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Classification of Large Data Sets by Neural Networks: A Probabilistic Viewpoint
No full textA probabilistic approach to the classification of large data sets is presented. For data drawn from distributions that do not satisfy the naive Bayes assumption (when the presence of features is not independent of one another), conditions on the distributions are given that guarantee the almost deterministic behavior of errors in approximation by neural networks. It is shown that mean values of correlations with network computational units, together with the growth of sizes of their sets of input/output functions, can be used to assess the suitability of networks for classes of tasks characterized by probabilities modeling their relevance for a given type of applications
Dare conto di sé. Critica della violenza etica
No full textCosa vuol dire dare conto di sé? Soprattutto, cosa vuol dire farlo quando la nostra soggettività rimane sempre, in parte, opaca a noi stessi?
Judith Butler affronta questa domanda cruciale per ogni impianto morale, mostrando come l’impossibilità di un’auto-narrazione del tutto trasparente non sia un limite da superare, ma il fondamento di un’etica non-violenta.
A vent’anni dalla prima pubblicazione, Dare conto di sé continua a interrogare le nostre nozioni di responsabilità, alterità e riconoscimento. In dialogo serrato con Adorno, Foucault, Lévinas, Cavarero e Nancy, Butler propone una visione dell’etica come relazione costitutivamente esposta all’altro, segnata da un’incompiutezza strutturale, e proprio per questo aperta a forme di altruismo e umiltà.
Nel respingere l’ideale di un io sovrano, padrone e autosufficiente, Butler mette in discussione ogni pretesa di fondare la responsabilità su una trasparenza compiuta; senza ridurre il soggetto al relativismo né al nichilismo, ci invita a riconoscere l’opacità e la vulnerabilità come tratti comuni dell’umano. E immagina una nuova nozione di moralità che ponga al centro del nostro agire la generosità nei confronti degli altri, il mutuo riconoscimento della nostra fallibilità.
In un mondo che ci esorta sempre più a definire in maniera netta la nostra identità, Dare conto di sé riappare, in questa nuova edizione arricchita da una prefazione inedita, come un viatico necessario per interpretare le crisi e le tensioni contemporanee
PRESOL: A web-based computational setting for feature-based flare forecasting
No full textSolar flares are the most explosive phenomena in the solar system and the main trigger of the events’ chain that starts from Coronal Mass Ejections and leads to geomagnetic storms with possible impacts on the infrastructures at Earth. Data-driven solar flare forecasting relies on either deep learning approaches, which are operationally promising but with a low explainability degree, or machine learning algorithms, which can provide information on the physical descriptors that mostly impact the prediction. This paper describes a web-based technological platform for the execution of a computational pipeline of feature-based machine learning methods that provide predictions of the flare occurrence, feature ranking information, and assessment of the prediction performances
A Branch & Bound Algorithm for the Rainbow Spanning Forest Problem
No full textIn this paper, we present a Branch & Bound algorithm for solving an NP-hard combinatorial optimisation problem denoted as Rainbow Spanning Forest Problem (RSFP). The RSFP consists of finding a spanning forest of an undirected, edge-coloured graph G with the minimum number of rainbow components, where a rainbow component of G is a subgraph of G that has all the edges with different colours. The proposed method is capable of determining the optimal solution within 0.4 s for small instances, thus proving to be computationally competitive with respect to the methods used by the most recent optimisation libraries and commercial SW environments available
Customizable 3D-printed scaffolds for meniscal replacement: Mechanical insights into urethane-based poly(ethylene glycol) polymer
No full textThe menisci, essential fibrocartilaginous structures within the knee joint, play a critical role in load distribution, stability, and shock absorption. Meniscal injuries can result from acute trauma, degeneration, or arise as secondary consequences of other knee pathologies. Meniscus regeneration has emerged as a promising approach to address these challenges by developing biomimetic replacements that restore native function. The mechanical properties of scaffold materials are pivotal in the success of meniscus regeneration, given the complex and dynamic loading environment within the knee joint.
This study presents a comprehensive mechanical characterization of a novel scaffold material—acrylate end-capped urethane-based poly(ethylene glycol) (AUP)—designed specifically for meniscus regeneration applications. AUP is a synthetic polymer that demonstrates remarkable potential due to its tuneable mechanical and structural properties. This work focuses on evaluating AUP’s mechanical performance and its implications for fabricating functional meniscal constructs. Key mechanical properties analyzed include the tensile Young’s modulus (3.19–3.49 MPa), compressive modulus (2–3.32 MPa), storage modulus (5.76–8.2 MPa), loss modulus (0.08–0.14 MPa), swelling degree (200–295 %), gel fraction (>88 %), and fatigue durability (target 200,000 cycles). Utilizing advanced 3D printing techniques, the AUP hydrogel scaffold structure is customized to replicate the mechanical behavior of distinct meniscal zones.
