Point Centred Variography to Assess the Spatial Representativeness of Air Quality Monitoring Sites: Application to the Datasets of the FAIRMODE Intercomparison Exercise of Spatial Representativeness

Common definitions for the spatial representativeness of air quality monitoring sites are based on the evaluation of the similarity of pollutant concentrations, in which the representativeness area of a monitoring site is basically described by the set of all locations where the concentration of a pollutant does not differ from the measurements at the central point by more than a certain threshold. Classical geostatistical analysis describes the spatial correlation structure of a concentration field in terms of the variogram. In contrary, the point centred variography is based on the average of squared concentration differences observed in pairs formed between a particular central point and the set of all other points in the domain. It thereby places a monitoring station in the context of the local or regional air quality pattern. In this report we demonstrate how a mathematical inversion of the point centred variogram can provide information about the extent of the spatial representativeness area of a monitoring site. The application of this approach is tested on a set of modelling data from the city of Antwerp. This dataset contains information at a very high spatial (street level) and temporal resolution for three main pollutants (PM10, NO2 and Ozone), over the whole city. Furthermore, FAIRMODE (Forum for Air Quality Modeling in Europe) is currently concluding an intercomparison exercise on spatial representativeness methods, which is also based on sharing this same dataset.JRC.C.5-Air and Climat

Screening tools for data quality and outlier detection applied to the Airbase ambient air pollution database

In order to provide scientifically sound information for regulatory purposes and environmental impact assessment, long term meso- to large-scale datasets of ambient air quality provide an indispensible means for model calibration, evaluation and validation. However, the collection of high quality datasets with suitable spatial coverage for air pollution management and decision support poses many challenges. It is thus critical to establish expedient tools for the efficient assessment and data quality control of air pollution measurements in large scale national and international monitoring networks. The European Environmental Agency collects, in the Air Quality Database named AirBase, measurements of ambient air pollution at more than 6000 monitoring stations from over 30 countries. The quality of these data depends on the chosen method of measurements and QA/QC procedures applied by each country. We present a methodology to automatically screen the AirBase records for internal consistency and to detect spatio-temporal outliers nested in the data. We implemented a spatial-set outlier detection method, which considers both attribute values and spatial relationships. Specifically, we adapted the “Smooth Spatial Attribute method” that was developed for the identification of outliers in traffic sensors. The method relies on the definition of a neighbourhood for each air pollutant measurement, corresponding to a spatio-temporal domain limited in time (+/- 1 day) and distance (+/- 1 degree) around location x. It is assumed that within a given spatio-temporal domain in which the attribute values of neighbours have a relationship due to the emission, transport and reaction of air pollutants, outliers will be detected by extreme values of their attributes compared to the attribute values of their neighbours. The implemented method can be of interest as a data quality screening system when countries report their measurements to the European Environment Agency. Beyond this, it could also provide a simple solution to investigate the accuracy of station classification in AirBase.JRC.H.2-Air and Climat

FAIRMODE Spatial representativeness feasibility study

Within Fairmode, it is planned to organize an intercomparison exercise of methods for the assessment of the spatial representativeness of monitoring sites. It is expected that the outcomes of the proposed intercomparison exercise will substantially support future efforts towards a harmonized methodological framework to facilitate the reporting of spatial representativeness by the Member States. This report presents a feasibility study including a Bibliographical review of the studies done for experts published in scientific journals or technical reports , a tentative definition of the concept of spatial representativeness after reviewing the papers and reports found in the bibliographical review , the development of a questionnaire to get technical information of the methodologies used to estimate the area of representativeness of air quality monitoring stations by the main expert groups in Europe, an analysis of the survey results and a discussion about the feasibility of an intercomparison exercise for methodologies estimating the spatial representativeness of monitoring stations.JRC.H.2-Air and Climat

