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The aim of this study was to analyze and compare the accuracy and quality of six 3D printing systems available on the market. Data acquisition was performed with 12 scans of human mandibles using an industrial 3D scanner and saved in STL format. These STL files were printed using six different printing systems. Previously defined distances were measured with a sliding caliper on the 72 printed mandibles. The printed models were then scanned once again. Measurements of volumes and surfaces for the STL files and the printed models were compared. Accuracy and quality were evaluated using industrial software. An analysis of the punctual aberration between the template and the printed model, based on a heat map, was also carried out. Secondary factors, such as costs, production times and expendable materials, were also examined. All printing systems performed well in terms of accuracy and quality for clinical usage. The Formiga P110 and the Form 2 showed the best results for volume, with average aberrations of 0.13 ± 0.23 cm3 and 0.12 ± 0.17 cm3, respectively. Similar results were achieved for the heat map aberration, with values of 0.008 ± 0.11 mm (Formiga P110) and 0.004 ± 0.16 mm (Form 2). Both printers showed no significant difference from the optimal neutral line (Formiga P110, p = 0.15; Form 2, p = 0.60). The cheapest models were produced by the Ultimaker 2+, with an average of 5€ per model, making such desktop printers affordable for rapid prototyping. Meanwhile, advanced printing systems with sterilizable and biocompatible printing materials, such as the Formiga P110 and the Form 2, fulfill the high expectations for maxillofacial surgery.

A 51-years-old male unilateral cochlear implant recipient underwent a magnet removal surgery 7 months after left ear MED-EL Mi1200 SYNCHRONY implantation, in order to reduce image artifact during magnet resonance imaging of neurofibromatosis 2 tumor progression. The implant magnet was removed under local anesthesia with the Magnet Removal Tool and the non-magnetic spacer was inserted with the Magnet Insertion Tool within 20 min. After the painless 1.5 hours MRI procedure the non-magnetic spacer was exchanged against the replacement implant magnet within 15 min. This is the first known published case of magnet removal from a MED-EL Mi1200 SYNCHRONY. Keywords: Cochlear implant, Implant, Radiology, Magnetic resonance imaging

We present a structured illumination microscopy based point localization estimator (SIMPLE) that achieves a 2-fold increase in single molecule localization precision compared to conventional centroid estimation methods. SIMPLE advances the recently introduced MINFLUX concept by using precisely phase-shifted sinusoidal wave patterns as nanometric rulers for simultaneous particle localization based on photon count variation over a 20 μm field of view. We validate SIMPLE in silico and experimentally on a TIRF-SIM setup using a digital micro-mirror device (DMD) as a spatial light modulator. Funding: “la Caixa” Foundation (ID 100010434, LCF/BQ/IN18/11660032); Marie Skłodowska-Curie Horizon 2020 (713673, 754558, 642157); Spanish Ministry Centro de Excelencia Severo Ochoa (SEV-2015-0522); MINECO’s Plan Nacional (BFU2017-86296-P); Generalitat de Catalunya (CERCA); Fundació Privada Cellex

Nonadherent polarized cells have been observed to have a pearlike, elongated shape. Using a minimal model that describes the cell cortex as a thin layer of contractile active gel, we show that the anisotropy of active stresses, controlled by cortical viscosity and filament ordering, can account for this morphology. The predicted shapes can be determined from the flow pattern only; they prove to be independent of the mechanism at the origin of the cortical flow, and are only weakly sensitive to the cytoplasmic rheology. In the case of actin flows resulting from a contractile instability, we propose a phase diagram of three-dimensional cell shapes that encompasses nonpolarized spherical, elongated, as well as oblate shapes, all of which have been observed in experiment.

This thesis investigates flexible self-organizing overlay networks for multimedia delivery - networks that are dynamically built on existing infrastructure to support the preferences of applications using them. These devices connect to each other to exchange videos. However, as the interests of their owners change, the overlay must adapt as well: existing connections must be replaced with connections to other relevant devices, such as devices of other visitors with similar interests. Deciding which devices should connect to each other, while also optimizing network performance is not trivial. This thesis attempts to solve that issue by using a flexible and scalable self-organizing overlay located between an application and its underlying network, which optimizes itself based the application's interest in content and network quality. A special focus is placed on including metrics relevant to multimedia delivery, such as jitter and bottleneck bandwidth, in the optimization. As these metrics cannot be predicted by a third node, established approaches such as matchmaking cannot be used. Therefore, a new approach based on a novel interest-property concept is introduced, which provides the flexibility of traditional matchmaking approaches, but also supports optimization based on parameters that can only be determined once two potential neighbours connect. In addition, a distributed way for nodes to estimate the level of service they are likely to receive to another node is introduced. A ``Flocks'' prototype overlay that implements the concepts and techniques described in this thesis is developed and evaluated. Results show that Flocks optimize even large overlays based on content and network metrics quickly and with modest overhead., Keine Zusammenfassung vorhanden, Stefan Wieser, Abweichender Titel laut Übersetzung der Verfasserin/des Verfassers, Klagenfurt, Alpen-Adria-Univ., Diss., 2012

Dynamic, large social events with concurrent activities, in which participants view, but also provide high-quality content to other visitors, pose one of many challenges to multimedia delivery. Distributing content in such a situation is difficult, and requires strong support from the underlying network, in order to quickly respond to changes in supply and demand. A Flock is a flexible overlay built in a self-organized, decentralized manner, relying on a simple interest-property concept. In this paper, we use Flocks to build large overlays that are both content- and Quality-of-Service (QoS) aware, and show how they adapt their structure dynamically, depending on interests in available QoS. We evaluate their performance under churn and large scale failures through extensive simulations, and practical experiments under Internet conditions on the Planet Lab, and present a selection of our results.

