Cosmic-ray propagation around the Sun: investigating the influence of the solar magnetic field on the cosmic-ray Sun shadow

The cosmic-ray Sun shadow, which is caused by high-energy charged cosmic rays being blocked and deflected by the Sun and its magnetic field, has been observed by various experiments, such as Argo-YBJ, HAWC, Tibet, and IceCube. Most notably, the shadow's size and depth was recently shown to correlate with the 11-year solar cycle. The interpretation of such measurements, which help to bridge the gap between solar physics and high-energy particle astrophysics, requires a solid theoretical understanding of cosmic-ray propagation in the coronal magnetic field. It is the aim of this paper to establish theoretical predictions for the cosmic-ray Sun shadow in order to identify observables that can be used to study this link in more detail. To determine the cosmic-ray Sun shadow, we numerically compute trajectories of charged cosmic rays in the energy range of 5-316 TeV for five different mass numbers. We present and analyze the resulting shadow images for protons and iron, as well as for typically measured cosmic-ray compositions. We confirm the observationally established correlation between the magnitude of the shadowing effect and both the mean sunspot number and the polarity of the magnetic field during the solar cycle. We also show that during low solar activity, the Sun's shadow behaves similarly to that of a dipole, for which we find a non-monotonous dependence on energy. In particular, the shadow can become significantly more pronounced than the geometrical disk expected for a totally unmagnetized Sun. For times of high solar activity, we instead predict the shadow to depend monotonously on energy, and to be generally weaker than the geometrical shadow for all tested energies. These effects should become visible in energy-resolved measurements of the Sun shadow, and may in the future become an independent measure for the level of disorder in the solar magnetic field.Comment: 18 pages, 88 figure

Mehrfachförderkulisse Stadtzentrum - ein Puzzle für die Zentrenentwicklung? : Das Zusammenwirken von Städtebauförderprogrammen in städtischen Zentren am Beispiel des „Aktiven Stadtzentrums Turmstraße“ in Berlin Moabit

In den Zentren vieler Städte und Gemeinden mehren sich die Probleme. Betroffene Zentren verlieren an Attraktivität und Bedeutung, an Funktions- und Nutzungsvielfalt sowie sozialer Kohäsionskraft. Ursachen liegen in strukturellen Veränderungen des Einzelhandels, im Wandel des Einkaufs- und Freizeitverhaltens, aber auch in städtebaulichen und sozialräumlichen Problemen der umgebenden Stadtteile und Quartiere. Die notwendige Stabilisierung und Stärkung der Zentren - als Rückgrat der Innenstädte und Quartiere - ist allerdings vor dem Hintergrund der Komplexität der Aufgabe und der knappen finanziellen Ressourcen der Kommunen eine Herausforderung für die Stadtentwicklung. Eine besondere Bedeutung kommt daher der Städtebauförderung zu, die 2008 um die spezifische Programmlinie Aktive Stadt- und Ortsteilzentren ergänzt wurde. Das Programm ist allerdings hinsichtlich seiner Interventionsmöglichkeiten und seiner Laufzeit begrenzt. In der vorliegenden Diplomarbeit werden die auf Zentren wirkenden Rahmenbedingungen untersucht und auf dieser Grundlage Handlungsfelder und Aufgaben für deren Entwicklung und Stärkung erarbeitet. Erfolgsfaktoren für die Zentrenentwicklung werden in einer integrierten Vorgehensweise identifiziert. Ansatzpunkte für die Umsetzung einer sachlich und räumlich integrierten Zentrenentwicklung und für die Überwindung möglicher Beschränkungen des Zentrenprogramms bieten Mehrfachförderkulissen. Sie entstehen in Folge des in einigen Bundesländern üblichen gebündelten Einsatzes von Fördermitteln in Gebieten mit komplexen städtebaulichen und sozialen Problemen. Sie bieten Potenziale zur Verstärkung und Ergänzung von Handlungsmöglichkeiten im Programm Aktive Stadt- und Ortsteilzentren durch die Nutzung aller vorhandenen Förderkulissen. Anhand einer Fallstudie zu einem Berliner Stadtteilzentrum und Fördergebiet im Programm Aktive Stadt- und Ortsteilzentren werden Vorgehensweisen zur Ermittlung dieser Potenziale sowie Handlungsansätze zu deren Nutzung erarbeitet. In einer analytischen Gegenüberstellung von relevanten Handlungserfordernissen im Zentrum und Interventionsmöglichkeiten und Maßnahmenplanungen der bestehenden Förderkulissen werden Synergie- und Ergänzungspotenziale für die Zentrenentwicklung ermittelt. In der Fallstudie zeigt sich allerdings, dass diese Potenziale kaum ausgeschöpft werden. Daher werden in der Arbeit Handlungsansätze für eine Optimierung des Zusammenwirkens der Programme in der Mehrfachförderkulisse entwickelt. Online-Version im Universitätsverlag der TU Berlin (www.univerlag.tu-berlin.de) erschienen

