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- Indoor air quality in a home improvement store: Gaseous pollutants, bioburden and particle-bound chemical constituentsPublication . Furst, Leonardo; Cipoli, Yago; Yubero, Eduardo; Galindo, Nuria; Viegas, Carla; Dias, Marta; Nunes, Teresa; Igrejas, GetĂșlio; Feliciano, Manuel; CĂ©lia AlvesThis paper provides a comprehensive assessment of indoor and outdoor air quality within a home improvement and gardening store chain in northeastern Portugal. In December 2021 and January 2022, two multipollutant systems were installed in the store and outdoors to assess air quality. Continuous monitoring included particulate matter below 10 ÎŒm (PM10), CO2 and comfort parameters. PM10 samples were collected using gravimetric samplers during both occupied and vacant periods. These samples were then analysed for carbonaceous con- stituents and metal(loid)s. Additionally, volatile organic compounds (VOCs), carbonyls, bacteria, and fungi were passively sampled. Results showed higher indoor concentrations of PM10 during labour hours (45.4 ± 15.2 ÎŒg/ m3), while outdoor values of 27.1 ± 9.96 ÎŒg/m3 were recorded. The elemental characterisation of PM10 revealed a high abundance of soil-related elements indoors, suggesting that resuspension is one of the primary sources. The most abundant elements were Ca, Fe, and Zn, with concentrations of 658 ± 297, 273 ± 141, and 172 ± 67.4 ng/mÂł, respectively. Outdoors, elements related to tyre and brake wear and road dust were predominant, indicating emissions from non-exhaust traffic emissions as the main source. A prevalence of α-pinene, limonene, and hexanal was found indoors, most likely related to wood products. Fungi with clinical relevance and toxigenic potential, and higher bacterial loads were observed in the gardening and heating sectors of the store. This study underscores the importance of investigating less-studied stores, as they may exhibit pollutant levels that exceed health protection thresholds
- Manual de boas prĂĄticas de segurança e saĂșde no trabalho apĂcola uma abordagem para uma cultura de segurança no setorPublication . Pires, SĂąncia; Martins, Vitor Manuel Ramalheira; Igrejas, GetĂșlio; Coelho, JoĂŁo Paulo; Machado, Ana; Pereira, Ana Paula; Nunes, SofiaA qualidade das condiçÔes de trabalho Ă© um dos fatores fundamentais para o sucesso de um sistema produtivo e, o mesmo, tambĂ©m se aplica ao setor apĂcola. Nesse Ăąmbito, a melhoria da produtividade e da competitividade depende, necessariamente, de uma intervenção no sentido da perceção e melhoria das condiçÔes de trabalho. Neste contexto, a elaboração de um Manual de Boas PrĂĄticas de Segurança e SaĂșde no trabalho apĂcola pretende dar continuidade ao incremento e transferĂȘncia de conhecimentos tĂ©cnicos aos apicultores e a todos os agentes envolvidos nesta atividade, contribuindo para uma melhor estruturação do setor. Tendo em consideração a reduzida quantidade de literatura que se encontra disponĂvel, incluindo manuais e outros documentos referentes a Boas PrĂĄticas de Segurança e SaĂșde no trabalho apĂcola, considera-se que a elaboração de um manual, nĂŁo vinculativo e de carĂĄter orientador, poderĂĄ trazer um contributo relevante e pertinente para a atividade.
