Analyse der Funktion des Zelloberflächen-Rezeptors Syndecan-4 bei der Wundheilung

Syndecan-4 ist ein transmembranes Heparansulfat-Proteoglykan, das eine wichtige Rolle bei der Wundheilung spielt. Im Rahmen der vorliegenden Arbeit wurden die zellulären Mechanismen untersucht, die den Verzögerungen der Wundheilung in Syndecan-4 Knockout Mäusen zu Grunde liegen. Dabei wurde in einem in vitro Wundkontraktionsmodell gezeigt, dass Syndecan-4 -/- Fibroblasten unter dem Einfluss des Wachstumsfaktors TGF-b1 deutlich reduzierte kontraktile Kräfte entwickeln. Zusätzlich wurde eine verminderte, TGF-b1 induzierte Differenzierung von Syndecan-4 -/- Fibroblasten in Myofibroblasten festgestellt. Bei der Untersuchung der TGF-b1 Signalübertragung stellte sich heraus, dass die Aktivierung der MAP Kinasen durch TGF-b1 in Syndecan-4 -/- Fibroblasten beeinträchtigt ist. Zudem wiesen Syndecan-4 defiziente Fibroblasten eine veminderte Migrationsfähigkeit auf, die auf Veränderungen in der Struktur und Signalweiterleitung der fokalen Kontakte dieser Zellen beruht

Untersuchungen zur Verminderung der mikrobiellen Besiedlung von wasserführenden Systemen dentaler Behandlungseinheiten durch Desinfektion mit Chlor

In dieser Arbeit wurden die wasserführenden Systeme von dentalen Behandlungseinheiten in 7 Zahnarztpraxen mittels 505 Wasserproben auf die Parameter Koloniezahlen, Legionellen, Pseudomonaden, ATP (Luminometrie), ausgewählte chemische Parameter und den Chlorgehalt untersucht. Vor Beginn der Desinfektionsphase wurde der Richtwert des RKI (100 KBE/ml) regelmäßig extrem überschritten (teilweise > 500.000 KBE/ml). In drei Proben wurde Legionella bozemanii und in einer Probe Pseudomonas aeruginosa nachgewiesen. Mehrfunktionsspritze und Turbine waren deutlich höher kontaminiert als der Mundglasfüller. Nach Etablierung einer Chlorung durch elektrochemische Aktivierung verminderten sich die Besiedlungen deutlich

A data-driven computational model for obesity-driven diabetes onset and remission through weight loss

Obesity is a major risk factor for the development of type 2 diabetes (T2D), where a sustained weight loss may result in T2D remission in individuals with obesity. To design effective and feasible intervention strategies to prevent or reverse T2D, it is imperative to study the progression of T2D and remission together. Unfortunately, this is not possible through experimental and observational studies. To address this issue, we introduce a data-driven computational model and use human data to investigate the progression of T2D with obesity and remission through weight loss on the same timeline. We identify thresholds for the emergence of T2D and necessary conditions for remission. We explain why remission is only possible within a window of opportunity and the way that window depends on the progression history of T2D, individual’s metabolic state, and calorie restrictions. These findings can help to optimize therapeutic intervention strategies for T2D prevention or treatment

Scaling laws and vortex profiles in 2D decaying turbulence

We use high resolution numerical simulations over several hundred of turnover times to study the influence of small scale dissipation onto vortex statistics in 2D decaying turbulence. A self-similar scaling regime is detected when the scaling laws are expressed in units of mean vorticity and integral scale, as predicted by Carnevale et al., and it is observed that viscous effects spoil this scaling regime. This scaling regime shows some trends toward that of the Kirchhoff model, for which a recent theory predicts a decay exponent $\xi=1$. In terms of scaled variables, the vortices have a similar profile close to a Fermi-Dirac distribution.Comment: 4 Latex pages and 4 figures. Submitted to Phys. Rev. Let

Quasi-stationary States of Two-Dimensional Electron Plasma Trapped in Magnetic Field

We have performed numerical simulations on a pure electron plasma system under a strong magnetic field, in order to examine quasi-stationary states that the system eventually evolves into. We use ring states as the initial states, changing the width, and find that the system evolves into a vortex crystal state from a thinner-ring state while a state with a single-peaked density distribution is obtained from a thicker-ring initial state. For those quasi-stationary states, density distribution and macroscopic observables are defined on the basis of a coarse-grained density field. We compare our results with experiments and some statistical theories, which include the Gibbs-Boltzmann statistics, Tsallis statistics, the fluid entropy theory, and the minimum enstrophy state. From some of those initial states, we obtain the quasi-stationary states which are close to the minimum enstrophy state, but we also find that the quasi-stationary states depend upon initial states, even if the initial states have the same energy and angular momentum, which means the ergodicity does not hold.Comment: 9 pages, 7 figure

Big Data and Performance: What Can Management Research Tell Us?

The special issue focuses on the theory and evidence linking the use of Big Data related technologies by businesses with their performance. Here we connect the papers accepted for the special issue to the overarching theme of Big Data as an emerging concept within the business management literature. We present two prominent case studies examining the use big data technologies on performance and strategy, followed by a discussion on how themes around Big Data may be examined from a theoretical perspective. Finally, based on a synthesis of papers in the current issue, we discuss the emerging issues and trends within the academic literature, relevant for future research

Slow relaxation in the two dimensional electron plasma under the strong magnetic field

We study slow relaxation processes in the point vortex model for the two-dimensional pure electron plasma under the strong magnetic field. By numerical simulations, it is shown that, from an initial state, the system undergoes the fast relaxation to a quasi-stationary state, and then goes through the slow relaxation to reach a final state. From analysis of simulation data, we find (i) the time scale of the slow relaxation increases linearly to the number of electrons if it is measured by the unit of the bulk rotation time, (ii) during the slow relaxation process, each electron undergoes an superdiffusive motion, and (iii) the superdiffusive motion can be regarded as the Levy flight, whose step size distribution is of the power law. The time scale that each electron diffuses over the system size turns out to be much shorter than that of the slow relaxation, which suggests that the correlation among the superdiffusive trajectories is important in the slow relaxation process.Comment: 11pages, 19 figures. Submitted to J. Phys. Soc. Jp

Eureka and beyond: mining's impact on African urbanisation

This collection brings separate literatures on mining and urbanisation together at a time when both artisanal and large-scale mining are expanding in many African economies. While much has been written about contestation over land and mineral rights, the impact of mining on settlement, notably its catalytic and fluctuating effects on migration and urban growth, has been largely ignored. African nation-states’ urbanisation trends have shown considerable variation over the past half century. The current surge in ‘new’ mining countries and the slow-down in ‘old’ mining countries are generating some remarkable settlement patterns and welfare outcomes. Presently, the African continent is a laboratory of national mining experiences. This special issue on African mining and urbanisation encompasses a wide cross-section of country case studies: beginning with the historical experiences of mining in Southern Africa (South Africa, Zambia, Zimbabwe), followed by more recent mineralizing trends in comparatively new mineral-producing countries (Tanzania) and an established West African gold producer (Ghana), before turning to the influence of conflict minerals (Angola, the Democratic Republic of Congo and Sierra Leone)