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On a class of two-step solvable Leibniz algebras
No full textThis paper studies a class of solvable Leibniz algebras, which is a generalisation of Lie algebras. Specifically, we examine 2-step solvable Leibniz algebras that possess a 2-dimensional abelian derived subalgebra. Leveraging previous findings, we explore the left action vector spaces and establish a lower bound on the dimension of the algebra's center in order to classify such indecomposable solvable Leibniz algebras. The main result states that such a Leibniz algebra either has a dimension at most 7 or is described by a bilinear form
Alternatives to current dark energy models
No full textThe envisioned characteristics of a multi-component, inhomogeneous ``cosmological plasma" model are considered whose heavier visible component consists of ``loaded galaxy clusters". These include the optically observed clusters of galaxies, the characteristic electromagnetic radiation (X-rays) emitting plasmas associated with them, whose mass is larger or comparable to that of the galaxies, and the containing dark matter.
The other visible component consists of the lighter but far more numerous ``field galaxies". A third component is the ``pervading dark matter" in which the visible components are immersed.
On this basis, an energy transport equation, involving a ``dark wind", is proposed for the accelerating expansion energy of the multi-component plasma, rather than a homogeneous, ``dark energy" equation of state. This is in analogy to transport equations based on processes relevant to laboratory and space plasmas that are not in thermal equilibrium and for which equations of state cannot be formulated
DNA Methylation Control over Aging: A Focus on Repetitive Elements
No full textDNA methylation is an epigenetic modification that has been gaining particular attention among researchers in the field of aging and aging-related dis
eases. Specific DNA methylation changes, indeed, characterize aged cells and potentially predict age and lifespan, suggesting that they may play a key role during the aging process. In particular, DNA demethylation of repetitive elements (RE) is a common observation in aging cells and correlates with the increase of transcrip
tion of repeat-derived noncoding RNAs. Demethylation of satellites and loss of suppression of retrotransposons generate genome instability, can increase cell stress and affect cell viability, and also can impact the regulation of genes associated with cell-lineage specificity, thus contributing to neurodegeneration and susceptibility to cancer. In this chapter, we discuss recent work on the DNA methylation dynamics at RE during the aging process outlining the potential roles played during aging. A better understanding of these roles could help in the advancement of approaches to enhance healthy aging and of therapies for aging-related diseases
Serum ferritin as a specific biomarker of anti-MDA5-interstitial lung disease: a multicenter, case–control study in observational and validation datasets
No full textBackground: Serum ferritin has been proposed as biomarker of interstitial lung disease (ILD) in anti-MDA5 dermatomyositis (DM). Nevertheless, no data exist for serum ferritin in other idiopathic inflammatory myopathies (IIM)-ILD nor in IIM without ILD. Aim of this case–control study was to assess whether serum ferritin may be considered a specific and sensitive biomarker for IIM-ILD, as well as to assess whether it correlates with clinical and immunological findings. Patients and methods: All patients affected by IIM and followed at Siena (Italy), Palermo (Italy), Bari (Italy) and Lucknow, (India) IIM referral centers were retrospectively included. They had diagnosis of DM and ASS, with and without ILD. Myositis specific or myositis associated antibodies were tested through line immunoassay (Euroimmune, Lubeck, Germany). Serum ferritin concentrations at the first assessment (T0) were detected by ChemiLuminescent Enzyme Immunoassay technology. Results: A total of 139 IIM patients (study cohort n = 51 and validation cohort n = 88; mean age and standard deviation 44.3 ± 17.75) were included. The most common subtype was DM (n = 70, 50.3%), followed by ASS (n = 50, 35.9%). The three most common MSAs were MDA5 (n = 25, 18%), Jo1 (n = 25, 18%) and Mi2 (n = 10, 7%). ILD was assessed in 69 subjects. Ferritin values were higher in DM-MDA5 than DM-non-MDA5 (p = 0.0073) and ASS (p = 0.0006). All 69 patients affected by ILD were subsequently divided showing statistically significant difference for ferritin (p = 0.0013). Conclusion: Our study included a huge number of patients from multicenter datasets, comprising patients of different ethnicities. Ferritin values lower than 303.5 ng/ml evaluated for the first time in a patient with suspected IIM and ILD, waiting for autoimmunity tests, allowed to exclude MDA5-DM. The strength of our findings was corroborated by binomial logistic regression, which proved the independence of ferritin from CPK and CRP to identify DM-MDA5-ILD. Such evidence allows to exclude that ferritin values are influenced by systemic inflammation
Thermodynamic Evolution of Flaring Loops with Nonlocal Thermal Transport
Get PDFHot solar coronal loops, such as flaring loops, reach temperatures where the thermal transport becomes nonlocal. This occurs when the mean-free-path of electrons can no longer be assumed to be small. Using a modified version of the Lare2d code, we study the evolution of flare-heated coronal loops under three thermal transport models: classical Spitzer–Härm (SH), a flux-limited (FL) local model, and the nonlocal Schurtz–Nicolaï–Busquet (SNB) model. The SNB model is used extensively in laser-plasma studies. It has been benchmarked against accurate nonlocal Vlasov–Fokker–Planck models and proven to be the most accurate nonlocal model that can be applied on fluid timescales. Analysis of the density–temperature evolution cycles near the loop apex reveals a distinct evolutionary path for the SNB model, with higher temperatures and lower densities than local models. During energy deposition, the SNB model produces a more localized and intense temperature peak at the apex due to heat flux suppression, which also reduces chromospheric evaporation and results in lower postflare densities. Extreme-ultraviolet emission synthesis shows that the SNB model yields flare light curves with lower peak amplitudes and smoother decay phases. We also find that nonlocal transport affects equilibrium loop conditions, producing hotter and more rarefied apexes. These findings emphasize the need to account for nonlocal conduction in dynamic solar phenomena and highlight the potential of the SNB model for improving the realism of flare simulations. FL conduction models cannot reproduce the results of nonlocal transport covered by the SNB model
