Proton conductivity of Nafion-azolebisphosphonates membranes for PEM fuel cells

Energy systems with cleaner and sustainable sources are crucial challenges of the 21st century to deal with the environmental threat of global warming and the declining reserves of fossil fuels. Fuel cells are electrochemical devices that convert the chemical energy stored in a fuel directly into electrical energy, providing electrical energy with high efficiency and low environmental impact. Among them, proton exchange membrane fuel cells (PEMFCs) are considered promising power sources, due to their high power density and high power-to-weight ratio but their performance depends crucially on their proton exchange membranes [1]. Usually, these membranes are made of organic polymers containing acidic functionalities (ex. Nafion® ), which proton transport properties strongly depend on their water content and, consequently, limit their operation temperatures up to 90ºC. Preliminary studies have demonstrated that incorporation of aryl-bisphosphonic acids into Nafion, by casting, results in an enhancement of the proton conductivity of the membrane. The aim of this work was the preparation of new Nafion membranes doped with azolebisphosphonates derivatives, which could act as a source of protons and also function as proton acceptors, facilitating the intermolecular transmission of protons through the membrane

Cyclic deformation of bidisperse two-dimensional foams

In-plane deformation of foams was studied experimentally by subjecting bidisperse foams to cycles of traction and compression at a prescribed rate. Each foam contained bubbles of two sizes with given area ratio and one of three initial arrangements: sorted perpendicular to the axis of deformation (iso-strain), sorted parallel to the axis of deformation (iso-stress), or randomly mixed. Image analysis was used to measure the characteristics of the foams, including the number of edges separating small from large bubbles N-sl, the perimeter (surface energy), the distribution of the number of sides of the bubbles, and the topological disorder mu(2)(N). Foams that were initially mixed were found to remain mixed after the deformation. The response of sorted foams, however, depended on the initial geometry, including the area fraction of small bubbles and the total number of bubbles. For a given experiment we found that (i) the perimeter of a sorted foam varied little; (ii) each foam tended towards a mixed state, measured through the saturation of N-sl; and (iii) the topological disorder mu(2)(N) increased up to an "equilibrium" value. The results of different experiments showed that (i) the change in disorder, Delta mu(2)(N), decreased with the area fraction of small bubbles under iso-strain, but was independent of it under iso-stress; and (ii) Delta mu(2)(N) increased with Delta N-sl under iso-strain, but was again independent of it under iso-stress. We offer explanations for these effects in terms of elementary topological processes induced by the deformations that occur at the bubble scale

Novel 1-hydroxy-1,1-bisphosphonates derived from indazole: synthesis and characterization

Bisphosphonates (BPs) are an important class of drugs used in the treatment of abnormal calcium metabolism diseases. The first syntheses of bisphosphonates derived from indazole, substituted at the N-1, N-2 and C-3 positions are reported. The 1-hydroxy-1,1-bisphosphonates were synthesized from the corresponding carboxylic acid or acyl chloride compounds, by two different methods. These BPs have a side chain with different lengths ((CH2)n, n = 0-5) between the indazole ring and the bisphosphonate group

PRÉ-HABILITAÇÃO E PROGNÓSTICO PÓS-OPERATÓRIO EM DOENTES ONCOLÓGICOS DE ALTO RISCO: UMA REVISÃO SISTEMÁTICA E META-ANÁLISE

