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This summer, RoboCup competitions were held for the 20th time in Leipzig, Germany. It was the second time that RoboCup took place in Germany, 10 years after the 2006 RoboCup in Bremen. In this article, we give an overview on the latest developments of RoboCup and what happened in the different leagues over the last decade. With its 20th edition, RoboCup clearly is a success story and a role model for robotics competitions. From our personal view point, we acknowledge this by giving a retrospection about what makes RoboCup such a success.
Robots are widely used as a vehicle to spark interest in science and technology in learners. A number of initiatives focus on this issue, for instance, the Roberta Initiative, the FIRST Lego League, the World Robot Olympiad and RoboCup Junior. Robotic competitions are valuable not only for school learners but also for university students, as the RoboCup initiative shows. Besides technical skills, the students get some project exposure and experience what it means to finish their tasks on time. But qualifying students for future high-tech areas should not only be for students from developed countries. In this article, we present our experiences with research and education in robotics within the RoboCup initiative, in Germany and South Africa; we report on our experiences with trying to get the RoboCup initiative in South Africa going. RoboCup has a huge support base of academic institutions in Germany; this is not the case in South Africa. We present our ‘north–south’ collaboration initiatives in RoboCup between Germany and South Africa and discuss some of the reasons why we think it is harder to run RoboCup in South Africa.
Electromicrobial engineering is an emerging, highly interdisciplinary research area linking bioprocesses with electrochemistry. In this work, microbial electrosynthesis (MES) of biobutanol is carried out during acetone-butanol-ethanol (ABE) fermentations with Clostridium acetobutylicum. A constant electric potential of −600mV (vs. Ag/AgCl) with simultaneous addition of the soluble redox mediator neutral red is used in order to study the electron transfer between the working electrode and the bacterial cells. The results show an earlier initiation of solvent production for all fermentations with applied potential compared to the conventional ABE fermentation. The f inal butanol concentration can be more than doubled by the application of a negative potential combined with addition of neutral red. Moreover a higher biofilm formation on the working electrode compared to control cultivations has been observed. In contrast to previous studies, our results also indicate that direct electron transfer (DET) might be possible with C. acetobutylicum. The presented results make microbial butanol production economically attractive and therefore support the development of sustainable production processes in the chemical industry aspired by the “Centre for resource-efficient chemistry and raw material change” as well as the the project “NanoKat” working on nanostructured catalysts in Kaiserslautern.
In den letzten Jahren haben nachhaltige, biotechnologische Prozesse zunehmend an Bedeutung gewonnen. Die Aceton-Butanol-Ethanol-Fermentation (ABE-Fermentation) mit dem anaeroben Bakterium Clostridium acetobutylicum zur Gewinnung von Biobutanol könnte in diesem Zusammenhang eine Möglichkeit der nachhaltigen Kraftstoffproduktion darstellen. In dieser Arbeit wird der Einfluss zusätzlich verfügbarer Elektronen durch den Einsatz des Phenazin-Farbstoffs Neutralrot als Redoxmediator sowie das Anlegen eines elektrischen Potenzials während der ABE-Fermentation untersucht. Es wird gezeigt, dass das Neutralrot keinen Einfluss auf die Leerlaufspannung von ca. 500 mV vs. Ag/AgCl während der Fermentation hat. Der Mediator bewirkt allerdings eine frühere Butanolbildung sowie höhere Butanolkonzentrationen. Wird zudem die Mediatorkonzentration von 125 mM auf 250 mM angehoben, wird dabei auch die maximale Butanolkonzentration um 36 % ± 1,8 % innerhalb von28 Stunden gesteigert.
Based on an identifying Volterra type integral equation for randomly right censored observations from a lifetime distribution function F, we solve the corresponding estimating equation by an explicit and implicit Euler scheme. While the first approach results in some known estimators, the second one produces new semi-parametric and pre-smoothed Kaplan–Meier estimators which are real distribution functions rather than sub-distribution functions as the former ones are. This property of the new estimators is particular useful if one wants to estimate the expected lifetime restricted to the support of the observation time.
