146 research outputs found

    Quantification and characterization of additives, plasticizers, and small microplastics (5-100 μm) in highway stormwater runoff

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    Highway stormwater (HSW) runoff is a significant pathway for transferring microplastics from land-based sources to the other surrounding environmental compartments. Small microplastics (SMPs, 5-100 μm), additives, plasticizers, natural, and nonplastic synthetic fibers, together with other components of micro-litter (APFs), were assessed in HSW samples via Micro-FTIR; oleo-extraction and purification procedures previously developed were optimized to accomplish this goal. The distribution of SMPs and APFs observed in distinct HSW runoff varied significantly since rainfall events may play a crucial role in the concentration and distribution of these pollutants. The SMPs' abundance varied from 11932 ± 151 to 18966 ± 191 SMPs/L. The dominating polymers were vinyl ester (VE), polyamide 6 (PA6), fluorocarbon, and polyester (PES). The APFs' concentrations ranged from 12825 ± 157 to 96425 ± 430 APFs/L. Most APFs originated from vehicle and tire wear (e.g., Dioctyl adipate or 5-Methyl-1H-benzotriazole). Other sources of these pollutants might be pipes, highway signs, packaging from garbage debris, road marking paints, atmospheric deposition, and other inputs. Assessing SMPs in HSW runoff can help evaluating the potential threat they may represent to receiving water bodies and air compartments. Besides, APFs in HSW runoff may be efficient proxies of macro- and microplastic pollution

    Finite element modeling of residual stress and geometrical error formations in selective laser melting of metals

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    Recent works, both numerical and experimental, on residual stress and geometrical errors in selective laser melting-produced parts highlighted the preponderance of these phenomena. However, their mechanisms of appearance are not yet fully explained. An in-house finite element model was developed and implemented to reproduce their formations. The consistence of the model with existing simulation results and with respect to experimental observations was checked. Simulations were then performed using a computational design of experiments to better comprehend the underlying phenomena and the influence of the laser speed and power. Relationships between process parameters and residual stress, plastic strain, and geometrical errors formations have been put into evidence which can support optimization procedures at design stage

    The use of Unmanned Aerial Vehicles (UAVs) to sample the blow microbiome of small cetaceans

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    Recent studies describe the use of UAVs in collecting blow samples from large whales to analyze the microbial and viral community in exhaled air. Unfortunately, attempts to collect blow from small cetaceans have not been successful due to their swimming and diving behavior. In order to overcome these limitations, in this study we investigated the application of a specific sampling tool attached to a UAV to analyze the blow from small cetaceans and their respiratory microbiome. Preliminary trials to set up the sampling tool were conducted on a group of 6 bottlenose dolphins (Tursiops truncatus) under human care, housed at Acquario di Genova, with approximately 1 meter distance between the blowing animal and the tool to obtain suitable samples. The same sampling kit, suspended via a 2 meter rope assembled on a waterproof UAV, flying 3 meters above the animals, was used to sample the blows of 5 wild bottlenose dolphins in the Gulf of Ambracia (Greece) and a sperm whale (Physeter macrocephalus) in the southern Tyrrhenian Sea (Italy), to investigate whether this experimental assembly also works for large whale sampling. In order to distinguish between blow-associated microbes and seawater microbes, we pooled 5 seawater samples from the same area where blow samples\u2019 collection were carried out. The the respiratory microbiota was assessed by using the V3-V4 region of the 16S rRNA gene via Illumina Amplicon Sequencing. The pooled water samples contained more bacterial taxa than the blow samples of both wild animals and the sequenced dolphin maintained under human care. The composition of the bacterial community differed between the water samples and between the blow samples of wild cetaceans and that under human care, but these differences may have been mediated by different microbial communities between seawater and aquarium water. The sperm whale\u2019s respiratory microbiome was more similar to the results obtained from wild bottlenose dolphins. Although the number of samples used in this study was limited and sampling and analyses were impaired by several limitations, the results are rather encouraging, as shown by the evident microbial differences between seawater and blow samples, confirmed also by the meta-analysis carried out comparing our results with those obtained in previous studies. Collecting exhaled air from small cetaceans using drones is a challenging process, both logistically and technically. The success in obtaining samples from small cetacean blow in this study in comparison to previous studies is likely due to the distance the sampling kit is suspended from the drone, which reduced the likelihood that the turbulence of the drone propeller interfered with successfully sampling blow, suggested as a factor leading to poor success in previous studies

    Cambios estructurales cerebrales en epilepsia generalizada idiopática identificados por análisis de imágenes de resonancia magnética automatizados.

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    Cerebral structural changes in generalized idiopathic epilepsy identified by automated magnetic resonance imaging analysis. The purpose of this study was to combine two automated methods of magnetic resonance imaging (MRI) structural analysis in order to identify structural changes in patients born in Argentina with idiopathic generalized epilepsy (IGE) compared to a healthy adult control group. Twenty-eight patients with IGE and 26 controls with no significant demographic differences were included. The analysis ofthe brain structures was conducted with two automated methods of magnetic resonance image analysis: voxelbased morphometry and FSL-integrated registration and segmentation toolbox (FSL-FIRST). FSL showed volume decrease in both thalamus in patients with IGE compared to the control group (left: 8092 mm3 control group vs. 7424 mm3 IGE, p = 0.0015; right: 7951 mm3 control group vs. 7247 mm3 IGE, p = 0.0016). A reduction in thevolume of both caudate nuclei was also seen (left: 3612 mm3 control group vs. 3376 mm3 IGE, p = 0.01; right: 3683 mm3 control group vs. 3459 mm3 IGE, p = 0.04). Voxel-based-morphometry showed a volume decrease in both caudate nuclei in patients with IGE compared to the control group. The other cerebral structures analyzed did not show significant differences between the groups. In conclusion, this study shows the reduction in volume in the subcortical, thalamic, and caudate nuclei structures in patients with IGE in comparison to control group.This study conducted in our country delves into the analysis of brain structural changes in patients with EGI compared to healthy subjects.Fil: Avalos, Juan Carlos. Hospital Italiano; ArgentinaFil: Sánchez, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Hospital Italiano; ArgentinaFil: Rosso, Barbara. Hospital Italiano; ArgentinaFil: Besocke, Ana Gabriela. Hospital Italiano; ArgentinaFil: García, María del Carmen. Hospital Italiano; Argentin

    MBOAT7 rs641738 increases risk of liver inflammation and transition to fibrosis in chronic hepatitis C

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    Cirrhosis likely shares common pathophysiological pathways despite arising from a variety of liver diseases. A recent GWAS identified rs641738, a polymorphism in the MBOAT7 locus, as being associated with the development of alcoholic cirrhosis. Here we explore the role of this variant on liver inflammation and fibrosis in two cohorts of patients with chronic hepatitis C. In 2,051 patients, rs641738 associated with severe hepatic inflammation and increased risk of fibrosis, as well as fast fibrosis progression. At functional level, rs641738 associated with MBOAT7 transcript and protein levels in liver and blood, and with serum inflammatory, oxidative stress and macrophage activation markers. MBOAT7 was expressed in immune cell subsets, implying a role in hepatic inflammation. We conclude that the MBOAT7 rs641738 polymorphism is a novel risk variant for liver inflammation in hepatitis C, and thereby for liver fibrosis
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