Introduction. Prehabilitation aims to optimize patients before surgical treatment in order to improve postsurgical recovery. While its efficacy to improve major postoperative clinical outcomes have been recognized for the broader low-risk surgical population, it remains unclear if the high-risk surgical population also benefits. This meta-analysis assessed the impact of prehabilitation on postoperative outcomes in high-risk surgical cancer patients Methodology: We searched for experimental (randomized and non- randomized) and observational studies investigating the impact of prehabilitation in the frequency and/or severity (e.g minor and major complications) of post-surgical complications (primary outcome), type of complications, functional capacity, hospital readmissions, length of hospital stay and 30 day post-surgical mortality (secondary outcomes). High-risk patients for adverse surgical events were defined as frail and / or age ≥70 years and / or with an ASA score of >III. Results: 136 articles were found, of which only 6 were eligible for qualitative and quantitative evaluation (3 randomized and 3 observational studies). The analysis resulted in a total of 674 participants, with an average age of 78 years, mostly male. Prehabilitation resulted in a lower risk of major complications (risk difference –0.09, 95% CI: –0.15, – 0.03, p = 0.005; i2 = 27%, p = 0.24) and surgical complications (RR 0.62, 95% CI 0.43 to 0.89, p=0.01; I2 = 33%, p = 0.22) in comparison to patients receiving standard care. Also, prehabilitation reduced the length of hospital stay (mean difference of – 2.7, 95% CI: –5.37 to –0.17, p = 0.04) and improved functional recovery as assessed by the distance covered in the 6 MWT (mean difference 29.06 meters, 95% CI 26.55 to 31.57, I2 = 42%, p < 0.001). No differences were observed for the rate of overall complications, medical complications 30-day postoperative mortality or hospital readmission. Conclusion: Our work suggests that prehabilitation is effective in reducing postoperative burden in high-risk cancer patients. Future randomized controlled trials for the high-risk surgical patients, using well-established and clinically relevant outcome measures, and with appropriate sample size calculation are needed.Introdução: A pré-habilitação visa otimizar os doentes antes do tratamento cirúrgico, com o objetivo de melhorar a sua recuperação pós-cirúrgica. Embora a eficácia desta intervenção para melhorar os principais desfechos clínicos pós-operatórios tenha sido reconhecida para a população cirúrgica de baixo risco, ainda não está claro até que ponto estes benefícios serão extensíveis também para doentes considerados de alto risco. Esta meta-análise avaliou o impacto da pré-habilitação em desfechos pós-operatórios de doentes oncológicos cirúrgicos de alto risco. Metodologia: Procuramos estudos experimentais (randomizados e não randomizados) e observacionais que avaliaram o impacto da pré-habilitação na frequência e / ou gravidade (major e minor) das complicações pós-cirúrgicas (desfecho primário), tipo de complicações, capacidade funcional, readmissões hospitalares, tempo de hospitalização e mortalidade pós-cirúrgica até 30 dias (desfechos secundários). Doentes de alto risco para eventos cirúrgicos adversos foram definidos como frágeis e / ou com idade ≥70 anos e / ou com score ASA> III. Resultados: foram encontrados 136 artigos, dos quais apenas 6 foram elegíveis para avaliação qualitativa e quantitativa (3 estudos randomizados e 3 estudos observacionais). A análise global incluiu um total de 674 participantes, com idade média de 78 anos, a maioria do sexo masculino. A pré-habilitação reduziu o risco de complicações major (diferença do risco –0,09, IC 95%: –0,15, – 0,03, p = 0,005; i2 = 27%, p = 0,24) e de complicações cirúrgicas (RR 0,62, IC 95% 0,43 a 0,89, p = 0,01; I2 = 33%, p = 0,22) em comparação com doentes que receberam o tratamento habitual. Além disso, a pré-habilitação reduziu o tempo de hospitalização (diferença média de – 2,7, IC 95%: –5,37 a –0,17, p = 0,04) e melhorou a recuperação funcional avaliada pela distância percorrida no teste de marcha de 6 minutos (diferença média de 29,06 metros, IC de 95% 26,55 a 31,57, I2 = 42%, p <0,001). Não foram observadas diferenças para as complicações gerais, complicações médicas, mortalidade pós-operatória até 30 dias ou na readmissão hospitalar. Conclusão: O nosso trabalho sugere que a pré-habilitação é eficaz na melhoria do prognóstico pós-operatório de doentes oncológicos considerados de “alto risco” para complicações cirúrgicas. Ficou evidente a necessidade de desenvolver ensaios clínicos randomizados especialmente focados em doentes cirúrgicos de alto risco, usando medidas de desfecho bem estabelecidas e clinicamente relevantes, e com cálculo de tamanho amostral adequado

Improving antibiotic use through educational interventions

The growing rates of antimicrobial resistances demand the improvement of antibiotic use worldwide. The antibiotic misprescription by physicians, the antibiotic dispense without prescription by pharmacists, and the misuse by patients, are some of the most important factors underlying the increasing rates of antimicrobial resistances. Accordingly, it is of major importance to develop educational interventions targeting the different actors in the chain of antibiotic resistance, aiming to increase knowledge, understand attitudes and improve antibiotic use. In this chapter, readers can find a proposed design model which aims to improve the effectiveness of the educational interventions, presenting and developing each step that should be considered when implementing an educational intervention

New Proton Conductive Heteroaromatic Bisphosphonic acid-Nafion Membranes for PEMFC

The integration of new cleaner, renewable and environment-friendly sources and energy vectors for sustainable energy systems are a key challenge for 21st century society. Fuel cells are among the clean energy conversion technologies with vast applications and scope, introducing hydrogen as a flexible and storable energy vector and presenting a viable alternative to fossil fuels. Proton exchange membrane fuel cells (PEMFCs) are considered promising power sources, but their performance depends crucially on the properties of their proton exchange membranes (PEM). These membranes strongly depend on the presence of conducting water or other electrolyte content, which limits their operation to 80 ºC. In order to advance novel membranes for application in PEMFCs, we have developed a series of bisphosphonic acid derivatives, which are used as dopants. Herein, we present the preparation and characterization of the new Nafion doped membranes, and the evaluation of their proton conductivity at different temperature and relative humidity (RH) conditions. In this work, new Nafion doped membranes were prepared and their proton conductivity were evaluated. The incorporation of BPs dopants on Nafion polymer enhances the proton conductivities of the new membranes, with all membranes showing higher proton conductivities than Nafion.“PEMFC-SUDOE” - SOE1/P1/E0293 - co-financed by the European Regional Development Fund in the framework of the Interreg SUDOE programm

