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The comet assay is a versatile method to detect nuclear DNA damage in individual eukaryotic cells, from yeast to human. The types of damage detected encompass DNA strand breaks and alkali-labile sites (e.g., apurinic/apyrimidinic sites), alkylated and oxidized nucleobases, DNA-DNA crosslinks, UV-induced cyclobutane pyrimidine dimers and some chemically induced DNA adducts. Depending on the specimen type, there are important modifications to the comet assay protocol to avoid the formation of additional DNA damage during the processing of samples and to ensure sufficient sensitivity to detect differences in damage levels between sample groups. Various applications of the comet assay have been validated by research groups in academia, industry and regulatory agencies, and its strengths are highlighted by the adoption of the comet assay as an in vivo test for genotoxicity in animal organs by the Organisation for Economic Co-operation and Development. The present document includes a series of consensus protocols that describe the application of the comet assay to a wide variety of cell types, species and types of DNA damage, thereby demonstrating its versatility.The comet assay is commonly used to assess DNA damage. This collection of consensus protocols includes adaptations for a wide range of species and sample types, assay formats and detection of different types of DNA lesions.

Measurement of DNA migration in the comet assay can be done by image analysis or visual scoring. The latter accounts for 20-25% of the published comet assay results. Here we assess the intra- and inter-investigator variability in visual scoring of comets. We include three training sets of comet images, which can be used as reference for researchers who wish to use visual scoring of comets. Investigators in 11 different laboratories scored the comet images using a five-class scoring system. There is inter-investigator variation in the three training sets of comets (i.e. coefficient of variation (CV) = 9.7%, 19.8% and 15.2% in training sets I-III, respectively). However, there is also a positive correlation of inter-investigator scoring in the three training sets (r = 0.60). Overall, 36% of the variation is attributed to inter-investigator variation and 64% stems from intra-investigator variation in scoring between comets (i.e. the comets in training sets I-III look slightly different and this gives rise to heterogeneity in scoring). Intra-investigator variation in scoring was also assessed by repeated analysis of the training sets by the same investigator. There was larger variation when the training sets were scored over a period of six months (CV = 5.9-9.6%) as compared to one week (CV = 1.3-6.1%). A subsequent study revealed a high inter-investigator variation when premade slides, prepared in a central laboratory, were stained and scored by investigators in different laboratories (CV = 105% and 18-20% in premade slides with comets from unexposed and hydrogen peroxide-exposed cells, respectively). The results indicate that further standardization of visual scoring is desirable. Nevertheless, the analysis demonstrates that visual scoring is a reliable way of analysing DNA migration in comets.

The comet assay is a simple and versatile method for measurement of DNA damage in eukaryotic cells. More specifically, the assay detects DNA migration from agarose gel-embedded nucleoids, which depends on assay conditions and the level of DNA damage. Certain steps in the comet assay procedure have substantial impact on the magnitude of DNA migration (e.g. electric potential and time of electrophoresis). Inter-laboratory variation in DNA migration levels occurs because there is no agreement on optimal assay conditions or suitable assay controls. The purpose of the hCOMET ring trial was to test potassium bromate (KBrO3) as a positive control for the formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay. To this end, participating laboratories used semi-standardized protocols for cell culture (i.e. cell culture, KBrO3 exposure, and cryopreservation of cells) and comet assay procedures, whereas the data acquisition was not standardized (i.e. staining of comets and image analysis). Segregation of the total variation into partial standard deviation (SD) indicates importance of cell culture procedures (SD = 10.9), comet assay procedures (SD = 12.3), staining (SD = 7.9) and image analysis (SD = 0.5) on the overall inter-laboratory variation of DNA migration (SD = 18.2). Future studies should assess sources of variation in each of these steps. On the positive side, the hCOMET ring trial demonstrates that KBrO3 is a robust positive control for the Fpg-modified comet assay. In conclusion, the hCOMET ring trial has demonstrated a high reproducibility of detecting genotoxic effects by the comet assay, but inter-laboratory variation of DNA migration levels is a concern.

[Abstract] Introduction: Immunosenescence and inflammaging have been implicated in the pathophysiology of frailty. Torquetenovirus (TTV), a single-stranded DNA anellovirus, the major component of the human blood virome, shows an increased replication rate with advancing age. An elevated TTV viremia has been associated with an impaired immune function and an increased risk of mortality in the older population. The objective of this study was to analyze the relation between TTV viremia, physical frailty, and cognitive impairment. Methods: TTV viremia was measured in 1,131 nonfrail, 45 physically frail, and 113 cognitively impaired older adults recruited in the MARK-AGE study (overall mean age 64.7 ± 5.9 years), and then the results were checked in two other independent cohorts from Spain and Portugal, including 126 frail, 252 prefrail, and 141 nonfrail individuals (overall mean age: 77.5 ± 8.3 years). Results: TTV viremia ≥4log was associated with physical frailty (OR: 4.69; 95% CI: 2.06-10.67, p < 0.0001) and cognitive impairment (OR: 3.49, 95% CI: 2.14-5.69, p < 0.0001) in the MARK-AGE population. The association between TTV DNA load and frailty status was confirmed in the Spanish cohort, while a slight association with cognitive impairment was observed (OR: 1.33; 95% CI: 1.000-1.773), only in the unadjusted model. No association between TTV load and frailty or cognitive impairment was found in the Portuguese sample, although a negative association between TTV viremia and MMSE score was observed in Spanish and Portuguese females. Conclusions: These findings demonstrate an association between TTV viremia and physical frailty, while the association with cognitive impairment was observed only in the younger population from the MARK-AGE study. Further research is necessary to clarify TTV's clinical relevance in the onset and progression of frailty and cognitive decline in older individuals. Ministerio de Ciencia e Innovación (España); PID2020-113788RB-I00 Xunta de Galicia; ED431B 2022/16 Xunta de Galicia; ED431F 2017/09

