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This study investigated chemical composition, cytotoxicity in normal and cancer cells, and antimicrobial and antioxidant activity of the essential oil (EO) isolated by hydrodistillation from the discarded leaves of lemon (Citrus limon) plants cultivated in Sardinia (Italy). The volatile chemical composition of lemon leaf EO (LLEO) was analyzed with gas chromatography-mass spectrometry combined with flame ionization detection (GC/MS and GC/FID). The most abundant component of LLEO was limonene (260.7 mg/mL), followed by geranial (102.6 mg/mL) and neral (88.3 mg/mL). The antimicrobial activity of LLEO was tested using eight bacterial strains and two types of yeasts by a microdilution broth test. Candida albicans showed the greatest susceptibility (MIC = 0.625 μL/mL) and Listeria monocytogenes and Staphylococcus aureus were inhibited at low LLEO concentration (MIC values from 2.5 to 5 μL/mL). The C. limon leaf EO displayed radical scavenging ability (IC50 value of 10.24 mg/mL) in the 2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) assay. Furthermore, the LLEO impact on cell viability was explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in cancer HeLa cells, A375 melanoma cell line, normal fibroblasts (3T3 cells), and keratinocytes (HaCaT cells). LLEO, at 24 h of incubation, significantly reduced viability from 25 μM in Hela cells (33% reduction) and A375 cells (27%), greatly affecting cell morphology, whereas this effect was found from 50 μM on 3T3 fibroblasts and keratinocytes. LLEO’s pro-oxidant effect was also established in HeLa cells by 2′,7′-dichlorodihydrofluorescein diacetate assay.

We consider the virtual element discretization of the Navier–Stokes equations coupled with the heat equation where the viscosity depends on the temperature. We present the virtual element discretization of the coupled problem, show its well-posedness and prove optimal error estimates. Numerical experiments that confirm the theoretical error bounds are also presented.

We discuss the p - and h p -versions of the virtual element method for the approximation of eigenpairs of elliptic operators with a potential term on polygonal meshes. An application of this model is provided by the Schrodinger equation with a pseudo-potential term. As an interesting byproduct, we present for the first time in literature an explicit construction of the stabilization of the mass matrix. We present in detail the analysis of the p -version of the method, proving exponential convergence in the case of analytic eigenfunctions. The theoretical results are supplied with a wide set of experiments. We also show numerically that, in the case of eigenfunctions with finite Sobolev regularity, an exponential approximation of the eigenvalues in terms of the cubic root of the number of degrees of freedom can be obtained by employing h p -refinements. Importantly, the geometric flexibility of polygonal meshes is exploited in the construction of the h p -spaces.

The association between postoperative serum hyperamylasaemia (POH) and morbidity has been hypothesized but rarely explored once occurring with or without (POH-exclusive) a combined postoperative pancreatic fistula (POPF).Analysis of patients who consecutively underwent pancreaticoduodenectomy from 2016 to 2020. POH was defined as serum amylase activity greater than the institutional upper limit of normal (52 U/L), persisting within the first 48 hours postoperatively (postoperative day [POD] 1 and 2).Among 852 patients, 15.8% developed POH-exclusive. Compared with patients without POH or POPF (64.3%), they showed a significantly higher postoperative burden (Clavien-Dindo ≥II: 52.6% vs 30.8%) with increased rates of bacteraemia (12.6% vs 6%), pleural effusion (13.3% vs 5.3%), postpancreatectomy haemorrhage (13.3% vs 7.5%), postpancreatectomy acute pancreatitis (PPAP) (10.3% vs 0%), and organ site infections (18.5% vs 10.9%; all P.05). A total of 13.8% experienced POH with POPF leading to the worse outcome. The combined occurrence of POH with POPF led to a shorter median time to morbidity (3 PODs, 95% confidence interval [CI] 2.2-3.7 vs 6 PODs, 95% CI 4.2-8; P.001) than patients experiencing POPF-exclusive (5.9%). In all, 46.6% of POH patients developed POPF. Body mass index (BMI) (odds ratio [OR] 1.1), male sex (OR 2.1), increased drain fluid amylase on POD 1 (OR 1.001), and increased C-reactive protein (OR 1.01) were independent risk factors for POPF once POH has occurred.POH has relevant postoperative clinical implications, independently from POPF occurrence. Developing POH with POPF leads to an earlier onset of higher postoperative burdens. Once POH is diagnosed, risk factors for additional POPF could identify patients who may benefit from additional surveillance, specific drains protocols, and preventive strategies.

