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Flexible Automatic Design of GaN PA Based on Gaussian Process-Assisted Non-Dominated Sorting Genetic Algorithm
No full textThis paper introduces a new method for designing power amplifiers (PAs) using a flexible, automatic approach. It employs a Gaussian process-assisted fast non-dominated sorting genetic algorithm (GP-NSGA-II) for both circuit synthesis and layout optimization. Traditional genetic algorithms are computationally intensive and have poor convergence, making them difficult to use with three-dimensional full-wave simulators. To address these issues, the authors incorporate Gaussian process regression from Bayesian optimization into NSGA-II, improving convergence and computational efficiency. The method integrates layout simulation and optimization, enabling automatic PA design with direct layout optimization. To demonstrate the method’s effectiveness, the authors design a wide-band PA and a tri-band PA using a 10-W gallium-nitride (GaN) high electron mobility transistor (HEMT). The tests show that the prototypes perform well: the wide-band PA has a power-added efficiency (PAE) of over 61% and an output power greater than 41.5 dBm in the 2-3 GHz band, while the tri-band PA achieves PAE values of over 59%, 55%, and 57% in the 0.7-1.1 GHz, 2.3-2.5 GHz, and 3.4-3.5 GHz bands, respectively, with output powers exceeding 41.2 dBm, 40.6 dBm, and 40.6 dBm
Sustained Antifungal Protection of Peanuts Using Encapsulated Essential Oils
No full textEssential oils (EOs) are promising bio-preservatives for oilseeds; however, their high volatility and strong aroma limit practical applications. In this study, we developed a dual-size microencapsulated formulation of oregano (Origanum compactum) and myrtle (Myrthus communis) EOs (75:25, w/w) using gelatin–gum arabic complex coacervation, and evaluated its antifungal efficacy and effect on seed viability in peanuts. GC-MS analysis of the EO blend identified carvacrol (33.83%) as the dominant constituent. The microcapsules exhibited an encapsulation efficiency of 83.56% and were produced in a 70% small/30% large particle ratio to ensure both immediate and sustained vapor release. In vapor-phase assays against toxigenic A. flavus (RP-6), both free and encapsulated EOs inhibited fungal growth in a dose-dependent manner and achieved complete suppression at concentrations ≥0.2 μL mL−1, whereas the wall material alone showed no activity. In a 120-day microcosm storage experiment (0.2 mg EO g−1 kernels; 0.96 mg microcapsules g−1), treated peanuts showed an immediate reduction in total fungal load from 3.52 to 1.48 log10 CFU g−1 (≈58%), which stabilized near 1.42–1.43 log10 CFU g−1 up to 90 days, while the control samples increased to 4.25 log10 CFU g−1 by day 120. The formulation effectively suppressed major storage fungi, including Aspergillus sections Flavi and Nigri, Penicillium spp., Rhizopus, Fusarium, and Alternaria. The antioxidant activity (DPPH assay) was retained after encapsulation (IC50: 0.52 mg mL−1 encapsulated vs. 0.58 mg mL−1 free). Germination power remained comparable to the control throughout storage (≈50–52%), indicating no adverse impact on seed viability. These findings demonstrate that vapor-active, dual-size microencapsulation of oregano-myrtle EOs offers a practical and sustainable approach to enhance peanut safety during storage without compromising germination potential
GENERALIZED SKEW HOMODERIVATIONS IN PRIME RINGS
No full textOriginating from the study of noncommutative polynomials vanishing under all substitutions from a given algebra, the classical theory of PIs has evolved into a rich framework that connects combinatorial and structural aspects of algebraic systems, with matrix algebras playing a paradigmatic role.
A natural extension of this theory is provided by generalized polynomial identities (GPIs), in which coefficients may lie within the algebra itself.
Since Amitsur's foundational work and Martindale's generalization to prime rings, GPIs have been investigated in increasingly broad contexts, incorporating involutions, automorphisms, derivations, and anti-automorphisms, thereby yielding deep characterizations of prime and semiprime structures.
Within this lineage, derivations and their many generalizations, such as generalized derivations, skew derivations and generalized skew derivations, have been a persistent source of commutativity criteria and structural constraints.
Since the second half of the twentieth century, numerous authors have investigated generalized skew derivations that satisfy specific generalized polynomial identities on non-central Lie ideals of prime or semiprime rings.
Particularly notable is the concept of \emph{homoderivation}, introduced by El-Sofy, which unifies aspects of endomorphisms and derivations.
Recent developments, including -homoderivations, have expanded this idea, but the full structural potential of such mappings remains largely unexplored.
This dissertation advances the theory by introducing the notion of \emph{extended homoderivations}, additive maps from a prime ring into its right Martindale ring of quotients, associated with scalar parameters in the extended centroid.
These maps, together with their generalized, skew, and extended skew variants, subsume and unify classical concepts such as derivations, generalized derivations, homomorphisms, and their skew analogues.
The study systematically develops the theory of these mappings, extending and reformulating cornerstone results of Posner, Herstein, and others, and establishing new commutativity theorems in this broadened setting.