Nesta pesquisa se apresenta os resultados de um estudo que buscou investigar as contribuições da escrita do diário de campo na formação de um grupo de 7 licenciandos em química, produzidos no Estágio Curricular Supervisionado (ECS) 1 e 2. Em consonância, esta pesquisa figura como um estudo de caso. Foram analisados ao todo 76 diários de campo por meio das categorias de Zabalza (2009) e outras emergentes, adotando-se a análise de conteúdo. Nos resultados identificou-se que a maioria dos licenciandos compartilharam nos diários produzidos no ECS 1 a descrição de tarefas, enquanto no ECS 2 os diários emergiram, principalmente, as características dos alunos e dos próprios professores. Em relação às categorias emergentes, as mais significativas foram as que trouxeram características dos estudantes da educação básica e a caracterização das aulas do professor supervisor, incipientes, foram o olhar dos licenciandos para a escola, situações conflitantes e para a autopercepção sobre a sua docência. Por outro lado, ao longo da escrita dos diários observou-se que a maioria dos licenciandos buscou realizar reflexões sobre as observações que realizavam na escola campo. A escrita dos diários se mostrou como um instrumento importante no processo de formação de professores.

Recent studies exploring the relationship between DNA damage measured by the comet assay (single-cell gel electrophoresis) and cognitive function in both animal models and humans are reviewed and summarized. This manuscript provides an overview of studies exploring cognitive dysfunction related to DNA damage due to biological ageing process, cancer treatment, adverse environmental or occupational exposures, and prenatal genotoxic exposure. The review confirms the potential of comet assay to further explore the link between DNA damage, as indicative of genomic instability, and cognitive impairment in different research and clinical areas. Analysed studies support, in fact, the significant relationship between DNA damage and cognitive impairment, mainly affecting attention, working memory and executive functions. These cognitive domains are crucial to daily functioning and occupational performance, with important clinical implications. Although evidence support the relationship between DNA damage measured by the comet assay and cognitive function in different settings, further longitudinal research is needed to disentangle the temporal relationship between them over time, and to explore the potential of comet assay-detected DNA lesions to predict response to interventions. Highlights: Review on the link between DNA damage measured by the comet-assay and cognition; Ageing, cancer treatment, hazardous exposures and prenatal DNA damage are included; Studies support association affecting attention, memory and executive functions; Further longitudinal research will help to prevent and delay cognitive decline. This work was funded by the Spanish Ministry of Science and Innovation: MCIN/AEI/10.13039/501100011033 [Grant PID2020- 113788RB-I00], Xunta de Galicia (ED431B 2022/16, ED431F 2017/09), Ministry of Education, Culture and Sport [BEAGAL18/00142 to V.V.], and Ministry of Economy and Competitiveness, co-financed by the European Social Fund [RYC-2015–18394 to L.L-L]. Funding for open access charge: Universidade da Coruna/CISUG. info:eu-repo/semantics/publishedVersion

The comet assay is a widely used test for the detection of DNA damage and repair activity. However, there are interlaboratory differences in reported levels of baseline and induced damage in the same experimental systems. These differences may be attributed to protocol differences, although it is difficult to identify the relevant conditions because detailed comet assay procedures are not always published. Here, we present a Consensus Statement for the Minimum Information for Reporting Comet Assay (MIRCA) providing recommendations for describing comet assay conditions and results. These recommendations differentiate between ‘desirable’ and ‘essential’ information: ‘essential’ information refers to the precise details that are necessary to assess the quality of the experimental work, whereas ‘desirable’ information relates to technical issues that might be encountered when repeating the experiments. Adherence to MIRCA recommendations should ensure that comet assay results can be easily interpreted and independently verified by other researchers., Here, members of the hCOMET COST Action program provide a consensus statement on the Minimum Information for Reporting Comet Assays (MIRCA).

Redox reactions are considered one of the most difficult chemistry subjects to teach and learn. However, this is an important content that permeates several topics and includes many everyday life-related phenomena. To understand the teaching and learning difficulties of the ‘redox reactions’ topic, a systematic literature review was conducted. Initially, 318 articles were mapped, between the years 2000 to 2019, related to the teaching of redox reactions. The inventoried articles were analyzed to identify, in their results, the aforementioned difficulties. Only 54 presented difficulties related to teaching and learning redox reactions. To analyze these articles, the year of publication, the conceptual/procedural difficulties resulting from the study, the researched participants, and the strategies used throughout the data collection were adopted as categories. As a result, the main participants of the investigations were students. It was observed that the research studies favored bachelor degree as the level of education. Moreover, most of the analyzed studies mainly proposed experimentation as teaching strategy for teaching redox reactions. This study points to the need for continuing education courses for chemistry teachers to discuss emerging difficulties, in addition to proposing teaching strategies to remedy these difficulties. Keywords: education proposals, learning difficulties, redox reactions, state of the art

The objective of this study was to analyze visual representations of redox reactions and related content in four Brazilian secondary school chemistry textbooks. The study aimed to identify which representations were used and to evaluate how these representations were linked to one another and to the main text. Data were analyzed regarding representational levels and the degree of relatedness between the different levels and the main text. Further analysis focused on the intended function of images and which curriculum orientation they indicated. The sample was comprised of 286 visual representations. The results showed that most of the visual representations merely served a decorative function and were not explicitly used to further understanding of the content in the main text. The findings indicated that the textbooks in this sample prioritized two separate levels of representation: The macroscopic and the symbolic. Only a few submicroscopic and multilevel representations could be found. The textbook illustrations indicated a strong “structure of the discipline” orientation of the curriculum, which was illustrated with orientations taken from everyday life, technology, and industry. It emphasizes the importance of using illustrations in textbooks, because of its influence on the construction of concepts, in particular the concept of redox reactions. Based on this research, it is possible for chemistry teachers to observe the limitation of these materials and carefully select the textbook used in their curricula. Moreover, the results can contribute to improving the quality of textbooks.

