82 research outputs found
Global detection and analysis of coastline associated rainfall using an objective pattern recognition technique
Coastally associated rainfall is a common feature especially in tropical and
subtropical regions. However, it has been difficult to quantify the
contribution of coastal rainfall features to the overall local rainfall. We
develop a novel technique to objectively identify precipitation associated with
land-sea interaction and apply it to satellite based rainfall estimates. The
Maritime Continent, the Bight of Panama, Madagascar and the Mediterranean are
found to be regions where land-sea interactions plays a crucial role in the
formation of precipitation. In these regions 40% to 60% of the total
rainfall can be related to coastline effects. Due to its importance for the
climate system, the Maritime Continent is a particular region of interest with
high overall amounts of rainfall and large fractions resulting from land-sea
interactions throughout the year. To demonstrate the utility of our
identification method we investigate the influence of several modes of
variability, such as the Madden-Julian-Oscillation and the El Ni\~no Southern
Oscillation, on coastal rainfall behavior. The results suggest that during
large scale suppressed convective conditions coastal effects tend modulate the
rainfall over the Maritime Continent leading to enhanced rainfall over land
regions compared to the surrounding oceans. We propose that the novel objective
dataset of coastally influenced precipitation can be used in a variety of ways,
such as to inform cumulus parametrization or as an additional tool for
evaluating the simulation of coastal precipitation within weather and climate
models
Quantification of specific bindings of biomolecules by magnetorelaxometry
The binding reaction of the biomolecules streptavidin and anti-biotin antibody, both labelled by magnetic nanoparticles (MNP), to biotin coated on agarose beads, was quantified by magnetorelaxometry (MRX). Highly sensitive SQUID-based MRX revealed the immobilization of the MNP caused by the biotin-streptavidin coupling. We found that about 85% of streptavidin-functionalised MNP bound specifically to biotin-agarose beads. On the other hand only 20% of antibiotin-antibody functionalised MNP were specifically bound. Variation of the suspension medium revealed in comparison to phosphate buffer with 0.1% bovine serum albumin a slight change of the binding behaviour in human serum, probably due to the presence of functioning (non heated) serum proteins. Furthermore, in human serum an additional non-specific binding occurs, being independent from the serum protein functionality
Coastal Tropical Convection in a Stochastic Modeling Framework
Recent research has suggested that the overall dependence of convection near
coasts on large-scale atmospheric conditions is weaker than over the open ocean
or inland areas. This is due to the fact that in coastal regions convection is
often supported by meso-scale land-sea interactions and the topography of
coastal areas. As these effects are not resolved and not included in standard
cumulus parametrization schemes, coastal convection is among the most poorly
simulated phenomena in global models. To outline a possible parametrization
framework for coastal convection we develop an idealized modeling approach and
test its ability to capture the main characteristics of coastal convection. The
new approach first develops a decision algorithm, or trigger function, for the
existence of coastal convection. The function is then applied in a stochastic
cloud model to increase the occurrence probability of deep convection when
land-sea interactions are diagnosed to be important. The results suggest that
the combination of the trigger function with a stochastic model is able to
capture the occurrence of deep convection in atmospheric conditions often found
for coastal convection. When coastal effects are deemed to be present the
spatial and temporal organization of clouds that has been documented form
observations is well captured by the model. The presented modeling approach has
therefore potential to improve the representation of clouds and convection in
global numerical weather forecasting and climate models.Comment: Manuscript submitted for publication in Journal of Advances in
Modeling Earth System
Magnetic nanoparticles interact and pass an in vitro co-culture blood-placenta barrier model
Magnetic nanoparticles are interesting tools for biomedicine. Before application, critical prerequisites have to be fulfilled. An important issue is the contact and interaction with biological barriers such as the blood-placenta barrier. In order to study these processes in detail, suitable in vitro models are needed. For that purpose a blood-placenta barrier model based on the trophoblast-like cell line BeWo and primary placenta-derived pericytes was established. This model was characterized by molecular permeability, transepithelial electrical resistance and cell-cell-contact markers. Superparamagnetic iron oxide nanoparticles (SPIONs) with cationic, anionic or neutral surface charge were applied. The localization of the nanoparticles within the cells was illustrated by histochemistry. The time-dependent passage of the nanoparticles through the BeWo/pericyte barrier was measured by magnetic particle spectroscopy and atomic absorption spectroscopy. Cationically coated SPIONs exhibited the most extensive interaction with the BeWo cells and remained primarily in the BeWo/pericyte cell layer. In contrast, SPIONs with neutral and anionic surface charge were able to pass the cell layer to a higher extent and could be detected beyond the barrier after 24 h. This study showed that the mode of SPION interaction with and passage through the in vitro blood-placenta barrier model depends on the surface charge and the duration of treatmen
