78 research outputs found

    Cost-effectiveness analysis for sustainable wastewater engineering : a case study at Minho-Lima’s rivers basins (Portugal)

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    The present work was focused on a methodological assessment for defining cost-effective measures regarding to wastewater sanitation in rural areas and was carried out within the project AQUA Project – Preliminary Studies for the Water Framework Directive Implementation at the Minho and Lima’s Rivers Basins. In order to assure a good ecological and chemical status in water bodies according to Water Framework Directive, a set of priority and complementary actions combined with a cost-effectiveness analysis was used to select a wastewater treatment strategy to increase public attendance. Using geoprocessing methodologies and geographic information multicriteria analysis (e.g.: soil, land use, topography), locations with high potential for implementation of low-energy wastewater treatment systems were identified and worked out with cost-functions. The results show that a combination of centralized and decentralized plants allow a cost-effectiveness attendance of 1,51 k¤/equivalent inhabitant in Minho and Lima’s river basins. The approach indicates that low-energy wastewater treatment plants are interesting options with a promising cost-effectiveness potential in rural areas

    Cost-effectiveness analysis for sustainable wastewater engineering and water resources management : a case study at Minho–Lima river basins (Portugal)

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    A cost-effectiveness integrated methodology applied in a water resources management and sanitation project in Minho and Lima’s region (Portugal) is presented. First, environmental objectives and programmes of measures (PM) are established and priorities are identified using a cause–effect assessment matrix and a global effectiveness index. Aiming to achieve more demanding goals, some complementary actions are considered, including “decentralized low-energy wastewater treatment plants construction”. A geographic information system was used to select potential implementation sites, and suitable treatment processes for each location are identified. The centralized and decentralized wastewater treatment plants combination is promising, achieving a cost-effectiveness attendance of €1510/equivalent-inhabitant in Minho–Lima river basins

    Oxidative precipitation synthesis of calcium-doped manganese ferrite nanoparticles for magnetic hyperthermia

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    Superparamagnetic nanoparticles are of high interest for therapeutic applications. In this work, nanoparticles of calcium-doped manganese ferrites (CaxMn1−xFe2O4) functionalized with citrate were synthesized through thermally assisted oxidative precipitation in aqueous media. The method provided well dispersed aqueous suspensions of nanoparticles through a one-pot synthesis, in which the temperature and Ca/Mn ratio were found to influence the particles microstructure and morphology. Consequently, changes were obtained in the optical and magnetic properties that were studied through UV-Vis absorption and SQUID, respectively. XRD and Raman spectroscopy studies were carried out to assess the microstructural changes associated with stoichiometry of the particles, and the stability in physiological pH was studied through DLS. The nanoparticles displayed high values of magnetization and heating efficiency for several alternating magnetic field conditions, compatible with biological applications. Hereby, the employed method provides a promising strategy for the development of particles with adequate properties for magnetic hyperthermia applications, such as drug delivery and cancer therapy.This work was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UIDB/04650/2020, UIDP/04650/2020), CQUM (UIDB/00686/2020), CICECO Aveiro Institute of Materials (UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020) and by Ministerio de Economía y Competitividad de España (PID2020-113704RB-I00 and PID2020-119242RB-I00), Xunta de Galicia (Centro Singular de Investigación de Galicia—Accreditation 2019-2022 ED431G 2019/06 and IN607A 2018/5 and project ED431C 2020-06), and European Union (EU-ERDF Interreg V-A—Spain-Portugal 0245_IBEROS_1_E, 0712_ACUINANO_1_E, and 0624_2IQBIONEURO_6_E, and Interreg Atlantic Area NANOCULTURE 1.102.531), and the European Union H2020-MSCA-RISE-2019 PEPSA-MATE project. S.R.S. (872233) Veloso acknowledges FCT for a PhD grant (SFRH/BD/144017/2019). Support from MAP-Fis Doctoral Programme is also acknowledged

    Magnetoliposomes incorporated in peptide-based hydrogels: towards development of magnetolipogels

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    A major problem with magnetogels is the encapsulation of hydrophobic drugs. Magnetoliposomes not only provide these domains but also improve drug stability and avert the aggregation of the magnetic nanoparticles. In this work, two magnetoliposome architectures, solid and aqueous, were combined with supramolecular peptide-based hydrogels, which are of biomedical interest owing to their biocompatibility, easy tunability, and wide array of applications. This proof-of-concept was carried out through combination of magnetoliposomes (loaded with the model drug curcumin and the lipid probe Nile Red) with the hydrogels prior to pH triggered gelation, and fluorescence spectroscopy was used to assess the dynamics of the encapsulated molecules. These systems allow for the encapsulation of a wider array of drugs. Further, the local environment of the encapsulated molecules after gelation is unaffected by the used magnetoliposome architecture. This system design is promising for future developments on drug delivery as it provides a means to independently modify the components and adapt and optimize the design according to the required conditions.FCT -Fundação para a Ciência e a Tecnologia(UIDB/00686/2020

