[Virtual staff teamwork during the pandemic - development of digital training formats for community emergency response during the coronavirus pandemic]. / Virtuelle Stabsarbeit in Zeiten der Pandemie ­ Entwicklung digitaler Übungsformate in der zivilen Gefahrenabwehr während der Coronapandemie: Erfahrungen am Beispiel des Projekts ARMIHN.

Background: In the event of emergency response to large-scale incidents, such as a mass casualty incident (MCI) or a mass casualty incident-infectious disease (MCI-ID), regular training is essential in order to have experienced emergency personnel available in the event of an incident. Due to the pandemic drills often had to be cancelled or were only possible with small groups of people. It was often not possible to simulate a large-scale emergency with actors, so that the trainees could not be offered realistic scenarios of a mass casualty or disease incident. As part of two research projects, a digital platform for conducting training was used to avoid the risk of infection between participants during the exercises, so that on-site personnel deployment could be reduced to a minimum. The goal of this work was to evaluate end-user acceptance of the digital solution approaches. Methods: Within the framework of the project "Adaptive Resilience Management in Ports" (ARMIHN), a digital exercise platform was applied and evaluated with the help of participant surveys according to the focal points "implementation", "alternative possibilities", "learning effect" and "usability". The participants used the digital platform to exchange information and to communicate. For this purpose, various collaboration tools were embedded in the platform, which enabled simultaneous exchange of information in real time. Constant video communication with in-house and external authorities/teams was also established. Results: The potential of the digital platform as an alternative to on-site exercises was confirmed by the participating end users in the ARMIHN project with 90% agreement. The increase in subjective skills and knowledge gained during a MCI-ID was also predominantly rated approvingly (up to 70%). Participants who rated the implementation of the online format as well performed were significantly more likely to state that subjectively their ability to handle a MCI-ID had improved (p = 0.016). In contrast, virtual staff teamwork in real crisis situations was viewed critically by about half of respondents. Conclusion: Overall, the evaluation results point to the high end-user acceptance of the developed concept. Even though the aim is to evaluate the system over a longer period with a larger number of participants, the studies already conducted confirm the positive experiences in the respective projects.

Dispersible SnO2 :Sb and TiO2 Nanocrystals After Calcination at High Temperature.

High-temperature treatment of functional nanomaterials, through postsynthesis calcination, often represents an important step to unlock their full potential. However, such calcination steps usually severely limit the preparation of colloidal solutions of the nanoparticles due to the formation of sintered agglomerates. Herein, a simple route is reported to obtain colloidal solutions of calcined n-conductive antimony doped tin oxide (ATO) as well as titanium dioxide (TiO2 ) nanoparticles without the need for additional sacrificial materials. This is achieved by making use of the reduced contact between individual nanoparticles when they are assembled into aerogels. Following the calcination of the aerogels at 500 °C, redispersion of the nanoparticles into stable colloidal solutions with various solvents can be achieved. Although a slight degree of sintering is inevitable, the size of the resulting aggregates in solution is still remarkably small with values below 30 nm.

Intercalation-free, fast switching of mesoporous antimony doped tin oxide with cathodically coloring electrochromic dyes.

Mesoporous nanoparticle layers of transparent conductive oxides (TCOs) with anchored organic dyes are of great interest for electrochromic applications. Herein, we prepared mesoporous layers of antimony doped tin oxide (ATO) consisting of only 5 nm large particles with a low Sb concentration (2% antimony). The particles were prepared via a modified synthesis procedure based on hexahydroxostannate and pure Sb(v) hexahydroxoantimonate(v). We show that the ATO layers benefit from using a non-intercalating electrolyte such as tetrabutylammonium perchlorate (TBAP) compared to lithium perchlorate. Especially in the negative potential range, negative side effects, such as degradation due to lithium intercalation, are reduced. Furthermore, comparing the behavior of particles with varying antimony doping concentrations showed that the particles doped with 2% Sb are most suitable with respect to their conductivity and transparency. When modified with an electrochromic dye (viologen), the hybrid electrodes allow fully reversible (de)coloration with the non-intercalating electrolyte. Similar viologen/TiO2 electrodes on the other hand show severely restricted performance with the non-intercalating electrolyte as the oxidation of the dye is partially inhibited. Finally, we built a full electrochromic device composed of two ATO electrodes, each bearing a different electrochromic dye with TBAP as the electrolyte. Despite the dense morphology of the layers due to the small particle size as well as the large size of the electrolyte cation, the device displays remarkable switching times below 0.5 s.

