Archivio istituzionale della ricerca - Università dell'Insubria
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Convergence analysis and parameter estimation for the iterated Arnoldi-Tikhonov method
No full textThe Arnoldi-Tikhonov method is a well-established regularization technique for solving large-scale ill-posed linear inverse problems. This method leverages the Arnoldi decomposition to reduce computational complexity by projecting the discretized problem into a lower-dimensional Krylov subspace, in which it is solved. This paper explores the iterated Arnoldi-Tikhonov method, conducting a comprehensive analysis that addresses all approximation errors. Additionally, it introduces a novel strategy for choosing the regularization parameter, leading to more accurate approximate solutions compared to the standard Arnoldi-Tikhonov method. Moreover, the proposed method demonstrates robustness with respect to the regularization parameter, as confirmed by the numerical results
Fabio Minazzi e la costruzione, a Varese, di un archivio nazionale dei manoscritti filosofici
No full textX-Ray Investigation of Possible Super-Eddington Accretion in a Radio-loud Quasar at z = 6.13
No full textWe present radio and X-ray observations of the recently discovered z = 6.13 radio-powerful quasar RACS J032021.44−352104.1 using the upgraded Giant Metrewave Radio Telescope, the Australia Telescope Compact Array, the Australian Large Baseline Array, and Chandra. The observed radio properties are in line with what is typically observed in high-z radio quasars (αr = 0.72 ± 0.02 and L1.4 GHz = 5.8 ± 0.9 × 1026 W Hz−1). Despite the relatively low X-ray flux observed, F0.5−7.0 keV = 2.3 ± 0.5 × 10−14 erg s−1 cm−2, the intrinsic luminosity in the 2-10 keV rest frame is markedly high, L 2 - 10 keV = 1 . 8 − 0.7 + 1.1 × 1 0 46 erg s−1, making RACS J032021.44−352104.1 one of the most luminous quasars currently known at z > 5.5. The high X-ray luminosity is largely driven by an extrapolation to energies below the observable X-ray window with Chandra and the slope derived in the 0.5-7 keV band (or 3.5-50 keV in the rest frame; ΓX = 3.3 ± 0.4). By analyzing the overall spectral energy distribution of the quasar, we found that the remarkably soft X-ray emission (1) cannot be produced by relativistic jets, even when relativistic boosting is considered, and (2) is consistent with expectations for a super-Eddington accreting supermassive black hole. If such a high accretion rate was confirmed, this source would be a unique laboratory to study high accretion in the early Universe and could help resolve some challenges inherent in early black hole growth paradigms
Quantum-enhanced second harmonic generation beyond the photon pairs regime
No full textLong ago, it was predicted that stimulating two-photon processes such as two-photon absorption (TPA) and second harmonic generation (SHG) with entangled photons produced by parametric down-conversion (PDC) could result in higher efficiencies compared to classical illumination [1]. This was experimentally demonstrated for SHG [2] and TPA [3], where, however, the classical comparison was performed by adding losses to the PDC state rather than employing a true classical reference. In addition, these results considered spatially single-mode PDC radiation and were conducted at low photon fluxes, where the PDC modes are, on average, populated by less than one photon. This resulted in an extremely low SHG/TPA signal, considered of limited practical use for metrological applications (such as two-photon fluorescence microscopy or SHG imaging - see, e.g., [4]). A recent theoretical investigation [5] highlighted that a proper analysis of quantum-enhanced two-photon processes requires a fully spatiotemporal model of the nonlinear interactions. It further showed that highly multimode (in space and time) entangled PDC photons can provide a quantum advantage compared to an equivalent classical pulse, even in regimes well beyond the “one-photon-per-mode” limit, considered the boundary of quantum behavior
IL CENTAURO. Origini e sviluppo dell'iconografia e alcuni motivi insoliti nell'Italia preromana
No full textHow substrate depth shapes spontaneous plant colonisation on Mediterranean green roofs: A case study
No full textGreen Roofs (GRs) have been recognized by the EU as key Nature-based Solutions providing environmental and human benefits in cities. Mediterranean GRs (MGRs) are still rare and little is known about the successional dynamics and environmental factors shaping plant community composition. In the current study, we monitored spontaneous plant communities colonising two MGRs different in substrate depths and composition, and year of installation in the city of Genoa (NW Italy). Taxonomic composition variation over time was described using Non-Metric Multidimensional Scaling (NMDS) and species turnover rates. A nested ANOVA was used to test differences in plant biomass. Finally, functional composition variations were investigated by calculating CSR ecological strategies of species using the StrateFy tool, which identifies competitive (C), stress-tolerant (S) and ruderal (R) plant strategies. Both the taxonomic and functional structure of spontaneous plant communities were strongly dependent on MGR characteristics, with S species usually dominating on MGRs with shallower substrate, while deeper MGRs were also able to support more C species. However, the temporal variation in biomass and CSR strategy distributions indicates that substrate effects might be modulated by external interactive factors such as climate conditions and human disturbance. Our results show that, although described as extreme habitats, MGRs can support resilient, heterogeneous and dynamic spontaneous plant communities and that substrate plays a key role in driving their temporal evolution. From a planning perspective, our study demonstrates the importance of implementing a functional trait-based approach for species selection in MGRs, considering substrate-related factors and management practices
Unveiling the Prognostic Role of Synaptophysin in Conventional Colorectal Carcinomas