The increased frequency and intensity of forest fires have been concerning populations particularly in countries typically affected by this natural disaster. Portugal has been harshly afflicted by wildfires specially in the north and central regions. In the frontline of forest fire combat there is one of the riskiest occupations in the world – firefighters. Firefighting involves high physical and psychological demanding activities typically performed in hostile environments. The proximity to fire exposes them not only to high temperatures but also to high concentrations of hazardous pollutants, most of which are listed as probable or known carcinogens. Given the above, IARC classified occupational firefighting activity as possibly carcinogenic to humans. However, it is still among the least studied occupations, existing very little information on exposure induced mechanisms that lead to health diseases. Thus, the general aim of Bio4FOX study is to identify a set of (bio)markers for the surveillance of Portuguese Wildland firefighters’ occupational exposure during three phases, pre-, during and post- fire season. Here, we aim to describe the preliminary data on sociodemographic and occupational context of the Bio4Fox study population in the pre-fire season. For the 1st phase of the study were enrolled around 173 wildland firefighters from 14 fire stations located in the northern region of Portugal. Information on sociodemographic data, health status, lifestyle and occupational exposure were obtained via a comprehensive questionnaire. The study group was composed by 144 men and 29 women; the mean age of the group was 37.88±10.82. Most of the firefighters reported to be voluntary (83%; n=144) beginning their activities at young ages; more than half (n=93) started within 17 - 22 years old and 8% (n=14) of the individuals attended firefighters’ activities at earlier ages (12-16 years old). The average length of service as firefighter was 15.87±10.17 years. Around 46% (n=79) claimed to spend more than 10 hours in their duties, while 34% (n=58) and 12% (n=21) spend 8-9hours and < 8 hours, respectively. Concerning their risk perception related to exposure to hazard contaminants, 79% (n=136) believed to be exposed to smoke, gases, and/or particles and 15% (n=25) to solvents (e.g., combustible). Self-reported symptoms (of last 30 days, not related with cold/flu) were: expectoration (14%; n=24), tiredness (13%; n=22), breath difficulty (9%; n=16), cough (8%; n=13) and wheezing (6%; n=10). Our preliminary data describes the sociodemographic factors and occupational activities of a group of Portuguese firefighters before the fire-season. This data will be integrated together with the biological and environmental findings collected over different time points of a wildfire season. Bio4FOX will contribute to the establishment of recommendations/good practices to improve firefighters’ working conditions, as well support the definition of better policies/prevention strategies highly needed in this sector.

publicado em: https://doi.org/10.24840/978-972-752-279-8 Introduction: Worldwide, forest fires are among the most common forms of natural disasters. In the closing years of the last century, there was an increase in the burned area in some parts of the globe, including Europe. Portugal has been particularly affected by large forest fires and mega fires, which have been occurred mainly in the central and northern regions. The proximity of firefighters to fire exposes them to high levels of toxic compounds making this occupation one of the most dangerous and leading International Agency for Research on Cancer to classified occupational firefighting activity as possibly carcinogenic to humans. Up to date, the existing studies are mainly focused on environmental monitoring, existing limited information regarding biomonitoring assessments during real scenarios of wildland fires combat. This study aims to evaluate the impact of firefighting occupational exposure at molecular and cellular levels, considering personal exposure levels. Early-effect biomarkers (e.g., micronucleus, DNA strand breaks and oxidative DNA damage) will be analyzed in order to understand the mechanisms of action through which woodsmoke may impact firefighters' health, including the risk of cancer. Methodology: This ongoing prospective longitudinal study will comprise three different stages, specifically pre-exposure, exposure, and post-exposure to fire season. Around 200 wildland northern Portuguese firefighters will be involved in this study. Characterization of the study population will be conducted via questionnaires. Firefighters' personal exposure levels will be assessed by means of metabolites in exhaled breath, using an artificial olfactory system (e-nose technology). Buccal and urine samples will be used to measure genomic instability through a micronucleus test in buccal epithelial cells and urothelial cells. DNA damage and oxidative DNA damage will be evaluated in peripheral blood lymphocytes using the comet assay. Statistical analysis will be performed to determine the relationship between personal exposure levels to toxic compounds and the early-effect biomarkers over the three different phases of the study. Expected results: The obtained results will support a more accurate and comprehensive assessment of occupational risks among wildland firefighters, crucial to prevent/reduce the associated health impacts. This work will contribute to the establishment of recommendations/good practices to improve firefighters' working conditions, allowing better definitions of policies and prevention strategies highly needed in this sector. info:eu-repo/semantics/publishedVersion

The 3rd Occupational Safety and Health proceedings book is a compilation of the most recent works of students, researchers and professors within the domain of occupational safety and health. The included works are focused on selected topics regarding ergonomics, safety, and health.This proceedings book represents the state of the art and it is mainly based on research carried out at Universities and other research institutions, as well as some case studies. In its scope, this book contains useful and up-to-date information, giving visibility to emerging issues and presenting new solutions in the field of occupational safety and health.The proceedings books is based on selected contributions from the 3rd Doctoral Congress in Engineering, held on the 27th and 28th of June, at Faculty of Engineering of University of Porto, in Porto, Portugal. All the included contributions were revised by, at least, 2 of the 31 international scientific committee members.

The comet assay has become one of the methods of choice for the evaluation and measurement of DNA damage. It is sensitive, quick to perform and relatively affordable for the evaluation of DNA damage and repair at the level of individual cells. The comet assay can be applied to virtually any cell type derived from different organs and tissues. Even though the comet assay is predominantly used on human cells, the application of the assay for the evaluation of DNA damage in yeast, plant and animal cells is also quite high, especially in terms of biomonitoring. The present extensive overview on the usage of the comet assay in animal models will cover both terrestrial and water environments. The first part of the review was focused on studies describing the comet assay applied in invertebrates. The second part of the review, (Part 2) will discuss the application of the comet assay in vertebrates covering cyclostomata, fishes, amphibians, reptiles, birds and mammals, in addition to chordates that are regarded as a transitional form towards vertebrates. Besides numerous vertebrate species, the assay is also performed on a range of cells, which includes blood, liver, kidney, brain, gill, bone marrow and sperm cells. These cells are readily used for the evaluation of a wide spectrum of genotoxic agents both in vitro and in vivo. Moreover, the use of vertebrate models and their role in environmental biomonitoring will also be discussed as well as the comparison of the use of the comet assay in vertebrate and human models in line with ethical principles. Although the comet assay in vertebrates is most commonly used in laboratory animals such as mice, rats and lately zebrafish, this paper will only briefly review its use regarding laboratory animal models and rather give special emphasis to the increasing usage of the assay in domestic and wildlife animals as well as in various ecotoxicological studies. This work was supported by the European Cooperation in Science and Technology (CA COST Action CA15132 – The comet assay as a human biomonitoring tool (hCOMET)). info:eu-repo/semantics/publishedVersion

