@misc{WandreyBiselliSchroederetal.1999, author = {Wandrey, Christian and Biselli, Manfred and Schr{\"o}der, Bernd and Schmoll, Hans-Joachim}, title = {Culturing cells on macroporous glass carriers coated with gelatin, extracellular matrix protein and stromal cells}, pages = {1 -- 12}, year = {1999}, language = {en} } @article{KromeHoeftSander2019, author = {Krome, Cornelia and H{\"o}ft, Jan and Sander, Volker}, title = {Clustering time series applied to energy markets}, series = {Energy Informatics}, volume = {2}, journal = {Energy Informatics}, number = {Article numer 17}, publisher = {Springer}, address = {Berlin}, issn = {2520-8942}, doi = {10.1186/s42162-019-0076-0}, pages = {1 -- 20}, year = {2019}, language = {en} } @phdthesis{Duong2015, author = {Duong, Minh Tuan}, title = {Hyperelastic modeling and soft-tissue growth integrated with the smoothed finite element method - SFEM}, publisher = {RWTH Aachen University}, pages = {174 S.}, year = {2015}, language = {en} } @phdthesis{Pham2011, author = {Pham, Phu Tinh}, title = {Upper bound limit and shakedown analysis of elastic-plastic bounded linearly kinematic hardening structures}, publisher = {RWTH Aachen University}, address = {Aachen}, pages = {140 S.}, year = {2011}, language = {en} } @article{QuittmannAbelAlbrachtetal.2020, author = {Quittmann, Oliver J. and Abel, Thomas and Albracht, Kirsten and Meskemper, Joshua and Foitschik, Tina and Str{\"u}der, Heiko K.}, title = {Biomechanics of handcycling propulsion in a 30-min continuous load test at lactate threshold: Kinetics, kinematics, and muscular activity in able-bodied participants}, series = {European Journal of Applied Physiology}, journal = {European Journal of Applied Physiology}, number = {120}, publisher = {Springer}, address = {Heidelberg}, issn = {1439-6327}, doi = {10.1007/s00421-020-04373-x}, pages = {1403 -- 1415}, year = {2020}, abstract = {Purpose This study aims to investigate the biomechanics of handcycling during a continuous load trial (CLT) to assess the mechanisms underlying fatigue in upper body exercise. Methods Twelve able-bodied triathletes performed a 30-min CLT at a power output corresponding to lactate threshold in a racing recumbent handcycle mounted on a stationary ergometer. During the CLT, ratings of perceived exertion (RPE), tangential crank kinetics, 3D joint kinematics, and muscular activity of ten muscles of the upper extremity and trunk were examined using motion capturing and surface electromyography. Results During the CLT, spontaneously chosen cadence and RPE increased, whereas crank torque decreased. Rotational work was higher during the pull phase. Peripheral RPE was higher compared to central RPE. Joint range of motion decreased for elbow-flexion and radial-duction. Integrated EMG (iEMG) increased in the forearm flexors, forearm extensors, and M. deltoideus (Pars spinalis). An earlier onset of activation was found for M. deltoideus (Pars clavicularis), M. pectoralis major, M. rectus abdominis, M. biceps brachii, and the forearm flexors. Conclusion Fatigue-related alterations seem to apply analogously in handcycling and cycling. The most distal muscles are responsible for force transmission on the cranks and might thus suffer most from neuromuscular fatigue. The findings indicate that peripheral fatigue (at similar lactate values) is higher in handcycling compared to leg cycling, at least for inexperienced participants. An increase in cadence might delay peripheral fatigue by a reduced vascular occlusion. We assume that the gap between peripheral and central fatigue can be reduced by sport-specific endurance training.}, language = {en} } @inproceedings{PohleFroehlichDalitzRichteretal.2020, author = {Pohle-Fr{\"o}hlich, Regina and Dalitz, Christoph and Richter, Charlotte and Hahnen, Tobias and St{\"a}udle, Benjamin and Albracht, Kirsten}, title = {Estimation of muscle fascicle orientation in ultrasonic images}, series = {Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 5}, booktitle = {Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 5}, publisher = {SciTePress}, address = {Set{\´u}bal, Portugal}, isbn = {978-989-758-402-2}, doi = {10.5220/0008933900790086}, pages = {79 -- 86}, year = {2020}, abstract = {We compare four different algorithms for automatically estimating the muscle fascicle angle from ultrasonic images: the vesselness filter, the Radon transform, the projection profile method and the gray level cooccurence matrix (GLCM). The algorithm results are compared to ground truth data generated by three different experts on 425 image frames from two videos recorded during different types of motion. The best agreement with the ground truth data was achieved by a combination of pre-processing with a vesselness filter and measuring the angle with the projection profile method. The robustness of the estimation is increased by applying the algorithms to subregions with high gradients and performing a LOESS fit through these estimates.