Microbial evaluation of full-scale wastewater treatment plants by microscopy survey and chemometric analysis

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Activated sludge (AS) systems, are constituted by living organisms, mainly bacteria (floc-forming and filamentous), protozoa and metazoa. The later play an important role on grazing bacteria, and are known to be dependent on the working operational parameters (incoming effluent, dissolved oxygen, nitrification, hydraulic and sludge retention times, transient phenomena, etc.) and the system itself (conventional activated system – CAS, oxidation ditch – OD, trickling filter – TF, etc.). Floc-forming bacteria, such as aerobic heterotrophic, autotrophic (nitrifying and sulfur-oxidizing), denitrifying, sulfatereducing and phosphate accumulating bacteria (PAO), are the main organisms responsible for pollution reduction in AS systems. On the other hand, the major role played by filamentous bacteria, rests on the establishment of the microbial aggregates structure, a key feature regarding sludge settling ability. It is known that AS systems are prone to be affected by bulking, foaming, pin point flocs and dispersed growth occurrences, causing poor sludge settling abilities and affecting the wastewater treatment plant (WWTP) performance. In fact, an excess of filamentous bacteria, resulting in filamentous bulking or foaming events, or a shortage, resulting in dispersed growth or pinpoint flocs formation, leads to settling problems in the secondary clarifier. Furthermore, it is possible to establish a close correlation between the predominance of certain protozoa and metazoa taxa, several AS systems operational and settling problems occurrences. [...]info:eu-repo/semantics/publishedVersio

Revisiting the HPLC-FLD method to quantify paralytic shellfish toxins: C3,4 quantification and the first steps towards validation

Paralytic shellfish toxins (PSTs) are a large group of biotoxins that cause paralytic shellfish poisoning. Their appearance in natural waters and their ingestion by aquatic species have a huge socio-economic impact, whereby their monitoring is of the upmost relevance to minimize the consequences. For earlier detection and faster response/action by stakeholders, validation of adjusted analytical methods, particularly for lower concentration levels, is important. This work proposes a derived High-Performance Liquid Chromatography method, with fluorescence detection (HPLC-FLD). The main differences from the official method are the size of the HPLC column and the gradient elution conditions. It covers the current eleven certified reference materials (CRM) available on the market, including the most recent—C3,4. This first calibration report for C3,4 suggests limits of detection (LOD) and limits of quantification (LOQ) of 6 nM and 19 nM (~5 µg STX.2HCl eqv./kg and 17 µg STX.2HCl eqv./kg), respectively. For the remaining CRM, LODs ranged between 3 and 28 nM (~0.9 and 127 µg STX.2HCl eqv./kg), while LOQs varied between 11 and 94 nM (~3 and 409 µg STX.2HCl eqv./kg, considering toxicity equivalency factors (TEFs) reported by EFSA).info:eu-repo/semantics/publishedVersio

Microbial-based evaluation of foaming events in full-scale wastewater treatment plants by microscopy survey and quantitative image analysis

Activated sludge systems are prone to be affected by foaming occurrences causing the sludge to rise in the reactor and affecting the wastewater treatment plant (WWTP) performance. Nonetheless, there is currently a knowledge gap hindering the development of foaming events prediction tools that may be fulfilled by the quantitative monitoring of AS systems biota and sludge characteristics. As such, the present study focuses on the assessment of foaming events in full-scale WWTPs, by quantitative protozoa, metazoa, filamentous bacteria, and sludge characteristics analysis, further used to enlighten the inner relationships between these parameters. In the current study, a conventional activated sludge system (CAS) and an oxidation ditch (OD) were surveyed throughout a period of 2 and 3 months, respectively, regarding their biota and sludge characteristics. The biota community was monitored by microscopic observation, and a new filamentous bacteria index was developed to quantify their occurrence. Sludge characteristics (aggregated and filamentous biomass contents and aggregate size) were determined by quantitative image analysis (QIA). The obtained data was then processed by principal components analysis (PCA), cross-correlation analysis, and decision trees to assess the foaming occurrences, and enlighten the inner relationships. It was found that such events were best assessed by the combined use of the relative abundance of testate amoeba and nocardioform filamentous index, presenting a 92.9 % success rate for overall foaming events, and 87.5 and 100 %, respectively, for persistent and mild events

Walking Your LiDOG: A Journey Through Multiple Domains for LiDAR Semantic Segmentation

The ability to deploy robots that can operate safely in diverse environments is crucial for developing embodied intelligent agents. As a community, we have made tremendous progress in within-domain LiDAR semantic segmentation. However, do these methods generalize across domains? To answer this question, we design the first experimental setup for studying domain generalization (DG) for LiDAR semantic segmentation (DG-LSS). Our results confirm a significant gap between methods, evaluated in a cross-domain setting: for example, a model trained on the source dataset (SemanticKITTI) obtains $26.53$ mIoU on the target data, compared to $48.49$ mIoU obtained by the model trained on the target domain (nuScenes). To tackle this gap, we propose the first method specifically designed for DG-LSS, which obtains $34.88$ mIoU on the target domain, outperforming all baselines. Our method augments a sparse-convolutional encoder-decoder 3D segmentation network with an additional, dense 2D convolutional decoder that learns to classify a birds-eye view of the point cloud. This simple auxiliary task encourages the 3D network to learn features that are robust to sensor placement shifts and resolution, and are transferable across domains. With this work, we aim to inspire the community to develop and evaluate future models in such cross-domain conditions.Comment: Accepted at ICCV 202