Lithium in Europa
Aktuell ist die deutsche Industrie vollständig auf den Import von Metallen angewiesen, so auch für das leichteste Metall – Lithium. Die globale Produktion von Lithium ist in den letzten fünf Jahren um 263 % gestiegen, die Bergbauförderung liegt bei ca. 100 kt LCE1 (Stand 2021). Der Bedarf des Metalls für Batterien könnte 2030 laut der EU allein in Europa bei ca. 325 kt LCE liegen. Um diesen Bedarf des Marktes mit zu decken, werden in Europa derzeit verschiedene Lithiumprojekte entwickelt. Diese sehen eine Förderung von Lithium aus konventionellen, magmatischen oder sedimentären Gesteinen sowie unkonventionellen geothermalen Solen vor. Acht dieser Projekte befinden sich in einem fortgeschrittenen Entwicklungsstadium und könnten 2030 dazu beitragen, dass zwischen 40 % und 55 % des Bedarfs an Lithium aus europäischen Lagerstätten gewonnen werden könnten. Außerdem wird an Fördermethoden und Aufbereitungstechnologien geforscht, wie beispielsweise die Lithiumgewinnung aus Grubenwasser ehemaliger Bergwerke oder Produktionswässern aus Erdgas- oder Erdölförderungen. Die Entwickler der Lithiumprojekte in Europa erfahren neben technischen, wirtschaftlichen und genehmigungsrechtlichen Herausforderungen auch Ablehnung durch Bürgerinitiativen. Das Recycling von Lithium, speziell aus Lithiumionenbatterien wird in Deutschland durch verschiedene Förderprogramme des Bundes unterstützt und dadurch wissenschaftlich und technisch vorangetrieben. Dies soll dazu beitragen, dass die Quotenvorgaben für Rezyklate aus einem zukünftigen Rücklauf von Batterien erfüllt werden können. Ohne den nationalen und internationalen Bergbau unter der Beibehaltung und weiteren Etablierung von Umwelt- und Sozialstandards, die weitere Entwicklung von Bergbautechnologien sowie den Ausbau der Recyclingmöglichkeiten wird der Lithiumbedarf in Europa nicht zu decken sein
A Theory of Multidimensional Information Disclosure
We study disclosure of information about the multidimensional state of the world when uninformed receivers' actions affect the sender's utility. Given a disclosure rule, the receivers form an expectation about the state following each message. Under the assumption that the sender's expected utility is written as the expected value of a quadratic function of those conditional expectations, we identify conditions under which full and no disclosure is optimal for the sender and show that a linear transformation of the state is optimal if it is normally distributed. We apply our theory to advertising, political campaigning, and monetary policy.The 14th ISER-Moriguchi Prize (2011) Awarded Paper
Public Policy and Venture Capital Backed Innovation
This paper discusses the role of public policy towards the venture capital industry. The model emphasizes four margins: supply of entrepreneurs due to career choice, entry of venture capital funds and search for investment opportunities, entrepreneurial effort and venture capital advice during the start-up period, and introduction of new goods by successful start-ups. The paper considers short- and long-run comparative static and welfare effects of policy reform with regard to capital gains taxation, innovation subsidies, public R&D spending and other policy initiatives
Crystallization age of alpine cleft monazite-(Ce) and correlation with tectonically driven hydrothermal dissolution/precipitation events
Hydrothermal monazite-(Ce) from open clefts/fissure veins in the Alps was utilized as a complimentary tool for dating brittle-ductile/brittle deformation. It may preserve evidence of several crystallization events, commonly over 4-7 Ma, up to ~20 Ma. Monazite-(Ce) crystallizes within ~350-200 °C during tectonic and/or fluid flux events disequilibrating the fluid-crystal/rock chemistry within a cleft. It resists alteration/diffusion under prevailing p-T conditions, but may experience new/re-crystallization or dissolution-reprecipitation. Ages from the northeastern Alps, Austria, of 90-70 Ma cover near peak metamorphism during Eo-Alpine collision over orogenic collapse to extension. In the eastern Tauern Window, ages date metamorphic dome exhumation during Alpine collision at ~19-15 Ma. In the Lepontine dome area ages of ~19-5 Ma date early exhumation, doming and a later change after 12 Ma from thrusting to strike-slip movements, linked to a progressive concentration of deformation towards the extended Rhone-Simplon/Penninic Front fault system in the Mont-Blanc/Aiguilles-Rouges, Aar and western Lepontine areas
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