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Velocity Inequalities in Digital Public Service Ecosystem: David Against Goliath in the Agri-Food Value Chain?
No full textDigital transformation is fundamentally reshaping public service ecosystems (PSEs), generating velocity asymmetries that influence governance structures, service interactions, and power dynamics, contributing to a paradigm shift from traditionally industrially oriented ecosystems to service logic. Addressing key gaps in previous PSE studies, this research examines how digital transformation shapes velocity inequalities among different actors. The agri-food sector was selected as the empirical context due to the profound digital and structural transformations currently reshaping its ecosystem and governance mechanisms. This study adopts a qualitative, multi-method approach, combining a systematic desk review and participatory observation within a stable smart agri-food network with strong European linkages. Findings indicate that tech giants and startups operate at high velocity, leveraging data-driven service innovation, whereas small farmers and public institutions struggle to adapt due to resource constraints, bureaucratic inertia, and fragmented digital governance. The study highlights the emergence of data-centric service models, underscoring the need for strategic public–private coordination to ensure equitable participation in the evolving PSE. By advancing theoretical insights on velocity inequalities in PSEs, this research contributes to a deeper understanding of how governance mechanisms and institutional adaptation shape service-driven digital transitions in complex, multi-actor ecosystems
INVITUS. THE UNWILLING BETWEEN STATE OF MIND AND DECLARATION
No full textIn Roman legal and literary sources, the adjective invitus occurs in disparate contexts and with meanings and values that are often ambiguous. Starting from the doctrinal debate of the nineteenth and twentieth centuries on the legal will, this essay will be dedicated to investigating both the link between will, non-will and vices of the will, in the light of the possible interpretations of the Latin term invitus, and the possibility of using the ideas from the Roman sources relating to the invitus to reason on the category that has recently spread in the jurisprudence and doctrine of vulnerability
Crowdfunding and the art market. Rise and regulation of contemporary forms of patronage
No full textPromoting art and culture is crucial for the development of any human society. Nevertheless, such goal is often not included (or even considered) among the priorities of countries’ politics and this is mainly due to the absence of adequate public funding. In this context, an important role has been played by the implementation of crowdfunding platforms. Still, in the authors’ view, the legal framework currently existing in Italy fails to encourage this potential, especially when it comes to the visual arts. This is because, to date, the sole public incentives for crowdfunding are provided under the so called ‘Art Bonus decree,’ which accords fiscal benefits only to those people investing in the restoration of publicly owned artworks. In this respect, the present chapter draws a distinction between campaigns on contemporary visual art and campaigns on existing visual art, finding that public fundings (if any) only address the second category
Capitale, Terra, Sapiens e un ecocompagno di strada
No full textL’analisi scientifica e politica del cambiamento climatico condotta da Mario Tozzi nel suo Caro Sapiens (Mondadori), mostra diversi punti di contatto tra divulgazione scientifica, ecomarxismo e giornalismo d’inchiesta ambientale
Mathematics teacher noticing: a situated Taxicab lab experience connecting research and practice-based teacher development
No full textThis paper investigates how an extracurricular Taxicab-geometry lab for secondary students functioned as a practice-based professional learning space for two in-service teachers. Observing an expert teacher, participating teachers developed professional noticing of student thinking and moves that support mathematical learning. Using the Attending–Interpreting–Deciding framework to analyse observation notes, debriefing dialogues, and reflective questionnaires, we found evidence that trajectory-based tasks, dynamic digital tools, and specific orchestration moves catalysed teacher noticing. Findings suggest that observing expert practice in authentic settings can shift teachers' professional stance toward designing principles for their own classrooms
A lightweight blockchain-based defense method for federated self-supervised learning
No full textIn recent years, deep learning technologies have experienced significant advancements, especially in the computer vision area. However, their success depends heavily on the availability of vast amounts of labeled data, introducing several data-gathering issues. To cope with these limitations, we use Federated Self-Supervised Learning (FedSSL), a framework that integrates Self-Supervised Learning (SSL) with Federated Learning (FL). FedSSL uses unlabeled data to enhance model performance and generalization without compromising data privacy. Despite its advantages, our research reveals vulnerabilities in FedSSL, such as susceptibility to model poisoning attacks. We introduce a Blockchain-based defense method for FedSSL (BCH-FedSSL) to face this risk, which incorporates blockchain technology to decentralize model aggregation, ensuring data integrity and transparency. Experimental results conducted under IID data distributions using the CIFAR-10, CIFAR-100, and Fashion-MNIST datasets demonstrate that BCH-FedSSL's effectiveness in maintaining model accuracy and robustness under adversarial conditions. The proposed method achieved, in the presence of a poisoning attack, a 30 % performance improvement on CIFAR-10, a 27 % on CIFAR-100, and a 31 % on Fashion-MNIST. This study highlights the potential of combining blockchain with federated learning to create secure, scalable, and efficient decentralized learning systems
Limit to Self-Field Critical Current Density in Thin-Film, Type-II Superconductors
No full textIn the last decade, the self-field critical current density Jc(s.f.) in Type-II superconductors
has been considered fundamentally limited by a Silsbee-like criterion of Jc(s.f.) = Hc1/λ. We
show that this universal limit to self-field critical current density Jc(s.f.) is not universally
valid. We present several examples for this in YBa2Cu3O7−δ-type and REBa2Cu3O7−δ
thin films and one for Nb thin films and show that calculated Jc(s.f.) using the Silsbee-like
criterion using thermodynamic parameters has been substantially exceeded experimentally.
We also show that Jc(s.f.) can be significantly improved by incorporation of artificial
pinning centers (APCs), further implying that no such universal limit to Jc(s.f.) can exist
because such an upper bound, Jc(s.f.) would have to be independent of APCs. These
findings call for a revision of the accepted understanding of current-carrying limits in
Type-II superconductors and reveal substantial potential for improving Jc in REBCO-based
coated conductors through optimization of APCs for large-scale applications, including
commercial nuclear fusion
Symmetry breaking and avalanche shapes in modular neural networks
No full text: Modularity is as a key characteristic of structural and functional brain networks across species and spatial scales. We investigate the stochastic Wilson-Cowan model on a modular network in which synaptic strengths differ between intra-module and inter-module connections. The system exhibits a rich phase diagram comprising symmetric (with low and high activity) and "broken symmetry" phases. Symmetric phases are characterized by the same low or high activity in all the modules, while the broken symmetry phases are characterized by a high activity in a subset of the modules and low activity in the remaining ones. There are two lines of critical points, the first between the low activity symmetric phase and the high activity symmetric phase, and the second between the low activity symmetric phase and a broken symmetry phase with one active module. At those lines the system shows a critical behavior, with power law distributions in the avalanches. Avalanche shapes differ systematically along the two lines: they are symmetric or right-skewed at the transition with the symmetric phase, but become left-skewed over intermediate durations along critical line with the broken symmetry phase. These results provide a theoretical framework that accounts for both symmetric and left-skewed neural avalanche shapes observed experimentally, linking modular organization to critical brain dynamics