Reactive Additive Capillary Stamping with Double Network Hydrogel-Derived Aerogel Stamps under Solvothermal Conditions.

Integration of solvothermal reaction products into complex thin-layer architectures is frequently achieved by combinations of layer transfer and subtractive lithography, whereas direct additive substrate patterning with solvothermal reaction products has remained challenging. We report reactive additive capillary stamping under solvothermal conditions as a parallel contact-lithographic access to patterns of solvothermal reaction products in thin-layer configurations. To this end, corresponding precursor inks are infiltrated into mechanically robust mesoporous aerogel stamps derived from double-network hydrogels. The stamp is then brought into contact with a substrate to be patterned under solvothermal reaction conditions inside an autoclave. The precursor ink forms liquid bridges between the topographic surface pattern of the stamp and the substrate. Evaporation-driven enrichment of the precursors in these liquid bridges, along with their liquid-bridge-guided conversion into the solvothermal reaction products, yields large-area submicron patterns of the solvothermal reaction products replicating the stamp topography. For example, we prepared thin hybrid films, which contained ordered monolayers of superparamagnetic submicron nickel ferrite dots prepared by solvothermal capillary stamping surrounded by nickel electrodeposited in a second orthogonal substrate functionalization step. The submicron nickel ferrite dots acted as a magnetic hardener, halving the remanence of the ferromagnetic nickel layer. In this way, thin-layer electromechanical systems, transformers, and positioning systems may be customized.

Phenolic Resin Dual-Use Stamps for Capillary Stamping and Decal Transfer Printing.

We report an optimized two-step thermopolymerization process carried out in contact with micropatterned molds that yields porous phenolic resin dual-use stamps with topographically micropatterned contact surfaces. With these stamps, two different parallel additive substrate manufacturing methods can be executed: capillary stamping and decal transfer microlithography. Under moderate contact pressures, the porous phenolic resin stamps are used for nondestructive ink transfer to substrates by capillary stamping. Continuous ink supply through the pore systems to the contact surfaces of the porous phenolic resin stamps enables multiple successive stamp-substrate contacts for lithographic ink deposition under ambient conditions. No deterioration of the quality of the deposited pattern occurs, and no interruptions for ink replenishment are required. Under a high contact pressure, porous phenolic resin stamps are used for decal transfer printing. In this way, the tips of the stamps' contact elements are lithographically transferred to counterpart substrates. The granular nature of the phenolic resin facilitates the rupture of the contact elements upon stamp retraction. The deposited phenolic resin micropatterns characterized by abundance of exposed hydroxyl groups are used as generic anchoring sites for further application-specific functionalizations. As an example, we deposited phenolic resin micropatterns on quartz crystal microbalance resonators and further functionalized them with polyethylenimine for preconcentration sensing of humidity and gaseous formic acid. We envision that also preconcentration coatings for other sensing methods, such as attenuated total reflection infrared spectroscopy and surface plasmon resonance spectroscopy, are accessible by this functionalization algorithm.

Flexible, Self-Supported Anode for Organic Batteries with a Matched Hierarchical Current Collector System for Boosted Current Density.

The inherent flexibility of redox-active organic polymers and carbon-based fillers, combined with flexible current collectors (CCs) is ideal for the fabrication of flexible batteries. Herein, a one-step electrophoretic deposition of polyviologen (PV)/graphene-oxide (GO) aqueous composites onto a flexible mesh of 60 µm thick wires, 100 µm apart, is described. Notably, during electrodeposition, GO is transformed into conductive reduced GO (rGO), and nanoscopic pores are formed by self-assembly allowing charge/discharge of the redox sites over dozens of micrometers. Typically, electrodeposition of PV alone on a flat CC (FCC) is limited by its electrically insulating structure to ≈0.15 mAh cm-2 , but the presence of rGO allows thicker active layers without loss in (dis-)charging kinetics and reaching areal capacities of ≈2 mAh cm-2 . Remarkably, when the FCC is replaced by a mesh, the deposition of significantly more anode materials (≈5 mAh cm-2 ) is possible, while the (dis-)charging kinetics is considerably improved. It exhibits high capacity retention at an ultrafast rate of 100 C (<3%) and excellent bending stabilities. This represents the first combination of a microscopic-CC (mesh wires) with a molecular-electronic and -ionic conductor (rGO with its pores), i.e., a hierarchical-CC system with maximized polymer thickness and minimized wire thickness. The stacking of such modified grids paves the road to further increase the areal capacity.

