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Designing experiments which delocalize ever more complex and more massive particles requires a quantitative assessment of new interferometer configurations. Here, we introduce a figure of
merit which quantifies the difference between a genuine quantum interference pattern and a classical shadow and use it to compare a number of near-field interferometer schemes. This allows us to identify the most promising setups for future tests of the quantum superposition principle, and to discuss the perspectives of interferometry with complex molecules and clusters.
Respiratory diseases are characterised by high prevalence among the European population. Medical aerosol inhalers are the most commonly used means of drug delivery into the human respiratory system. This paper focuses on characteristic waveforms that can be utilised during aerosol deposition studies to simulate conditions of rapid human inhalation. Additionally, an inhalatory waveform based on clinically recorded spirometry data is introduced. Experimental measurements are performed and simulation results mutually compared using the electro-mechanical lung simulator xPULM. The inhalatory waveforms are repeatably simulated with high fidelity in regards to the waveform shape with the lowest value of the Goodness of fit 0.89. Additionally, the measured values for all characteristic inhalatory parameters are simulated with low standard deviation < 1. The differences between the required and measured waveform shapes are small, < 3 L/min and do not influence the overall inhalatory volume. This opens a possibility of utilising the xPULM for medical aerosol inhalers testing.
Changes of particle deposition caused by different breathing patterns during active lung simulation
(2019)
Aerosols are an integral part of everyday life and as such are inhaled under various conditions and circumstances. These may vary based on the health and activity status of an individual. The aim of this work is to analyse the particle deposition mechanisms during the simulation of three different breathing patterns using an aerosol representing the PM1 fraction of fine particles. The active electro-mechanical lung simulator xPULM is utilized as a driving force and is combined with a non-invasive direct reading optical aerosol measurement system. Results show differences between the number of deposited particles for the three breathing patterns and for the three typical size ranges of airborne particles. Overall, the presented approach demonstrates the possibility of determining the changes of aerosol uptake based on different breathing patterns using the electro-mechanical lung simulator and laboratory produced aerosols. Further measurement cycles must be performed in order to validate the found interactions and to characterize the major influencing parameters.
Presentation of successful use of IHE profiles in national strategies (Austria and Switzerland)
(2019)
Changes of particle deposition caused by different breathing patterns during active lung simulation
(2019)
Simulation models in respiratory research are increasingly used for medical product development and testing, especially because in-vivo models are coupled with a high degree of complexity and ethical concerns. This work introduces a respiratory simulation system, which is bridging the gap between the complex, real anatomical environment and the safe, cost-effective simulation methods. The presented electro-mechanical lung simulator, xPULM, combines in-silico, ex-vivo and mechanical respiratory approaches by realistically replicating an actively breathing human lung. The reproducibility of sinusoidal breathing simulations with xPULM was verified for selected breathing frequencies (10–18 bpm) and tidal volumes (400–600 ml) physiologically occurring during human breathing at rest. Human lung anatomy was modelled using latex bags and primed porcine lungs. High reproducibility of flow and pressure characteristics was shown by evaluating breathing cycles (nTotal = 3273) with highest standard deviation |3σ| for both, simplified lung equivalents (μV˙ = 23.98 ± 1.04 l/min, μP = −0.78 ± 0.63 hPa) and primed porcine lungs (μV˙ = 18.87 ± 2.49 l/min, μP = −21.13 ± 1.47 hPa). The adaptability of the breathing simulation parameters, coupled with the use of porcine lungs salvaged from a slaughterhouse process, represents an advancement towards anatomically and physiologically realistic modelling of human respiration.
