IRIS Università degli Studi dell'Aquila
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Coupling biomass hydrothermal carbonization and green solvent extraction
Get PDFThis paper merges two leading-edge practices of sustainable waste valorization chains – biomass hydrothermal carbonization (HTC) and green solvent extraction – into an integrated process scheme. The innovation is to intersperse two hydrothermal carbonization steps with solvent extraction to recover valuable products from the reaction process water before completing the carbonization. The study uses rice husk as the waste biomass, hydrophobic deep eutectic decanoic acid/thymol (DES) as the green solvent, and furfural and 5-hydroxymethylfurfural as the target chemicals. HTC went batch-wise (230 °C, 1/4 solid/liquid ratio, total reaction time 2 h). DES extraction recovered up to 91 % of the chemicals from the process water. Although only 2 % of the original biomass converts to platform chemicals, the process illustrates a new methodology that is tailorable for other optimized productions. A flowsheet scheme helps quantify mass balances. The many degrees of freedom in the operational parameters allow for the intensification of the industrial-scale process. The new method paves the way for further developments, applying the combined process to other biomasses, solvents, and target chemicals
Batch Heterogeneous Catalytic Selective Hydrogenation of Vegetable Oils Over Lindlar Catalyst: Kinetic Modeling Supported by Reaction Mechanisms
Get PDFHeterogeneous catalytic selective hydrogenation (HCSH) of vegetable oils is a reactive pathway to maximize the fraction of monounsaturated oleic acid, a component of industrial interest, thanks to its stability and low-temperature properties. Kinetics of HCSH is usually interpreted by pseudo-first order laws, as previously done by this research group with data from batch tests on canola oil (Lindlar catalyst, 120-180 °C, 0.4-1.2 MPa): the pseudo-first order kinetics could interpret the observed phenomenon only by variable selectivities (i.e., ratios of kinetic constants). The present work proposes a refined modeling by Hougen-Watson approach. Detailed reaction mechanisms were hypothesized, challenging the following alternatives: (i) H2 adsorption on the catalyst occurred (Hinshelwood-Langmuir) or not (Eley-Rideal), (ii) H2 adsorption was molecular or dissociative, (iii) H2 adsorption was competitive or not with fatty acids adsorption, and (iv) reaction intermediates were formed or not. Six reaction mechanisms were developed with related kinetic rate laws for HCSH. Their kinetic parameters were regressed for the abovementioned experimental data by a purposely developed MATLAB script. The best mechanism was chosen based on the highest explained variance ( R2 ) and the lowest number of parameters. Chemical-physical meaningfulness of regressed parameters for the best model was checked by comparison with the literature
Real-World Analysis of Short-Term Effectiveness of Oral Semaglutide: Impact on Glycometabolic Control and Cardiovascular Risk
Get PDFBackground: Oral semaglutide, a GLP1-receptor agonist (GLP1-RA), shows promise in efficacy and compliance, especially amid the global shortage of injectable GLP-1 RAs. Its short-term effectiveness remains unexplored. Objective: This real-world observational study assessed the short-term effectiveness of oral semaglutide after three months of therapy. Methods: Patients with type 2 diabetes from four Italian diabetes centers, who received an initial prescription of oral semaglutide, were reassessed after three months. Primary outcomes included glycated hemoglobin (HbA1c) and body weight reduction; secondary outcomes involved changes in lipid parameters and cardiovascular risk. Results: Among 167 participants (mean age 66.5 years, mostly obese, baseline HbA1c 8.4% ± 1.5), 83.2% received a 7 mg dose. After three months, HbA1c significantly declined (8.4% to 7.1%, −1.3%, p < 0.001), alongside body mass index (BMI) (30.9 kg/m2 to 29.6 kg/m2, p < 0.0001). The target HbA1c ≤ 7% was achieved by 54.5%, and 34.7% reached ≤6.5%. Patients losing >5% of their initial weight (30.5%) saw the largest HbA1c drop (−1.9%). Those with newly diagnosed diabetes or a duration < 5 years showed superior responses (p = 0.001), while no significant differences were found based on the timing of drug administration. Oral semaglutide replaced or supplemented prior therapies, allowing discontinuation of dipeptidyl peptidase 4 inhibitors (DPP4i), sulfonylureas, glinides, and acarbose, and deprescription of thiazolidinediones. A significant reduction in cardiovascular risk was observed (p = 0.04), together with a significant reduction in lipid parameters. Conclusions: Oral semaglutide showed significant short-term efficacy, reducing HbA1c, body weight, and cardiovascular risk in three months, making it a valuable therapeutic option
A system of continuity equations with nonlocal interactions of Morse type
