@article{EngelGemuendeHoltmannetal.2019, author = {Engel, Mareike and Gem{\"u}nde, Andre and Holtmann, Dirk and M{\"u}ller-Renno, Christine and Ziegler, Christiane and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Clostridium acetobutylicum's connecting world: cell appendage formation in bioelectrochemical systems}, series = {ChemElectroChem}, journal = {ChemElectroChem}, number = {Accepted Article}, publisher = {Wiley}, address = {Weinheim}, issn = {2196-0216}, doi = {10.1002/celc.201901656}, year = {2019}, language = {en} } @article{TippkoetterRoth2020, author = {Tippk{\"o}tter, Nils and Roth, Jasmine}, title = {Purified Butanol from Lignocellulose - Solvent-Impregnated Resins for an Integrated Selective Removal}, series = {Chemie Ingenieur Technik}, volume = {92}, journal = {Chemie Ingenieur Technik}, number = {11}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1522-2640}, doi = {10.1002/cite.202000200}, pages = {1741 -- 1751}, year = {2020}, abstract = {In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space-time yield. Thermal separation is not feasible due to the boiling point of n-butanol. As an integrated and selective solid-liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed-bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once.}, language = {en} } @article{ScheerWilson2016, author = {Scheer, Nico and Wilson, Ian D.}, title = {A comparison between genetically humanized and chimeric liver humanized mouse models for studies in drug metabolism and toxicity}, series = {Drug Discovery Today}, volume = {21}, journal = {Drug Discovery Today}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-6446}, doi = {10.1016/j.drudis.2015.09.002}, pages = {250 -- 263}, year = {2016}, abstract = {Mice that have been genetically humanized for proteins involved in drug metabolism and toxicity and mice engrafted with human hepatocytes are emerging and promising in vivo models for an improved prediction of the pharmacokinetic, drug-drug interaction and safety characteristics of compounds in humans. The specific advantages and disadvantages of these models should be carefully considered when using them for studies in drug discovery and development. Here, an overview on the corresponding genetically humanized and chimeric liver humanized mouse models described to date is provided and illustrated with examples of their utility in drug metabolism and toxicity studies. We compare the strength and weaknesses of the two different approaches, give guidance for the selection of the appropriate model for various applications and discuss future trends and perspectives.}, 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{ScheerWolf2013, author = {Scheer, Nico and Wolf, C. Roland}, title = {Xenobiotic receptor humanized mice and their utility}, series = {Drug Metabolism Reviews}, journal = {Drug Metabolism Reviews}, number = {1}, publisher = {Taylor \& Francis}, address = {London}, issn = {1097-9883}, doi = {10.3109/03602532.2012.738687}, pages = {110 -- 121}, year = {2013}, language = {en} } @article{HendersonScheerWolf2009, author = {Henderson, Colin J. and Scheer, Nico and Wolf, C. Roland}, title = {Advances in the generation of mouse models to elucidate the pathways of drug metabolism in rodents and man}, series = {Expert Review of Clinical Pharmacology}, volume = {2}, journal = {Expert Review of Clinical Pharmacology}, number = {2}, publisher = {Taylor \& Francis}, address = {London}, issn = {1751-2441}, doi = {10.1586/17512433.2.2.105}, pages = {105 -- 109}, year = {2009}, language = {en} } @article{StanleyHorsburghRossetal.2009, author = {Stanley, Lesley A. and Horsburgh, Brian C. and Ross, Jillian and Scheer, Nico and Wolf, C. Roland}, title = {Drug transporters: Gatekeepers controlling access of xenobiotics to the cellular interior}, series = {Drug Metabolism Reviews}, volume = {41}, journal = {Drug Metabolism Reviews}, number = {1}, publisher = {Taylor \& Francis}, address = {London}, issn = {1097-9883}, doi = {10.1080/03602530802605040}, pages = {27 -- 65}, year = {2009}, language = {en} } @article{StanleyHorsburghRossetal.2006, author = {Stanley, Lesley A. and Horsburgh, Brian C. and Ross, Jillian and Scheer, Nico and Wolf, C. Roland}, title = {Nuclear Receptors which play a pivotal role in drug disposition and chemical toxicity}, series = {Drug Metabolism Reviews}, volume = {38}, journal = {Drug Metabolism Reviews}, number = {3}, issn = {1097-9883}, doi = {10.1080/03602530600786232}, pages = {515 -- 597}, year = {2006}, language = {en} } @incollection{SamuelssonScheerWilsonetal.2017, author = {Samuelsson, K. and Scheer, Nico and Wilson, I. and Wolf, C.R. and Henderson, C.J.}, title = {Genetically Humanized Animal Models}, series = {Comprehensive Medicinal Chemistry III. 3rd Edition}, booktitle = {Comprehensive Medicinal Chemistry III. 3rd Edition}, editor = {Chackalamannil, Samuel}, publisher = {Elsevier}, address = {Saint Louis}, isbn = {978-0-12-803201-5}, doi = {10.1016/B978-0-12-409547-2.12376-5}, pages = {130 -- 149}, year = {2017}, abstract = {Genetically humanized mice for proteins involved in drug metabolism and toxicity and mice engrafted with human hepatocytes are emerging as promising in vivo models for improved prediction of the pharmacokinetic, drug-drug interaction, and safety characteristics of compounds in humans. This is an overview on the genetically humanized and chimeric liver-humanized mouse models, which are illustrated with examples of their utility in drug metabolism and toxicity studies. The models are compared to give guidance for selection of the most appropriate model by highlighting advantages and disadvantages to be carefully considered when used for studies in drug discovery and development.}, language = {en} } @incollection{ScheerChuSalphatietal.2016, author = {Scheer, Nico and Chu, Xiaoyan and Salphati, Laurent and Zamek-Gliszczynski, Maciej J.}, title = {Knockout and humanized animal models to study membrane transporters in drug development}, series = {Drug Transporters: Volume 1: Role and Importance in ADME and Drug Development}, booktitle = {Drug Transporters: Volume 1: Role and Importance in ADME and Drug Development}, editor = {Nicholls, Glynis}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, isbn = {978-1-78262-379-3}, doi = {10.1039/9781782623793-00298}, pages = {298 -- 332}, year = {2016}, language = {en} } @incollection{WolfKapelyukhScheeretal.2015, author = {Wolf, C. Roland and Kapelyukh, Yury and Scheer, Nico and Henderson, Colin J.}, title = {Application of Humanised and Other Transgenic Models to Predict Human Responses to Drugs}, editor = {Wilson, Alan G. E.}, publisher = {RSC Publ.}, address = {Cambridge}, isbn = {978-1-78262-778-4}, doi = {10.1039/9781782622376-00152}, pages = {152 -- 176}, year = {2015}, abstract = {The use of transgenic animal models has transformed our knowledge of complex biochemical pathways in vivo. It has allowed disease processes to be modelled and used in the development of new disease prevention and treatment strategies. They can also be used to define cell- and tissue-specific pathways of gene regulation. A further major application is in the area of preclinical development where such models can be used to define pathways of chemical toxicity, and the pathways that regulate drug disposition. One major application of this approach is the humanisation of mice for the proteins that control drug metabolism and disposition. Such models can have numerous applications in the development of drugs and in their more sophisticated use in the clinic.}, language = {en} } @incollection{HendersonWolfScheer2009, author = {Henderson, Colin J. and Wolf, C. Roland and Scheer, Nico}, title = {The use of transgenic animals to study drug metabolism}, series = {Handbook of Drug Metabolism. 2nd Edition}, booktitle = {Handbook of Drug Metabolism. 2nd Edition}, editor = {Woolf, Thomas F.