Motionless of snail Hydrobia ulvae (Pennant) as response to sediment toxicity and its consequences for the post-exposure feeding

Post-exposure feeding and motionless may be useful endpoints for assessing toxicity. The present study aimed to examine (i) the immobility of the estuarine snail Hydrobia ulvae resulting from short-term exposure to copper-spiked sediment, and subsequently, (ii) the potential application of post-exposure feeding (indirectly measured as pellets excreted) as an ecotoxicological response associated with motionlessness. Mobility and post-exposure feeding were influenced by copper contamination. Motionless was noticeable above the concentration of 200 μg Cu g-1, where 40% of the organisms were inactive. Practically all the organisms remained active at the two lowest concentrations: 40 (control) and 60 μg Cu g-1. For 400 and 800 μg Cu g-1 the motionless was generally higher than 50%. Mortality higher than 25% was observed at 200, 400 and 800 μg Cu g-1, with values of 27, 40 and 60%, respectively. The feeding inhibition values showed an increasing inhibition from 20% at the lowest concentration (60 μg Cu g-1), up to 59% at 400 μg Cu g-1; at concentration of 800 μg Cu g-1, although the physical activity inhibition had reached 67%, the post-exposure feeding was 1.5 higher in relation to the control. Probably, the starvation period due to motionless during exposure seems to increase the post-exposure feeding and egestion when food was provided; alternatively, increased pellet production could also indicate a detoxification process

UV-LEDs combined with persulfate salts as a method to inactivate microalgae in ballast water

The Ballast Water Management Convention (BWMC) establishes limits for viable organisms in discharged ballast water. UV-based ballast water management systems (BMWS) are among the most common, especially those with low pressure (LP) and medium pressure (MP) mercury lamps. An interesting alternative to mercury lamps could be UV LEDs that have been developing over recent years. UVA, UVB, and UVC LEDs have been tested as a method to inactivate microalgae in ballast water. For this study, the diatom Phaeodactylum tricornutum was selected as a target organism. Comparing the D2 (dose required to achieve two log reductions) for P. tricornutum from different UV treatments, it was observed that UVC LEDs were 74.2 % more efficient than UVB LEDs and, compared with previous studies, 48.1 % more efficient than UVC LP mercury lamps. If a five day dark post-treatment was combined with the UV irradiation to avoid photoreactivation, UVC LEDs were 90 % more efficient than UVB LEDs and, compared with previous studies, 36.8 % more efficient than UVC LP mercury lamps. No damage with or without photoreactivation was caused by UVA irradiation with doses up to 4·104 mJ cm−2. The combination of peroxymonosulfate (PMS) with UVA, UVB and UVC LEDs did not significantly increase the inactivation, and the combination of the peroxydisulfate (PDS) with UVC LEDs slightly decreases the inactivation compared with UVC irradiation alone. In conclusion, UVC LEDs were the most efficient for inactivating P. tricornutum, and the combination of PMS and PDS with UV LEDs did not notably improve it. © 2022 The Author

Acumulación de Cu y Zn por célular microalgales marinas de Nannochloropsis gaditana (Eustigmatophyceae) inmovilizadas en alginato de calcio

