484 research outputs found
The Use of Data and Models for Assessing the Equilibrium Partitioning Approach for Analysising Environmental Quality Standards in the Water Column and in the Sediments
An analysis of experimental and simulated data has been performed to study the relationships between EQS defined for surface waters in the Daughter Directive (COM (2006) 397) and possible EQS defined for sediments.
From the above analysis of experimental and simulated data, it is clear that even though there is a coupling between water column and sediments, it is not possible to assess the chemical quality status of sediments based on water column data and viceversa. At the moment EQS have been defined for the water column and therefore these EQS will assess only the compliance with good chemical status of surface waters. If EQS were to be defined for sediments, these EQS will not reflect systematically the surface water quality and therefore they could not be used for this purpose, being the contrary is also true, i.e. compliance with EQS values for water column does not reflect sediment chemical status. However, it is clear that the good chemical quality of a water body will depend on having good chemical quality of surface water and sediments and that to assess both it is necessary to measure in both media.
The same EQS developed for water could, in principle, be applied to porewater, hence, there is no need of developing another set of EQS. If porewater could not be measured, then the partitioning approach to pass to sediment concentrations should be applied. However, in this case an additional uncertainty is added to the procedure and therefore it is necessary to develop to develop new techniques and better databases since at the moment the predictions are between several orders of magnitude, which are not adequate for setting EQS. Additionally, the use of this approach would certainly require the characterization of the sediments in terms of its physical (grain size, material, temperature), chemical (organic matter content, black carbon, pH, redox, etc.) and biological (e.g. bioturbation), which at the moment are not obtained from standard environmental monitoring.JRC.H.5-Rural, water and ecosystem resource
Persistent Organic Pollutants (POPs) in the European Atmosphere: An Updated Overview
POPs are a group of chemicals which share some specific characterictics, that make them of high international concern. Due to their semivolatility, POPs present a widespread distribution being able to reach remote locations and areas after traveling long distances in the atmosphere where they have never been produced nor used. Different chemical families are considered as POPs, such as PCBs, OCPs, PCDD/Fs, PAHs, and, PCNs. In addition, some emerging contaminants are currently considered as candidate POPs, like PBDEs and PFCs. POPs exist in the atmosphere as gases and bound to particles depending on their physico-chemical properties. This affinity to gas or particulate phase is of relevant importance in the processes of POP atmospheric global transport and degradation. POPs are delivered to aquatic and terrestrial ecosystems by atmospheric deposition, air-water interchanges and direct discharges. The general hydrophobic nature of POPs results in high affinity to organic matter and biota tissues. Consequently, organisms and sediments become final sinks of POPs, due to low metabolic activity for these compounds and slow degradation processes in the environment. A number of national and international actions have been promoted to reduce or ban their production and control their emissions to the environment. The UNEP Stockholm Convention adopted in May 2001. The Artic Monitoring and Assessment Programme (AMAP) is measuring atmospheric concentrations of POPs in the artic region since it was established in 1991. At a European scale a big effort is being carried out combining the update of existing monitoring programmes with the generation of new legislations. Such is the case of the largest monitoring network across Europe gathering concentrations of POPs in air and deposition (EMEP). On the political side, the brand new European legislation on chemicals, REACH, will regulate the production of chemicals at a European scale. In addition, other POPs monitoring programmes exist at regional or national scales and a large number of ;independent; sites measuring atmospheric concentrations of POPs are spread out in the European geography. Considering such a scenario it seems obvious that a strong effort in harmonization and communication of results and monitoring and research strategies needs to be achieved. A step to facilitate this needed interaction was the workshop on ;Persistent Organic Pollutants (POPs) in the European Atmosphere ; Concentration, Deposition and Sources in Europe; organized by the European Commission Joint Research Center held in October 17-19th, 2005 in Stresa (Italy). It was one of the objectives of the workshop to gather top experts from Europe and North America to share their expertise on POP monitoring and research in the atmospheric compartment in order to evaluate their current status in Europe. Invited experts develop their professional activities either in the existing POPs monitoring networks or in research institutions closely linked to POPs research. Other objectives of the workshop were to explore future research lines on the topic and to establish links with the existing science and new policies in Europe regarding chemicals. Twenty oral communications were presented covering relevant key issues on POPs:
In this report a compilation of the extended abstracts submitted by the participants is presented, whereas the working result output of the workshop will be submitted as an article to a peer-reviewed scientific journal.JRC.H.5-Rural, water and ecosystem resource
Polychlorinated Biphenyls (PCBs) at the JRC Ispra Site: Air Concentrations, Congener Patterns and Seasonal Variation-Results from the 1st Year of Atmospheric Monitoring of Persistent Organic Pollutants (POPs) at the Ispra EMEP Station
With the aim of gathering information on atmospheric POPs concentrations in one of the ¿monitoring holes¿ in Europe, a monitoring and research atmospheric site was set up at the JRC Ispra Site. Regular monitoring activities started on April 2005 and finished on March 2007 in this first stage. Air and precipitation samples were collected regularly throughout this period. First results obtained on PCBs ambient air concentrations (7 indicator PCBs: 28, 52, 101, 118, 153, 138 and 180) from the first year of monitoring (April 2005-2006) are presented in this report. In addition, congener patterns, air gas/particulate phase partition and seasonal variation are discussed. The range of ¿7 PCB total (gas + particulate phases) monthly averaged concentration during the sampling period varied from 76 ± 17 to 31 ± 5 pg m-3. Concentrations are within the range of those reported for rural, semi-rural or remote areas around the world. A seasonal variation of air concentrations was observed, with higher levels in summer months (higher average temperatures) and lower values in winter (lower average temperatures). In addition, indications of seasonal variation affecting congener patterns and the gas - particulate phase partition for the studied PCB were found. PCBs were in general predominant in the air gas phase, dominating therefore the contribution to the total airborne concentration, although the percentage in the gas phase decreases when increasing level of chlorination and during the low temperature season (winter months).
