Simulation of PET bottle rinsing

In dieser Arbeit wurden Computersimulationen zu diversen Rinsprozessen entwickelt, durchgeführt und analysiert. Die Computersimulationen basieren auf einer turbulenten Zweiphasenströmung (Wasser und Luft), die mittels Methoden der Numerischen Strömungsmechanik (Finite-Volumen-Verfahren) berechnet wurden; die Berechnungen wurden mit dem Open-Source-Code OpenFOAM durchgeführt. Das mathematische Modell kann auf verschiedene Flaschen- und Düsentypen angewandt werden - im Rahmen dieser Arbeit wurde der Flaschentyp (0,5 L-PET-Flasche) konstant gehalten, während der Düsentyp variiert wurde. Mittels experimenteller Daten, die zuvor am Teststand gemessen wurden, wurde das zugrundeliegende mathematische Modell validiert. Die Validierung umfasste dabei zwei spezifische Eigenschaften: zum einen die Erfassung des zeitlichen Verlaufs und Charakters des Rinsprozesses und zum anderen die Verteilungscharakteristik der hydrodynamischen Kräfte entlang der Flaschenwand. Ersteres wurde durch Experimente mit einer High-Speed Videokamera erreicht, letzteres durch die Durchführung von sog. Senf-Ethanol-Experimenten. Das Senf-Ethanol-Experiment besteht darin, eine Flasche, deren Flaschenwand mit einer Senf-Ethanol-Mischung benetzt ist, auszuspülen; dabei korreliert das Maß, in dem die Senfschicht abgetragen wird, mit den angreifenden hydrodynamischen Kräften über einen bestimmten Zeitraum. Basierend auf den Computersimulationen wurden die jeweiligen Rinsszenarien auf hygienerelevante Kenngrößen hin untersucht. Diese Merkmale sind in der vorliegenden Arbeit spezifiziert als Reinigungseffizienz, Benetzungsgrad und Dauer der Entleerung. Als Reinigungseffizienz wird hier das zeitliche Integral über die Wandschubspannungen definiert. Sowohl Reinigungseffizienz als auch Benetzungsgrad werden dazu durch sog. Reinigungskarten entlang der Flaschenwand dargestellt. Dadurch erhält der Ingenieur neben der Visualisierung des Merkmals auch eine gute räumliche Darstellung von dessen lokaler Ausprägung. Zur Darstellung der Flaschenentleerung werden sog. Massenverlaufsdiagramme herangezogen, welche die Wassermassen als Funktion der Zeit grafisch darstellen. Basierend auf den zuvor beschriebenen Ergebnissen lassen sich schließlich Reinigungsdefizite aufdecken, die Aufschluss über die weitergehende Optimierung der Düsenstruktur geben.In this study, computer simulations for bottle rinsing processes were developed, carried out and analyzed. The simulations are based on a two-phase turbulent model (water and air); the computations were carried out using a finite volume method provided by OpenFOAM software. The mathematical model can be applied to different kinds of bottle and nozzle types. However, in the framework of this study a 0.5 L PET bottle was used while the nozzle type was varied. To determine the accuracy of the mathematical model, it was validated by experimental data which were measured in a laboratory using test rig. The validation approach involved the investigation of two specific properties: (i) the characterization of temporal events and (ii) the characteristic distribution of the hydrodynamic forces during rinsing. The former was carried out using a high-speed video camcorder, the latter by a so-called mustard-ethanol-experiment. The mustard-ethanol experiment consists of rinsing a bottle which is uniformly coated with mustard-ethanol on its inner surface; the mustard is then removed according to the effectiveness of the hydrodynamic forces over a specific time range. Based on computed data, the respective rinsing scenarios were investigated in terms of cleaning characteristics such as cleaning effectiveness, water coverage and emptying time. Cleaning effectiveness is understood as the temporal integrated wall shear stresses. Both cleaning effect and water coverage are depicted through bottle maps. Thereby the engineer obtains not only a visualization of the particular characteristic, but also an illustration of its spatial distribution. The emptying process is depicted by so-called water mass history diagrams showing the amount of water within the bottle as a function of time

Endothelial LRP1 transports amyloid-β1-42 across the blood-brain barrier

According to the neurovascular hypothesis, impairment of low-density lipoprotein receptor-related protein-1 (LRP1) in brain capillaries of the blood-brain barrier (BBB) contributes to neurotoxic amyloid-beta (A beta) brain accumulation and drives Alzheimer's disease (AD) pathology. However, due to conflicting reports on the involvement of LRP1 in A beta transport and the expression of LRP1 in brain endothelium, the role of LRP1 at the BBB is uncertain. As global Lrp1 deletion in mice is lethal, appropriate models to study the function of LRP1 are lacking. Moreover, the relevance of systemic A beta clearance to AD pathology remains unclear, as no BBB-specific knockout models have been available. Here, we developed transgenic mouse strains that allow for tamoxifen-inducible deletion of Lrp1 specifically within brain endothelial cells (Slo1c1-CreER(Tz) Lrp1(fl/fl) mice) and used these mice to accurately evaluate LRP1-mediated A beta BBB clearance in vivo. Selective deletion of Lrp1 in the brain endothelium of C57BL/6 mice strongly reduced brain efflux of injected [I-125] A beta(1-42). Additionally, in the 5xFAD mouse model of AD, brain endothelial-specific Lrp1 deletion reduced plasma A beta levels and elevated soluble brain A beta, leading to aggravated spatial learning and memory deficits, thus emphasizing the importance of systemic AD elimination via the BBB. Together, our results suggest that receptor-mediated A beta BBB clearance may be a potential target for treatment and prevention of A beta brain accumulation in AD

