Showing papers by "University of Palermo published in 2022"

Application of the group method of data handling (GMDH) approach for landslide susceptibility zonation using readily available spatial covariates

Abstract: Landslide susceptibility (LS) mapping is an essential tool for landslide risk assessment. This study aimed to provide a new approach with better performance for landslide mapping and adopting readily available variables. In addition, it investigates the capability of a state-of-the-art model developed using the group method of data handling (GMDH) to spatially model LS. Furthermore, hybridized models of GMDH were developed using different metaheuristic algorithms. The study area was the Bonghwa region of South Korea, for which an accurate landslide inventory dataset is available. We considered a total of 13 spatial covariates (altitude, slope, aspect, topographic wetness index, valley depth, plan curvature, profile curvature, distance from fault, distance from river, distance from road, land use, density of forest, and lithology were chosen as independent variables). Two benchmark models—random forest and boosted regression trees—were used to compare their results with the standalone GMDH and hybridized models. We compared model accuracy using the two most robust evaluation metrics, root mean square error (RMSE) and area under the receiver operating characteristic curve (AUROC). The validation results showed that hybridized models outperformed the standalone GMDH model. Moreover, the hybridized GMDH-PSO (AUC = 0.83, RMSE = 0.108), GMDH-IWO (AUC = 0.81, RMSE = 0.111), GMDH-BBO (AUC = 0.8; RMSE = 0.12), and GMDH-ICA (AUC = 0.8; RMSE = 0.117) had a better predictive performance than both RF and BRT. Therefore, the proposed approach could successfully produce landslide susceptibility maps using relatively few readily available variables and can be repeated in data-scarce regions.

Next generation diagnostic algorithm in non-small cell lung cancer predictive molecular pathology: The KWAY Italian multicenter cost evaluation study.

Abstract: Aims The KWAY project aims to investigate the economic sustainability of the up-front NGS technologies adoption in the analysis of clinically relevant molecular alterations in NSCLC patients. Methods The diagnostic workflow and the related sustained costs of five Italian referral centers were assessed in four different evolving scenarios were analyzed. For each scenario, two alternative testing strategies were evaluated: the Maximized Standard strategy and the Maximized NGS strategy. Results For each center, the robustness of obtained results was verified through a deterministic sensitivity analysis, observing the variation of total costs based on a variation of ±20 % of the input parameters and ensuring that results would present a consistent behavior compared to the original ones. Conclusions our project, highlighted that the adoption of NGS allows to save personnel time dedicated to testing activities and to reduce the overall cost of testing per patient.

Synthesis of 2H-Imidazo[2′,1':2,3] [1,3]thiazolo[4,5-e]isoindol-8-yl-phenylureas with promising therapeutic features for the treatment of acute myeloid leukemia (AML) with FLT3/ITD mutations

Abstract: Despite progressive advances in understanding the molecular biology of acute myeloid leukemia (AML), the conventional therapeutic approach has not changed substantially, and the outcome for most patients is poor. Thus, continuous efforts on the discovery of new compounds with improved features are required. Following a multistep sequence, we have identified a new tetracyclic ring system with strong antiproliferative activity towards several haematological cell lines. The new compounds possess structural properties typical of inactive-state-binding kinase inhibitors and are structurally related to quizartinib which is known as type-II tyrosine kinase inhibitor. In particular, the high activity found in two cell lines MOLM-13 and MV4-11, expressing the constitutively activated mutant FLT3/ITD, indicates inhibition of FLT3 kinase and on the basis of structure-activity relationship (SAR) the presence of an ureido moiety demonstrates to play a key role in driving the antiproliferative activity towards these cell lines. Molecular modelling studies supported the mechanism of recognition of the most active compounds within the FLT3 pocket where quizartinib binds. Moreover, Molecular Dynamics simulation (MDs) revealed the formation of a recurrent H-bond with Asp829, which more stabilizes the complex of 9c and the FLT3 inactive state. In MV4-11 cell line compound 9c reduces the phosphorylation of FLT3 (Y591) and some of its downstream targets leading to cell cycle arrest at G1 phase and induction of apoptosis. In an MV4-11 xenograft mouse model, 9c significantly reduces the tumor growth at the dose of 1-3 mg/kg without apparent toxicity.