}, language = {en} } @article{DantismRoehlenDahmenetal.2020, author = {Dantism, Shahriar and R{\"o}hlen, Desiree and Dahmen, Markus and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {LAPS-based monitoring of metabolic responses of bacterial cultures in a paper fermentation broth}, series = {Sensors and Actuators B: Chemical}, volume = {320}, journal = {Sensors and Actuators B: Chemical}, number = {Art. 128232}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2020.128232}, year = {2020}, abstract = {As an alternative renewable energy source, methane production in biogas plants is gaining more and more attention. Biomass in a bioreactor contains different types of microorganisms, which should be considered in terms of process-stability control. Metabolically inactive microorganisms within the fermentation process can lead to undesirable, time-consuming and cost-intensive interventions. Hence, monitoring of the cellular metabolism of bacterial populations in a fermentation broth is crucial to improve the biogas production, operation efficiency, and sustainability. In this work, the extracellular acidification of bacteria in a paper-fermentation broth is monitored after glucose uptake, utilizing a differential light-addressable potentiometric sensor (LAPS) system. The LAPS system is loaded with three different model microorganisms (Escherichia coli, Corynebacterium glutamicum, and Lactobacillus brevis) and the effect of the fermentation broth at different process stages on the metabolism of these bacteria is studied. In this way, different signal patterns related to the metabolic response of microorganisms can be identified. By means of calibration curves after glucose uptake, the overall extracellular acidification of bacterial populations within the fermentation process can be evaluated.}, language = {en} } @article{RoethSlabuKessleretal.2019, author = {Roeth, A.A. and Slabu, I. and Kessler, A. and Engelmann, Ulrich M.}, title = {Local treatment of pancreatic cancer with magnetic nanoparticles}, series = {HPB}, volume = {21}, journal = {HPB}, number = {Supplement 3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1365-182X}, doi = {10.1016/j.hpb.2019.10.959}, pages = {S868 -- S869}, year = {2019}, language = {en} } @article{WeldenSchoeningWagneretal.2020, author = {Welden, Rene and Sch{\"o}ning, Michael Josef and Wagner, Patrick H. and Wagner, Torsten}, title = {Light-Addressable Electrodes for Dynamic and Flexible Addressing of Biological Systems and Electrochemical Reactions}, series = {Sensors}, volume = {20}, journal = {Sensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s20061680}, pages = {Artikel 1680}, year = {2020}, abstract = {In this review article, we are going to present an overview on possible applications of light-addressable electrodes (LAE) as actuator/manipulation devices besides classical electrode structures. For LAEs, the electrode material consists of a semiconductor. Illumination with a light source with the appropiate wavelength leads to the generation of electron-hole pairs which can be utilized for further photoelectrochemical reaction. Due to recent progress in light-projection technologies, highly dynamic and flexible illumination patterns can be generated, opening new possibilities for light-addressable electrodes. A short introduction on semiconductor-electrolyte interfaces with light stimulation is given together with electrode-design approaches. Towards applications, the stimulation of cells with different electrode materials and fabrication designs is explained, followed by analyte-manipulation strategies and spatially resolved photoelectrochemical deposition of different material types.}, language = {en} } @article{JildehKirchnerOberlaenderetal.2020, author = {Jildeh, Zaid B. and Kirchner, Patrick and Oberl{\"a}nder, Jan and Vahidpour, Farnoosh and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef}, title = {Development of a package-sterilization process for aseptic filling machines: A numerical approach and validation for surface treatment with hydrogen peroxide}, series = {Sensor and Actuators A: Physical}, volume = {303}, journal = {Sensor and Actuators A: Physical}, number = {111691}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0924-4247}, doi = {10.1016/j.sna.2019.111691}, year = {2020}, abstract = {Within the present work a sterilization process by a heated gas mixture that contains hydrogen peroxide (H₂O₂) is validated by experiments and numerical modeling techniques. The operational parameters that affect the sterilization efficacy are described alongside the two modes of sterilization: gaseous and condensed H₂O₂. Measurements with a previously developed H₂O₂ gas sensor are carried out to validate the applied H₂O₂ gas concentration during sterilization. We performed microbiological tests at different H₂O₂ gas concentrations by applying an end-point method to carrier strips, which contain different inoculation loads of Geobacillus stearothermophilus spores. The analysis of the sterilization process of a pharmaceutical glass vial is performed by numerical modeling. The numerical model combines heat- and advection-diffusion mass transfer with vapor-pressure equations to predict the location of condensate formation and the concentration of H₂O₂ at the packaging surfaces by changing the gas temperature. For a sterilization process of 0.7 s, a H₂O₂ gas concentration above 4\% v/v is required to reach a log-count reduction above six. The numerical results showed the location of H₂O₂ condensate formation, which decreases with increasing sterilant-gas temperature. The model can be transferred to different gas nozzle- and packaging geometries to assure the absence of H₂O₂ residues.