This study presents a literature review of investigations that analyzed the impacts of the Institutional Program of Initiation to Teaching Scholarship (PIBID) in the education of the triad - pibidians, coordinators and supervisors, in the context of Chemistry teaching. The mapping, between 2008 and 2016, initially cataloged 761 papers in national scientific events related to Science and Chemistry Teaching (ENPEC, ENEQ and RASBQ). The mapping between 2008 and 2018 inventoried 456 publications in the Scielo Data Banks and Capes Portal of Periodicals and 523 papers in the Bank of Thesis and Dissertations of Capes. Of these, only 52, 16 and 20 studies, respectively, analyzed the impact of PIBID on the education of the triad. The PIBID provided student’teachers with experience in the future professional space, participation in scientific events and studies on theoretical references. Supervisors acted as co-educators of the pibidians. Only one of the studies pointed to the impacts on the coordinator's training. Este estudio presenta un levantamiento de la literatura de investigaciones que analizaron los impactos del Programa Institucional de Becas de Iniciación a la Docencia (PIBID) en la formación de la tríada - pibidianos, coordinadores y supervisores, en el contexto de la enseñanza de Química. El mapeo, entre 2008 a 2016, catalogó inicialmente 761 trabajos en los eventos científicos nacionales relacionados a la Enseñanza de Ciencias y Química (ENPEC, ENEQ y RASBQ). El mapeo entre 2008 a 2018 inventarió 456 publicaciones en los Bancos de Datos del Scielo y Portal de Periódicos de la Capes y 523 trabajos en el Banco de Tesis y Disertaciones de la Capes. De estos, sólo 52, 16 y 20 estudios, respectivamente, analizaron el impacto del PIBID en la formación de la tríada. El PIBID propició a los pibidianos la vivencia en el futuro espacio profesional, participación en eventos científicos y estudios sobre referenciales teóricos. Los supervisores actuaron como co-formadores de los pibidianos. Sólo uno de los estudios apuntó los impactos en la formación del coordinador. Este estudo teve por objetivo analisar o impacto do Programa Institucional de Bolsa de Iniciação à Docência (PIBID) na formação da tríade - pibidianos, coordenadores e supervisores, no contexto do Ensino de Química. Mapeou-se a literatura entre 2008 a 2018, em eventos nacionais, artigos, teses e dissertações referentes ao Ensino de Ciências e Química. Foram catalogados inicialmente 761 trabalhos nos eventos, 456 artigos e 523 teses e dissertações. Desses estudos, apenas 52, 16 e 20, respectivamente, referiam-se ao tema de investigação. Realizou-se análise de conteúdo a partir de categorias da literatura e emergentes dos dados. A análise revelou que o PIBID propiciou aos pibidianos a vivência no futuro espaço profissional, participação em eventos científicos e estudos sobre referenciais teóricos; e que os supervisores se reconheceram como coformadores dos pibidianos. Entretanto, somente um dos estudos apontou os impactos na formação do coordenador, revelando lacunas importantes a serem respondidas por estudos futuros. This study aimed to analyze the impact of the Programa Institucional de Bolsa de Iniciação à Docência (PIBID) on the formation of the Triad - Pibdians, coordinators and supervisors, in the context of chemistry teaching. The literature was mapped between 2008 and 2018, in national events, articles, theses and dissertations related to Science and Chemistry Teaching. Initially, 761 event papers, 456 articles and 523 theses and dissertations were cataloged. Of these studies, only 52, 16 and 20, respectively, referred to the research theme. The analysis was performed from literature categories and emerging from the data. The analysis revealed that the PIBID provided the pibidianos experience in the future professional space, participation in scientific events and studies on theoretical references; and that supervisors recognize themselves as co-trainers of the Pibidians. However, only one of the studies pointed to the impacts on the formation of the coordinator, revealing important gaps to be traced by future studies.

