Understanding heterogeneities of flow paths for agricultural practice

Heterogeneous flow processes, especially preferential flow, facilitate the influx of contaminants (and nutrients) through the soil into the groundwater. With a combination of soil physical, soil chemical and soil geophysical methods we investigate the susceptibility of selected soils for such flow processes on agricultural fields in Lower Saxony. Investigations are performed within the EU Interreg project TOPSOIL which investigates opportunities to improve surface and groundwater quality as well as water management strategies under the consideration of climate adaptation challenges. The project addresses the transport behavior of percolation water in the unsaturated zone, the migration of nitrogen and veterinary pharmaceuticals in soils, and elaborates - together with different stakeholders (e.g. farmers, water supply companies) - common strategies to minimize the migration of these substances into the groundwater. We present results of a first soil scientific and soil geophysical census using radiometry and electrical conductivity which shows the heterogeneity of the site with regard to conductivity and radiation. We used the CMD explorer for electromagnetic mapping (horizontal and vertical dipoles, intercoil spacing of 1.48/2.82/4.49 m, investigation depths of appr. 0 - 6 m). The radiometry detector comprised five sodium-iodide crystals each with a volume of 4 litres. The spectral data are evaluated for potassium, uranium (Bi-214), thorium (T-208) and total counts. The geophysical measurements were used to generally differentiate areas of different soil properties. These areas were sampled for soil physics and soil chemistry (ram coring at 48 sites, 0 - 2 m) with the aim of determining the variability of the transport behavior on a field scale

Antimicrobial Peptides in Gastrointestinal Inflammation

Acute and chronic inflammations of mucosal surfaces are complex events in which the effector mechanisms of innate and adaptive immune systems interact with pathogenic and commensal bacteria. The role of constitutive and inducible antimicrobial peptides in intestinal inflammation has been investigated thoroughly over the recent years, and their involvement in various disease states is expanded ever more. Especially in the intestines, a critical balance between luminal bacteria and the antimicrobial peptides is essential, and a breakdown in barrier function by impaired production of defensins is already implicated in Crohn's disease. In this paper, we focus on the role of antimicrobial peptides in inflammatory processes along the gastrointestinal tract, while considering the resident and pathogenic flora encountered at the specific sites. The role of antimicrobial peptides in the primary events of inflammatory bowel diseases receives special attention

Transitions Induced by the Discreteness of Molecules in a Small Autocatalytic System

Autocatalytic reaction system with a small number of molecules is studied numerically by stochastic particle simulations. A novel state due to fluctuation and discreteness in molecular numbers is found, characterized as extinction of molecule species alternately in the autocatalytic reaction loop. Phase transition to this state with the change of the system size and flow is studied, while a single-molecule switch of the molecule distributions is reported. Relevance of the results to intracellular processes are briefly discussed.Comment: 5 pages, 4 figure

Visual Analysis of Place Connectedness by Public Transport

The concept of place connectedness (traditionally termed `accessibility') refers to the ability of people to reach various services and to participate in activities. Connectedness by public transport is especially important for underprivileged and elderly people while the active use of public transport by the general population contributes in reducing traffic congestions and air pollution in cities. Place connectedness analyses are performed for a variety of purposes. In communication with transportation experts, we performed the conceptual modeling of the domain of problems related to place connectedness, defined the system of analysis tasks, and matched the tasks to visual analytics techniques that are capable to support them. In this paper, we introduce the task typology and present the visual analytics techniques using several example scenarios of place connectedness analyses

Ambient vibration measurements in the Southern Rhine Graben close to Basle

This study presents results of ambient noise measurements from temporary single station and small-scale array deployments in the northeast of Basle. H/V spectral ratios were determined along various profiles crossing the eastern masterfault of the Rhine Rift Valley and the adjacent sedimentary rift fills. The fundamental H/V peak frequencies are decreasing along the profile towards the eastern direction being consistent with the dip of the tertiary sediments within the rift. Using existing empirical relationships between H/V frequency peaks and the depth of the dominant seismic contrast, derived on basis of the ?/4-resonance hypothesis and a power law depth dependence of the S-wave velocity, we obtain thicknesses of the rift fill from about 155 m in the west to 280 m in the east. This is in agreement with previous studies. The array analysis of the ambient noise wavefield yielded a stable dispersion relation consistent with Rayleigh wave propagation velocities. We conclude that a significant amount of surface waves is contained in the observed wavefield. The computed ellipticity for fundamental mode Rayleigh waves for the velocity depth models used for the estimation of the sediment thicknesses is in agreement with the observed H/V spectra over a large frequency band

A double parton scattering background to Higgs boson production at the LHC

The experimental capability of recognizing the presence of b quarks in complex hadronic final states has addressed the attention towards final states with b\bar{b} pairs for observing the production of the Higgs boson at the LHC, in the intermediate Higgs mass range.We point out that double parton scattering processes are going to represent a sizeable background to the process.Comment: 9 pages, 2 figure

Collaboration in electronic resource provision in university libraries: SHEDL, a Scottish case study

This case study examines the growth of collaboration among Scottish higher education institutions. Following a summary of the work of the Scottish Confederation of University and Research Libraries (SCURL), more detailed information is provided on collaboration in the fields of acquisition, licensing, selection, and purchasing. Some of the UK background is outlined, relating to NESLi2 in particular, in order to illuminate the options within Scotland. The origins of negotiations on electronic resource provision within Scotland are described, drawing on developments in other countries including Ireland and Scandinavia. After initial setbacks, the implementation of the Scottish Higher Education Digital Library (SHEDL) from 2007 to 2009 is detailed. Current benefits arising from SHEDL are explained, and some possible future developments are discussed

SPIN-MIMS simplifying the SPIN-MAS instrumentation for online measurement of 15N-abundances of ammonium, nitrite and nitrate in aqueous solutions

Common methods for measuring selectively the 15N abundances in individual N-species such as NH4+, NO2- and NO3- in samples with multiple N-species are laborious and time consuming. The SPIN-MAS technique (Stange et al. 2007) offers an automated, rapid and selective determination of 15N abundances in NH4+, NO2- and NO3- in aqueous samples. During a SPIN-MAS measurement one of three different reaction solutions is mixed with the aqueous sample in a Sample Preparation unit for Inorganic N-species (SPIN). The reaction solution is chosen in dependence on the N-species of interest. The gaseous reaction products (N2 or NO) are then conducted to a quadrupole mass spectrometer (MAS) in a helium stream. This measurement technique is not commonly used due to its complex instrumentation. The instrumentation can be significantly simplified by the use of a membrane inlet mass spectrometer (MIMS). The presented SPIN-MIMS approach relies on the use of a reaction capillary in which the sample containing the N-species of interest is mixed with the corresponding reaction solution. The mixture of reaction solution and sample is pumped from the reaction capillary directly to the membrane inlet of the mass spectrometer. The reaction products (N2 or NO) formed during the reaction of NH4+, NO2- and NO3- with the reaction solutions are passed through the gas-permeable membrane of the inlet directly into the ion source of the mass spectrometer. 15N standards with different at% 15N (NH4+, NO2- and NO3- respectively in dist. Water) were used to assess the performance of the system. Overall, SPIN-MIMS measurements showed a good agreement between measured and expected 15N abundances (range 0.36 – 10 at% 15N deviations: <0.5 at% 15N for NH4+-, <0.23 for NO2-- and <0.15 at% 15N for NO3-- standards)