need for safe or acceptable human robot encounters. The problem is formulated as a graph whose edge costs become progressively known only as the robot moves through the environment. We model this problem as a Markov Decision Process (MDP), enabling an offline evaluation of the expected cost of alternative routes based on statistical information about human spatial distributions and possible observations at each intersection. This compact state representation scales linearly with the number of intersections in the map. Since the memoryless property of the MDP may induce loops during online execution, we compute an offline policy and introduce an online policy adaptation mechanism to prevent cyclic behaviors. Exten sive simulations across environments of different complexity, and using data collected from real-world experiments, demonstrate that our approach outperforms reactive and advanced state-of the-art planners in terms of either performance or scalability
Critical approaches to conspiracy theories in the EAL classroom Deconstructing the great replacement theory
No full textIn recent years, disinformation, fake news, and conspiracy theories have challenged the development of a healthy approach to understanding news and information in the public sphere. In particular, conspiracy theories circulating on social media and in political discourse consist of false or deceptive information, camouflaged as true facts, which is disseminated with socially disruptive aims. Like all disinformation, conspiracy theorists manipulate facts through a series of complex discursive strategies, urging a critical approach to their construal, not only for native speakers of English, but even more crucially for students of English as an additional language (EAL). This chapter responds to the call for post-truth pedagogies by reporting on research carried out on a class of EAL postgraduates in the Department of Political Science at the University of Pisa. Following the theoretical and didactic approach to Critical Literacy, students were introduced to a critical discourse analysis toolkit, with which they were subsequently asked to carry out a guided written task examining the discursive strategies employed in an online news text that supported the Great Replacement conspiracy theory. The results showed that students were able to identify a number of manipulative discourse strategies found in the text and could critically assess them in the wider socio-political context of current debates on immigration
Fatigue life prediction of multi jet fusion-manufactured polyamide12 lattice structures using the average strain energy density method
No full textThe industrial sector continues to explore innovative strategies to exploit the full potential of Additive Manufacturing (AM). Among its many advantages, AM enables the fabrication of lattice structures; these are lightweight metamaterials with tunable mechanical properties and excellent energy absorption capabilities. Despite their promise, the widespread industrial use of such structures is limited by the difficulty in accurately assessing their fatigue behavior. This study presents a methodology aimed at predicting the fatigue life of polymer-based lattice components, with a specific focus on PA12 manufactured using the Multi Jet Fusion (MJF) process. This is an industrially relevant technology offering large production volumes, high printing quality and low production costs. The approach begins with fatigue testing of bulk PA12 specimens to establish baseline material behavior. Based on these results, a predictive algorithm is developed to estimate the fatigue performance of lattice structures. The model adopts an energy-based framework inspired by the Average Strain Energy Density (ASED) method, previously used for metallic materials, and adapts it to the characteristics of polymer lattices. The proposed methodology contributes to the development of efficient fatigue assessment tools, supporting the broader adoption of lattice structures in cost-sensitive industrial applications where polymer-based materials are effective
Living in a karstic spring: humans, animals, and sediments at Zala Cave (northern-central Croatia) during the Late Glacial and Early Holocene
No full textThis study presents a geoarchaeological investigation of Zala Cave, located in northwestern Croatia, a site of exceptional significance due to its position in a key geographical corridor between the Adriatic coast and the continental Balkans, a region largely lacking comparable sequences. The cave provides rare evidence of human occupation spanning from the Late Upper Palaeolithic through the Middle Ages. Geoarchaeological, sedimentological, and micromorphological analyses of the cave deposits elucidate the interplay between human occupation, sedimentary processes, and environmental change in a karstic landscape strongly influenced by subterranean hydrology. The stratigraphic sequence documents alternating phases of fluvial sedimentation, frost-related reworking, and human use of the cave. The mineral composition of the deposits, dominated by siliciclastic grains derived from distant Triassic formations and possibly reworked loess, confirms the cave's hydrological connection to external catchments. Sediment architecture reveals periodic flooding from the underground Đulin Ponor–Medvedica–Izvor-Špilja Gojak cave system, which repeatedly transformed the cave into a spring outlet. Periodical erosion and redeposition of sediments generated gaps and mixed layers within the cultural succession, and disrupted the stratigraphic continuity. Epigravettian layers reveal short-term occupation episodes by Late Upper Palaeolithic foragers, while an in situ Mesolithic hearth attests to later visits during more temperate conditions. Sporadic Copper and Bronze Age activity reflects shifting land-use strategies, mostly pastoral. The absence of Neolithic layers and remains hints to possible erosional removal of the Neolithic horizon. Micromorphological evidence of periglacial structures, combustion features, and dung accumulations, demonstrates subsequent and/or alternating phases of cold-climate sedimentation, dwelling, and pastoral use. Overall, Zala Cave represents a key inland node linking the Adriatic and continental Balkans, offering new insights into human mobility, environmental adaptation, and the geomorphic evolution of a karstic corridor during Late Pleistocene–Holocene climatic transitions
Overall water effectiveness: A new lean indicator for digital evaluation of water efficiency in industrial processes
No full textWater management is becoming an increasingly critical challenge for manufacturing industries due to growing environmental concerns, stricter regulatory requirements, and rising pressure from clients demanding more sustainable practices. Efficient and transparent use of water resources is no longer optional but a strategic necessity across industrial sectors. In this paper a new Lean performance indicator for evaluating water usage in industrial processes is presented. The proposed indicator, named Overall Water Effectiveness, aims to systematically assess industrial water performance by quantifying the gap between actual and ideal performance. It builds on the logic of Overall Equipment Effectiveness to identify water-related losses and support informed decision-making for continuous improvement while introducing a comprehensive industrial loss structure specifically designed for water use and consumption. Jointly, two key additional indicators are introduced: one measures how effectively the production process consumes input water, while the other evaluates the dependency on external water sources, taking into account the contributions of recycled and returned water. By translating high-level sustainability goals into actionable operational metrics, this new set of indicators enables the integration of water management into daily industrial operations through a practical, easy-to-use tool. The approach is applied in a major textile manufacturing company, demonstrating its practical utility in evaluating water use and consumption, identifying loss patterns, and leading the identification of improvement actions
Combinatorial Synthesis of Protein–Polymer Conjugates by Postpolymerization Modification of Poly(pentafluorophenyl acrylate)s
No full textCombinatorial methods for preparing polymeric biomaterials enable the rapid identification of materials useful for many applications in science, medicine, and engineering. In the work described here, we demonstrate that side-chain reactive polymers can be used as templates for the rapid preparation of a small library of diversely functionalized protein-polymer conjugates. The activated ester polymer poly(pentafluorophenyl acrylate) (PPFPA) was modified postpolymerization with substoichiometric equivalents of three hydrophilic primary amines to yield a library of amphiphilic, side-chain reactive copolymers. These copolymers were then conjugated to two receptor-targeting proteins, holotransferrin (hTF) and an engineered fibronectin-based protein (Fn3), through amine-activated ester coupling. We investigated the influence of polymer:protein ratio, side-chain chemistry (i.e., hydrophilic group identity and number of protein-reactive groups), and protein identity on conjugation efficiencies. Our results demonstrate that, for polymers of similar solubility in aqueous media, a larger polymer:protein ratio yields higher conjugation efficiencies. In addition, polymers with a greater number of reactive groups or shorter hydrophilic side chains improve protein conjugation efficiency. Finally, smaller proteins couple to the polymers more efficiently than do larger proteins. Collectively, the results described here demonstrate a modular approach for efficiently preparing bioconjugates with diverse chemistries that may be of interest in a broad range of applications