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Reflectivity Reconstruction From Phaseless, Nonredundant Near-Field, Plane-Polar Data
No full textImage-based approaches allow estimating the reflectivity of a target from near-field (NF) measurements. We propose a new approach to reconstruct the reflectivity of a planar target from amplitude only data, whereby monostatic nonredundant NF data are used. A plane-polar scanning strategy is considered. The phaseless imaging problem is dealt with as a quadratic inverse one and requires two sets of independent amplitude measurements of the scattered field, collected on two different scanning surfaces. A nonredundant sampling representation of the squared amplitude of the NF data is worked out. A big reduction of about 94% of the requested NF samples, when compared with classical conservative \lambda 8 phaseless measurements, is achieved. No loss of accuracy is experienced with respect to the case when the reconstructions are performed by complex (i.e., amplitude and phase) data. Notably, the overall samples are even lower than those necessary to carry out a complex standard NF procedure on a solitary surface. The only available a priori information on the scatterer is the size of the enclosing box. This is accounted for by an effective representation of the reflectivity profile, thus improving accuracy and reliability of the phaseless technique. Numerical and experimental results assessing the effectiveness of the approach are presented
Sufficient conditions for the existence of asymptotically stable homeostatic equilibrium points in negative feedback physiological systems
No full textWhile the adoption of mathematical models to represent and describe physiological phenomena is widely applied in bioengineering, medicine, and biochemistry research, the large variety of physio- and bio-logical systems, as well as the complex dynamics involved in homeostatic control, prevent the definition of a generalized biofidelic modeling approach for the analysis of systems’ dynamics. Leveraging the formalism and principles of control theory, this manuscript lays the theoretical foundations for the study of self-regulatory mechanisms in multivariable negative feedback physiological systems. Starting from the definition of a system-theoretic oriented mathematical modeling framework, general assumptions and model-specific theorems, tailored to the order of the model, are derived and demonstrated to define sufficient conditions for the existence of unique and asymptotically stable equilibrium points within the system's operating regions. Then, the proposed methodological approach is translated into practice through application to relevant case studies representing physiological control systems at increasing degrees of complexity (from 2nd- to 4th-order models), namely: (i) the regulation of thyroid hormones circulation in the blood; (ii) the prey–predator model describing the dynamics of tumor progression; (iii) the cortisol dynamics in response of pain/stress stimuli. Finally, the capability of the proposed framework to effectively capture the behavior of additional physiological systems (from 2nd- up to 7th-order) available in the literature is also demonstrated, thus shaping a promising theoretical and methodological route for the analysis of uniqueness and stability of homeostatic equilibrium in both physiological and pathological conditions
A Conceptual Logistic–Production Framework for Wastewater Recovery and Risk Management
No full textWastewater management plays a critical role in advancing the circular economy, as wastewater is increasingly considered a recoverable resource rather than a waste product. This paper reviews physical, chemical, biological, and combined treatment methodologies, highlighting a lack of a holistic framework in current research which includes both the operational phases of wastewater treatment and proper risk analysis tools. To address this gap, an innovative methodological framework for wastewater recovery and risk management within an integrated logistic–production process is proposed. The framework is structured in five steps: description of the logistic–production process, hazard identification, risk assessment through the Failure Modes, Effects, and Criticality Analysis (FMECA), prioritization of interventions using the Action Priority (AP) method, and definition of corrective actions. The application of the proposed methodology can optimize the usage of available resources across various sectors while minimizing waste products, thus supporting environmental sustainability. Furthermore, political, economic and social implications of adopting the proposed approach in the field of energy transition are discussed
Deformed Wing Virus infection induces immunosuppression and gut dysbiosis in honey bees
