57 research outputs found
Charakterisierung der Effekte von RegenwĂŒrmern auf die Wasserverteilungs- und NĂ€hrstoffdynamik in urbanen Böden
The influence of soil fauna on turnover processes and nutrient cycling in terrestrial habitats is fairly well studied. By contrast, the impact of the burrowing, feeding and excreting activity of soil animals on the physical characteristics of soils is far from being understood, even less if we consider anthropogenically shaped environments like urban habitats. Urbanization, though, is a major ongoing land use change worldwide and it is of particular interest to understand the functioning of urban ecosystems and the provision of ecosystem services useful to man in urban areas (e.g. provision of clean drinking water, reduction of flood risk, mitigation of climate change consequences) all linked to the capacity of urban soils to infiltrate, conduct, filter and store water from the soil surface. Aim of the subproject FAUNA within the research group was to characterize the functional impact of soil animals on turnover processes and on the water distribution dynamics in urban soils.
In a series of experiments with mesocosms in field and lab, we studied how the burrowing activity of endogeic earthworms and the mixing of soil particles with excretion products may modify the structure of the soil horizons, the water distribution patterns and the processes of nutrient release in urban soils. The set up of mesocosms equipped with electrodes for the measurements of Electical Resistivity Tomography (ERT) and Time Domain Reflectometry (TDR) probes allowed to trace in situ and noninvasively subsequent desiccation, infiltration and rewetting processes in the soils. The soil animals greatly modified the infiltration and the storage of water in the soils. This occurred interestingly not in reducing the specific actual hydrophobicity of the soils, but by changing the pore size distribution, increasing the saturated water conducitivity and enhancing clearly the water contents in the urban soil horizonts
Scientific Opinion about the Guidance of the Chemical Regulation Directorate (UK) on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessments
Abstract The EFSA Panel on Plant Protection Products and their Residues reviewed the guidance on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessment. The inclusion of aged sorption is a higher tier in the groundwater leaching assessment. The Panel based its review on a test with three substances taken from a data set provided by the European Crop Protection Association. Particular points of attention were the quality of the data provided, the proposed fitting procedure of aged sorption experiments and the proposed method for combining results obtained from aged sorption studies and lowerâtier studies on degradation and adsorption. Aged sorption was a relevant process in all cases studied. The test revealed that the guidance could generally be well applied and resulted in robust and plausible results. The Panel considers the guidance suitable for use in the groundwater leaching assessment after the recommendations in this Scientific Opinion have been implemented, with the exception of the use of field data to derive aged sorption parameters. The Panel noted that the draft guidance could only be used by experienced users because there is no software tool that fully supports the work flow in the guidance document. It is therefore recommended that a userâfriendly software tool be developed. Aged sorption lowered the predicted concentration in groundwater. However, because aged sorption experiments may be conducted in different soils than lowerâtier degradation and adsorption experiments, it cannot be guaranteed that the higher tier predicts lower concentrations than the lower tier, while lower tiers should be more conservative than higher tiers. To mitigate this problem, the Panel recommends using all available higherâ and lowerâtier data in the leaching assessment. The Panel further recommends that aged sorption parameters for metabolites be derived only from metaboliteâdosed studies. The formation fraction can be derived from parentâdosed degradation studies, provided that the parent and metabolite are fitted with the bestâfit model, which is the double firstâorder in parallel model in the case of aged sorption
Investigation into experimental toxicological properties of plant protection products having a potential link to Parkinson's disease and childhood leukaemia
In 2013, EFSA published a literature review on epidemiological studies linking exposure to pesticides and human health outcome. As a follow up, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to investigate the plausible involvement of pesticide exposure as a risk factor for Parkinson's disease (PD) and childhood leukaemia (CHL). A systematic literature review on PD and CHL and mode of actions for pesticides was published by EFSA in 2016 and used as background documentation. The Panel used the Adverse Outcome Pathway (AOP) conceptual framework to define the biological plausibility in relation to epidemiological studies by means of identification of specific symptoms of the diseases as AO. The AOP combines multiple information and provides knowledge of biological pathways, highlights species differences and similarities, identifies research needs and supports regulatory decisions. In this context, the AOP approach could help in organising the available experimental knowledge to assess biological plausibility by describing the link between a molecular initiating event (MIE) and the AO through a series of biologically plausible and essential key events (KEs). As the AOP is chemically agnostic, tool chemical compounds were selected to empirically support the response and temporal concordance of the key event relationships (KERs). Three qualitative and one putative AOP were developed by the Panel using the results obtained. The Panel supports the use of the AOP framework to scientifically and transparently explore the biological plausibility of the association between pesticide exposure and human health outcomes, identify data gaps, define a tailored testing strategy and suggests an AOPâs informed Integrated Approach for Testing and Assessment (IATA)
The management of desmoid tumours: A joint global consensus-based guideline approach for adult and paediatric patients
