3D organotypic cultures of human HepaRG cells: a tool for in vitro toxicity studies.

in Toxicological sciences : an official journal of the Society of Toxicology (2013), 133(1), 67-78

Drug-induced human hepatotoxicity is difficult to predict using the current in vitro systems. In this study, long-term 3D organotypic cultures of the human hepatoma HepaRG cell line were prepared using a ... [more ▼]

Drug-induced human hepatotoxicity is difficult to predict using the current in vitro systems. In this study, long-term 3D organotypic cultures of the human hepatoma HepaRG cell line were prepared using a high-throughput hanging drop method. The organotypic cultures were maintained for 3 weeks and assessed for (1) liver specific functions, including phase I enzyme and transporter activities, (2) expression of liver-specific proteins, and (3) responses to three drugs (acetaminophen, troglitazone, and rosiglitazone). Our results show that the organotypic cultures maintain high liver-specific functionality during 3 weeks of culture. The immunohistochemistry analyses illustrate that the organotypic cultures express liver-specific markers such as albumin, CYP3A4, CYP2E1, and MRP-2 throughout the cultivation period. Accordingly, the production rates of albumin and glucose, as well as CYP2E1 activity, were significantly higher in the 3D versus the 2D cultures. Toxicity studies show that the organotypic cultures are more sensitive to acetaminophen- and rosiglitazone-induced toxicity but less sensitive to troglitazone-induced toxicity than the 2D cultures. Furthermore, the EC50 value (2.7mM) for acetaminophen on the 3D cultures was similar to in vivo toxicity. In summary, the results from our study suggest that the 3D organotypic HepaRG culture is a promising in vitro tool for more accurate assessment of acute and also possibly for chronic drug-induced hepatotoxicity. [less ▲]

3D pose estimation based on planar object tracking for UAVs control

in Proccedings of IEEE International Conference on Robotics and Automation (ICRA) (2010)

This article presents a real time Unmanned Aerial Vehicles UAVs 3D pose estimation method using planar object tracking, in order to be used on the control system of a UAV. The method explodes the rich ... [more ▼]

This article presents a real time Unmanned Aerial Vehicles UAVs 3D pose estimation method using planar object tracking, in order to be used on the control system of a UAV. The method explodes the rich information obtained by a projective transformation of planar objects on a calibrated camera. The algorithm obtains the metric and projective components of a reference object (landmark or helipad) with respect to the UAV camera coordinate system, using a robust real time object tracking based on homographies. The algorithm is validated on real flights that compare the estimated data against that obtained by the inertial measurement unit IMU, showing that the proposed method robustly estimates the helicopter's 3D position with respect to a reference landmark, with a high quality on the position and orientation estimation when the aircraft is flying at low altitudes, a situation in which the GPS information is often inaccurate. The obtained results indicate that the proposed algorithm is suitable for complex control tasks, such as autonomous landing, accurate low altitude positioning and dropping of payloads. [less ▲]

3D real-time human action recognition using a spline interpolation approach

in 2015 International Conference on Image Processing Theory, Tools and Applications (IPTA) (2015)

A 3D shear material damping model for man-made vibrations of the ground

in 13th Baltic Sea Region Geotechnical Conference (2016, September)

Man-made vibrations from different types of sources are usually measured on the surface of the ground or building. The measured signal is always the superposition of all travelling basic waves. For a ... [more ▼]

Man-made vibrations from different types of sources are usually measured on the surface of the ground or building. The measured signal is always the superposition of all travelling basic waves. For a homogeneous half space there are three basic waves – the Compressional (P-wave), Shear (S-wave) and Rayleigh wave (R-wave). Depending on the measuring equipment, only the accelerations or velocities in time of the superposed wave can be measured, but not the distribution of the individual basic waves. Additional problems are that each of the basic waves has its own velocity, besides the body and surface waves have different attenuation laws. By using the rules of superposition of harmonic waves and also the propagation laws of the P-, S- and R-waves, it should be theoretically possible to split the measured superposed signal into the basic waves, because mathematically a system of equations can be assembled which describes the displacements at multiple measuring points in time. In this paper this problem has been solved for a homogenous, elastic and isotropic soil, which is disturbed by a harmonically oscillating disc on the surface. A numerical simulation was performed using a finite element method. The displacements in time were recorded in 10 points on the surface and a system of superposed equations was assembled and solved. The findings prove that each of the three basic waves has its own phase shift with the source, something which was not known before. [less ▲]

3D Time-Of-Flight Camera System and Position/Orientation Calibration Method Therefor

Patent (2011)

3D visualization of archaeological uncertainty

in Proc. ACM Symposium on Applied Perception (2010)

By uncertainty, we define an archaeological expert's level of confidence in an interpretation deriving from gathered evidence. Archaeologists and computer scientists have urged caution in the use of 3D ... [more ▼]