13 páginas, 5 figuras, 2 tablas.[EN] Different experiments about the accumulation capacity for copper and zinc were carried out on the marine microalgae Nannochloropsis gaditana Lubián (Eustigmatophyceae). A 24-hour study of the evolution of accumulated metal in the beads revealed two possible accumulation phases. Accumulation differences between free and immobilized microalgal cells were investigated finding no differences for copper, and little differences for zinc. Free cells accumulated practically 100% Cu or Zn in the media under experimental conditions. Experiments in order to compare the accumulation capacity of living vs. dead cells were designed too, obtaining the largest accumulation levels for both metals in the beads containing immobilized living microalgae. In experiments carried out in continuous-flow reactors, beads with entrapped cells showed to be more efficient removing Cu and Zn than beads without cells. In all the experiments, the calcium alginate beads showed strong affinity for Cu. Similar results were obtained when accumulation by packed beads in columns was tested, but efficacy was higher if this design was used (beads with cells retain 80% of Cu introduced in the column).[ES] Se han realizado distintos experimentos sobre la capacidad de acumulación de cobre y zinc por parte de la microalga marina Nannochloropsis gaditana Lubián (Eustigmatophyceae). Un estudio de la evolución del metal acumulado durante 24 horas reveló la existencia de dos posibles fases de acumulación. Se investigaron las diferentes capacidades de acumulación de células microalgales libres e inmovilizadas, no encontrándose diferencias para el cobre y pequeñas diferencias para el zinc. Las células libres acumularon prácticamente el 100% del Cu o Zn presentes en el medio, en las condiciones experimentales. Se desarrollaron experimentos encaminados a determinar la capacidad de acumulación de estos metales por parte de algas inmovilizadas vivas frente a la de algas inmovilizadas muertas, encontrándose los niveles acumulativos más altos para ambos metales en las gotas de alginato que contenían algas vivas. En experimentos realizados en reactores de flujo continuo, las gotas de alginato con células inmovilizadas en su interior demostraron ser más eficientes en cuanto a la retirada de Cu y Zn del medio que las gotas sin algas. En todos los experimentos realizados se observa una fuerte afinidad del Cu por el alginato de calcio. Se obtuvieron resultados similares cuando se ensayó la acumulación de metales en gotas de alginato dispuestas en columnas llenas, aunque la eficacia fue mayor cuando se usó este último diseño (las gotas de alginato con células retuvieron el 80% del Cu introducido en la columna).Peer reviewe

Evaluation of algaecide effectiveness of five different oxidants applied on harmful phytoplankton

Harmful algal blooms (HABs) in coastal areas similarly impact both ecosystems and human health. The translocation of phytoplankton species via maritime transport can potentially promote the growth of HABs in coastal systems. Accordingly, ballast water must be disinfected. The main goal of this study is to assess the effectiveness of different emerging biocides, including H2O2, peracetic acid (PAA), peroxymonosulfate (PMS), and peroxydisulfate (PDS). The effectiveness of these biocides is compared with that of conventional chlorination methods. Their effects on two ichthyotoxic microalgae with worldwide distribution, i.e., Prymnesium parvum and Heterosigma akashiwo, are examined. To ensure the prolonged effectiveness of the different reagents, their concentration–response curves for 14 days are constructed and examined. The results suggest a strong but shorter effect by PMS (EC50 = 0.40–1.99 mg·L-1) and PAA (EC50 = 0.32–2.70 mg·L-1), a maintained effect by H2O2 (EC50 = 6.67–7.08 mg·L-1), and a negligible effect by PDS. H. akashiwo indicates higher resistance than P. parvum, except when H2O2 is used. Based on the growth inhibition performance and consumption of the reagents as well as a review of important aspects regarding their application, using H2O2, PAA, or PMS can be a feasible alternative to chlorine-based reagents for inhibiting the growth of harmful phytoplankton.This work has been co-funded by the 2014–2020 ERDF Operational Programme and by the Department of Economy, Knowledge, Business and University of the Regional Government of Andalusia (Spain). Project Ref.: FEDER-UCA18–108023. This work is part of the project TED2021–130994B-C31; TED2021–130994B-C33 and Grant IJC2020–042741-I funded by MCIN/AEI/10.13039/501100011033 and by the European Union NextGenerationEU/PRTR

Multi-LiDAR Mapping for Scene Segmentation in Indoor Environments for Mobile Robots

