Microplastics are persistent contaminants accumulating in the environment. Aquatic ecosystems have been studied worldwide, revealing ubiquitous contamination with microplastics. Microalgae, one of ...the most important primary producers in aquatic ecosystems, could suffer from microplastic contamination, leading to larger impacts on aquatic food webs. Nonetheless, little is known about the toxic effects of microplastics on microalgae populations. Thus, the objective of this review was to identify these effects and the impacts of microplastics on microalgae populations based on currently available literature, also identifying knowledge gaps. Even though microplastics seem to have limited effects on parameters such as growth, chlorophyll content, photosynthesis activity and reactive oxygen species (ROS), current environmental concentrations are not expected to induce toxicity. Even so, microplastics could disrupt population regulation mechanisms, by reducing the availability or absorption of nutrients (bottom-up) or reducing the population of predator species (top-down). Microplastics' properties can also influence the effects on microalgae, with smaller sizes and positive surface charges having higher toxicity. Therefore, more research is needed to better understand the effects of microplastics on microalgae, such as adaptation strategies, effects on population dynamics and microplastics properties influencing toxicity.
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•Microplastics' current concentrations are not expected to directly harm microalgae.•Microplastics may inhibit predation or reduce nutrient availability in microalgae.•Factors responsible for species sensitivity and microplastics toxicity are unclear.
Calcium-dependent protein kinases (CDPKs) are encoded by a large gene family and play important roles against biotic and abiotic stresses and in plant growth and development. To date, little is known ...about the CDPK genes in strawberry (Fragaria x ananassa). In this study, analysis of Fragaria x ananassa CDPK gene family was performed, including gene structures, phylogeny, interactome and expression profiles. Nine new CDPK genes in Fragaria x ananassa were identified based on RNA-seq data. These identified strawberry FaCDPK genes were classified into four main groups, based on the phylogenetic analysis and structural features. FaCDPK genes were differentially expressed during fruit development and ripening, as well as in response to abiotic stress (salt and drought), and hormone (abscisic acid) treatment. In addition, the interaction network analysis pointed out proteins involved in the ABA-dependent response to plant stress via Ca
signaling, especially RBOHs. To our knowledge, this is the first report on CDPK families in Fragaria x ananassa, and it will provide valuable information for development of biofortified fruits and stress tolerant plants.
The largest monkeypox virus (MPXV) outbreak described so far in non-endemic countries was identified in May 2022 (refs.
). In this study, shotgun metagenomics allowed the rapid reconstruction and ...phylogenomic characterization of the first MPXV outbreak genome sequences, showing that this MPXV belongs to clade 3 and that the outbreak most likely has a single origin. Although 2022 MPXV (lineage B.1) clustered with 2018-2019 cases linked to an endemic country, it segregates in a divergent phylogenetic branch, likely reflecting continuous accelerated evolution. An in-depth mutational analysis suggests the action of host APOBEC3 in viral evolution as well as signs of potential MPXV human adaptation in ongoing microevolution. Our findings also indicate that genome sequencing may provide resolution to track the spread and transmission of this presumably slow-evolving double-stranded DNA virus.
The use of pesticides for crop protection may result in the presence of toxic residues in environmental matrices. In the aquatic environment, pesticides might freely dissolve in the water or bind to ...suspended matter and to the sediments, and might be transferred to the organisms' tissues during bioaccumulation processes, resulting in adverse consequences to non-target species. One such group of synthetic organic pesticides widely used worldwide to combat pathogenic fungi affecting plants is the strobilurin chemical group. Whereas they are designed to control fungal pathogens, their general modes of action are not specific to fungi. Consequently, they can be potentially toxic to a wide range of non-target organisms. The present work had the intent to conduct an extensive literature review to find relevant research on the occurrence, fate and effects of azoxystrobin, the first patent of the strobilurin compounds, in aquatic ecosystems in order to identify strengths and gaps in the scientific database. Analytical procedures and existing legislation and regulations were also assessed. Data gathered in the present review revealed that analytical reference standards for the most relevant environmental metabolites of azoxystrobin are needed. Validated confirmatory methods for complex matrices, like sediment and aquatic organisms' tissues, are very limited. Important knowledge of base-line values of azoxystrobin and its metabolites in natural tropical and estuarine/marine ecosystems is lacking. Moreover, some environmental concentrations of azoxystrobin found in the present review are above the Regulatory Acceptable Concentration (RAC) in what concerns risk to aquatic invertebrates and the No Observed Ecologically Adverse Effect Concentration (NOEAEC) reported for freshwater communities. The present review also showed that there are very few data on azoxystrobin toxicity to different aquatic organisms, especially in what concerns estuarine/marine organisms. Besides, toxicity studies mostly address azoxystrobin and usually neglect the more relevant environmental metabolites. Further work is also required in what concerns effects of exposure to multi-stressors, e.g. pesticide mixtures. Even though Log Kow for azoxystrobin and R234886, the main metabolite of azoxystrobin in water, are below 3, the bio-concentration factor and the bioaccumulation potential for azoxystrobin are absent in the literature. Moreover, no single study on bioaccumulation and biomagnification processes was found in the present review.