}, publisher = {Informa Healthcare}, address = {New York}, isbn = {978-1-4200-7647-9}, pages = {637 -- 658}, year = {2009}, language = {en} } @article{EngelBayerHoltmannetal.2019, author = {Engel, Mareike and Bayer, Hendrik and Holtmann, Dirk and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Flavin secretion of Clostridium acetobutylicum in a bioelectrochemical system - Is an iron limitation involved?}, series = {Bioelectrochemistry}, journal = {Bioelectrochemistry}, number = {In Press, Accepted Manuscript}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1567-5394}, doi = {10.1016/j.bioelechem.2019.05.014}, year = {2019}, language = {en} } @article{ScheerRossRodeetal.2008, author = {Scheer, Nico and Ross, Jillian and Rode, Anja and Zevnik, Branko and Niehaves, Sandra and Faust, Nicole and Wolf, C. Roland}, title = {A novel panel of mouse models to evaluate the role of human pregnane X receptor and constitutive androstane receptor in drug response}, series = {Journal of Clinical Investigation}, volume = {118}, journal = {Journal of Clinical Investigation}, number = {9}, issn = {1558-8238}, doi = {https://doi.org/10.1172/JCI35483}, pages = {3228 -- 3239}, year = {2008}, language = {en} } @article{ScheerKapelyukhMcEwanetal.2012, author = {Scheer, Nico and Kapelyukh, Yury and McEwan, Jillian and Beuger, Vincent and Stanley, Lesley A. and Rode, Anja and Wolf, C. Roland}, title = {Modeling Human Cytochrome P450 2D6 Metabolism and Drug-drug Interaction by a Novel Panel of Knockout and Humanized Mouse Lines}, series = {Molecular Pharmacology}, volume = {81}, journal = {Molecular Pharmacology}, number = {1}, publisher = {ASPET}, address = {Bethesda, Md.}, issn = {1521-0111}, doi = {10.1124/mol.111.075192}, pages = {63 -- 72}, year = {2012}, abstract = {The highly polymorphic human cytochrome P450 2D6 enzyme is involved in the metabolism of up to 25\% of all marketed drugs and accounts for significant individual differences in response to CYP2D6 substrates. Because of the differences in the multiplicity and substrate specificity of CYP2D family members among species, it is difficult to predict pathways of human CYP2D6-dependent drug metabolism on the basis of animal studies. To create animal models that reflect the human situation more closely and that allow an in vivo assessment of the consequences of differential CYP2D6 drug metabolism, we have developed a novel straightforward approach to delete the entire murine Cyp2d gene cluster and replace it with allelic variants of human CYP2D6. By using this approach, we have generated mouse lines expressing the two frequent human protein isoforms CYP2D6.1 and CYP2D6.2 and an as yet undescribed variant of this enzyme, as well as a Cyp2d cluster knockout mouse. We demonstrate that the various transgenic mouse lines cover a wide spectrum of different human CYP2D6 metabolizer phenotypes. The novel humanization strategy described here provides a robust approach for the expression of different CYP2D6 allelic variants in transgenic mice and thus can help to evaluate potential CYP2D6-dependent interindividual differences in drug response in the context of personalized medicine.}, language = {en} } @article{ReugelsBoggettiScheeretal.2006, author = {Reugels, Alexander M. and Boggetti, Barbara and Scheer, Nico and Campos-Ortega, Jos{\´e} A.}, title = {Asymmetric localization of Numb:EGFP in dividing neuroepithelial cells during neurulation in Danio rerio}, series = {Developmental Dynamics}, volume = {235}, journal = {Developmental Dynamics}, number = {4}, issn = {1097-0177}, doi = {10.1002/dvdy.20699}, pages = {934 -- 948}, year = {2006}, language = {en} } @article{HansScheerRiedletal.2004, author = {Hans, Stefan and Scheer, Nico and Riedl, Iris and Weiz{\"a}cker, Elisabeth von and Blader, Patrick and Campos-Ortega, Jos{\´e} A.}, title = {her3, a zebrafish member of the hairy-E(spl) family, is repressed by Notch signalling}, series = {Development}, volume = {131}, journal = {Development}, number = {12}, issn = {1477-9129}, doi = {10.1242/dev.01167}, pages = {2957 -- 2969}, year = {2004}, language = {en} } @article{ScheerRiedlWarrenetal.2002, author = {Scheer, Nico and Riedl, Iris and Warren, J.T. and Kuwada, John Y. and Campos-Ortega, Jos{\´e} A.