2,589 research outputs found
What did we learn after the 2020 pandemic? Seroprevalence of SARS-CoV-2 infection in a North region of Portugal during 3rd lockdown
Background: Serological studies of antibody prevalence in response to infection with the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are useful to monitor the epidemic progression of the disease and to evaluate infection rates. In this study, we estimated the prevalence of anti-SARS-CoV-2 antibodies (IgM and IgG) in a Portuguese sub-district, during National lockdown - January-March 2021.Methods: In the seroepidemiological survey participants were tested for SARS-CoV-2 antibodies (IgM and IgG), in blood samples. The estimated seroprevalence and results were stratified by age, gender, education, occupational exposure, symptoms and previous SARS-CoV-2 infection.Results: Seroprevalence was 41.3%, (15.7% IgG positive, 11.6% IgM positive and 14% positive for both). The majority (74%) of the participants were working presentially and did the serological assay because they had either symptoms / positive contact (90%) or had a previous positive antigen test (36%). From all the seropositive cases only 44% were symptomatic. Our results show that seroprevalence of SARS -CoV-2 is high in the North, in parallel with the National Surveillance System. Seroprevalence was higher in woman than man and in adults older than 21. Almost all the people with symptoms or a positive contact had a positive test and were working at their regular places of work reflecting the danger of occupational exposure. Conclusions: These results suggest that, between January and March 2021, the restriction conditions were effective but unable to stop SARS-CoV-2 epidemic. It is essential to assess SARS-CoV-2 seroprevalence to monitor population immunity and if it lasts, specially from new COVID 19 variants
Infection of guava by Colletotrichum gloeosporioides and Colletotrichum acutatum under different temperatures and wetting periods
A antracnose, causada por Colletotrichum gloeosporioides e Colletotrichum acutatum, é uma das principais doenças pós-colheita em goiabas. Este trabalho teve por objetivo determinar a influência de fatores ambientais na germinação e na formação de apressórios de Colletotrichum gloeosporioides e C. acutatum e na infecção de goiabas 'Kumagai' por estes patógenos. A germinação e a formação de apressórios in vitro foram determinadas sob temperaturas de 10, 15, 20, 25, 30, 35 e 40ºC, com períodos de molhamento de 6, 12 e 24 horas. A infecção de goiabas foi determinada sob temperaturas de 15, 20, 25 e 30ºC e período de molhamento de 24 horas. Não houve germinação a 40ºC em nenhuma das duas espécies. A germinação e formação de apressórios foram bastante elevadas no intervalo de 15 a 30ºC para C. gloeosporioides, com máximo a 25ºC. Para a espécie C. acutatum, a germinação e a formação de apressórios foram mais sensíveis a variações da temperatura, com máximo a 20ºC. Os períodos de molhamento testados pouco influenciaram a germinação de C. gloeosporioides, enquanto que em C. acutatum a germinação foi significativamente menor com 6 horas de molhamento em relação a 12 e 24 horas. A infecção de goiabas, pelas duas espécies fúngicas, foi crescente com a temperatura, diferentemente da germinação de conídios e formação de apressórios. Incidências de 100% de frutos doentes ocorreram a 30ºC, para ambas as espécies, aos 10 dias após a inoculação.Anthracnose, caused by Colletotrichum gloeosporioides and C. acutatum, is one of the main post-harvest diseases in guavas. This study aimed to determine the influence of environmental variables on germination and appressorium formation of Colletotrichum gloeosporioides and C. acutatum and infection of "Kumagai" guavas by these pathogens. The germination rate and the apressorium formation rate in vitro were determined under temperatures of 10, 15, 20, 25, 30, 35 and 40ºC, with wetting periods of 6, 12 and 24 hours. The infection of guavas was determined under temperatures of 15, 20, 25 and 30ºC and wetting period of 24 hours. There was no germination at 40ºC for either species. The germination and apressorium formation rate were rather high in the range of 15 to 30ºC for C. gloeosporioides, with a maximum at 25ºC. For the species C. acutatum, germination and apressorium formation rates were more sensitive to variations in temperature, with a maximum at 20ºC. The wetting periods tested somewhat influenced the germination of C. gloeosporioides, whereas in C. acutatum the germination was significantly lower with 6 hours of wetting than 12 and 24 hours. The infection of guavas, for both fungal species, increased with the temperature, unlike conidium germination and apressorium formation. Incidences of 100% occurred with 30°C, at 10 days after the inoculation.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Fibrosing Alopecia in a Pattern Distribution: Pathogenesis, Diagnosis and Treatment
Fibrosing alopecia in a pattern distribution is a recently recognized type of scarring alopecia, with hair loss in androgens- dependent area. Loss of follicular openings, perifollicular erythema, perifollicular hyperkeratosis and anisotriquia are the trichoscopic clues and follicular lichenoid inflammatory infiltrate the important finding in histopathology. It shares features of androgenetic alopecia and lichen planopilaris. Dermatologists should be familiarized with this entity in order to optimize the diagnosis and provide early treatment to prevent irreversible follicular damage.Alopecia fibrosante em padrão de distribuição androgenética é uma forma clínica de alopecia cicatricial recentemente reconhecida, manifestando-se por rarefacção de cabelo na área dependente de androgénios. Ausência de orifícios foliculares, eritema e hiperqueratose peri-pilar, e anisotriquia são as pistas em tricoscopia e o infiltrado inflamatório liquenóide folicular achado importante em histopatologia. Partilha características de alopecia androgenética e líquen plano pilar. Os dermatologistas devem estar familiarizados com esta entidade, a fim de otimizar o diagnóstico e tratar precocemente, evitando dano folicular irreversível
