Osteochondral lesion of the talus: still a problem?

Osteochondral lesion of the talus (OLT) often occurs after ankle trauma or repetitive micro-traumata, whereas the actual etiology remains unclear. The most common symptoms are local pain deep in the medial or lateral ankle that increases with weight-bearing and activity, accompanied by tenderness and swelling. Eventually, most patients with symptomatic or unstable OLT require surgery. Many reasonable operative techniques have been described, whereas most lead to similar and satisfactory results. They can be divided into cartilage repair, cartilage regeneration and cartilage replacement techniques. The OLT size and morphology in the first place but also surgeon and individual patient aspects are considered when it comes to surgery. For high postoperative success and low recurrence rates, underlying causes, for example, ligamentous instability and hindfoot malalignment should also be addressed during surgery

Visually Explaining Publication Ranks in Citation-based Literature Search with PURE Suggest

Tracing citation links helps retrieve related publications. While most tools only allow the user to follow the citations of a single publication, some approaches support jointly analyzing the citations of a set of publications. Along similar lines, PURE suggest provides a detailed visual explanation of the ranking of suggested publications. The ranking is based on a score that combines citation numbers with keyword matching and is shown as a glyph for each publication. A citation network component references this glyph and visually embeds it into a timeline and cluster visualization

Accurate cosmic shear errors: do we need ensembles of simulations?

Accurate inference of cosmology from weak lensing shear requires an accurate shear power spectrum covariance matrix. Here, we investigate this accuracy requirement and quantify the relative importance of the Gaussian (G), super-sample covariance (SSC) and connected non-Gaussian (cNG) contributions to the covariance. Specifically, we forecast cosmological parameter constraints for future wide-field surveys and study how different covariance matrix components affect parameter bounds. Our main result is that the cNG term represents only a small and potentially negligible contribution to statistical parameter errors: the errors obtained using the G+SSC subset are within lesssim 5% of those obtained with the full G+SSC+cNG matrix for a Euclid-like survey. This result also holds for the shear two-point correlation function, variations in survey specifications and for different analytical prescriptions of the cNG term. The cNG term is that which is often tackled using numerically expensive ensembles of survey realizations. Our results suggest however that the accuracy of analytical or approximate numerical methods to compute the cNG term is likely to be sufficient for cosmic shear inference from the next generation of surveys

Jellyfish: A modular code for wave function-based electron dynamics simulations and visualizations on traditional and quantum compute architectures

Ultrafast electron dynamics have made rapid progress in the last few years. With Jellyfish, we now introduce a program suite that enables to perform the entire workflow of an electron-dynamics simulation. The modular program architecture offers a flexible combination of different propagators, Hamiltonians, basis sets, and more. Jellyfish can be operated by a graphical user interface, which makes it easy to get started for nonspecialist users and gives experienced users a clear overview of the entire functionality. The temporal evolution of a wave function can currently be executed in the time-dependent configuration interaction method (TDCI) formalism, however, a plugin system facilitates the expansion to other methods and tools without requiring in-depth knowledge of the program. Currently developed plugins allow to include results from conventional electronic structure calculations as well as the usage and extension of quantum-compute algorithms for electron dynamics. We present the capabilities of Jellyfish on three examples to showcase the simulation and analysis of light-driven correlated electron dynamics. The implemented visualization of various densities enables an efficient and detailed analysis for the long-standing quest of the electron–hole pair formation

A note on quadratic forms

Open Access via the Wiley Agreement AK and FH were supported by the Ger-manResearchFoundation(DFG)via thecollaborative researchcentres“Geometry:Deformationsand Rigidity” (grant no. SFB 1442–427320536) at the University of Münster and “Integral struc-tures in Geometry and Representation theory” (grant no. TRR 358–491392403) at the Universityof Bielefeld, respectively. AK was furthermore supported by the cluster “Mathematics Münster:Dynamics–Geometry–Structure” under grant no. EXC 2044–390685587. MR was supported by theDanish National Research Foundation (DNRF) through the “Copenhagen Center for Geometryand Topology” under grant no. DNRF151Peer reviewe

A note on quadratic forms

For a field extension $L/K$ we consider maps that are quadratic over $L$ but whose polarisation is only bilinear over $K$. Our main result is that all such are automatically quadratic forms over $L$ in the usual sense if and only if $L/K$ is formally unramified. In particular, this shows that over finite and number fields, one of the axioms in the standard definition of quadratic forms is superfluous.Comment: 12 pages, comments very welcome (in particular regarding previously known results!

