A Stochastic Petri Net-Based Model of the Involvement of Interleukin 18 in Atherosclerosis

Interleukin 18 (IL-18) is a proinflammatory and proatherogenic cytokine with pleiotropic properties, which is involved in T and NK cell maturation and the synthesis of other inflammatory cytokines and cell adhesion molecules. It plays a significant role in orchestrating the cytokine cascade, accelerates atherosclerosis and influences plaque vulnerability. To investigate the influence of IL-18 cytokine on atherosclerosis development, a stochastic Petri net model was built and then analyzed. First, MCT-sets and t-clusters were generated, then knockout and simulation-based analysis was conducted. The application of systems approach that was used in this research enabled an in-depth analysis of the studied phenomenon. Our results gave us better insight into the studied phenomenon and allow revealing that activation of macrophages by the classical pathway and IL-18-MyD88 signaling axis is crucial for the modeled process.     

Influence of roasting pretreatment on high‐oleic rapeseed oil quality evaluated by analytical and sensory approaches

Qualitative and quantitative effects on the contents of minor components of cold‐pressed high‐oleic rapeseed oil (HORO) were evaluated in a function of different roasting temperatures (80, 100, 120 and 140 °C). Along with roasting temperature elevation, a significant increase in the content of total tocopherols up to 32% (mainly γ‐T homologue) and a slight increase of total sterols concentration (up to 5%) were observed, whereas no significant changes in the fatty acid composition occurred during seeds thermal pretreatment. Additionally, an increased degree of hydrolysis and lipid oxidation was reported; however, obtained results were within codex limits. The peroxide value of the oil ranged from 1.30 to 2.34 mEq O₂ kg^?1, while the acid value did not exceed 0.46 mg/KOH g. Principal component analysis was capable of differentiating between rapeseed oils acquired from seeds pretreated with different roasting temperatures.     

Application of lyophilization to prepare the nitrifying bacterial biofilm for imaging with scanning electron microscopy

Structure of bacterial biofilms may be investigated using several variants of scanning electron microscopy (SEM). We apply lyophilization to prepare nitrifying bacterial biofilm for conventional SEM imaging in high-vacuum mode (CSEM). We therefore replace standard biofilm fixation in glutaraldehyde cross-linking, ethanol dehydration, and critical-point drying (CPD) with less-invasive low-temperature drying by sublimation in vacuum. We compare this approach with: (1) standard preparation with glutaraldehyde fixation, ethanol dehydration, and CPD before CSEM, (2) cryo-sputter preparation of rapidly frozen biofilm in hydrated state (cryo-SEM), and (3) in situ observation without any sample pretreatment in environmental SEM. Combined imaging with these modalities revealed two distinct immobilization patterns on the polyurethane foam: (1) large irregular aggregates (flocs) of bacterial biofilm that exist as irregular biofilm fragments, rope-like structures, or biofilm layers on the foam surface; (2) biofilm threads adherent to the surface of polyurethane foam. Our results indicate that lyophilization was suitable for preservation of bacterial cells and many forms of structure of extracellular matrix. The lyophilized material could be imaged with high resolution (using CSEM) to generate structural information complementary to that obtained with other SEM techniques.     

Reliability and maintenance strategy for systems with aging‐dependent components

An innovative approach is presented for the reliability analysis of aging multistate systems that considers the subsystems and their components' dependency. A reliability function is determined for an aging series system with the component dependency following the local load‐sharing rule, and a reliability function is determined for an aging “m out of n” system with the component dependency following the equal load‐sharing rule. Linking the results of those load‐sharing models, a mixed‐dependency model for multistate “m out of l”‐series systems is constructed by assuming the dependence between subsystems connected in series under the local load‐sharing rule and the dependence between their components under the equal load‐sharing rule. As a special case, the reliability of this system, modeled using piecewise exponential reliability functions, is considered, and the results are applied to characterize shipyard rope elevator reliability. Finally, the maintenance of this elevator as a repairable multistate system is analyzed with the time of renovation ignored.     

Oxidative and microbial stability of poultry meatballs added with coriander extracts and packed in cold modified atmosphere

The aim of the study was to determine the effects of adding of coriander extracts to turkey meatballs. Meat samples were stored in modified atmosphere at 4°C ± 1°C for 9 days. The addition of coriander extract at 500 ppm level delayed the process of lipid oxidation for the period of 6 days of storage and growth inhibition of aerobic microorganisms for the period of 9 days of storage. The usage of a dose of 500 ppm as well as a dose of 200 ppm had no significant effect on the sensory features, but had an impact on colour parameters of the meatballs. In the groups with coriander extract, volatile terpenes were identified.     

The application of organophosphorus flame‐retardants in epoxy resin

The influence of two novel aryl phosphate mixtures on fire retardancy and the thermal stability of epoxy resin were studied. Combustion behavior, decomposition pathway, and thermal and thermo‐oxidative degradation of the epoxy resin were examined by using the limiting oxygen index, vertical burning test (UL‐94), cone calorimeter test, thermogravimetric analysis, and thermogravimetry coupled with Fourier‐transform infrared spectroscopy. The morphology of the residues from the degradation of flame‐retarded epoxy resins was investigated by using scanning electron microscopy. Data from the cone calorimeter test demonstrated that the total heat evolved, heat release rate, and peak heat release rate decreased significantly when the epoxy resin contained these retardants. Moreover, a 20 wt% of both phosphate mixtures in the epoxy resin allowed for a satisfactory oxygen index (30–33%) and for UL‐94 V2 to be achieved. The condensed‐phase and gas‐phase actions of these aryl phosphate flame‐retardants are proposed as the mode of flame‐retardancy in epoxy resins. J. VINYL ADDIT. TECHNOL., 23:142–151, 2017. © 2015 Society of Plastics Engineers     

Induction of Oxidative Stress by Sunflower Phytotoxins in Germinating Mustard Seeds

The aim of this study was to investigate the phytotoxic effect of sunflower on physiological and biochemical processes during germination of mustard seeds (Sinapis alba L. cv. Nakielska). To exclude the involvement of osmotic stress in seed reaction to phytotoxic compounds, we compared the effect of 10% (w/v) water extract from sunflower (Helianthus annuus L. cv. Ogrodowy) leaves and 28.4% (w/v) polyethylene glycol (PEG) 8000 solution characterized by an equal Ψ = −1 MPa. We evaluated (1) the amount of hydrogen peroxide (H₂O₂); (2) activities of antioxidant enzymes: superoxide dismutase, catalase, and glutathione reductase; (3) membrane permeability; and (4) level of malondialdehyde (MDA). Both, sunflower compounds and PEG solutions inhibited mustard seed germination, but only phytotoxins caused an increase in the cell membrane permeability, MDA level, H₂O₂ concentration, and alterations in activities of antioxidant enzymes. Our results demonstrate that despite the activation of the antioxidant system by sunflower phytotoxins, reactive oxygen species accumulation caused cellular damage, which resulted in the decrease of germinability and gradual loss of seed vigor. It seems that the negative effect of sunflower on germination of mustard seeds is mostly because of its toxicity and not to its contribution to osmotic potential.