}, language = {en} } @inproceedings{HingleyDikta2019, author = {Hingley, Peter and Dikta, Gerhard}, title = {Finding a well performing box-jenkins forecasting model for annualised patent filings counts}, series = {International Symposium on Forecasting, Thessaloniki, Greece, June 2019}, booktitle = {International Symposium on Forecasting, Thessaloniki, Greece, June 2019}, pages = {24 Folien}, year = {2019}, language = {en} } @article{AttarMerkKotliaretal.2019, author = {Attar, Mandana Hossein Zadeh and Merk, Hans F. and Kotliar, Konstantin and Wurpts, Gerda and R{\"o}seler, Stefani and Moll-Slodowy, Silke and Plange, Johann and Baron, Jens Malte and Balakirski, Galina}, title = {The CD63 basophil activation test as a diagnostic tool for assessing autoimmunity in patients with chronic spontaneous urticaria}, series = {European Journal of Dermatology}, volume = {29}, journal = {European Journal of Dermatology}, number = {6}, doi = {10.1684/ejd.2019.3680}, pages = {614 -- 618}, year = {2019}, language = {en} } @article{MennickenPeterKaulenetal.2020, author = {Mennicken, Max and Peter, Sophia K. and Kaulen, Corinna and Simon, Ulrich and Karth{\"a}user, Silvia}, title = {Transport through Redox-Active Ru-Terpyridine Complexes Integrated in Single Nanoparticle Devices}, series = {The Journal of Physical Chemistry C}, volume = {124}, journal = {The Journal of Physical Chemistry C}, number = {8}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {1932-7455}, doi = {10.1021/acs.jpcc.9b11716}, pages = {4881 -- 4889}, year = {2020}, abstract = {Transition metal complexes are electrofunctional molecules due to their high conductivity and their intrinsic switching ability involving a metal-to-ligand charge transfer. Here, a method is presented to contact reliably a few to single redox-active Ru-terpyridine complexes in a CMOS compatible nanodevice and preserve their electrical functionality. Using hybrid materials from 14 nm gold nanoparticles (AuNP) and bis-{4′-[4-(mercaptophenyl)-2,2′:6′,2″-terpyridine]}-ruthenium(II) complexes a device size of 30² nm² inclusive nanoelectrodes is achieved. Moreover, this method bears the opportunity for further downscaling. The Ru-complex AuNP devices show symmetric and asymmetric current versus voltage curves with a hysteretic characteristic in two well separated conductance ranges. By theoretical approximations based on the single-channel Landauer model, the charge transport through the formed double-barrier tunnel junction is thoroughly analyzed and its sensibility to the molecule/metal contact is revealed. It can be verified that tunneling transport through the HOMO is the main transport mechanism while decoherent hopping transport is present to a minor extent.}, language = {en} } @article{PilasSelmerKeusgenetal.2019, author = {Pilas, Johanna and Selmer, Thorsten and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Screen-printed carbon electrodes modified with graphene oxide for the design of a reagent-free NAD+-dependent biosensor array}, series = {Analytical Chemistry}, volume = {91}, journal = {Analytical Chemistry}, number = {23}, publisher = {ACS Publications}, address = {Washington}, doi = {10.1021/acs.analchem.9b04481}, pages = {15293 -- 15299}, year = {2019}, language = {en} } @article{GrundlachBaumannEngelmann2021, author = {Grundlach, Michael and Baumann, Martin and Engelmann, Ulrich M.}, title = {How Multimodal Examinations Can Increase Sustainable Student Gain by Aligning Teaching and Assessment}, series = {Current Directions in Biomedical Engineering}, volume = {7}, journal = {Current Directions in Biomedical Engineering}, number = {7/2}, editor = {D{\"o}ssel, Olaf}, publisher = {De Gruyter}, address = {Berlin}, isbn = {2364-5504}, doi = {10.1515/cdbme-2021-2019}, pages = {73 -- 76}, year = {2021}, abstract = {Modern industry and multi-discipline projects require highly trained individuals with resilient science and engineering back-grounds. Graduates must be able to agilely apply excellent theoretical knowledge in their subject matter as well as essential practical "hands-on" knowledge of diverse working processes to solve complex problems. To meet these demands, university education follows the concept of Constructive Alignment and thus increasingly adopts the teaching of necessary