Relação entre a síndrome da apneia obstrutiva do sono e o bruxismo: uma revisão sistemática da literatura

The aim of this study was analyze, through a systematic review of literature of clinical trials, the relationship between obstructive sleep apnea and bruxism, seeking to verify a possible causal association between these two changes. The following terminology was searched in PubMed/MEDLINE database: “Sleep apnea AND bruxism”, “Obstructive sleep apnea AND bruxism”, “Sleep apnea AND sleep bruxism”, “Obstructive sleep apnea AND sleep bruxism”. The search resulted in a total of 264 articles, which were analyzed according to the abstract, applying the following the inclusion criteria: treat yourself to a clinical trial; have been performed in humans; was published in the eortuguese, english or spanish language; addressed the obstructive sleep apnea syndrome (OSAS) with bruxism, without association with other diseases; and have been published in the last 30 years. From a total of nine articles selected for full reading, only four articles were in conform to all the inclusion criteria. In all studies, the highest prevalence in the diagnosis of OSAS concomitant to bruxism was male. Only one study evaluated the association of both disorders in children, showing that there is not significant difference in the prevalence of sleep-disordered breathing at that age. It was possible to conduct a full comparison as to the effectiveness of the means used for diagnosis of OSAS and concomitant bruxism. However, it was not possible to make the comparison of results, since the sample, the methodology, diagnostic methods and the achievement of the results were different. All studies evaluated the association between OSAS and bruxism and it was observed that there is an association between the remission of episodes of apnea/hypopnea and occurrence of bruxism events. Thus, there should be a standardization of diagnostic methods for a better comparison between the results and further studies should be conducted to assess the relationship between patient with Obstructive Sleep Apnea Syndrome and bruxism habit during sleep.NenhumaO objetivo deste trabalho foi avaliar, através de uma revisão sistemática da literatura de trabalhos clínicos, a relação entre a apneia obstrutiva do sono e o bruxismo, procurando-se verificar uma possível associação causa-efeito entre essas duas alterações. Foi utilizada a base de dados PubMed/MEDLINE com os termos: “Sleep apnea AND bruxism”, “Obstructive sleep apnea AND bruxism”, “Sleep apnea AND sleep bruxism”, “Obstructive sleep apnea AND sleep bruxism”. A busca resultou em um total de 264 artigos, os quais foram analisados de acordo com o resumo, aplicando-se os seguintes critérios de inclusão: tratar-se de um estudo clínico; ter sido realizado em seres humanos; ter sido publicado no idioma português, inglês ou espanhol; ter abordado a síndrome da apneia obstrutiva do sono (SAOS) juntamente com o bruxismo, sem associação com outras doenças; e ter sido publicado nos últimos 30 anos. De um total de nove artigos selecionados para a leitura completa, apenas quatro artigos se encaixaram nos critérios de inclusão. Em todos os estudos, a maior prevalência no diagnóstico da SAOS concomitante ao bruxismo foi no sexo masculino. Apenas um estudo avaliou a associação de ambos os distúrbios em crianças, demonstrando que não há diferença significativa na prevalência dos distúrbios respiratórios do sono nessa idade. Foi possível realizar uma comparação total quanto à efetividade dos meios utilizados para diagnóstico de SAOS e bruxismo concomitante. No entanto, não foi possível fazer o confronto dos resultados, pois a amostra, a metodologia, os métodos de diagnóstico e a obtenção dos resultados foram diferentes. Todos os trabalhos avaliaram a associação entre a SAOS e o bruxismo e observou-se que há associação entre a remissão dos episódios de apneia/hipopneia e ocorrência de eventos de bruxismo. Conclui-se que deve haver uma padronização dos métodos de diagnósticos para uma melhor comparação entre os resultados e mais estudos devem ser realizados para avaliar a relação que existe entre o paciente portador da Síndrome da Apneia Obstrutiva do Sono e do hábito de bruxismo durante o sono

Emergency Remote Education in the Perception of On-Site Accounting Sciences Students during the Covid-19 pandemic

