Baby Skyrmion chains

Previous results on multi-charged Baby Skyrmion solutions have pointed to a modular structure, comprised of charge two rings and single charge one Skyrmions, which combine to form higher charged structures. In this paper we present numerical evidence which shows an alternative finite chain, multi-charged global energy minimum Baby Skymion solution. We then proceed from the infinite plane, to Baby Skyrmions on a cylinder and then a torus, to obtain the solutions of periodic Baby Skyrmions, of which periodic segments will correspond to sections of large charge Baby Skyrmions in the plane

The Performance of Private Equity Funds: Does Diversification Matter?

This paper is the first systematic analysis of the impact of diversification on the performance of private equity funds. A unique data set allows the exact evaluation of diversification across the dimensions financing stages, industries, and countries. Very different levels of diversification can be observed across sample funds. While some funds are highly specialized others are highly diversified. The empirical results show that the rate of return of private equity funds declines with diversification across financing stages, but increases with diversification across industries. Accordingly, the fraction of portfolio companies which have a negative return or return nothing at all, increase with diversification across financing stages. Diversification across countries has no systematic effect on the performance of private equity funds

Molecular, genetic and epigenetic pathways of peroxynitrite-induced cellular toxicity

Oxidative stress plays a key role in the pathogenesis of cancer and many metabolic diseases; therefore, an effective antioxidant therapy would be of great importance in these circumstances. Nevertheless, convincing randomized clinical trials revealed that antioxidant supplementations were not associated with significant reduction in incidence of cancer, chronic diseases and all-cause mortality. As oxidation of essential molecules continues, it turns to nitro-oxidative stress because of the involvement of nitric oxide in pathogenesis processes. Peroxynitrite damages via several distinctive mechanisms; first, it has direct toxic effects on all biomolecules and causes lipid peroxidation, protein oxidation and DNA damage. The second mechanism involves the induction of several transcription factors leading to cytokine-induced chronic inflammation. Finally, it causes epigenetic perturbations that exaggerate nuclear factor kappa-B mediated inflammatory gene expression. Lessons-learned from the treatment of several chronic disorders including pulmonary diseases suggest that, chronic inflammation and glucocorticoid resistance are regulated by prolonged peroxynitrite production

The Early Eocene bird Gallinuloides wyomingensis - a stem group representative of Galliformes

We identified a second, perfectly preserved skeleton of the earliest known galliform bird, Gallinuloides wyomingensis Eastman. The new specimen clearly shows that G. wyomingensis does not belong to crown group Galliformes as assumed by earlier authors. In particular, the primitive presence of a deeply excavated, concave facies articularis scapularis at the coracoid precludes the inclusion of G. wyomingensis into crown group Galliformes. Gallinuloides wyomingensis is morphologically very similar to Paraortygoides messelensis Mayr, a nearly contemporaneous galliform from Messel, Germany. The exclusive presence of stem group galliform birds in pre−Oligocene deposits does not support the Gondwanan origin of Galliformes as evidenced by the Southern Hemisphere distribution of basal crown group members (Megapodiidae and Cracidae)

Können Stimmprothesen im MRT in situ verbleiben? Eine Untersuchung zur MRT-Sicherheit moderner Stimmprothesen

Einleitung: Stimmprothesen stellen heute den Goldstandard der stimmlichen Rehabilitation nach totaler Laryngektomie dar. Bei der technischen Weiterentwicklung der Prothesen kommen immer häufiger neue Werkstoffe (silberoxidhaltiges Silikon, Stahlröhrchen, Titanringe und auch Magnete) zum Einsatz. Insbesondere in der onkologischen Nachsorge kehlkopfloser Patienten mit Stimmprothese kommt deshalb immer wieder die Frage auf, ob eine bestimmte Stimmprothese MRT-sicher ist. Ziel der vorliegenden Arbeit war es daher, alle derzeit gängigen Stimmprothesenmodelle auf dem deutschen Markt auf ihre MRT-Sicherheit hin zu untersuchen.Material/Methode: Stimmprothesen des Typs: Provox 2, Provox Vega, Provox ActiValve (light, strong, extra strong), Blom Singer Classic 20fr, Blom-Singer Advantage (first generation, second generation) Blom-Singer Dual Valve, Tracoe Voicemaster, Eska Herrmann (flexion 60°, 75°, 90°), Adeva Highflow, Groningen 4 ULR und Heimomed Phonax wurden in einem Siemens Avanto MRT maximal 1,5 Tesla exponiert und die auftretenden Kräfte untersucht.Ergebnisse: Erwartungsgemäß zeigten die reinen Silikon- und Kunststoffprothesen keine Reaktion im MRT. Prothesen mit Titanbauteilen sind ebenfalls weitestgehend MRT-sicher. Stimmprothesen mit Metallteilen und Magneten verursachen im MRT Kräfte, die im Vortrag dargestellt werden.Schlussfolgerung: Kunststoff-Stimmprothesen sind MRT-sicher. Hersteller von Stimmprothesen mit Bauteilen aus Metall bzw. Magneten sollten Angaben zur MRT-Sicherheit ihrer Prothesen in die Produktinformation mit aufnehmen

Can voice prostheses remain in situ? An inquiry to ensure the safety of modern voice prostheses in MRI

We present a novel abstraction technique that exploits the compositionality of a concurrent system consisting of interacting components. It uses, given an invariant and a component of interest, bounded model checking (BMC) to quickly interpolate an abstraction of that component's environment. The abstraction may be refined by increasing the BMC bound. Furthermore, it is only defined over variables shared between the component and its environment, resulting in an aggressive abstraction with several applications. We demonstrate its use in a verification setting, as we report on our open source implementation in the NuSMV model checker which was used to perform a practical assessment with industrially-sized models from satellite case studies of ongoing missions. These models are expressed in a formalized dialect of the component-oriented and industrially standardized Architecture Analysis and Design Language (AADL)