No full textWe study a system of two continuity equations with nonlocal velocity fields using interaction potentials of both attractive and repulsive Morse type. Such a system is of interest in many contexts in multi-population modeling. We prove the existence, uniqueness and stability in the 2-Wasserstein spaces of probability measures via Jordan-Kinderlehrer-Otto scheme and gradient flow solutions in the spirit of the Ambrosio-Gigli-Savaré theory. We then formulate a deterministic particle scheme for this model and prove that gradient flow solutions are obtained in the many particle limit by discrete densities constructed out of moving particles satisfying a suitable system of ODEs. The ODE system is formulated in a non standard way in order to bypass the Lipschitz singularity of the kernel, with difference quotients of the kernel replacing its derivative
Temporal dynamics of early inflammatory markers after professional dental cleaning: a meta-analysis and spline-based meta-regression of TNF-α, IL-1β, IL-6, and (hs)CRP
Get PDFIntroduction: Chronic periodontitis is linked to systemic inflammation and cardiovascular risk, yet the temporal trajectory and magnitude of systemic cytokine reduction following nonsurgical-periodontal-therapy (NSPT) remain underexplored. We conducted a meta-analysis and spline-based meta-regression to assess whether intensive NSPT, compared to standard therapy, produces sustained reductions in circulating TNF-α, IL-1β, IL-6 and high-sensitivity C-reactive protein (hs-CRP). Methods: We systematically searched major databases for interventional studies published until January 2024 comparing intensive vs. standard NSPT on inflammatory markers. Using a custom R pipeline, standardized mean differences (SMDs), 95% confidence intervals (Cis) heterogeneity (I2) and stratified analyses by phenotype (e.g., smoking, diabetes) and time were performed. A spline-based mixed-effects meta-regression explored temporal dynamics of inflammatory reduction in the intensive group. Results: From 216 observations (14,374 paired values), intensive NSPT led to significantly greater reductions in TNF-α (SMD –0.59, 95% CI –1.02 to –0.16; P=0.008), IL-6 (SMD –0.20, 95% CI –0.39 to –0.00; P=0.046) and hs-CRP (SMD –1.17, 95% CI –2.18 to –0.16; P=0.024) compared to standard therapy. IL-1β showed a near-significant reduction (SMD –4.14, P=0.052). Standard therapy was paradoxically associated with greater CRP reduction (SMD –0.30, P=0.001). Age, tooth count and year of publication moderated effects. Early benefits emerged within 3 months for TNF-α and 6 months for IL-1β. Although no strong nonlinear time-response was confirmed (QM = 4.23, P=0.2372),a potential rebound in cytokine suppression was suggested. The overall anti-inflammatory effect remained significant. Discussion: Intensive NSPT reduces systemic inflammation particularly in younger, non-smoking individuals. The potential rebound in inflammatory markers underscores the need for longitudinal studies but, supports the systemic immunoregulatory effect of periodontal therapy. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO, identifier CDR42024503063
Cities Transition Towards Carbon Neutrality: A Review
No full textIn line with the global agreements and the
European Climate Directive, to deal with the climate change and
move towards reducing consumptions of built environment, the
imperative is to achieve a 65% reduction in greenhouse gas
emissions by 2030 and decarbonisation by 2050. However, the
achievement of these targets is still far off, and there is a lack of
systematised operational tools regarding the interventions on
the built environment. This paper presents a review of the state
of the art on the topic of the application of carbon neutrality
strategy in cities management. It highlights the lack of shared
models and strategies to pursue sustainability goals, especially
in post-disaster or post-war reconstruction processes. To this
end, clear guidelines need to be drawn up, including the use of
indicators and the creation of local governance structures that
include citizen participation
Dov'è la letteratura? Circolazione, istituzioni, rapporti di forza
No full textGiocando sulla metafora spaziale, i saggi contenuti all’interno di questo volume si chiedono dov’è la letteratura. In quali circuiti, canali, supporti, dispositivi, forme di esposizione, valorizzazione e patrimonializzazione si produce e si diffonde un fenomeno che continuiamo a chiamare «letterario»? Fino a che punto agiscono ancora i meccanismi tradizionali della consacrazione estetica, fino a che punto tutto è inglobato da quella generale messa a profitto, da quella pervasiva capitalizzazione dell’esperienza che governa la nostra forma di vita? Esiste ancora una «Repubblica mondiale delle lettere»? O forse, il modello politico della Repubblica che ha accompagnato l’avventura della modernità ha ormai ceduto il passo al dispositivo di governo delle attuali tecnocrazie, la Governance? La nozione di “rapporti di forza” risulta ulteriormente estesa alla luce delle recenti logiche di un campo letterario globalizzato, delle nuove relazioni tra il globale e il locale, delle modalità di circolazione, degli inediti canali di consacrazione aperti dalla rete, della mediatizzazione della letteratura, degli assetti linguistici e geo-politici degli anni Duemila, che investono tanto la produzione contemporanea quanto la persistenza o l’eclissi della letteratura già canonizzata, e che dunque modellano anche la storia letteraria e le sue partizioni interne (generi, modelli, canoni, letteratura “alta” e “bassa”, sperimentazione e mainstream)
