Low-cost upconversion nanomaterials for anti-counterfeiting solutions

This work consisted on the production and characterization of low-cost upconversion (UC) nanoparticles based on zirconia oxides (ZrO2). The production was made by a hydrothermal process assisted by microwave irradiation, where 4 reagents were tested: sodium hydroxide, hexamethylenetetramine, urea and ethylenediamine. Ytterbium (Yb) and erbium (Er) were used as dopants to allow the upconversion process. The aim was that the nanoparticles would match photoluminescent characteristics of a detector provided by INCM (Imprensa Nacional – Casa da Moeda) so that it can be used as a security marker. Hexamethylenetetramine has proven to be the best reagent to reach the desired nanoparticles with a maximum size of 100 nm. It was concluded that no dispersant was necessary to stabilize the powder when added directly into the proper ink. Different synthesis parameters were tested to optimize the morphology and size of nanomaterials such as time, pH and temperature. It was also achieved the scale up production of this nanoparticles, since passing from 25 ml to 600 ml solutions did not alter the optical response. Both flexographic and screen printing were proven successful printing methods as the final luminescent outcome matched the marker characteristics. A cheaper, environmentally friendly and new marker was accomplished, allowing that more products may have a security mark, guaranteeing their final authenticity

Influence of different copper materials on biofilm control using chlorine and mechanical stress

The selection of materials for plumbing application has potential implications on the chemical and microbiological quality of the delivered water. This work aims to evaluate the action of materials with different copper content (0, 57, 96 and 100%) on biofilm formation and control by chlorination and mechanical stress. A strain of Stenotrophomonas maltophilia isolated from drinking water was used as model microorganism and biofilms were developed in a rotating cylinder reactor (RCR) using realism-based shear stress conditions. Biofilms were characterized phenotypically and exposed to three control strategies: 10 mg/l of free chlorine for 10 min; an increased shear stress (equivalent to 1.5 m/s of fluid velocity); and the combination of both treatments. Biofilms formed on the copper materials had lower wet mass and produced significantly lower amounts of extracellular proteins than those formed on stainless steel (0% of copper content). Although, the effects of copper materials on biofilm cell density was not significant, these materials had important impact on the efficacy of chemical and/or mechanical treatments. Biofilms formed on 96 or 100% copper materials had lower content of culturable bacteria than that observed on stainless steel after exposure to chlorine or shear stress. The mechanical treatment used had no relevant effects in biofilm control. The combination of chemical and mechanical treatments only caused higher culturability reduction than chlorine in biofilms formed on 57% copper alloy. The number of viable cells present in bulk water after biofilm treatment with chlorine was lower when biofilms were formed on any of the copper surface. The overall results are of potential importance on the selection of materials for drinking water distribution systems, particularly for house and hospital plumbing systems to overcome the effects from chlorine decay. Copper alloys may have a positive public health impact by reducing the number of viable cells in the delivered water after chlorine exposure and improving the disinfection of DW systems. Moreover, the results demonstrate that residual chlorine and mechanical stress, two strategies conventionally used for disinfection of drinking water distribution systems, failed in S. maltophilia biofilm control.This work was the result of the projects: UIDB/00511/2020 of the Laboratory for ProcessEngineering, Environment, Biotechnology and Energy – LEPABE - funded by national funds throughthe FCT/MCTES(PIDDAC); PTDC/BII-BTI/30219/2017-POCI-01-0145-FEDER-030219;POCI-01-0145-FEDER-006939, funded by FEDER funds through COMPETE2020 – ProgramaOperacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) throughFCT/MCTES; NORTE-01-0145-FEDER-000005 – LEPABE-2-ECO-INNOVATION, supported by NortePortugal Regional Operational Programme (NORTE 2020), under PORTUGAL 2020 PartnershipAgreement, through the European Regional Development Fund (ERDF)info:eu-repo/semantics/publishedVersio

Legionella pneumophila

Legionella pneumophila is an intracellular pathogen, ubiquitous in the environment and considered opportunistic. It is the leading cause of legionellosis, which can be present in its nonpneumonic form (Pontiac fever) and acute pneumonic form (Legionnaires` disease – LD). In the soil and aquatic systems, L. pneumophila can invade and survive intracellularly in various protozoans. The ability to proliferate within biofilms provides additional protection from environmental stresses, such as disinfection. Human infection by L. pneumophila occurs after the inhalation or aspiration of aerosols containing the pathogen. Upon infection, alveolar macrophages can be invaded and used by L. pneumophila for replication, resembling the infection of protozoan hosts in the environment. The ability of L. pneumophila to overcome the killing mechanisms of phagocytes depends on the Dot/Icm type IV secretion system – a specialized protein translocation system vital for the intracellular survival of the pathogen and for establishing a replicative niche known as the Legionella-containing vacuole. Following host cell lysis, the released bacteria infect other host cells, beginning a new cycle of infection.This work was financially supported by Base Funding – UIDB/00511/2020 of LEPABE and funded by national funds through the FCT/MCTES (PIDDAC); Project Biocide_for_Biofilm – PTDC/BII-BTI/30219/2017 – POCI-01-0145-FEDER-030219, pBio4.0 – POCI-01-0247-FEDER-033298, funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE 01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Copper surfaces in biofilm control