O estudo objetivou investigar a percepção de acadêmicos presenciais do curso de ciências contábeis de uma universidade pública que adotou o ensino remoto emergencial durante a pandemia de Covid-19 no Brasil, ressaltando-se os aspectos que favorecem ou dificultam a aprendizagem. Foi realizado um estudo qualitativo e descritivo, com dados coletados mediante 4 grupos focais com a participação de 80 alunos de um curso presencial de graduação em ciências contábeis. Os resultados indicam que os alunos percebem como aspectos facilitadores do ensino remoto os fatores estruturais (flexibilização nos prazos para entrega de atividades), pessoais e coletivos (autonomia no processo de aprendizagem) e didático-pedagógicos (uso de metodologias ativas pelo professor). Quanto aos aspectos que dificultam a aprendizagem, destacam-se os fatores externos (falta de acesso à internet), individuais (não manter rotina de estudos e elevação do nível de estresses) e práticas docentes tradicionais (aulas monótonas por videoconferência). Por fim, observa-se uma visão otimista para tendências futuras, com alterações nos aspectos humanos (mudança de paradigma do papel do aluno), institucionais (maior utilização da tecnologia) e formativos (uso de metodologias ativas). Conclui-se que a utilização de metodologias ativas no aspecto didático e pedagógico eleva a participação do número de alunos nas aulas remotas e melhora a qualidade da aprendizagem. O estudo pode contribuir com as instituições de ensino que adotam o ensino remoto emergencial para continuidade das atividades acadêmicas em períodos de crise, bem como aos docentes que planejam suas atividades, ressaltando-se o papel do professor e a importância das metodologias ativas na construção do conhecimento.This study aimed to investigate the perception of on-site students of the Accounting Sciences Program of a public university that adopted emergency remote learning during the Covid-19 pandemic in Brazil, highlighting the aspects that favor or hinder learning. A qualitative and descriptive study was carried out, with data collected through 4 focus groups with the participation of 80 students from an on-site undergraduate program in Accounting Sciences. The results indicate that the students perceive the structural factors (flexibility in the deadlines for delivery of activities), personal and collective factors (autonomy in the learning process) and didactic-pedagogical factors (use of active methodologies by the professor) as facilitating aspects of the remote education. As for the aspects that hinder learning, we highlight external factors (lack of internet access), individual factors (not maintaining a study routine and increased stress levels) and traditional remote education (monotonous videoconference classes). Finally, an optimistic vision for future trends is observed, with changes in the human aspects (change of paradigm of the student's role), institutional aspects (greater use of technology) and formative aspects (use of active methodologies). It is concluded that the use of active methodologies in the didactic and pedagogical aspect raises the participation of the number of students in remote classes and improves the quality of learning. This study can contribute to educational institutions that adopt emergency remote education for continuity of academic activities in periods of crisis, as well as to professors who plan their activities. It emphasizes the role of the professor and the importance of active methodologies in the development of knowledge

Toward a psychology of Jiu-jitsu: phenomenological analysis of the ways to combat in practitioner's experience

[EN] A psychological perspective of martial arts necessarily involves the understanding of personal development sought for them

Cation-exchange resin applied to paralytic Shellfish toxins depuration from Bivalves exposed to Gymnodinium catenatum

The accumulation of marine biotoxins in shellfish and their consumption causes serious food safety problems, threatening human health and compromising the availability of protein-based food. It is thus urgent to develop methodologies for the detoxification of live bivalves, avoiding their economic and nutritional devaluation. In this context, we tested an adsorption mechanism of paralytic shellfish toxins (PST) based on a cation-exchange resin. The first studies using cultures of Gymnodinium catenatum (natural producers of PST) showed a decrease of about 80% in overall toxicity after 48 h. Interestingly, we found that the toxins are adsorbed differently, with toxins’ structural features playing a part in the adsorption capacity via steric hindrance, electronic effects, or the extent of positive charge density (e.g., dcSTX). The positive effect of the resin in accelerating PST clearance from live mussels (Mytilus edulis) is not evident when compared to resin-free clearance; nevertheless, relevant information could be gathered that will facilitate further in vivo studies. Several factors appear to be at play, namely the competition of natural substances (e.g., salts, organic matter) for the same binding sites, the blocking of pores due to interactions between molecules, and/or difficulties in resin absorption by mussels. Additionally, the present work revealed the ability of mussels to neutralize pH and proposes bioconversion reactions among the PST molecules.LA/P/0101/2020MAR-01.03.01-FEAMP0049info:eu-repo/semantics/publishedVersio

Environmental impact and biological removal processes of pharmaceutically active compounds: The particular case of sulfonamides, anticonvulsants and steroid estrogens

Pharmaceutically active compounds (PhACs) have recently received wide attention in the scientific community due to their extensive consumption for human health and consequent discharge to the environment. Release of PhACs into the environment, even in trace amounts, can cause serious environmental damage. This has become a major concern and their removal from water sources is a priority. Although a few PhACs are efficiently removed in wastewater treatment plants (WWTPs), others remain recalcitrant, and their release is causing damage. In this review, the current state of the art on the biological removal processes of sulfonamide sulfamethoxazole (SMX), the anticonvulsant carbamazepine (CBZ), and steroid estrogens 17-estradiol (E2) and 17-ethinylestradiol (EE2) are discussed, along with their environmental impact. Other systems beyond activated sludge, such as membrane bioreactors, enzymatic membrane reactors, fungi treatments and hybrid systems are also becoming of major interest and are being evaluated for the removal of these compounds. Future perspectives are addressed.Cristiano Leal is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors thank the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684) 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