Industrial wastewater treatment through bioaugmentation
Bioaugmentation of activated sludge processes through the addition of microorganisms is employed with the aim of enhancing treatment, in particular the removal of priority pollutants. With industrial wastewaters, studies have covered target pollutants including ammonia and polycyclic aromatic hydrocarbons (PAHs): compounds that are regulated around the globe. However, bioaugmentation is a technique that has been associated with doubt in regard to its ability to benefit treatment processes. Failure of bioaugmentation has been reported to be associated with numerous factors that include the growth rate being lower than the rate of washout, insufficient inoculum size and substrate availability. Limitations of bioaugmentation can be overcome through techniques that include increased inocula dosing, pre-acclimatisation of inocula in side-stream reactors, addition of nutrients and surfactants and application of sufficient acclimatisation periods. Surveys of the literature show that a key area for further research should be towards acquiring a better understanding of the degradation pathways where bioaugmentation is applied. There also remains a need to undertake bioaugmentation efficacy studies at full scale with test and control streams. Further reporting on the economic viability of the technique is also necessary
Nitrogen removal from coke making wastewater through a pre-denitrification activated sludge process
Under the Industrial Emissions Directive (IED), coke production wastewater must be treated to produce an effluent characterised by a total nitrogen (TN) 5.7 to produce an effluent TN 5.7 or, alternately, the addition of an external carbon source should be considered
Análise do impacto do relevo na ocupação do solo urbano em zonas de montanha – Aplicação à cidade da Guarda, Portugal
O relevo é um dos fatores que influenciam o crescimento urbano e a sua morfologia. Este elemento natural, dependendo da sua intensidade, pode condicionar o desenvolvimento urbano sustentável. A existência de barreiras topográficas obriga à fragmentação do tecido urbano e consequente dispersão. Apresenta-se ao longo deste artigo a metodologia desenvolvida com o objetivo de analisar a integração das classes de uso e ocupação do solo urbano na topografia urbana. A análise espacial desenvolveu-se com recurso a Sistemas de Informação Geográfica. Os resultados obtidos permitiram concluir acerca da integração dos vários tipos de uso e ocupação do solo urbano no declive local; avaliar a existência de barreiras topográficas naturais no interior de espaços urbanos construídos, constituindo elementos fraturantes do crescimento urbano; analisar a inclusão de usos e ocupações de solo artificializado em zonas de risco. Esta análise constitui uma ferramenta de apoio ao planeamento urbano, na identificação de zonas de risco
Urban sprawl assessment model in the context of sustainable development
The disordered urban growth may prove catastrophic for the future of cities if preventive measures are
not taken. The increase of built-up areas, the growing need for implementation of urban infrastructures, the
resulting increase in soil sealing, the excessive consumption of natural resources, the elevated need for car use
on daily travels, the increase in travel distances, etc., are examples of the negative effects caused by urban
sprawl. In order to implement measures to halt or avoid the damage caused by urban sprawl on the
environment, society and economy, it is necessary to know which areas to intervene. In this sense, a
multicriteria analysis model is presented that combines sustainable development indicators, with the main
objective of calculating an index of sustainable urban expansion. This model, developed according to the
Analytical Hierarchy Process, comprises three levels of analysis. At the first level, the indicators of urban
sustainable development are aggregated and associated withsix criteria. The weighted aggregate of composite
indicators, which constitute the second level of analysis, allows evaluating different scenarios and studying the
level of influence of urban sprawl on the diverse dimensions. In the last level of analysis, an index is
calculated,resulting from the aggregation of all indicatorsconsidered along the hierarchical structure. Thus, the
proposed model allows quantifying the level of sustainability of urban sprawl, according to the lines of
sustainable development defined for this work, serving as a tool to support urban planning interventions
Ciprofloxacin removal catalysed by conductive carbon materials
Current wastewater treatment technologies are not effective in the removal of pharmaceuticals. In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals. However, these reactions occur generally at a slow rate, due to electron transfer limitations, and might be accelerated through redox mediators (RM). Carbon nanomaterials (CM) have been effective RM in the biological reduction of other pollutants. For instance, CNT@2%Fe were found to increase 76-fold the biological reduction of Acid Orange 10. The magnetic properties of those composites allow their easier recover after the process by using a magnetic field. In this study, CNT and CNT@2%Fe were studied in the anaerobic removal of Ciprofloxacin (CIP). Furthermore, the potential contribution of adsorption and biodegradation processes for CIP removal was assessed.
