Archivio istituzionale della ricerca - Alma Mater Studiorum Università di Bologna
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MacroSwarm: A scala framework for swarm programming
Full text linkProgramming swarm behaviors is a challenging task, due to the need to express collective behaviors in terms of local interactions among simple agents. Even if several programming frameworks have been proposed, they are often based on low-level abstractions, which makes the development of swarm applications complex and error-prone. Thus, we present MacroSwarm, an aggregate programming framework for the development of swarm behaviors. With this framework, it is possible to define a large variety of swarm behaviors, starting from simple movements to more complex ones, such as aggregation, flocking, and collective decision-making. In this paper, we present the main features of the framework and some simple examples of its API usage
Effects of Glucagon-Like Peptide-1 Receptor Agonists on Upper Gastrointestinal Endoscopy: A Meta-Analysis
Full text linkBackground and aims: Limited evidence exists regarding the impact of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on upper endoscopy. Therefore, a meta-analysis was conducted to comprehensively review the available evidence on this subject. Methods: A systematic bibliographic search was carried out until May 2024. Pooled estimates were analyzed using a random-effects model, with results presented as odds ratios (OR) and 95% confidence intervals (CI). The primary outcome assessed was the rate of retained gastric content (RGC), while secondary outcomes included rates of aborted and repeated procedures, adverse event (AE) rate, and rates of aspiration. Results: This analysis included 13 studies involving a total of 84,065 patients. Patients receiving GLP-1RA therapy exhibited significantly higher rates of RGC (OR 5.56, 3.35-9.23), a trend that was consistent among patients with diabetes (OR 2.60, 2.23-3.02). Adjusted analysis, accounting for variables such as sex, age, body mass index (BMI), diabetes, and other therapies, confirmed the elevated rates of RGC in the GLP-1RA user group (aOR 4.20, 3.42-5.15). Furthermore, rates of aborted and repeated procedures were higher in the GLP-1RA user group (OR 5.13, 3.01-8.75, and OR 2.19, 1.43-3.35; respectively). However, no significant differences were found in AE and aspiration rates between the two groups (OR 4.04, 0.63-26.03, and OR 1.75, 0.64-4.77; respectively). Conclusion: Use of GLP-1RAs is associated with increased retention of gastric contents and more frequent aborted procedures during upper endoscopy. However, the AEs and aspiration rates do not seem different, therefore adjusting fasting time instead of routinely withholding GLP-1RAs could be reasonable in these patients
Comprehensive modelling strategy for gas transport in polymers: Analysis of swelling and non-swelling agents at high pressures
No full textGas transport in polymers is a process governed by the interplay between polymeric structure, gas properties, and operating conditions. This work analyzes the solubility and transport properties of different gases in five different industrially relevant polymeric systems, such as Matrimid/P84 polyimide blends, perfluorosulfonic acid membrane (PFSA) Nafion, as well as natural rubber (NR), silicone rubber (PDMS) and a fluorinated rubber (FKM), using a thermodynamic modeling framework, with focus on high-pressure conditions. Specifically, equations of state (EoS) and non-equilibrium thermodynamic for glassy polymers (NET-GP) approaches are able to describe gas solubility, and are combined to the Standard Transport Model (STM) to estimate diffusivity and permeability at various temperatures and pressures, with emphasis on the comparison of swelling and non-swelling penetrants, free-volume variations, and plasticization phenomena. The results obtained reveal the ability of the models to describe the complex experimental behaviors, including challenging systems, such as glassy polymer blends or PFSA membranes. A thorough analysis of the gas transport and sorption properties in the different systems with the penetrant characteristics and with the polymer response to sorption is then performed to elucidate the prevailing effect shaping the behavior of the various systems. Therefore, the model proved to be a powerful tool to inspect the high-pressure induced changes in gas transport, and to predict the solubility and permeability properties in a wide range of conditions
Access to cyclobutane–fused dihydrobenzothiophenes via gold–mediated photocatalyzed [2+2]–cycloaddition reactions
No full textThe use of [Au(SIPr)(Cbz)] as photosensitizer in [2+2]–cycloaddition reactions between benzothiophenes and activated and non–activated alkenes is presented. Commonly used organic and Ir–photosensitizers proved inefficient in the reaction with non–activated alkenes. The study emphasizes the dependence on the nature of the alkene, a parameter that has previously received little attention. Under mild reaction conditions, a wide array of alkenes and benzothiophenes were successfully coupled, showcasing remarkable tolerance of diverse functional groups. Additionally, we present intramolecular [2+2]–cycloaddition reactions, including benzothiophenes featuring various alkene linkers at the C2 and C3 positions
Physical, Mechanical, and Thermal Characterization of the Elastomer Response to High-Pressure CO2 for Use in Carbon Capture and Storage Applications