By uncertainty, we define an archaeological expert's level of confidence in an interpretation deriving from gathered evidence. Archaeologists and computer scientists have urged caution in the use of 3D for archaeological reconstructions because the availability of other possible hypotheses is not always being acknowledged. This poster presents a 3D visualization system of archaeological uncertainty. [less ▲]

3DBodyTex: Textured 3D Body Dataset

in 2018 Sixth International Conference on 3D Vision (3DV 2018) (2018)

In this paper, a dataset, named 3DBodyTex, of static 3D body scans with high-quality texture information is presented along with a fully automatic method for body model fitting to a 3D scan. 3D shape ... [more ▼]

In this paper, a dataset, named 3DBodyTex, of static 3D body scans with high-quality texture information is presented along with a fully automatic method for body model fitting to a 3D scan. 3D shape modelling is a fundamental area of computer vision that has a wide range of applications in the industry. It is becoming even more important as 3D sensing technologies are entering consumer devices such as smartphones. As the main output of these sensors is the 3D shape, many methods rely on this information alone. The 3D shape information is, however, very high dimensional and leads to models that must handle many degrees of freedom from limited information. Coupling texture and 3D shape alleviates this burden, as the texture of 3D objects is complementary to their shape. Unfortunately, high-quality texture content is lacking from commonly available datasets, and in particular in datasets of 3D body scans. The proposed 3DBodyTex dataset aims to fill this gap with hundreds of high-quality 3D body scans with high-resolution texture. Moreover, a novel fully automatic pipeline to fit a body model to a 3D scan is proposed. It includes a robust 3D landmark estimator that takes advantage of the high-resolution texture of 3DBodyTex. The pipeline is applied to the scans, and the results are reported and discussed, showcasing the diversity of the features in the dataset. [less ▲]

§ 4 WpHG zur Zuständigkeit der Bundesanstalt für Finanzdienstleistungsaufsicht, Kapitalmarktrechtskommentar

in Schwark, E.; Zimmer, D. (Eds.) Kapitalmarktrechtskommentar (2010)

4. Forschungsbericht zur Weiterentwicklung des Arbeitsqualitätsindexes in Luxemburg

E-print/Working paper (2019)

Der Survey zu dem „Quality of Work Index Luxembourg“ (QoW), der von der Universität Luxemburg und der luxemburgischen Chambré des Salariés entwickelt wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015 ... [more ▼]

Der Survey zu dem „Quality of Work Index Luxembourg“ (QoW), der von der Universität Luxemburg und der luxemburgischen Chambré des Salariés entwickelt wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015, 2016, 2017), wurde 2017 bereits zum fünften Mal mittels einer telefonischen Befragung durchgeführt. Ziel des Index ist es, die erlebte Arbeitssituation und -qualität luxemburgischer Arbeitnehmer zu erfassen. Der vorliegende Bericht dokumentiert die psychometrische Testung der Güte des aktuellen Erhebungsinstruments. Dazu erfolgt zunächst eine Beschreibung der für die Skalen genutzten Items, die Überprüfung der internen Konsistenz der jeweiligen Skala mittels verschiedener Reliabilitätsstatistiken (Cronbach’s Alpha, Korrelationsanalysen der Items) sowie Koeffizienten zur Beschreibung der Skalenverteilung. Konfirmatorische Faktorenanalysen dienen dazu, zu testen, ob die Items auf den a priori festgelegten Faktoren laden und ob sich die unterstellte Faktorenstruktur auch in den Daten zeigt. Außerdem werden die Zusammenhänge der Skalen mittels Korrelationsanalysen über-prüft. Die QoW-Skalen werden außerdem auf verschiedene Well-Being-Skalen regressiert, um deren Relevanz für den QoW-Index zu prüfen. Da der QoW Survey teilweise als Panelbefragung durchgeführt wird, wird außerdem geklärt, ob es hinsichtlich demographischer Eigenschaften der Befragten, hinsichtlich der QoW-Skalen oder hinsichtlich verschiedener Well-Being-Maße zu systematischen Ausfällen seit der letzten Welle gekommen ist. Ebenso werden einige Längsschnitt-Regressionsanalysen gerechnet, um zu überprüfen, ob einige Arbeitsbedingungen längerfristige Effekte auf das Well-Being der Arbeitnehmer aufweisen. Die QoW-Befragung 2017 hat außerdem das Schwerpunktthema „Digitalisierung“ behandelt. Die Themenblöcke werden mittels Latenter Profile-Analysen untersucht. Im Anschluss wird überprüft ob sich die extrahierten Profile hinsichtlich der QoW- und der Well-Being-Skalen unterscheiden. Abschließend wird das gesamte Erhebungsinstrument zusammenfassend diskutiert und Empfehlungen bezüglich der weiteren Entwicklung der Skalen gegeben. [less ▲]

40 editions of ICSE: the ruby anniversary celebration

Book published by self-published (2018)