Nowadays, most mobile robot applications use two-dimensional LiDAR for indoor mapping, navigation, and low-level scene segmentation. However, single data type maps are not enough in a six degree of freedom world. Multi-LiDAR sensor fusion increments the capability of robots to map on different levels the surrounding environment. It exploits the benefits of several data types, counteracting the cons of each of the sensors. This research introduces several techniques to achieve mapping and navigation through indoor environments. First, a scan matching algorithm based on ICP with distance threshold association counter is used as a multi-objective-like fitness function. Then, with Harmony Search, results are optimized without any previous initial guess or odometry. A global map is then built during SLAM, reducing the accumulated error and demonstrating better results than solo odometry LiDAR matching. As a novelty, both algorithms are implemented in 2D and 3D mapping, overlapping the resulting maps to fuse geometrical information at different heights. Finally, a room segmentation procedure is proposed by analyzing this information, avoiding occlusions that appear in 2D maps, and proving the benefits by implementing a door recognition system. Experiments are conducted in both simulated and real scenarios, proving the performance of the proposed algorithms.This work was supported by the funding from HEROITEA: Heterogeneous Intelligent Multi-Robot Team for Assistance of Elderly People (RTI2018-095599-B-C21), funded by Spanish Ministerio de Economia y Competitividad, RoboCity2030-DIH-CM, Madrid Robotics Digital Innovation Hub, S2018/NMT-4331, funded by “Programas de Actividades I+D en la Comunidad de Madrid” and cofunded by Structural Funds of the EU. We acknowledge the R&D&I project PLEC2021-007819 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union NextGenerationEU/PRTR and the Comunidad de Madrid (Spain) under the multiannual agreement with Universidad Carlos III de Madrid (“Excelencia para el Profesorado Universitario’—EPUC3M18) part of the fifth regional research plan 2016–2020

Improving the WFD purposes by the incorporation of ecotoxicity tests

Trabajo presentado en la 4th SCARCE International Conference (Towards a better understanding of the links between stressors, hazard assessment and ecosystem services under water scarcity), celebrada en Cádiz el 25 y 26 de noviembre de 2013.The approval of the European Water Framework Dir ective (WFD) supposed a big step regarding aquatic ecosystems protection. According to this Directive, assessment of ecological status is based on three quality elements: biological, physicoc hemical and hydromorphological, but ecotoxicological status is still not included. Some studies have observed that biol ogical status is not always in coherence with physicochemical status, maybe due to the adaptati on mechanisms of aquatic organisms under chronic chemical exposure. In these situations, ecotoxicity t ests could be useful to obtain a better characterisation of these specific ecosystems. The general aim of this work is to add a battery of ecotoxicity tests to the current analyses defined by WFD in order to obtain a better ecological characteriza tion of freshwater systems. The specific aims of this work are: (1) to compare the effectiveness and viability of differen t ecotoxicity tests performed with freshwater sediments (directly and with pore water) ta king as target organisms different aquatic species, and (2) to evaluate the relationship between stream pollutants concentrations (organic pollutants and metals), biological and hydromorphological status and sediments ecotoxicity. For this purpose, thirteen sampling sites within the Ebro river watershed were selected. Data about priority pollutants in water, sediment and fish as well as biological and hydromor phological status of each sampling point will be achieved. Moreover, in each sampling reach, composite samples of sediment were collected by using a Van Veen grab. Sediment samples were stored at 4ºC prior to the ecotoxicity analysesThe ecotoxicity of pore water was evaluated by different bioassays ( Vibrio fischeri, Pseudokirshneriella subcapitata and Daphnia magna ) while the ecotoxicity of wh ole sediment was evaluated in Vibrio fischeri, Nitzschia palea and Chironomus riparius In addition, the concentration of total heavy metals and metal bioavailability was calculated by a sequential extraction according to the Community Bureau of Reference (BCR) method. To distinguish the potentially toxic fraction associated to heavy metals burden of sediments, an analysis of acid-volatile sulphide (AVS) and simultaneously extracted metals (SEM) was performed. Complementary sediment variables as humi dity, porosity, percentages of fines (<63 μm) organic carbon and organic matter were determined. This study expect to demonstrate that the integr ation of chemical, biological and ecotoxicological analyses could be crucial to unde rstand the hazard of pollutants in aquatic ecosystems, especially, in freshwater sediments. Future research in this area is needed in order to obtain more data and be able to establish a tree decision of freshwater analyses ev aluation. The poster will present the methodology purposed for this study as well as the first prelim inary results obtained from ecotoxicity tests.Authors would like to thank the Spanish Ministry of Economy and Competitiveness for its financial support through the project SCARCE (Consolider-Ingenio 2010 CSD2009-00065Peer Reviewe