This paper underscores the critical importance of mechanical characterization in developing AUP-based scaffolds for effective meniscus regeneration. The integration of mechanically optimized scaffolds offers a pathway toward restoring joint function, alleviating pain, and improving the overall quality of life for patients affected by meniscal damage
The ABA/LANCL1-2 system in ROS regulation in cardiomyocytes and in skeletal muscle differentiation and thermogenesis: evaluation of potential LANCL2 agonists
No full textAbscisic acid (ABA) is an evolutionarily conserved hormone that originated in some of the earliest living organisms, with modern ABA-producing cyanobacteria likely representing their descendants. Its emergence occurred prior to the divergence of the plant and animal kingdoms, and its fundamental role as a signaling molecule mediating cellular responses to environmental stress has been maintained throughout evolution. In mammals, beyond its anti-inflammatory and neuroprotective functions, ABA at nanomolar concentrations modulates the metabolic response to glucose availability by promoting glucose uptake in skeletal muscle and adipose tissue through an insulin-independent mechanism. Moreover, ABA enhances mitochondrial energy production and energy dissipation in both brown and white adipocytes via activation of its receptors LANCL1 and LANCL2. Chronic oral administration of ABA at microgram-per-kilogram body weight doses has been reported to improve glycemic control, lipid homeostasis, and morphometric parameters in borderline subjects for prediabetes and metabolic syndrome.
In rat H9c2 cardiomyocytes the cross-kingdom stress hormone ABA and its mammalian receptors LANCL1 and LANCL2 modulate the cellular response of cardiomyocytes to hypoxia by activating the AMPK/PGC-1α axis. This activation enhances increasing NO generation, mitochondrial proton gradient, respiration, and improves cell vitality after hypoxia/reoxygenation. In addition, overexpression of LANCL1/2 in rat H9c2 cardiomyocytes markedly increased, whereas silencing decreased, mitochondrial number, OXPHOS complex I activity, proton gradient, glucose- and palmitate-driven respiration, uncoupling protein transcription, and expression of proteins involved in cytoskeletal, contractile, and electrical functions. These effects, together with LANCL1/2-dependent NO production, are mediated by the transcription factor ERRα, which acts upstream of the AMPK/PGC-1α axis and is transcriptionally regulated by the ABA/LANCL1/2 system.
Based on this evidence, this thesis investigated the role of the ABA/LANCL1-2 system in Reactive Oxygen Species (ROS) metabolism in H9c2 cardiomyocytes overexpressing or silenced for LANCL1/2, with or without concomitant ERRα knockdown. Expression of enzymes involved in ROS production and scavenging was assessed by qRT-PCR and Western blot, while mitochondrial proton gradient and ROS levels were measured using specific fluorescent probes. LANCL1/2 overexpression decreased ROS-generating enzymes, increased ROS-scavenging enzymes, and reduced mitochondrial ROS, whereas opposite effects were observed in LANCL1/2-silenced cells. The knockdown of ERRα abrogated all beneficial effects on ROS turnover in LANCL1/2 overexpressing cells. Overall, these results indicate that the ABA/LANCL1-2 system regulates key aspects of cardiomyocyte physiology and ROS turnover via the ERRα/AMPK/PGC-1α axis, highlighting it as a potential target to enhance mitochondrial function and resistance to oxidative stress. Investigating molecules that specifically activate this system and its receptors represents a promising research avenue. To this end, biochemical assays in H9c2 cells and preliminary binding studies were conducted to assess the interaction of novel potential agonists with human recombinant LANCL2. Recent findings in rat H9c2 cardiomyocytes have demonstrated that the ABA/LANCL1-2 system plays a role in regulating cellular thermogenesis, as evidenced by higher heat production in LANCL1/2-overexpressing cells compared with double-silenced cells. These results are consistent with previous observations in adipocytes and myoblasts, which revealed an enhanced browning process accompanied by an increased basal metabolic rate, elevated substrate oxidation, and upregulated expression of uncoupling proteins. These proteins dissipate the mitochondrial proton gradient to generate heat instead of ATP, thereby contributing to cellular energy expenditure, mechanisms that are crucial for maintaining normal body weight and counteracting obesity.