practical skills to the actual industry requirements and assessment routines. However, a systematic approach to coherently align these three central teaching demands is strangely absent from current university curricula. We demonstrate the feasibility of implementing practical assessments in a regular theory-based examination, thus defining the term "blended assessment". We assessed a course for natural science and engineering students pursuing a career in biomedical engineering, and evaluated the benefit of blended assessment exams for students and lecturers. Our controlled study assessed the physiological background of electrocardiograms (ECGs), the practical measurement of ECG curves, and their interpretation of basic pathologic alterations. To study on long time effects, students have been assessed on the topic twice with a time lag of 6 months. Our findings suggest a significant improvement in student gain with respect to practical skills and theoretical knowledge. The results of the reassessments support these outcomes. From the lecturers' point of view, blended assessment complements practical training courses while keeping organizational effort manageable. We consider blended assessment a viable tool for providing an improved student gain, industry-ready education format that should be evaluated and established further to prepare university graduates optimally for their future careers.}, language = {en} } @article{PoettgenEdererAltherretal.2015, author = {P{\"o}ttgen, Philipp and Ederer, Thorsten and Altherr, Lena and Pelz, Peter F.}, title = {Developing a control strategy for booster stations under uncertain load}, series = {Applied Mechanics and Materials}, volume = {807}, journal = {Applied Mechanics and Materials}, number = {807}, publisher = {Trans Tech Publications}, address = {B{\"a}ch}, isbn = {1662-7482}, doi = {10.4028/www.scientific.net/AMM.807.241}, pages = {241 -- 246}, year = {2015}, abstract = {Booster stations can fulfill a varying pressure demand with high energy-efficiency, because individual pumps can be deactivated at smaller loads. Although this is a seemingly simple approach, it is not easy to decide precisely when to activate or deactivate pumps. Contemporary activation controls derive the switching points from the current volume flow through the system. However, it is not measured directly for various reasons. Instead, the controller estimates the flow based on other system properties. This causes further uncertainty for the switching decision. In this paper, we present a method to find a robust, yet energy-efficient activation strategy.}, language = {en} } @inproceedings{BuesgenKloeserKohletal.2022, author = {B{\"u}sgen, Andr{\´e} and Kl{\"o}ser, Lars and Kohl, Philipp and Schmidts, Oliver and Kraft, Bodo and Z{\"u}ndorf, Albert}, title = {Exploratory analysis of chat-based black market profiles with natural language processing}, series = {Proceedings of the 11th International Conference on Data Science, Technology and Applications}, booktitle = {Proceedings of the 11th International Conference on Data Science, Technology and Applications}, isbn = {978-989-758-583-8}, issn = {2184-285X}, doi = {10.5220/0011271400003269}, pages = {83 -- 94}, year = {2022}, abstract = {Messenger apps like WhatsApp or Telegram are an integral part of daily communication. Besides the various positive effects, those services extend the operating range of criminals. Open trading groups with many thousand participants emerged on Telegram. Law enforcement agencies monitor suspicious users in such chat rooms. This research shows that text analysis, based on natural language processing, facilitates this through a meaningful domain overview and detailed investigations. We crawled a corpus from such self-proclaimed black markets and annotated five attribute types products, money, payment methods, user names, and locations. Based on each message a user sends, we extract and group these attributes to build profiles. Then, we build features to cluster the profiles. Pretrained word vectors yield better unsupervised clustering results than current state-of-the-art transformer models. The result is a semantically meaningful high-level overview of the user landscape of black market chatrooms. Additionally, the extracted structured information serves as a foundation for further data exploration, for example, the most active users or preferred payment methods.