    Impact of citrate and lipid-functionalized magnetic nanoparticles in dehydropeptide supramolecular magnetogels: properties, design and drug release

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    Currently, the nanoparticle functionalization effect on supramolecular peptide-based hydrogels remains undescribed, but is expected to affect the hydrogels' self-assembly and final magnetic gel properties. Herein, two different functionalized nanoparticles: citrate-stabilized (14.4 ± 2.6 nm) and lipid-coated (8.9 ± 2.1 nm) magnetic nanoparticles, were used for the formation of dehydropeptide-based supramolecular magnetogels consisting of the ultra-short hydrogelator Cbz-L-Met-Z-ΔPhe-OH, with an assessment of their effect over gel properties. The lipid-coated nanoparticles were distributed along the hydrogel fibers, while citrate-stabilized nanoparticles were aggregated upon gelation, which resulted into a heating efficiency improvement and decrease, respectively. Further, the lipid-coated nanoparticles did not affect drug encapsulation and displayed improved drug release reproducibility compared to citrate-stabilized nanoparticles, despite the latter attaining a stronger AMF-trigger. This report points out that adsorption of nanoparticles to hydrogel fibers, which display domains that improve or do not affect drug encapsulation, can be explored as a means to optimize the development of supramolecular magnetogels to advance theranostic applications.Ministerio de Economía y Competitividad (MINECO, Spain) under the Grant (CTM2017-84050-R), Xunta de Galicia/FEDER (IN607A 2018/5 and Centro Singular de Investigación de Galicia accreditation 2019-2022, ED431G 2019/06), 0712_ACUINANO_1_E, 0624_2IQBIONEURO_6_E and NANOCULTURE cofounded by FEDER through the program Interreg V-A España-Portugal (POCTEP), NANOCULTURE (ERDF: 1.102.531) Interreg Atlantic Area, the European Union (European Regional Development Fund-ERDF)

    Magnetogels: prospects and main challenges in biomedical applications

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    Drug delivery nanosystems have been thriving in recent years as a promising application in therapeutics, seeking to solve the lack of specificity of conventional chemotherapy targeting and add further features such as enhanced magnetic resonance imaging, biosensing and hyperthermia. The combination of magnetic nanoparticles and hydrogels introduces a new generation of nanosystems, the magnetogels, which combine the advantages of both nanomaterials, apart from showing interesting properties unobtainable when both systems are separated. The presence of magnetic nanoparticles allows the control and targeting of the nanosystem to a specific location by an externally applied magnetic field gradient. Moreover, the application of an alternating magnetic field (AMF) not only allows therapy through hyperthermia, but also enhances drug delivery and chemotherapeutic desired effects, which combined with the hydrogel specificity, confer a high therapeutic efficiency. Therefore, the present review summarizes the magnetogels properties and critically discusses their current and recent biomedical applications, apart from an outlook on future goals and perspectives.This work was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UID/FIS/04650/2013) and CQUM (UID/QUI/00686/2016). S.R.S.V. acknowledges FCT for a research grant under UID/FIS/04650/2013 funding.info:eu-repo/semantics/publishedVersio

    On the Dynamics of the Evolution of the HIV Infection

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    We use a cellular automata model to study the evolution of HIV infection and the onset of AIDS. The model takes into account the global features of the immune response to any pathogen, the fast mutation rate of the HIV and a fair amount of spatial localization. Our results reproduce quite well the three-phase pattern observed in T cell and virus counts of infected patients, namely, the primary response, the clinical latency period and the onset of AIDS. We have also found that the infected cells may organize themselves into special spatial structures since the primary infection, leading to a decrease on the concentration of uninfected cells. Our results suggest that these cell aggregations, which can be associated to syncytia, leads to AIDS.Comment: 4 pages, 3 postscript figure

    Marine biotechnology in Brazil : recent developments and its potential for innovation

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    Marine biotechnology is an emerging field in Brazil and includes the exploration of marine microbial products, aquaculture, omics, isolation of biologically active compounds, identification of biosynthetic gene clusters from symbiotic microorganisms, investigation of invertebrate diseases caused by potentially pathogenic marine microbes, and development of antifouling compounds. Furthermore, the field also encompasses description of new biological niches, current threats, preservation strategies as well as its biotechnological potential. Finally, it is important to depict some of the major approaches and tools being employed to such end. To address the challenges of marine biotechnology, the Brazilian government, through the Ministry of Science, Technology, Innovation, and Communication, has established the National Research Network in Marine Biotechnology (BiotecMar) (www.biotecmar.sage.coppe.ufrj.br). Its main objective is to harness marine biodiversity and develop the marine bioeconomy through innovative research
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