Essential oils encapsulated in zeolite structures as delivery systems (EODS): an overview

Essential oils (EO) obtained from plants have proven industrial applications in the manufacturing of perfumes and cosmetics, in the production and flavoring of foods and beverages, as therapeutic agents in aromatherapy, and as the active principles or excipients of medicines and pharmaceutics due to their olfactory, physical-chemical, and biological characteristics. On behalf of the new paradigm of a more natural and sustainable lifestyle, EO are rather appealing due to their physical, chemical, and physiological actions in human beings. However, EO are unstable and susceptible to degradation or loss. To tackle this aspect, the encapsulation of EO in microporous structures as zeolites is an attractive solution, since these host materials are cheap and non-toxic to biological environments. This overview provides basic information regarding essential oils, including their recognized benefits and functional properties. Current progress regarding EO encapsulation in zeolite structures is also discussed, highlighting some representative examples of essential oil delivery systems (EODS) based on zeolites for healthcare applications or aromatherapy.The authors are grateful for the national funds provided by the FCT (Foundation for Science and Technology, Portugal) under the projects UIDB/04050/2020 (CBMA) and PTDC/AAGTEC/5269/2014 (FEDER, European Fund for Regional Development)/COM PETE/POCI—Operational Competitiveness and Internationalization Programme under the project POCI-01-0145-FEDER-006958. They are grateful for the financial support provided by the Research Centers CQ/UM through UID/QUI/0686/2020 and Project BioTecNorte (operation NORTE-01-0145-FEDER-000004), supported by the Northern Portugal Regional Operational Programme (NORTE 2020) under the Portugal 2020 Partnership Agreement through the European Regional Development Fund.info:eu-repo/semantics/publishedVersio

Optimizing dual energy cone beam CT protocols for preclinical imaging and radiation research

Objective: The aim of this work was to investigate whether quantitative dual-energy CT (DECT) imaging is feasible for small animal irradiators with an integrated cone-beam CT (CBCT) system. Methods: The optimal imaging protocols were determined by analyzing different energy combinations and dose levels. The influence of beam hardening effects and the performance of a beam hardening correction (BHC) were investigated. In addition, two systems from different manufacturers were compared in terms of errors in the extracted effective atomic numbers (Z(eff)) and relative electron densities (rho(e)) for phantom inserts with known elemental compositions and relative electron densities. Results: The optimal energy combination was determined to be 50 and 90kVp. For this combination, Z(eff) and r rho(e) can be extracted with a mean error of 0.11 and 0.010, respectively, at a dose level of 60cGy. Conclusion: Quantitative DECT imaging is feasible for small animal irradiators with an integrated CBCT system. To obtain the best results, optimizing the imaging protocols is required. Well-separated X-ray spectra and a sufficient dose level should be used to minimize the error and noise for Z(eff) and rho(e). When no BHC is applied in the image reconstruction, the size of the calibration phantom should match the size of the imaged object to limit the influence of beam hardening effects. No significant differences in Z(eff) and rho(e) errors are observed between the two systems from different manufacturers. Advances in knowledge: This is the first study that investigates quantitative DECT imaging for small animal irradiators with an integrated CBCT system

A study of the ethical dilemmas experienced by school psychologists in Portugal

Published online: 06 Apr 2015This study examines the ethical dilemmas and difficulties encountered by Portuguese school psychologists. As part of a larger survey, participants were asked about ethical issues faced in daily practice and asked to describe ethical incidents. Of the 477 respondents, 274 reported 441 ethically troubling or challenging situations. Responses were coded into a six-category system based on the code of ethics of Portuguese psychologists. Most of the reported dilemmas concerned privacy and confidentiality principles (53%). Results are discussed in light of relevant literature and international findings. Implications for the development of the profession and future research are provided.This research was financially sponsored by the Portuguese Foundation for Science and Technology (Doctoral grant, SFRH/BD/78646/2011)

