Multi-asset minority games

We study analytically and numerically Minority Games in which agents may invest in different assets (or markets), considering both the canonical and the grand-canonical versions. We find that the likelihood of agents trading in a given asset depends on the relative amount of information available in that market. More specifically, in the canonical game players play preferentially in the stock with less information. The same holds in the grand canonical game when agents have positive incentives to trade, whereas when agents payoff are solely related to their speculative ability they display a larger propensity to invest in the information-rich asset. Furthermore, in this model one finds a globally predictable phase with broken ergodicity

Multi-asset minority games

We study analytically and numerically Minority Games in which agents may invest in different assets (or markets), considering both the canonical and the grand-canonical versions. We find that the likelihood of agents trading in a given asset depends on the relative amount of information available in that market. More specifically, in the canonical game players play preferentially in the stock with less information. The same holds in the grand canonical game when agents have positive incentives to trade, whereas when agents payoff are solely related to their speculative ability they display a larger propensity to invest in the information-rich asset. Furthermore, in this model one finds a globally predictable phase with broken ergodicity

Bio-synthesised fibrous-based meshes for abdominal hernia with enhanced mechanical and antimicrobial properties

Abdominal hernia (AH) encompasses the most prevalent types of hernia: inguinal, umbilical and incisional. Notwithstanding current hernia complications represent a low death toll (nearly 0.001 % in developed countries), non-reducible hernias are the most severe cases, which require urgent surgical intervention due to their life-threatening nature. In a single year, at the United States of America, more than 800 thousand surgeries are performed to repair inguinal hernias. Abdominal hernia ubiquitous symptoms include pain, which may represent a mild discomfort or even an impairing morbidity. Nevertheless, some patients suffer from morbidity in the post-operative period. Recurrence was reduced when the application of a propylene mesh replaced primary suture repair more than 60 years ago. Surprisingly, currently the most prevalent hernia mesh materials are based on petrochemical plastics such as polypropylene, polyester, polystyrene and expanded polytetrafluoroethylene. Unfortunately, despite the plethora of commercial hernia meshes, an improvement of the hernia meshes is still warranted, since petrochemical materials exhibit a deterioration over time which generate complications and recurrence. This project envisages the complete replacement of the conventional plastic-based material of hernia meshes by a fully bio- based material with superior mechanical properties: bacterial nanocellulose (BNC). BNC is synthesized by bacteria and is composed of a 3D matrix of 100 % nanofibrils of cellulose, each with a diameter ranging between 20 to 100 nm. When BNC producing bacterium are cultured in static culture, the BNC is formed as membrane (nanoporous mesh comprising pores of 100 to 300 nm in diameter) at the surface of the culture medium and adopts the shape of the available surface. Therefore, it is easy to control the membrane surface shape, as well as its thickness, which can be controlled by the incubation time (longer incubation time will result in a larger thickness). The selection of the most adequate bacterium for the production of the hernia mesh will be performed Nevertheless, for a hernia mesh to be viable it requires pores with a specific diameter to allow the permeability of leukocytes, fibroblasts, and permit the arrangement of collagen and blood vessels. Per se, the BNC mesh does not possess such large specific pores with the required diameter (> 75 μm), thus it is proposed the design and development of a template to achieve a AH mesh that meets the necessary requirements. Furthermore, due to the high complexity of hernia mesh infection, which is extremely difficult to adequately treat without removing the mesh, this project envisages the functionalization of BNC AH mesh with antimicrobial properties. Two approaches will be considered for the BNC AH mesh functionalization, namely: in situ synthesis and adsorption through filtration. NPs optimal concentration and functionalization process will be examined and tailored to obtain a BNC AH mesh with effective antimicrobial activity and negligible cytotoxicity. According the AH implantation site, three different hernia meshes classes are usually applied: low, medium and high weight, thus the optimal antimicrobial BNC meshes of each class will be patented to represent a viable commercial alternative, by displaying superior mechanical properties, biocompatibility and low infection propensity, to considerably improve AH patience overall wellbeing.FEDER funds under the COMPETE program and by National Funds through Fundação para a Ciência e Tecnologia (FCT) under the project POCI-01- 0145-FEDER-007136 and UID/CTM/00264/2013. PLASMAMED project PTDC/CTMTEX/28295/2017 funded by FCT, FEDER e POCI through the program Portugal 202