Efectos de la salinidad sobre el crecimiento, la fluorescencia de clorofila y el drift de la microalga bentónica Cylindrotheca closterium

Trabajo presentado en el XVII Iberian Symposium on Marine Biology Studies, celebrado en San Sebastián del 11 a 14 de septiembre de 2012.En el presente trabajo se evaluó el efecto de la salinidad sobre el crecimiento poblacional, la fluorescencia de clorofila y el drift (desplazamiento pasivo en la corriente de agua) de Cylindrotheca closterium. C. closterium es una microalga bentónica que habita zonas estuarinas formando parte del microfitobentos. Entre los factores de estrés que pueden afectar a la especie C. closterium se encuentran los cambios de salinidad. En una primera fase, estos efectos se evaluaron en base al crecimiento poblacional en ensayos de toxicidad estándar realizados en matraz. Las células de C. closterium fueron expuestas a diferentes salinidades, que variaron de 37 (control) hasta 5, durante 72 h, bajo condiciones controladas temperatura y luz constante. El drift y la fluorescencia de clorofila se midieron simultáneamente como marcadores de exposición al estrés. Para ello se diseñó y construyó un sistema de flujo continuo (Figura 1) que permitiera examinar la capacidad de C. closterium de evitar los efectos de la salinidad mediante el drift. El sistema estaba compuesto de 3 compartimentos interconectados de 35 mL cada uno. Los dos compartimentos iniciales fueron usados para reducir la turbulencia del agua y evitar el arrastre de las microalgas colocadas en el tercer compartimento. Un flujo de agua constante de 480±15 mL min-1 era generado mediante una bomba contenida en un recipiente donde era recogida el agua una vez salía del sistema, creando así un circuito cerrado y continuo. La entrada de agua de la bomba fue cubierta con un filtro de 5 µm de luz de malla para evitar que las microalgas que realizaban drift retornaran al sistema. El circuito contenía 500 mL de agua de mar filtrada a la que se añadió medio f/2 y silicatos. Seis horas antes del inicio del ensayo se colocaban las microalgas, con una concentración de 104 células mL-1, en el tercer compartimento del sistema para garantizar que estas decantaran en el fondo. A continuación el sistema era puesto en marcha durante 12 h y en oscuridad para evitar el crecimiento de la población de microalgas. Se realizaron ensayos a diferentes salinidades (37, 30, 24, 19, 15, 12 y 9) que fueron repetidos cuatro veces en el tiempo. El número de células que hizo drift fue determinado en función de la fluorescencia de clorofila de modo que ambas respuestas, drift y reducción en la fluorescencia de clorofila fueron integradas en una misma medida. Los datos de inhibición de crecimiento indican que la salinidad que causa una reducción en la población del 50% (ES50) fue de 19±4; por otro lado la ES50 calculada a partir del sistema de drift integrando la fuga y la fluorescencia de clorofila fue de 15±3. Los resultados del estudio mostraron que un descenso de la salinidad provoca una disminución en el crecimiento de C. closterium, además produce una disminución en la fluorescencia de clorofila y desencadena la respuesta de drift.Peer Reviewe

Pastores trashumantes del Neolítico antiguo en un entorno de alta montaña: secuencia crono-cultural de la Cova de Els Trocs (San Feliú de Veri, Huesca)

