Self-adaptive Scouting---Autonomous Experimentation for Systems Biology

We introduce a new algorithm for autonomous experimentation. This algorithm uses evolution to drive exploration during scientific discovery. Population size and mutation strength are self-adaptive. The only variables remaining to be set are the limits and maximum resolution of the parameters in the experiment. In practice, these are determined by instrumentation. Aside from conducting physical experiments, the algorithm is a valuable tool for investigating simulation models of biological systems. We illustrate the operation of the algorithm on a model of HIV-immune system interaction. Finally, the difference between scouting and optimization is discussed

Untersuchungen zum abriebpartikelinduzierten Zelltod mittels "live-cell Imaging" im Kontext der aseptischen Endoprothesenlockerung

Eine ungelöste Langzeitkomplikation der modernen Orthopädie stellt die aseptische, abriebpartikelinduzierte Endoprothesenlockerung dar. In diesem Kontext zeigen sich ursächlich neben Osteolysen und inflammatorischen Prozessen auch apoptotische Reaktionen der Abriebpartikel phagozytierenden Makrophagen. Die Verwendung eines Pan-Caspase-Inhibitors führte sowohl zu einer Minderung der Apoptose als auch der Osteolysen. Dies erschien paradox, da es sich bei der Apoptose im Gegensatz zur Nekrose um einen programmierten "protektiven" Zelltod handelt, der keine weiteren Zellschädigungen oder inflammatorischen Reaktionen auslöst. Ziel der vorliegenden Studie war es, den abriebpartikelinduzierten Zelltod zytomorphologisch genauer zu qualifizieren und quantifizieren. Insbesondere sollte evaluiert werden, ob der bei der Phagozytose von Abriebpartikeln entstehende Zellschrott, primär die Apoptotic Bodies (AB), weitere Zellschädigungen induzieren. THP-1 Zellen wurden zu makrophagenähnlichen Zellen (MLC) ausdifferenziert und in einer Cokultur mit Kobalt-Chrom- und Polyethylenabriebpartikeln inkubiert. Mittels cytomorphologischer Auswertung und einer Annexin-PI-Färbung erfolgte unter einem "live-Imaging" Fluoreszenzmikroskop die Detektion von Apoptose und Nekrose in Zeitraffer-Videos. Aus dem Überstand an apoptotischen Zellresten wurden anschließend die Apoptotic Bodies isoliert und unter gleichen Bedingungen erneut mit zu MLCs ausdifferenzierten THP-1 Zellen coinkubiert. Die Auswertung der Zeitrafferaufnahmen mit Abriebpartikeln zeigte einen signifikanten Anstieg der Zelltodrate durch Apoptose. Die isolierte Coinkubation von THP-1 MLCs mit ABs führte zu einer nochmaligen signifikanten Steigerung der Zelltodrate der phagozytierenden Zellen. Zudem zeigten sich anders als bei dem durch die Abriebpartikel induzierten Zelltod sowohl morphologisch als auch mittels Apoptose-Nekrose Färbung Eigenschaften des unkontrollierten nekrotischen Zelltodes. Die apoptotischen Zellreste, nicht jedoch die Abriebpartikel, lösen somit Übergangsformen der Apoptose und Nekrose aus, wie sie unlängst auch schon im Rahmen anderer Pathomechanismen beschrieben wurden. Die vorliegende Studie untermauert erstmalig die These, dass eine hohe primäre Apoptoserate oder ein fehlender Abbau der apoptotischen Zellreste einen Circulus vitiosus auslösen, der zu einem immer unkontrollierteren Zelltod führt. Dies erklärt, warum eine Hemmung der initialen Apoptose zu einer Verminderung der Osteolysen führt. Daraus lassen sich potenzielle pharmakologische Therapieoptionen wie z.B. die systemische Hemmung der Apoptose, die Optimierung der Clearance-Funktion der ABs (Adiponektin) oder der Einsatz immunmodulatorischer Substanzen (MTX, Biologicals) ableiten. Neben pharmakologischen Interventionen könnten auch Innovationen im Bereich der Materialforschung das zelltodinduzierende Potenzial der Abriebpartikel reduzieren

