Phenolic and Volatile Composition and Antioxidant Properties of the Leaf Extract of Brassica fruticulosa subsp. fruticulosa (Brassicaceae) Growing Wild in Sicily (Italy)

In continuation of research conducted on species of the spontaneous flora of Sicily (Italy) belonging to the Brassicaceae family, Brassica fruticulosa subsp. fruticulosa was selected. It is an edible species utilized in Sicilian traditional medicine. In this study, for the first time, the phenolic and the volatile compounds and the antioxidant properties of the hydroalcoholic extract obtained from the leaves of B. fruticulosa subsp. fruticulosa were characterized. Through HPLC-PDA/ESI-MS analysis, a total of 22 polyphenolic compounds (20 flavonoids and 2 phenolic acids) were identified, with 3-hydroxiferuloylsophoroside-7-O-glucoside (1.30 mg/g ± 0.01) and kaempferol-3-O-feruloylsophoroside-7-O-glucoside (1.28 mg/g ± 0.01) as the most abundant compounds. Through SPME-GC/MS several volatiles belonging to different chemical classes were characterized, with nitriles and aldehydes accounting for more than 54% of the whole volatile fraction. The extract of B. fruticulosa subsp. fruticulosa showed moderate activity in the DPPH assay (IC₅₀ = 1.65 ± 0.08 mg/mL), weak reducing power (17.47 ± 0.65 ASE/mL), and good chelating properties (IC₅₀ = 0.38 ± 0.02 mg/mL), reaching approximately 90% activity at the highest tested concentration. Lastly, the extract was non-toxic against Artemia salina, indicating its potential safety. According to the findings, it can be stated that B. fruticulosa subsp. fruticulosa represents a new valuable source of bioactive compounds.     

Charge-solvated versus protonated salt forms of cyclodepsipeptide toxins in electrospray: Dissociation of alkali-cationized forms enables straightforward sequencing of cereulide

Bacillus cereus is responsible for foodborne outbreaks worldwide. Among the produced toxins, cereulide induces nausea and vomiting after 30 min to 6 h following the consumption of contaminated foods. Cereulide, a cyclodepsipeptide, is an ionophore selective to K⁺ in solution. In electrospray, the selectivity is reduced as [M + Li]⁺; [M + Na]⁺ and [M + NH₄]⁺ can also be detected without adding corresponding salts. Two forms are possible for alkali-cationized ions: charge-solvated (CS) that exclusively dissociates by releasing a bare alkali ion and protonated salt (PS), yielding alkali product ions by covalent bond cleavages (CBC) promoted by mobile proton. Based on a modified peptide cleavage nomenclature, the PS product ion series ( b , a , [ b + H₂O] and [ b + C_nH_2nO] [n = 4, 5]) are produced by Na⁺/Li⁺/K⁺-cationized cereulide species that specifically open at ester linkages followed by proton mobilization promoting competitive ester CBC as evidenced under resonant collision activation. What is more, unlike the sodiated or lithiated cereulide, which regenerates little or no alkali cation, the potassiated forms lead to an abundant K⁺ regeneration. This occurs by splitting of (i) the potassiated CS forms with an appearance threshold close to that of the PS first fragment ion generation and (ii) eight to four potassiated residue product ions from the PS forms. Since from Na⁺/Li⁺-cationized cereulide, (i) the negligible Na⁺/Li⁺ regeneration results in a higher sensibility than that of potassiated forms that abundantly releasing K⁺, and (ii) a better sequence recovering, the use of Na⁺ (or Li⁺) should be more pertinent to sequence isocereulides and other cyclodepsipeptides.     