Repopulation of an auricular cartilage scaffold, AuriScaff, perforated with an enzyme combination
(2019)
Biomaterials currently in use for articular cartilage regeneration do not mimic the composition or architecture of hyaline cartilage, leading to the formation of repair tissue with inferior characteristics. In this study we demonstrate the use of "AuriScaff", an enzymatically perforated bovine auricular cartilage scaffold, as a novel biomaterial for repopulation with regenerative cells and for the formation of high-quality hyaline cartilage. AuriScaff features a traversing channel network, generated by selective depletion of elastic fibers, enabling uniform repopulation with therapeutic cells. The complex collagen type II matrix is left intact, as observed by immunohistochemistry, SEM and TEM. The compressive modulus is diminished, but three times higher than in the clinically used collagen type I/III scaffold that served as control. Seeding tests with human articular chondrocytes (hAC) alone and in co-culture with human adipose-derived stromal/stem cells (ASC) confirmed that the network enabled cell migration throughout the scaffold. It also guides collagen alignment along the channels and, due to the generally traverse channel alignment, newly deposited cartilage matrix corresponds with the orientation of collagen within articular cartilage. In an osteochondral plug model, AuriScaff filled the complete defect with compact collagen type II matrix and enabled chondrogenic differentiation inside the channels. Using adult articular chondrocytes from bovine origin (bAC), filling of even deep defects with high-quality hyaline-like cartilage was achieved after 6 weeks in vivo. With its composition and spatial organization, AuriScaff provides an optimal chondrogenic environment for therapeutic cells to treat cartilage defects and is expected to improve long-term outcome by channel-guided repopulation followed by matrix deposition and alignment. STATEMENT OF SIGNIFICANCE: After two decades of tissue engineering for cartilage regeneration, there is still no optimal strategy available to overcome problems such as inconsistent clinical outcome, early and late graft failures. Especially large defects are dependent on biomaterials and their scaffolding, guiding and protective function. Considering the currently used biomaterials, structure and mechanical properties appear to be insufficient to fulfill this task. The novel scaffold developed within this study is the first approach enabling the use of dense cartilage matrix, repopulate it via channels and provide the cells with a compact collagen type II environment. Due to its density, it also provides better mechanical properties than materials currently used in clinics. We therefore think, that the auricular cartilage scaffold (AuriScaff) has a high potential to improve future cartilage regeneration approaches.
The prerequisite for a successful clinical use of autologous adipose-tissue-derived cells is the highest possible regenerative potential of the applied cell population, the stromal vascular fraction (SVF). Current isolation methods depend on high enzyme concentration, lysis buffer, long incubation steps and mechanical stress, resulting in single cell dissociation. The aim of the study was to limit cell manipulation and obtain a derivative comprising therapeutic cells (microtissue-SVF) without dissociation from their natural extracellular matrix, by employing a gentle good manufacturing practice (GMP)-grade isolation. The microtissue-SVF yielded larger numbers of viable cells as compared to the improved standard-SVF, both with low enzyme concentration and minimal dead cell content. It comprised stromal tissue compounds (collagen, glycosaminoglycans, fibroblasts), capillaries and vessel structures (CD31+, smooth muscle actin+). A broad range of cell types was identified by surface-marker characterisation, including mesenchymal, haematopoietic, pericytic, blood and lymphatic vascular and epithelial cells. Subpopulations such as supra-adventitial adipose-derived stromal/stem cells and endothelial progenitor cells were significantly more abundant in the microtissue-SVF, corroborated by significantly higher potency for angiogenic tube-like structure formation in vitro. The microtissue-SVF showed the characteristic phenotype and tri-lineage mesenchymal differentiation potential in vitro and an immunomodulatory and pro-angiogenic secretome. In vivo implantation of the microtissue-SVF combined with fat demonstrated successful graft integration in nude mice. The present study demonstrated a fast and gentle isolation by minor manipulation of liposuction material, achieving a therapeutically relevant cell population with high vascularisation potential and immunomodulatory properties still embedded in a fraction of its original matrix.
Four quadratic DC/DC converters with one low-side switch and a tapped inductor at the input side
(2019)
Der Einsatz von Lernvideos ist aus zeitgemäßer Lehre kaum noch wegzudenken. Um adäquates, fachlich und didaktisch abgestimmtes Lehr-und Lernmaterial mit angemessenem Ressourcenaufwand zu ermöglichen, ist es für Hochschulen und fachliche ExpertInnen ein sinnvoller Weg, selbst Lehrvideos zu produzieren. Dieser Beitrag stellt ein Beispiel guter Praxis im Aufbau und Betrieb eines E-Learning Labors vor. Dabei werden die Infrastruktur und Technik, das Produktions-Prozedere sowie mediendidaktische und rechtliche Aspekte beleuchtet.