No full textIntroduction: Although neuroendocrine differentiation in colorectal carcinomas (CRCs) has been extensively reported, the biological behavior of adenocarcinomas expressing synaptophysin (Syn) but lacking typical neuroendocrine morphology remains unclear. Methods: We tested 663 conventional CRCs with non-neuroendocrine morphology for Syn expression and correlated the results with clinicopathological and molecular characteristics as well as patient survival (overall survival [OS] and disease-free survival [DFS]). The survival characteristics of Syn expression group were compared to those of conventional CRCs and subsequently to those of 14 minENs. Results: Syn immunohistochemical expression ≥30% was confirmed in 27 (4.1%) patients and correlated with right colon site, grade 2, marked intratumoral lymphocyte infiltrate, and BRAF p.V600E mutation. At univariate analysis, variables associated with poor OS were 10-year increase in age (0.001), stage III-IV (0.001), Syn ≥30% (0.001), infiltrative growth (0.04), and residual tumor R1-2 (0.03). At multivariable analysis, Syn expression in ≥30% of gland-forming tumor cells emerged as an independent negative prognostic factor for both OS and DFS. Moreover, 10-year increase in age, stage III-IV, and Syn ≥30% (p < 0.001) were associated with poor OS and marked peritumoral lymphocyte infiltrate with longer OS (0.02). Comparable results were obtained according to DFS; in addition, right colon site (0.04) was associated with longer DFS while KRAS mutation (0.04) was associated with poor DFS at univariate analysis. MiNEN patients showed a shorter DFS than all conventional adenocarcinomas with or without Syn expression in univariate analyses (p < 0.001). Conclusions: Among conventional CRCs, we provided evidence that Syn expression is associated with worse OS and DFS and contributes to predicting clinical outcome. Future studies should explore the molecular mechanisms underlying the acquisition of the neuroendocrine phenotype to identify new targeted treatment strategies
Baseline risk and outcome benefit from intensive blood pressure targeting. A systematic review
No full textBackground Randomized clinical trials (RCTs) comparing different blood pressure (BP) targets support more stringent systolic BP targets than previously recommended. We investigated the impact of baseline risk on the outcome benefit from intensive BP targeting. Methods We examined RCTs testing a tight systolic BP target (<120 mmHg) separately from trials testing a less tight (<125–140 mmHg) intensive target. Cardiovascular death and all-cause death were the primary outcomes of interest. We also examined stroke, heart failure and myocardial infarction. Results We included 11 trials, with a total of 63,090 patients. The more intensive systolic BP target was <120 mmHg in five trials and less intensive in six trials. Cardiovascular death was reduced in the <120 mmHg arm compared to the control arm (risk difference (RD) -4.61, 95 % CI -6.84 to -2.39; p < 0.0001), but not in the <125–140 mmHg arm compared to the control arm (RD -0.92, 95 % CI -2.62 to 0.78; p = 0.29). All-cause death was reduced in the <120 mmHg arm compared to the control arm (RD -5.23, 95 % CI -8.82 to -1.64; p = 0.0043), but not in the <125–140 mmHg arm compared to the control arm (RD 0.24, 95 % CI -3.16 to 3.56; p = 0.89). Examining the 11 trials as a whole, a relationship emerged between the level of risk for all-cause mortality and cardiovascular mortality in the control group and the magnitude of benefit in the group randomized to more intensive BP control. Conclusion A systolic BP target <120 mmHg consistently reduces all-cause and cardiovascular mortality. The higher the baseline risk, the greater the benefit of a more intensive BP target
Evolving frontiers in bladder cancer immunotherapy: integrating BCG, immune checkpoints, viral vectors, nanotechnology, and CAR-based therapies
Get PDFBladder cancer (BC) remains a prevalent malignancy with high recurrence rates despite standard therapies. Bacille Calmette-Guérin (BCG) is the cornerstone of treatment for non-muscle-invasive bladder cancer (NMIBC); however, nearly half of patients experience relapse or develop resistance, highlighting the need for alternative strategies. Recent advances in immunotherapy have reshaped the therapeutic landscape. Immune checkpoint inhibitors (ICIs) restore T-cell function and show clinical activity in BCG-unresponsive disease. Viral vector–based approaches, including nadofaragene firadenovec and CG0070, provide localized immune activation, while cellular platforms such as CAR-T and CAR-NK therapies offer precision targeting of tumor antigens. Concurrently, nanotechnology-based delivery systems and antibody–drug conjugates (ADCs) enhance efficacy and safety by improving tumor-specific cytotoxicity. Collectively, these strategies signify a paradigm shift from traditional intravesical therapy toward personalized and durable immunotherapeutic interventions. Identification of predictive biomarkers and rational combination strategies will be critical to improving outcomes and guiding the future management of BC
Concordato sui motivi di appello e regime delle impugnazioni
No full textL’accordo sui motivi di appello si pone in rapporto di continuità con la logica del secondo grado di giudizio e al tempo
stesso con i principi che informano il modello accusatorio del rito penale. Elementari esigenze di tutela del principio
di legalità postulano l’osservanza delle norme di carattere generale poste a tutela di interessi indisponibili, la cui
applicazione si impone anche nel giudizio di Cassazione successivo alla sentenza riproduttiva del concordato sui
motivi di appello. Sotto un diverso profilo, il lineare funzionamento del congegno negoziale postula il rispetto rigoroso, da parte della difesa e della pubblica accusa, dei canoni di correttezza processualeThe agreement between the prosecutor and the defendant before the Criminal Court of Appeal does not entail a
waiver of the right to appeal to the Supreme Court. This raises the issue of how to strike an appropriate balance
between the rule of law and the growing role of negotiated justice within appellate proceedings. In this context, the
fairness of the negotiation process should also be emphasized, particularly in light of the ethical foundations of the
adversary trial