Analgesic and Anticancer Activity of Benzoxazole Clubbed 2-Pyrrolidinones as Novel Inhibitors of Monoacylglycerol Lipase

Ten benzoxazole clubbed 2-pyrrolidinones (11–20) as human monoacylglycerol lipase inhibitors were designed on the criteria fulfilling the structural requirements and on the basis of previously reported inhibitors. The designed, synthesized, and characterized compounds (11–20) were screened against monoacylglycerol lipase (MAGL) in order to find potential inhibitors. Compounds 19 (4-NO₂ derivative) and 20 (4-SO₂NH₂ derivative), with an IC₅₀ value of 8.4 and 7.6 nM, were found most active, respectively. Both of them showed micromolar potency (IC₅₀ value above 50 µM) against a close analogue, fatty acid amide hydrolase (FAAH), therefore considered as selective inhibitors of MAGL. Molecular docking studies of compounds 19 and 20 revealed that carbonyl of 2-pyrrolidinone moiety sited at the oxyanion hole of catalytic site of the enzyme stabilized with three hydrogen bonds (~2 Å) with Ala51, Met123, and Ser122, the amino acid residues responsible for the catalytic function of the enzyme. Remarkably, the physiochemical and pharmacokinetic properties of compounds 19 and 20, computed by QikProp, were found to be in the qualifying range as per the proposed guideline for good orally bioactive CNS drugs. In formalin-induced nociception test, compound 20 reduced the pain response in acute and late stages in a dose-dependent manner. They significantly demonstrated the reduction in pain response, having better potency than the positive control gabapentin (GBP), at 30 mg/kg dose. Compounds 19 and 20 were submitted to NCI, USA, for anticancer activity screening. Compounds 19 (NSC: 778839) and 20 (NSC: 778842) were found to have good anticancer activity on SNB-75 cell line of CNS cancer, exhibiting 35.49 and 31.88% growth inhibition (% GI), respectively.     

H2S Sensors: Fumarate‐Based fcu‐MOF Thin Film Grown on a Capacitive Interdigitated Electrode

Herein we report the fabrication of an advanced sensor for the detection of hydrogen sulfide (H₂S) at room temperature, using thin films of rare‐earth metal (RE)‐based metal–organic framework (MOF) with underlying fcu topology. This unique MOF‐based sensor is made via the in situ growth of fumarate‐based fcu ‐MOF (fum‐ fcu ‐MOF) thin film on a capacitive interdigitated electrode. The sensor showed a remarkable detection sensitivity for H₂S at concentrations down to 100 ppb, with the lower detection limit around 5 ppb. The fum‐ fcu ‐MOF sensor exhibits a highly desirable detection selectivity towards H₂S vs. CH₄, NO₂, H₂, and C₇H₈ as well as an outstanding H₂S sensing stability as compared to other reported MOFs.     

A new strategy for the numerical modeling of a weld pool

Welding processes involve high temperatures and metallurgical and mechanical consequences that must be controlled. For this purpose, numerical simulations have been developed to study the effects of the process on the final structure. During the welding process, the material undergoes thermal cycles that can generate different physical phenomena, like phase changes, microstructure changes and residual stresses and distortions. But the accurate simulation of transient temperature distributions in the part needs to carefully take account of the fluid flow in the weld pool. The aim of this paper is thus to propose a new approach for such a simulation taking account of surface tension effects (including both the “curvature effect” and the “Marangoni effect”), buoyancy forces and free surface motion.The proposed approach is validated by two numerical tests from the literature: a sloshing test and a plate subjected to a static heat source. Then, the effects of the fluid flow on temperature distributions are discussed in a hybrid laser/arc welding example.     

Chemical Composition,Antifungal and Anti-Biofilm Activities of Volatile Fractions of Convolvulus althaeoides L. Roots from Tunisia

