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Vision-Aided Velocity Estimation in GNSS Degraded or Denied Environments
No full textThis paper introduces a novel architecture for a navigation system that is designed to estimate the position and velocity of a moving vehicle specifically for remote piloting scenarios where GPS availability is intermittent and can be lost for extended periods of time. The purpose of the navigation system is to keep velocity estimation as reliable as possible to allow the vehicle guidance and control systems to maintain close-to-nominal performance. The cornerstone of this system is a landmark-extraction algorithm, which identifies pertinent features within the environment. These features serve as landmarks, enabling continuous and precise adjustments to the vehicle’s estimated velocity. State estimations
are performed by a Sequential Kalman filter, which processes camera data regarding the vehicle’s relative position to the identified landmarks. Tracking the landmarks supports a state-of-the-art LiDAR odometry segment and keeps the velocity error low. During an extensive testing phase, the system’s performance was evaluated across various real word trajectories. These tests were designed to assess the system’s capability in maintaining stable velocity estimation under different conditions. The results from these evaluations indicate that the system effectively estimates velocity, demonstrating the feasibility of its application in scenarios where GPS signals are compromised or entirely absent
Chemesthetic Perception in Extra Virgin Olive Oil and Olive Ripening Stage: A Sensory Perspective
No full textThis review focuses on chemesthetic perception (i.e., pungency, tingling, and astringency) in extra virgin olive oil (EVOO), with particular attention to the sensory mechanisms underlying trigeminal stimulation elicited by phenolic secoiridoids, considering olive-fruit ripening as a key modulating factor. The chemesthetic profile represents one of the most distinctive sensory features of EVOO and is primarily associated with phenolic secoiridoids derivatives, formed through enzymatic transformations of ligstroside and oleuropein. Generally, a progressive decrease in chemesthetic potential is observed during ripening, due to the reductions in total phenols, o-diphenols, and secoiridoids. Among these compounds, secoiridoid derivatives, most notably oleocanthal and oleacin, elicit chemesthetic sensations and represent some of the most biologically active EVOO phenolic constituents. In this context, chemesthetic perception may work as a sensory marker of phenolic richness and nutraceutical value, linking sensory science with olive ripening and informed consumer choice. Moreover, integrating chemesthetic mechanisms with phenolic chemistry, olive ripening physiology, and sensory methodology allows for a more comprehensive interpretation of EVOO quality beyond commercial classifications. Future studies combining chemical profiling, dynamic sensory methods, and consumer-focused research will be essential to refine quality-assessment tools and promote a deeper appreciation of the sensory diversity and functional value of high-quality EVOOs
Deeper, faster, stronger? Extreme magma ascent rates and explosive eruption metrics at Stromboli volcano (Italy)
No full textDetermining the ascent rate of magma during its rise to the surface is challenging yet crucial as it may relate to the style of volcanic eruptions, and modelling dissolved volatiles in crystal-hosted melt embayments is one effective method to estimate these rates. Previous studies suggest that magma ascent rates in basaltic volcanoes may positively correlate with eruption magnitude. Stromboli volcano (Italy) is an ideal case study because its unique plumbing system produces eruptions with variable eruption styles and magnitudes. Magma ascent rates of eight historical eruptions were calculated using (1) diffusion of H2O in embayments, and (2) vesicle population and textural analysis. Embayments record rapid ascent initiation from 1.6 to 7.2 km deep. We obtained average decompression rates of 0.32–6.2 MPa·s−1 (ascent rate of 11–226 m·s−1) for the last step of magma ascent within the conduit system, which agrees with Li diffusion in plagioclase and the timescales of ground deformation at Stromboli recorded immediately before explosive events. Vesicle number density of tephra clasts provides decompression rates within the same order of magnitude (0.55–6.09 MPa·s−1), confirming shallow very fast ascent within the conduit. We identify a strong positive correlation between decompression rates with (1) eruption magnitude, (2) mass eruption rate and (3) embayment H2O-CO2 solubility pressure for eruptions spanning several orders of magnitude in intensity, with faster decompression rates from greater pressures producing the highest intensity eruptions. We suggest such behaviour should be expected at other basaltic volcanoes as well
Le società a responsabilità limitata in house providing
No full textIl contributo sintetizza e commenta i risultati di un'analisi empirica avente a oggetto l'esercizio dell'autonomia statutaria nelle s.r.l. a partecipazione pubblica e, in particolare, delle s.r.l. in house providing