New Phosphonic Acids and Esters Derived from Indazole: Synthesis and Biological Activity Evaluation

Bisphosphonates (BPs) are a group of compounds derived from bisphosphonic acid and their salts, with a P-C-P structure which confers higher metabolic and chemical stability. They are an important class of drugs with therapeutic applications in the treatment of diseases of bone mineral metabolism such as osteoporosis and Paget's disease. These compounds have also shown activity in other areas, such as antitumor and antiparasitic activities.1 The use of these compounds in therapy is affected by their low oral bioavailability due to low lipophilicity and the presence of charges at physiological pH. The improvement of their pharmacokinetic properties can be obtained by the use of ester derivatives as prodrugs.2 In this work, we present the synthesis and characterization of various phosphonic acids and esters derivatives of indazole (Figure 1). The biological activity of these compounds were evaluated including their toxicity, antioxidant and antimicrobial activities.3 Bisphosphonic acid derivatives showed broad spectra with high activity against Gram – and Gram + pathogenic and commensal bacteria. These compounds also present antioxidant activity by the β-carotene/linoleic acid method

ABIETANE DITERPENOIDS FROM PLECTRANTHUS GRANDIDENTATUS

The acetone extract of the whole plant of Plectranthus grandidentatus provided the already known abietanes royleanone, 6,7-dehydroroyleanone, horminone, 6β-hydroxyroyleanone, 7α-acetoxy-6β-hydroxyroyleanone and the abietane dimers grandidone C, grandidone D and 7-epigrandidone D, together with a mixture of fatty acid esters of 7α-acyloxy-6β,12-dihydroxy-abieta-8,12-diene-11,14-dione. Some of these compounds showed moderate antibacterial activity

Heat inactivation of Listeria innocua in broth and food products under non-isothermal conditions

The objective of this work was to study the effect of three linear temperature profiles (heating rates of 1.5, 1.8 and 2.6 °C/min, from 20 to 65 °C) on Listeria innocua inactivation in liquid medium. The inactivation was also analyzed in artificially contaminated parsley (heating rate of 1.8 °C/min) and throughout a frying process, using a pre-cooked frozen food as case study. Inactivation showed a sigmoidal behaviour and all data was fitted with a Gompertz-inspired model. Results demonstrated that, in liquid media, Listeria inactivation is influenced by the temperature profile used. As heating rate increases, the shoulder decreases and the tail effect disappears. If Listeria was in parsley, its heat resistance increased (for identical experimental conditions in broth). Besides model adequacy was proven in all studied situations, the heating rate affected parameters’ precision.info:eu-repo/semantics/acceptedVersio

Machine learning-assisted optimization of drug combinations in zeolite-based delivery systems for melanoma therapy

Two independent artificial neural network (ANN) models were used to determine the optimal drug combination of zeolite-based delivery systems (ZDS) for cancer therapy. The systems were based on the NaY zeolite using silver (Ag+) and 5-fluorouracil (5-FU) as antimicrobial and antineoplastic agents. Different ZDS samples were prepared, and their characterization indicates the successful incorporation of both pharmacologically active species without any relevant changes to the zeolite structure. Silver acts as a counterion of the negative framework, and 5-FU retains its molecular integrity. The data from the A375 cell viability assays, involving ZDS samples (solid phase), 5-FU, and Ag+ aqueous solutions (liquid phase), were used to train two independent machine learning (ML) models. Both models exhibited a high level of accuracy in predicting the experimental cell viability results, allowing the development of a novel protocol for virtual cell viability assays. The findings suggest that the incorporation of both Ag and 5-FU into the zeolite structure significantly potentiates their anticancer activity when compared to that of the liquid phase. Additionally, two optimal AgY/5-FU@Y ratios were proposed to achieve the best cell viability outcomes. The ZDS also exhibited significant efficacy against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus); the predicted combination ratio is also effective against S. aureus, underscoring the potential of this approach as a therapeutic option for cancer-associated bacterial infections.FCT - Fundação para a Ciência e a Tecnologia (UIDB/04469/2020).A.R.B. and V.I. express their gratitude to the Portuguese Foundation for Science and Technology (FCT) for providing funding through the Ph.D. Grants SFRH/BD/141058/2018 and UI/BD/152219/2021, respectively. This research work has received financial support from national funds provided by FCT/MCTES (PIDDAC) under the projects UID/QUI/0686/2020 (CQ-UM), UIDB/04469/2020 (CEB), and UIDP/50026/2020 (ICVS). Additionally, the projects of BioTecNorte (operation NORTE-01-0145-FEDER-000004 and NORTE-01-0145-FEDER-000055) are supported by the Northern Portugal Regional Operational Program (NORTE 2020) under the Portugal 2020 Partnership Agreement, cofunded by the European Regional Development Fund (ERDF). This work was also supported by the “Contrato Programa” UIDB/04050/2020 funded by national funds through the FCT I.P. The authors also thank Patrícia R. Correia for their contribution to cell viability studies