This paper presents the preliminary results of the excavation of the “Els Trocs’’ Cave, developed in the context of the research project “The pathways of the Neolithic”. The careful and detailed work of excavation and recording has revealed a complex stratigraphy in which, thanks to the radiocarbon dates on short-lived samples (cereal seeds, human bones and domestic animal remains), it has been possible to distinguish four different periods of occupation inside the cave. With this information and some preliminary analyses of part of the materials (pottery, flint and faunal remains), we have documented the presence of a human group in the mountain pastures of the axial Pyrennes, at a very early stage (beginning of the last third of the Vlth millennium cal. BC), with a transhumant pastoral economy. It was a fully neolithic population with clear evidences of the use of wheat and barley, despite they did not cultivate around the close environment of this cave, where complex burial rituals had been also documented.Este trabajo presenta los resultados preliminares obtenidos en la excavación de la Cova de Els Trocs, desarrollada dentro del proyecto de investigación "Los caminos del Neolítico". La minuciosa labor de excavación y de registro ha permitido establecer una compleja secuencia estratigráfica en la que, gracias a una veintena de dataciones radiocarbónicas sobre eventos singulares de vida corta (semillas de cereal, huesos humanos y fauna doméstica), se han podido diferenciar cuatro momentos de ocupación distintos de la cueva. Con estos datos y algunos análisis, también preliminares, de parte del registro (cerámica, sílex y restos faunísticos), se ha podido definir, en una época muy temprana (inicios del último tercio del VI milenio cal. BC.), la presencia en los pastos de montaña del Pirineo axial de un grupo humano que desarrolla una actividad pastoril trashumante. Una población plenamente neolitizada, que conoce el trigo y la cebada, aunque no los cultive en el entorno de la cueva, y que, a tenor de ciertas evidencias, practica complejos rituales tanatológicos

Evaluation of Adipose Tissue Zinc-Alpha 2-Glycoprotein Gene Expression and Its Relationship with Metabolic Status and Bariatric Surgery Outcomes in Patients with Class III Obesity

Zinc-α2 glycoprotein (ZAG) is an adipokine involved in adipocyte metabolism with potential implications in the pathogenesis of metabolic disorders. Our aim was to evaluate the relationship between visceral (VAT) and subcutaneous adipose tissue (SAT) ZAG expression and metabolic parameters in patients with class III obesity, along with the impact of basal ZAG expression on short- and medium-term outcomes related to bariatric surgery. 41 patients with class III obesity who underwent bariatric surgery were included in this study. ZAG gene expression was quantified in SAT and VAT. Patients were classified into two groups according to SAT and VAT ZAG percentile. Anthropometric and biochemical variables were obtained before and 15 days, 45 days, and 1 year after surgery. The lower basal SAT ZAG expression percentile was associated with higher weight and waist circumference, while the lower basal VAT ZAG expression percentile was associated with higher weight, waist circumference, insulin, insulin resistance, and the presence of metabolic syndrome. Basal SAT ZAG expression was inversely related to weight loss at 45 days after surgery, whereas no associations were found between basal VAT ZAG expression and weight loss after surgery. Additionally, a negative association was observed between basal SAT and VAT ZAG expression and the decrease of gamma-glutamyl transferase after bariatric surgery. Therefore, lower SAT and VAT ZAG expression levels were associated with an adverse metabolic profile. However, this fact did not seem to confer worse bariatric surgery-related outcomes. Further research is needed to assess the clinical significance of the role of ZAG expression levels in the dynamics of hepatic enzymes after bariatric surgeryThis study has been co-funded by FEDER funds (“A way to make Europe”). M.M. and L.G.S. are also supported by UMA18-FEDERJA-285 and UMA20-FEDERJA-144, co-funded by Malaga University, Junta de Andalucía and FEDER funds, CB06/03/0018, PI-0297-2018 and PI-0194-2017, co-funded by FEDER funds and Consejería de Salud y Familias, Junta de Andalucía, and CP17/00133, Instituto de Salud Carlos III (ISCIII), Ministry of Science, Innovation and Universities, Spain Partial funding for open access charge: Universidad de Málag