Biofilms are structures comprising microorganisms associated to surfaces and enclosed by an extracellular polymeric matrix produced by the colonizer cells. These structures protect microorganisms from adverse environmental conditions. Biofilms are typically associated with several negative impacts for health and industries and no effective strategy for their complete control/eradication has been identified so far. The antimicrobial properties of copper are well recognized among the scientific community, which increased their interest for the use of these materials in different applications. In this review the use of different copper materials (copper, copper alloys, nanoparticles and copper-based coatings) in medical settings, industrial equipment and plumbing systems will be discussed considering their potential to prevent and control biofilm formation. Particular attention is given to the mode of action of copper materials. The putative impact of copper materials in the health and/or products quality is reviewed taking into account their main use and the possible effects on the spread of antimicrobial resistance.This work was financially supported by: Base Funding—UIDB/00511/2020 of LEPABE and UIDB/00081/2020 of CIQUP funded by national funds through the FCT/MCTES (PIDDAC); Project Biocide_for_Biofilm—PTDC/BII-BTI/30219/2017—POCI-01-0145-FEDER-030219, ABFISH—PTDC/ASP-PES/28397/2017—POCI-01-0145-FEDER-028397 and ALGAVALOR—POCI-01-0247-FEDER-035234, funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte; SFRH/BSAB/150379/2019 (Manuel Simões).info:eu-repo/semantics/publishedVersio

The effects of different biocides against selected drinking water-isolated bacteria in planktonic and sessile states

The chemical disinfectant chlorine, as chlorine gas (Cl2) and sodium hypochlorite (NaOCl), has been commonly used for drinking water treatment.1,2 Although the recommended residual concentration of free chlorine allows to some extent the control of microbial growth in the bulk water, the occurrence of biofilms in chlorinated drinking water distribution systems (DWDS) has been frequently reported.3,4 Therefore, the main goal of this study was the study of alternative biocides to control biofilm development in DWDS. The effects of sodium dichloroisocyanurate (NaDCC), trichloroisocyanuric acid (TCCA), and pentapotassium bis(peroxymonosulphate) bis(sulphate) (OXONE®) were analysed against two emerging pathogens isolated from drinking water, Acinetobacter calcoaceticus and Stenotrophomonas maltophilia. The determination of the minimum bactericidal concentrations (MBC) of the selected biocides were based on the European Standard EN 1276, with MBC between 1.56 to 6.25 mg/L for NaDCC, 2.5 to 3.75 mg/L for TCCA, and 172 to 688 mg/L for OXONE®. Inactivation curves were developed and fitted to microbial survival models. The effects of biocides on cytoplasmic membrane integrity were assessed by propidium iodide uptake. The action on biofilm control was analysed against 48 h old biofilms developed on polyvinyl chloride (PVC) and stainless steel (SS) coupons using a 24-wells microtiter plate assay. The bacteria culturability and removal assessment were determined by colony forming units (CFU) enumeration on R2A agar, and by 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. This study reinforces biofilms as chronic contaminants of DWDS and highlights that the understanding of antimicrobial susceptibility of microorganisms to biocides is an important step in the design of effective biofilm control strategies in order to provide to consumers drinking water of adequate microbiological quality.This work was financially supported by: Base Funding - UIDB/00511/2020 of the Laboratory forProcess Engineering, Environment, Biotechnology and Energy – LEPABE - funded by national fundsthrough the FCT/MCTES (PIDDAC); PTDC/BII-BTI/30219/2017 - POCI-01-0145-FEDER-030219;POCI-01-0145-FEDER-006939, funded by FEDER funds through COMPETE2020 – ProgramaOperacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; and PhD grant awarded to Isabel Maria Oliveira (SFRH/BD/138117/2018).info:eu-repo/semantics/publishedVersio

Overview on the hydrodynamic conditions found in industrial systems and its impact in (bio)fouling formation