Special attention is devoted to the interaction between these mappings and structural components such as Lie ideals, centralizing conditions, and torsion-free hypotheses. The dissertation is organized to progressively build this framework: beginning with generalized homoderivations, it extends to the fully skew and extended contexts, culminating in a classification of the most general class considered, the \emph{extended generalized skew homoderivations}.
Applications illustrate the breadth of the theory, including analyses of subrings generated by images of the form and structural constraints arising from generalized Jordan-type identities.\\
More specifically, in the course of our analysis, we have undertaken a broad classification of the maps introduced, thereby providing a comprehensive and multifaceted picture of this emerging framework. Furthermore, we have presented an application that integrates various concepts and elucidates the precise structure of two generalized skew derivations, and , in the context where they act as a natural generalization of Jordan homoderivations.\\
\noindent In summary, this work situates extended homoderivations and their variants as a unifying theme in the theory of additive mappings on prime and semiprime rings, demonstrating how classical results on derivations naturally extend to a richer, more flexible setting.
By bridging and generalizing multiple strands of existing theory, it provides new tools and perspectives for the structural analysis of noncommutative rings
Minimal resolutions and algebraic properties of some classes of graded ideals
No full textThis thesis investigates the interaction between Combinatorics and Commutative Algebra, in order to study minimal resolutions and homological properties of graded ideals. In the exterior algebra, we construct minimal graded resolutions of monomial ideals with linear quotients via iterated mapping cones, describing their Betti numbers and differentials. In the polynomial ring, we develop the theory of vector-spread strongly stable ideals, generalizing both Macaulay and Kruskal-Katona theorems and describe an upper bound for their Betti numbers. For the class of squarefree principal vector-spread Borel ideals, we describe the primary decomposition and characterize the sequentially Cohen-Macaulay property. Moreover, we completely classify the ideals in this class having the property that their ordinary and symbolic powers coincide. For edge ideals of forests, we apply Betti splitting techniques to their squarefree powers, proving the non-increasingness of the normalized depth function and computing regularity in terms of matching numbers, thus confirming a conjecture of Erey and Hibi. We further study binomial edge ideals, establishing the sequentially Cohen-Macaulayness of cycles, wheels, block graphs, and cones. Finally, we present the Macaulay2 package SCMAlgebras, which provides computational tools for testing the sequentially Cohen-Macaulayness
Pragmatica. Una Cassetta degli attrezzi
No full textChe cosa accade davvero quando parliamo? Pragmatica. Una cassetta degli attrezzi accompagna il lettore dentro il laboratorio vivo della comunicazione, dove le parole non si limitano a descrivere il mondo ma lo trasformano. Il volume mostra come intenzioni, gesti, contesto, prosodia e conoscenze condivise diano forma al significato, rivelando ciò che nelle conversazioni quotidiane opera sotto la soglia della consapevolezza. Attraverso esempi, strumenti analitici ed esercizi, unisce rigore teorico e chiarezza espositiva offrendo una guida pratica per interpretare impliciti, gestire turni di parola, riconoscere atti linguistici e costruire coerenza. Aprire questa cassetta degli attrezzi significa imparare a osservare il linguaggio mentre vive, perché la pragmatica restituisce spessore all’esperienza più umana che abbiamo, quella di capirci attraverso le parole
Smart waste-derived materials for feed application: chestnut shells and vine pruning biochar
No full textCarrier-assisted delivery is a key step for the successful targeted oral delivery of bioactive molecules in functional diets in livestock. The aim is to protect the biomolecule during gastric transit, and ensure its efficient release in the intestine. Biochar is the by-product of the thermochemical conversion of residual biomass in an oxygen-limited environment and has suitable physico-chemical and morphological properties to be a carrier. Two types of biochar were tested as carriers of egg white lysozyme (LY), selected as a representative of bioactive molecules both in terms of molecular size (MW 14.3 kDa) and antibacterial activity, for application in weaned pig feed. One biochar was derived from chestnut shells (CB) and the other from vine pruning (VB). An efficient and environmentally-friendly procedure for LY adsorption was developed, based on a solid/liquid process in mild conditions. The effects of the operating conditions, such as initial LY content, reaction time, and pH were also studied. The optimal conditions were found to be a maximum LY loading of 21–23 mgLY gCarrier−1. Both pristine and hybrid materials were extensively characterized by combining morphological and physico-chemical techniques to obtain information on LY allocation and interactions with the carriers. Preliminary experiments on lysozyme release were performed at pH = 3 and pH = 7, simulating the pH conditions of the stomach and intestine of the weaned pigs, respectively. The results showed a higher releasing capacity when the pH was increased from 3 to 7. Specifically, the release showed a slight increase from 0.8% to 1.2% as the pH shifted from 3 to 7 for CB, and from 1.5% to 2.3% for VB. These results confirmed that biochar can protect LY from the low pH, during the gastric transit, and that LY could be released in the gut. These two benefits are likely related to the homogeneous distribution of LY molecules at the carrier surface, which is facilitated by the interaction of charges of opposite signs
FLOURISHING AND TIME USE AMONG UNIVERSITY STUDENTS: PRELIMINARY EVIDENCE FROM AD HOC SURVEY DATA
No full textThis study examines the relationship between university students’ time use and
psychological flourishing, focusing on the mediating role of leisure. Using cross-sectional
survey data from the University of Messina (spring 2024) analysed with post-stratification
weights, a Generalized Structural Equation Model disentangle direct and indirect associations
between sociodemographic, attitudinal, and behavioural factors and eudaimonic well-being.