}, title = {A quantitative analysis of the kinetics of Gal4 activator and effector gene expression in the zebrafish}, series = {Mechanism of Development}, volume = {112}, journal = {Mechanism of Development}, number = {1-2}, issn = {0925-4773}, doi = {10.1016/S0925-4773(01)00621-9}, pages = {9 -- 14}, year = {2002}, language = {en} } @article{LawsonScheerPhametal.2001, author = {Lawson, Nathan D. and Scheer, Nico and Pham, Van N. and Kim, Ceol-Hee and Chitnis, Ajay B. and Campos-Ortega, Jos{\´e} A. and Weinstein, Brant M.}, title = {Notch signaling is required for arterial-venous differentiation during embryonic vascular development}, series = {Development}, volume = {128}, journal = {Development}, number = {19}, issn = {1477-9129}, pages = {3675 -- 3683}, year = {2001}, language = {en} } @article{ScheerGrothHansetal.2001, author = {Scheer, Nico and Groth, Anne and Hans, Stefan and Campos-Ortega, Jos{\´e} A.}, title = {An instructive function for Notch in promoting gliogenesis in the zebrafish retina}, series = {Development}, volume = {128}, journal = {Development}, number = {7}, issn = {0950-1991}, pages = {1099 -- 1107}, year = {2001}, language = {en} } @article{HalbachScheer2000, author = {Halbach, Thorsten and Scheer, Nico}, title = {Transcriptional activation by the PHD finger is inhibited through an adjacent leucine zipper that binds 14-3-3 proteins}, series = {Nucleic Acids Research}, volume = {28}, journal = {Nucleic Acids Research}, number = {18}, issn = {1362-4962}, doi = {10.1093/nar/28.18.3542}, pages = {3542 -- 3550}, year = {2000}, language = {en} } @article{ScheerCamposOrtega1999, author = {Scheer, Nico and Campos-Ortega, Jos{\´e} A.}, title = {Use of the Gal4-UAS technique for targeted gene expression in the zebrafish}, series = {Mechanism of Development}, volume = {80}, journal = {Mechanism of Development}, number = {2}, issn = {0925-4773}, doi = {10.1016/S0925-4773(98)00209-3}, pages = {153 -- 158}, year = {1999}, language = {en} } @article{MoretAlkemadeUpcraftetal.2020, author = {Moret, J.L.T.M. and Alkemade, J. and Upcraft, T.M. and Paulßen, Elisabeth and Wolterbeek, H.T. and Ommen, J.R. van and Denkova, A.G.}, title = {The application of atomic layer deposition in the production of sorbents for ⁹⁹Mo/⁹⁹ᵐTc generator}, series = {Applied Radiation and Isotopes}, volume = {164}, journal = {Applied Radiation and Isotopes}, number = {109266}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0969-8043}, doi = {10.1016/j.apradiso.2020.109266}, pages = {9}, year = {2020}, abstract = {New production routes for ⁹⁹Mo are steadily gaining importance. However, the obtained specific activity is much lower than currently produced by the fission of U-235. To be able to supply hospitals with ⁹⁹Mo/⁹⁹ᵐTc generators with the desired activity, the adsorption capacity of the column material should be increased. In this paper we have investigated whether the gas phase coating technique Atomic Layer Deposition (ALD), which can deposit ultra-thin layers on high surface area materials, can be used to attain materials with high adsorption capacity for ⁹⁹Mo. For this purpose, ALD was applied on a silica-core sorbent material to coat it with a thin layer of alumina. This sorbent material shows to have a maximum adsorption capacity of 120 mg/g and has a ⁹⁹ᵐTc elution efficiency of 55 ± 2\% based on 3 executive elutions.