Abstract Desmoid tumor (DT; other synonymously used terms: Desmoid-type fibromatosis, aggressive fibromatosis) is a rare and locally aggressive monoclonal, fibroblastic proliferation characterised by a variable and often unpredictable clinical course. Previously surgery was the standard primary treatment modality; however, in recent years a paradigm shift towards a more conservative management has been introduced and an effort to harmonise the strategy amongst clinicians has been made. We present herein an evidence-based, joint global consensus guideline approach to the management of this disease focussing on: molecular genetics, indications for an active treatment, and available systemic therapeutic options. This paper follows a one-day consensus meeting held in Milan, Italy, in June 2018 under the auspices of the European Reference Network for rare solid adult cancers, EURACAN, the European Organisation for Research and Treatment of Cancer (EORTC) Soft Tissue and Bone Sarcoma Group (STBSG) as well as Sarcoma Patients EuroNet (SPAEN) and The Desmoid tumour Research Foundation (DTRF). The meeting brought together over 50 adult and pediatric sarcoma experts from different disciplines, patients and patient advocates from Europe, North America and Japan
PCDD/Fs in sediments of Central Vietnam coastal lagoons: In search of TCDD
Samples from nine Central Vietnam coastal lagoons, together with three soils and sediments collected in 24
two freshwater reservoirs of the Thua Thien-Hué province, were analysed for polychlorinated dibenzo-p- 25
dioxins and dibenzofurans (PCDD/Fs). Total concentrations are low, from 192 to 2912 pg g1 and depth 26
profiles in Tam Giang-Cau Hai (TG-CH) sediment cores show only minor changes over time in PCDD/F 27
input and composition. Octachloro dibenzo-p-dioxin (OCDD) is the prevailing congener (approximately 28
90%), indicating combustion as the main PCDD/F source to these coastal systems, whereas natural forma- 29
tion might be partly responsible for the presence at depth. 2,3,7,8-Tetrachloro dibenzo-p-dioxin (TCDD), 30
largely sprayed together with Agent Orange over the study areas during the war (1961â1971), is absent 31
or very low. This result supports the hypothesis of strong degradation soon after spraying. Multivariate 32
statistical analyses account for the presence of local, short-range sources as observed in the northern part 33
of the TG-CH lagoon
The next generation neutrino telescope: IceCube-Gen2
The IceCube Neutrino Observatory, a cubic-kilometer-scale neutrino detector at the geographic South Pole, has reached a number of milestones in the field of neutrino astrophysics: the discovery of a high-energy astrophysical neutrino flux, the temporal and directional correlation of neutrinos with a flaring blazar, and a steady emission of neutrinos from the direction of an active galaxy of a Seyfert II type and the Milky Way. The next generation neutrino telescope, IceCube-Gen2, currently under development, will consist of three essential components: an array of about 10,000 optical sensors, embedded within approximately 8 cubic kilometers of ice, for detecting neutrinos with energies of TeV and above, with a sensitivity five times greater than that of IceCube; a surface array with scintillation panels and radio antennas targeting air showers; and buried radio antennas distributed over an area of more than 400 square kilometers to significantly enhance the sensitivity of detecting neutrino sources beyond EeV. This contribution describes the design and status of IceCube-Gen2 and discusses the expected sensitivity from the simulations of the optical, surface, and radio components
Sensitivity of IceCube-Gen2 to measure flavor composition of Astrophysical neutrinos
The observation of an astrophysical neutrino flux in IceCube and its detection capability to separate between the different neutrino flavors has led IceCube to constraint the flavor content of this flux. IceCube-Gen2 is the planned extension of the current IceCube detector, which will be about 8 times larger than the current instrumented volume. In this work, we study the sensitivity of IceCube-Gen2 to the astrophysical neutrino flavor composition and investigate its tau neutrino identification capabilities. We apply the IceCube analysis on a simulated IceCube-Gen2 dataset that mimics the High Energy Starting Event (HESE) classification. Reconstructions are performed using sensors that have 3 times higher quantum efficiency and isotropic angular acceptance compared to the current IceCube optical modules. We present the projected sensitivity for 10 years of data on constraining the flavor ratio of the astrophysical neutrino flux at Earth by IceCube-Gen2
Mechanical design of the optical modules intended for IceCube-Gen2
IceCube-Gen2 is an expansion of the IceCube neutrino observatory at the South Pole that aims to increase the sensitivity to high-energy neutrinos by an order of magnitude. To this end, about 10,000 new optical modules will be installed, instrumenting a fiducial volume of about 8 km3. Two newly developed optical module types increase IceCubeâs current sensitivity per module by a factor of three by integrating 16 and 18 newly developed four-inch PMTs in specially designed 12.5-inch diameter pressure vessels. Both designs use conical silicone gel pads to optically couple the PMTs to the pressure vessel to increase photon collection efficiency. The outside portion of gel pads are pre-cast onto each PMT prior to integration, while the interiors are filled and cast after the PMT assemblies are installed in the pressure vessel via a pushing mechanism. This paper presents both the mechanical design, as well as the performance of prototype modules at high pressure (70 MPa) and low temperature (â40âC), characteristic of the environment inside the South Pole ice
Estimating the coincidence rate between the optical and radio array of IceCube-Gen2
The IceCube-Gen2 Neutrino Observatory is proposed to extend the all-flavour energy range of IceCube beyond PeV energies. It will comprise two key components: I) An enlarged 8km3 in-ice optical Cherenkov array to measure the continuation of the IceCube astrophysical neutrino flux and improve IceCube\u27s point source sensitivity above âŒ100TeV; and II) A very large in-ice radio array with a surface area of about 500km2. Radio waves propagate through ice with a kilometer-long attenuation length, hence a sparse radio array allows us to instrument a huge volume of ice to achieve a sufficient sensitivity to detect neutrinos with energies above tens of PeV.
The different signal topologies for neutrino-induced events measured by the optical and in-ice radio detector - the radio detector is mostly sensitive to the cascades produced in the neutrino interaction, while the optical detector can detect long-ranging muon and tau leptons with high accuracy - yield highly complementary information. When detected in coincidence, these signals will allow us to reconstruct the neutrino energy and arrival direction with high fidelity. Furthermore, if events are detected in coincidence with a sufficient rate, they resemble the unique opportunity to study systematic uncertainties and to cross-calibrate both detector components
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