Pesquisa de leucócitos residuais

A presença de leucócitos nos concentrados de eritrócitos (CE) e nos concentrados de plaquetas (CP) está associada a uma maior incidência de reacções febris, com transmissão de citomegalovírus (CMV) e aloimunização a antigénios HLA em indivíduos transfundidos. A exigência de componentes sanguíneos pobres em leucócitos implica a existência de um controlo relativamente à persistência dos leucócitos residuais. As amostras foram adquiridas no citómetro de fluxo e analisadas mediante um programa informático. A citometria de fluxo permite quantificar os leucócitos residuais dos diferentes componentes sanguíneos, avaliando a conformidade ou não conformidade com as normas exigidas pelo conselho da Europa

Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light

Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one of the methods used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using tryptic soy broth (TSB) or TSB with 1 % sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37 °C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (P < 0.05) decrease compared to the non-treated groups after the 2 or 6 h recovery period. Growth rates of planktonic and biofilm cells indicated a significant reduction in the growth rate of the violet-blue light-treated groups grown in TSB and TSBS. Biofilm viability assays confirmed a statistically significant difference between violet-blue light-treated and non-treated groups in TSB and TSBS. Visible violet-blue light of the electromagnetic spectrum has the ability to inhibit S. mutans growth and reduce the formation of S. mutans biofilm. This in vitro study demonstrated that violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries

Social capital and self-rated health among adolescents in Brazil: an exploratory study

<p>Abstract</p> <p>Background</p> <p>Social capital may influence health and the patterns of association differ according its dimension such as cognitive, behavioral, bridging or bonding. There is a few numbers of studies in Latin America which comprise these aspects of social capital and health. The aim of this study was to examine the association between social capital and self-rated health among youth, and distinguish between the different forms of social capital - cognitive versus behavioral, and bonding versus bridging.</p> <p>Findings</p> <p>A cross-sectional study was conducted in 2009 among working adolescents supported by a Brazilian NGO. The sample comprised 363 individuals and data were collected using a validated structured questionnaire. The outcome, self-rated health, was measured as a dichotomous variable (poor/good health) and fourteen social capital indicators were investigated (cognitive, behavioral and bonding/bridging). Data were analyzed using multivariate logistic regression. Cognitive (social support and trust), behavioral (civic participation) and bridging social capital were associated with good self-rated health after adjustment of all the other social capital indicators and confounders (sex, age, skin color and educational background).</p> <p>Conclusions</p> <p>Social capital was associated with self-rated health and the patterns of association differed according its specific dimensions. Cognitive, behavioral and bridging social capitals were protective for adolescents health living in a developing country context..</p

Antimicrobial performance of lignin embedded in bacterial nanocellulose membranes

The development of bio-based antimicrobial polymeric composites has never been so urgent. Novel antimi- crobial fibrous-based biocomposites will certainly allow the development of important solutions to fight the present and future Pandemics, while reducing the dependence of petrochemical based polymers and fibers. Lignin has a pivotal function in preventing the invasion of phytopathogens, thus, this work explores the anti- microbial potential of lignin when embedded in a biosynthesized fibrous nanomatrix with superior mechanical properties: bacterial nanocellulose (BNC). Lignin was subjected to alkali treatment to promote the inclusion of lignin within BNC which comprises pores ranging from 20 to 300 nm. Both alkali treatment efficiency, bac- tericidal and antiviral activities were investigatedThe authors would like to acknowledge the project PLASMAMED - PTDC/CTM-TEX/28295/2017 fnanced by FCT, FEDER and POCI in the frame of the Portugal 2020 program, the project UID/CTM/00264/2019 of 2C2T under the COMPETE and FCT/MCTES (PIDDAC) co-fnanced by FEDER through the PT2020 program. Liliana Melro acknowledges her Doctoral grant awarded by FCT (2020.04919.BD)

Antibacterial properties of bacterial nanocellulose functionalized with metal nanoparticles via in situ synthesis