}, language = {en} } @article{MandekarHollandThielenetal.2022, author = {Mandekar, Swati and Holland, Abigail and Thielen, Moritz and Behbahani, Mehdi and Melnykowycz, Mark}, title = {Advancing towards Ubiquitous EEG, Correlation of In-Ear EEG with Forehead EEG}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22041568}, pages = {1 -- 19}, year = {2022}, abstract = {Wearable EEG has gained popularity in recent years driven by promising uses outside of clinics and research. The ubiquitous application of continuous EEG requires unobtrusive form-factors that are easily acceptable by the end-users. In this progression, wearable EEG systems have been moving from full scalp to forehead and recently to the ear. The aim of this study is to demonstrate that emerging ear-EEG provides similar impedance and signal properties as established forehead EEG. EEG data using eyes-open and closed alpha paradigm were acquired from ten healthy subjects using generic earpieces fitted with three custom-made electrodes and a forehead electrode (at Fpx) after impedance analysis. Inter-subject variability in in-ear electrode impedance ranged from 20 kΩ to 25 kΩ at 10 Hz. Signal quality was comparable with an SNR of 6 for in-ear and 8 for forehead electrodes. Alpha attenuation was significant during the eyes-open condition in all in-ear electrodes, and it followed the structure of power spectral density plots of forehead electrodes, with the Pearson correlation coefficient of 0.92 between in-ear locations ELE (Left Ear Superior) and ERE (Right Ear Superior) and forehead locations, Fp1 and Fp2, respectively. The results indicate that in-ear EEG is an unobtrusive alternative in terms of impedance, signal properties and information content to established forehead EEG.}, language = {en} } @article{PhilippEfthimiouPaganoetal.2022, author = {Philipp, Mohr and Efthimiou, Nikos and Pagano, Fiammetta and Kratochwil, Nicolaus and Pizzichemi, Marco and Tsoumpas, Charalampos and Auffray, Etiennette and Ziemons, Karl}, title = {Image reconstruction analysis for positron emission tomography with heterostructured scintillators}, series = {IEEE Transactions on Radiation and Plasma Medical Sciences}, volume = {7}, journal = {IEEE Transactions on Radiation and Plasma Medical Sciences}, number = {1}, publisher = {IEEE}, address = {New York, NY}, issn = {2469-7311}, doi = {10.1109/TRPMS.2022.3208615}, pages = {41 -- 51}, year = {2022}, abstract = {The concept of structure engineering has been proposed for exploring the next generation of radiation detectors with improved performance. A TOF-PET geometry with heterostructured scintillators with a pixel size of 3.0×3.1×15 mm3 was simulated using Monte Carlo. The heterostructures consisted of alternating layers of BGO as a dense material with high stopping power and plastic (EJ232) as a fast light emitter. The detector time resolution was calculated as a function of the deposited and shared energy in both materials on an event-by-event basis. While sensitivity was reduced to 32\% for 100 μm thick plastic layers and 52\% for 50 μm, the CTR distribution improved to 204±49 ps and 220±41 ps respectively, compared to 276 ps that we considered for bulk BGO. The complex distribution of timing resolutions was accounted for in the reconstruction. We divided the events into three groups based on their CTR and modeled them with different Gaussian TOF kernels. On a NEMA IQ phantom, the heterostructures had better contrast recovery in early iterations. On the other hand, BGO achieved a better contrast to noise ratio (CNR) after the 15th iteration due to the higher sensitivity. The developed simulation and reconstruction methods constitute new tools for evaluating different detector designs with complex time responses.}, language = {en} } @article{BaringhausGaigall2022, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {A goodness-of-fit test for the compound Poisson exponential model}, series = {Journal of Multivariate Analysis}, volume = {195}, journal = {Journal of Multivariate Analysis}, number = {Article 105154}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2022.105154}, year = {2022}, abstract = {On the basis of bivariate data, assumed to be observations of independent copies of a random vector (S,N), we consider testing the hypothesis that the distribution of (S,N) belongs to the parametric class of distributions that arise with the compound Poisson exponential model. Typically, this model is used in stochastic hydrology, with N as the number of raindays, and S as total rainfall amount during a certain time period, or in actuarial science, with N as the number of losses, and S as total loss expenditure during a certain time period. The compound Poisson exponential model is characterized in the way that a specific transform associated with the distribution of (S,N) satisfies a certain differential equation. Mimicking the function part of this equation by substituting the empirical counterparts of the transform we obtain an expression the weighted integral of the square of which is used as test statistic. We deal with two variants of the latter, one of which being invariant under scale transformations of the S-part by fixed positive constants. Critical values are obtained by using a parametric bootstrap procedure. The asymptotic behavior of the tests is discussed. A simulation study demonstrates the performance of the tests in the finite sample case. The procedure is applied to rainfall data and to an actuarial dataset. A multivariate extension is also discussed.}, language = {en} }