Origin and genesis of dissolved organic matter: a study by Py-GC/MS-IRMS

Dissolved organic matter (DOM) is influenced by the diversity of potential sources and processes which results in a heterogeneous mixture with a characteristic organic chemical signature for individual aquatic ecosystems. Reference samples (DFG-Special Research Program ROSIG) from natural systems such as a bog lake, groundwater and soil percolate but also from anthropogenically influenced systems like a brown coal processing waste water reservoir and a waste water treatment plant were taken to identify common characteristics and differences with respect to the origin and genesis of the DOM. This was achieved by a new analytical approach where fragments of the DOM resulting from thermal degradation (Curie-point pyrolysis at 773 K) were hromatographically separated, identified, and analyzed for their isotopic content (Py-GC/MS-IRMS). The applicability of the analytical method was manifested and additionally used for a comparison of the DOM from a bog lake with a set of samples from different depths of the surrounding moss vegetation

FAIRMODE Intercomparison exercise - Dataset to assess the area of representativeness of Air Quality Monitoring Stations

A feasibility study for organizing an intercomparison exercise (IE) of the methods used for estimating of the area of representativeness of the Air Quality Monitoring Stations (SR) in Europe has been carried out. It showed that it should be possible to compare the extent of SR determined by the different methods. Moreover, at the FAIRMODE-Aveiro meeting in 2015, the participants agreed to carry out the intercomparison exercise assessing the SR estimates for PM10 and NO2 at one traffic station, and for PM10, NO2 and O3 at two urban background stations. This report presents a dataset suitable for the FAIRMODE IE of the area of representativeness of Air Quality Monitoring Stations in the urban area of Antwerp (Belgium) for the year 2012. Three monitoring stations, Borgerhout-Straatkant, Antwerpen-Linkeroever and Schoten, have been selected for the evaluation. The dataset includes the model results for interpolated annual means on a fine regular grid, hourly time series at a number of 341 virtual receptor points to which random noise have been added, data from measurements of the Antwerp automatic monitoring stations, individual sampling campaigns, emissions, traffic, population density, building information, gridded CORINE land cover data, a short summary of PM10 speciated data and daily time profiles for traffic.JRC.C.5-Air and Climat

The coactivator role of histone deacetylase 3 in IL-1-signaling involves deacetylation of p65 NF-κB

Histone deacetylase (HDAC) 3, as a cofactor in co-repressor complexes containing silencing mediator for retinoid or thyroid-hormone receptors (SMRT) and nuclear receptor co-repressor (N-CoR), has been shown to repress gene transcription in a variety of contexts. Here, we reveal a novel role for HDAC3 as a positive regulator of IL-1-induced gene expression. Various experimental approaches involving RNAi-mediated knockdown, conditional gene deletion or small molecule inhibitors indicate a positive role of HDAC3 for transcription of the majority of IL-1-induced human or murine genes. This effect was independent from the gene regulatory effects mediated by the broad-spectrum HDAC inhibitor trichostatin A (TSA) and thus suggests IL-1-specific functions for HDAC3. The stimulatory function of HDAC3 for inflammatory gene expression involves a mechanism that uses binding to NF-κB p65 and its deacetylation at various lysines. NF-κB p65-deficient cells stably reconstituted to express acetylation mimicking forms of p65 (p65 K/Q) had largely lost their potential to stimulate IL-1-triggered gene expression, implying that the co-activating property of HDAC3 involves the removal of inhibitory NF-κB p65 acetylations at K122, 123, 314 and 315. These data describe a novel function for HDAC3 as a co-activator in inflammatory signaling pathways and help to explain the anti-inflammatory effects frequently observed for HDAC inhibitors in (pre)clinical us

The coactivator role of histone deacetylase 3 in IL-1-signaling involves deacetylation of p65 NF-kappaB