[Excerpt] Wound infections are generally caused by pathogens and multidrug-resistant (MDR) strains that render the administration of antibiotics ineffective. An alternative is to treat infected wounds at the initial stage using a fibrous bionanopolymer, bacterial nanocellulose (BNC), functionalized with antimicrobial metal nanoparticles (MNPs). BNC is a highly promising wound dressing due to its very high-water retention capacity (> 99 %) and high porosity. Such properties enable the absorbance of exudates, whilst maintaining the environment moist allowing the exchange of air. However, BNC is absent of antibacterial properties, thus gold (Au), copper (Cu), and copper oxide (Cu2O) NPs were incorporated within the nanofibrous structure of the biopolymer via in situ synthesis

Synergistic activity of a novel class of azoimidazole dyes with polyvinylpyrrolidone-silver nanoparticles for the development of antibacterial textiles

The high demand for novel antimicrobial textiles by the medical, health care, hygiene, sportswear, personal protective equipment, and filtration sectors promoted the growth of functional textiles. However, the efficacy of antimicrobial agents against different pathogens is a considerable challenge due to the distinctive mechanisms of action and resistance. The development of novel synergistic antimicrobial agents may offer numerous opportunities to enhance antimicrobial effectiveness, namely boost the activity of individual agents, reduce dosages, minimize toxicity, and amplify the activity spectrum. On the one hand, azo dyes containing a heterocycle present good tinctorial strength and brightness of shades. In particular, the imidazole ring also has interesting antimicrobial, analgesic, and anti-inflammatory properties. On the other hand, silver nanoparticles (AgNPs) are renowned antimicrobial agents against a wide range of microorganisms, but their application is limited by the toxicity observed for effective concentrations. In this work, a novel class of azoimidazoles (AzoIz) and corresponding precursors (AmIz) were conjugated with polyvinylpyrrolidone-coated AgNPs, and their synergistic effect was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results showed interesting antimicrobial properties of the novel AzoIz molecules when combined with a very small concentration of AgNPs. Thus, the application of these conjugates in textiles may lead to highly colored materials with remarkable antimicrobial properties, which worth to be further explored

Phytochemical composition and bioactive effects of Salvia africana, salvia officinalis 'Icterina' and Salvia mexicana aqueous Extracts

In the present study, aqueous extracts of Salvia africana, Salvia o cinalis ‘Icterina’ and Savia mexicana origin were screened for their phenolic composition and for antibacterial, antioxidant, anti-inflammatory and cytotoxic properties. The three aqueous extracts contained distinct phenolic compounds, with S. africana presenting the highest total levels (231.6 7.5 g/mg). Rosmarinic acid was the dominant phenolic compound in all extracts, yet that of S. africana origin was characterized by the present of yunnaneic acid isomers, which overall accounted for about 40% of total phenolics. In turn, S. o cinalis ‘Icterina’ extract presented glycosidic forms of apigenin, luteolin and scuttelarein, and the one obtained from S. mexicana contained several simple ca eic acid derivatives. S. africana aqueous extract exhibited high antioxidant potential in four methods, namely the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging ability, iron-reducing power, inhibition of -carotene bleaching and of thiobarbituric acid reactive substances (TBARS), for which EC50 values were equal or only 1.3–3.1 higher than those of the standard compounds. Moreover, this extract was able to lower the levels of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages (EC50 = 47.8 2.1 g/mL). In addition, the three sage aqueous extracts showed promising cytotoxic e ect towards hepatocellular HepG2, cervical HeLa, and breast carcinoma cells MCF-7. Overall this study highlights the potential of three little-exploited Salvia species, with commercial value for applications in food or pharmaceutical industries.Foundation for Science and Technology (FCT), the European Union, the National Strategic Reference Framework (QREN), the European Regional Development Fund (FEDER), and Operational Programme Competitiveness Factors (COMPETE), for funding the Organic Chemistry Research Unit (QOPNA) (FCT UID/QUI/00062/2019) and Mountain Research Center (CIMO) (UID/AGR/00690/2019), through national funds and where applicable co-financed by the FEDER, within the PT2020 Partnership Agreement. A. Fernandes and R. Calhelha thank the national funding by FCT, P.I., through the institutional scientific employment program-contract. Project AgroForWealth (CENTRO-01–0145-FEDER-000001), funded by Centro2020, through FEDER and PT2020, financed the research contract of Susana M. Cardoso. APC was sponsored by MDPI.info:eu-repo/semantics/publishedVersio