No full textCO2 transport efficiency is vital for the success of carbon capture, utilization,and storage (CCUS) which is considered one of the most viable solutions to limit CO2release in the atmosphere, aiming to reach net-zero CO2 emissions. To increase transportefficiency, CO2 must be compressed and transported as a liquid or supercritical fluid,conditions that might affect the performance of the materials employed. In fact, polymersmay absorb CO2 molecules during their handling via pipelines and ships and this can lead toplasticization and the risk of rapid gas decompression (RGD) damage when the CO2 pressureis released. In this concern, elastomers comprise only a small portion of the CCS value chainbecause they are mainly used as seals and gaskets; however, they are essential elements forcontrolling leakage. This work presents the results of a comprehensive experimentalcharacterization of high-pressure CO2 compatibility in common elastomers, such as ethylenepropylene diene monomer (EPDM), natural rubber (NR), and butyl rubber (IIR), viathermal, mechanical, and transient-sorption experiments. From the results obtained, we sawthat CO2 solubility is always lower than 0.09 gCO2/gpol for all materials, while permeabilityreaches values higher that 100 Barrer at 45 °C for EPDM and NR. The role of reinforcing fillers incorporated into the polymermatrix has been also analyzed with a focus on evaluating their influence on mechanical properties and CO2 transport properties. Inthis concern, swelling decreases from 400 to 70% from NR to EPDM, as the filler content increases, suggesting a positive interactionbetween the two phases. The extent of the analysis has been then upgraded by performing a modeling description of the resultsthrough the use of a thermodynamic equation of state (EoS) approach, thanks to which the polymer−penetrant interaction can bepredicted in a wider range of pressure and temperature, down to cryogenic environments, as the one required for the CCS transport chain
Systemic Scytalidium Infection with Hyperbetaglobulinemia in a Giant Schnauzer
No full textScytalidiosis in humans primarily causes feet and nail infections, with systemic infections rarely reported. In dogs, only one systemic infection of Scytalidium spp. has been reported to date. A 3-year-old giant schnauzer presented with loss of appetite, lethargy, and hind limb lameness. A complete clinical examination was performed, along with hematobiochemical tests, radiography, CT, MRI, and cytological and microbiological analyses of it enlarged lymph nodes. Hyperglobulinemia, vertebral osteolysis, and generalized lymphadenomegaly were diagnosed. Cytopathological and molecular investigations confirmed Scytalidium. Although treated with itraconazole, the dog's condition worsened after a premature discontinuation of therapy, leading to euthanasia. A post-mortem and histopathological examination revealed widespread infection. This case highlights the need to consider fungal infections in cases of elevated beta-2 protein
Study of WH production through vector boson scattering and extraction of the relative sign of the W and Z couplings to the Higgs boson in proton-proton collisions at √ s =13 Te V
No full textA search for the production of a W boson and a Higgs boson through vector boson scattering (VBS) is presented, using CMS data from proton-proton collisions at √s=13TeV collected from 2016 to 2018. The integrated luminosity of the data sample is 138fb−1. Selected events must be consistent with the presence of two jets originating from VBS, the leptonic decay of the W boson to an electron or muon, possibly also through an intermediate τ lepton, and a Higgs boson decaying into a pair of b quarks, reconstructed as either a single merged jet or two resolved jets. A measurement of the process as predicted by the standard model (SM) is performed alongside a study of beyond-the-SM (BSM) scenarios. The SM analysis sets an observed (expected) 95% confidence level upper limit of 14.3 (9.9) on the ratio of the measured VBS WH cross section to that expected by the SM. The BSM analysis, conducted within the so-called κ framework, excludes all scenarios with λWZ<0 that are consistent with current measurements, where λWZ=κW/κZ and κW and κZ are the HWW and HZZ coupling modifiers, respectively. The significance of the exclusion is beyond 5 standard deviations, and it is consistent with the SM expectation of λWZ=1
Mastering palladium-catalyzed cross-coupling reactions: the critical role of in situ pre-catalyst reduction design
No full textPalladium-catalyzed cross-coupling reactions are among the most used methods for carbon–carbon
bond formation in the agrochemical and pharmaceutical segments. The key step common to all methodologies based on Pd(0) catalysis is the in situ generation of the active catalyst. This paper describes how to
control pre-catalyst reduction in order to generate the target complex species while avoiding phosphine
oxidation or, as in the case of the Heck–Cassar–Sonogashira and the Suzuki–Miyaura reactions, reactant
consumption via dimerization. For PPh3, DPPF, DPPP, Xantphos, SPhos, RuPhos, XPhos and sSPhos, we
identified protocols that are able to maximize reduction via alcohols while preserving ligands and
reagents. The correct combination of counterion, ligand, and base allowed the perfect control of the Pd
(II) reduction to Pd(0) in the presence of primary alcohol
Travaux manuels
No full textSi tratta di un saggio sul lavoro manuale nei conventi tra XIX e XX secol
Singular limit of BSDES and optimal control of two scale systems with jumps in infinite dimensional spaces
Full text linkThe paper is devoted to a stochastic optimal control problem for a two scale,
infinite dimensional, stochastc system. The state of the system consists of “slow” and “fast”
component and its evolution is driven by both continuous Wiener noises and discontinuous
Poissonn-type noises. The presence of discontinuous noises is the main feature of the
present work. We use the theory of backward stochastic differential equations (BSDEs) to
prove that, as the speed of the fast component diverges, the value function of the control
problem converges to the solution of a reduced forward backward system that, in turn,
is related to a reduced, stochastic, optimal control problem. The results of this paper
generalize to the case of discontinuous noise the ones in [18] and [24]