Specifically, we focus on estimation under the semi-parametric random censorship model (SRCM), that is, a random censorship model where the conditional expectation of the censoring indicator given the observation belongs to a parametric family. We show that some estimated linear functionals which are based on the new semi-parametric estimator are strong consistent, asymptotically normal, and efficient under SRCM. In a small simulation study, the performance of the new estimator is illustrated under moderate sample sizes. Finally, we apply the new estimator to a well-known real dataset.
On-line monitoring of the metabolic activity of microorganisms involved in intermediate stages of biogas production plays an important role to avoid undesirable “down times” during the biogas production. In order to control this process, an on-chip differential measuring system based on the light-addressable potentiometric sensor (LAPS) principle combined with a 3D-printed multi-chamber structure has been realized. As a test microorganism, Escherichia coli K12 (E. coli K12) were used for cell-based measurements. Multi-chamber structures were developed to determine the metabolic activity of E. coli K12 in suspension for a different number of cells, responding to the addition of a constant or variable amount of glucose concentrations, enabling differential and simultaneous measurements.
Breast cancer resistance protein (BCRP) is expressed in various tissues, such as the gut, liver, kidney and blood brain barrier (BBB), where it mediates the unidirectional transport of substrates to the apical/luminal side of polarized cells. Thereby BCRP acts as an efflux pump, mediating the elimination or restricting the entry of endogenous compounds or xenobiotics into tissues and it plays important roles in drug disposition, efficacy and safety. Bcrp knockout mice (Bcrp−/−) have been used widely to study the role of this transporter in limiting intestinal absorption and brain penetration of substrate compounds. Here we describe the first generation and characterization of a mouse line humanized for BCRP (hBCRP), in which the mouse coding sequence from the start to stop codon was replaced with the corresponding human genomic region, such that the human transporter is expressed under control of the murine Bcrp promoter. We demonstrate robust human and loss of mouse BCRP/Bcrp mRNA and protein expression in the hBCRP mice and the absence of major compensatory changes in the expression of other genes involved in drug metabolism and disposition. Pharmacokinetic and brain distribution studies with several BCRP probe substrates confirmed the functional activity of the human transporter in these mice. Furthermore, we provide practical examples for the use of hBCRP mice to study drug-drug interactions (DDIs). The hBCRP mouse is a promising model to study the in vivo role of human BCRP in limiting absorption and BBB penetration of substrate compounds and to investigate clinically relevant DDIs involving BCRP.
Evaluation of fragility curves for a three-storey-reinforced-concrete mock-up of SMART 2013 project
(2016)
Zur Unterstützung des Transformationsbedarfs von Telekommunikationsunternehmen sind die Referenzmodelle des TM Forums in der Praxis weltweit anerkannt. Dabei findet jedoch meist eine losgelöste Nutzung für spezifische Einzelthemen statt. Daher führt dieser Artikel die bestehenden Inhalte in einer industriespezifischen, übergreifenden Referenzarchitektur zusammen. Der Fokus liegt auf den Ebenen Aufbauorganisation, Prozesse, Applikationen und Daten. Darüber hinaus werden inhaltliche Architekturdomänen zur Strukturierung angeboten. Die Referenzarchitektur ist hierarchisch aufgebaut und wird hier beispielhaft für ausgewählte, aggregierte Inhalte beschrieben. Als erste Evaluation wird die Anwendung der Referenzarchitektur in drei Praxisprojekten erläutert.
Ein Drittel der Mitarbeiter der Saint-Gobain Glass Deutschland
GmbH hat drei Jahre lang regelmäßig seinen Rücken trainiert.
Mit Erfolg, wie eine abschließende Evaluation in Zusammenarbeit
mit der FH Aachen zeigt. Die Fehltage der Trainingsteilnehmer
sind enorm zurückgegangen, während die untrainierten Kollegen
weiterhin unter Rückenbeschwerden leiden.
