Retrospektive Bestimmung der elektromagnetischen Exposition durch analoge Rundfunksender im Rahmen von KiSS

Im Rahmen einer epidemiologischen Fall-Kontroll-Studie zur Untersuchung eines möglichen Zusammenhangs zwischen der Häufigkeit kindlicher Leukämien und elektromagnetischer Strahlung (,,KiSS" – <b>Ki</b>ndliche Leukämien und Expositionen in der Umgebung von hochfrequenten <b>S</b>ende<b>s</b>tationen) soll die Exposition durch leistungsstarke analoge Rundfunksender retrospektiv (Zeitraum 1982–2003) quantifiziert werden. Die zu betrachtenden Sendernetze für AM-Hörfunk, FM-Hörfunk und analoges Fernsehen unterscheiden sich nicht nur hinsichtlich der Modulationsart und der von den Einzelsendern abgestrahlten Leistung, sondern auch in der Netzkonfiguration und den je nach Wellenbereich verschiedenen Strahlungseigenschaften der Sendeantennen. Damit sind bei diesen drei Rundfunkdiensten sowohl die absolute Größe als auch die räumliche Struktur der hervorgerufenen Exposition verschieden. Es wird dargelegt, wie die für die Prognose der Rundfunkversorgung verwendeten Rechenverfahren zur Modellierung der Feldstärke für die Modellierung der Exposition herangezogen und durch Kontrollmessungen validiert werden und wie trotz Wahrung der Vertraulichkeit der dabei unabdingbar zu verwendenden Senderbetriebsdaten eine unerwünschte Beeinflussung der Studienergebnisse durch die Senderbetreiber ausgeschlossen wird

Organizing Equity Exchanges

In the last years equity exchanges have diversified their operations into business areas such as derivatives trading, posttrading services, and software sales. Securities trading and post-trading are subject to economies of scale and scope. The integration of these functions into one institution ensures efficiency by economizing on transactions costs. Using balanced panel data from major equity exchanges over the period 2005-2007, we examine empirically the presence of economies of scale in securities trading. Moreover, we analyze the impact of vertical integration of trading, clearing, and settlement, the impact of the size of an exchange, and the impact of diversification on the profitability of exchanges. The evidence confirms that a large number of transactions leads to low costs per trade. The evidence shows that the profitability of equity exchanges is highest for vertically integrated exchanges and that diversification and size have a negative impact on their profitability

Time-Dependent Mechanical Response of a Composite PFSA Membrane

The mechanical response of a composite fuel cell membrane, made from layers of reinforced and unreinforced PFSA material, is investigated via both experimental and numerical means. First, the time-dependent mechanical properties for the reinforced layers are measured for a range of environmental and loading conditions. A three-network, viscoelastic-plastic constitutive model is developed to characterize the mechanical response of this reinforced membrane material. This constitutive model is then used in finite element simulations of a fuel cell unit (consisting of composite membrane, electrodes, gas diffusion layer and bipolar plates) where the effect of relative humidity (RH) cycling on the stress response of the composite membrane is investigated. Using numerical simulations, various layering configurations for the composite membrane and different load cases are studied. The investigation provides insight into the stress response of the membrane and suggests possible configurations that may improve the effective membrane life

Monte-Carlo Simulations of Radiation-Induced Activation in a Fast-Neutron and Gamma- Based Cargo Inspection System

An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron and gamma radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. The induced activity was determined by analyzing the gamma spectra. Based on the calculated radioactive inventory in the container, the dose levels due to the induced gamma radiation were calculated at several distances from the container and in relevant time windows after the irradiation, in order to evaluate the radiation exposure of the cargo handling staff, air crew and passengers during flight. The possibility of remanent long-lived radioactive inventory after cargo is delivered to the client is also of concern and was evaluated.Comment: Proceedings of FNDA 201

3D structure and formation of hydrothermal vent complexes at the Paleocene-Eocene transition, the Møre Basin, mid-Norwegian margin