}, language = {en} } @article{SchiedermeierRettnerHeilmannetal.2019, author = {Schiedermeier, Maximilian and Rettner, Cornelius and Heilmann, Marcel and Schneider, Felix and Marz, Martin}, title = {Interference of automotive HV-DC-systems by traction voltage-source-inverters (VSI)}, series = {2019 IEEE Transportation Electrification Conference (ITEC-India)}, journal = {2019 IEEE Transportation Electrification Conference (ITEC-India)}, publisher = {IEEE}, address = {New York}, doi = {10.1109/ITEC-India48457.2019.ITECINDIA2019-37}, pages = {1 -- 6}, year = {2019}, language = {en} } @article{ElMoussaouiTalbiAtmaneetal.2020, author = {El Moussaoui, Noureddine and Talbi, Sofian and Atmane, Ilyas and Kassmi, Khalil and Schwarzer, Klemens and Chayeb, Hamid and Bachiri, Najib}, title = {Feasibility of a new design of a Parabolic Trough Solar Thermal Cooker (PSTC)}, series = {Solar Energy}, volume = {201}, journal = {Solar Energy}, number = {Vol. 201 (May 2020)}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0038-092X}, doi = {10.1016/j.solener.2020.03.079}, pages = {866 -- 871}, year = {2020}, abstract = {In this article, we describe the structure, the functioning, and the tests of parabolic trough solar thermal cooker (PSTC). This oven is designed to meet the needs of rural residents, including Urban, which requires stable cooking temperatures above 200 °C. The cooking by this cooker is based on the concentration of the sun's rays on a glass vacuum tube and heating of the oil circulate in a big tube, located inside the glass tube. Through two small tubes, associated with large tube, the heated oil, rise and heats the pot of cooking pot containing the food to be cooked (capacity of 5 kg). This cooker is designed in Germany and extensively tested in Morocco for use by the inhabitants who use wood from forests. During a sunny day, having a maximum solar radiation around 720 W/m2 and temperature ambient around 26 °C, maximum temperatures recorded of the small tube, the large tube and the center of the pot are respectively: 370 °C, 270 °C and 260 °C. The cooking process with food at high (fries, ..), we show that the cooking oil temperature rises to 200 °C, after 1 h of heating, the cooking is done at a temperature of 120 °C for 20 min. These temperatures are practically stable following variations and decreases in the intensity of irradiance during the day. The comparison of these results with those of the literature shows an improvement of 30-50 \% on the maximum value of the temperature with a heat storage that could reach 60 min of autonomy. All the results obtained show the good functioning of the PSTC and the feasibility of cooking food at high temperature (>200 °C).}, language = {en} } @article{MuschallikKippReckeretal.2020, author = {Muschallik, Lukas and Kipp, Carina Ronja and Recker, Inga and Bongaerts, Johannes and Pohl, Martina and Gelissen, Melanie and Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Siegert, Petra}, title = {Synthesis of α-hydroxy ketones and vicinal diols with the Bacillus licheniformis DSM 13T butane-2, 3-diol dehydrogenase}, series = {Journal of Biotechnology}, volume = {202}, journal = {Journal of Biotechnology}, number = {Vol. 324}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {2590-1559}, doi = {10.1016/j.jbiotec.2020.09.016}, pages = {61 -- 70}, year = {2020}, abstract = {The enantioselective synthesis of α-hydroxy ketones and vicinal diols is an intriguing field because of the broad applicability of these molecules. Although, butandiol dehydrogenases are known to play a key role in the production of 2,3-butandiol, their potential as biocatalysts is still not well studied. Here, we investigate the biocatalytic properties of the meso-butanediol dehydrogenase from Bacillus licheniformis DSM 13T (BlBDH). The encoding gene was cloned with an N-terminal StrepII-tag and recombinantly overexpressed in E. coli. BlBDH is highly active towards several non-physiological diketones and α-hydroxyketones with varying aliphatic chain lengths or even containing phenyl moieties. By adjusting the reaction parameters in biotransformations the formation of either the α-hydroxyketone intermediate or the diol can be controlled.