Objective
This study assesses and quantifies impairment of postoperative magnetic resonance imaging (MRI) at 7 Tesla (T) after implantation of titanium cranial fixation plates (CFPs) for neurosurgical bone flap fixation.
Materials and methods
The study group comprised five patients who were intra-individually examined with 3 and 7 T MRI preoperatively and postoperatively (within 72 h/3 months) after implantation of CFPs. Acquired sequences included T₁-weighted magnetization-prepared rapid-acquisition gradient-echo (MPRAGE), T₂-weighted turbo-spin-echo (TSE) imaging, and susceptibility-weighted imaging (SWI). Two experienced neurosurgeons and a neuroradiologist rated image quality and the presence of artifacts in consensus reading.
Results
Minor artifacts occurred around the CFPs in MPRAGE and T2 TSE at both field strengths, with no significant differences between 3 and 7 T. In SWI, artifacts were accentuated in the early postoperative scans at both field strengths due to intracranial air and hemorrhagic remnants. After resorption, the brain tissue directly adjacent to skull bone could still be assessed. Image quality after 3 months was equal to the preoperative examinations at 3 and 7 T.
Conclusion
Image quality after CFP implantation was not significantly impaired in 7 T MRI, and artifacts were comparable to those in 3 T MRI.
Die stoffliche Nutzung von Lignin aus Bioraffinerien ist ein wichtiger Bestandteil für den Wertschöpfungsprozess von nachwachsenden, pflanzlichen Rohstoffen. Lignin zählt zu den wenigen erneuerbaren Quellen für phenolische Bestandteile, wird aber derzeit meist nur thermisch verwertet. Ziel dieses Forschungsvorhabens ist die Funktionalisierung von Lignin zur Verbesserung der Adhäsionseigenschaften. Als funktionelle Gruppe wird die aromatische Aminosäure L-DOPA verwendet, die charakteristisch für die Adhäsionskraft von Muscheln ist. Lignin ist ein geeignetes Stützgerüst, da es ein Polymer ist, das durch enzymkatalysierte Polymerisation gebildet wird. Essenziell für die Entwicklung ist ein besseres Verständnis über die Bildung von Lignin-Polymeren und deren verschiedene Eigenschaften. Um die Einflussfaktoren auf Kettenlänge und Polymerisationseffizienz zu untersuchen, werden zurzeit sowohl Ligninmodellkomponenten (LMK) als auch gelöstes Organosolv-Lignin verwendet. Laufende Untersuchungen werden zeigen, ob sich die enzymatische Polymerisationsreaktion auf ein gelöstes Ligninpolymer aus einem Organosolv-Aufschluss übertragen lässt.
A New Class of Biosensors Based on Tobacco Mosaic Virus and Coat Proteins as Enzyme Nanocarrier
(2016)
The behaviour of infilled reinforced concrete frames under horizontal load has been widely investigated, both experimentally and numerically. Since experimental tests represent large investments, numerical simulations offer an efficient approach for a more comprehensive analysis. When RC frames with masonry infill walls are subjected to horizontal loading, their behaviour is highly non-linear after a certain limit, which makes their analysis quite difficult. The non-linear behaviour results from the complex inelastic material properties of the concrete, infill wall and conditions at the wall-frame interface. In order to investigate this non-linear behaviour in detail, a finite element model using a micro modelling approach is developed, which is able to predict the complex non-linear behaviour resulting from the different materials and their interaction. Concrete and bricks are represented by a non-linear material model, while each reinforcement bar is represented as an individual part installed in the concrete part and behaving elasto-plastically. Each brick is modelled individually and connected taking into account the non-linearity of a brick mortar interface. The same approach is followed using two finite element software packages and the results are compared with the experimental results. The numerical models show a good agreement with the experiments in predicting the overall behaviour, but also very good matching for strength capacity and drift. The results emphasize the quality and the valuable contribution of the numerical models for use in parametric studies, which are needed for the derivation of design recommendations for infilled frame structures.