Acknowledgments We thank Statoil for providing us with the PL251 (Tulipan) geophysical and geologic reports for well 6302/6- 1. We thank NORSAR for the free academic use of the SeisRox software during the modeling procedures and to Schlumberger for the free academic use of Petrel 2015. Spectral decomposition was carried out using FFA Geoteric software at the University of Aberdeen. FFA are thanked for donation of the software license to the University of Aberdeen. The authors further acknowledge the support from the Research Council of Norway through its Center of Excellence funding scheme, project 223272 (CEED), and from the MIMES project (grant no. 244155). We also gratefully acknowledge the support by the Faculty of Mathematics and Natural Sciences of the University of Oslo to TS. Clayton Grove and Craig Magee are thanked for their many insightful comments and suggestions that helped improve the paper substantially.Peer reviewedPublisher PD

Simple Viscous Flows: from Boundary Layers to the Renormalization Group

The seemingly simple problem of determining the drag on a body moving through a very viscous fluid has, for over 150 years, been a source of theoretical confusion, mathematical paradoxes, and experimental artifacts, primarily arising from the complex boundary layer structure of the flow near the body and at infinity. We review the extensive experimental and theoretical literature on this problem, with special emphasis on the logical relationship between different approaches. The survey begins with the developments of matched asymptotic expansions, and concludes with a discussion of perturbative renormalization group techniques, adapted from quantum field theory to differential equations. The renormalization group calculations lead to a new prediction for the drag coefficient, one which can both reproduce and surpass the results of matched asymptotics

COVID-19 genetic risk variants are associated with expression of multiple genes in diverse immune cell types

ABSTRACTCommon genetic polymorphisms associated with severity of COVID-19 illness can be utilized for discovering molecular pathways and cell types driving disease pathogenesis. Here, we assessed the effects of 679 COVID-19-risk variants on gene expression in a wide-range of immune cell types. Severe COVID-19-risk variants were significantly associated with the expression of 11 protein-coding genes, and overlapped with either target gene promoter or cis-regulatory regions that interact with target promoters in the cell types where their effects are most prominent. For example, we identified that the association between variants in the 3p21.31 risk locus and the expression of CCR2 in classical monocytes is likely mediated through an active cis-regulatory region that interacted with CCR2 promoter specifically in monocytes. The expression of several other genes showed prominent genotype-dependent effects in non-classical monocytes, NK cells, B cells, or specific T cell subtypes, highlighting the potential of COVID-19 genetic risk variants to impact the function of diverse immune cell types and influence severe disease manifestations.</jats:p

Kinetic modelling of competition and depletion of shared miRNAs by competing endogenous RNAs

Non-conding RNAs play a key role in the post-transcriptional regulation of mRNA translation and turnover in eukaryotes. miRNAs, in particular, interact with their target RNAs through protein-mediated, sequence-specific binding, giving rise to extended and highly heterogeneous miRNA-RNA interaction networks. Within such networks, competition to bind miRNAs can generate an effective positive coupling between their targets. Competing endogenous RNAs (ceRNAs) can in turn regulate each other through miRNA-mediated crosstalk. Albeit potentially weak, ceRNA interactions can occur both dynamically, affecting e.g. the regulatory clock, and at stationarity, in which case ceRNA networks as a whole can be implicated in the composition of the cell's proteome. Many features of ceRNA interactions, including the conditions under which they become significant, can be unraveled by mathematical and in silico models. We review the understanding of the ceRNA effect obtained within such frameworks, focusing on the methods employed to quantify it, its role in the processing of gene expression noise, and how network topology can determine its reach.Comment: review article, 29 pages, 7 figure

Case studies of capacity building for biodiversity monitoring

Monitoring the status and trends of species is critical to their conservation and management. However, the current state of biodiversity monitoring is insufficient to detect such for most species and habitats, other than in a few localised areas. One of the biggest obstacles to adequate monitoring is the lack of local capacity to carry out such programs. Thus, building the capacity to do such monitoring is imperative. We here highlight different biodiversity monitoring efforts to illustrate how capacity building efforts are being conducted at different geographic scales and under a range of resource, literacy, and training constraints. Accordingly, we include examples of monitoring efforts from within countries (Kenya, France, and China), within regions (Central America and the Arctic) and larger capacity building programs including EDGE (Evolutionarily Distinct and Globally Endangered) of Existence and the National Red List Alliance