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- ItemDifferentialgeometrie im Grossen (hybrid meeting)(Zürich : EMS Publ. House, 2021) Hamenstädt, Ursula; Lang, Urs; Weinkove, BenThe field of classical differential geometry has expanded enormously over the last several decades, helped by the development of tools from neighboring fields such as partial differential equations, complex analysis and geometric topology. In the spirit of the previous meetings in the series, this meeting will bring together researchers from apparently separate subfields of differential geometry, but whose work is linked by common themes. In particular, this meeting will emphasize intrinsic geometric questions motivated by the classification and rigidity of global geometric structures and the interaction of curvature with the underlying geometry and topology.
- ItemPath integral solutions for n-dimensional stochastic differential equations under α-stable Lévy excitation(College Park, Md : [Verlag nicht ermittelbar], 2023) Zan, Wanrong; Xu, Yong; Kurths, JürgenIn this paper, the path integral solutions for a general n-dimensional stochastic differential equations (SDEs) with α-stable Lévy noise are derived and verified. Firstly, the governing equations for the solutions of n-dimensional SDEs under the excitation of α-stable Lévy noise are obtained through the characteristic function of stochastic processes. Then, the short-time transition probability density function of the path integral solution is derived based on the Chapman-Kolmogorov-Smoluchowski (CKS) equation and the characteristic function, and its correctness is demonstrated by proving that it satisfies the governing equation of the solution of the SDE, which is also called the Fokker-Planck-Kolmogorov equation. Besides, illustrative examples are numerically considered for highlighting the feasibility of the proposed path integral method, and the pertinent Monte Carlo solution is also calculated to show its correctness and effectiveness.
- ItemAuthor Correction: A combination of electrochemistry and mass spectrometry to monitor the interaction of reactive species with supported lipid bilayers (Scientific Reports, (2020), 10, 1, (18683), 10.1038/s41598-020-75514-7)(London : Nature Publishing Group, 2021) Ravandeh, M.; Kahlert, H.; Jablonowski, H.; Lackmann, J.-W.; Striesow, J.; Agmo Hernández, V.; Wende, K.Correction to: Scientific Reports https://doi.org/10.1038/s41598-020-75514-7, published online 29 October 2020
- ItemUnderstanding Business Environments and Success Factors for Emerging Bioeconomy Enterprises through a Comprehensive Analytical Framework(Basel : MDPI, 2020) Adamseged, Muluken Elias; Grundmann, PhilippThe development toward the bioeconomy requires, among others, generating and institutionalizing knowledge that contributes to technical and nontechnical inventions and innovations. Efforts to support innovation are often linked with the development of business models that facilitate the development in bioeconomy. However, the interdependences between the business models and their business environments are not sufficiently well understood in a way where misalignments that can obstruct the development can be dealt with adequately. Given this lacuna, this research aims to contribute to the development of a comprehensive analytical framework for better understanding the conditions of business environment as well as empirically apply the framework in an empirical study on cases of bioeconomy enterprises in Europe. In this paper, a comprehensive business environment framework is developed and applied for analyzing over 80 cases, thereby allowing for critical action arenas and crucial success factors to be identified. The findings are derived from a systematic application of the framework to relevant action arenas for business development: institutional development, technology and knowledge, consumers’ agency, market structure, funding, resource and infrastructure, and training and education. The results show that businesses in the bioeconomy, unlike other businesses, have to deal with more and very specific constraining legislative issues, infant and non-adapted technology and knowledge, as well as unclear values and perceptions of consumers. Due to this, businesses have to develop new forms of cooperation with different stakeholders. Successful businesses are characterized by the fact that they develop specific strategies, steering structures, and processes with a particular focus on learning and innovation to overcome misalignments between the business environment and their business models. Focusing efforts on learning and innovation in institutional development, technology and knowledge, consumers’ agency, and funding are especially promising as these turned out to be particularly critical and in particular need of institutional alignment for reducing different kinds of transaction costs in the development of bioeconomy.
