Design, Characterization and Biological Properties

Funding Information: This work was financed by national funds from FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of projects UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO, the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB, project UIDP/04129/2020 of LEAF—Linking Landscape, Environment, Agriculture and Food—Research Center, and projects LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication—i3N. Diana Araújo and Catarina Roma-Rodrigues were funded by FCT/MCTES, with grant numbers SFRH/BD/140829/2018 and SFRH/BPD/124612/2016, respectively. Publisher Copyright: © 2023 by the authors.FucoPol, a fucose-rich polyanionic polysaccharide, was used for the first time for the preparation of hydrogel membranes (HMs) using Fe3+ as a crosslinking agent. This study evaluated the impact of Fe3+ and FucoPol concentrations on the HMs’ strength. The results show that, above 1.5 g/L, Fe3+ concentration had a limited influence on the HMs’ strength, and varying the FucoPol concentration had a more significant effect. Three different FucoPol concentrations (1.0, 1.75 and 2.5 wt.%) were combined with Fe3+ (1.5 g/L), resulting in HMs with a water content above 97 wt.% and an Fe3+ content up to 0.16 wt.%. HMs with lower FucoPol content exhibited a denser porous microstructure as the polymer concentration increased. Moreover, the low polymer content HM presented the highest swelling ratio (22.3 ± 1.8 g/g) and a lower hardness value (32.4 ± 5.8 kPa). However, improved mechanical properties (221.9 ± 10.2 kPa) along with a decrease in the swelling ratio (11.9 ± 1.6 g/g) were obtained for HMs with a higher polymer content. Furthermore, all HMs were non-cytotoxic and revealed anti-inflammatory activity. The incorporation of FucoPol as a structuring agent and bioactive ingredient in the development of HMs opens up new possibilities for its use in tissue engineering, drug delivery and wound care management.publishersversionpublishe

Poly(ionic liquid)-based engineered mixed matrix membranes for CO2/H2 separation

Unformatted preprintPoly(ionic liquid)s (PIL) have emerged as a class of versatile polyelectrolites, that can be used to prepare new materials able to achieve superior performances compared to conventional polymers. The combination of PILs with ionic liquids (ILs) may serve as a suitable matrix for the preparation of membranes for gas separation. In this work, mixed matrix membranes (MMMs) combining a pyrrolidinium-based PIL, an IL and three highly CO2-selective metal organic frameworks (MOFs) were prepared. The different MOFs (MIL-53, Cu3(BTC)2 and ZIF-8) were used as fillers, aiming to maximize the membranes performance towards the purification of syngas. The influence of different MOFs and loadings (0, 10, 20 and 30 wt.%) on the thermal and mechanical stabilities of the membranes and their performance in terms of CO2 permeability and CO2/H2 ideal selectivity was assessed. The compatibility between the materials was confirmed by SEM-EDS and FTIR spectroscopy. The prepared MMMs revealed to be thermally stable within the temperature range of the syngas stream, with a loss of mechanical stability upon the MOF incorporation. The increasing MOF content in the MMMs, resulted in an improvement of both CO2 permeability and CO2/H2 ideal selectivity. Among the three MOFs studied, membranes based on ZIF-8 showed the highest permeabilities (up to 97.2 barrer), while membranes based on MIL-53 showed the highest improvement in selectivity (up to 13.3). Remarkably, all permeation results surpass the upper bound limit for the CO2/H2 separation, showing the membranes potential for the desired gas separation.This work was partially supported by R&D Units UID/Multi/04551/2013 (Green-it), UID/QUI/00100/2013 (CQE), and the Associated Laboratory Research Unit for Green Chemistry, Technologies and Clean Processes, LAQV which is financed by national funds from FCT/MCTES(UID/QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265). Ana R. Nabais, Luísa A. Neves and Liliana C. Tomé acknowledge FCT/MCTES for financial support through project PTDC/CTM-POL/2676/2014, FCT Investigator Contract IF/00505/2014 and Post-doctoral research grant SFRH/BDP/101793/2014, respectively. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 745734

Infinitely Many Stochastically Stable Attractors

Let f be a diffeomorphism of a compact finite dimensional boundaryless manifold M exhibiting infinitely many coexisting attractors. Assume that each attractor supports a stochastically stable probability measure and that the union of the basins of attraction of each attractor covers Lebesgue almost all points of M. We prove that the time averages of almost all orbits under random perturbations are given by a finite number of probability measures. Moreover these probability measures are close to the probability measures supported by the attractors when the perturbations are close to the original map f.Comment: 14 pages, 2 figure

Pollution prevention and wastewater treatment in fish canning industries of Northern Portugal

The main environmental problems of fish canning industries are high water consumption and high organic matter, oil and grease and salt content in their wastewaters. This work aims to analyze the situation (water consumption, wastewater production, wastewater characterization, etc.) of different plants located north of Douro river, in Portugal, in order to propose various solutions to their problems. Thus, initially it was made an identification and implementation of prevent and control pollution measures within the industrial units in order to reduce water consumption, minimize the wastewater production and reduce the pollutant load to treat. Then, the evaluation of wastewater treatability was started through a sedimentation and coagulation-flocculation process, with two organic coagulants (RIPOL 070 and RIFLOC 1815), commonly used in wastewater treatment. Sedimentation experiments showed that the flotation of 54% of oils and greases occurred, and 36% of total suspended solids were removed. The coagulation-flocculation process gave good results, especially in terms of oil and grease and total suspended solids removal. The best suspended solids removal efficiencies were 53% and 79%, using 400 mg/L of RIPOL 070 and 150 mg/L of RIFLOC 1815, respectively. At these dosages, both coagulants demonstrated excellent oil and grease removals, about 99% for RIFLOC 1815 and 88% for RIPOL 070info:eu-repo/semantics/publishedVersio

