TY - JOUR A1 - Lagemaat, Miriam W. A1 - Breukels, Vincent A1 - Vos, Eline K. A1 - B., Adam A1 - Uden, Mark J. van A1 - Orzada, Stephan A1 - Bitz, Andreas A1 - Maas, Marnix C. A1 - Scheenen, Tom W. J. T1 - ¹H MR spectroscopic imaging of the prostate at 7T using spectral-spatial pulses JF - Magnetic Resonance in Medicine N2 - Purpose To assess the feasibility of prostate ¹H MR spectroscopic imaging (MRSI) using low-power spectral-spatial (SPSP) pulses at 7T, exploiting accurate spectral selection and spatial selectivity simultaneously. Methods A double spin-echo sequence was equipped with SPSP refocusing pulses with a spectral selectivity of 1 ppm. Three-dimensional prostate ¹H-MRSI at 7T was performed with the SPSP-MRSI sequence using an 8-channel transmit array coil and an endorectal receive coil in three patients with prostate cancer and in one healthy subject. No additional water or lipid suppression pulses were used. Results Prostate ¹H-MRSI could be obtained well within specific absorption rate (SAR) limits in a clinically feasible time (10 min). Next to the common citrate signals, the prostate spectra exhibited high spermine signals concealing creatine and sometimes also choline. Residual lipid signals were observed at the edges of the prostate because of limitations in spectral and spatial selectivity. Conclusion It is possible to perform prostate ¹H-MRSI at 7T with a SPSP-MRSI sequence while using separate transmit and receive coils. This low-SAR MRSI concept provides the opportunity to increase spatial resolution of MRSI within reasonable scan times. Y1 - 2016 U6 - http://dx.doi.org/10.1002/mrm.25569 SN - 1522-2594 VL - 75 IS - 3 SP - 933 EP - 945 PB - International Society for Magnetic Resonance in Medicine ER - TY - JOUR A1 - Ferrein, Alexander A1 - Schiffer, Stefan A1 - Booysen, T. A1 - Stopforth, R. T1 - Why it is harder to run RoboCup in South Africa: Experiences from German South African collaborations JF - International Journal of Advanced Robotic Systems N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.1177/1729881416662789 SN - 1729-8806 VL - 13 IS - 5 SP - 1 EP - 13 ER - TY - JOUR A1 - Jablonowski, Nicolai David A1 - Kollmann, Tobias A1 - Nabel, Moritz A1 - Damm, Tatjana A1 - Klose, Holger A1 - Müller, Michael A1 - Bläsing, Marc A1 - Seebold, Sören A1 - Krafft, Simone A1 - Kuperjans, Isabel A1 - Dahmen, Markus A1 - Schurr, Ulrich T1 - Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes JF - GCB [Global Change Biology] Bioenergy N2 - The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha⁻¹, whereas the highest dry matter of 70% to 80% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha⁻¹; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500 °C, associated with a net calorific value of 16.5–17.2 MJ kg⁻¹. All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications. Y1 - 2016 U6 - http://dx.doi.org/10.1111/gcbb.12346 SN - 1757-1707 (online) SN - 1757-1693 (print) N1 - Special Issue: Perennial biomass crops for a resource constrained world VL - 9 IS - 1 SP - 202 EP - 214 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Molinnus, Denise A1 - Sorich, Maren A1 - Bartz, Alexander A1 - Siegert, Petra A1 - Willenberg, Holger S. A1 - Lisdat, Fred A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Towards an adrenaline biosensor based on substrate recycling amplification in combination with an enzyme logic gate JF - Sensors and Actuators B: Chemical N2 - An amperometric biosensor using a substrate recycling principle was realized for the detection of low adrenaline concentrations (1 nM) by measurements in phosphate buffer and Ringer’s solution at pH 6.5 and pH 7.4, respectively. In proof-of-concept experiments, a Boolean logic-gate principle has been applied to develop a digital adrenaline biosensor based on an enzyme AND logic gate. The obtained results demonstrate that the developed digital biosensor is capable for a rapid qualitative determination of the presence/absence of adrenaline in a YES/NO statement. Such digital biosensor could be used in clinical diagnostics for the control of a correct insertion of a catheter in the adrenal veins during adrenal venous-sampling procedure. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.snb.2016.06.064 SN - 0925-4005 VL - 237 SP - 190 EP - 195 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Paulßen, Elisabeth A1 - Lengkeek, Nigel A. A1 - Le, Van So A1 - Pellegrini, Paul A. A1 - Greguric, Ivan A1 - Weiner, Ron T1 - The role of additives in moderating the influence of Fe(III) and Cu(II) on the radiochemical yield of [⁶⁸Ga(DOTATATE)] JF - Applied Radiation and Isotopes N2 - [⁶⁸Ga(DOTATATE)] has demonstrated its clinical usefulness. Both Fe³⁺ and Cu²⁺, potential contaminants in Gallium-68 generator eluent, substantially reduce the radiochemical (RC) yield of [⁶⁸Ga(DOTATATE)] if the metal/ligand ratio of 1:1 is exceeded. A variety of compounds were examined for their potential ability to reduce this effect. Most had no effect on RC yield. However, addition of phosphate diminished the influence of Fe³⁺ by likely forming an insoluble iron salt. Addition of ascorbic acid reduced Cu²⁺ and Fe³⁺ to Cu⁺ and Fe²⁺ respectively, both of which have limited impact on RC yields. At low ligand amounts (5 nmol DOTATATE), the addition of 30 nmol phosphate (0.19 mM) increased the tolerance of Fe3⁺ from 4 nmol to 10 nmol (0.06 mM), while the addition of ascorbic acid allowed high RC yields (>95%) in the presence of 40 nmol Fe³⁺ (0.25 mM) and 100 nmol Cu²⁺ (0.63 mM). The effect of ascorbic acid was highly pH-dependant, and gave optimal results at pH 3. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.apradiso.2015.09.008 SN - 1872-9800 VL - 107 SP - 13 EP - 16 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ferrein, Alexander A1 - Steinbauer, Gerald T1 - The Interplay of Aldebaran and RoboCup JF - KI - Künstliche Intelligenz Y1 - 2016 U6 - http://dx.doi.org/10.1007/s13218-016-0440-1 SN - 1610-1987 VL - 30 IS - 3-4 SP - 325 EP - 326 PB - Springer CY - Berlin ER - TY - JOUR A1 - Schmidt, K. A1 - Forkmann, K. A1 - Sinke, C. A1 - Gratz, M. A1 - Bitz, Andreas A1 - Bingel, U. T1 - The differential effect of trigeminal vs. peripheral pain stimulation on visual processing and memory encoding is influenced by pain-related fear JF - NeuroImage N2 - Compared to peripheral pain, trigeminal pain elicits higher levels of fear, which is assumed to enhance the interruptive effects of pain on concomitant cognitive processes. In this fMRI study we examined the behavioral and neural effects of trigeminal (forehead) and peripheral (hand) pain on visual processing and memory encoding. Cerebral activity was measured in 23 healthy subjects performing a visual categorization task that was immediately followed by a surprise recognition task. During the categorization task subjects received concomitant noxious electrical stimulation on the forehead or hand. Our data show that fear ratings were significantly higher for trigeminal pain. Categorization and recognition performance did not differ between pictures that were presented with trigeminal and peripheral pain. However, object categorization in the presence of trigeminal pain was associated with stronger activity in task-relevant visual areas (lateral occipital complex, LOC), memory encoding areas (hippocampus and parahippocampus) and areas implicated in emotional processing (amygdala) compared to peripheral pain. Further, individual differences in neural activation between the trigeminal and the peripheral condition were positively related to differences in fear ratings between both conditions. Functional connectivity between amygdala and LOC was increased during trigeminal compared to peripheral painful stimulation. Fear-driven compensatory resource activation seems to be enhanced for trigeminal stimuli, presumably due to their exceptional biological relevance. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.neuroimage.2016.03.026 SN - 1053-8119 VL - 134 SP - 386 EP - 395 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Knobe, M. A1 - Giesen, M. A1 - Plate, S. A1 - Gradl-Dietsch, G. A1 - Buecking, B. A1 - Eschbach, D. A1 - Laack, Walter van A1 - Pape, H.-C. T1 - The Aachen mobility and balance index to measure physiological falls risk: a comparison with the Tinetti POMA scale JF - European Journal Of Trauma And Emergency Surgery N2 - Purpose The most commonly used mobility assessments for screening risk of falls among older adults are rating scales such as the Tinetti performance oriented mobility assessment (POMA). However, its correlation with falls is not always predictable and disadvantages of the scale include difficulty to assess many of the items on a 3-point scale and poor specificity. The purpose of this study was to describe the ability of the new Aachen Mobility and Balance Index (AMBI) to discriminate between subjects with a fall history and subjects without such events in comparison to the Tinetti POMA Scale. Methods For this prospective cohort study, 24 participants in the study group and 10 in the control group were selected from a population of patients in our hospital who had met the stringent inclusion criteria. Both groups completed the Tinetti POMA Scale (gait and balance component) and the AMBI (tandem stance, tandem walk, ten-meter-walk-test, sit-to-stand with five repetitions, 360° turns, timed-up-and-go-test and measurement of the dominant hand grip strength). A history of falls and hospitalization in the past year were evaluated retrospectively. The relationships among the mobility tests were examined with Bland–Altmananalysis. Receiver-operated characteristics curves, sensitivity and specificity were calculated. Results The study showed a strong negative correlation between the AMBI (17 points max., highest fall risk) and Tinetti POMA Scale (28 points max., lowest fall risk; r = −0.78, p < 0.001) with an excellent discrimination between community-dwelling older people and a younger control group. However, there were no differences in any of the mobility and balance measurements between participants with and without a fall history with equal characteristics in test comparison (AMBI vs. Tinetti POMA Scale: AUC 0.570 vs. 0.598; p = 0.762). The Tinetti POMA Scale (cut-off <20 points) showed a sensitivity of 0.45 and a specificity of 0.69, the AMBI a sensitivity of 0.64 and a specificity of 0.46 (cut-off >5 points). Conclusion The AMBI comprises mobility and balance tasks with increasing difficulty as well as a measurement of the dominant hand-grip strength. Its ability to identify fallers was comparable to the Tinetti POMA Scale. However, both measurement sets showed shortcomings in discrimination between fallers and non-fallers based on a self-reported retrospective falls-status. KW - Tinetti test KW - Mobility KW - Mobility tests KW - Ground-level falls KW - Elderly KW - Fall prevention KW - Co-managed care KW - Balance Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00068-016-0693-2 SN - 1863-9941 VL - 42 IS - 5 SP - 537 EP - 545 PB - Springer CY - Berlin ER - TY - JOUR A1 - Al-Kaidy, Huschyar A1 - Tippkötter, Nils T1 - Superparamagnetic hydrophobic particles as shell material for digital microfluidic droplets and proof-of-principle reaction assessments with immobilized laccase JF - Engineering in Life Sciences N2 - In the field of biotechnology and molecular biology, the use of small liquid volumes has significant advantages. In particular, screening and optimization runs with acceptable amounts of expensive and hardly available catalysts, reagents, or biomolecules are feasible with microfluidic technologies. The presented new microfluidic system is based on the inclusion of small liquid volumes by a protective shell of magnetizable microparticles. Hereby, discrete aqueous microreactor drops with volumes of 1–30 μL can be formed on a simple planar surface. A digital movement and manipulation of the microreactor is performed by overlapping magnetic forces. The magnetic forces are generated by an electrical coil matrix positioned below a glass plate. With the new platform technology, several discrete reaction compartments can be moved simultaneously on one surface. Due to the magnetic fields, the reactors can even be merged to initiate reactions by mixing or positioned above surface-immobilized catalysts and then opened by magnetic force. Comparative synthesis routes of the magnetizable shell particles and superhydrophobic glass slides including their performance and stability with the reaction platform are described. The influence of diffusive mass transport during the catalyzed reaction is discussed by evaluation finite element model of the microreactor. Furthermore, a first model dye reaction of the enzyme laccase has been established. Y1 - 2016 U6 - http://dx.doi.org/10.1002/elsc.201400124 VL - 16 IS - 3 SP - 222 EP - 230 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Turaliyeva, M. A1 - Yeshibaev, A. A1 - Saparbekova, A. A1 - Akynova, L. A1 - Abildayeva, R. A1 - Sadenova, M. A1 - Sartayeva, K. A1 - Schieffer, Andre A1 - Digel, Ilya T1 - Species composition and injuriousness of stranger xylophilous fauna affecting indigenous urban dendroflora of Central Asia JF - Asian journal of microbiology, biotechnology & environmental sciences : AJMBES N2 - At the present time, one of the most serious environmental problems of Central Asia and South Kazakhstan is the ongoing large-scale deterioration of principal urban tree populations. Several major centers of massive spread of invasive plant pests have been found in urban dendroflora of this region. The degree of damage of seven most wide-spread aboriginal tree species was found to range from 21.4±1.1 to 85.4±1.8%. In particular, the integrity of the native communities of sycamore (Platanus spp.), willow (Salix spp.), poplar (Populus spp.) and elm (Ulmus spp.) is highly endangered. Our taxonomic analysis of the most dangerous tree pests of the region has revealed them as neobiontic xylophilous insects such as Cossus cossus L. (Order: Lepidoptera L.) Monochamus urussovi Fisch., Monochamus sutor L., Acanthocinus aedelis L. and Ñetonia aureate L. (Order: Coleoptera L.). We relate the origin of this threatening trend with the import of industrial wood in the mid 90’s of the last century that was associated with high degree of the constructional work in the region. Because of the absence of efficient natural predators of the pest species, the application of microbiological methods of the pest control and limitation is suggested. Y1 - 2016 SN - 0972-3005 VL - 18 IS - 2 SP - 359 EP - 366 PB - EM International ER - TY - JOUR A1 - Peloni, Alessandro A1 - Ceriotti, Matteo A1 - Dachwald, Bernd T1 - Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission JF - Journal of Guidance, Control, and Dynamics N2 - The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology. Y1 - 2016 U6 - http://dx.doi.org/10.2514/1.G000470 SN - 0731-5090 VL - 39 IS - 12 SP - 2712 EP - 2724 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Hackl, Michael A1 - Kahmann, Stephanie Lucina A1 - Wegmann, Kilian A1 - Ries, Christian A1 - Staat, Manfred A1 - Müller, Lars-Peter T1 - Shortening osteotomy of the proximal radius — a treatment option for isolated osteoarthritis of the lateral column of the elbow joint? JF - Knee surgery, sports traumatology, arthroscopy N2 - Treatment of posttraumatic osteoarthritis of the radial column of the elbow joint remains a challenging yet common issue. While partial joint replacement leads to high revision rates, radial head excision has shown to severely increase joint instability. Shortening osteotomy of the radius could be an option to decrease the contact pressure of the radiohumeral joint and thereby pain levels without causing valgus instability. Hence, the aim of this biomechanical study was to evaluate the effects of radial shortening on axial load distribution and valgus stability of the elbow joint. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4080-7 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 128 EP - 129 PB - Springer CY - Berlin ER - TY - JOUR A1 - Valero, Daniel A1 - Bung, Daniel B. T1 - Sensitivity of turbulent Schmidt number and turbulence model to simulations of jets in crossflow JF - Environmental Modelling and Software N2 - Environmental discharges have been traditionally designed by means of cost-intensive and time-consuming experimental studies. Some extensively validated models based on an integral approach have been often employed for water quality problems, as recommended by USEPA (i.e.: CORMIX). In this study, FLOW-3D is employed for a full 3D RANS modelling of two turbulent jet-to-crossflow cases, including free surface jet impingement. Results are compared to both physical modelling and CORMIX to better assess model performance. Turbulence measurements have been collected for a better understanding of turbulent diffusion's parameter sensitivity. Although both studied models are generally able to reproduce jet trajectory, jet separation downstream of the impingement has been reproduced only by RANS modelling. Additionally, concentrations are better reproduced by FLOW-3D when the proper turbulent Schmidt number is used. This study provides a recommendation on the selection of the turbulence model and the turbulent Schmidt number for future outfall structures design studies. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.envsoft.2016.04.030 SN - 1364-8152 (electronic) VL - 82 SP - 218 EP - 228 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wu, Chunsheng A1 - Poghossian, Arshak A1 - Bronder, Thomas A1 - Schöning, Michael Josef T1 - Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor JF - Sensors and Actuators B: Chemical N2 - A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules. KW - Layer-by-layer adsorption KW - Poly(allylamine hydrochloride) KW - Label-free detection KW - DNA biosensor KW - LAPS KW - Field effect Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.snb.2016.02.004 SN - 0925-4005 IS - 229 SP - 506 EP - 512 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Dikta, Gerhard A1 - Reißel, Martin A1 - Harlaß, Carsten T1 - Semi-parametric survival function estimators deduced from an identifying Volterra type integral equation JF - Journal of multivariate analysis N2 - 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. KW - Volterra integral equation KW - Product-integration KW - Asymptotic efficiency KW - Semi-parametric random censorship model KW - Censored data KW - Survival analysis Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.jmva.2016.02.008 IS - 147 SP - 273 EP - 284 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rieper, Harald A1 - Gebhardt, Andreas A1 - Stucker, Brent T1 - Selective Laser Melting of the Eutectic Silver-Copper Alloy Ag 28 wt % Cu JF - RTejournal - Forum für Rapid Technologie N2 - The aim of this work was to perform a detailed investigation of the use of Selective Laser Melting (SLM) technology to process eutectic silver-copper alloy Ag 28 wt. % Cu (also called AgCu28). The processing occurred with a Realizer SLM 50 desktop machine. The powder analysis (SEM-topography, EDX, particle distribution) was reported as well as the absorption rates for the near-infrared (NIR) spectrum. Microscope imaging showed the surface topography of the manufactured parts. Furthermore, microsections were conducted for the analysis of porosity. The Design of Experiments approach used the response surface method in order to model the statistical relationship between laser power, spot distance and pulse time. KW - SLM KW - Response Surface Method KW - Porositat KW - Eutectic Silver Copper alloy KW - Additive Manufacturing Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?nbn:de:0009-2-44141 SN - 1614-0923 VL - 13 ER - TY - JOUR A1 - Mykoniou, Konstantin A1 - Butenweg, Christoph A1 - Holtschoppen, Britta A1 - Klinkel, Sven T1 - Seismic response analysis of adjacent liquid-storage tanks JF - Earthquake engineering and structural dynamics N2 - A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank-liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross-interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell-liquid-soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock. KW - liquid-structure interaction KW - seismic response KW - impulsive effects KW - liquid-storage tank KW - structure-soil-structure interaction Y1 - 2016 U6 - http://dx.doi.org/10.1002/eqe.2726 SN - 1096-9845 (E-Journal); 0098-8847 (Print) VL - 45 IS - 11 SP - 1779 EP - 1796 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Frotscher, Ralf A1 - Muanghong, Danita A1 - Dursun, Gözde A1 - Goßmann, Matthias A1 - Temiz Artmann, Aysegül A1 - Staat, Manfred T1 - Sample-specific adaption of an improved electro-mechanical model of in vitro cardiac tissue JF - Journal of Biomechanics N2 - We present an electromechanically coupled computational model for the investigation of a thin cardiac tissue construct consisting of human-induced pluripotent stem cell-derived atrial, ventricular and sinoatrial cardiomyocytes. The mechanical and electrophysiological parts of the finite element model, as well as their coupling are explained in detail. The model is implemented in the open source finite element code Code_Aster and is employed for the simulation of a thin circular membrane deflected by a monolayer of autonomously beating, circular, thin cardiac tissue. Two cardio-active drugs, S-Bay K8644 and veratridine, are applied in experiments and simulations and are investigated with respect to their chronotropic effects on the tissue. These results demonstrate the potential of coupled micro- and macroscopic electromechanical models of cardiac tissue to be adapted to experimental results at the cellular level. Further model improvements are discussed taking into account experimentally measurable quantities that can easily be extracted from the obtained experimental results. The goal is to estimate the potential to adapt the presented model to sample specific cell cultures. KW - hiPS cardiomyocytes KW - Homogenization KW - Hodgkin–Huxley models KW - Frequency adaption KW - Electromechanical modeling KW - Drug simulation KW - Computational biomechanics KW - Cardiac tissue Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.jbiomech.2016.01.039 SN - 0021-9290 (Print) SN - 1873-2380 (Online) VL - 49 IS - 12 SP - 2428 EP - 2435 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Albanna, W. A1 - Conzen, C. A1 - Weiss, M. A1 - Clusmann, H. A1 - Fuest, M. A1 - Mueller, M. A1 - Brockmann, M.A. A1 - Vilser, W. A1 - Schmidt-Trucksäss, A. A1 - Hoellig, A. A1 - Seiz, M. A1 - Thomé, C. A1 - Kotliar, Konstantin A1 - Schubert, G.A. T1 - Retinal Vessel Analysis (RVA) in the context of subarachnoid hemorrhage: A proof of concept study JF - PLoS ONE N2 - Background Timely detection of impending delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is essential to improve outcome, but poses a diagnostic challenge. Retinal vessels as an embryological part of the intracranial vasculature are easily accessible for analysis and may hold the key to a new and non-invasive monitoring technique. This investigation aims to determine the feasibility of standardized retinal vessel analysis (RVA) in the context of SAH. Methods In a prospective pilot study, we performed RVA in six patients awake and cooperative with SAH in the acute phase (day 2–14) and eight patients at the time of follow-up (mean 4.6±1.7months after SAH), and included 33 age-matched healthy controls. Data was acquired using a manoeuvrable Dynamic Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and neurovascular coupling. Results Image quality was satisfactory in the majority of cases (93.3%). In the acute phase after SAH, retinal arteries were significantly dilated when compared to the control group (124.2±4.3MU vs 110.9±11.4MU, p<0.01), a difference that persisted to a lesser extent in the later stage of the disease (122.7±17.2MU, p<0.05). Testing for neurovascular coupling showed a trend towards impaired primary vasodilation and secondary vasoconstriction (p = 0.08, p = 0.09 resp.) initially and partial recovery at the time of follow-up, indicating a relative improvement in a time-dependent fashion. Conclusion RVA is technically feasible in patients with SAH and can detect fluctuations in vessel diameter and autoregulation even in less severely affected patients. Preliminary data suggests potential for RVA as a new and non-invasive tool for advanced SAH monitoring, but clinical relevance and prognostic value will have to be determined in a larger cohort. Y1 - 2016 U6 - http://dx.doi.org/10.1371/journal.pone.0158781 SN - 1932-6203 VL - 11 IS - 7 PB - PLOS CY - San Francisco ER - TY - JOUR A1 - Hackl, Michael A1 - Leschinger, T. A1 - Staat, Manfred A1 - Müller, Lars-Peter A1 - Wegmann, Kilian T1 - Reconstruction of the interosseous membrane in the Essex Lopresti lesion — a biomechanical evaluation JF - Knee surgery, sports traumatology, arthroscopy N2 - Surgical reconstruction of the interosseous membrane (IOM) could restore longitudinal forearm stability to avoid persisting disability due to capituloradial and ulnocarpal impingement in Essex Lopresti lesions. This biomechanical study aimed to assess longitudinal forearm stability of intact specimens, after sectioning of the IOM and after reconstruction with a TightRope construct using either a single or double bundle technique. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4080-7 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 130 EP - 131 PB - Springer CY - Berlin ER -