The Bose-Einstein Condensate and Cold Atom Laboratory

© 2020, The Author(s). Microgravity eases several constraints limiting experiments with ultracold and condensed atoms on ground. It enables extended times of flight without suspension and eliminates the gravitational sag for trapped atoms. These advantages motivated numerous initiatives to adapt and operate experimental setups on microgravity platforms. We describe the design of the payload, motivations for design choices, and capabilities of the Bose-Einstein Condensate and Cold Atom Laboratory (BECCAL), a NASA-DLR collaboration. BECCAL builds on the heritage of previous devices operated in microgravity, features rubidium and potassium, multiple options for magnetic and optical trapping, different methods for coherent manipulation, and will offer new perspectives for experiments on quantum optics, atom optics, and atom interferometry in the unique microgravity environment on board the International Space Station

Microgravity facilities for cold atom experiments

Microgravity platforms enable cold atom research beyond experiments in typical laboratories by removing restrictions due to the gravitational acceleration or compensation techniques. While research in space allows for undisturbed experimentation, technological readiness, availability and accessibility present challenges for experimental operation. In this work we focus on the main capabilities and unique features of ground-based microgravity facilities for cold atom research. A selection of current and future scientific opportunities and their high demands on the microgravity environment are presented, and some relevant ground-based facilities are discussed and compared. Specifically, we point out the applicable free fall times, repetition rates, stability and payload capabilities, as well as programmatic and operational aspects of these facilities. These are contrasted with the requirements of various cold atom experiments. Besides being an accelerator for technology development, ground-based microgravity facilities allow fundamental and applied research with the additional benefit of enabling hands-on access to the experiment for modifications and adjustments

Systemic multicompartmental effects of the gut microbiome on mouse metabolic phenotypes

To characterize the impact of gut microbiota on host metabolism, we investigated the multicompartmental metabolic profiles of a conventional mouse strain (C3H/HeJ) (n=5) and its germ-free (GF) equivalent (n=5). We confirm that the microbiome strongly impacts on the metabolism of bile acids through the enterohepatic cycle and gut metabolism (higher levels of phosphocholine and glycine in GF liver and marked higher levels of bile acids in three gut compartments). Furthermore we demonstrate that (1) well-defined metabolic differences exist in all examined compartments between the metabotypes of GF and conventional mice: bacterial co-metabolic products such as hippurate (urine) and 5-aminovalerate (colon epithelium) were found at reduced concentrations, whereas raffinose was only detected in GF colonic profiles. (2) The microbiome also influences kidney homeostasis with elevated levels of key cell volume regulators (betaine, choline, myo-inositol and so on) observed in GF kidneys. (3) Gut microbiota modulate metabotype expression at both local (gut) and global (biofluids, kidney, liver) system levels and hence influence the responses to a variety of dietary modulation and drug exposures relevant to personalized health-care investigations

NMR-based metabolic characterization of chicken tissues and biofluids: a model for avian research

Introduction Poultry is one of the most consumed meat in the world and its related industry is always looking for ways to improve animal welfare and productivity. It is therefore essential to understand the metabolic response of the chicken to new feed formulas, various supplements, infections and treatments. Objectives As a basis for future research investigating the impact of diet and infections on chicken’s metabolism, we established a high-resolution proton nuclear magnetic resonance (NMR)-based metabolic atlas of the healthy chicken (Gallus gallus). Methods Metabolic extractions were performed prior to 1H-NMR and 2D NMR spectra acquisition on twelve biological matrices: liver, kidney, spleen, plasma, egg yolk and white, colon, caecum, faecal water, ileum, pectoral muscle and brain of 6 chickens. Metabolic profiles were then exhaustively characterized. Results Nearly 80 metabolites were identified. A cross-comparison of these matrices was performed to determine metabolic variations between and within each section and highlighted that only eight core metabolites were systematically found in every matrice. Conclusion This work constitutes a database for future NMR-based metabolomic investigations in relation to avian production and health

Modeling spinal muscular atrophy in Drosophila links Smn to FGF signaling

FGF signaling in neurons is regulated by Survival Motor Neuron, a component of a complex that regulates snRNP biogenesis and FGF receptor expression

Program FFlexCom — High frequency flexible bendable electronics for wireless communication systems

Today, electronics are implemented on rigid substrates. However, many objects in daily-life are not rigid — they are bendable, stretchable and even foldable. Examples are paper, tapes, our body, our skin and textiles. Until today there is a big gap between electronics and bendable daily-life items. Concerning this matter, the DFG Priority Program FFlexCom aims at paving the way for a novel research area: Wireless communication systems fully integrated on an ultra-thin, bendable and flexible piece of plastic or paper. The Program encompasses 13 projects led by 25 professors. By flexibility we refer to mechanical flexibility, which can come in flavors of bendability, foldability and, stretchability. In the last years the speed of flexible devices has massively been improved. However, to enable functional flexible systems and operation frequencies up to the sub-GHz range, the speed of flexible devices must still be increased by several orders of magnitude requiring novel system and circuit architectures, component concepts, technologies and materials