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On the Lucas and Lehmer sequences in Dedekind domain
No full textIn this paper, we first obtain the strong divisibility property for the Lucas and Lehmer sequences
in Dedekind domains, and then establish analogues of Zsigmondy's theorem and the primitive divisor results for such sequences in function fields
Sfide del docente e nuove idee sulle sue competenze in una società in profondo mutamento (1960-1970). La prospettiva pedagogica della rivista «Scuola Italiana Moderna»
No full textEarly weight loss, diabetes remission and long-term trajectory after diagnosis of type 2 diabetes: a retrospective study
Get PDFAims/hypothesis: Weight loss can improve glycaemic management in individuals with type 2 diabetes, but its long-term effects on remission, cardiovascular risk factors and complications remain unclear. We investigated clinical outcomes following non-interventional ≥10% body weight loss in people with newly diagnosed type 2 diabetes in a routine care setting. Methods: We retrospectively analysed two cohorts of people with newly diagnosed type 2 diabetes. After exclusions, cohort 1 included 1934 individuals followed for up to 25 years; cohort 2 comprised 13,277 individuals followed for up to 10 years. Participants were categorised into two groups based on whether or not they lost at least 10% body weight. In a sensitivity analysis, a group of participants with intermediate weight loss (5% to <10%) was also considered. Outcomes included HbA1c, diabetes remission, cardiovascular parameters and chronic complications. Results: Participants (58% male) had a mean age of 62 years and a mean diab..
Great saphenous vein versus expanded polytetrafluoroethylene graft in patients undergoing elective treatment of popliteal artery aneurysm with a posterior approach
No full textBackground: The aim of this study was to compare 30-day and 5-year outcomes of great saphenous vein (GSV) vs expanded polytetrafluoroethylene (ePTFE) graft in patients undergoing elective treatment of popliteal artery aneurysm (PAA) using a posterior approach. Methods: Between January 2010 and December 2023, a retrospectively maintained dataset of all consecutive asymptomatic PAAs who underwent open repair with posterior approach or endovascular repair in 40 centers was investigated. Of 971 cases, 525 patients were included in the present analysis. These were further divided into posterior approach with GSV graft (252; GSV group), and posterior approach with ePTFE graft (273; ePTFE group). Thirty-day outcomes were assessed and compared. During follow-up, survival, primary patency, secondary patency, freedom from reintervention(s), and amputation-free survival rates were compared between the two groups using log-rank tests. Univariate and multivariate Cox regression analyses were performed in the ePTFE group to find predictive factors of poor outcomes. Results: Two groups were homogeneous in terms of preoperative risk factors and morphological data. Median follow-up duration was similar (24 months [interquartile range [IQR], 10-36 months] GSV group vs 21 months [IQR, 7-47 months] ePTFE group; P =.123). At 5 years, there were no differences between the two groups in terms of survival (84.7% GSV group vs 86.1% ePTFE group; P =.097, log-rank = 2.756), secondary patency (94.9% GSV group vs 89.4% ePTFE group; P =.068, log-rank = 3.336), or amputation-free survival (99.1% GSV group vs 99.6% ePTFE group; P =.567, log-rank =.328). Five-year primary patency (89.5% GSV group vs 76.2% ePTFE group; P =.007, log-rank = 7.239) and freedom from reintervention(s) (92.8% GSV group vs 80.6% ePTFE group; P =.011, log-rank = 6.449) were significantly higher in the GSV group. Using multivariate analysis in the ePTFE group, factors compromising primary patency were patients on dialysis (P =.054; odds ratio, 3.641), and patients who were not on any preoperative antiplatelet therapy or anticoagulation (P =.019; odds ratio, 5.532), whereas none of the perioperative factors affected freedom from reintervention(s). Conclusions: GSV as graft guaranteed better primary patency with lower reinterventions rates at midterm follow-up after treatment of PAAs via a posterior approach. Patients on dialysis and who were not on any preoperative antiplatelet therapy or anticoagulation had lower patency rates
Driving ability after conscious sedation: a systematic review
Get PDFIntroduction: Conscious sedation is widely used in medicine but may cause impairment of psychomotor and cognitive function that affect some aspects of a patient's life, such as car driving. This systematic review aims to summarize available evidence (direct or indirect) on driving ability after conscious sedation. Evidence acquisition: A comprehensive search was conducted including MEDLINE/PubMed, EMBASE, SCOPUS, clinicaltrials.gov and the Cochrane Database of Systematic Reviews through June 2022. Randomized and non-randomized controlled trials were included. PRISMA guidelines were followed. Risk of bias was appraised as reported in the Cochrane Handbook for Systematic Reviews of Interventions. Evidence synthesis: A narrative synthesis of 27 studies (962 subjects) was conducted, because the heterogeneity in terms of interventions and comparators, method and timing of assessment, and outcome measures precluded the feasibility of a meaningful meta-analysis. Conscious sedation was associated with different degrees of impairment in driving ability (real car driving, simulated driving, subjective perception), and psychomotor and cognitive functions (body sway, sleepiness, adaptive tracking, critical flicker fusion frequency, reaction/attention skills) at 0.5-10 hours after drug administration. Conclusions: The results obtained from this review should be interpreted as a renewed recommendation to avoid driving after conscious sedation is administered. Yet it is not possible to determine when this ability is recovered, leaving this crucial and essential information to future, well-designed and reproducible research
