@article{KronhardtAlexopoulosReisseletal.2014, author = {Kronhardt, Valentina and Alexopoulos, Spiros and Reißel, Martin and Sattler, Johannes Christoph and Hoffschmidt, Bernhard and H{\"a}nel, Matthias and Doerbeck, Till}, title = {High-temperature thermal storage system for solar tower power plants with open-volumetric air receiver simulation and energy balancing of a discretized model}, series = {Energy procedia}, volume = {49}, journal = {Energy procedia}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1876-6102 (E-Journal) ; 1876-6102 (Print)}, doi = {10.1016/j.egypro.2014.03.094}, pages = {870 -- 877}, year = {2014}, abstract = {This paper describes the modeling of a high-temperature storage system for an existing solar tower power plant with open volumetric receiver technology, which uses air as heat transfer medium (HTF). The storage system model has been developed in the simulation environment Matlab/Simulink®. The storage type under investigation is a packed bed thermal energy storage system which has the characteristics of a regenerator. Thermal energy can be stored and discharged as required via the HTF air. The air mass flow distribution is controlled by valves, and the mass flow by two blowers. The thermal storage operation strategy has a direct and significant impact on the energetic and economic efficiency of the solar tower power plants.}, language = {en} } @article{HandtkeSchroeterJuergenetal.2014, author = {Handtke, Stefan and Schroeter, Rebecca and J{\"u}rgen, Britta and Methling, Karen and Schl{\"u}ter, Rabea and Albrecht, Dirk and Hijum, Sacha A. F. T. van and Bongaerts, Johannes and Maurer, Karl-Heinz and Lalk, Michael and Schweder, Thomas and Hecker, Michael and Voigt, Birgit}, title = {Bacillus pumilus reveals a remarkably high resistance to hydrogen peroxide provoked oxidative stress}, series = {PLOS one}, volume = {9}, journal = {PLOS one}, number = {1}, publisher = {PLOS}, address = {San Francisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0085625}, pages = {e85625}, year = {2014}, abstract = {Bacillus pumilus is characterized by a higher oxidative stress resistance than other comparable industrially relevant Bacilli such as B. subtilis or B. licheniformis. In this study the response of B. pumilus to oxidative stress was investigated during a treatment with high concentrations of hydrogen peroxide at the proteome, transcriptome and metabolome level. Genes/proteins belonging to regulons, which are known to have important functions in the oxidative stress response of other organisms, were found to be upregulated, such as the Fur, Spx, SOS or CtsR regulon. Strikingly, parts of the fundamental PerR regulon responding to peroxide stress in B. subtilis are not encoded in the B. pumilus genome. Thus, B. pumilus misses the catalase KatA, the DNA-protection protein MrgA or the alkyl hydroperoxide reductase AhpCF. Data of this study suggests that the catalase KatX2 takes over the function of the missing KatA in the oxidative stress response of B. pumilus. The genome-wide expression analysis revealed an induction of bacillithiol (Cys-GlcN-malate, BSH) relevant genes. An analysis of the intracellular metabolites detected high intracellular levels of this protective metabolite, which indicates the importance of bacillithiol in the peroxide stress resistance of B. pumilus.}, language = {en} } @article{FrotscherStaat2014, author = {Frotscher, Ralf and Staat, Manfred}, title = {Stresses produced by different textile mesh implants in a tissue equivalent}, series = {BioNanoMaterials}, volume = {15}, journal = {BioNanoMaterials}, number = {1-2}, publisher = {De Gruyter}, address = {Berlin}, issn = {2191-4672 (E-Journal); 2193-066X (E-Journal); 0011-8656 (Print); 1616-0177 (Print); 2193-0651 (Print)}, doi = {10.1515/bnm-2014-0003}, pages = {25 -- 30}, year = {2014}, abstract = {Two single-incision mini-slings used for treating urinary incontinence in women are compared with respect to the stresses they produce in their surrounding tissue. In an earlier paper we experimentally observed that these implants produce considerably different stress distributions in a muscle tissue equivalent. Here we perform 2D finite element analyses to compare the shear stresses and normal stresses in the tissue equivalent for the two meshes and to investigate their failure behavior. The results clearly show that the Gynecare TVT fails for increasing loads in a zipper-like manner because it gradually debonds from the surrounding tissue. Contrary to that, the tissue at the ends of the DynaMesh-SIS direct may rupture but only at higher loads. The simulation results are in good agreement with the experimental observations thus the computational model helps to interpret the experimental results and provides a tool for qualitative evaluation of mesh implants.}, language = {en} } @article{AlhwarinFerreinScholl2014, author = {Alhwarin, Faraj and Ferrein, Alexander and Scholl, Ingrid}, title = {IR stereo kinect: improving depth images by combining structured light with IR stereo}, pages = {1 -- 9}, year = {2014}, language = {en} } @article{LeandroBungCarvalho2014, author = {Leandro, J. and Bung, Daniel Bernhard and Carvalho, R.}, title = {Measuring void fraction and velocity fields of a stepped spillway for skimming flow using non-intrusive methods}, series = {Experiments in fluids}, journal = {Experiments in fluids}, number = {55}, publisher = {Springer Nature}, address = {Heidelberg}, issn = {0723-4864 (Print) ; 1432-1114 (Online)}, doi = {10.1007/s00348-014-1732-6}, pages = {Art. 1732}, year = {2014}, language = {en} } @article{KueppersSteffenHellmuthetal.2014, author = {K{\"u}ppers, Tobias and Steffen, Victoria and Hellmuth, Hendrik and O'Connell, Timothy and Bongaerts, Johannes and Maurer, Karl-Heinz and Wiechert, Wolfgang}, title = {Developing a new production host from a blueprint: Bacillus pumilus as an industrial enzyme producer}, series = {Microbial cell factories}, volume = {13}, journal = {Microbial cell factories}, publisher = {BioMed Central}, address = {London}, issn = {1475-2859 (E-Journal)}, doi = {10.1186/1475-2859-13-46}, pages = {Article No. 46}, year = {2014}, language = {en} } @article{PhamStaat2014, author = {Pham, Phu Tinh and Staat, Manfred}, title = {FEM-based shakedown analysis of hardening structures}, series = {Asia Pacific journal on computational engineering}, journal = {Asia Pacific journal on computational engineering}, number = {1}, publisher = {SpringerOpen}, address = {Berlin}, issn = {2196-1166 (E-Journal)}, doi = {10.1186/2196-1166-1-4}, pages = {Article No. 4}, year = {2014}, abstract = {This paper develops a new finite element method (FEM)-based upper bound algorithm for limit and shakedown analysis of hardening structures by a direct plasticity method. The hardening model is a simple two-surface model of plasticity with a fixed bounding surface. The initial yield surface can translate inside the bounding surface, and it is bounded by one of the two equivalent conditions: (1) it always stays inside the bounding surface or (2) its centre cannot move outside the back-stress surface. The algorithm gives an effective tool to analyze the problems with a very high number of degree of freedom. Our numerical results are very close to the analytical solutions and numerical solutions in literature.}, language = {en} } @article{HaagZontarSchleupenetal.2014, author = {Haag, S. and Zontar, D. and Schleupen, Josef and M{\"u}ller, T. and Brecher, C.}, title = {Chain of refined perception in self-optimizing assembly of micro-optical systems}, series = {Journal of sensors and sensor systems}, volume = {3}, journal = {Journal of sensors and sensor systems}, number = {1}, publisher = {Copernicus Publ.}, address = {G{\"o}ttingen}, issn = {2194-878X}, doi = {10.5194/jsss-3-87-2014}, pages = {87 -- 95}, year = {2014}, abstract = {Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements - especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.}, language = {en} } @article{ScheerWolf2014, author = {Scheer, Nico and Wolf, C. Roland}, title = {Genetically humanized mouse models of drug metabolizing enzymes and transporters and their applications}, series = {Xenobiotica}, volume = {44}, journal = {Xenobiotica}, number = {2}, publisher = {Taylor \& Francis}, address = {Abingdon}, issn = {1366-5928}, doi = {10.3109/00498254.2013.815831}, pages = {96 -- 108}, year = {2014}, abstract = {1. Drug metabolizing enzymes and transporters play important roles in the absorption, metabolism, tissue distribution and excretion of various compounds and their metabolites and thus can significantly affect their efficacy and safety. Furthermore, they can be involved in drug-drug interactions which can result in adverse responses, life-threatening toxicity or impaired efficacy. Significant species differences in the interaction of compounds with drug metabolizing enzymes and transporters have been described. 2. In order to overcome the limitation of animal models in accurately predicting human responses, a large variety of mouse models humanized for drug metabolizing enzymes and to a lesser extent drug transporters have been created. 3. This review summarizes the literature describing these mouse models and their key applications in studying the role of drug metabolizing enzymes and transporters in drug bioavailability, tissue distribution, clearance and drug-drug interactions as well as in human metabolite testing and risk assessment. 4. Though such humanized mouse models have certain limitations, there is great potential for their use in basic research and for testing and development of new medicines. These limitations and future potentials will be discussed.}, language = {en} } @article{Bernecker2014, author = {Bernecker, Andreas}, title = {Do politicians shirk when reelection is certain? Evidence from the German parliament}, series = {European Journal of Political Economy}, volume = {36}, journal = {European Journal of Political Economy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0176-2680}, doi = {10.1016/j.ejpoleco.2014.07.001}, pages = {55 -- 70}, year = {2014}, abstract = {Does stiffer electoral competition reduce political shirking? For a micro-analysis of this question, I construct a new data set spanning the years 2005 to 2012 covering biographical and political information about German Members of Parliament (MPs), including their attendance rates in voting sessions. For the parliament elected in 2009, I show that indeed opposition party MPs who expect to face a close race in their district show significantly and relevantly lower absence rates in parliament beforehand. MPs of governing parties seem not to react significantly to electoral competition. These results are confirmed by an analysis of the parliament elected in 2005, by several robustness checks, and also by employing an instrumental variable strategy exploiting convenient peculiarities of the German electoral system. The study also shows how MPs elected via party lists react to different levels of electoral competition.}, language = {en} }