- ItemMicromotor-mediated sperm constrictions for improved swimming performance(Berlin ; Heidelberg : Springer, 2021) Striggow, Friedrich; Nadporozhskaia, Lidiia; Friedrich, Benjamin M.; Schmidt, Oliver G.; Medina-Sánchez, MarianaSperm-driven micromotors, consisting of a single sperm cell captured in a microcap, utilize the strong propulsion generated by the flagellar beat of motile spermatozoa for locomotion. It enables the movement of such micromotors in biological media, while being steered remotely by means of an external magnetic field. The substantial decrease in swimming speed, caused by the additional hydrodynamic load of the microcap, limits the applicability of sperm-based micromotors. Therefore, to improve the performance of such micromotors, we first investigate the effects of additional cargo on the flagellar beat of spermatozoa. We designed two different kinds of microcaps, which each result in different load responses of the flagellar beat. As an additional design feature, we constrain rotational degrees of freedom of the cell’s motion by modifying the inner cavity of the cap. Particularly, cell rolling is substantially reduced by tightly locking the sperm head inside the microcap. Likewise, cell yawing is decreased by aligning the micromotors under an external static magnetic field. The observed differences in swimming speed of different micromotors are not so much a direct consequence of hydrodynamic effects, but rather stem from changes in flagellar bending waves, hence are an indirect effect. Our work serves as proof-of-principle that the optimal design of microcaps is key for the development of efficient sperm-driven micromotors.
- ItemGenotyping of methicillin resistant Staphylococcus aureus from the United Arab Emirates([London] : Macmillan Publishers Limited, part of Springer Nature, 2020) Senok, Abiola; Nassar, Rania; Celiloglu, Handan; Nabi, Anju; Alfaresi, Mubarak; Weber, Stefan; Rizvi, Irfan; Müller, Elke; Reissig, Annett; Gawlik, Darius; Monecke, Stefan; Ehricht, RalfReports from Arabian Gulf countries have demonstrated emergence of novel methicillin resistant Staphylococcus aureus (MRSA) strains. To address the lack of data from the United Arab Emirates (UAE), genetic characterisation of MRSA identified between December 2017 and August 2019 was conducted using DNA microarray-based assays. The 625 MRSA isolates studied were grouped into 23 clonal complexes (CCs) and assigned to 103 strains. CC5, CC6, CC22 and CC30 represented 54.2% (n/N = 339/625) of isolates with other common CCs being CC1, CC8, CC772, CC361, CC80, CC88. Emergence of CC398 MRSA, CC5-MRSA-IV Sri Lanka Clone and ST5/ST225-MRSA-II, Rhine-Hesse EMRSA/New York-Japan Clone in our setting was detected. Variants of pandemic CC8-MRSA-[IVa + ACME I] (PVL+) USA300 were detected and majority of CC772 strains were CC772-MRSA-V (PVL+), “Bengal- Bay Clone”. Novel MRSA strains identified include CC5-MRSA-V (edinA+), CC5-MRSA-[VT + fusC], CC5-MRSA-IVa (tst1+), CC5-MRSA-[V/VT + cas + fusC + ccrA/B-1], CC8-MRSA-V/VT, CC22-MRSA-[IV + fusC + ccrAA/(C)], CC45-MRSA-[IV + fusC + tir], CC80-MRSA-IVa, CC121-MRSA-V/VT, CC152-MRSA-[V + fusC] (PVL+). Although several strains harboured SCC-borne fusidic acid resistance (fusC) (n = 181), erythromycin/clindamycin resistance (ermC) (n = 132) and gentamicin resistance (aacA-aphD) (n = 179) genes, none harboured vancomycin resistance genes while mupirocin resistance gene mupR (n = 2) and cfr gene (n = 1) were rare. An extensive MRSA repertoire including CCs previously unreported in the region and novel strains which probably arose locally suggest an evolving MRSA landscape. © 2020, The Author(s).
- ItemModified wavelet analysis of ECoG-pattern as promising tool for detection of the blood–brain barrier leakage([London] : Macmillan Publishers Limited, part of Springer Nature, 2021) Runnova, Anastasiya; Zhuravlev, Maksim; Ukolov, Rodion; Blokhina, Inna; Dubrovski, Alexander; Lezhnev, Nikita; Sitnikova, Evgeniya; Saranceva, Elena; Kiselev, Anton; Karavaev, Anatoly; Selskii, Anton; Semyachkina-Glushkovskaya, Oxana; Penzel, Thomas; Kurths, JurgenA new approach for detection oscillatory patterns and estimation of their dynamics based by a modified CWT skeleton method is presented. The method opens up additional perspectives for the analysis of subtle changes in the oscillatory activity of complex nonstationary signals. The method was applied to analyze unique experimental signals obtained in usual conditions and after the non-invasive increase in the blood–brain barrier (BBB) permeability in 10 male Wistar rats. The results of the wavelet-analysis of electrocorticography (ECoG) recorded in a normal physiological state and after an increase in the BBB permeability of animals demonstrate significant changes between these states during wakefulness of animals and an essential smoothing of these differences during sleep. Sleep is closely related to the processes of observed changes in the BBB permeability.