Hepatectomy Versus Sorafenib in Advanced Nonmetastatic Hepatocellular Carcinoma

Abstract: Objective: The aim of the study was to compare SURG vs SOR regarding the OS and progression-free survival (PFS) in a real-world clinical scenario. Background data: The treatment for advanced nonmetastatic HCC belonging to the Barcelona Clinic Liver Cancer stage C (BCLC C) is still controversial. Methods: BCLC C patients without extrahepatic spread and tumoral invasion of the main portal trunk were considered. Surgical patients were obtained from the HE.RC.O.LE.S. Register, whereas sorafenib patients were obtained from the ITA.LI.CA register The inverse probability weighting (IPW) method was adopted to balance the confounders between the 2 groups. Results: Between 2008 and 2019, 478 patients were enrolled: 303 in SURG and 175 in SOR group. Eastern Cooperative Oncological Group Performance Status (ECOG-PS), presence of cirrhosis, steatosis, Child-Pugh grade, hepatitis B virus and hepatitis C virus, alcohol intake, collateral veins, bilobar disease, localization of the tumor thrombus, number of nodules, alpha-fetoprotein, age, and Charlson Comorbidity index were weighted by IPW to create two balanced pseudo-populations: SURG = 374 and SOR = 263. After IPW, 1–3–5 years OS was 83.6%, 68.1%, 55.9% for SURG, and 42.3%, 17.8%, 12.8% for SOR (P < 0.001). Similar trends were observed after subgrouping patients by ECOG-PS = 0 and ECOG-PS >0, and by the intrahepatic location of portal vein invasion. At Cox regression, sorafenib treatment (hazard ratio 4.436; 95% confidence interval 3.19–6.15; P < 0.001) and Charlson Index (hazard ratio 1.162; 95% confidence interval 1.06–1.27; P = 0.010) were the only independent predictors of mortality. PFS at 1–3–5 years were 65.9%, 40.3%, 24.3% for SURG and 21.6%, 3.5%, 2.9% for SOR (P = 0.007). Conclusions: In BCLC C patients without extrahepatic spread but with intrahepatic portal invasion, liver resection, if feasible, was followed by better OS and PFS compared with sorafenib.

Plastic or not plastic? That’s the problem: analysing the Italian students purchasing behavior of mineral water bottles made with eco-friendly packaging

Abstract: European Strategy for Plastics in a Circular Economy draws new shapes of economy in order to protect the environment and reduce marine pollution, GHGs and countries’ dependence on imported fossil fuels. The core of EU Strategy is also to try to transform the way plastic products are designed, produced, used and recycled in the EU. Italy is the first country in Europe and the second in the world for consumption of bottled water, with remarkable environmental impacts, from production to distribution. Starting from social science theory, this work aims to investigate consumers' behavior and the related factors that influence their behavior pertaining to the purchase of. mineral water bottles made with eco-friendly packaging, taking the student population of the University of Palermo as a reference sample. The work carries out an analysis by means of a fuzzy approach that is based on the evidence that the real world is so complex that it cannot be treated by means of clear rigid propositions. Findings show the presence of high sensitivity to pay for green bottles. This work further contributes to the existing research by emphasizing the crucial role of new marketing and policy plans based on the attitudinal, behavioral and socio-economic characteristics of consumers. Thus, this study delivers insights for policy-makers towards formulating favourable policies to increase sustainable firm processes and consumers’ green consumption within circular models.

Dynamic cerebrovascular autoregulation in patients prone to postural syncope: Comparison of techniques assessing the autoregulation index from spontaneous variability series

Abstract: Three approaches to the assessment of cerebrovascular autoregulation (CA) via the computation of the autoregulation index (ARI) from spontaneous variability of mean arterial pressure (MAP) and mean cerebral blood flow velocity (MCBFV) were applied: 1) a time domain method (TDM); 2) a nonparametric method (nonPM); 3) a parametric method (PM). Performances were tested over matched and surrogate unmatched pairs. Data were analyzed at supine resting (REST) and during the early phase of 60° head-up tilt (TILT) in 13 subjects with previous history of postural syncope (SYNC, age: 28 ± 9 yrs.; 5 males) and 13 control individuals (noSYNC, age: 27 ± 8 yrs.; 5 males). Analysis was completed by computing autonomic markers from heart period (HP) and systolic arterial pressure (SAP) variability series via spectral approach. HP and SAP spectral indexes suggested that noSYNC and SYNC groups exhibited different autonomic responses to TILT. ARI analysis indicated that: i) all methods have a sufficient statistical power to separate matched from unmatched pairs with the exception of nonPM applied to impulse response; ii) ARI estimates derived from different methods might be uncorrelated and, even when correlated, might exhibit a significant bias; iii) orthostatic stressor did not induce any evident ARI change in either noSYNC or SYNC individuals; iv) this conclusion held regardless of the method. Methods for the ARI estimation from spontaneous variability provide different ARIs but none indicate that noSYNC and SYNC subjects have different dynamic component of CA.