Explicit approximation of the Colebrook-White formula based on the friction Reynolds number
No full textSeveral practical applications require a big number of pipes to be calculated a great many times in a short time. In such cases, an explicit formula for determination of the friction factor of the Darcy-Weisbach formula is advisable for noticeably shortening the computation time, with respect to a trial-and-error solution of the Colebrook-White (C-W) formula. In the present paper, unlike previous studies, an explicit formula is obtained based on the result by Colebrook himself that the deviation, here named δ, between the reciprocals of the square roots of the actual friction factor and that relating to a fully turbulent flow in the same pipe is a function of the friction Reynolds number only, Re*. To this aim, a criterion for better estimating the limit Re* value up to which a transitional regime can occur is also given, a limit value that can differ very much from the usual value 70. The explicit formula was achieved by processing a dataset, consisting of a big number of dyads (Re*, δ) generated over a wide range of relative roughnesses and, for each of the latter, over the Re* range where a transitional regime can occur, the latter range reaching the “new” limits for transitional flow as assumed here. The simple formula gives acceptable accuracy for practical engineering purposes
Potere e decisioni pubbliche: la sfida della democrazia deliberativa. Consultazioni elettroniche e disuguaglianze partecipative territoriali
No full textThis chapter focuses on the relations between power and public decision-making in the context of inclusive decision-making processes using the Web, in particular observing those processes initiated from above, by public administrations or the government. It compares the Italian and British cases in relation to the use of online public consultations through national e-portals and hypothesises possible intersections with forms of deliberative democracy. Despite the fact that top-down e-democracy has shown its limits, we believe that institutional intervention can act as a facilitator for bottom-up forms of e-democracy by supporting and funding active participation processes in hybrid online and on-the-ground deliberative arenas, even in those areas where participation in public decision-making is less widespread. The hypothesis is that instead the most widely used system of public consultation remains that of electronic consultations of individual citizens and organisations already interested in politics, through forms of passive listening
Analysing Traceable and Anonymous Browsing Patterns to Understand Purchase Intent in Online Tourism
No full textNowadays, e-commerce has enabled tourists to plan and purchase holidays more efficiently. Therefore, an efficient service provider needs to gain insight into the behaviour of potential tourists in the pre-purchase phase so as to better target promotions and move customers to purchase. Using clickstream data on the traceable and anonymous users of a tourist accommodation services website, our paper explores their online journey by considering browsing profiles as predictors of purchasing probability. We perform a two-stage analysis: first, identifying browsing profiles by means of a mixture hidden Markov model, and second, investigating purchase probability using a logit model based on users’ website history. We apply this approach to data from Sunweb, a Dutch online holiday provider
Multiplex on-chip immunosensor for advancing inflammation biomarkers monitoring
Get PDFChronic inflammatory diseases significantly impact quality of life and healthcare resources. Continuous monitoring of biomarkers in easily accessible biological fluids presents a promising strategy to enhance management, optimize treatments, and improve patient outcomes. Interleukin-8 (IL-8) is a pro-inflammatory cytokine whose levels increase during chronic airways inflammatory diseases and can be found in human saliva. To this end, electrochemical immunosensors which can effectively detect clinically relevant biomarkers, while also offering the benefits of miniaturization and portability will enable telemedicine applications for remote monitoring and personalized healthcare. In this work, we developed an advanced electrochemical multiplex immunosensor platform using gold micro-electrodes modified by the electrochemical deposition of a gold foam and an antifouling polymeric layer. The sensor capability for multiple detection was evaluated by measuring human interleukin 8 (H-IL8) and human immunoglobulin G (H-IgG) (the latter used as a model analyte). Immunosensors exhibited high sensitivity even in complex biological samples such as human serum and artificial saliva. A very low detection limit of 69.2 fg mL−1 for H-IgG and 87.6 fg mL−1 for H-IL8 in phosphate buffered saline was established. To assess real-world applicability, the immunosensor was used to quantify H-IL8 release from primary human monocyte-derived macrophages stimulated with pro-inflammatory bacterial lipopolysaccharide and the results were successfully compared with ELISA. Furthermore, the sensor performance was also demonstrated in real biological fluids by detecting H-IL8 in spiked human saliva
Sistemi aerei a pilotaggio remoto e responsabilità per danni a terzi o a cose tra rischio, prevenzione e risarcimento
No full textThe essay systematically examines the legal implications arising from the use of Remotely Piloted Aircraft Systems (RPAS), with particular focus on the liability regime for damage caused to third parties or property. The analysis retraces the evolution of European and national legislation, highlighting the shift towards a regulatory model based on risk assessment. It explores the inclusion of drones within the definition of «aircraft» pursuant to Article 743, paragraph 2, of the Italian Navigation Code, and the applicability of the 1952 Rome Convention. The a. proposes a systematic framework for civil liability, questioning the adequacy of traditional fault-based models in light of the operational autonomy granted to drones equipped with artificial intelligence, and suggesting attribution criteria consistent with technological innovation. The study concludes by advocating for a harmonised and dynamic regulatory framework, oriented towards the effective protection of fundamental rights