The antifungal drugs currently available and mostly used for the treatment of candidiasis exhibit the phenomena of toxicity and increasing resistance. In this context, plant materials might represent promising sources of antifungal agents. The aim of this study is to evaluate for the first time the chemical content of the volatile fractions (VFs) along with the antifungal and anti-biofilm of Convolvulus althaeoides L. roots. The chemical composition was determined by gas chromatography coupled to a flame ionization detector and mass spectrometry. In total, 73 and 86 chemical compounds were detected in the n-hexane (VF1) and chloroform (VF2) fractions, respectively. Analysis revealed the presence of four main compounds: n-hexadecenoic acid (29.77%), 4-vinyl guaiacol (12.2%), bis(2-ethylhexyl)-adipate (9.69%) and eicosane (3.98%) in the VF extracted by hexane (VF1). n-hexadecenoic acid (34.04%), benzyl alcohol (7.86%) and linoleic acid (7.30%) were the main compounds found in the VF extracted with chloroform (VF2). The antifungal minimum inhibitory concentrations (MICs) of the obtained fractions against Candida albicans, Candida glabrata and Candida tropicalis were determined by the micro-dilution technique and values against Candida spp. ranged from 0.87 to 3.5 mg/mL. The biofilm inhibitory concentrations (IBF) and sustained inhibition (BSI) assays on C. albicans, C. glabrata and C. tropicalis were also investigated. The VFs inhibited biofilm formation up to 0.87 mg/mL for C. albicans, up to 1.75 mg/mL against C. glabrata and up to 0.87 mg/mL against C. tropicalis. The obtained results highlighted the synergistic mechanism of the detected molecules in the prevention of candidosic biofilm formation.     

Physical properties of NxTiO2 prepared by sol–gel route

The compounds N_xTiO₂(x=0, 0.05, 0.1, 0.2) with the anatase structure have been synthesized by Sol–Gel method using Tri-ethyl Amine as nitrogen source and their optical, electrical and electrochemical properties are investigated. The electrical conductivity and thermoelectric power are measured in the temperature rang 300–600 K. The samples exhibit p-type behavior in contrast to TiO₂. The doped-samples exhibit two optical transitions (2.35≤E_h−Vis(eV)≤2.55; 1.97≤E_l−Vis (eV)≤2.06) directly allowed in the visible region, while only one transition is observed in UV region (E_UV∼3.00 eV). Pure TiO₂ shows direct band gap transition of 3.17 eV. The results confirm experimentally the calculations of Di. Valentin et al. [42]. The transitions E_h−Vis and E_l−Vis are attributed respectively to the promotion of electrons from the localized N 2p and π^? N–O bond to the conduction band. In all cases, E_UV is associated to the forbidden band energy. Though that the conductivity is generally improved by doping process, only N_0.05TiO₂ and N_0.1TiO₂ shows an enhanced mobility. The mechanism of conduction takes place by small polaron hopping. The band edge positions of N_xTiO₂ (x=0, 0.05, 0.1, 0.2) at room temperature is predicted from the obtained physical properties. This study proves experimentally the principal role of nitrogen in doping process and permits the electronic states localization associated with N-impurities in TiO₂ anatase.     

Solution of the Spinless Salpeter Equation with a Time-Dependent Linear Potential

We derive the general solution of the semi-relativistic spinless Salpeter equation in the presence of a time-dependent linear potential via the Lewis–Riesenfeld framework and using two forms of the invariant. For comparison, we reobtain the solution in the momentum-space directly by applying a time-momentum transformation to the involved partial differential equation. We also investigate the classical-quantum correspondence for the model in the case of time-periodic force using a momentum-space Gaussian wave-packet.     

Managing the exchange of information in product development

In the present paper, we develop a dynamic programming (DP) model of the product development (PD) process. We conceptualize product development as a sequence of decisions: whether to incorporate a piece of information that just arrived (i.e. became available) or wait longer. We utilize this formulation to analyze different situations that depend on the type, and nature of information that is exchanged: stationary versus dynamic information. We derive optimal decision rules to determine whether (and when) to incorporate for each case. An analysis of the model results in several important findings. First, we must not necessarily incorporate all available information that is related to the design activity. Specifically, once the information collection exceeds certain value, the design team should stop collecting further information. Second, only when past design work accumulates to a certain threshold value should the team include the latest information and perform rework. Large uncertainty of the information and large sensitivity of the design activity makes the incorporation of new information less likely. Finally, managerial implications are discussed with several numerical examples.