A study of the antitumour potential of three Portuguese wild mushrooms

Natural matrixes such as mushrooms represent a rich source of biologically active compounds with recognized potential in drug discovery and development [1,2]. Indeed, many pre-clinical studies have been conducted in human tumour cell lines and in some cases, a number of compounds extracted from mushrooms have entered clinical trials [3]. Our previous results showed that extracts from Agaricus arvensis, Suillus collinitus and Clytocibe alexandri are promising sources of low molecular weight bioactive compounds [4]. The aim of the present work was to study the antitumour potential of the extracts and isolated compounds from three Portuguese wild mushrooms by verifying their effect on various human tumour cell lines in what concerns effect on cell growth, cell cycle profile and programmed cell death. Wild mushrooms were collected from the Northeast of Portugal and classified as Agaricus arvensis, Suillus collinitus and Clitocybe alexandri. Phenolic (methanolic and ethanolic) and polissacharidic extracts were prepared. The effect of the extracts on tumour cell growth inhibition was verified with the SRB assay and the GI50 of each extract was determined for each of the cell lines studied (NCI-H460, MCF-7, AGS and HCT-15). Our preliminary results revealed that all the extracts from Clitocybe alexandri are capable of causing cell growth inhibition and provided GI50 concentrations bellow 60µg/ml in all the cell lines tested [4]. Regarding the effect of the Agaricus arvensis extracts, they all caused an inhibition of cell growth in all cell lines, particularly the methanolic extract which revealed to be a very potent inhibitor of cell growth, especially in the MCF-7 cell line. The evaluation of the effect of the Suillus collinitus extracts will be carried out as well as cell cycle and apoptosis analyses, by flow cytometry. Finally, the isolation and characterization of compounds from these extracts will also be carried out, using HPLC-DAD or HPLC-RI. The structures of the compounds will be established by NMR spectral analysis (1H, 13C, DEPT, COSY, HSQC and HMBC).FCT and COMPETE/QREN/UE- project PTDC/AGR-ALI/110062/200

Effects of wastewater treatment plant’s discharges on a freshwater ecosystem—a case study on the Ramalhoso River (Portugal)

Sewage discharges constitute severe stress in freshwater ecosystems. The Ramalhoso River belongs to the Tagus river watershed and was chosen for a pilot study on the impact of wastewaters discharges in a freshwater ecosystem and its ability for self-depuration. Twelve water samples were collected along the river and were georeferenced. The first point is located upstream of the first discharge point, the second one corresponding to the discharge flow, and all the other samples located downstream of secondary inflows at approximately equal distances. Three sampling campaigns were conducted during the rainy winter (January), the intermediate conditions (March), and the dry season (June). The following chemical parameters were analyzed: Biochemical Oxygen Demand (5), Dissolved Oxygen concentration (DO), Ptotal, Ntotal, pH, temperature, total suspended solids (TSS), microbiological parameters (MP), and flow determination. Dissolved oxygen (DO), biochemical oxygen demand, for 5 days (BOD5), and the total suspended solids were used as indicators of environmental pollution. A coupled hydrodynamic and water dispersion model simulated different pollution scenarios using the QUAL2kw software to construct a water quality model. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated, allowing feasibility studies of different treatment schemes and the development of specific monitoring activities.Águas do Centro Enterprise and by the Institute of Earth Sciences (ICT), under contracts UID/GEO/04683/2013 with FCT (Portuguese Science and Technology Foundation

TGGE-monitoring of the microbial community along the olive mill wastewaters anaerobic treatment

Monitoring the microbial community present during the olive mill wastewater (OMW) anaerobic treatment was carried out using PCR-TGGE analysis. Phase-contrast microscopy was used in order to directly examine microbial cells morphology. Samples were collected from the anaerobic digester bottom along the successive increases of OMW loading rate. TGGE banding patterns showed a significant diversity of OTUs. Cluster analysis of TGGE banding patterns shows two major groups: one cluster composed of samples belonging to the initial phases of treatment and a second cluster that encloses the other two samples. According to BLAST results, four sequences affiliated with group Cytophaga-Flexibacter-Bacteroidetes (CFB), one with sub-class Epsilon-Proteobacteria and other with phylum Firmicutes. The sequences obtained from each band were used to construct phylogenetic trees, and also using bacterial 16S rDNA sequences from environmental clones and reference taxa. Archaeal 16SrDNA PCR detection analysis revealed the presence of Archaea only in the initial sample of the digester start-up suggesting that methanogenesis along the treatment process occurs at an upper level of the unit. Concerning microscopic observations, the more representative morphological forms found in the bottom of digester were Clostridium spp. and Clostridium spp. sarcina-like forms

