Since the introduction of rental E-scooters in Germany in mid-June 2019, the safety of this new means of transport has been the subject of extensive public debate. However, valid data on injuries and usage habits are not yet available. This retrospective two-center study included a total of 76 patients who presented to the emergency department following E-scooter-related accidents. The mean age was 34.3 ± 12.4 years and 69.7% of the patients were male. About half of the patients were admitted by ambulance (42.1%). Fractures were found in 48.6% of patients, and 27.6% required surgical treatment due to a fracture. The upper extremities were the most commonly affected body region, followed by injuries to the lower extremity and to the head and face. Only one patient had worn a helmet. In-hospital treatment was necessary for 26.3% of the cases. Patients presented to the emergency department mainly during the weekend and on-call times. This is the first report on E-scooter-related injuries in Germany. Accidents with E-scooters can cause serious injuries and, therefore, represent a further burden to emergency departments. The use of E-scooters appears to be mostly recreational, and the rate of use of protective gear is low.

Biofilm growth has been observed in Soviet/Russian (Salyuts and Mir), American (Skylab), and International (ISS) Space Stations, sometimes jeopardizing key equipment like spacesuits, water recycling units, radiators, and navigation windows. Biofilm formation also increases the risk of human illnesses and therefore needs to be well understood to enable safe, long-duration, human space missions. Here, the design of a NASA-supported biofilm in space project is reported. This new project aims to characterize biofilm inside the International Space Station in a controlled fashion, assessing changes in mass, thickness, and morphology. The space-based experiment also aims at elucidating the biomechanical and transcriptomic mechanisms involved in the formation of a “column-and-canopy” biofilm architecture that has previously been observed in space. To search for potential solutions, different materials and surface topologies will be used as the substrata for microbial growth. The adhesion of bacteria to surfaces and therefore the initial biofilm formation is strongly governed by topographical surface features of about the bacterial scale. Thus, using Direct Laser-Interference Patterning, some material coupons will have surface patterns with periodicities equal, above or below the size of bacteria. Additionally, a novel lubricant-impregnated surface will be assessed for potential Earth and spaceflight anti-biofilm applications. This paper describes the current experiment design including microbial strains and substrata materials and nanotopographies being considered, constraints and limitations that arise from performing experiments in space, and the next steps needed to mature the design to be spaceflight-ready.

Surface structures in the micro-and nanometre length scale exert a major influence on performance and functionality for many specialized applications in surface engineering. However, they are often limited to certain pattern scales and materials, depending on which processing technique is used. Likewise, the morphology of the topography is in complex relation to the utilized processing methodology. in this study, the generation of hierarchical surface structures in the micro-as well as the sub-micrometre scale was achieved on ceramic, polymer and metallic materials by utilizing Ultrashort pulsed Direct Laser interference patterning (USp-DLip). the morphologies of the generated patterns where examined in relation to the unique physical interaction of each material with ultrashort pulsed laser irradiation. In this context, the pattern formation on copper, CuZn37 brass and AISI 304 stainless steel was investigated in detail by means of a combination of experiment and simulation to understand the individual thermal interactions involved in USp-DLip processing. thereby, the pattern's hierarchical topography could be tailored besides achieving higher process control in the production of patterns in the sub-µm range by USp-DLip. Highly specific surface properties in nature, like the well-known lotus and shark skin effects, are closely related to surface structures in the micrometre and nanometre length scale, often involving hierarchical patterns 1. In fact, such biomimetic surface patterns have already proven to provide unique properties in several technical systems including the manipulation of contact mechanics and optical properties like light diffraction and absorption 2-4. Patterns on the threshold between the micro-and the nanometre scale also showed to provide promising surface properties for medical products, as they can tailor the adhesion of both, cells and germs 5-7. In this context, current research projects investigate the intricacies to prevent biofilm formation by surface patterning of different solid materials on the International Space Station (ISS), which endanger its crew in terms of both, health and damage to critical components 8. The predominant impact on the unique properties of patterned surfaces is defined by the scale and morphology of the surface features also including sub-patterns, which have to be adjusted specifically for each application. For instance, in antibacterial applications, feature sizes in the sub-µm length scale showed to be most effective against bacterial adhesion 7-10. The processing methodology, dealing with such delicate surface modification, needs to ensure high machining precision as well as processing speeds and costs, which are able to compete with the classical methods of surface engineering. Besides lithographic methods, laser interference-based techniques have proven their worth in generating precise surface patterns, as they provide high processing speeds with little to no need for preparation and post-processing 11. Direct Laser Interference Patterning (DLIP) usi...