[Abstract] The alkaline comet assay, or single cell gel electrophoresis, is one of the most popular methods for assessing DNA damage in human population. One of the open issues concerning this assay is the identification of those factors that can explain the large inter-individual and inter-laboratory variation. International collaborative initiatives such as the hCOMET project - a COST Action launched in 2016 - represent a valuable tool to meet this challenge. The aims of hCOMET were to establish reference values for the level of DNA damage in humans, to investigate the effect of host factors, lifestyle and exposure to genotoxic agents, and to compare different sources of assay variability. A database of 19,320 subjects was generated, pooling data from 105 studies run by 44 laboratories in 26 countries between 1999 and 2019. A mixed random effect log-linear model, in parallel with a classic meta-analysis, was applied to take into account the extensive heterogeneity of data, due to descriptor, specimen and protocol variability. As a result of this analysis interquartile intervals of DNA strand breaks (which includes alkali-labile sites) were reported for tail intensity, tail length, and tail moment (comet assay descriptors). A small variation by age was reported in some datasets, suggesting higher DNA damage in oldest age-classes, while no effect could be shown for sex or smoking habit, although the lack of data on heavy smokers has still to be considered. Finally, highly significant differences in DNA damage were found for most exposures investigated in specific studies. In conclusion, these data, which confirm that DNA damage measured by the comet assay is an excellent biomarker of exposure in several conditions, may contribute to improving the quality of study design and to the standardization of results of the comet assay in human populations. This article is based upon work from COST Action hCOMET CA15132, supported by COST (European Cooperation in Science and Technology www.cost.eu) - STSM fellowships for Mirta Milić (IMROH, EU 19); IMROH, Zagreb, Croatia, Institute for Medical Research and Occupational Health (IMROH), Zagreb, Croatia, and the Ministry of Science, Education and Sports of the Republic of Croatia (Grant No. 022-0222148-2125) (EU4); Cancer Plan for PestiBG; Grant number: no ENV201401(EU 8, EU9); Italian Ministry of Education, University and Research PRIN 2005, prot. 2005058197 and Cariplo Foundation (Milan, Italy), Rif. Pratica 2007-5810 and Rif. Pratica 2010.2303 (EU 18); Associazione Italiana per la Ricerca sul Cancro (AIRC) (IG 2015/17564). (EU19); European Union Integrated Projects New Generis, 6th Framework Programme, Priority 5: Food Quality and Safety; Newborns and Genotoxic Exposure Risks, FOOD-CT-2005-016320 (EU22); ACT project No. 036APy/09 and No. 005DBB/12 (EU 24); FCT-SFRH/BPD/96196/2013, SFRH/BPD/100948/2014, Portugal (EU 26); MZ 2012/8-UKBA-8; VEGA 1/0703/13, APVV 15-0063 (EU30); Xunta de Galicia (XUGA 10605B98; INCITE08PXIB106155PR; ED481B2016/190-0; Grants ED431B2019/02), Spain (EU 32); Grant 01 173034, Ministry of Education, Science and Technological Development of the Republic of Serbia (EU 42); The Centre for Industrial and Technological Development within National Strategic Consortia for Techical Research (Industrial Research diets and food with specific characteristics for elderly, SENIFOOD); University of Navarra LE/97; Physiopathology of Obesity and Nutrition (CIBER Obn); Carlos III Health Research Institute (CB12/03/30002); Ministerio de Economia y Compatitividad (‘Ramón y Cajal’ Programme, RYC-2013-14370) of the Spanish Government for personal support (EU 45); the Ministry of Education, Youth and Sports of the Czech Republic project Healthy Aging in Industrial Environment HAIE (CZ.02.1.01/0.0/0.0/16_019/0000798) which is co-financed by the European Union (European Structural and Investment funds; Operation Programme Research, Development and Education); MYES LO 1508 (EU 46); MICRODIAB Study; ClinicalTrials.org (#NCT02231736) (EU 52); The study was funded by the Italian Ministry for Education, University and Scientific Research (MIUR) - Research No. 2005-062547 (EU14, EU53); Projects financed from Serbian Ministry of Education, Science and Technological Development #11146002, #175035, #173034 (EU 54); Mehr foundation organisation, UK (EU 55); MCTI/CNPQ No. 01/2016-Universal; FAPESC No. 09/2015; MEC/MCTI/CAPES/CNPQ/FAPS/ No. 09/2014, Brazil (CSA 6); the National Nuclear Energy Agency of Indonesia (Badan Tenaga Nuklir Nasional) with contract number 080.01.06 3447.001 001.052.A (AS4); Slovak Grant Agency (APVT-21 013202, APVT-21- 017704); Ministry of Health, Slovak Republic (2005/43-SZU-21, 2006/07- SZU-02 MZ SR, 2005/42-SZU-20

Asthma is one of the most common respiratory diseases, with airway inflammation as the most prominent pathological feature. Although originally believed to be a single disease, it is now recognized as a complex of multiple phenotypes, with different degrees of severity and treatment responses. The severe inflammatory state becomes apparent when reactive oxygen species overwhelm the antioxidant defense. Thus the oxidant-antioxidant imbalance plays an important role in airway inflammation. It is well documented the role of oxidative stress (OS) in the increase of chromosome instability (CI), and, consequently, in cancer predisposition. So it is important to carry out studies in order to establish limits for harmful effects with carcinogenic potential. The aim of this study was to evaluate cellular levels of OS-related CI in asthma patients and the possible protective effect of antioxidants. For that purpose, spontaneous and 1,2,3,4-diepoxybutane (DEB)-induced lymphocyte cultures from patients with mild and severe asthma were performed. Lymphocyte cultures from healthy donors, at the same conditions, were used as control. Antioxidant-enriched (N-Acetylcysteine+α-lipoic acid) lymphocyte cultures from severe patients were posteriorly performed. A hundred metaphases per culture were scored in order to estimate the relative frequency of CI. Our results showed that lymphocytes from severe asthma patients had a significant increase of CI, both in spontaneous and DEB-induced cultures. However, in lymphocytes from mild asthma patients there were no significant differences compared to controls. This suggests that in patients with severe asthma, subjected to extreme OS conditions, a possible genotoxic effect may occur at the cellular level. When the lymphocytes from these patients were subjected to an antioxidant treatment, a significant and consistent decrease in levels of CI was observed. Understanding how CI due to exposure to OS correlates to asthma patients clinical characteristics may be pivotal to the design of preventive measures or patient-specific treatments.