To evaluate whether postoperative serum hyperamylasemia (POH), with drain fluid amylase (DFA) and C-reactive protein (CRP), improves the Fistula Risk Score (FRS) accuracy in assessing the risk of a postoperative pancreatic fistula (POPF).The FRS predicts POPF occurrence using intraoperative predictors with good accuracy but intrinsic limits.Outcomes of patients who underwent pancreaticoduodenectomies (PD) between 2016 and 2021 were evaluated across FRS risk zones and POH occurrence. POH consists of serum amylase activity greater than the upper limit of normal (52 U/l), persisting within the first 48 hours postoperatively (postoperative day -POD- 1 and 2).Out of 905 PDs, some FRS elements, namely soft pancreatic texture (OR 11.6), pancreatic duct diameter (OR 0.80), high-risk pathological diagnosis (OR 1.54), but not higher blood loss (OR 0.99), were associated with POH. POH was an independent predictor of POPF, which occurred in 46.8% of POH cases (P0.001). Once POH occurs, POPF incidence rises from 3.8% to 42.9%, 22.9% to 41.7%, and 48.9% to 59.2% in patients intraoperatively classified at low, moderate and high FRS risk, respectively. The predictive ability of multivariable models adding POD 1 drain fluid amylase, POD 1-2 POH and POD 3 C-reactive protein to the FRS showed progressively and significantly higher accuracy (AUC FRS=0.82, AUC FRS-DFA=0.85, AUC FRS-DFA-POH=0.87, AUC FRS-DFA-POH-CRP=0.90, DeLong always P0.05).POPF risk assessment should follow a dynamic process. The stepwise retrieval of early, postoperative biologic markers improves clinical risk stratification by increasing the granularity of POPF risk estimates and affords a possible therapeutic window before the actual morbidity of POPF occurs.

We consider the \begin{document}$ C^1 $\end{document}-Virtual Element Method (VEM) for the conforming numerical approximation of some variants of the Cahn-Hilliard equation on polygonal meshes. In particular, we focus on the discretization of the advective Cahn-Hilliard problem and the Cahn-Hilliard inpainting problem. We present the numerical approximation and several numerical results to assess the efficacy of the proposed methodology. Correction: Bari is added after the zip code 70125 in third author’s address. We apologize for any inconvenience this may cause.

In many applications the accurate representation of the computational domain is a key factor to obtain reliable and effective numerical solutions. Curved interfaces, which might be internal, related to physical data, or portions of the physical boundary, are often met in real applications. However, they are often approximated leading to a geometrical error that might become dominant and deteriorate the quality of the results. Underground problems often involve the motion of fluids where the fundamental governing equation is the Darcy law. High quality velocity fields are of paramount importance for the successful subsequent coupling with other physical phenomena such as transport. The virtual element method, as solution scheme, is known to be applicable in problems whose discretizations requires cells of general shape, and the mixed formulation is here preferred to obtain accurate velocity fields. To overcome the issues associated to the complex geometries and, at the same time, retaining the quality of the solutions, we present here the virtual element method to solve the Darcy problem, in mixed form, in presence of curved interfaces in two and three dimensions. The numerical scheme is presented in detail explaining the discrete setting with a focus on the treatment of curved interfaces. Examples, inspired from industrial applications, are presented showing the validity of the proposed approach.

The Outreach Cosmic Ray Activities (OCRA) project offers a platform for all outreach activities focusing on cosmic rays within the Italian Istituto Nazionale di Fisica Nucleare (INFN). Created in 2018, OCRA now counts 21 of the institute’s divisions all over Italy as members. The project’s core activity is the participation of all its members in the International Cosmic Day, organized by DESY, and inviting high school students to carry out hands-on measurements of the cosmic ray flux and learn about the related physics background. Two students from each division are then selected to participate in the annual OCRA science camp, a three-day full immersion into the life of a physicist. The national activities are complemented by local initiatives of the OCRA member groups: workshops and tutorship programs, science competitions and the development of new detectors for outreach activities offer a multitude of possibilities for students to engage with our researchers and to explore the world of cosmic rays. Since spring of 2020 OCRA also offers a series of online laboratories on its website https://web.infn.it/OCRA/, designed not only to be used by students individually but also to be used in the classroom by teachers. Here we will give an overview on all activities offered by OCRA with a particular focus on the 2020 online event organized in occasion of the International Cosmic Day, that saw the participation of more than 3000 students.

To characterize early postoperative serum pancreatic amylase (spAMY) trends after pancreatic resections.A postoperative spAMY elevation is a common finding but uncertainties remain about its meaning and prognostic implications.Analysis of patients who consecutively underwent pancreatectomy from 2016 to 2019. spAMY activity was assessed from postoperative day (POD) 0 to 3. Different patterns of spAMY have been identified based on the spAMY standard range (10-52 U/l).Three patterns were identified: (#1) spAMY values alwaysthe lower limit of normal/within the reference range /a single increase in spAMYupper limit of normal at any POD; (#2) Sustained increase in spAMY activity on POD 0 + 1; (#3) Sustained increase in spAMY activity including POD 1 + 2. Shifting through spAMY patterns was associated with increase morbidity (21% in #1 to 68% in #3 at POD 7; log rank 0.001). Almost all severe complications (at least Clavien-Dindo ≥3) occurred in patients with pattern #3 (15% vs. 3% vs. 5% in #1 and #2 at POD 7, p = 0.006), without difference considering3-times orthe spAMY normal limit (p = 0.85). POPF (9% in #1 vs. 48% in #3, p 0.001) progressively increased across patterns. Pre-operative diabetes (OR 0.19), neoadjuvant therapy (OR 0.22), pancreatic texture (OR 8.8), duct size (OR 0.78), and final histology (OR 2.2) were independent predictors of pattern #3.A sustained increase in spAMY activity including POD 1 + 2 (#3) represents an early postoperative predictor of overall and severe early morbidity. An early and dynamic evaluation of spAMY could crucially impact the subsequent clinical course with relevant prognostic implications.