Histone deacetylase (HDAC) 3, as a cofactor in co-repressor complexes containing silencing mediator for retinoid or thyroid-hormone receptors (SMRT) and nuclear receptor co-repressor (N-CoR), has been shown to repress gene transcription in a variety of contexts. Here, we reveal a novel role for HDAC3 as a positive regulator of IL-1-induced gene expression. Various experimental approaches involving RNAi-mediated knockdown, conditional gene deletion or small molecule inhibitors indicate a positive role of HDAC3 for transcription of the majority of IL-1-induced human or murine genes. This effect was independent from the gene regulatory effects mediated by the broad-spectrum HDAC inhibitor trichostatin A (TSA) and thus suggests IL-1-specific functions for HDAC3. The stimulatory function of HDAC3 for inflammatory gene expression involves a mechanism that uses binding to NF-?B p65 and its deacetylation at various lysines. NF-?B p65-deficient cells stably reconstituted to express acetylation mimicking forms of p65 (p65 K/Q) had largely lost their potential to stimulate IL-1-triggered gene expression, implying that the co-activating property of HDAC3 involves the removal of inhibitory NF-?B p65 acetylations at K122, 123, 314 and 315. These data describe a novel function for HDAC3 as a co-activator in inflammatory signaling pathways and help to explain the anti-inflammatory effects frequently observed for HDAC inhibitors in (pre)clinical use

The Inflammatory Kinase MAP4K4 Promotes Reactivation of Kaposi's Sarcoma Herpesvirus and Enhances the Invasiveness of Infected Endothelial Cells

Kaposi's sarcoma (KS) is a mesenchymal tumour, which is caused by Kaposi's sarcoma herpesvirus (KSHV) and develops under inflammatory conditions. KSHV-infected endothelial spindle cells, the neoplastic cells in KS, show increased invasiveness, attributed to the elevated expression of metalloproteinases (MMPs) and cyclooxygenase-2 (COX-2). The majority of these spindle cells harbour latent KSHV genomes, while a minority undergoes lytic reactivation with subsequent production of new virions and viral or cellular chemo- and cytokines, which may promote tumour invasion and dissemination. In order to better understand KSHV pathogenesis, we investigated cellular mechanisms underlying the lytic reactivation of KSHV. Using a combination of small molecule library screening and siRNA silencing we found a STE20 kinase family member, MAP4K4, to be involved in KSHV reactivation from latency and to contribute to the invasive phenotype of KSHV-infected endothelial cells by regulating COX-2, MMP-7, and MMP-13 expression. This kinase is also highly expressed in KS spindle cells in vivo. These findings suggest that MAP4K4, a known mediator of inflammation, is involved in KS aetiology by regulating KSHV lytic reactivation, expression of MMPs and COX-2, and, thereby modulating invasiveness of KSHV-infected endothelial cells. © 2013 Haas et al

NFκB activation by Fas is mediated through FADD, caspase-8, and RIP and is inhibited by FLIP

Fas (APO-1/CD95) is the prototypic death receptor, and the molecular mechanisms of Fas-induced apoptosis are comparably well understood. Here, we show that Fas activates NFκB via a pathway involving RIP, FADD, and caspase-8. Remarkably, the enzymatic activity of the latter was dispensable for Fas-induced NFκB signaling pointing to a scaffolding-related function of caspase-8 in nonapoptotic Fas signaling. NFκB was activated by overexpressed FLIPL and FLIPS in a cell type–specific manner. However, in the context of Fas signaling both isoforms blocked FasL-induced NFκB activation. Moreover, down-regulation of both endogenous FLIP isoforms or of endogenous FLIPL alone was sufficient to enhance FasL-induced expression of the NFκB target gene IL8. As NFκB signaling is inhibited during apoptosis, FasL-induced NFκB activation was most prominent in cells that were protected by Bcl2 expression or caspase inhibitors and expressed no or minute amounts of FLIP. Thus, protection against Fas-induced apoptosis in a FLIP-independent manner converted a proapoptotic Fas signal into an inflammatory NFκB-related response

c-Jun N-terminal kinase phosphorylates DCP1a to control formation of P bodies

JNK-mediated phosphorylation of the mRNA-decapping protein DCP1a disrupts P body structure, mRNA stability, and gene expression in response to stress and inflammatory stimuli