Sample building orientation effect on porosity and mechanical properties in Selective Laser Melting of Ti6Al4V titanium alloy

Abstract: In recent decades, the focus of research has shifted towards new production technologies with the aim of optimizing production and reducing costs. These innovative technologies include additive manufacturing processes as Selective Laser Melting (SLM). The analysis of the literature on the identification of optimal building orientation to maximize the mechanical properties and minimize porosity of the final products highlights contrasting results, denoting that the thermomechanical complexity of the process, as associated with the variation of the building orientation, has not been fully clarified. A study in which the building orientation effect was evaluated together with the geometry of the sample and characterized as a function of the preferentially active heat exchange phenomena was carried out with the aim to provide guidelines for the choice of the orientation angle. Heat accumulation phenomena observed in SLM were taken into account to define three geometrical parameters able to identify the causes of the decrease of mechanical properties due to incorrect choice of the orientation angle.

Achieving complete nitrification below the washout SRT with hybrid membrane aerated biofilm reactor (MABR) treating municipal wastewater

Abstract: This study analyzed the performances of a hybrid membrane aerated biofilm reactor (MABR) pilot plant in terms of nutrients removal of the attached growth and suspended biomass in comparison with a conventional activated sludge (CAS) system at different sludge retention time (SRT) (20−3) days. Overall, the MABR showed better performances than the CAS in terms of TSS (86% vs 79%), COD (89% vs 85%) and total nitrogen (80% vs 65%). The minimum SRT for achieving complete nitrification in the MABR was close to 3 days, corresponding to a SRT in the aerobic compartment of 1.9 days, whereas in the CAS it was equal to 8 days (aerobic SRT of 4.8 days). Nitrification rate in biofilm was on average equal to 0.40 gNH 4 -N h −1 (2.40 gNH 4 -N m −2 d −1 ). Its contribution to the overall nitrification in the MABR plant was 25–30% on average, although it increased when the SRT was decreased. Particle size distribution and microscopic analyses showed particles of biofilm detached from the membrane of the MABR. The seeding effect allowed sustaining nitrification of the suspend biomass at very low SRT. The nitrification rate observed in the suspended biomass in the MABR slightly decreased from 3.42 mgNH 4 -N gVSS −1 h −1 to 2.87 mgNH 4 -N gVSS −1 h −1 when the SRT was decreased from 20 days and 3 days, whereas in the CAS it collapsed from 2.33 mgNH 4 -N gVSS −1 h −1 to 0.47 mgNH 4 -N gVSS −1 h −1 , because of nitrifying washout. Moreover, the biofilm detachment involved a positive effect in settling properties of the suspended biomass. • A hybrid MABR pilot plant fed with real wastewater was monitored for 304 days. • High nitrification efficiency was obtained in MABR with aerobic SRT of 1.8 days. • Seeding effect enabled high nitrification in MABR below the washout SRT of CAS. • Biofilm performed stable nitrification rate of 2.40 gNH 4 -N m −2 d −1 regardless of SRT. • Biofilm detachment improved settling properties of the suspended biomass.

The potential of antimicrobial peptides isolated from freshwater crayfish species in new drug development: A review.

Abstract: The much-publicised increased resistance of pathogenic bacteria to conventional antibiotics has focused research effort on the characterization of new antimicrobial drugs. In this context, antimicrobial peptides (AMPs) extracted from animals are considered a promising alternative to conventional antibiotics. In recent years, freshwater crayfish species have emerged as an important source of bioactive compounds. In fact, these invertebrates rely on an innate immune system based on cellular responses and on the production of important effectors in the haemolymph, such as AMPs, which are produced and stored in granules in haemocytes and released after stimulation. These effectors are active against both Gram-positive and Gram-negative bacteria. In this review, we summarise the recent progress on AMPs isolated from the several species of freshwater crayfish and their prospects for future pharmaceutical applications to combat infectious agents.