Silver nanoparticle-doped zirconia capillaries for enhanced bacterial filtration

Membrane clogging and biofilm formation are the most serious problems during water filtration. Silver nanoparticle (Agnano) coatings on filtration membranes can prevent bacterial adhesion and the initiation of biofilm formation. In this study, Agnano are immobilized via direct reduction on porous zirconia capillary membranes to generate a nanocomposite material combining the advantages of ceramics being chemically, thermally and mechanically stable with nanosilver, an efficient broadband bactericide for water decontamination. The filtration of bacterial suspensions of the fecal contaminant Escherichia coli reveals highly efficient bacterial retention capacities of the capillaries of 8 log reduction values, fulfilling the requirements on safe drinking water according to the U.S. Environmental Protection Agency. Maximum bacterial loading capacities of the capillary membranes are determined to be 3 × 109 bacterial cells/750 mm2 capillary surface until back flushing is recommendable. The immobilized Agnano remain accessible and exhibit strong bactericidal properties by killing retained bacteria up to maximum bacterial loads of 6 × 108 bacterial cells/750 mm2 capillary surface and the regenerated membranes regain filtration efficiencies of 95–100%. Silver release is moderate as only 0.8% of the initial silver loading is leached during a three-day filtration experiment leading to average silver contaminant levels of 100 μg/L

Microbiota independent effects of oligosaccharides on Caco-2 cells -A semi-targeted metabolomics approach using DI-FT-ICR-MS coupled with pathway enrichment analysis

Milk oligosaccharides (MOS) and galactooligosaccharides (GOS) are associated with many benefits, including anti-microbial effects and immune-modulating properties. However, the cellular mechanisms of these are largely unknown. In this study, the effects of enriched GOS and MOS mixtures from caprine and bovine milk consisting mainly 6'-galactosyllactose, 3'-sialyllactose, and 6'-sialyllactose on Caco-2 cells were investigated, and the treatment-specific metabolomes were described. In the control, the cells were treated with a sugar mix consisting of one-third each of glucose, galactose and lactose. A local metabolomics workflow with pathway enrichment was established, which specifically addresses DI-FT-ICR-MS analyses and includes adaptations in terms of measurement technology and sample matrices. By including quality parameters, especially the isotope pattern, we increased the precision of annotation. The independence from online tools, the fast adaptability to changes in databases, and the specific adjustment to the measurement technology and biomaterial used, proved to be a great advantage. For the first time it was possible to find 71 active pathways in a Caco-2 cell experiment. These pathways were assigned to 12 main categories, with amino acid metabolism and carbohydrate metabolism being the most dominant categories in terms of the number of metabolites and metabolic pathways. Treatment of Caco-2 cells with high GOS and glucose contents resulted in significant effects on several metabolic pathways, whereas the MOS containing treatments resulted only for individual metabolites in significant changes. An effect based on bovine or caprine origin alone could not be observed. Thus, it was shown that MOS and GOS containing treatments can exert microbiome-independent effects on the metabolome of Caco-2 cells

Methotrexate-associated toxicity in children with Down syndrome and acute lymphoblastic leukemia during consolidation therapy with high dose methotrexate according to ALL-BFM treatment regimen