Competence-based Personnel Scheduling through Production Data

Personnel scheduling closes the missing link between personnel and production planning in manufacturing companies. Personnel scheduling has a significant impact on the development of employee competencies and the achievement of production goals. Nevertheless, in industrial practice the performance of the employee is not considered in production planning. According to the 5th Global Productivity Study of the Proudfoot Consulting 37% of working time is wasted, which is mainly due to a lack of planning and control. A major reason is the difficult measurability of employee competence and performance. In this paper, a method that describes the influence of employees on the processing and set-up time and its implementation at a manufacturer of thread parts is shown. For this, production data is statistically evaluated to predict the employee's influence. This information will be used by an algorithm for personnel scheduling. Thus, the highest possible competence development can be achieved in accordance with the utilization of the production. © 2017 The Authors. Published by Elsevier

Augmenting Milling Process Data for Shape Error Prediction

New integrated sensors and connected machine tools generate a tremendous amount of in-depth process data. The continuous transformation of the obtained data into deployable machining knowledge allows for faster ramp-ups, more reliable process outcome and higher profitability. A system for recording data from various sources - including a simultaneous material removal simulation - is implemented to aggregate and store process data. In addition to the simulation results, process data from the machine control, cutting forces and shape error samples are collected. A series of slot milling processes are carried out with varying cutting speed, feed per tooth and width of cut in a full factional design. In order to continuously evaluate process data, automatized methods are required. This is achieved using the simulation results to determine all relevant cutting conditions. Dependencies between cutting parameters, sensor signals and cutting result are identified and quantified. However, a one-dimensional model does not predict the shape error accurately. As an alternative model, a multidimensional model based on a Support Vector Machine is trained, using process forces and simulation data. The obtained prediction accuracy is significantly higher compared to the one-dimensional model and can be used to design highly reliable cutting processes.DFG/CRC/65

UV-Vis Spectra-Activated Droplet Sorting for Label-Free Chemical Identification and Collection of Drople

We introduce the UV-vis spectra-activated droplet sorter (UVADS) for high-throughput label-free chemical identification and enzyme screening. In contrast to previous absorbance-based droplet sorters that relied on single-wavelength absorbance in the visible range, our platform collects full UV-vis spectra from 200 to 1050 nm at up to 2100 spectra per second. Our custom-built open-source software application, "SpectraSorter," enables real-time data processing, analysis, visualization, and selection of droplets for sorting with any set of UV-vis spectral features. An optimized UV-vis detection region extended the absorbance path length for droplets and allowed for the direct protein quantification down to 10 μM of bovine serum albumin at 280 nm. UV-vis spectral data can distinguish a variety of different chemicals or spurious events (such as air bubbles) that are inaccessible at a single wavelength. The platform is used to measure ergothionase enzyme activity from monoclonal microcolonies isolated in droplets. In a label-free manner, we directly measure the ergothioneine substrate to thiourocanic acid product conversion while tracking the microcolony formation. UVADS represents an important new tool for high-throughput label-free in-droplet chemical analysi

Growth and aging in a few phase-separating active matter systems

Via computer simulations we study evolution dynamics in systems of continuously moving Active Brownian Particles. The obtained results are discussed against those from the passive 2D Ising case. Following sudden quenches of uniform configurations to state points lying within the miscibility gaps and to the critical points, we investigate the far-from-steady-state dynamics by calculating quantities associated with structure and characteristic length scales. We also study aging for quenches into the miscibility gap and provide a quantitative picture for the scaling behavior of the two-time order-parameter correlation function. The overall structure and dynamics are consistent with expectations from the Ising model. This remains true for certain active lattice models as well for which we present results for quenches to the critical points.Comment: 9 pages, 11 figure