Hopf Bifurcations of Twisted States in Phase Oscillators Rings with Nonpairwise Higher-Order Interactions

Synchronization is an essential collective phenomenon in networks of interacting oscillators. Twisted states are rotating wave solutions in ring networks where the oscillator phases wrap around the circle in a linear fashion. Here, we analyze Hopf bifurcations of twisted states in ring networks of phase oscillators with nonpairwise higher-order interactions. Hopf bifurcations give rise to quasiperiodic solutions that move along the oscillator ring at nontrivial speed. Because of the higher-order interactions, these emerging solutions may be stable. Using the Ott--Antonsen approach, we continue the emergent solution branches which approach anti-phase type solutions (where oscillators form two clusters whose phase is $\pi$ apart) as well as twisted states with a different winding number.Comment: 24 pages, 8 figure

Production of Ultra-Cold-Neutrons in Solid \alpha-Oxygen

Our recent neutron scattering measurements of phonons and magnons in solid \alpha-oxygen have led us to a new understanding of the production mechanismen of ultra-cold-neutrons (UCN) in this super-thermal converter. The UCN production in solid \alpha-oxygen is dominated by the excitation of phonons. The contribution of magnons to UCN production becomes only slightly important above E >10 meV and at E >4 meV. Solid \alpha-oxygen is in comparison to solid deuterium less effcient in the down-scattering of thermal or cold neutrons into the UCN energy regime.Comment: 4 pages, 5 figuer

Dualities and dilemmas: contending with uncertainty in large-scale safety-critical projects

© 2016, Informa UK Limited, trading as Taylor & Francis Group. Uncertainty is a fact of project life. Most decisions that are made on a safety-critical project involve uncertainty, the consequences of which may be highly significant to the safe and timely delivery of the project. Based on interviews with project management practitioners on nine large-scale civil nuclear and aerospace projects, we explore how uncertainty emerges, and how project management practitioners identify, analyse and act on it. We make three important contributions. First, we present three approaches – structural, behavioural and relational – that individuals and organizations can adopt when contending with project uncertainty. Secondly, we characterize nine dualities at play in the management of project uncertainty and thirdly, we identify key differences between how civil nuclear and aerospace project managers confront project uncertainty, which have important implications for how projects might be organized in both these industry sectors. Drawing attention to the structural, behavioural and relational approaches to project uncertainty and the tensions that manifest themselves in each approach should enable the project management community to make progress in environments of high uncertainty where situations are often complex, rapidly changing and confusing, and yet where, for reasons of safety, failure is not an option

Timing and Tempo of Early and Successive Adaptive Radiations in Macaronesia

The flora of Macaronesia, which encompasses five Atlantic archipelagos (Azores, Canaries, Madeira, Cape Verde, and Salvage), is exceptionally rich and diverse

Intravesical Treatments of Bladder Cancer: Review

For bladder cancer, intravesical chemo/immunotherapy is widely used as adjuvant therapies after surgical transurethal resection, while systemic therapy is typically reserved for higher stage, muscle-invading, or metastatic diseases. The goal of intravesical therapy is to eradicate existing or residual tumors through direct cytoablation or immunostimulation. The unique properties of the urinary bladder render it a fertile ground for evaluating additional novel experimental approaches to regional therapy, including iontophoresis/electrophoresis, local hyperthermia, co-administration of permeation enhancers, bioadhesive carriers, magnetic-targeted particles and gene therapy. Furthermore, due to its unique anatomical properties, the drug concentration-time profiles in various layers of bladder tissues during and after intravesical therapy can be described by mathematical models comprised of drug disposition and transport kinetic parameters. The drug delivery data, in turn, can be combined with the effective drug exposure to infer treatment efficacy and thereby assists the selection of optimal regimens. To our knowledge, intravesical therapy of bladder cancer represents the first example where computational pharmacological approach was used to design, and successfully predicted the outcome of, a randomized phase III trial (using mitomycin C). This review summarizes the pharmacological principles and the current status of intravesical therapy, and the application of computation to optimize the drug delivery to target sites and the treatment efficacy

Organisationskultur. Eine Konkretisierung aus systemtheoretischer Perspektive

Kühl S. Organisationskultur. Eine Konkretisierung aus systemtheoretischer Perspektive. Managementforschung. 2018;28(1):7-35.Die Bestimmung des Verhältnisses von Informalität und Organisationskultur bereitet in der Organisationstheorie Schwierigkeiten. Das liegt daran, dass der Begriff Informalität häufig stillschweigend durch den Begriff der Organisationskultur ersetzt wurde, ohne dass dafür eine präzise, abgrenzungsscharfe Definition vorgenommen worden wäre. Unter Rückgriff auf Überlegungen von Dario Rodríguez argumentiert dieser Artikel, dass die beiden Begriffe Organisationskultur und Informalität das gleiche Phänomen bezeichnen: die nichtentschiedenen Entscheidungsprämissen einer Organisation. Dabei wird systematisch zwischen „unentscheidbaren Entscheidungsprämissen“ und „prinzipiell entscheidbaren, aber nicht entschiedenen Entscheidungsprämissen“ unterschieden. Es wird gezeigt, wie sich mit einer präzisen Bestimmung über das Konzept der Entscheidungsprämissen Ordnung in die „wilden Merkmallisten“ der Literatur sowohl über Informalität als auch Organisationskultur bringen lässt und empirische Phänomene genauer erfasst werden können