- Metodologia para anĂĄlisis inteligente de energĂa y calidad de aire en viviendas y espacios exteriores. AdaptaciĂłn y monitorizaciĂłn de instalaciones: relatĂłrio do Projeto POCTEP 0640_ENER_USER_2_EPublication . Gonçalves, Artur; Igrejas, GetĂșlio; Frigeri, Ary Vinicius; Feliciano, Manuel; Vaz, AntĂłnio Jorge Ferreira; Soares, Orlando; Alves, Paulo; Castaño PĂ©rez, ValentĂn; DomĂnguez Carrrero, JosĂ© Ignacio; SĂĄnchez GarcĂa, Luis MÂȘ; Romero SalvachĂșa, Felipe; RodrĂguez OraĂĄ, BĂĄrbara; Vielba GarcĂa, JosĂ© Javier
- Manual de boas prĂĄticas de higiene, segurança e saĂșde no trabalho apĂcola: beekeeper safety - Abordagem para uma cultura de segurança no sectorPublication . Pires, Sancia; Martins, Vitor Manuel Ramalheira; Igrejas, GetĂșlio; Coelho, JoĂŁo Paulo; Pereira, Ana Paula; Ferreira, Adriano; SĂĄ, DianaA higiene, segurança e saĂșde no trabalho diz respeito a diversas e diferentes medidas que precisam ser adotadas numa organização com o intuito de prevenir acidentes e doenças profissionais e reduzir os riscos ocupacionais para os trabalhadores. Assim, a garantia de segurança e saĂșde nos locais de trabalho Ă© um direito de todos os trabalhadores que deve ser assegurado pelo empregador, tendo em conta os princĂpios gerais de prevenção referidos no artigo 15Âș da Lei nÂș 102/2009, de 10 de setembro, alterada pela Lei nÂș 3/2014, de 28 de janeiro.
- A portable device for methane measurement using a low-cost semiconductor sensor: development, calibration and environmental applicationsPublication . Furst, Leonardo; Feliciano, Manuel; Frare, Laercio; Igrejas, GetĂșlioMethane is a major greenhouse gas and a precursor of tropospheric ozone, and most of its sources are linked to anthropogenic activities. The sources of methane are well known and its monitoring generally involves the use of expensive gas analyzers with high operating costs. Many studies have investigated the use of low-cost gas sensors as an alternative for measuring methane concentrations; however, it is still an area that needs further development to ensure reliable measurements. In this work a low-cost platform for measuring methane within a low concentration range was developed and used in two distinct environments to continuously assess and improve its performance. The methane sensor was the Figaro TGS2600, a metal oxide semiconductor (MOS) based on tin dioxide (SnO2). In a first stage, the monitoring platform was applied in a small ruminant barn after undergoing a multi-point calibration. In a second stage, the system was used in a wastewater treatment plant together with a multi-gas analyzer (Gasera One Pulse). The calibration of low-cost sensor was based on the relation of the readings of the two devices. Temperature and relative humidity were also measured to perform corrections to minimize the effects of these variables on the sensor signal and an active ventilation system was used to improve the performance of the sensor. The system proved to be able to measure low methane concentrations following reliable spatial and temporal patterns in both places. A very similar behavior between both measuring systems was also well noticeable at WWTP. In general, the low-cost system presented good performance under several environmental conditions, showing itself to be a good alternative, at least as a screening monitoring system.
- Fall detection system for elderly people : a neural network approachPublication . Igrejas, GetĂșlio; Amaral, Joana S.; Rodrigues, Pedro JoĂŁoIn this work a new approach for a fall detection system is proposed. The device integrates a 3-axis accelerometer and a 3-axis gyroscope to measure linear acceleration and angular velocities, respectively. Information from both sensors is used to characterize movements through selected features extracted from raw data. A classification system based on a Feedforward Backpropagation Neural Network is then trained, based on the extracted features. The performed tests present low false positives and low false negatives rates with good specificity and sensitivity values.
- Differentiation of production method and geographical origin of salmon based on the analysis of fatty acid compositionPublication . Amaral, Joana S.; Grazina, Liliana; Nunes, Maria; Mafra, Isabel; Rodrigues, Pedro JoĂŁo; Igrejas, GetĂșlio; Oliveira, BeatrizCurrently, aquaculture production supplies almost 50% of the global fish market, as a response to the increasing global demand for fish [1]. However, several consumers prefer wild over farmed fish, with the former generally attaining higher prices when the some species is considered. Therefore, there is the need to assure correct information, not only about the species, but also about the production method (farmed vs. wild) and the catch origin of fish. Salmon, a high-trophic - level carnivorous species with high economic value due to its popularity, is among the fish species that is frequently produced in aquoculture. Although the feed given to farm-raised salmon is designed to meet its nutritional requirements, it can present differences compared to the diet of wild salmon that con be reflected on the muscle composition of formed versus wild solmons. Therefore, in this work, the use of fatty acid composition combined with chemometrics was evaluated as a potential tool to authenticate salmon samples. In particular, the work aimed at identifying the geographical origin and production method (farmed vs. caught in the wild) of salmon.