- ItemConvex Geometry and its Applications (hybrid meeting)(Zürich : EMS Publ. House, 2021) Barthe, Franck; Ludwig, MonikaThe geometry of convex domains in Euclidean space plays a central role in several branches of mathematics: functional and harmonic analysis, the theory of PDE, linear programming and, increasingly, in the study of algorithms in computer science. The purpose of this meeting was to bring together researchers from the analytic, geometric and probabilistic groups who have contributed to these developments.
- ItemThe Active Galactic Nuclei in the Hobby-Eberly Telescope Dark Energy Experiment Survey (HETDEX). III. A Red Quasar with Extremely High Equivalent Widths Showing Powerful Outflows(London : Institute of Physics Publ., 2022) Liu, Chenxu; Gebhardt, Karl; Kollatschny, Wolfram; Ciardullo, Robin; Mentuch Cooper, Erin; Davis, Dustin; Farrow, Daniel J.; Finkelstein, Steven L.; Gawiser, Eric; Gronwall, Caryl; Hill, Gary J.; House, Lindsay; Schneider, Donald P.; Urrutia, Tanya; Zeimann, Gregory R.We report an active galactic nucleus (AGN) with an extremely high equivalent width (EW), EWLyα+N V,rest ≳921 Å, in the rest frame, at z ∼ 2.24 in the Hobby-Eberly Telescope Dark Energy Experiment Survey (HETDEX), as a representative case of the high-EW AGN population. The continuum level is a nondetection in the HETDEX spectrum; thus the measured EW is a lower limit. The source is detected with significant emission lines (>7σ) at Lyα + N v λ1241, C iv λ1549, and a moderate emission line (∼4σ) at He ii λ1640 within the wavelength coverage of HETDEX (3500-5500 Å). The r-band magnitude is 24.57 from the Hyper Suprime-Cam-HETDEX joint survey with a detection limit of r = 25.12 at 5σ. The Lyα emission line spans a clearly resolved region of ∼10″ (85 kpc) in diameter. The Lyα line profile is strongly double peaked. The spectral decomposed blue gas and red gas Lyα emission are separated by ∼1.″2 (10.1 kpc) with a line-of-sight velocity offset of ∼1100 km s−1. This source is probably an obscured AGN with powerful winds.
- ItemMode competition in broad-ridge-waveguide lasers(Bristol : IOP Publ., 2020) Koester, J.-P.; Putz, A.; Wenzel, H.; Wünsche, H.-J.; Radziunas, M.; Stephan, H.; Wilkens, M.; Zeghuzi, A.; Knigge, A.The lateral brightness achievable with high-power GaAs-based laser diodes having long and broad waveguides is commonly regarded to be limited by the onset of higher-order lateral modes. For the study of the lateral-mode competition two complementary simulation tools are applied, representing different classes of approximations. The first tool bases on a completely incoherent superposition of mode intensities and disregards longitudinal effects like spatial hole burning, whereas the second tool relies on a simplified carrier transport and current flow. Both tools yield agreeing power-current characteristics that fit the data measured for 5-23 µm wide ridges. Also, a similarly good qualitative conformance of the near and far fields is found. However, the threshold of individual modes, the partition of power between them at a given current, and details of the near and far fields show differences. These differences are the consequence of a high sensitivity of the mode competition to details of the models and of the device structure. Nevertheless, it can be concluded concordantly that the brightness rises with increasing ridge width irrespective of the onset of more and more lateral modes. The lateral brightness W mm-1at 10 MW cm-2 power density on the front facet of the investigated laser with widest ridge (23 µm) is comparable with best values known from much wider broad-area lasers. In addition, we show that one of the simulation tools is able to predict beam steering and coherent beam coupling without introducing any phenomenological coupling coefficient or asymmetries. © 2020 The Author(s). Published by IOP Publishing Ltd.