Application of the optical flow method to velocity determination in hydraulic structure models
(2016)
Optical flow estimation is known from Computer Vision where it is used to determine obstacle movements through a sequence of images following an assumption of brightness conservation. This paper presents the first study on application of the optical flow method to aerated stepped spillway flows. For this purpose, the flow is captured with a high-speed camera and illuminated with a synchronized LED light source. The flow velocities, obtained using a basic Horn–Schunck method for estimation of the optical flow coupled with an image pyramid multi-resolution approach for image filtering, compare well with data from intrusive conductivity probe measurements. Application of the Horn–Schunck method yields densely populated flow field data sets with velocity information for every pixel. It is found that the image pyramid approach has the most significant effect on the accuracy compared to other image processing techniques. However, the final results show some dependency on the pixel intensity distribution, with better accuracy found for grey values between 100 and 150.
Abstractauthoren Graphene oxide (GO) nanoparticles were incorporated in temperature-sensitive Poly(N-isopropylacrylamide) (PNIPAAm) hydrogels. The nanoparticles increase the light absorption and convert light energy into heat efficiently. Thus, the hydrogels with GO can be stimulated spatially resolved by illumination as it was demonstrated by IR thermography. The temporal progression of the temperature maximum was detected for different concentrations of GO within the polymer network. Furthermore, the compatibility of PNIPAAm hydrogels with GO and cell cultures was investigated. For this purpose, culture medium was incubated with hydrogels containing GO and the viability and morphology of chinese hamster ovary (CHO) cells was examined after several days of culturing in presence of this medium.
Unser Zuhause wird zunehmend intelligenter. Smart Homes bieten uns die Steuerung von Haus- oder Unterhaltungstechnik bequem vom Smartphone aus. Junge Familien nutzen die Technologie, um mittels vernetzten Babymonitorsystemen ihren Nachwuchs von überall aus im Blick zu haben. Davon auszugehen, dass solche Systeme mit einem Fokus auf Sicherheit entwickelt wurden, um die sehr persönlichen Daten zu schützen, ist jedoch ein Trugschluss. Die Untersuchung eines handelsüblichen und keineswegs billigen Systems zeigt, dass die Geräte sehr einfach kompromittiert und missbraucht werden können.
Der Beitrag fokussiert die Frage nach dem Stand des durch die Bologna-Reform angestoßenen Kulturwandels im Hinblick auf Kompetenzorientierung am Beispiel der Technischen Universität Hamburg (TUHH). An der TUHH wird bereits seit einigen Jahren daran gearbeitet, die Lehre grundlegend neu auszurichten. Hierfür setzt das hochschuldidaktische "Zentrum für Lehre und Lernen" (ZLL) verschiedene Maßnahmen ein, wie z.B. eine finanzielle und didaktische Unterstützung von Lehrenden bei der Umstellung ihrer Veranstaltungen, Weiterqualifizierungsangebote und Informationsmaterial. Die Maßnahmen ebenso wie die innovierten Veranstaltungen werden von Lehrenden und Studierenden gut evaluiert. Nach dem Ansatz des Constructive Alignments lässt sich jedoch davon ausgehen, dass der Bereich der Prüfungen für eine Einschätzung des Status Quo der Kompetenzorientierung besonders relevant ist. Dieser wird deshalb anhand der beiden Kriterien Prüfungsformate und Schwierigkeitsstufen von Prüfungsaufgaben näher beleuchtet, die eng mit der Kompetenzorientierung zusammen hängen. Ergebnisse hierzu aus einer universitätsweiten Datenbank zur Studienorganisation sowie aus einer Online-Umfrage unter Studierenden weisen darauf hin, dass das Prüfungsformat "Klausur" nach wie vor am stärksten verbreitet ist; zugleich sind die Studierenden nach einer Selbsteinschätzung in Prüfungen vorrangig mit Aufgaben auf den Taxonomieniveaus "Wiedergeben" und "Anwenden" konfrontiert. Dies lässt sich als Hinweis darauf interpretieren, dass es im Hinblick auf eine Kompetenzorientierung in den Prüfungen noch weiteren Veränderungsbedarf gibt.