Identification of Copy Number Variations and Genetic Diversity in Italian Insular Sheep Breeds

Abstract: Copy number variants (CNVs) are one of the major contributors to genetic diversity and phenotypic variation in livestock. The aim of this work is to identify CNVs and perform, for the first time, a CNV-based population genetics analysis with five Italian sheep breeds (Barbaresca, Comisana, Pinzirita, Sarda, and Valle del Belìce). We identified 10,207 CNVs with an average length of 1.81 Mb. The breeds showed similar mean numbers of CNVs, ranging from 20 (Sarda) to 27 (Comisana). A total of 365 CNV regions (CNVRs) were determined. The length of the CNVRs varied among breeds from 2.4 Mb to 124.1 Mb. The highest number of shared CNVRs was between Comisana and Pinzirita, and only one CNVR was shared among all breeds. Our results indicated that segregating CNVs expresses a certain degree of diversity across all breeds. Despite the low/moderate genetic differentiation among breeds, the different approaches used to disclose the genetic relationship showed that the five breeds tend to cluster in distinct groups, similar to the previous studies based on single-nucleotide polymorphism markers. Gene enrichment was described for the 37 CNVRs selected, considering the top 10%. Out of 181 total genes, 67 were uncharacterized loci. Gene Ontology analysis showed that several of these genes are involved in lipid metabolism, immune response, and the olfactory pathway. Our results corroborated previous studies and showed that CNVs represent valuable molecular resources for providing useful information for separating the population and could be further used to explore the function and evolutionary aspect of sheep genome.

An immunologist’s guide to immunosenescence and its treatment

Abstract: Aging causes several changes in the immune system, although immune aging is strongly influenced by individual immunological history, as well as genetic and environmental factors leading to inter-individual variability.We focused on the biological and clinical meaning of immunosenescence. SARS-CoV-2 and Yellow Fever vaccine have demonstrated the clinical relevance of immunosenescence, while inconsistent results, obtained from longitudinal studies aimed at looking for immune risk phenotypes, have revealed that immunosenescence is highly context-dependent. Large projects allowed the delineation of the drivers of immune system variance, including genetic and environmental factors, sex, smoking, and co-habitation. Therefore, it is difficult to identify the interventions that can be envisaged to maintain or improve immune function in older people. That suggests that drug treatment of immunosenescence should require personalized intervention. Regarding this, we discussed the role of changes in lifestyle as a potential therapeutic approach.Our review points out that age is only part of the problem of immunosenescence. Everyone ages differently because is unique in genetics and experience of life and this applies even more to the immune system (immunobiography). Finally, the review shows how appreciable results in the modification of immunosenescence biomarkers can be achieved with lifestyle modification.

Pouring new wine into old bottles: A dynamic perspective of the interplay among environmental dynamism, capabilities development, and performance

Abstract: In order to face increased environmental dynamism (ED), firms are increasingly called on to leverage deliberate learning processes that make dynamic capabilities emerge in a path-dependent way from the conversion of tacit knowledge to explicit knowledge. Moreover, to mitigate the effect that ED can play in eroding a firm’s capabilities and subsequently its performance, managers need to effectively align short- and long-term strategies, which in the literature have been addressed as ‘capability traps’. Although these two processes are strictly interrelated, to date they have been treated in quite an isolated way and usually through the development of linear approaches. To fill this gap, leveraging the knowledge-based view and dynamic capabilities theories, a conceptual system dynamics model was developed in this study to reconstruct the causal intertwined relationships existing between ED, capabilities development, and a firm’s performance. Moreover, by building a stock and flow diagram and simulating different scenarios, it was found that the most effective way to cope with ED is to dedicate efforts in both knowledge stocks’ development and process improvement. The paper thus offers theoretical contributions to each of these three literature streams (i.e., knowledge-based view, dynamic capabilities, and system dynamics) and provides a framework to guide managers and decision-makers into arranging deliberate organisational learning processes and fostering organisational alignment between short- and long-term policies.