Ecotoxicological Assessment of "Glitter" Leachates in Aquatic Ecosystems: An Integrated Approach

The most worrisome fraction within plastic pollution is that of microplastics (MP). A category of MP almost completely ignored is that of glitter. The objective of this study is to test the toxicity of nine types of glitter leachate (3 soak times: 3, 90 and 180 days) on model organisms in freshwater (Allivibrio fischeri, Raphidocelis subcapitata, Daphnia magna) and saltwater (Allivibrio fischeri, Phaeodactylum tricornutum, Paracentrotus lividus). An integrated approach was applied to obtain the percentage of ecotoxicological risk. The results show that (i) photosynthesizing primary producers are the most sensitive trophic level; (ii) algae transitioned from growth inhibition to biostimulation; (iii) D. magna showed higher sensitivity after 48 h compared to 24 h; (iv) A. fischeri responded more strongly in saltwater than in freshwater. The integrated data show a greater risk associated with the marine environment, with the highest risk for glitters that are hexagonal and composed of poly-methyl-methacrylate. Our multivariate analysis shows that the toxicity of plastic leaching is a complex phenomenon that depends on the sensitivity of the species, in some cases on the soaking time and on the medium, and is not clearly linked to the polymer type, the contact area or the colors of the particles

Ecotoxicity of marine sediments: Sampling and laboratory artifacts and their impacts on risk classification

Assessing the ecotoxicological risk of marine sediments is now a critical factor in deciding how to treat dredged material in harbor and coastal areas. Although ecotoxicological analyses are routinely required by some regu-latory agencies in Europe, laboratory skills necessary to perform them are often underestimated. According to the Italian Ministerial decree No. 173/2016, ecotoxicological tests are performed on the solid phase and elutriates, and the classification of sediment quality is defined using the "Weight of Evidence" (WOE) approach. However, the decree does not provide adequate information regarding the preparation techniques and laboratory skills. As result, a wide variability among laboratories occurs. An error in the classification of ecotoxicological risk has a negative impact on the whole environmental quality and/or the economy and management of the interested area. Thus, the main aim of this study was to determine if such variability can affect the ecotoxicological out-comes of tested species and WOE associated classification, producing different options for the management of dredged sediments. Four different sediment types were selected to assess the ecotoxicological responses and their changes as a function of variability of the following factors: a) the storage time laps (STL) for both the solid phase and the elutriates; b) the methods used to prepare the elutriates (centrifugation vs. filtration), and the conser-vation method used for the elutriates (freshly prepared vs. freezing). Results suggest a wide variability of eco-toxicological responses among the four sediment samples here considered, differentiated according to chemical pollution, grain-size texture, and macronutrient contents. The storage time laps significantly affect the physi-cochemical parameters and the ecotoxicity of both the solid phase test and elutriates. For the elutriates prepa-ration, centrifugation is preferred to filtration to preserve a better representation of sediment heterogeneity. Freezing of elutriates does not seem to show any significant effects on the toxicity. Findings allow to define a weighted schedule of the storage time of sediments and elutriates useful for laboratories to scale analytical priority and strategies related to different sediment types

RNA structure framework: automated transcriptome-wide reconstruction of RNA secondary structures from high-throughput structure probing data

Abstract Summary: The rapidly increasing number of discovered non-coding RNAs makes the understanding of their structure a key feature toward a deeper comprehension of gene expression regulation. Various enzymatic- and chemically- based approaches have been recently developed to allow whole-genome studies of RNA secondary structures. Several methods have been recently presented that allow high-throughput RNA structure probing (CIRS-seq, Structure-seq, SHAPE-seq, PARS, etc.) and unbiased structural inference of residues within RNAs in their native conformation. We here present an analysis toolkit, named RNA Structure Framework (RSF), which allows fast and fully-automated analysis of high-throughput structure probing data, from data pre-processing to whole-transcriptome RNA structure inference. Availability and implementation: RSF is written in Perl and is freely available under the GPLv3 license from http://rsf.hugef-research.org. Contact:  [email protected] Supplementary information:  Supplementary data are available at Bioinformatics online.</jats:p

Weekend mortality in an Italian hospital: immediate versus delayed bedside critical care treatment

Background: a number of studies highlighted increased mortality associated with hospital admissions during weekends and holidays, the so-call "weekend effect". In this retrospective study of mortality in an acute care public hospital in Italy between 2009 and 2015, we compared inpatient mortality before and after a major organizational change in 2012. The new model (Model 2) implied that the intensivist was available on call from outside the hospital during nighttime, weekends, and holidays. The previous model (Model 1) ensured the presence of the intensivist coordinating a Medical Emergency Team (MET) inside the hospital 24 h a day, 7 days a week. Methods: life status at discharge after 9298 and 8223 hospital admissions that occurred during two consecutive periods of 1185 days each (organizational Model 1 and 2), respectively, were classified into "discharged alive", "deceased during nighttime-weekends-holidays" and "deceased during daytime-weekdays". We estimated Relative Risk Ratios (RRR) for the associations between the organizational model and life status at discharge using multinomial logistic regression models adjusted for demographic and case-mix indicators, and timing of admission (nighttime-weekends-holidays vs. daytime-weekdays). Results: there were 802 and 840 deaths under Models 1 and 2, respectively. Total mortality was higher for hospital admissions under Model 2 compared to Model 1. Model 2 was associated with a significantly higher risk of death during nighttime-weekends-holidays (IRR: 1.38, 95% CI 1.20-1.59) compared to daytime-weekdays (RRR: 1.12, 95% CI 0.97-1.31) (p = 0.04). Respiratory diagnoses, in particular, acute and chronic respiratory failure (ICD 9 codes 510-519) were the leading causes of the mortality excess under Model 2. Conclusions: our data suggest that the immediate availability of an intensivist coordinating a MET 24 h, 7 days a week can result in a better prognosis of in-hospital emergencies compared to delayed consultation