The stimulation and dominance of potentially harmful phytoplankton taxa at a given locale and time are determined by local environmental conditions as well as by transport to or from neighboring regions. The present study investigated the occurrence of common harmful algal bloom (HAB) taxa within the Southern California Bight, using cross-correlation functions to determine potential dependencies between HAB taxa and environmental factors, and potential links to algal transport via local hydrography and currents. A simulation study, in which Lagrangian particles were released, was used to assess travel times due to advection by prevailing ocean currents in the bight. Our results indicate that transport of some taxa may be an important mechanism for the expansion of their distributions into other regions, which was supported by mean travel times derived from our simulation study and other literature on ocean currents in the Southern California Bight. In other cases, however, phytoplankton dynamics were rather linked to local environmental conditions, including coastal upwelling events. Overall, our study shows that complex current patterns in the Southern California Bight may contribute significantly to the formation and expansion of HABs in addition to local environmental factors determining the spatiotemporal dynamics of phytoplankton blooms.
The structure of the female pelvic floor (PF) is an inter-related system of bony pelvis,muscles, pelvic organs, fascias, ligaments, and nerves with multiple functions. Mechanically, thepelvic organ support system are of two types: (I) supporting system of the levator ani (LA) muscle,and (II) the suspension system of the endopelvic fascia condensation [1], [2]. Significantdenervation injury to the pelvic musculature, depolimerization of the collagen fibrils of the softvaginal hammock, cervical ring and ligaments during pregnancy and vaginal delivery weakens thenormal functions of the pelvic floor. Pelvic organ prolapse, incontinence, sexual dysfunction aresome of the dysfunctions which increases progressively with age and menopause due toweakened support system according to the Integral theory [3]. An improved 3D finite elementmodel of the female pelvic floor as shown in Fig. 1 is constructed that: (I) considers the realisticsupport of the organs to the pelvic side walls, (II) employs the improvement of our previous FEmodel [4], [5] along with the patient based geometries, (III) incorporates the realistic anatomy andboundary conditions of the endopelvic (pubocervical and rectovaginal) fascia, and (IV) considersvarying stiffness of the endopelvic fascia in the craniocaudal direction [3]. Several computationsare carried out on the presented computational model with healthy and damaged supportingtissues, and comparisons are made to understand the physiopathology of the female PF disorders.
Divided government is often thought of as causing legislative deadlock. I investigate the link between divided government and economic reforms using a novel data set on welfare reforms in US states between 1978 and 2010. Panel data regressions show that, under divided government, a US state is around 25% more likely to adopt a welfare reform than under unified government. Several robustness checks confirm this counter-intuitive finding. Case study evidence suggests an explanation based on policy competition between governor, senate, and house.
To better understand what kinds of sports and exercise could be beneficial for the intervertebral disc (IVD), we performed a review to synthesise the literature on IVD adaptation with loading and exercise. The state of the literature did not permit a systematic review; therefore, we performed a narrative review. The majority of the available data come from cell or whole-disc loading models and animal exercise models. However, some studies have examined the impact of specific sports on IVD degeneration in humans and acute exercise on disc size. Based on the data available in the literature, loading types that are likely beneficial to the IVD are dynamic, axial, at slow to moderate movement speeds, and of a magnitude experienced in walking and jogging. Static loading, torsional loading, flexion with compression, rapid loading, high-impact loading and explosive tasks are likely detrimental for the IVD. Reduced physical activity and disuse appear to be detrimental for the IVD. We also consider the impact of genetics and the likelihood of a ‘critical period’ for the effect of exercise in IVD development. The current review summarises the literature to increase awareness amongst exercise, rehabilitation and ergonomic professionals regarding IVD health and provides recommendations on future directions in research.