Integrated Constrained Manifold Optimization for Wideband OFDM-DFRC Hybrid Beamforming
No full textHybrid beamforming (HBF) offers a cost effective solution for multiple-input multiple-output dual-functional radar-communication (MIMO-DFRC) systems by reducing hardware complexity and power consumption. While narrowband HBF has been widely studied, wideband HBF design, particularly for transceiver-side hybrid architectures, remains rather underexplored. Existing HBF methods for wideband MIMO-DFRC systems typically adopt a sequential optimization (SO) framework based on the consensus alternating direction method of multipliers (CADMM), assuming a fully digital receiver architecture during the initial optimization stage. This assumption restricts the design flexibility and limits the achievable spectral efficiency (SE) on the communication side. To this end, an integrated constrained manifold optimization (ICMO) framework is proposed. The ICMO method embeds the transmit and receive HBF matrices, subject to constant modulus (CM) and transmit power per subcarrier, into an integrated variable and projects them onto an ICM-space for joint optimization. This transforms the original constrained problem into an unconstrained manifold optimization problem. Subsequently, a parallel simplified quasi-Newton (PSQN) method is developed to optimize the integrated variable within the ICMO framework, ultimately yielding the transmit and receive HBF coding matrices. Simulation results under a Pareto behavior analysis show that the proposed method dominates the CADMM baseline across the SSME and SE frontier, achieving up to 40% higher SE at comparable SSME and about 4.4 dB lower sidelobe levels, thereby enabling spectrum efficient and low sidelobe DFRC design
Angiogenesis before 2000—Cardiovascular system and angiogenesis during the centuries.
No full textUnlike other organs of the human body, the cardiovascular system has attracted human curiosity for its features. Indeed, since ancient times, the beating heart and the red color of blood flowing inside vessels were investigated for anatomical research, but they also inspired metaphorical as well as symbolical interpretations. Thus, for a very long time, the cardiac pump was thought as the seat of passions, leading to the development of the haemocardiocentric theory, especially in Aristotle’s medicine and philosophy. After the long-lasting Galen’s medicine, new anatomical discoveries were made in the Renaissance period, with more correct observations of the cardiovascular system by Leonardo da Vinci and Andreas Vesalius. Descartes’ mechanistic approach confirmed the discovery of blood circulation by William Harvey, whereas histological investigations unrevealed the capillary network. These studies mainly describe blood vessels as static anatomical structures with poor information about their formation and development. At the end of the 18th century, surgeon John Hunter introduced the novel concept of angiogenesis in in vivo experiments, leading to modern embryological research. Thus, the pioneer angiogenesis observations were characterized by the first microscopic evidence of capillary formation and the discovery of the angioblasts by Florence Sabin. A turning point of angiogenesis concept was marked in the 1970s of 20th century with the pivotal works by Judah Folkman and the study of pro- and antiangiogenic factors, which characterized the next two decades of angiogenesis research. New recent models of neovascularization have been proposed, including vasculogenic mimicry and vessel cooption to explain the nonangiogenic tumor growth and the antiangiogenic drug unresponsiveness. Future trends aim to explore the role of the angiogenic process and immunity. © 2026 Elsevier Inc. All rights reserved
Falsi e pie frodi: Ennio nel XX secolo
No full textThe article situates itself within the historical and philological debate on literary and documentary forgeries, proposing as an exemplary case study the alleged recovery of Ennius’ Thyestes by Father Pellegrino Ernetti. Following a comparative survey of well-known forgeries from antiquity to the modern period—from the Constitutum Constantini to the Poems of Ossian, and from the de situ Britanniae to the Carte d’Arborea—the article examines the cultural, ideological, and psychological mechanisms that foster the creation and temporary credibility of forged texts. The core of the discussion is devoted to Alessandro Russo’s meticulous investigation of the Thyestes of Ennius purportedly recovered by Father Pellegrino Ernetti. Russo’s analysis demonstrates that the “previously unknown” verses of the tragedy derive largely from translations and retroversions of Greek poetic and musical texts, mediated through twentieth-century anthologies, rather than from the authentic recovery of an archaic Latin text. The article further explores the personal and cultural motivations that led Ernetti to construct the forgery, relating them to the broader mythology of the chronovisor and to the relationship between philology, science-fictional imagination, and twentieth- century media culture. What emerges is a reflection on forgery as a historical product, capable of revealing both the vulnerabilities and the expectations of the scholarly community that receives it