The First Evidence of the Water Bioremediation Potential of Ficopomatus enigmaticus (Fauvel 1923): From Threat to Resource?

Each year, a staggering 700,000 tons of synthetic dyes are manufactured globally, leading to the release of dye-laden wastewater into aquatic systems. These synthetic dyes resist biodegradation, endangering human and environmental health. Since traditional wastewater treatments are basically unable to remove dyes, exploring the potential of alternative solutions, such as bioremediation, is crucial to reduce dye contamination in aquatic ecosystems. Ficopomatus enigmaticus (Fauvel 1923), listed as one of the 100 worst invasive species in Europe, is considered an invasive ecosystem engineer capable of causing economic and ecological losses. Despite this negative status, the literature suggests its positive contributions to aquatic ecosystems as habitat former and water bioremediator. However, existing evidence on the potential of F. enigmaticus to improve water quality is fragmented and lacks experimental data from laboratory tests. This study examined the potential of Ficopomatus reefs, both living and dead, to enhance water quality by removing contaminants, focusing on methylene blue (MB), one of the most common synthetic dyes. Bioaccumulation and bioadsorption were identified as key mechanisms for dye removal, supported by ATR-FTIR and microscopic analyses. Ficopomatus efficiently removed up to 80% of MB within 24 h. Bioaccumulation in the soft body accounted for 18% of the total removal, while complex adsorption phenomena involving carbonaceous, microalgal, and organic reef components accounted for 82%. Surprisingly, bioremediated solutions exhibited significant effects in ecotoxicological tests on bacteria, indicating the potential of F. enigmaticus to disrupt bacterial quorum sensing related to biofilm formation, and suggesting a possible antifouling action. This study underscores the intricate interplay between F. enigmaticus, water quality improvement, and potential ecological consequences, stressing the need for further investigation into its multifaceted role in aquatic ecosystems

Data symmetries and Learning in fully connected neural networks

Symmetries in the data and how they constrain the learned weights of modern deep networks is still an open problem. In this work we study the simple case of fully connected shallow non-linear neural networks and consider two types of symmetries: full dataset symmetries where the dataset X is mapped into itself by any transformation g , i.e. gX = X or single data point symmetries where gx = x , x ∈ X . We prove and experimentally confirm that symmetries in the data are directly inherited at the level of the network’s learned weights and relate these findings with the common practice of data augmentation in modern machine learning. Finally, we show how symmetry constraints have a profound impact on the spectrum of the learned weights, an aspect of the so-called network implicit bias

Navigating a Microplastic Sea: How the Pacific Cupped Oyster (Magallana gigas) Respond to Microplastic Pollution in Lagoons

Microplastic pollution poses an escalating concern, particularly in coastal lagoons rich in biodiversity. This study delved into the occurrence of microplastics (MPs) in Magallana gigas (formerly Crassostrea gigas) from the Orbetello and Varano coastal lagoons (Italy), also investigating the response of these filter-feeding organisms to various colors (P = pink; B = blue; W = white) of high-density polyethylene (HDPE) MP fragments. Oysters were exposed for 7 days under controlled conditions. Subsequently, the oysters underwent analysis for both MP presence and biochemical markers of oxidative stress. Diverse ingestion rates of HDPE were noted among oysters from the two lagoons, eliciting antioxidant responses and modifying baseline activity. The two-way ANOVA revealed the significant effects of treatment (control; HDPE_B; HDPE_P; HDPE_W), site, and the interaction between treatment and site on all biomarkers. Non-metric multidimensional scaling showed a divergent effect of HDPE color on biomarkers. Further investigation is warranted to elucidate the mechanisms underlying the influence of MP color, dose-dependent effects, and the long-term impacts of exposure. Comprehending these intricacies is imperative for devising effective strategies to mitigate plastic pollution and safeguard marine health

Genome-scale deconvolution of RNA structure ensembles

RNA structure heterogeneity is a major challenge when querying RNA structures with chemical probing. We introduce DRACO, an algorithm for the deconvolution of coexisting RNA conformations from mutational profiling experiments. Analysis of the SARS-CoV-2 genome using dimethyl sulfate mutational profiling with sequencing (DMS-MaPseq) and DRACO, identifies multiple regions that fold into two mutually exclusive conformations, including a conserved structural switch in the 3' untranslated region. This work may open the way to dissecting the heterogeneity of the RNA structurome