Toxicity assessment is highly important as it is desired that the products formed after the process are not more toxic than the initial compound. Moreover, the evaluation of the possible contribution of nanomaterials used in the process for the final toxic effect of threated solution, is crucial. In this sense, the detoxification of the treated solutions was evaluated towards Vibrio fischeri.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 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
m5U54 tRNA hypomodification by lack of TRMT2A drives the generation of tRNA-derived small RNAs
Transfer RNA (tRNA) molecules contain various post-transcriptional modifications that are crucial for tRNA stability, translation efficiency, and fidelity. Besides their canonical roles in translation, tRNAs also originate tRNA-derived small RNAs (tsRNAs), a class of small non-coding RNAs with regulatory functions ranging from translation regulation to gene expression control and cellular stress response. Recent evidence indicates that tsRNAs are also modified, however, the impact of tRNA epitranscriptome deregulation on tsRNAs generation is only now beginning to be uncovered. The 5-methyluridine (m5U) modification at position 54 of cytosolic tRNAs is one of the most common and conserved tRNA modifications among species. The tRNA methyltransferase TRMT2A catalyzes this modification, but its biological role remains mostly unexplored. Here, we show that TRMT2A knockdown in human cells induces m5U54 tRNA hypomodification and tsRNA formation. More specifically, m5U54 hypomodification is followed by overexpression of the ribonuclease angiogenin (ANG) that cleaves tRNAs near the anticodon, resulting in accumulation of 5′tRNA-derived stress-induced RNAs (5′tiRNAs), namely 5′tiRNA-GlyGCC and 5′tiRNA-GluCTC, among others. Additionally, transcriptomic analysis confirms that down-regulation of TRMT2A and consequently m5U54 hypomodification impacts the cellular stress response and RNA stability, which is often correlated with tiRNA generation. Accordingly, exposure to oxidative stress conditions induces TRMT2A down-regulation and tiRNA formation in mammalian cells. These results establish a link between tRNA hypomethylation and ANG-dependent tsRNAs formation and unravel m5U54 as a tRNA cleavage protective mark.publishe
Enhancing the removal of pollutants from coke wastewater by bioaugmentation: a scoping study
BACKGROUND
Bioaugmentation and biostimulation were investigated for their ability to improve the removal of thiocyanate (SCN-), polycyclic aromatic hydrocarbons (PAHs), phenol and trace metals in coke wastewater. Additionally, the ability of the microorganisms supplemented with the bioaugmentation product to survive in a simulated river water discharge was evaluated.
RESULTS
A commercially available bioaugmentation product composed mainly of Bacillus sp. was mixed with activated sludge biomass. A dose of 0.5 g/L increased the removal of Ʃ6PAHs (sum of fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene) by 51% and reduced SCN- below 4 mg/L enabling compliance with the EU Industrial Emissions Directive (IED). Biostimulation (supplementing micronutrients and alkalinity) allowed compliance for both SCN- and phenol (<0.5 mg/L).
Bacillus sp. accounted for 4.4% of the microbial population after 25 hours (1.5 g/L dose) which declined to 0.06% after exposure to river water (24 hours). Exposure of the activated sludge biomass to river water resulted in a 98.6% decline in viable cell counts.
CONCLUSION
To comply with the IED, bioaugmentation and biostimulation are recommended for the treatment of coke wastewater to enable an effluent Ʃ6PAHs of 6.6 μg/L, 0.3 mg/L phenol and 1.2 mg/L SCN-. Such techniques are not anticipated to impact on downstream river water quality
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