This research consisted of the analysis of Dissertations and Theses (DTs) that investigated both teaching knowledge and/or teaching wisdom in Chemistry Teaching from 2010 to 2019 available in Biblioteca Digital Brasileira de Teses e Dissertações—BDTD (Brazilian Digital Library of Theses and Dissertations) and Catálogo de Teses e Dissertações da Capes ((Coordenação de Aperfeiçoamento Pessoal de Nível Superior) (Capes Dissertations and Theses Catalog). This research is seen as a state of knowledge. The search terms applied were ‘teaching knowledge’ and ‘teaching wisdom’. At first, 1.125 DTs were found containing the given search terms. However, only 64 investigated teaching knowledge and wisdom in Chemistry Teaching. The analysis of the DTs was performed through the investigation of content and emerging categories. Out of the 57 DTs, 15,6% based on teaching knowledge, 28% based on teaching wisdom, 36% distinguished the concepts of knowledge and wisdom, and 20,3% did not distinguish them. The theoretical literature review of those studies relied mostly on the works of Clermont Gauthier, Maurice Tardif, and Lee Shulman. The studies focused mainly on investigating teaching wisdom to the detriment of teaching knowledge. Esta investigación se basó en el análisis de Tesis y Disertaciones (TDs) que investigaron el conocimiento docente y los saberes docente en el área de la enseñanza de química en el período de 2010 a 2019 en la Biblioteca Digital Brasileña de Tesis y Disertaciones (BDTD) y en el Catálogo de Tesis y Disertaciones de Capes (Coordenação de Aperfeiçoamento Pessoal de Nível Superior). Este trabajo aparece como estado de conocimiento. En el proceso de búsqueda se adoptaron las palabras clave: “conocimiento docente” y “saberes docentes”. Inicialmente, se identificaron 1.125 TDs con estas palabras clave, sin embargo, solo 64 investigaron el conocimiento y/o saberes docentes en la enseñanza de química. Para el análisis de las TDs, se adoptó el análisis de contenido y las categorías emergentes. De los 64 TDs, de ese total el 15,6% se basaron en conocimientos docentes, el 28% en saberes docentes, el 36% diferenciaban conocimiento y saberes y el 20,3% de las TDs no realizaban esa diferenciación conceptual. Las investigaciones adoptaron como base teórica principalmente a Clermont Gauthier, Maurice Tardif y Lee Shulman. El enfoque de las investigaciones fue principalmente investigar el saber de la enseñanza a expensas del conocimiento docente. Esta pesquisa baseou-se na análise de Teses e Dissertações (TDs) que investigaram o conhecimento docente e os saberes docentes na área de ensino de química no período de 2010 a 2019 na Biblioteca Digital Brasileira de Teses e Dissertações (BDTD) e no Catálogo de Teses e Dissertações da Capes (Coordenação de Aperfeiçoamento Pessoal de Nível Superior). Este trabalho figura como estado do conhecimento. No processo de busca adotou-se as palavras-chave: “conhecimento docente” e “saberes docentes”. Inicialmente foram identificadas 1.125 TDs com essas palavras-chaves, contudo apenas 64 investigaram o conhecimento e/ou saberes docentes/professores no ensino de química. Para a análise das TDs adotou-se a análise de conteúdo e categorias emergentes. Das 64 TDs, desse total 15,6 % fundamentaram-se no conhecimento docente, 28% nos saberes docentes, 36% diferenciavam conhecimento e saberes e 20,3% das TDs não realizavam essa diferenciação conceitual. As pesquisas adotavam como base teórica principalmente Clermont Gauthier, Maurice Tardif e Lee Shulman. O foco das pesquisas foram principalmente investigar o saber docente em detrimento do conhecimento docente.

In October 2017, hundreds of wildfires ravaged the forests of the north and centre of Portugal. The fires were fanned by strong winds as tropical storm Ophelia swept the Iberian coast, dragging up smoke (together with Saharan dust from north-western Africa) into higher western European latitudes. Here we analyse the long-range transport of particulate matter (PM10) and study associations between PM10 and short-term mortality in the Portuguese population exposed to PM10 due to the October 2017 wildfires, the worst fire sequence in the country over the last decades. We analysed space- and ground-level observations to track the smoke plume and dust trajectory over Portugal and Europe, and to access PM10 concentrations during the wildfires. The effects of PM10 on mortality were evaluated using satellite data for exposure and Poisson regression models. The smoke plume covered most western European countries (including Spain, France, Belgium and the Netherlands), and reached the United Kingdom, where the population was exposed in average to an additional PM10 level of 11.7 µg/m3 during seven smoky days (three with dust) in relation to the reference days (days without smoke or dust), revealing the impact of the wildfires on distant populations. In Portugal, the population was exposed in average to additional PM10 levels that varied from 16.2 to 120.6 µg/m3 in smoky days with dust and from 6.1 to 20.9 µg/m3 in dust-free smoky days. Results suggest that PM10 had a significant effect on the same day natural and cardiorespiratory mortalities during the month of October 2017. For every additional 10 µg/m3 of PM10, there was a 0.89% (95% confidence interval, CI, 0-1.77%) increase in the number of natural deaths and a 2.34% (95% CI, 0.99-3.66%) increase in the number of cardiorespiratory-related deaths. With rising temperatures and a higher frequency of storms due to climate change, PM from Iberian wildfires together with NW African dust will tend to be more often transported into Northern European countries, which may carry health threats to areas far from the ignition sites. SA was supported by the Portuguese Foundation for Science and Technology (FCT), Portugal [grant number SFRH/BPD/109382/2015]. MT has received funding from the Spanish Ministry of Science, Innovation and Universities, Spain, through the project PREDFIRE (RTI2018-099711-J-I00), which is co-financed with the European Regional Development Fund (ERDF/FEDER). SC was supported by FCT [grant number SFRH/BPD/100948/2014]. The authors acknowledge Project REPAIR-CGL2014-59677-R and ACEX-CGL2017-87921-R of the Spanish Ministry of the Economy and Competitiveness and the FEDER European program for their support to conduct this research. Further support was granted by projects: (i) POCI-01-0145-FEDER-006939 (LEPABE – UID/EQU/00511/2013) funded by the European Regional Development Fund (ERDF), through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds, through FCT - Fundação para a Ciência e a Tecnologia; (ii) NORTE-01-0145-FEDER-000005-LEPABE-2-ECO-INNOVATION, supported by North Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the ERDF. info:eu-repo/semantics/publishedVersion