Active forms of leisure (volunteering, sport, and general leisure), are positively associated
with flourishing, whereas passive media use shows a negative link. Commuting indirectly
reduces flourishing by limiting participation in active leisure. Students with more traditional
gender-role attitudes report higher flourishing, possibly due to cultural value alignment. The
findings underscore the importance of promoting inclusive and meaningful leisure
opportunities to foster student well-being in higher education
Quantitative structure retention relationship applied to capillary scale liquid chromatography for the identification of phenolic compounds
No full textQuantitative Structure-Retention Relationship (QSRR) model was developed to predict retention data of phenolic compounds and elucidate their retention mechanisms under reversed phase conditions. Compared to a previous work (Laganà-Vinci et al., J. Chromatogr. A, 2024, 1730, 465,146), the chromatographic method was down-scaled to capillary liquid chromatography (cap-LC) scale, thus drastically reducing solvent consumption and obtaining a more eco-sustainable method with respect to conventional LC. Moreover, a linear gradient of the mobile phase was applied rather than a multi-step one, allowing the application of linear regression models (i.e. PLS (partial least squares)) and reducing overfitting risk. A dataset of 53 standard phenolic compounds was used for model building and validation, while an external set consisting in bergamot juice analytes was used to evaluate the goodness of the QSRR model. To face the challenging QSRR step of variable selection, different methods were evaluated to reduce the number of variables needed to build the model. The final selected variables were evaluated for their impact on retention mechanisms, and the robustness of PLS model was tested across three different injection methods allowed by instrument manufacturer, thus simulating model transferability between different instrumental setup. Linear retention indices (LRIs) were applied for retention data normalization to further enhance the robustness of QSRR models. The homologue series of 1-nitroalkanes was used for calculation of LRIs, taking advantage of the efficient coverage of the elution space from small and polar simple phenols to larger and medium polar structures
Leveraging the Chinese Remainder theorem for outband D2D name-based content delivery
No full textThe explosive growth of mobile data traffic demands scalable, resilient, and energy-efficient solutions for content dissemination, particularly at the network edge. In this context, 5G networks can rely on Outband Device-to-Device (O-D2D) communications, using technologies such as Wi-Fi Direct, to offload infrastructure, enhance coverage at the cell edge, and enable proximity-based services. However, O-D2D communications face critical challenges related to peer discovery, reliable data retrieval over lossy wireless links, and energy efficiency constraints. In this paper, we propose a novel framework that integrates Named Data Networking (NDN) and Chinese Remainder Theorem (CRT)-based fragmentation to support autonomous O-D2D content delivery. By leveraging name-based forwarding and in-network caching, NDN facilitates distributed content retrieval, making it inherently suited for dynamic and infrastructure-less D2D environments. CRT-based fragmentation, on the other hand, enhances reliability and energy efficiency by allowing data reconstruction from partial fragment sets, mitigating the effects of packet losses typical of wireless links. We implement the proposed architecture in ndnSIM v2.9, extending the NDN forwarding plane to support CRT-based multi-source
data retrieval. Simulation results demonstrate that our solution significantly improves content delivery and
energy efficiency compared to existing NDN retrieval schemes, particularly under lossy wireless conditions
Hydrochemical Evolution of Groundwater Under Landfill Leachate Influence: Case of the Tangier Municipal Site
No full textSustainable groundwater management is critical in semi-arid coastal regions, where municipal landfills pose a severe threat to aquifer integrity and long-term water security. However, there is still a lack of seasonally resolved hydrogeochemical monitoring around newly established landfills, particularly in rapidly urbanizing Mediterranean settings. This study assesses the hydrogeochemical impact of the newly operational Tangier Landfill and Recovery Center on local groundwater resources to inform sustainable remediation strategies. A combined approach was applied to samples collected in dry and wet seasons, using Piper and Stiff diagrams to trace facies evolution together with a dual-index assessment based on the Canadian (CCME-WQI) and Weighted Arithmetic (WAWQI) Water Quality Indices. Results show that upgradient waters remain of Good–Excellent quality and are dominated by Ca–HCO3 facies, whereas downgradient wells display extreme mineralization, with EC up to 15,480 μS/cm and Cl− and SO42− exceeding 1834 and 2114 mg/L, respectively. At hotspot sites P4 and P8, As reaches 0.065 mg/L and Cd 0.006 mg/L, far above the WHO drinking-water guidelines. While the CCME-WQI captures the general salinity-driven degradation pattern, the WAWQI pinpoints these acute toxicity zones as Very poor–Unsuitable. The study demonstrates that rainfall intensifies toxicity through a seasonal “Piston Effect” that mobilizes stored contaminants rather than diluting them, underscoring the need for seasonally adaptive monitoring to ensure the environmental sustainability of landfill-adjacent aquifers