}, language = {en} } @article{MayerHentschkeHageretal.2017, author = {Mayer, Jan and Hentschke, Reinhard and Hager, Jonathan and Hojdis, Nils and Karimi-Varnaneh, Hossein Ali}, title = {A Nano-Mechanical Instability as Primary Contribution to Rolling Resistance}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, number = {Article number 11275}, publisher = {Springer}, address = {Berlin}, issn = {2045-2322}, year = {2017}, language = {en} } @article{SvaneborgKarimiVarzanehHojdisetal.2016, author = {Svaneborg, Carsten and Karimi-Varzaneh, Hossein Ali and Hojdis, Nils and Fleck, Franz and Everaers, Ralf}, title = {Multiscale approach to equilibrating model polymer melts}, series = {Physical Review E}, volume = {94}, journal = {Physical Review E}, number = {032502}, publisher = {AIP Publishing}, address = {Melville, NY}, issn = {2470-0053}, doi = {10.1103/PhysRevE.94.032502}, year = {2016}, abstract = {We present an effective and simple multiscale method for equilibrating Kremer Grest model polymer melts of varying stiffness. In our approach, we progressively equilibrate the melt structure above the tube scale, inside the tube and finally at the monomeric scale. We make use of models designed to be computationally effective at each scale. Density fluctuations in the melt structure above the tube scale are minimized through a Monte Carlo simulated annealing of a lattice polymer model. Subsequently the melt structure below the tube scale is equilibrated via the Rouse dynamics of a force-capped Kremer-Grest model that allows chains to partially interpenetrate. Finally the Kremer-Grest force field is introduced to freeze the topological state and enforce correct monomer packing. We generate 15 melts of 500 chains of 10.000 beads for varying chain stiffness as well as a number of melts with 1.000 chains of 15.000 monomers. To validate the equilibration process we study the time evolution of bulk, collective, and single-chain observables at the monomeric, mesoscopic, and macroscopic length scales. Extension of the present method to longer, branched, or polydisperse chains, and/or larger system sizes is straightforward.}, language = {en} } @article{SchwabHojdisLacayoetal.2016, author = {Schwab, Lukas and Hojdis, Nils and Lacayo, Jorge and Wilhelm, Manfred}, title = {Fourier-Transform Rheology of Unvulcanized, Carbon Black Filled Styrene Butadiene Rubber}, series = {Macromolecular Materials and Engineering}, volume = {301}, journal = {Macromolecular Materials and Engineering}, number = {4}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1439-2054}, doi = {10.1002/mame.201500356}, pages = {457 -- 468}, year = {2016}, abstract = {Rubber materials filled with reinforcing fillers display nonlinear rheological behavior at small strain amplitudes below γ0 < 0.1. Nevertheless, rheological data are analyzed mostly in terms of linear parameters, such as shear moduli (G′, G″), which loose their physical meaning in the nonlinear regime. In this work styrene butadiene rubber filled with carbon black (CB) under large amplitude oscillatory shear (LAOS) is analyzed in terms of the nonlinear parameter I3/1. Three different CB grades are used and the filler load is varied between 0 and 70 phr. It is found that I3/1(φ) is most sensitive to changes of the total accessible filler surface area at low strain amplitudes (γ0 = 0.32). The addition of up to 70 phr CB leads to an increase of I3/1(φ) by a factor of more than ten. The influence of the measurement temperature on I3/1 is pronounced for CB levels above the percolation threshold.}, language = {en} } @article{HarishWriggersJungketal.2016, author = {Harish, Ajay B. and Wriggers, Peter and Jungk, Juliane and Hojdis, Nils and Recker, Carla}, title = {Mesoscale Constitutive Modeling of Non-Crystallizing Filled Elastomers}, series = {Computational Mechanics}, volume = {57}, journal = {Computational Mechanics}, publisher = {Springer}, address = {Berlin}, issn = {1432-0924}, doi = {10.1007/s00466-015-1251-1}, pages = {653 -- 677}, year = {2016}, abstract = {Elastomers are exceptional materials owing to their ability to undergo large deformations before failure. However, due to their very low stiffness, they are not always suitable for industrial applications. Addition of filler particles provides reinforcing effects and thus enhances the material properties that render them more versatile for applications like tyres etc. However, deformation