- Fall detection systems to be used by elderly peoplePublication . Igrejas, GetĂșlio; Amaral, Joana S.; Rodrigues, Pedro JoĂŁoStatistics show that, each year, falls affect tens of millions of elderly people throughout the world. Falls are the leading cause of injury deaths and injury-related hospitalization among people over 65 years old. A system able to automatically detect falls could be an important tool from a social point of view, as it would contribute to the prompt assistance of these emergency cases. Currently, many researchers are interested in the development of fall detection systems. This chapter presents several approaches suggested so far, with special attention to the different strategies and technologies applied. Other sen- sor technologies that could be applied to this field are also referred. Additionally, a new fall detection system based on a machine learning paradigm, using neural networks, is suggested. The system was trained using fall and non-fall examples. Although the test set has included some particular examples, problematic for detection of the correspondent motion, the obtained results present good specificity (88.9%) and sensitivity (93.9%) rates.
- Chemical characterization and antimicrobial activity of ozonized oil against methicillin resistant Staphylococcus aureusPublication . Silva, Vanessa; Peirone, CecĂlia; Amaral, Joana S.; Marques-Magallanes, JosĂ© A.; Igrejas, GetĂșlio; Poeta, PatrĂciaMethicillin resistant Staphylococcus aureus (MRSA) are frequently found in infected skin wounds due to the exposure of deep tissues to the bacteria, in particular in infected diabetic foot ulcers in which the prevalence can be between 15 to 40% [1]. Clinical MRSA are usually resistant to most classes of antibiotics and, therefore, it is necessary to investigate new antimicrobial agents. Ozone has a recognized bactericidal activity and has been widely used as a clinical therapeutic agent for chronic wounds, such as, ulcers and other diabetic lesions, due to its wound healing ability [2]. This study aimed to characterize ozone oil suspensions and their activity against MRSA isolated from infected diabetic foot ulcers. Six ozonized oils with different ozonization doses were tested by disk diffusion method. The oils were prepared from a 50:50 mixture of extra virgin olive oil and refined sunflower oil and submitted to a gas stream of O2/O3 mixture at a concentration of 75 ÎŒg/ml of ozone in continuous flow (4 L/min). The oil content in fatty acid methyl esters after ozonization were investigated using a BrukerÂź SCION 436-GC gas chromatograph equipped with a flame ionization detector (GC-FID). All ozone suspension oils tested showed antimicrobial activity against all strains. The ozone suspension oil with the highest ozonization dose originated clear zones with a maximum of 12 mm. Composition of fatty acids in ozonized oils showed gradual decrease in unsaturated fatty acids with gradual increase in ozone doses. Overall, there was a decrease in the total fatty acid investigated and an increase in the content of unknown oxidized fatty acid with the increase of ozonization period. Our results indicate that ozonized oils have a significant antimicrobial activity, however, it is still unclear which compounds may be responsible for the bactericidal action.
- A neural network based fall detectorPublication . Rodrigues, Pedro JoĂŁo; Amaral, J.S.; Igrejas, GetĂșlioIn this project we present an intelligent fall detector system based on a 3-axis accelerometer and a neural network model that allows recognizing severaI possible motion situations and performing an emergency call only when a fall situation occurs, with low false negatives rate and low false positives rate. The system is based on a two module platform. The first one is a Mobile station (MS) and should be carried always by the person. An accelerometer is implemented in this module and its information is transferred via a radio-frequency channel (RF) to the Base station (BS). The BS is fixed and is connected to a GSM (Global system for Mobile communication) module. A neural network model was built in to the BS and is able to identify falls from other possible motion situations, based on the received information. According to the neural network response the system sends a SMs (short Message service) to a destination number requesting for assistance.