Supplementary data to this article can be found online at https://doi.org/10.1016/j.cej.2021.129348.Biofouling is the unwanted accumulation of deposits on surfaces, composed by organic and inorganic particles and (micro)organisms. Its occurrence in industrial equipment is responsible for several drawbacks related to operation and maintenance costs, reduction of process safety and product quality, and putative outbreaks of pathogens. The understanding on the role of operating conditions in biofouling development highlights the hydrodynamic conditions as key parameter. In general, (bio)fouling occurs in a higher extension when laminar flow conditions are used. However, the characteristics and resilience of biofouling are highly dependent on the hydrodynamic conditions under which it is developed, with turbulent conditions being associated to recalcitrant biodeposits. In industrial settings like heat exchangers, fluid distribution networks and stirred tanks, hydrodynamics play a dual function, affecting the process effectiveness while favouring biofouling formation. This review summarizes the hydrodynamics played in conventional industrial settings and provides an overview on the relevance of hydrodynamic conditions in biofouling development as well as in the effectiveness of industrial processes.This work was financially supported by: Base Funding - UIDB/00511/2020 of LEPABE and UIDB/00081/2020 of CIQUP funded by national funds through the FCT/MCTES (PIDDAC); Project Bio cide_for_Biofilm - PTDC/BII-BTI/30219/2017 - POCI-01-0145-FEDER 030219, ABFISH – PTDC/ASP-PES/28397/2017 - POCI-01-0145- FEDER-028397 and ALGAVALOR - POCI-01-0247-FEDER-035234, fun ded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalizaçao ˜ (POCI) and by national funds (PIDDAC) through FCT/MCTES; Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER 000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte; FCT/ SFRH/BD/147276/2019 (Susana Fernandes) and SFRH/BSAB/150379/2019 (Manuel Simoes).info:eu-repo/semantics/publishedVersio

Avaliação do contributo dos médicos dentistas na cessação tabágica e seu impacto nos procedimentos médico-dentários em clínicas de Braga (Freguesia de S.Lázaro)

Com o estudo em questão pretende-se avaliar que tipo de abordagem é realizada pelos Médicos Dentistas na freguesia de S. Lázaro – Braga e se estes manifestam preparação adequada após a conclusão do percurso académico para auxiliarem os seus pacientes em relação à cessação tabágica. Foi efetuado um estudo transversal, descritivo e quantitativo, para o qual se utilizou um questionário com 22 questões de resposta fechada, resposta fechada e aberta. Da recolha dos mesmos resultou uma amostra de 19 questionários válidos. Da análise dos resultados, verifica-se que o Médico Dentista não realiza consulta de cessação tabágica (78,95%), identificando a falta de tempo (10,53%) e a falta de competências (36,84%) como as principais razões para o facto. A maioria dos intervenientes refere que faz aconselhamento, um aconselhamento genérico está presente em 42,11% dos inquiridos, 5.26% enviam para consulta de cessação tabágica, e nenhum dos inquiridos refere aplicar um programa de cessação tabágica. A grande maioria não referenciou mais do que 5 utentes para consultas com esta finalidade. De salientar, que a maior parte (73.68%) dos inquiridos referem não possuir formação académica adequada para prestarem ajuda aos seus pacientes fumadores. Como principais conclusões deste estudo, destaca-se o interesse em participar em ações de formação por parte dos inquiridos, de forma a complementarem a sua formação académica e desenvolverem competências clínicas para darem resposta mais eficaz na abordagem do processo de desabituação tabágica.This study aims to assess the type of approach performed by dentists in the parish of S. Lázaro – Braga, and whether they show adequate preparation after concluding their academic degree to assist their patients in terms of smoking cessation. A cross-sectional, descriptive and quantitative study was carried out, using a questionnaire with 22 questions of closed response, closed and open response. The data collection allowed obtaining a sample of 19 valid questionnaires. The analysis of the results reveals that the dentist does not perform smoking cessation consultation (78.95%), identifying lack of time (10.53%) and lack of competencies (36.84%) as the main reasons for this. The majority of respondents reported that they provide counselling, general counselling is present in 42,11% of respondents, 5.26% channel for smoking cessation consultation, and no one applies a smoking cessation program. The majority of respondents refer until 5 patients for consultations with this purpose. To note that the majority (73.68%) of the respondents state that they do not have adequate academic training to help their smoker patients. The main conclusion of this study is the interest in participating in training actions by the respondents, in order to complement their academic training and develop clinical skills to respond more effectively in the approach to smoking cessation process

Avaliação do contributo dos médicos dentistas na cessação tabágica e seu impacto nos procedimentos médico-dentários em clínicas de Braga (Freguesia de S.Lázaro)

