A constraint-based variability modeling framework

Constraint-based variability modeling is a flexible, declarative approach to managing solution-space variability. Product variants are defined in a top-down manner by successively restricting the admissible combinations of product artifacts until a specific product variant is determined. In this paper, we illustrate the range of constraint-based variability modeling by discussing two of its extreme flavors: constraint-guarded variability modeling and constraint-driven variability modeling. The former applies model checking to establish the global consistency of product variants which are built by manual specification of variations points, whereas the latter uses synthesis technology to fully automatically generate product variants that satisfy all given constraints. Each flavor is illustrated by means of a concrete case study.     

Application of nine air-dried Capsicum annum cultivars as food preservative: Micronutrient content,antioxidant activity,and foodborne pathogens inhibitory effects

Capsicum annum cultivars Yellow cayenne, Portafortuna, Idealino, Sole, Duemila, Pellegrino, Fantasia, Loco, and Effix were investigated for their antioxidant properties and foodborne pathogens inhibitory activity. The total phenols, flavonoids, anthocyanins, capsaicinoids, carotenoids, ascorbic acid, and vitamin E content were also determined. Duemila and Portafortuna cultivars showed the highest total phenol content with values of 924.3 and 935.0 mg of chlorogenic acid equivalents/100 g dried weight, respectively. Idealino pepper presented the highest capsaicin content (2932.1 μg/g dried weight). The antioxidant capacity was evaluated by using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid test, 2,2-diphenyl-1-picrylhydrazyl test, and ferric reducing ability power assay. Both Pellegrino and Idealino samples exhibited a promising radical scavenging ability against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radical with IC₅₀ values of 45.2 and 45.7 μg/mL, respectively. All the extracts were able to inhibit the growth of Staphylococcus aureus and Listeria monocytogenes investigated strains. The most active are Effix and Fantasia peppers with minimal inhibitory concentration between 12.5 and 25.0 mg/mL, respectively. Overall, these results support the use of these pepper species as dried extract in food preservation.     

Nondegradative additive manufacturing of medical grade copolyesters of high molecular weight and with varied elastic response

Although additive manufacturing through melt extrusion has become increasingly popular as a route to design scaffolds with complex geometries the technique if often limited by the reduction in molecular weight and the viscoelastic response when degradable aliphatic polyesters of high molecular weight are used. Here we use a melt extruder and fused filament fabrication printer to produce a reliable nondegradative route for scaffold fabrication of medical grade copolymers of L-lactide, poly(ε-caprolactone-co-L-lactide), and poly(L-lactide-co-trimethylene carbonate). We show that degradation is avoided using filament extrusion and fused filament fabrication if the process parameters are deliberately chosen based upon the rheological behavior, mechanical properties, and polymer composition. Structural, mechanical, and thermal properties were assessed throughout the process to obtain comprehension of the relationship between the rheological properties and the behavior of the medical grade copolymers in the extruder and printer. Scaffolds with a controlled architecture were achieved using high-molecular-weight polyesters exhibiting a large range in the elastic response causing negligible degradation of the polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48550.     

Inactivation of Staphylococcus aureus by the synergistic action of charged and reactive plasma particles

In this paper, a low-pressure capacitively coupled plasma discharge sustained in an argonoxygen mixture was studied in order to evaluate its properties in terms of inactivation of Staphylococcus aureus. The plasma parameters as electron temperature and plasma density were measured by the Langmuir probe (N_e ≈ 10¹⁵ m⁻³, T_e ≈ 1.5 eV), while the neutral atom density was in the range of 10²¹ m⁻³. In the plasma phase, oxygen radicals were taken as reference of the reactive species with antimicrobial activity, and oxygen spectral lines, over a range of plasma process parameters, were investigated by the optical emission spectroscopy. Optimal plasma conditions were found, and a count reduction of 4 log in a few minutes of the bacterium proves the potentiality of an industrial grade plasma reactor as a sterilization agent.     

Immunotherapy for Biliary Tract Cancer in the Era of Precision Medicine: Current Knowledge and Future Perspectives

Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40–50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.     

Characterization of Gram‐Negative Psychrotrophic Bacteria isolated from Italian Bulk Tank Milk

Eighty psychrotrophic bacterial strains, isolated from different northwest Italian bulk tank milks destined for Grana Padano cheese production, were identified by 16S rRNA gene amplification and partial sequence analysis of the rpoB gene. Pseudomonas spp. were the most commonly occurring contaminants, P. fluorescens being the predominant isolated species, along with Enterobacteriaceae, primarily Serratia marcescens. RAPD‐PCR was used to study genetic variability and distinguish closely related strains; a high degree of genetic heterogeneity among the strains was highlighted. All the strains were characterized for their ability to produce proteases, lipases and lecithinases at different temperatures (7, 22, and 30 °C). Forty‐one of the psychrotrophic strains were positive for all the enzymatic activities. The highest number of positive strains for all the incubation temperatures was found for lipolytic activity (59), followed by proteolytic (31) and lecithinase (28) activities, and the enzymatic traits varied among the Pseudomonas and Enterobacteriaceae strains. The proteolytic psychrotrophic strains were screened for the presence of the aprX gene, coding for a heat‐resistant metalloprotease in Pseudomonas spp. The aprX gene was detected in 19 of 63 Pseudomonas strains, and was widespread in the P. fluorescens strains (14/19).     

Fining white wine with plant proteins: effects of fining on proanthocyanidins and aroma components

Plant-derived insoluble proteins (wheat gluten, and isolates from pea, lentil, and soybean) were used as fining agents in model white wine (made from Catalanesca grapes) after cold stabilization. Plant proteins were effective in giving a fast and remarkable decrease in turbidity. GC/MS and HPLC/MS approaches indicated that individual proteins had a different impact on the levels of compounds relevant to wine stability. Protein stability of wine was not affected by fining with plant proteins. Lentil proteins and gluten gave the best removal of monomeric and dimeric flavonol. Both caused a decrease in the total content of fermentative aroma compounds, such as ethyl esters, acetate esters, and alcohols. Lentil proteins had the highest impact on the aroma components, giving a marked decrease in aroma components. Gluten may thus be regarded as giving the best balance between fining efficacy and retention of aroma compounds. Also, gluten in the treated wines remained well below the suggested threshold for gluten-free foods. This study provides a methodological frame for thorough characterization of the impact of specific interventions on key wine components.     

Pathogenetic Mechanisms of Hypertension–Brain-Induced Complications: Focus on Molecular Mediators

There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies.     

Dietary krill oil increases docosahexaenoic acid and reduces 2-arachidonoylglycerol but not N-acylethanolamine levels in the brain of obese Zucker rats

Evidence suggests that dietary long chain polyunsaturated fatty acids (LCPUFAs), and particularly those belonging to the n-3 family, may influence the brain fatty acid profile and, thereby, the biosynthesis of endocannabinoids in rodents. However, the doses used are usually quite high and not comparable with human intake. Recently, we have shown that relatively low doses of dietary n-3 LCPUFAs (4 weeks), in the form of either fish or krill oil, balanced for EPA and DHA content, and against a control diet with no EPA and DHA and similar contents of oleic, linoleic and α-linolenic acids, lower the concentrations of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in the visceral adipose tissue, and of AEA in the liver and heart, of obese Zucker rats. This, in turn, is associated with lower levels of arachidonic acid in membrane phospholipids and with amelioration of some metabolic syndrome parameters. We investigated here whether in Zucker rats, under the same conditions, fish and krill oil are also able to influence LCPUFA and endocannabinoid profiles in brain. Only krill oil was able to increase significantly DHA levels in brain phospholipids, with no changes in arachidonic acid. DHA increase was associated with lower levels of 2-AG in the brain, whereas AEA and its congeners, N-palmitoylethanolamine and N-oleoylethanolamine, were unchanged. We conclude that, despite the strong impact of dietary n-3 fatty acid on endocannabinoid levels previously observed in peripheral tissues, in the brain only 2-AG is affected by dietary krill oil, suggesting that the beneficial effect of the latter on the metabolic syndrome is mostly exerted by modifying peripheral endocannabinoids. Nevertheless, possible effects of dietary krill oil in the brain through modification of 2-AG levels deserve further investigation.     

Poly(DL-lactide-co-ε-caprolactone) and poly(DL-lactide-co-glycolide) blends for biomedical application: Physical properties,cell compatibility,and in vitro degradation behavior

Poly(DL-lactide-co-ε-caprolactone) (PLCL) and poly(DL-lactide-co-glycolide) (PLGA) blends of various compositions were prepared. Fractured sections of PLCL/PLGA blends did not evidence phase separation and blend glass transition temperatures suggested some degree of blend compatibility. The elastic modulus showed a negative deviation from the additive law of mixture. Superior biocompatibility in terms of fibroblast NIH 3T3 cell adhesion and proliferation, better mechanical properties, and a more homogeneous phase were obtained with PLCL/PLGA 25/75 blend. Rapid degradation of PLCL phase (4–8 weeks) in PLCL/PLGA 25/75 blend led to a porous structure, which makes it a potential candidate for drug delivery systems.