This research aimed to carry out the development and analysis of reliability to identify and record the notion of Chemical Kinetics of undergraduate and graduate students from the Chemistry Licentiate Degree. This is a quantitative research. In this regard, a Likert Scale Survey was devised containing 18 questions and the multiple-choice options ‘strongly disagree’, ‘somewhat disagree’, ‘neither agree nor disagree’, ‘somewhat agree’, ‘strongly agree’ to identify the level of agreement of the respondent with each statement. Those statements were developed taking into account surveys on Kinetics teaching and were theoretically validated by experts in the field. Subsequently, the semantic validation was performed with potential survey respondents so that they pointed out their understandings about the questions. Changes were made to the survey based on the experts’ suggestions. Accordingly, its final draft consisted of the initial structure, except for the readjustment of the conceptual part of some questions as well as for the exclusion of the multiple-choice option ‘neither agree nor disagree’. The survey was answered by 55 respondents, including undergraduate and graduate students from the Chemistry Licentiate Degree from eight Brazilian public institutions. In order to analyze the reliability of the respondents’ answers, Cronbach's Alpha was applied. The reliability value of alpha for the entire instrument was 0.64. After purifying it, contemplating only 12 questions from thematic groups B and C, its reliability was 0,94, suggesting high reliability and that the instrument made up of those questions is reliable and has consistent measurements. Esta investigación tuvo como objetivo realizar la construcción y análisis de confiabilidad con el objetivo de identificar y registrar las concepciones de estudiantes de pregrado y egrasados en el curso de química en cinética química. Esta investigación es cuantitativa. En este sentido, se elaboró un cuestionario Likert compuesto por 18 cuestiones y las escalas totalmente en desacuerdo, parcialmente en desacuerdo, ni de acuerdo ni en desacuerdo, parcialmente de acuerdo y totalmente de acuerdo, para identificar el grado de concordancia del participante con cada afirmación. Estas afirmaciones fueron construidas considerando investigaciones sobre la enseñanza de la cinética y validados teóricamente por expertos en el campo. Posteriormente, se llevó a cabo una validación semántica, con posibles participantes de la investigación, para pontuar sus entendimientos sobre el cuestionario. Los cambios al cuestionario se realizaron debido a las sugerencias de los expertos. En consecuencia, la versión final del cuestionario constó de la misma estructura inicial, excepto por el reajuste de la parte conceptual de algunas cuestiones y la exclusión de la escala ni de acuerdo ni en desacuerdo. El cuestionario fue respondido por 55 participantes, incluidos estudiantes de pregrado y egresados del curso de licenciatura en química de ocho instituciones públicas brasileñas. Para analizar la confiabilidad de las respuestas dadas por los participantes, se adoptó el Alfa de Cronbach. Para todo el instrumento, el valor de confiabilidad del alfa fue de 0.64 y posteriormente se realizó la depuración del instrumento, considerando sólo 12 cuestiones, pertenecientes a los bloques temáticos B y C, la confiabilidad del instrumento fue de 0.94, sugiriendo una alta confiabilidad y que el instrumento constituido por estas cuestiones es confiable y tiene mediciones consistentes. Esta pesquisa teve como objetivo realizar a construção e análise da confiabilidade destinado à identificação e registro das concepções de licenciandos e egressos do curso de química sobre cinética química. Esta pesquisa figura como quantitativa. Nesse sentido, foi elaborado um questionário Likert constituído por 18 questões e as escalas discordo totalmente, discordo parcialmente, nem concordo e nem discordo, concordo parcialmente e concordo totalmente, para identificar o grau de concordância do participante com cada afirmativa. Essas afirmativas foram construídas considerando-se pesquisas sobre o ensino de cinética e validadas teoricamente por especialistas na área. Posteriormente, realizou-se a validação semântica, com possíveis participantes da pesquisa, para que pontuassem suas compreensões sobre o questionário. As mudanças no questionário foram realizadas em virtude das sugestões dos especialistas. Em consonância, a versão final do questionário foi constituída pela mesma estrutura inicial, exceto pela readequação da parte conceitual de algumas questões e da exclusão da escala nem concordo e nem discordo. O questionário foi respondido por 55 participantes, entre licenciandos e egressos do curso de licenciatura em química de oito instituições públicas brasileiras. Para analisar a confiabilidade das respostas concedidas pelos participantes, adotou-se o Alfa de Cronbach. Para todo o instrumento valor de confiabilidade do alfa foi de 0.64 e posteriormente a realização da purificação do instrumento, considerando apenas 12 questões, pertencentes aos blocos temático B e C a confiabilidade do instrumento foi de 0.94, sugerindo uma alta confiabilidade e que o instrumento constituído por essas questões é confiável e tem medições consistentes.

Genome instability denotes an increased tendency to alterations in the genome during cell life cycle, driven by a large variety of endogenous and exogenous insults. Ageing is characterized by the presence of damage to various cellular constituents, but genome alterations, randomly accumulating with age in different tissues, constitute the key target in this process, and are believed to be the main factor of ageing. Age-related failure of DNA repair pathways allows DNA lesions to occur more frequently, and their accumulation over time contributes to the age-associated decrease in genome integrity in somatic cells. The micronucleus (MN) test is one of the most widely used assays to evaluate genomic instability in different surrogate tissues. A large number of studies has consistently shown a progressive increase in MN frequency with age, starting from very young age groups onwards. Therefore, MN frequency is a suitable biomarker of genomic instability in ageing. Frailty is a multidimensional geriatric syndrome of unsuccessful ageing, characterized by decreased biological reserves and increased vulnerability to external stressors, involving a higher risk of negative health outcomes. Although there is a well-founded belief that genome instability is involved in the frailty syndrome, only two studies investigated the relationship between MN frequency and frailty, not allowing to draw a definite conclusion on the utility of this biomarker for frailty detection. The use of MN and other genomic biomarkers in the detection and follow-up of patients affected by or at risk of frailty has the potential to accumulate evidence on the clinical impact of this approach in the identification and control of frailty in older people. This research was funded by Xunta de Galicia [grant number ED431B 2019/02], Ministerio de Educación, Cultura y Deporte [grant number BEAGAL18/00142 to V.V.], and Fundação para a Ciência e a Tecnologia [grant number SFRH/BPD/100948/2014 to S.C.].

