University of Udine
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Fogli di carta: misure e provenienze
No full textAnalisi della carta e delle filigrane nel catalogo degli incunaboli
Heat treatments for the control of postharvest decay of fresh fruit: case studies of peach brown rot, kiwifruit gray mold and citrus green and blue molds
Full text linkModeling the quality decay kinetic of encapsulated ground coffee
Full text linkA fully predictive model for quality decay kinetic of ground coffee packaged in bioplastics is not available today. Therefore, a new model is proposed to predict the kinetics of quality decay of encapsulated ground coffee (indicated as EGC), stored under constant temperature and relative humidity conditions. The proposed model assumed that a first-order type equation, with a kinetic constant dependent on water activity, can be used to describe the quality decay of EGC. To predict the variation of water activity inside the capsule over time, the mass balance of the water inside the capsule was carried out. Specific tests were conducted at 23 °C to estimate the model's parameters. Tests on ground coffee were run to estimate the parameters used to relate the kinetic constant to the water activity; the capsule filled with silica gel was used to determine the dependence of water permeability coefficient on the water activity inside and outside the capsule. The ground coffee water sorption isotherm at 23 °C was also determined. The quality decay kinetic of EGC was measured by monitoring the pH as reliable quality descriptor and it was used to assess the goodness of the model prediction. Results indicated that notwithstanding the numerous assumptions made to derive the new model, its ability to predict the quality decay kinetic of EGC is quite acceptable
A tidal volume of 7 mL/kg PBW or higher may be safe for COVID-19 patients
No full textPurpose: The novel coronavirus disease (COVID-19) has revived the debate on the optimal tidal volume during acute respiratory distress syndrome (ARDS). Some experts recommend 6 mL/kg of predicted body weight (PBW) for all patients, while others suggest 7–9 mL/kg PBW for those with compliance >50 mL/cmH2O. We investigated whether a tidal volume ≥ 7 ml/kg PBW may be safe in COVID-19 patients, particularly those with compliance >50 mL/cmH2O. Materials and methods: This secondary analysis of a multicenter study compares the Intensive Care Unit (ICU) mortality among 600 patients ventilated with 50 mL/cmH2O. Results: 346 patients were ventilated with <7 (6.2 ± 0.5) mL/kg PBW and 254 with ≥7 (7.9 ± 0.9) mL/kg PBW. ICU mortality was 33 % and 29 % in the two groups (p = 0.272). At multivariable regression analysis, tidal volume ≥ 7 mL/kg PBW was associated with lower ICU mortality in the overall population (odds ratio: 0.62 [95 %-confidence interval: 0.40–0.95]) and in each compliance category. Conclusions: A tidal volume ≥ 7 (up to 9) mL/kg PBW was associated with lower ICU mortality in these COVID-19 patients, including those with compliance <40 mL/cmH2O. This finding should be interpreted cautiously due to the retrospective study design. Trial registration: ClinicalTrails.gov NCT04388670
Detection of the Geminga pulsar at energies down to 20 GeV with the LST-1 of CTAO
Full text linkContext. Geminga is the third gamma-ray pulsar firmly detected by imaging atmospheric Cherenkov telescopes (IACTs) after the Crab and the Vela pulsars. Most of its emission is expected at tens of giga-electronvolts, and, out of the planned telescopes of the upcoming Cherenkov Telescope Array Observatory (CTAO), the Large-Sized Telescopes (LSTs) are the only ones with optimised sensitivity at these energies. Aims. We aim to characterise the gamma-ray pulse shape and spectrum of Geminga as observed by the first LST (hereafter LST-1) of the Northern Array of CTAO. Furthermore, this study confirms the great performance and the improved energy threshold of the telescope, as low as 10 GeV for pulsar analysis, with respect to current-generation Cherenkov telescopes. Methods. We analysed 60 hours of good-quality data taken by the LST-1 between December 2022 and March 2024 at zenith angles below 50◦. Additionally, a new Fermi-LAT analysis of 16.6 years of data was carried out to extend the spectral analysis down to 100 MeV. Lastly, a detailed study of the systematic effects was performed. Results. We report the detection of Geminga in the energy range between 20 and 65 GeV. Of the two peaks of the phaseogram, the second one, P2, is detected with a significance of 12.2σ, while the first (P1) reaches a significance level of 2.6σ. The best-fit model for the spectrum of P2 was found to be a power law with a spectral index of Γ = (4.5±0.4stat)−+0062syssys, compatible with the previous results obtained by the MAGIC Collaboration. No evidence of curvature is found in the LST-1 energy range. The joint fit with Fermi-LAT data confirms a preference for a sub-exponential cut-off over a pure exponential, even though both models fail to reproduce the data above several tens of giga-electronvolts. The overall results presented in this paper prove that the LST-1 is an excellent telescope for the observation of pulsars, and improved sensitivity is expected to be achieved with the full CTAO Northern Array
30 anni di AISCOM: Il mosaico medievale
No full textSi ripercorrono trent'anni di contributi di ambito paleocristiano e medievale nei colloqui AISCOM evidenziando l'importanza innovativa dei contributi per la ricerca sui mosaici pavimentali medievali, e sottolineando l'importanza dei Colloqui, divenuti punto di riferimento imprescindibile per chi si occupa di questo ambito di studi
The Magnitude of Truth: On Using Magnitude Estimation for Truthfulness Assessment