Current estimates by the World Health Organization (WHO) suggest that the number of deaths caused by multidrug-resistant bacteria worldwide could rise to ten million per year by 2050, if the current trend continues. [2] One way to fight both critical biofilm formation as well as the spreading of infectious diseases is to reduce the survivability of bacteria on technically and frequently touched contact surfaces, by using actively antimicrobial materials like copper (Cu) and silver (Ag) that are not based on pharmaceutical antibiotics. Here, Cu shows great potential for a wider application, [3,4] looking back to a multi-millennial history of repeated rediscovery of its aseptic properties, [5] while it is also involved as a trace element in central processes of human metabolism. [6] In contrast, Ag exhibits toxicity at low quantities, [7] by which dosing has to be precisely adjusted in case of antimicrobial application to avoid a negative immune response. [8] Due to the toxic effect of released Cu ions, bacteria [9,10] as well as viruses [11] are rapidly killed in both dry and moist environments, when adhering to Cu surfaces. The antimicrobial properties of Cu are closely linked to both the amount of ions released and absorbed by the attacked microorganism, whereby specific effects have to be considered when using Cu as an antimicrobial agent: 1) It Copper (Cu) exhibits great potential for application in the design of antimicrobial contact surfaces aiming to reduce pathogenic contamination in public areas as well as clinically critical environments. However, current application perspectives rely purely on the toxic effect of emitted Cu ions, without considering influences on the interaction of pathogenic microorganisms with the surface to enhance antimicrobial efficiency. In this study, it is investigated on how antibacterial properties of Cu surfaces against Escherichia coli can be increased by tailored functionalization of the substrate surface by means of ultrashort pulsed direct laser interference patterning (USP-DLIP). Surface patterns in the scale range of single bacteria cells are fabricated to purposefully increase bacteria/surface contact area, while parallel modification of the surface chemistry allows to involve the aspect of surface wettability into bacterial attachment and the resulting antibacterial effectivity. The results exhibit a delicate interplay between bacterial adhesion and the expression of antibacterial properties, where a reduction of bacterial cell viability of up to 15-fold can be achieved for E. coli on USP-DLIP surfaces in comparison to smooth Cu surfaces. Thereby, it can be shown how the antimicrobial properties of copper surfaces can be additionally enhanced by targeted surface functionalization.

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Surface patterning in the micro- and nanometer-range by means of pulsed laser interference has repeatedly proven to be a versatile tool for surface functionalization. With these techniques, however, the surface is often changed not only in terms of morphology but also in terms of surface chemistry. In this study, we present an in-depth investigation of the chemical surface modification occurring during surface patterning of copper by ultrashort pulsed direct laser interference patterning (USP-DLIP). A multimethod approach of parallel analysis using visualizing, topography-sensitive, and spectroscopic techniques allowed a detailed quantification of surface morphology as well as composition and distribution of surface chemistry related to both processing and atmospheric aging. The investigations revealed a heterogeneous surface composition separated in peak and valley regions predominantly consisting of Cu2O, as well as superficial agglomerations of CuO and carbon species. The evaluation was supported by a modeling approach for the quantification of XPS results in relation to heterogeneous surface composition, which was observed by means of a combination of different spectroscopic techniques. The overall results provide a detailed understanding of the chemical and topographical surface modification during USP-DLIP, which allows a more targeted use of this technology for surface functionalization.

The population of industrialized countries such as the United States or of countries from the European Union spends approximately more than one hour each day in vehicles. In this respect, numerous studies have so far addressed outdoor air pollution that arises from traffic. By contrast, only little is known about indoor air quality in vehicles and influences by non-vehicle sources.Therefore the present article aims to summarize recent studies that address i.e. particulate matter exposure. It can be stated that although there is a large amount of data present for outdoor air pollution, research in the area of indoor air quality in vehicles is still limited. Especially, knowledge on non-vehicular sources is missing. In this respect, an understanding of the effects and interactions of i.e. tobacco smoke under realistic automobile conditions should be achieved in future.

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