Children with Down syndrome (DS) and acute lymphoblastic leukemia (ALL) often suffer from severe toxicities during treatment, especially with high-dose methotrexate (HD-MTX). Systematic data on methotrexate (MTX) toxicity in these patients are rare. We analyzed seven MTX-associated toxicities during consolidation therapy in 103 DS- and 1,109 non-DS-patients (NDS) with ALL (NDS-ALL) enrolled in ALL-Berlin-Frankfurt-Münster (ALL-BFM) trials between 1995-2016 and 1995-2007, respectively. Patients received four courses MTX (5 g/m2 each) plus intrathecal MTX and 6-mercaptopurine (6-MP). From 2004 onwards, a dose of 0.5 g/m2 in the first MTX course has been recommended for DS-patients. DS-patients showed higher rates of grade 3/4 toxicities after the first course with 5 g/m2 MTX compared to NDS-patients (grade 3/4 toxicities 62 in 45 DS-patients vs 516 in 1,089 NDS-patients, P<0.001). The dose reduction (0.5 g/m2) in DS-patients has reduced toxicity (39 in 51 patients, P<0.001) without increasing the relapse risk (reduced dose, 5-year cumulative relapse incidence = 0.09±0.04 vs high dose, 0.10±0.05, P=0.51). MTX dose escalation to 1.0 g/m2 for DS-patients who tolerated 0.5 g/m2 (n= 28 of 51 patients) did not result in an increased rate of grade 3/4 toxicities after the second course (P=0.285). Differences in MTX plasma levels at 42 and 48 hours after the start of the first methotrexate infusion did not explain higher toxicity rates in DS-patients treated with 0.5 g/m2 compared to NDS-patients treated with 5 g/m2 Within the DS cohort a higher MTX plasma level was associated with increased toxicity. In conclusion, dose reduction in the first MTX course reduced severe toxicities without increasing the risk of relapse. (ClinicalTrials.gov identifier: NTC00430118, NCT01117441)

Precision Nutrition in Chronic Inflammation

The molecular foundation of chronic in fl ammatory diseases (CIDs) can differ markedly between individuals. As our understanding of the biochemical mechanisms underlying individual disease manifestations and progressions expands, new strategies to adjust treatments to the patient ’ s characteristics will continue to profoundly transform clinical practice. Nutrition has long been recognized as an important determinant of in fl ammatory disease phenotypes and treatment response. Yet empirical work demonstrating the therapeutic effectiveness of patient-tailored nutrition remains scarce. This is mainly due to the challenges presented by long-term effects of nutrition, variations in inter-individual gastrointestinal microbiota, the multiplicity of human metabolic pathways potentially affected by food ingredients, nutrition behavior, and the complexity of food composition. Historically, these challenges have been addressed in both human studies and experimental model laboratory studies primarily by using individual nutrition data collection in tandem with large- scale biomolecular data acquisition (e.g. genomics, metabolomics, etc.). This review highlights recent fi ndings in the fi eld of precision nutrition and their potential implications for the development of personalized treatment strategies for CIDs. It emphasizes the importance of computational approaches to integrate nutritional information into multi- omics data analysis and to predict which molecular mechanisms may explain how nutrients intersect with disease pathways. We conclude that recent fi ndings point towards the unexhausted potential of nutrition as part of personalized medicine in chronic in fl ammation

To what extent does a regional dialect and accent impact on the development of reading and writing skills?

The issue of whether a regional accent and/or dialect impact(s) on the development of literacy skills remains current in the UK. For decades the issue has dogged debate about education outcomes, portable skills and employability. The article summarizes research on the topic using systematic review methodology. A scoping review was undertaken with the research question ‘To what extent does a regional dialect and accent impact on the development of reading and writing skills?’. The review covers research relevant to the teaching of 5-16 year olds in England, but also draws on research within Europe, the USA, Australia and the Caribbean. The results suggest that curricula have marginalized language variation; that the impact of regional accent and dialect on writing is relatively minor; that young people are adept at style-shifting between standard and non-standard forms; and that inappropriate pedagogical responses to regional variation can have detrimental effects on children’s educational achievement