No full textBackground: The global decline of honey bee health, driven by multiple stressors impairing immunity, threatens both natural and managed ecosystems. Deformed Wing Virus (DWV) is often found at high loads in collapsing colonies, associated with an immunosuppressive syndrome still poorly understood. This study investigates gut microbiota community patterns associated with different levels of DWV infection, an overlooked aspect which can contribute to the reduction of immunocompetence in infected honey bees. Results: We quantified DWV in nurse bees from the field and compared gut microbiota in individuals with high vs. low viral loads. We also examined microbiota changes in bees experimentally infected with DWV. In both cases, highly infected bees showed a decreased transcription level of dorsal 1-A, a consolidated molecular proxy of reduced immunocompetence in honey bees. Host immunosuppression was associated with a consistent gut dysbiosis, marked by a reduced relative abundance of beneficial genera such as Fructobacillus, Lactobacillus, and Apilactobacillus (Firmicutes, Bacilli), and a relative enrichment of Bartonella (Proteobacteria). Conclusions: These findings shed new light on host-pathogen interactions and will allow a targeted manipulation of honey bee gut microbiota to limit DWV infections, which strongly contribute to colony losses
Does the House Always Win? State Regulation, Market Dynimics, and Criminal Infiltration in the Italian Gambling Sector
No full textThis article analyzes Italy’s gambling regulation following its liberalization since the 1990s. While intended to boost public revenue and curb illegality, the system has fostered a hybrid environment where legal and illegal practices often coexist. Drawing on qualitative data, the study highlights fiscal inefficiencies, regulatory capture, and mafia infiltration. The state's dual role—as both regulator and beneficiary—has created structural tensions, reinforcing market expansion at the expense of public health and transparency. The authors argue for a critical reassessment of the current model, advocating for evidence based, multidimensional policies that balance fiscal goals with social and institutional safeguards
Searching the limits of compositionally complex AlB2-type diboride solid solutions for hypersonic applications
No full textCompositionally complex (CC) AlB2-type diboride solid solutions (DSSs) containing IV-V-VI group metals were investigated as candidate materials for hypersonic applications using a ground entry simulator. Each CCDSS was composed of Ti and three other transition metals among Zr-Hf-Nb-Ta. Single phase CCDSS dense discs were spark plasma sintered and then exposed to a supersonic dissociated airflow (nominal Mach 3). The overall degradation of the discs was highly dependent on the combination of starting metals, and massive preferential oxidation occurred. The coexistence of Nb and Ta was detrimental. A thermal study was devised and implemented in a numerical model to validate the experimental set-up. The experimental results also showed good agreement with predictions based on a thermodynamic assessment
A shelter for antiquity. An archaeological covering in Piazza Bellini in Naples
No full textThe city is made up of layers (strata) that are often invisible and difficult to understand, especially when there is no architecture to make them visible. This is the case of the 5th-4th century BC Greek walls in Piazza Bellini in Naples, which were discovered by chance in 1954 and left uncovered and inaccessible, covered and fenced off, unable to establish any clear relationship with the city “above”, which is organised according to a completely different order.
The project, the result of a workshop-internship with young female students, aims to rearrange the entire Piazza Bellini, located on the edge of the Greek-Roman centre of the city, starting from the need to protect, but also and perhaps above all to “reveal”, the walls whose presence risks going unnoticed due to the e absence of a synthetic design that today sees the cleared space represented in the 18th century by Antonio Joli unnecessarily crowded with trees, monuments – first and foremost that to the Catania-born musician Vincenzo Bellini, who trained in Naples at the Collegio di Musica di San Sebastiano, now the Conservatorio di San Pietro a Majella, adjacent to the square – outdoor seating areas and street furniture.
Once the excavation has been rationalised, a tall golden shelter reveals the rotated position of the walls, in the perforation and design of the paving, and finds its counterpoint in a portico that organises the outdoor spaces of bars, literary cafés and restaurants that “inhabit” the square, thus reintroducing the ruins into the urban dynamic and constructing a double register according to which the city reveals and does not pretend or conceal the millennial roots from which it originates. The golden yellow painted steel roof – ‘giallo Napoli’ – is intended as a shelter for the ancient, which, by echoing the alignments, heights and rhythms of the existing building facades, introduces a new urban singularity, called upon to characterize the public space, and, by sinking into the chthonic depths of the tuff, at the same time frees itself like a large pergola to signal the ancient remains it shades and protects. An abri souverain, as in Auguste Perret’s well-known definition, which in the accuracy of its proportions – a square in plan, two squares in elevation – and in the logical essentiality of its tectonic construction – four pairs of piers supporting two variable-section median beams, which in turn support a pergola trellis – has the task of implementing and staging – in opera et in scæna – the grandeur of the antiquity without mimicry but also without derision because, following Karl Kraus’s well-known aphorism, Ursprung ist das Ziel