Firefighters represent one of the riskiest occupations, yet due to the logistic reasons, the respective exposure assessment is one of the most challenging. Thus, this work assessed the impact of firefighting activities on levels of urinary monohydroxyl-polycyclic aromatic hydrocarbons (OHPAHs; 1-hydroxynaphthalene, 1-hydroxyacenaphthene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenzo(a)pyrene) and genotoxic/oxidative-effect biomarkers (basal DNA and oxidative DNA damage) of firefighters from eight firehouses. Cardiac frequency, blood pressure and arterial oxygen saturation were also monitored. OHPAHs were determined by liquid-chromatography with fluorescence detection, while genotoxic/oxidative-effect biomarkers were assessed by the comet assay. Concentrations of total OHPAHs were up to 340% higher (p ≤ 0.05) in (non-smoking and smoking) exposed workers than in control subjects (non-smoking and non-exposed to combat activities); the highest increments were observed for 1-hydroxynaphthalene and 1-hydroxyacenaphthene (82-88% of ∑OHPAHs), and for 2-hydroxyfluorene (5-15%). Levels of biomarker for oxidative stress were increased in non-smoking exposed workers than in control group (316%; p ≤ 0.001); inconclusive results were found for DNA damage. Positive correlations were found between the cardiac frequency, ∑OHPAHs and the oxidative DNA damage of non-smoking (non-exposed and exposed) firefighters. Evidences were raised regarding the simultaneous use of these biomarkers for the surveillance of firefighters' health and to better estimate the potential short-term health risks. Highlights: Urinary PAH metabolites and genotoxic/oxidative effects were assessed in firefighters; Levels of total PAH metabolites were increased up to 340% in exposed subjects; Urinary 1OHNaph+1OHAce, and 2OHFlu were the compounds with the highest increments; Firefighting and tobacco smoke raised the oxidative DNA damage in exposed subjects; Cardiac frequency, PAH metabolites and DNA damage can be used for health surveillance. This work received financial support from European (FEDER funds through COMPETE) and National funds through Fundação para a Ciência e Tecnologia for projects UID/QUI/50006/2019 and PCIF/SSO/ 0017/2018, and in the scope of the P2020 Partnership Agreement Project POCI-01-0145-FEDER-006939 (LEPABE). K. Slezakova and S. Costa were supported by the grants SFRH/BPD/105100/2014 and SFRH/BPD/100948/2014, respectively. info:eu-repo/semantics/publishedVersion

Frailty is an age-related syndrome expected to increase over the next decades. This syndrome has been identified to be the most common condition leading to disability, institutionalisation and death in the elderly. The aim of this pilot study is to investigate a possible link between frailty status, biomarkers and environmental exposures. A group of 71 older adults (≥65 years old) was engaged in this study. The study population was classified as 45.1% robust, 45.1% pre-frail and 9.8% frail. A significant higher prevalence of second-hand smokers was found in the pre-frail group when compared to robust. Furthermore, a higher prevalence of robust individuals was found among those consuming home-produced vegetables and water from well/springs. Significant differences were found between data collected in a lifetime exposure questionnaire (LTEQ) and the levels of genotoxicity endpoints and the mercury levels analysed regarding some exposure-related parameters, namely, smoking habits, intake of home-produced vegetables and the use of pesticides in agriculture. Understanding if the way we live(d) or worked can impact the way we age are important questions to be explored. Data obtained in this pilot study encourage further studies on this matter, exploring the role of exposures history and its impact on health. Highlights: Frailty is an age-related syndrome expected to increase over the next years; A prevalence of second-hand smokers was found in the pre-frail group; Home-produced vegetables consumers had lower %TDNA levels; Exposure-related factors should be included when studying disease aetiology; The way we live(d) or worked may have an impact on the way we age. Armanda Teixeira-Gomes and Solange Costa are supported by Fundação para a Ciência e Tecnologia (FCT-MCTES), and by the European Social Fund, through Programa Operacional Capital Humano (POCH), under the grants SFRH/BD/121802/2016 and SFRH/BPD/ 100948/2014, respectively; Vanessa Valdiglesias is supported by Beatriz Galindo Research FellowshipBEAGAL18/00142. The authors also acknowledge the contribution of the COST Action CA15132 “The comet assay as a human biomonitoring tool (hCOMET)” to this study info:eu-repo/semantics/publishedVersion

Este trabalho apresenta os desdobramentos de um estudo que buscou construir o perfil conceitual de interdisciplinaridade. Foram entrevistados 12 professores de diferentes áreas de um curso de Licenciatura em Quí­mica, que prevê uma formação interdisciplinar de seus licenciandos. O roteiro da entrevista semiestruturada tinha por objetivo emergir as concepções dos docentes sobre o conceito de interdisciplinaridade. As zonas do perfil conceitual que fundamentaram a análise foram a Intensidade de Troca, a Busca, a Atitude e a Hí­brida. Os resultados suscitam que a zona do perfil mais acessada pelos professores foi a Hí­brida, indicando uma junção que envolve o conceito de interdisciplinaridade com um ou mais ní­veis de integração. Infere-se a constatação dos professores de que a metodologia interdisciplinar possibilita um conhecimento mais elevado, entretanto, há importantes dificuldades a serem superadas para desenvolver um ensino com este ní­vel de integração entre as disciplinas.

This research sought to analyze the reliability of an instrument to measure teacher knowledge of a group of pre-service chemistry teachers participating in the Institutional Program for Scholarships for Beginner Teachers in Brazil (PIBID).. Thus, it was analyzed the evaluation of a group of students about the Pedagogical Content Knowledge (PCK) of five pre-service chemistry teachers from the program. Accordingly, an instrument containing 28 statements and an open question was applied to a group of 70 students from a public school to whom the pre-service teachers had applied their didactic proposals. The purpose of the instrument was to measure the perception of the students' about the components of the teacher knowledge (Subject Matter Knowledge - SMK, Instructional Representation and Strategies - IRS, Instructional Objective and Context - IOC and Knowledge of Students’ Understanding - KSU) of the pre-service teachers. The results of the analysis revealed that the instrument about teacher’s knowledge has a high reliability based on the alpha Cronbach values. The results of the alpha coefficient for the pre-service teachers were all above 0.9 suggesting that the instrument is reliable and has consistent measurements. Regarding to the exploratory analysis, the main scale in the PCK evaluation of the undergraduates was four which means that the students consider that the aspects related to the SMK, IRS, IOC and KSU are frequently present in the classes of the future teachers. Keywords: instrument reliability, PIBID, redox reactions, teaching knowledge, PCK.