In this thesis the potential role of the ABA/LANCL1-2 system in regulating the expression of genes involved in skeletal muscle thermogenesis and differentiation was investigated, aiming to provide further insights into the physiological functions of skeletal muscle, a tissue that constitutes approximately 40% of total human body weight and, together with adipose tissue, represents the majority of mammalian cell mass, significantly contributes to body weight balance
Individual Differences in Social and Emotional Responses to Robotic Dining Companions: Toward Personalized Interaction Design
No full textThis study investigates how affective and personality traits shape users’ emotional and social responses to a robotic dining companion in a commensal context. The companion is a NAO robot, equipped with a GPT-based dialogue and a commensal activity visual detection module, able to engage in mealtime conversation and exhibit responsive nonverbal behaviors. Twenty-two participants shared a meal with the robot and completed pre- and post-interaction measures of personality, affect, commensality habits, enjoyment of the interaction, and perceived social connection. Results showed that participants high in openness reported greater enjoyment of the interaction and more positive situational affect, while those high in negative trait affect also reported high enjoyment of the interaction, suggesting that the robot provided value even for users who were not predisposed to feel good. Perceived social connection was predicted by negative affect, frequency of eating with others, and technology use during meals. Traits like extraversion and agreeableness were inversely related to connection—suggesting that artificial social agents may resonate most with emotionally sensitive users, rather than the most sociable ones. These findings suggest that commensal robotic companions may be particularly well-suited to users high in negative affect and openness, but also highlight the importance of adapting dialogue and behavioral strategies to users’ personality traits
A Multi-Faceted Approach to Uncover Novel Vulnerabilities in Uveal Melanoma: From Etiology to the Identification of Prognostic Biomarkers.
No full textBackground. Uveal Melanoma (UM) is the most common primary intraocular malignancy in adults. Its clinical management, in the metastatic state, remains a significant challenge,
characterized by inherent aggressiveness and limited systemic therapeutic options. Despite substantial progress in genomic prognostic stratification, the unpredictable nature of the disease in some patients and the lack of effective treatments underscore the urgent need for a deeper understanding of both etiological factors and molecular mechanisms driving progression.
Aims. This study adopted a multi-faceted approach focused on three main objectives: i) To elucidate the potential etiological role of Blue Light (BL) exposure; ii) To develop genetically defined cellular models to reproduce the key molecular alterations of aggressive UM (GNA11 and BAP1 mutations); and iii) To identify and validate novel prognostic biomarkers within the Chromosome 8q gain region.
Results. BL exposure in melanocyte models generated mutational signatures (SBS1 and SBS5) aligned with those typical of UM, providing direct evidence that BL may act as an "additional hit" in tumorigenesis, distinct from UV-induced damage. Unexpectedly, a BL complex oxidative stress response was observed, characterized by an overall increase in ROS but a reduction in H2O2 production. In parallel, the first GNA11Q209L cellular models were successfully generated to reproduce the key alterations driving aggressive UM for in vitro and in vivo functional studies. Furthermore, bioinformatic, immunohistochemical and NGS analysis of two UM’s patients cohorts for the Chr 8q status identified NDUFB9 and LAPTM4B as potential functional drivers, whose expression enabled the development of a robust Multigene Score (MGS) highly potent in stratifying patients at high risk of disease-specific mortality.
Conclusion and Discussion. This work provides novel etiological insights into the potential role of BL and introduces a reliable prognostic tool (MGS) superior to single markers. The identification of NDUFB9 (involved in mitochondrial metabolism) and LAPTM4B (implicated in autophagy and drug resistance) as probable functional drivers of the metastatic phenotype suggests these genes are not merely passenger, but represent promising therapeutic targets, particularly within the context of UM's intrinsic resistance. Further functional validation of these genes is crucial. Future studies will focus on completing the creation of more complex in vivo mouse models (GNA11+BAP1) for metastatic evaluation. Furthermore, the application of spatial transcriptomics (Xenium) on metastatic samples treated with Tebentafusp will be essential to map therapeutic cellular interactions within the tumor microenvironment and spatially validate the 8q drivers at high resolution, guiding the next generation of treatment strategies
Mechanistic insights into the effects of Fluoxetine in Mytilus galloprovincialis using in vivo and in vitro approaches
No full textAntidepressants such as selective serotonin reuptake inhibitors (SSRIs) are pseudo-persistent contaminants in
aquatic ecosystems. While their effects and molecular targets are relatively well understood in vertebrates, less
information is available in aquatic invertebrates. In this work, the effects and mechanisms of action of Fluoxetine
(FLX), a widely prescribed SSRI, were investigated in the model marine bivalve Mytilus galloprovincialis. In vitro
exposure of isolated hemocytes to FLX (0.03–0.3–3 μg/mL) induced significant alterations in immune and
lysosomal parameters. In mussels exposed to FLX or its active metabolite norfluoxetine NFL (0.5–5–10–50 ng/L,
7 days), a concentration dependent accumulation of either compound was observed in the digestive gland. NFL
was also detected in FLX-exposed mussels, indicating biotransformation. FLX and NFL affected transcription of
monoamine receptors, and of lysosomal, autophagy, and ceramide related genes, with a distinct pattern for each
compound, with FLX mainly inducing downregulation of gene expression. The results demonstrate that in
mussels both FLX and NFL act through multiple molecular pathways, pointing at the lysosomal system as a main
target for both compounds. These data provide novel mechanistic insights into antidepressant toxicity in a nontarget
marine invertebrate and contribute to draw Adverse Outcome Pathways for SSRIs in bivalves, that
represent foundation species in coastal environments