Malware auf Smartphones ist ein Problem, dem auch Strafverfolgungsbehörden immer häufiger gegenüberstehen.
Insbesondere Telefone, bei denen potentiell schadhafte Apps zu einem finanziellen Schaden
geführt haben, finden sich auf den Schreibtischen der Polizei wieder. Dabei müssen die Ermittler möglichst
schnell und gezielt erkennen können, ob eine App tatsächlich schadhaft manipuliert wurde, was
manipuliert wurde und mit wem die App kommuniziert. Klassische Malware-Erkennungsverfahren helfen
zwar bei der generellen Erkennung schadhafter Software, sind aber für die polizeiliche Praxis nicht
geeignet. Dieses Paper stellt ein Programm vor, welches gerade die forensischen Fragestellungen berücksichtigt
und so für den Einsatz in der Strafverfolgung in Frage kommt.
Given the strong increase in regulatory requirements for business processes the management of business process compliance becomes a more and more regarded field in IS research. Several methods have been developed to support compliance checking of conceptual models. However, their focus on distinct modeling languages and mostly linear (i.e., predecessor-successor related) compliance rules may hinder widespread adoption and application in practice. Furthermore, hardly any of them has been evaluated in a real-world setting. We address this issue by applying a generic pattern matching approach for conceptual models to business process compliance checking in the financial sector. It consists of a model query language, a search algorithm and a corresponding modelling tool prototype. It is (1) applicable for all graph-based conceptual modeling languages and (2) for different kinds of compliance rules. Furthermore, based on an applicability check, we (3) evaluate the approach in a financial industry project setting against its relevance for decision support of audit and compliance management tasks.
We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.
A comparative performance analysis of the CFD platforms OpenFOAM and FLOW-3D is presented, focusing on a 3D swirling turbulent flow: a steady hydraulic jump at low Reynolds number. Turbulence is treated using RANS approach RNG k-ε. A Volume Of Fluid (VOF) method is used to track the air–water interface, consequently aeration is modeled using an Eulerian–Eulerian approach. Structured meshes of cubic elements are used to discretize the channel geometry. The numerical model accuracy is assessed comparing representative hydraulic jump variables (sequent depth ratio, roller length, mean velocity profiles, velocity decay or free surface profile) to experimental data. The model results are also compared to previous studies to broaden the result validation. Both codes reproduced the phenomenon under study concurring with experimental data, although special care must be taken when swirling flows occur. Both models can be used to reproduce the hydraulic performance of energy dissipation structures at low Reynolds numbers.
Im Mai 2012 fand in Hamburg erstmals das „Junge Forum Hochschul- und Mediendidaktik“ statt, im Juni 2013 folgte in Potsdam die zweite Auflage als „Junges Forum Medien und Hochschulentwicklung“. 2014 wurde das dritte „Forum“ in Dresden und 2015 das vierte in Düsseldorf ausgerichtet. Das fünfte Forum wird 2016 an der Technischen Universität Darmstadt stattfinden. Initiiert und organisiert wird die Veranstaltung stets von jungen Praktikerinnen und Praktikern sowie Forscherinnen und Forschern mit dem Ziel, dem ‚Nachwuchs‘ in diesem Bereich ein Austauschforum zu geben. Der vorliegende Artikel stellt die konzeptionellen Überlegungen vor, die hinter diesen Treffen stehen. Er zeigt im Rückgriff auf Netzwerktheorie und aktuelle Diskussionen um Professionalisierung und Third Space, wieso für dieses Format ein aktueller Bedarf besteht, und begründet dann im Rückgriff auf didaktische Konzepte auch die methodische Gestaltung der Veranstaltungen. Unsere These: Das kooperative Lernen in Netzwerken ist ein wichtiger Baustein für die Professionalisierung des hochschul- und mediendidaktischen Nachwuchses.