Natural organic matter may confound the detection of microplastics, requiring a removal step. However, most available protocols are long and lack information on removal efficiency and polymer ...degradation. Thus, we have determined the digestion efficiency (%) for a pool of organic matter (algae, driftwood, feathers, fish muscle, paraffin, palm oil) for five digestion solutions, hydrogen peroxide (H2O2), hydrogen peroxide with iron catalyst (H2O2 + Fe), potassium hydroxide (KOH), nitric acid (HNO3), and sodium dodecyl sulphate (SDS), under two temperatures (room temperature at 25 °C, 50 °C) and two periods (1, 6 h). H2O2 + Fe and KOH at 50 °C for 1 h had the highest digestion efficiencies, of 65.9% and 58.3% respectively (mostly limited by driftwood and paraffin). Further testing revealed that H2O2 + Fe is more appropriate for plant material and KOH for animal tissue. Weight loss (%), Fourier transform infrared spectrometry and carbonyl index of 9 virgin and 6 weathered polymers (polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, cellulose acetate, nylon) revealed that only identification of cellulose acetate was hindered. Filters were also tested revealing that quartz and glass fibre filters are resistant to these protocols. Thus, a digestion protocol based on H2O2 + Fe or KOH at 50 °C for 1 h may be used on microplastic samples.
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•Highest digestion efficiencies were found for H2O2 + Fe and KOH at 50 °C for 1 h.•H2O2 + Fe is appropriate for removal of plant material and KOH for animal tissues.•Virgin and weathered plastics were not damaged, except for cellulose acetate.•Carbonyl index were slightly altered, but infrared spectra allowed identification.
A small number of individuals infected within a community can lead to the rapid spread of the disease throughout that community, leading to an epidemic outbreak. This is even more true for highly ...contagious diseases such as COVID-19, known to be caused by the new coronavirus SARS-CoV-2. Mathematical models of epidemics allow estimating several impacts on the population and, therefore, are of great use for the definition of public health policies. Some of these measures include the isolation of the infected (also known as quarantine), and the vaccination of the susceptible. In a possible scenario in which a vaccine is available, but with limited access, it is necessary to quantify the levels of vaccination to be applied, taking into account the continued application of preventive measures. This work concerns the simulation of the spread of the COVID-19 disease in a community by applying the Monte Carlo method to a Susceptible-Exposed-Infective-Recovered (SEIR) stochastic epidemic model. To handle the computational effort involved, a simple parallelization approach was adopted and deployed in a small HPC cluster. The developed computational method allows to realistically simulate the spread of COVID-19 in a medium-sized community and to study the effect of preventive measures such as quarantine and vaccination. The results show that an effective combination of vaccination with quarantine can prevent the appearance of major epidemic outbreaks, even if the critical vaccination coverage is not reached.
Up to 27 May 2022, Portugal has detected 96 confirmed cases of monkeypox. We describe 27 confirmed cases (median age: 33 years (range: 22-51); all males), with an earliest symptom onset date of 29 ...April. Almost all cases (n = 25) live in the Lisbon and Tagus Valley health region. Most cases were neither part of identified transmission chains, nor linked to travel or had contact with symptomatic persons or with animals, suggesting the possible previously undetected spread of monkeypox.
When Reading Mediation becomes Censorship Lopes Coelho, Isabel
The Lion and the unicorn (Brooklyn),
2022, 2022-01-00, 20220101, Volume:
46, Issue:
1
Journal Article
Peer reviewed
The young reader is not associated with the modern world in which s/he lives, but with an image of life 'from another time,' that is patriarchal and has no machinery, which reinforces the myth of ...happy past times, of a golden age." ...most of the texts chosen for compulsory reading in schools present to the contemporary reader not the society in which s/he lives, but the idyllic society "of once upon a time," of distant times, much closer to the purity of a world not yet influenced by industrial revolutions, in which the family ruled by the figure of the father becomes the model of life in society. ...the boy describes his mother's dress, after which the book is titled. The author chose the dress precisely to displace consolidated concepts about reality. ...wearing the dress does not imply a change in gender or sexual role, but rather, provokes a reflection about valuing special moments. In a light-hearted way, we enter into the private universe of Alexandra, who some days "wants to wear dresses and let her hair down" and other days "wants to wear shorts and a ponytail to play freely."
Pollution of the environment with plastic is an important concern of the modern world. It is estimated that annually over 350 million tonnes of this material are produced, wherein, despite the ...recycling methods, a significant part is deposited in the environment. The plastic has been detected in the industrial areas, as well as farmlands and gardens in many world regions. Larger plastic pieces degraded in time into smaller pieces including microplastic (MP) and nanoplastic particles (NP). Nanoplastic is suggested to pose the most serious danger as due to the small size, it is effectively taken up from the environment by the biota and transported within the organisms. An increasing number of reports show that NP exert toxic effects also on plants. One of the most common plant response to abiotic stress factors is the accumulation of reactive oxygen species (ROS). On the one hand, these molecules are engaged in cellular signalling and regulation of genes expression. On the other hand, ROS in excess lead to oxidation and damage of various cellular compounds. This article reviews the impact of NP on plants, with special emphasis on the oxidative response.
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