Excitation Waves on a Minimal Small-World Model

We examine traveling-wave solutions on a regular ring network with one additional long-range link that spans a distance d. The nodes obey the FitzHugh-Nagumo kinetics in the excitable regime. The additional shortcut induces a plethora of spatio-temporal behavior that is not present without it. We describe the underlying mechanisms for different types of patterns: propagation failure, period decreasing, bistability, shortcut blocking and period multiplication. For this purpose, we investigate the dependence on d, the network size, the coupling range in the original ring and the global coupling strength and present a phase diagram summarizing the different scenarios. Furthermore, we discuss the scaling behavior of the critical distance by analytical means and address the connection to spatially continuous excitable media.Comment: 14 pages, 11 figure

Alternative Approaches for Medical Countermeasures to Biological and Chemical Terrorism and Warfare

The desire to develop and evaluate drugs as potential countermeasures for biological and chemical threats requires test systems that can also substitute for the clinical trials normally crucial for drug development. Animal models have limited predictivity for drug efficacy, as is well known from many disappointments in clinical trials. Traditional in vitro and in silico approaches are not really game changers here, but the substantial investment into novel tools now underway might bring about a second generation of alternative approaches. The avenue pursued focuses primarily on the development of a Human on a Chip, i.e., the combination of different three-dimensional (stem) cell-based organ equivalents combined with microfluidics. The prospects of such approaches, their impact on the field of alternative approaches, and necessary complementary activities are discussed. The need to adapt quality assurance measures and experiences from validation is stressed

Weighted Gene Correlation Network Analysis (WGCNA) Reveals Novel Transcription Factors Associated With Bisphenol A Dose-Response

Despite Bisphenol-A (BPA) being subject to extensive study, a thorough understanding of molecular mechanism remains elusive. Here we show that using weighted gene correlation network analysis (WGCNA), which takes advantage of a graph theoretical approach to understanding correlations amongst genes and grouping genes into modules that typically have co-ordinated biological functions and regulatory mechanisms, that despite some commonality in altered genes, there is minimal overlap between BPA and estrogen in terms of network topology. We confirmed previous findings that ZNF217 and TFAP2C are involved in the estrogen pathway, and are implicated in BPA as well, although for BPA they appear to be active in the absence of canonical estrogen-receptor driven gene expression. Furthermore, our study suggested that PADI4 and RACK7/ZMYNDB8 may be involved in the overlap in gene expression between estradiol and BPA. Lastly, we demonstrated that even at low doses there are unique transcription factors that appear to be driving the biology of BPA, such as SREBF1. Overall, our data is consistent with other reports that BPA leads to subtle gene changes rather than profound aberrations of a conserved estrogen signaling (or other) pathways

Zur Entwicklung der Pockenschutzimpfung unter besonderer Berücksichtigung Thüringens im 18. und 19. Jahrhundert

1980 erklärte die WHO die Pocken als erste Krankheit der Menschheitsgeschichte für ausgerottet. Die Entwicklung dahin begann in Europa 1721 mit der Einführung der Pockeninokulation in England. Die Staaten Europas schufen sich in den folgenden Jahren eigene Impfwesen. Ziel der vorliegenden Arbeit war, diese Entwicklung in den Thüringer Kleinstaaten zu untersuchen. Darüber hinaus wird die Rolle der Thüringer Ärzte im Rahmen dieser Entwicklung dargestellt. Es wird ein Einblick in die technischen und organisatorischen Abläufe gegeben. Anhand der gesetzlichen Regelungen läßt sich die Entschlossenheit der einzelnen Regierungen erkennen, die Pocken zu bekämpfen

Die Paronomasie als werbestilistisches Element – Zur gefühlten Inflation einer rhetorischen Figur

Paronomasias are as rhetorical figures of repetition intentional combinations of at least similar, at best, equal, semantically and/or etymology but different words, the similarity in sound and/or writing is justified. Given the inflation of "Wau, ist das günstig", "MyTaxi holt dich app", "Hörvorragende Angebote"… questioned the contribution the spoken power of this particular figure of advertisement speech. Basis is the theory that advertising language is as comprehensive "semiosis of linguistic, paralinguistic and extra-linguistic" (Fix 1996) interpreted. Differentiated by primary (homonymous, homophonic, homographic) and secondary (paronymous) Paronomasias, he then examines the primary as a semiotic unintended inventory based on a reductionist body, which leads to the extraction of structural usage patterns and checks the validity of two general schemes

Highly purified lipoteichoic acid from Staphylococcus aureus induces procoagulant activity and tissue factor expression in human monocytes but is a weak inducer in whole blood: Comparison with peptidoglycan

Lipoteichoic acid from Staphylococcus aureus was a potent inducer of procoagulant activity in isolated mononuclear cells but not in whole blood. In contrast, staphylococcal peptidoglycan showed equal levels of potency in isolated mononuclear cells and whole blood, suggesting that peptidoglycan is an important inducer of procoagulant activity in severe sepsis involving gram-positive bacteria

A Toxicology for the 21st Century—Mapping the Road Ahead

The landmark publication by the National Research Council putting forward a vision of a toxicology for the 21st century in 2007 has created an atmosphere of departure in our field. The alliances formed, symposia and meetings held and the articles following are remarkable, indicating that this is an idea whose time has come. Most of the discussion centers on the technical opportunities to map pathways of toxicity and the financing of the program. Here, the other part of the work ahead shall be discussed, that is, the focus is on regulatory implementation once the technological challenges are managed, but we are well aware that the technical aspects of what the National Academy of Science report suggests still need to be addressed: A series of challenges are put forward which we will face in addition to finding a technical solution (and its funding) to set this vision into practice. This includes the standardization and quality assurance of novel methodologies, their formal validation, their integration into test strategies including threshold setting and finally a global acceptance and implementation. This will require intense conceptual steering to have all pieces of the puzzle come together

Sub-systems in nearby solar-type wide binaries

We conducted a deep survey of resolved sub-systems among wide binaries with solar-type components within 67 pc from the Sun. Images of 61 stars in the K and H bands were obtained with the NICI adaptive-optics instrument on the 8-m Gemini-South telescope. Our maximum detectable magnitude difference is about 5mag and 7.8mag at 0.15" and 0.9" separations, respectively. This enables a complete census of sub-systems with stellar companions in the projected separation range from 5 to 100 AU. Out of 7 such companions found in our sample, only one was known previously. We determine that the fraction of sub-systems with projected separations above 5 AU is 0.12 +- 0.04 and that the distribution of their mass ratio is flat, with a power-law index 0.2 +- 0.5. Comparing this with the properties of closer spectroscopic sub-systems (separations below 1 AU), it appears that the mass-ratio distribution does not depend on the separation. The frequency of sub-systems in the separation ranges below 1 AU and between 5 and 100 AU is similar, about 0.15. Unbiased statistics of multiplicity higher than two, advanced by this work, provide constraints on star-formation theory.Comment: Accepted by Astronomical Journal. 13 pages, 5 figure

Coherent backscattering of Bose-Einstein condensates in two-dimensional disorder potentials

We study quantum transport of an interacting Bose-Einstein condensate in a two-dimensional disorder potential. In the limit of vanishing atom-atom interaction, a sharp cone in the angle-resolved density of the scattered matter wave is observed, arising from constructive interference between amplitudes propagating along reversed scattering paths. Weak interaction transforms this coherent backscattering peak into a pronounced dip, indicating destructive instead of constructive interference. We reproduce this result, obtained from the numerical integration of the Gross-Pitaevskii equation, by a diagrammatic theory of weak localization in presence of a nonlinearity.Comment: 4 pages, 4 figure