The Peer-to-Peer Epi-Transport Protocol (PPETP) [1] is a peer-to-peer protocol designed for multimedia data distribution between end users. While its robustness and flexibility are attractive properties for multimedia cloud services, its lack of routing poses an issue if distant or specific nodes must be reached to, for example, provide service, or cloud interoperability. This paper describes an extension to the PPETP that provides fast routing based on Dynamic Linked Data Structures (DLDS) and hierarchical topology aggregation. We provide a hierarchical routing algorithm with low runtime complexity that offers PPETP several suitable paths needed to draw full benefit from its ability to send multiple reduced streams. DLDS are used to speed-up the routing of packets belonging to long-lasting streams, in periods where their paths do not change. We describe the challenges encountered implementing this solution, and evaluate its performance through simulation.

When dealing with multimedia delivery, scalability, efficiency and Quality of Service (QoS) are challenging features for today's networks. Overlay networks can compensate for the lack of control over the network routers, but for real-world applications overlay network performance is an issue. This paper presents an efficient solution for software implementation of overlay network nodes. A new, advanced Distributed Linked Data Structures (DLDS) schema has been developed to provide scalable per-flow resource reservation and fast, searchless routing/forwarding table lookup. This schema has been integrated in a new overlay network framework that features hierarchical dynamic routing and QoS estimation based on performance measures of the underlying network. The proposed technique has been implemented and tested in a large, realistic network simulation environment, and experimental results are presented.

This paper introduces a scalable approach for efficient, low-cost multi-level Quality of Service (QoS) estimation in large overlay networks (ON). We modify an existing distributed partitioning algorithm, and use it to create "QoS maps". QoS maps empower applications to quickly predict several QoS metrics for any given route, and to obtain multiple alternative routes to any target node in the ON. We show that our modifications of the partitioning algorithm permit the aggregation of large hubs, but still preserve the sub-linear runtime of the original heuristic. Simulations with large ONs are performed to evaluate the proposed approach and demonstrate its scalability. Finally, we outline our estimation algorithm that we use to predict QoS and perform QoS aware routing in any given ON.

International audience; Resolving the dynamical interplay of proteins and lipids in the live-cell plasma membrane represents a central goal in current cell biology. Superresolution concepts have introduced a means of capturing spatial heterogeneity at a nanoscopic length scale. Similar concepts for detecting dynamical transitions (superresolution chronoscopy) are still lacking. Here, we show that recently introduced spot-variation fluorescence correlation spectroscopy allows for sensing transient confinement times of membrane constituents at dramatically improved resolution. Using standard diffraction-limited optics, spot-variation fluorescence correlation spectroscopy captures signatures of single retardation events far below the transit time of the tracer through the focal spot. We provide an analytical description of special cases of transient binding of a tracer to pointlike traps, or association of a tracer with nanodomains. The influence of trap mobility and the underlying binding kinetics are quantified. Experimental approaches are suggested that allow for gaining quantitative mechanistic insights into the interaction processes of membrane constituents.

Self-organizing overlay networks have received a lot of attention in the recent years. However, despite the popularity of content-aware and topology-aware overlay networks, surprisingly little research has been done to combine both approaches. In this paper, we create robust and flexible overlay networks that we call “Flocks”, which can be content-aware, topology-aware, or a combination of both. We model affinity with interests and properties and show the resulting overlay networks work in a decentralized, self-organizing way, and stabilize quickly.

Dual color single molecule tracking is a state-of-the-art fluorescence microscopy technique to study molecular associations. Featuring high spatial and temporal resolution, the method allows for catching associations with extremely high reliability. In this review, we describe robust data analysis approaches to identify and characterize molecular associations from dual color fluorescence images and show how colocalization can be statistically discriminated from accidental colocalizations. We discriminate the case of static analysis where colocalizations are revealed from individual dual color fluorescence images, and the case of dynamic analysis where colocalizations are tracked in time.

Objective: To compare costs of function- and pain-centred inpatient treatment in patients with chronic low back pain over 3 years of follow-up. Design: Cost analysis of a randomized controlled trial. Patients: A total of 174 patients with chronic low back pain were randomized to function- or pain-centred inpatient treatment. Methods: Data on direct and indirect costs were gathered by questionnaires sent to patients, health insurance providers, employers, and the Swiss Disability Insurance Company. Results: There was a non-significant difference in total medical costs after 3 years’ follow-up. Total costs were 77,305 Euros in the function-centred inpatient treatment group and 83,085 Euros in the pain-centred inpatient treatment group. Likewise, indirect costs after 3 years from lost work days were non-significantly lower in the function-centred in­patient treatment group (6354 Euros; 95% confidence interval -20,892, 8392) and direct medical costs were non-significantly higher in the function-centred inpatient treatment group (574 Euros; 95% confidence interval -862, 2011). Conclusion: The total costs of function-centred and pain-centred inpatient treatment were similar over the whole 3-year follow-up.