Discovery of an X-ray cavity near the radio lobes of Cygnus A indicating previous AGN activity

Cygnus A harbours the nearest powerful radio jet of an Fanaroff-Riley (FR) class II radio galaxy in a galaxy cluster where the interaction of the jet with the intracluster medium (ICM) can be studied in detail. We use a large set of Chandra archival data, VLA and new LOFAR observations to shed new light on the interaction of the jets with the ICM. We identify an X-ray cavity in the distribution of the X-ray emitting plasma in the region south of the Cyg A nucleus which has lower pressure than the surrounding medium. The LOFAR and VLA radio observations show that the cavity is filled with synchrotron emitting plasma. The spectral age and the buoyancy time of the cavity indicates an age at least as large as the current Cyg A jets and not much larger than twice this time. We suggest that this cavity was created in a previous active phase of Cyg A when the energy output of the Active Galactic Nucleus (AGN) was about two orders of magnitude less than today.Comment: Letter submitted on 4 May 2012 to A&A, 4 pages, 4 figure

Einfluss der Mikrofluidik beim Membranemulgieren: Differentielle Betrachtung mittels numerischer Simulation und Experiment

The Influence of the local flow conditions on the membrane emulsification is examined by computational fluid dynamic. Pressure, flow velocity and pore diameter determine the droplet forming. Weber number We and Capillary number Ca found as dimensionless quantities to describe the membrane emulsification process. The mechanism of droplet breakup inside and outside the membrane is examined. Droplet breakup and coalescence processes result in topological change of the phase interface. A numerical model is developed, that allows describing droplet interactions including contact, coalescence and rebound, depending on the local flow conditions. The model is used for numerical simulation of multi disperse, multiphase fluid flow processes

The use of weightbearing radiographs to assess the stability of supination-external rotation fractures of the ankle

Background: Isolated lateral malleolar fractures usually result from a supination-external rotation (SER) injury and may include a deltoid ligament rupture. The necessity of operative treatment is based on the recognition of a relevant medial soft-tissue disruption. Currently used tests to assess ankle stability include manual stress radiographs and gravity stress radiographs, but seem to overestimate the need for fracture fixation. Methods: We investigated the use of weightbearing radiographs to distinguish stable and unstable isolated lateral malleolar fractures induced by the SER mechanism in 57 patients. Patients with stable fractures (SER type II according to the Lauge-Hansen classification) were treated non-operatively with varying external support. Forty-seven patients were evaluated by questionnaire and AOFAS ankle-hindfoot score. Follow-up was 18-120months (mean 62). Results: Fifty-one of fifty-seven (90%) patients were found to have stable fractures (SER type II) and were treated non-operatively. The AOFAS score was 96.1 points on average (range 85-100) at latest follow-up. Four patients reported minor complaints. A "moderate” correlation of risk factors (i.e. smoking) to delayed bone healing was found while the correlation of varying external support (i.e. bandage, cast) to the AOFAS score and delayed bone healing was "poor”. Conclusion: The use of weightbearing radiographs is an easy, pain-free, safe and reliable method to exclude the need for operative treatment, with excellent clinical outcome in the majority of the patients seen at latest follow-up. The delay of 3-10days until the decision about surgical treatment is well accepted by the patient

Visually Abstracting Event Sequences as Double Trees Enriched with Category‐Based Comparison

Event sequence visualization aids analysts in many domains to better understand and infer new insights from event data. Analysing behaviour before or after a certain event of interest is a common task in many scenarios. In this paper, we introduce, formally define, and position double trees as a domain-agnostic tree visualization approach for this task. The visualization shows the sequences that led to the event of interest as a tree on the left, and those that followed on the right. Moreover, our approach enables users to create selections based on event attributes to interactively compare the events and sequences along colour-coded categories. We integrate the double tree and category-based comparison into a user interface for event sequence analysis. In three application examples, we show a diverse set of scenarios, covering short and long time spans, non-spatial and spatial events, human and artificial actors, to demonstrate the general applicability of the approach