A one year data set of PCB ambient air concentrations has been generated, constituting a useful dataset that now remains available for further use, such as inclusion in the EMEP network or for POPs fate modelling validation and future risk assessment of POPs in sub-alpine locations. More results for other target POPs are under processing and are expected to be reported soon.JRC.H.5-Rural, water and ecosystem resource
A Compilation of Europe-Wide Databases from Published Measurements of PCBs, Dioxins and Furans
Chemical risk assessment always entails an evaluation of expected environmental concentrations of substances; these concentrations may be predicted using mathematical models or may be chosen on the basis of experimental observations and monitoring activities.
The work discusses the usefulness and limitations in building compilations of published monitoring data by describing a feasibility study on polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), for which observed concentration data were retrieved from scientific journal articles published between 2000 and 2009.
These chemicals are typical POPs and are of constantly high concern for their potential adverse effects on human health and ecosystems. PCBs were mainly used by the power industry in electrical transformers, capacitors, hydraulic equipment, and as lubricants. PCDD/Fs are formed as unintentional by-products of chemical manufacturing and incineration processes, as well as natural processes such as volcanic eruptions, and biomass burning. Emissions from incineration of industrial wastes such as metal reclamation and domestic heating (especially in central Europe) are considered as current sources of PCDD/Fs to the environment.
A database of published observed concentrations of PCBs and PCDD/Fs in air, soil sediments and water was built as described in details in the report. As continental scale assessment is aimed more at the evaluation of the regional distribution of contamination, we excluded from the database those measurements taken close to known PCB or PCCD/F pollution sources of exceptional entity such as waste incinerators or contaminated sites.
After presenting and interpreting the results of the literature search, we critically examine the completeness and usability of this information, and the usefulness of data compilations in the framework of chemical risk assessment.JRC.H.5-Rural, water and ecosystem resource
Microglial response differences between amyloidogenic transgenic models and Alzheimer’s disease patients
Aims: The continuing failure to develop an effective treatment for Alzheimer’s disease (AD) reveals the complexity for AD pathology. Increasing evidence indicates that neuroinflammation involving particularly microglial cells contributes to disease pathogenesis. Here we analyze the differences in the microglial response between APP/PS1 model and human brains.
Methods: RT-PCR, western blots, and immunostaining were performed in the hippocampus of human post mortem samples (from Braak II to Braak V-VI) and APP751SL/PS1M146L mice. In vitro studies to check the effect of S1 fractions on microglial cells were assayed.
Results: In APP based models the high Abeta accumulation triggers a prominent microglial response. On the contrary, the microglial response detected in human samples is, at least, partial or really mild. This patent difference could simple reflect the lower and probably slower Abeta production observed in human hippocampal samples, in comparison with models or could reflect the consequence of a chronic long-standing microglial activation. However, beside this differential response, we also observed a prominent microglial degenerative process in Braak V-VI samples that, indeed, could compromise their normal role of surveying the brain environment and respond to the damage. This microglial degeneration, particularly relevant at the dentate gyrus of the hippocampal formation, might be mediated by the accumulation of toxic soluble phospho-tau species.
Conclusions: These differences need to be considered when delineating animal models that better integrate the complexity of AD pathology and, therefore, guarantee clinical translation. Correcting dysregulated brain inflammatory responses might be a promising avenue to restore cognitive function.
Supported by grants FIS PI15/00796 and FIS PI15/00957 co-financed by FEDER funds from European Union, and by Junta de Andalucia Proyecto de Excelencia CTS385 2035.Financiado por FIS PI15/00796 y FIS PI15/0095, cofinanciado por los fondos FEDER de la Unión Europea, y por Junta de Andalucia Proyecto de Excelencia CTS385 2035.
Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Integración de un Planificador de Trayectorias Parametrizado en la Arquitectura Robótica ROS
En este trabajo se presenta la integración de un nuevo planificador reactivo de movimiento dentro de la arquitectura robótica ROS. Este planificador, desarrollado originalmente como parte de la librería MRPT y basado en el Espacio de Trayectorias Parametrizado (TP-Space), amplia las posibilidades de navegación de las plataformas robóticas actuales mediante la generación de trayectorias tanto circulares como no-circulares, así como la posibilidad de contemplar la geometría 3D del robot (no restringiéndose a formas prismáticas). La integración se ha realizado garantizando la compatibilidad con el stack de navegación autónoma más popular de la plataforma ROS, adaptando el funcionamiento de dicho reactivo a la interfaz de comunicación estándar de ROS, siendo este compatible con los planificadores globales existentes. Para validar este trabajo, se han realizado múltiples pruebas de navegación en entornos de interior (tanto simulados como reales), con presencia de obstáculos y donde la plataforma robótica es equipada con diversas cámaras RGB-D y un escáner láser.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
Proyecto WISER (DPI2017-84827-R), financiado por el Ministerio de Ciencia e Innovación contando con fondos del Fondo Europeo de Desarrollo Regional (FEDER)
Lithium, as a neuroprotective therapy for Alzheimer’s disease pathology, modifies abeta plaque toxicity
BACKGROUND: Despite the relatively large information about the Alzheimer’s disease (AD) pathology, no effective disease-modifying treatment has been yet developed. Lithium, a primary drug to treat bipolar disorder, has been suggested as a potential treatment against AD. In this work we have evaluated whether lithium treatment could ameliorate the neuropathology progression of the transgenic PS1M146L/APPSwe-London mice. Unlike most transgenic animal models, which do not exhibit the neurodegenerative spectrum of disease observed in the patient population, this AD model exhibits a prominent amyloid pathology along with a selective and significant neuronal loss in the hippocampus and entorhinal cortex. Therefore, this model is highly valuable for evaluating the effectiveness of potential neuroprotective therapies for AD.
METHODS: For lithium treatment, PS1/APP mice (3 month old at the beginning of treatment) were fed, ad libitum, with diet supplemented with lithium carbonate (1.2g/kg, Harlan, Spain). The treatment lasts 6 months. After behavioural studies, mice were anesthetized and brains dissected out (hippocampus and cortex). Hemibrains were processed for immunohistochemistry, stereological and image analysis quantification, and the other hemibrains for RT-PCR and Western blot studies.
RESULTS: Our data demonstrate that chronic oral administration of lithium, before the pathology onset, resulted in less toxic plaque formation that significantly ameliorated the degenerative processes and behavioural/memory deficits occurring during disease progression in our PS1/APP model. Specifically, and of great relevance for AD prevention, early lithium intervention was able to arrest neuronal loss in hippocampus and entorhinal cortex of highly vulnerable populations. Besides, lithium reduced the axonal dystrophic pathology, associated to amyloid plaques, by increasing the Abeta compaction. Moreover, a significant lower accumulation of phospho-tau, LC3-II and ubiquitinated proteins was detected. Our study highlights that the switch of plaque quality by lithium could be mediated by astrocyte activation and the release of heat shock proteins, which concentrated in the core of the plaques.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Ambulatory blood pressure monitoring in heart failure and serum sodium levels
Aims: To determine whether there are differences in blood pressure profile on dynamic assessment by ambulatory blood pressure monitoring (ABPM) according to serum sodium levels in stable heart failure patients.Methods: Data were collected from the Spanish National Registry on Ambulatory Blood Pressure Monitoring in Heart Failure (DICUMAP). Patients underwent ABPM by the oscillometric principle using a Spacelabs 90121 monitor. The sample was divided into three groups according to sodium levels and their clinical and laboratory data and echocardiographic findings were analyzed. Robust statistical methods were used to compare the groups in univariate and multivariate models.Results: A total of 175 patients (44.57% male) were analyzed. We found a predominance of anomalous circadian blood pressure profiles in all three groups, with a significantly higher percentage of risers in the lowest serum sodium group (p=0.05). In addition, in this group there were significant differences in mean 24-hour systolic blood pressure (SBP) (24-h SBP, p=0.05) and in mean daytime SBP (dSBP, p=0.008), with significant differences in nocturnal fall in SBP (p=0.05) and in diastolic blood pressure (p=0.005). In multivariate analysis a significant relationship was found between sodium levels and 24-h SBP (OR 0.97, 95% CI 0.95-0.99, p=0.01) and dSBP (OR 0.96, 95% CI 0.94-0.99, p=0.004).Conclusion: A relationship was found between lower sodium levels and lower systolic blood pressure, especially during waking hours, with a lower decline between daytime and night-timeblood pressure
Comparison of Monitoring Approaches for Selected Priority Pollutants in Surface Water - An Initiative in support to the Water Framework Directive Chemical Monitoring Activity
Laboratories from seven EU Member States under the coordination of the Joint Research Centre and in collaboration with the Provincia di Ferrara participated in a technical on-site project during which sampling and analytical methodologies for chemical monitoring according to proposed WFD provisions have been compared. Laboratories had been invited to take samples from a river according to their standard protocols and to analyse them for PAHs, PBDE and Nonyl-, Octylphenol. It was shown that it is possible to analyse contaminants at relevant levels. Results showed also that currently only experienced laboratories can achieve the required performance, indicating the need for improvement at European level.JRC.H.5-Rural, water and ecosystem resource
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