The Metallocene Battery: Ultrafast Electron Transfer Self Exchange Rate Accompanied by a Harmonic Height Breathing.

The first all-metallocene rechargeable battery consisting of poly-cobaltocenium/- and poly-ferrocene/reduced graphene oxide composites as anode and cathode was prepared. The intrinsically fast ET self-exchange rate of metallocenes was successfully combined with an efficient ion-percolation achieved by molecular self-assembly. The resulting battery materials show ideal Nernstian behavior, is thickness scalable up to >1.2 C cm-2 , and exhibit high coulombic efficiency at ultrafast rates (200 A g-1 ). Using aqueous LiClO4 , the charge is carried exclusively by the anion. The ClO4 - intercalation is accompanied by a reciprocal height change of the active layers. Principally, volume changes in organic battery materials during charging/discharging are not desirable and represent a major safety issue. However, here, the individual height changes-due to ion breathing-are reciprocal and thus prohibiting any internal pressure build-up in the closed-cell, leading to excellent cycling stability.

Electrochromic graduated filters with symmetric electrode configuration.

Graduated optical filters are commonly used for spatial image control as they are capable of darkening the overexposed parts of the image specifically. However, they lack flexibility because each filter has a fixed transmission distribution. We herein present a fully controllable graduated filter based on the electrochromic device. Its graduated transmission distribution can be spatially controlled by the application of multiple electric potentials. In this way, the control of the gradient's position and its width, transmission and angular orientation is possible. Simulation of both the spatial potential distribution and the resultant optical absorption distribution are conducted to optimize the electrode configuration and furthermore to derive a control dataset that facilitates the adjustment and thus the application of the graduated filter. Based on three objective and quantitative criteria, we identify the electrode configuration with the highest flexibility in all four controls, manufacture the device using a gravure printing process for the nanoparticle electrodes and show its successful application.

Active Anion Delivery by Self-Propelled Microswimmers.

Self-propelled micro- and nanomachines are at the forefront of materials research, branching into applications in biomedical science and environmental remediation. Cationic frameworks enabling the collection and delivery of anionic species (A-) are highly required, due to the large variety of life-threatening pollutants, such as radioactive technetium and carcinogenic chromium, and medicines, such as dexamethasone derivatives with negative charges. However, such autonomous moving carriers for active transport of the anions have been barely discussed. A polymeric viologen (PV++)-consisting of electroactive bicationic subunits-is utilized in a tubular autonomous microswimmer to selectively deliver A- of different sizes and charge densities. The cargo loading is based on a facile anion exchange mechanism. The packed crystal structure of PV++ allows removal of an exceptionally high quantity of anions per one microswimmer (2.55 × 10-13 mol anions per microswimmer), a critical factor often neglected regarding the real-world application of microswimmers. Notably, there was virtually no leakage of anions during the delivery process or upon keeping the loaded microswimmers under ambient conditions for at least 4 months. Multiple release mechanisms, compatible with different environments, including electrochemical, photochemical, and a metathesis reaction, with high efficiencies up to 98% are introduced. Such functional autonomous micromachines provide great promise for the next generation of functional materials for biomedical and environmental applications.

TED: A Tolerant Edit Distance for segmentation evaluation.

In this paper, we present a novel error measure to compare a computer-generated segmentation of images or volumes against ground truth. This measure, which we call Tolerant Edit Distance (TED), is motivated by two observations that we usually encounter in biomedical image processing: (1) Some errors, like small boundary shifts, are tolerable in practice. Which errors are tolerable is application dependent and should be explicitly expressible in the measure. (2) Non-tolerable errors have to be corrected manually. The effort needed to do so should be reflected by the error measure. Our measure is the minimal weighted sum of split and merge operations to apply to one segmentation such that it resembles another segmentation within specified tolerance bounds. This is in contrast to other commonly used measures like Rand index or variation of information, which integrate small, but tolerable, differences. Additionally, the TED provides intuitive numbers and allows the localization and classification of errors in images or volumes. We demonstrate the applicability of the TED on 3D segmentations of neurons in electron microscopy images where topological correctness is arguable more important than exact boundary locations. Furthermore, we show that the TED is not just limited to evaluation tasks. We use it as the loss function in a max-margin learning framework to find parameters of an automatic neuron segmentation algorithm. We show that training to minimize the TED, i.e., to minimize crucial errors, leads to higher segmentation accuracy compared to other learning methods.