Driver disregard for the minimum safety distance increases the probability of rear-end collisions. In order to contribute to active safety on the road, we propose in this work a low-cost Forward Collision Warning system that captures and processes images. Using cameras located in the rear section of a leading vehicle, this system serves the purpose of discouraging tailgating behavior from the vehicle driving behind. We perform in this paper the pertinent field tests to assess system performance, focusing on the calculated distance from the processing of images and the error margins in a straight line, as well as in a curve. Based on the evaluation results, the current version of the Tailigator can be used at speeds up to 50 km per hour without any restrictions. The measurements showed similar characteristics both on the straight line and in the curve. At close distances, between 3 and 5 m, the values deviated from the real value. At average distances, around 10 to 15 m, the Tailigator achieved the best results. From distances higher than 20 m, the deviations increased steadily with the distance. We contribute to the state of the art with an innovative low-cost system to identify tailgating behavior and raise awareness, which works independently of the rear vehicle's communication capabilities or equipment.
The Evaluation of the Work-integrated Computer Science Degree Program at the UAS Technikum Wien
(2019)
This review article summarizes the state of the art in energy efficiency (EE) management in air and rail cargo transportation. After an introduction, explanations and definitions follow around the topic of energy efficiency. The political framework conditions of the European Union (EU) as well as the associated European Union Emissions Trading System are described. In particular, the drive technologies, CO2 emissions, and fuel-saving options are reviewed.
Methodik zur Entwicklung sicherer kollaborativer Produktionssysteme im Rahmen von Industrie 4.0
(2019)
Bridging Diversity
(2019)
Didaktik
(2019)
Praxisbezug der Hochschullehre – dargestellt am Beispiel des österreichischen Fachhochschul-Sektors
(2019)
Performance and Reliability Aspects of Clock Synchronization Techniques for Industrial Automation
(2019)
GREISSLER.PLUS: Towards a Modern Distribution of Regional Goods in Rural Areas in the Digital Era
(2019)
Smart Textiles in Wound Care: Functionalization of Cotton/PET Blends with Antimicrobial Nanocapsules
(2019)
Effect of fluid dynamics on decellularization efficacy and mechanical properties of blood vessels.
(2019)
Osteointegration of a Novel Silk Fiber-Based ACL Scaffold by Formation of a Ligament-Bone Interface.
(2019)
Cyberphysical production systems are an important part of today’s manufacturing process. The ever-growing need of highly optimized,
i.e. at the same time flexible and ecient systems, requires the use of not only appropriate machines, but as well a
communication framework and data model that is manufacturer independent and scalable. This paper proposes a communicationframework
based on OPC UA that employs an agent-based architecture. The proposed system has been implemented and tested in
the Digital Factory of the UAS Technikum Wien. It shows promising behavior within distributed manufacturing systems.
Repopulation of an auricular cartilage scaffold, AuriScaff, perforated with an enzyme combination.
(2019)
Iodine-Enhanced Micro-CT Imaging of Soft Tissue on the Example of Peripheral Nerve Regeneration
(2019)
In an effort to broaden the engineering applications of material extrusion based additive manufacturing (MEAM), new materials are being developed. Adding carbon-fibers (CF) has been one strategy to increase the mechanical performance of different thermoplastics. One challenge is to determine the amount of CF needed to increase the mechanical performance without affecting the “printability” of the compounds. In this paper, different amounts (10, 15, and 20 vol.%) of CF were added to recycled polypropylene (rPP) and polyamide 12 (PA12). A compatibilizer was used for rPP, but not for PA12. Filaments for MEAM were extruded from the different compounds and the viscosity as well as the tensile properties were measured and compared to the processed polymeric matrices. It was observed that the viscosities at the angular frequencies relevant for MEAM (100 to 200 rad/s) were not significantly different for rPP+CF compounds, but it was higher for PA12+CF compounds. As expected, the elongation at break significantly decreased with the addition of CF for all compounds. For the composites with an rPP matrix, the Young’s modulus and the ultimate tensile strength (UTS) continuously increased as the CF content increased to 20 vol.%. For PA12-based materials, the Young’s modulus and the UTS increased with CF content, but adding more than 15 vol.% did not further improve these values. Therefore, it was concluded that for PA12 the maximum amount of CF that should be added was 15 vol.%. Using scanning electron microscopy, it was observed that the CF were homogeneously dispersed in the rPP matrix, but not so well in the PA12 matrix, with fibers being more concentrated towards the rim of the filament. Finally, filaments of rPP, rPP+20CF, PA12 and PA12+15CF were used to print complex geometries by means of MEAM, and it was observed that CF helped to reduce the warpage compared to the unfilled filaments. A potential application of this phenomenon could be the reduction of the bed temperature to develop a more energy efficient MEAM process for semi-crystalline polymers.