X-Ray Polarization of the High-synchrotron-peak BL Lacertae Object 1ES 1959+650 during Intermediate and High X-Ray Flux States
No full textWe report the Imaging X-ray Polarimetry Explorer (IXPE) polarimetric and simultaneous multiwavelength observations of the high-energy-peaked BL Lacertae object (HBL) 1ES 1959+650, performed in 2022 October and 2023 August. In 2022 October, IXPE measured an average polarization degree ΠX = 9.4% ± 1.6% and an electric-vector position angle ψX = 53° ± 5°. The polarized X-ray emission can be decomposed into a constant component, plus a rotating component, with the rotation velocity ωEVPA = (−117 ± 12) deg day−1. In 2023 August, during a period of pronounced activity of the source, IXPE measured an average ΠX = 12.4% ± 0.7% and ψX = 20° ± 2°, with evidence (∼0.4% chance probability) for a rapidly rotating component with ωEVPA = 1864 ± 34 deg day−1. These findings suggest the presence of a helical magnetic field in the jet of 1ES 1959+650 or stochastic processes governing the field in turbulent plasma. Our multiwavelength campaigns from radio to X-ray reveal variability in both polarization and flux from optical to X-rays. We interpret the results in terms of a relatively slowly varying component dominating the radio and optical emission, while rapidly variable polarized components dominate the X-ray and provide minor contribution at optical wavelengths. The radio and optical data indicate that on parsec scales the magnetic field is primarily orthogonal to the jet direction. On the contrary, X-ray measurements show a magnetic field almost aligned with the parsec jet direction. Confronting with other IXPE observations, we guess that the magnetic field of HBLs on subparsec scale should be rather unstable, often changing its direction with respect to the Very Long Baseline Array jet
Heidegger e la Cina. Un'analisi filosofica e transculturale
Get PDFLa tesi si articola lungo due principali direttrici: la prima prende in esame il rapporto tra la filosofia di Martin Heidegger e il pensiero daoista, attraverso l'analisi dell'esperienza traduttiva del "Daodejing" condotta da Heidegger stesso e dei numerosi riferimenti alle idee daoiste presenti nelle opere heideggeriane, al fine di indagare se e in che misura esse dischiudano ulteriori orizzonti di senso in relazione alle idee chiave del pensiero heideggeriano. La seconda direttrice prende in esame la traduzione in cinese dell'opera "Introduzione alla metafisica", e in particolare le rese in cinese dei termini chiave del pensiero greco presocratico quali "physis", "logos", "aletheia" a sua volta rielaborate da Heidegger, al fine di indagare se e in che misura esse arricchiscano la riflessione heideggeriana su questi temi
LA REGOLAZIONE CONSOB CINQUANT’ANNI DOPO
No full textThe paper examines the phenomenon of the expansion of Consob's unnamed powers, endorsed by case law. In particular, it takes a position on the expansion of the authority's sphere of influence resulting from the recognition of its exercise of powers not expressly provided by law but justified by its institutional objectives. Therefore, address the issue of the quality of procedural guarantees to highlight their unfitness to be a real and effective compensating factor for the expansion of Consob's regulation
Balancing stability and flexibility in cognitive control and learning: the effects of arousal
No full textThe stability-flexibility balance is crucial for effective cognitive control and learning. Stability, achieved by strengthening relevant processes, supports goal-directed behavior, while flexibility enables adaptation to changing demands. However, these two mechanisms can be in opposition: promoting stability may hinder flexibility, and vice-versa. This thesis uses behavioral and computational analyses to investigate how varying levels of arousal impact this balance across a range of cognitive tasks. Three distinct studies were designed to explore this complex relationship, each focusing on a different aspect of arousal and its effects on cognitive performance. The first study investigated the impact of a combined cognitive and social-evaluative stressor, representing a state of supra-optimal arousal, on working memory and its gating mechanisms, which are considered fundamental to broader cognitive control processes. Using the reference-back paradigm, this study revealed that acute stress selectively impaired working memory stability without significantly affecting flexibility. The second study explored how reward incentives, representing a state of optimal arousal, and switch-frequency expectations modulated performance on a task-switching paradigm. The results indicated that rewards optimized performance by increasing processing speed and enhancing stability, particularly in contexts characterized by low switch frequency. Finally, the third study investigated the impact of sleep restriction, representing a state of suboptimal arousal, on learning and inhibitory control, recognizing the increasingly evident link between learning and control processes. This study demonstrated that sleep restriction impaired learning and adaptation to shifting probabilities, specifically by reducing volatility estimation, while leaving inhibitory control processes largely unaffected. Overall, the findings from these three studies reveal a complex and nuanced relationship between arousal and the stability-flexibility. While acute stress appears to impair stability, rewards enhance it, and sleep restriction primarily affects flexibility. These insights contribute to our understanding of how arousal modulates cognitive control and learning processes