Full text linkEvaluating the truthfulness of online content is critical for combating misinformation. This study examines the efficiency and effectiveness of crowdsourced truthfulness assessments through a comparative analysis of two approaches: one involving full-length webpages as evidence for each claim, and another using summaries for each evidence document generated with an LLM. Using an A/B testing setting, we engage a diverse pool of participants tasked with evaluating the truthfulness of statements under these conditions.Our analysis explores both the quality of assessments and the behavioral patterns of participants. The results reveal that relying on summarized evidence offers comparable accuracy and error metrics to the standard modality while significantly improving efficiency. Workers in the Summary setting complete a significantly higher number of assessments, reducing task duration and costs. Additionally, the Summary modality maximizes internal agreement and maintains consistent reliance on and perceived usefulness of evidence, demonstrating its potential to streamline large-scale truthfulness evaluations
Model Free Estimation of Causal Effects of Different Stimuli on Neuron Activities
No full textSeveral activities and functions of neurons are determined by intracellular signals generated by calcium ions, with calcium levels rapidly increasing during neuronal activity. Technological advances in calcium imaging techniques have allowed a large amount of data to be collected to study brain behavior at the neuronal level. We investigate the effects of different sensory stimuli on neuronal activity in the visual cortex of mice. The novel contribution of this work is the investigation of the relationship between visual stimuli and calcium concentration levels in terms of causal effects. Estimation and inference are carried out in a potential outcomes framework, where the dynamic behavior of calcium traces is managed by borrowing tools from the randomized experiments literature. Results show significant causal effects on the neuronal activity due to the smoothness and geometry of the stimuli
Preoperative Mechanical Ventilation Prior to Surgical Repair for Type A Aortic Dissection: Incidence, Risk, and Outcomes
Full text linkObjectives: Several conditions associated with type A aortic dissection may require preoperative invasive mechanical ventilation (IMV). The current literature lacks data on this subset of patients’ prevalence and postoperative outcomes. This study aims to investigate this unexplored issue in a multicenter European registry. Methods: Data from 3735 patients included in the European Registry of Type A Aortic Dissection (ERTAAD) were the subject of this analysis. Bootstrapped Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression was performed for variable selection to identify key predictors of hospital death. In the second step, a multilevel multivariable logistic regression (MMLR) was carried out, given the clustered structure of the data. Results: A total of 346 (9.3%) out of 3735 patients required preoperative IMV. Compared to the non-IMV patients, patients requiring IMV had a significantly higher rate of organ malperfusion (52% vs. 35%, p < 0.001) and a higher proportion of tears in the aortic root (p = 0.048). The in-hospital mortality rate among IMV patients was 38% vs. 15% in non-IMV patients (p < 0.001), without a difference in post-discharge survival (p = 0.84). At the MMLR, patients who required IMV had 135% higher odds of in-hospital death compared to the remaining patients. IMV yielded the second highest odds in the prediction model for in-hospital mortality (OR 2.13, CI 1.60 to 2.85, p < 0.001). Among IMV patients, the extension of surgery to the aortic arch was significantly associated with increased in-hospital mortality (p < 0.001, OR 2.98). In multivariable analysis, preoperative IMV was independently associated with increased odds of in-hospital mortality. Conclusions: The need for invasive mechanical ventilation before surgical repair for type A aortic dissection is not infrequent. In this subpopulation, the in-hospital mortality rate was twofold compared to patients who did not require IMV. The awareness of the preoperative risk profile and outcomes of this subset of patients should urge surgeons to tailor the surgical strategy more appropriately to improve the immediate postoperative results
Innovazione sostenibile per migliorare la qualità dei prodotti carnei nell'era del Green Deal
No full textThis Ph. D. thesis is focused on the implementation of meat product quality. In recent years the European Union has promoted a "green" policy for the research of new, more sustainable technologies with the aim of achieving carbon neutrality by 2050. In particular, an issue that is very important to consumers is the reduction of the use of synthetic preservatives, favouring the use of natural compounds. Among synthetic preservatives, the most used for the preparation of fermented meat products are nitrite and nitrate salts. Despite a long history of use, the consumption of nitrites has been associated with stomach cancer, being that nitrite residues in an acidic environment can react with protein residues and form N-nitroso-compounds, a class of compounds in which carcinogenic molecules are also included. Considering that fermented meat products have always been part of the Italian culinary tradition, improving quality is a central issue to protect consumer health without excluding traditional meat products from the diet. In this regard, lactic acid bacteria and coagulase negative catalase positve cocci have been investigated for their ability to produce nitric oxide via nitric oxide synthase pathway in order to reduce the use of nitrite and nitrates in fermented meat products. The most promising strains have been selected for the production of fermented sausages. Microbial safety, chemical-physical quality and sensory properties of innovative products have been investigated. Results indicate that a partial remove of nitrite and nitrate in fermented meat products is possible and that the selection of performing strains is a valid strategy to improve the quality of meat products