Wireless power transfer systems can be utilized to advance electromobility, especially in local public transport. These systems emanate low-frequency stray magnetic fields that expose living beings ...in the vicinity and induce potentially harmful electric fields into the exposed biological tissues. To ensure personal protection, ICNIRP has established basic restrictions on the body-internal electric field strength that should not be exceeded. Since this field strength cannot be measured, numerical schemes such as the Scalar-Potential Finite Difference scheme need to be utilized to determine the induced body-internal electric field distribution. This numerical scheme allows a near real-time body-internal electric field determination but requires as input a fine sampling of the magnetic flux distribution in the domain of potential human exposure. The works' objective is to provide a component for deriving the large number of required magnetic flux densities from free-space field measurements in near real-time, required for direct body-internal electric field determinations in real exposure assessment environments. By applying a highly parallelized approximation procedure using radial basis functions on NVIDIA GPUs, the required magnetic flux densities for different human voxel models with an ICNIRP-recommended edge length of 2 mm can be derived in a few milliseconds.
Accurate citation practices are important to ensure a robust knowledge base and overall trustworthy academic enterprise. The prevalence of poor citation practices has been assessed in multiple ...fields, resulting in estimates of inaccurate citations ranging typically between 15% and 25%. Here, we assessed the accuracy of citations in research articles extracted from 11 journals with a polar sciences focus. Thirty percent of citations from recent articles (published between 2018 and 2019) and 26 % of citations between 1980 and 2019 were found to be inaccurate. We found no evidence for differences in citation accuracy between the journals assessed, or effects on citation accuracy associated with the number of authors, number of references, position of references or if a citation was a self-citation or not. Importantly, we present evidence for a decline in citation accuracy between 1980 and 2019 in polar sciences. Citation practices are unlikely to improve unless journals provide incentives for scholars to be more meticulous, and we recommend active monitoring of citation accuracy and citation appropriateness by reviewers and editorial staff.
The impacts of ecosystem engineers may be expected to vary along environmental gradients. Due to some resources being more limited in arid than in mesic environments, disturbances created by ...burrowing mammals are expected to have a greater ameliorating effect in arid environments, with larger differences in microhabitat conditions expected between burrows and undisturbed areas. The aim of this study was to test if the impacts of a medium-sized burrowing mammal, the aardvark, on soil properties (soil temperature, moisture and compaction) and vegetation characteristics (plant cover, species richness and species composition) are consistent across three biomes that differ strongly in annual rainfall. Burrowing affected soil and vegetation attributes, but the direction and magnitude of these biogeomorphological impacts were not consistent across the different biomes. For example, plant species composition was altered by burrowing in the arid scrubland and in the mesic grassland, but not in the semi-arid savannah. Contrary to expectations, the difference in the impacts of burrowing between biomes were not related to rainfall, with burrowing having strong, albeit different, impacts in both the arid scrubland and the mesic grassland, but weaker effects in the semi-arid savannah. It appears, therefore, that the impacts of these biogeomorphic agents may be site-specific and that it may be difficult to predict variation in their biotic and abiotic effects across environmental gradients. As a result, forecasting the impacts of ecosystem engineers under different conditions remains a challenge to management, restoration and conservation strategies related to these types of species.
The KArlsruhe TRItium Neutrino (KATRIN) experiment will measure the mass of the neutrino with a sensitivity of 0.2 eV (90 % CL). The Forward Beam Monitor (FBM) is a monitoring system which comprises ...of a complex mechanical setup capable of inserting a detector board into the KATRIN beamline at the end of the source and transport section. The detector board contains a Hall sensor, a temperature gauge, and two PIN diodes which can detect electrons from the source with a precision of 0.1 % in less than a minute within an electron flux density of 106 s−1mm−2.
Wetlands form part of a diverse range of habitats and play an important role in the ecology and hydrological cycle but are amongst the most threatened ecological systems. It is therefore critical to ...understand the hydrology of wetlands, and their contributing water sources in particular, to ensure appropriate management of these systems. Land use activities not only alter the runoff characteristics of catchments, but also often result in modified flow regimes in watercourses. Wetlands often develop accidentally in anthropogenic landscapes and are not uncommon. However, these wetlands are poorly documented and researched. An accidental wetland formed in the Kgaswane Mountain Reserve, Rustenburg, due to leaking water infrastructure. The aim of this project was to categorise the wetland and confirm its origin, focussing on the role of the leakage. Methods included hydrogeomorphic classification, water ion composition analysis, as well as infield temperature and electrical conductivity measurements. Historical satellite imagery was used to study the evolution of the wetland over time. The electrical conductivity and ionic composition results suggest an unnatural water source, providing support that a leaking pipe caused the wetland to form. Management of accidental wetlands is discussed and the potential for future, related research is contemplated.
Positive plant interactions, such as those associated with nurse plants, have been suggested to dominate over negative interactions in environments with high abiotic stress. Here we demonstrate that ...the sub-Antarctic cushion plant species,
Azorella selago (Apiaceae), positively affects the distribution of both its own seedlings and those of the perennial grass,
Agrostis magellanica (Poaceae). As a result of the light weight and small size of seeds of both species, coupled with strong winds experienced in the study area, we consider it unlikely that these patterns are the result of very localized seed dispersal from the study cushions themselves. Instead, we suggest that both cushions and rocks act as seed traps, trapping seeds dispersed by wind, runoff and/or downslope sediment transport through frost creep. In addition, increased
A. selago seedling numbers around cushions, but not around rocks, suggest that cushions provide a biological nurse effect, such as improving soil nutrient status or providing mychorrizae, to seedlings of their own kind.
On sub-Antarctic Marion Island cushions of the dominant vascular plant species,
Azorella selago, interact with the geomorphology of fellfield landscapes by affecting sediment distribution and ...ultimately terrace formation. Here, to understand the consequences of
Azorella cushions for substrate movement and sorting, we quantified the size and shape of
Azorella cushions and the grain size distribution of sediment surrounding these cushions, using a combination of image analysis approaches. Results show that as cushions become larger, they tend to become more elongated and grow more perpendicular to the slope. Mean and variance of grain size were greater upslope of
Azorella cushions, while the number of particles was higher downslope of cushions, although these differences were not significant at all sites studied. Differences between upslope and downslope particle sizes were, however, not related to cushion elongation or growth angle as had been expected. The observed sediment partitioning is likely caused by a combination of frost-related sediment transport and
Azorella cushions acting as sediment obstructions. Understanding these interactions between
Azorella cushions and the landscape is especially important in the light of recent warming and drying on the island, as particle size affects soil properties such as water-holding capacity and frost susceptibility.
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