Com o estudo em questão pretende-se avaliar que tipo de abordagem é realizada pelos Médicos Dentistas na freguesia de S. Lázaro – Braga e se estes manifestam preparação adequada após a conclusão do percurso académico para auxiliarem os seus pacientes em relação à cessação tabágica. Foi efetuado um estudo transversal, descritivo e quantitativo, para o qual se utilizou um questionário com 22 questões de resposta fechada, resposta fechada e aberta. Da recolha dos mesmos resultou uma amostra de 19 questionários válidos. Da análise dos resultados, verifica-se que o Médico Dentista não realiza consulta de cessação tabágica (78,95%), identificando a falta de tempo (10,53%) e a falta de competências (36,84%) como as principais razões para o facto. A maioria dos intervenientes refere que faz aconselhamento, um aconselhamento genérico está presente em 42,11% dos inquiridos, 5.26% enviam para consulta de cessação tabágica, e nenhum dos inquiridos refere aplicar um programa de cessação tabágica. A grande maioria não referenciou mais do que 5 utentes para consultas com esta finalidade. De salientar, que a maior parte (73.68%) dos inquiridos referem não possuir formação académica adequada para prestarem ajuda aos seus pacientes fumadores. Como principais conclusões deste estudo, destaca-se o interesse em participar em ações de formação por parte dos inquiridos, de forma a complementarem a sua formação académica e desenvolverem competências clínicas para darem resposta mais eficaz na abordagem do processo de desabituação tabágica.This study aims to assess the type of approach performed by dentists in the parish of S. Lázaro – Braga, and whether they show adequate preparation after concluding their academic degree to assist their patients in terms of smoking cessation. A cross-sectional, descriptive and quantitative study was carried out, using a questionnaire with 22 questions of closed response, closed and open response. The data collection allowed obtaining a sample of 19 valid questionnaires. The analysis of the results reveals that the dentist does not perform smoking cessation consultation (78.95%), identifying lack of time (10.53%) and lack of competencies (36.84%) as the main reasons for this. The majority of respondents reported that they provide counselling, general counselling is present in 42,11% of respondents, 5.26% channel for smoking cessation consultation, and no one applies a smoking cessation program. The majority of respondents refer until 5 patients for consultations with this purpose. To note that the majority (73.68%) of the respondents state that they do not have adequate academic training to help their smoker patients. The main conclusion of this study is the interest in participating in training actions by the respondents, in order to complement their academic training and develop clinical skills to respond more effectively in the approach to smoking cessation process

Biofilm control by ionic liquids

Ionic liquids (ILs) are remarkable chemical compounds with applications in many areas of modern science. They are increasingly recognized as promising compounds to fight microorganisms in both planktonic and biofilm states, contributing to reinvent the antimicrobial pipeline. Biofilm-related infections are particularly challenging given that the scientific community has not yet identified a reliable control strategy. Understanding of the action of ILs in biofilm control is lacking. However, given the highly tunable nature and exceptional properties of ILs, they are excellent candidates for biofilm control. Here, we review the major advances in, and challenges to, the use of ILs for effective biofilm control.Base Funding - UIDB/00511/2020 of LEPABE, UIDB/00081/2020 of CIQUP, and UIDB/04469/2020 of CEB funded by national funds through the FCT/MCTES (PIDDAC); Project Biocide_for_Biofilm - PTDC/BII-BTI/30219/2017 - POCI-01-0145-FEDER-030219, ABFISH – PTDC/ASP-PES/28397/2017 - POCI-01-0145-FEDER-028397, funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES, and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norteinfo:eu-repo/semantics/publishedVersio

The effects of chemical and mechanical stresses on Bacillus cereus and Pseudomonas fluorescens single- and dual-species biofilm removal

Biofilm control is mainly based on chemical disinfection, without a clear understanding of the role of the biocides and process conditions on biofilm removal. This study aims to understand the effects of a biocide (benzyldimethyldodecyl ammonium chlorideBDMDAC) and mechanical treatment (an increase of shear stress -w) on single- and dual-species biofilms formed by Bacillus cereus and Pseudomonas fluorescens on high-density polyethene (HDPE). BDMDAC effects were initially assessed on bacterial physicochemical properties and initial adhesion ability. Then, mature biofilms were formed on a rotating cylinder reactor (RCR) for 7 days to assess the effects of chemical and mechanical treatments, and the combination of both on biofilm removal. The results demonstrated that the initial adhesion does not predict the formation of mature biofilms. It was observed that the dual-species biofilms were the most susceptible to BDMDAC exposure. The exposure to increasing w emphasised the mechanical stability of biofilms, as lower values of w (1.66 Pa) caused high biofilm erosion and higher w values (17.7 Pa) seem to compress the remaining biofilm. In general, the combination of BDMDAC and the mechanical treatment was synergic in increasing biofilm removal. However, these were insufficient to cause total biofilm removal (100%; an average standard deviation of 11% for the method accuracy should be considered) from HDPE.This work was financially supported by: Base Funding—UIDB/00511/2020 of LEP-ABE funded by national funds through the FCT/MCTES (PIDDAC); Project Biocide_for_Biofilm—TDC/BII-BTI/30219/2017—POCI-01-0145-FEDER-030219; Germirrad—POCI-01-0247-FEDER-072237; pBio4.0—POCI-01-0247-FEDER-033298, funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES. This study was further supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio