A self-parametrization framework for meta-heuristics

Even while the scientific community has shown great interest in the analysis of meta-heuristics, the analysis of their parameterization has received little attention. It is the parameterization that will adapt a meta-heuristic to a problem, but it is still performed, mostly, empirically. There are multiple parameterization techniques; however, they are time-consuming, requiring considerable computational effort and they do not take advantage of the meta-heuristics that they parameterize. In order to approach the parameterization of meta-heuristics, in this paper, a self-parameterization framework is proposed. It will automatize the parameterization as an optimization problem, precluding the user from spending too much time on parameterization. The model will automate the parameterization through two meta-heuristics: A meta-heuristic of the solution space and one of the parameter space. To analyze the performance of the framework, a self-parameterization prototype was implemented. The prototype was compared and analyzed in a SP (scheduling problem) and in the TSP (traveling salesman problem). In the SP, the prototype found better solutions than those of the manually parameterized meta-heuristics, although the differences were not statistically significant. In the TSP, the self-parameterization prototype was more effective than the manually parameterized meta-heuristics, this time with statistically significant differences.This work was supported by national funds through the FCT - Fundação para a Ciência e Tecnologia through the R&D Units Project Scopes: UIDB/00319/2020, and EXPL/EME-SIS/1224/2021

In vitro assessment of the synergism between extracts of Zanthoxylum zanthoxyloides and Zanthoxylum leprieurii and some standard antibiotics

Research ArticlePurpose: To survive in harsh environments, plants developed functional and metabolic adaptive mechanisms. One of the most relevant defense strategies is the biosynthesis of secondary metabolites, including terpenoids, alkaloids, flavonoids, and phenolics that are accumulated in cellular organelles or secretory structures. Hence, plants are recognized as a valuable source of natural products and for thousands of years very diverse herbal formulations were created to treat several diseases. Zanthoxylum zanthoxyloides and Zanthoxylum leprieurii, two Rutaceae species native to Guinea-Bissau, are well known for their ethnopharmacological relevance. Methods: In the present study, the in vitro antimicrobial activity of these plants against human pathogens was assessed and the phytochemical profile was screened. The extracts of roots and young leaves were obtained by sequential extraction of increasing polarity (n-hexane, CH2Cl2, EtOAc, MeOH and H2O) and tested against Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined, as well as the evaluation of the synergic potential of the extracts. Results: Z. leprieurii leaves extracts, the most apolar ones, had the highest antimicrobial activity, being able to inhibit the growth of Enterococcus hirae and all the Staphylococcus strains assayed, including the resistant ones. A synergic effect between the Zanthoxylum species extracts and standard antibiotics was found, reverting the activity of resistant strains. The phytochemical screening revealed the presence of terpenes, flavonoids, and phenolic compounds, known to have antibacterial properties. Conclusions: The obtained results point to the validation of their use in tradition medicine and emphasize the worthwhile of additional studies of these species to better understand the compounds and mechanisms that may be valuable to restore antibacterial activityinfo:eu-repo/semantics/publishedVersio

Evaluation of the Simulated Annealing and the Discrete Artificial Bee Colony in the Weight Tardiness Problem with Taguchi Experiments Parameterization

Meta-Heuristics (MH) are the most used optimization techniques to approach Complex Combinatorial Problems (COPs). Their ability to move beyond the local optimums make them an especially attractive choice to solve complex computational problems, such as most scheduling problems. However, the knowledge of what Meta-Heuristics perform better in certain problems is based on experiments. Classic MH, as the Simulated Annealing (SA) has been deeply studied, but newer MH, as the Discrete Artificial Bee Colony (DABC) still need to be examined in more detail. In this paper DABC has been compared with SA in 30 academic benchmark instances of the weighted tardiness problem (1 parallel to Sigma w(j)T(j)). Both MH parameters were fine-tuned with Taguchi Experiments. In the computational study DABC performed better and the subsequent statistical study demonstrated that DABC is more prone to find near-optimum solutions. On the other hand SA appeared to be more efficient.This work is supported by FEDER Funds through the "Programa Operacional Factores de Competitividade - COMPETE" program and by National Funds through FCT "Fundacao para a Ciencia e a Tecnologia" under the project: PEst-OE/EEI/UI0760/2014, and PEst2015-2020.info:eu-repo/semantics/publishedVersio

Edible films as oral delivery systems for xanthines extracted from medicinal plants: an experimental design approach

Two formulations of edible films intended for oral delivery of therapeutic xanthines were developed, following an experimental design approach. Gelatin type A and sodium carboxymethylcellulose were used as polymeric matrices with different physico-chemical nature. Caffeine, a well-known methylxhanthine, was used as model bioactive molecule, representing overall xanthines (e.g. caffeine, theophylline, theobromine) extracted from medicinal plants. Fourier-transform infrared spectroscopy (FTIR) analysis was performed to outwit the formation of covalent bonds between caffeine and the matrix of edible films. Scanning electron microscopy (SEM) was performed to assess if caffeine was homogeneously dispersed on the matrix of edible films. Simulation of gastrointestinal tract and ex vivo permeability studies across intestinal mucosa were performed to predict the delivery profile of caffeine from developed formulations of edible films. Gelatin type A-based edible films offered a slow release of caffeine whereas sodium carboxymethylcellulose-based edible films promote an immediate release of caffeine.info:eu-repo/semantics/publishedVersio

Bovine whey proteins - overview on their main biological properties

Whey, a liquid by-product, is widely accepted to contain many valuable constituents. These include especially proteins that posses important nutritional and biological properties – particularly with regard to promotion of health, as well as prevention of diseases and health conditions. Antimicrobial and antiviral actions, immune system stimulation, anticarcinogenic activity and other metabolic features have indeed been associated with such whey proteins, as a-lactalbumin, b-lactoglobulin, lactoferrin, lactoperoxidase, and bovine serum albumin. The most important advances reported to date pertaining to biological properties of whey proteins are reviewed in this communication

Sweet whey cheese matrices inoculated with the probiotic strain Lactobacillus paracasei LAFTI® L26

Consumption of dairy products containing viable probiotic strains has increased dramatically in recent years, owing to general health claims associated therewith. This trend has boosted diversification of the portfolio of said products, including whey cheese matrices. However, taking into account the relatively poor organoleptic and textural features of these matrices, improvement is in order via incorporation of selected additives, provided that viability of the strains is duly assayed. Lactobacillus paracasei LAFTI® L26 was accordingly incorporated into whey protein solid matrices, in the presence of several additives aimed at enhancing their organoleptic appeal and textural performance. These matrices were produced from a combination of either ovine or bovine whey (or a mixture thereof) with ovine milk, and were inoculated at 10% (v/v) with the probiotic strain. Sugar, sugar and aloe vera, sugar and chocolate, and sugar and jam were further added, and the resulting products were then stored at 7 ◦C for 21 d. In general, viable cell numbers remained high in all experimental matrices throughout storage. Despite the observed low extents of breakdown, proteolytic activities by the end of storage were higher in matrices containing jam. Furthermore, L. paracasei partially converted lactose into lactic acid in these matrices. Additives enhanced the organoleptic features of whey cheeses, and produced different textural patterns. The higher sensory scores were attained by matrices containing sugar: sugar and aloe vera received the best scores by 3 d of storage, but these scores decreased as storage time elapsed

Incorporation of PLGA nanoparticles into guar-gum films as a new buccal delivery

info:eu-repo/semantics/publishedVersio