Stochastic stability at the boundary of expanding maps

We consider endomorphisms of a compact manifold which are expanding except for a finite number of points and prove the existence and uniqueness of a physical measure and its stochastical stability. We also characterize the zero-noise limit measures for a model of the intermittent map and obtain stochastic stability for some values of the parameter. The physical measures are obtained as zero-noise limits which are shown to satisfy Pesin?s Entropy Formula

Characterisation of Films Based on Exopolysaccharides from Alteromonas Strains Isolated from French Polynesia Marine Environments

LA/P/0140/202019 UID/AGR/04129/2020 LA/P/0037/2020This work assessed the film-forming capacity of exopolysaccharides (EPS) produced by six Alteromonas strains recently isolated from different marine environments in French Polynesia atolls. The films were transparent and resulted in small colour alterations when applied over a coloured surface (ΔEab below 12.6 in the five different colours tested). Moreover, scanning electron microscopy showed that the EPS films were dense and compact, with a smooth surface. High water vapour permeabilities were observed (2.7–6.1 × 10−11 mol m−1 s−1 Pa−1), which are characteristic of hydrophilic polysaccharide films. The films were also characterised in terms of barrier properties to oxygen and carbon dioxide. Interestingly, different behaviours in terms of their mechanical properties under tensile tests were observed: three of the EPS films were ductile with high elongation at break (ε) (35.6–47.0%), low tensile strength at break (Ꞇ) (4.55–11.7 MPa) and low Young’s modulus (εm) (10–93 MPa), whereas the other three were stiffer and more resistant with a higher Ꞇ (16.6–23.6 MPa), lower ε (2.80–5.58%), and higher εm (597–1100 MPa). These properties demonstrate the potential of Alteromonas sp. EPS films to be applied in different areas such as biomedicine, pharmaceuticals, or food packaging.publishersversionpublishe

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Application of an Eco-Friendly Antifungal Active Package to Extend the Shelf Life of Fresh Red Raspberry (Rubus idaeus L. cv. ‘Kweli’)

The main objective of this study was to extend the shelf life of fresh red raspberry (Rubus idaeus. L. cv. ‘Kweli’) by using active film-pads inside commercial compostable packages. The pads were produced with chitosan (Ch) with the incorporation of green tea (GTE) and rosemary (RSME) ethanolic extracts as natural antifungal agents. Pads were placed on the bottom of commercial fruit trays underneath the fruits, and the trays were heat-sealed with a polyacid lactic (PLA) film. Preservation studies were carried out over 14 days of storage at refrigeration temperature (4 °C). Raspberry samples were periodically analyzed throughout storage, in terms of quality attributes (fungal decay, weight loss, firmness, surface color, pH, total soluble solids), total phenolic content and antioxidant activity. Gas composition inside the packages was also analyzed over time. From the packaging systems tested, the ones with active film-pads Ch + GTE and Ch + RSME were highly effective in reducing fungal growth and decay of raspberry during storage, showing only around 13% and 5% of spoiled fruits after 14 days, respectively, in contrast with the packages without pads (around 80% of spoiled fruits detected). In addition, fruits preserved using packages with Ch + RSME active film-pads showed lower mass loss (5.6%), decreased firmness (3.7%) and reduced antioxidant activity (around 9% and 15% for DPPH and FRAP methods, respectively). This sustainable packaging presents a potential strategy for the preservation of raspberries and other highly perishable small fruits

Development of cellulose-based polymeric structures using dual functional ionic liquids

Funding Information: This work was supported by the Associate Laboratory for Green Chemistry – LAQV which is nanced by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020); Linking Landscape, Environment, Agriculture and Food Research Centre (LEAF), which is nanced by national funds from FCT/ MCTES (UID/AGR/04129/2020) and the national project “PTDC/ CTM-CTM/29869/2017”, which is nanced by Fundação para a Ciência e a Tecnologia (FCT). The NMR spectrometers are part of The National NMR Facility, supported by FCT/MCTES (RECI/ BBB-BQB/0230/2012). Funding Information: NMR spectra were done on a Bruker AMX 400 instrument operating at 400.13 MHz (1H), 100.61 MHz (13C). The NMR spectrometers are part of The National NMR Facility supported by Fundação para a Ciência e a Tecnologia (RECI/BBB-BQB/0230/2012). Publisher Copyright: © The Royal Society of Chemistry 2021.Carboxylate ionic liquids (ILs) combining benzethonium (BE) and didecyldimethylammonium (DDA) as cations have been explored to be used for the first time as dual functional solvents for microcrystalline cellulose (MCC) dissolution and, subsequently development of polymeric structures. Considering that some ILs can remain in the polymeric structures after phase inversion, these ILs can offer advantages such as antibacterial/antimicrobial response and ability to disrupt H-bonds. In this context, all tested ILs have been able to dissolve MCC up to a concentration of 4% (w/w), resulting in different polymeric structures, such as gel-like or films, depending on the type of IL and the ratio between MCC and IL. Furthermore, FTIR spectroscopy showed that some IL remains in the polymeric structures, which can enhance their application in the biomedical field.publishersversionpublishe