Study about the importance of E-fatura and IVAucher in the tourism and culture sectors in pandemic times

Since February 2015, Portuguese citizens can deduct from VAT a percentage of the expenses on their invoices. This deduction includes expenses related to accommodation, catering and similar. This action is done through the online E-fatura platform, a space where Portuguese taxpayers can check their invoices and the amounts of deductions. By encouraging taxpayers to ask for an invoice, the Portuguese Government intends to fight tax evasion and fraud and to privilege sectors of the economy such as tourism. With the pandemic caused by SARS-COV-2, the Government is preparing to launch another technological platform to put into practice another measure to support tourism called IVAucher and which it presented in the State Budget for 2021. This temporary measure will allow citizens accumulate VAT on consumption in restaurants, hotels and culture, in vouchers that can be discounted in the following quarter on new consumption in the same activities. This study aims to present the opinion of the Portuguese about these measures. A national survey was carried out through an electronic survey to understand whether the Portuguese know the measures and whether they use or intend to use it, and to know their opinion about the impact of this on the consumption of products and services related to the tourism and culture sector. The results show an overall positive view of these measures, although they do not seem, by themselves, to induce significant changes in consumer’s behaviours. The study also makes clear the need for further research on the interplay between these measures and other public policies being implemented, particularly those focused on the stimulus of the demand.info:eu-repo/semantics/publishedVersio

Processing of tetrahedrite-based thermoelectric materials using tetrahedrite-tennantite copper ores

ABSTRACT: Tetrahedrite-based compounds are considered a promising thermoelectric material. The tetrahedrite-tennantite series, that can be generically expressed as Cu6[Cu4(Fe,Zn)2](Sb,As)4S13, is one of the most abundant sulfosalt minerals in the earth’s crust. The Iberian Pyrite Belt (IPB), located in southern Portugal and Spain, is the host of the largest concentration of massive sulfide deposits worldwide, where the tetrahedrite-tennantite series mineral is one of the constituents. In this work we evaluate the effectiveness of combining synthetic tetrahedrite (ST) with tetrahedritetennantite ore samples (TTOS) in the mechanochemical synthesis (MCS) process of tetrahedrite based compounds. The ore samples were collected from two distinct deposits within the Portuguese part of the IPB, the Neves Corvo mine and the abandoned Barrigão copper mine. The ST, also produced by MCS, were mixed with the TTOS in different mass ratios ranging from 20-80%. The influence of the chemical composition and phase constitution of the ore samples and of the mixing ratios will be presented in relation to the micro-structural properties of the obtained materials. The results here described are part of a broader study dedicated to the development of energy-harvesting applications based on tetrahedrite.info:eu-repo/semantics/publishedVersio

Operational research IO 2021—analytics for a better world. XXI Congress of APDIO, Figueira da Foz, Portugal, November 7–8, 2021

This book provides the current status of research on the application of OR methods to solve emerging and relevant operations management problems. Each chapter is a selected contribution of the IO2021 - XXI Congress of APDIO, the Portuguese Association of Operational Research, held in Figueira da Foz from 7 to 8 November 2021. Under the theme of analytics for a better world, the book presents interesting results and applications of OR cutting-edge methods and techniques to various real-world problems. Of particular importance are works applying nonlinear, multi-objective optimization, hybrid heuristics, multicriteria decision analysis, data envelopment analysis, simulation, clustering techniques and decision support systems, in different areas such as supply chain management, production planning and scheduling, logistics, energy, telecommunications, finance and health. All chapters were carefully reviewed by the members of the scientific program committee.info:eu-repo/semantics/publishedVersio