26 research outputs found
Spin quadrupoletronics: moving spin anisotropy around
We show that spin anisotropy can be transferred to an isotropic system by
transport of spin quadrupole moment. We derive the quadrupole moment current
and continuity equation and study a high-spin valve structure consisting of two
ferromagnets coupled to a quantum dot probing an impurity spin. The quadrupole
back-action on their coupled spin results in spin torques and anisotropic spin
relaxation which do not follow from standard spin current considerations. We
demonstrate the detection of the impurity spin by charge transport and its
manipulation by electric fields.Comment: v2 updated arXiv reference [6
Inhalation exposure to hazardous substances during powder-bed processes
This work resumes first results concerning the identification of workers' inhalation exposure by means of workplace measurements in the field of additive manufacturing. In particular for powder-bed processes, risks caused by mixed exposures due to released particles and relevant chemical constituents or possible volatile compounds have to be evaluated. The workplace measurements are focused on processes in the automotive as well as the aviation and tool construction industry. The aim is to gain exposure data concerning the application of metal-containing powders and alloys as well as polymer powders in powder-bed processes and to derive instructions for good working practice
Spintronic magnetic anisotropy
An attractive feature of magnetic adatoms and molecules for nanoscale
applications is their superparamagnetism, the preferred alignment of their spin
along an easy axis preventing undesired spin reversal. The underlying magnetic
anisotropy barrier --a quadrupolar energy splitting-- is internally generated
by spin-orbit interaction and can nowadays be probed by electronic transport.
Here we predict that in a much broader class of quantum-dot systems with spin
larger than one-half, superparamagnetism may arise without spin-orbit
interaction: by attaching ferromagnets a spintronic exchange field of
quadrupolar nature is generated locally. It can be observed in conductance
measurements and surprisingly leads to enhanced spin filtering even in a state
with zero average spin. Analogously to the spintronic dipolar exchange field,
responsible for a local spin torque, the effect is susceptible to electric
control and increases with tunnel coupling as well as with spin polarization.Comment: 6 pages with 4 figures + 26 pages of Supplementary Informatio
Generic pregabalin : current situation and implications for health authorities, generics and biosimilars manufacturers in the future
The manufacturer of pregabalin has a second use patent covering prescribing for neuropathic pain: its principal indication. The manufacturer has threatened legal action in the UK if generic pregabalin rather than Lyrica is prescribed for this indication. No problems exist for practitioners who prescribe pregabalin for epilepsy or generalized anxiety disorder. This has serious implications for health authorities. In Germany, however, generics could be legally prescribed for any approved indication once one indication loses its patent. We aim to establish the current situation with pregabalin among principally European countries. Personnel from 33 regional and national health authorities mainly from Europe, and nine from universities across Europe working as advisers to health authorities or with insight into their activities, were surveyed regarding four specific questions via email to shed light on the current situation with Lyrica and pregabalin in their country. The information collated from each country was subsequently checked for accuracy with each co-author by email and face-to-face contact and collated into five tables. The scenarios ranged from extending the patent life of Lyrica (e.g. France), endorsing the prescribing of Lyrica for neuropathic pain (e.g. Catalonia and South Korea), and current prescribing of pregabablin for all indications (e.g. Serbia and Germany). Little activity has taken place in European countries in which generic pregabalin is not yet reimbursed. The availability of generic pregabalin has prompted a number of different activities to be undertaken among the 33 countries and regions surveyed. The situation in Serbia and the historic situation in Germany provide examples of ways to maximize savings once a product loses its patent for at least one indication
About war, about hearts and about loneliness : a study on documentary in videogames and the transformation of an art form
Diese Arbeit sucht nach einer Verbindung zwischen Dokumentarfilm und Videospiel, und sucht dabei nach mehr als nur Geschichte in Videospielen. Videospiele nutzen eine eigene Form der Erzählung von Geschichten. Die Spiele Valiant Hearts, This War of Mine und Never alone werden auf dokumentarische Erzählformen untersucht. Außerdem wird basierend auf den Untersuchungen ein eigenes Spielkonzept für ein dokumentarisches Spiel präsentiert
Elementary Reactions of Energy-Selected Fluoroethene and 1,1-Difluoroethene Ions. 2. The Kinetics of HF-Loss
Detecting Groundwater Temperature Shifts of a Subsurface Urban Heat Island in SE Germany
The subsurface beneath cities commonly shows a temperature anomaly, a so-called Subsurface Urban Heat Island (SUHI), due to anthropogenic heat input. This excess heat has multiple effects on groundwater and energy resources, such as groundwater chemistry or the efficiency of geothermal systems, which makes it necessary to investigate the temporal development of a SUHI. For this purpose, temperature profiles of 38 observation wells in the German city of Nuremberg were evaluated from 2015 to 2020 and the measured temperature changes were linked to the surface sealing. The results show that the groundwater temperatures changed between −0.02 K/a and +0.21 K/a, on average by +0.07 K/a during this period. A dependence between the temperature increase and the degree of sealing of the land surface was also observed. In areas with low surface sealing of up to 30% the warming amounts were 0.03 K/a on average, whereas in areas with high sealing of over 60% significantly higher temperature increases of 0.08 K/a on average were found. The results clearly emphasize that the subsurface urban heat island in its current state does not represent a completed process, but that more heat energy continues to enter the subsoil within the city than is the case with near-natural land surfaces
Calculating Energy and Its Spatial Distribution for a Subsurface Urban Heat Island Using a GIS-Approach
In urban areas, the human influence on the city-ecosystem often results in a Subsurface Urban Heat Island (SUHI), which can be used geothermally. Unfortunately, a model of a SUHI does not consider the geology and hydrogeology of the subsoil. These can vary significantly over short distances, and are of considerable importance for the energy balance. In this work, we calculated the energy and its density stored in the subsoil via a SUHI. For this so-called energy-SUHI (e-SUHI), we evaluated the geology and its physical parameters for the first 20 m below ground level in the German city of Nuremberg and linked them to measured underground temperatures in a GIS application. This approach revealed stored energy of 1.634 × 1010 MJ within the soil and water for the study area with an area of 163 km2 and a volume of 3.26 × 109 m3. It corresponds to an average energy density of 5.0 MJ/m3. The highest energy density of 16.5 MJ/m3 was found in the city center area and correlated well to increases in subsurface temperature. As expected, our model reacts sensitively to thickness changes in the geological layers and the unsaturated zone
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Ubiquitin-dependent regulation of COPII coat size and function.
Packaging of proteins from the endoplasmic reticulum into COPII vesicles is essential for secretion. In cells, most COPII vesicles are approximately 60-80 nm in diameter, yet some must increase their size to accommodate 300-400 nm procollagen fibres or chylomicrons. Impaired COPII function results in collagen deposition defects, cranio-lenticulo-sutural dysplasia, or chylomicron retention disease, but mechanisms to enlarge COPII coats have remained elusive. Here, we identified the ubiquitin ligase CUL3-KLHL12 as a regulator of COPII coat formation. CUL3-KLHL12 catalyses the monoubiquitylation of the COPII-component SEC31 and drives the assembly of large COPII coats. As a result, ubiquitylation by CUL3-KLHL12 is essential for collagen export, yet less important for the transport of small cargo. We conclude that monoubiquitylation controls the size and function of a vesicle coat