behavior of filled polymers is accompanied by several nonlinear effects like Mullins and Payne effect. To this day, the physical and chemical changes resulting in such nonlinear effect remain an active area of research. In this work, we develop a heterogeneous (or multiphase) constitutive model at the mesoscale explicitly considering filler particle aggregates, elastomeric matrix and their mechanical interaction through an approximate interface layer. The developed constitutive model is used to demonstrate cluster breakage, also, as one of the possible sources for Mullins effect observed in non-crystallizing filled elastomers.}, language = {en} } @article{HentschkeHagerHojdis2014, author = {Hentschke, Reinhard and Hager, Jonathan and Hojdis, Nils}, title = {Molecular Modeling Approach to the Prediction of Mechanical Properties of Silica-Reinforced Rubbers}, series = {Journal of Applied Polymer Science}, volume = {131}, journal = {Journal of Applied Polymer Science}, number = {18}, publisher = {Wiley}, address = {New York, NY}, issn = {1097-4628}, doi = {10.1002/app.40806}, pages = {1 -- 9}, year = {2014}, abstract = {Recently, we have suggested a nanomechanical model for dissipative loss in filled elastomer networks in the context of the Payne effect. The mechanism is based on a total interfiller particle force exhibiting an intermittent loop, due to the combination of short-range repulsion and dispersion forces with a long-range elastic attraction. The sum of these forces leads, under external strain, to a spontaneous instability of "bonds" between the aggregates in a filler network and attendant energy dissipation. Here, we use molecular dynamics simulations to obtain chemically realistic forces between surface modified silica particles. The latter are combined with the above model to estimate the loss modulus and the low strain storage modulus in elastomers containing the aforementioned filler-compatibilizer systems. The model is compared to experimental dynamic moduli of silica filled rubbers. We find good agreement between the model predictions and the experiments as function of the compatibilizer's molecular structure and its bulk concentration.}, language = {en} } @article{EveraersKarimiVarzanehFlecketal.2020, author = {Everaers, Ralf and Karimi-Varzaneh, Hossein Ali and Fleck, Franz and Hojdis, Nils and Svaneborg, Carsten}, title = {Kremer-Grest Models for Commodity Polymer Melts: Linking Theory, Experiment, and Simulation at the Kuhn Scale}, series = {Macromolecules}, volume = {53}, journal = {Macromolecules}, number = {6}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {1520-5835}, doi = {10.1021/acs.macromol.9b02428}, pages = {1901 -- 1916}, year = {2020}, abstract = {The Kremer-Grest (KG) polymer model is a standard model for studying generic polymer properties in molecular dynamics simulations. It owes its popularity to its simplicity and computational efficiency, rather than its ability to represent specific polymers species and conditions. Here we show that by tuning the chain stiffness it is possible to adapt the KG model to model melts of real polymers. In particular, we provide mapping relations from KG to SI units for a wide range of commodity polymers. The connection between the experimental and the KG melts is made at the Kuhn scale, i.e., at the crossover from the chemistry-specific small scale to the universal large scale behavior. We expect Kuhn scale-mapped KG models to faithfully represent universal properties dominated by the large scale conformational statistics and dynamics of flexible polymers. In particular, we observe very good agreement between entanglement moduli of our KG models and the experimental moduli of the target polymers.}, language = {en} } @article{MeyerHentschkeHageretal.2017, author = {Meyer, Jan and Hentschke, Reinhard and Hager, Jonathan and Hojdis, Nils and Karimi-Varzaneh, Hossein Ali}, title = {Molecular Simulation of Viscous Dissipation due to Cyclic Deformation of a Silica-Silica Contact in Filled Rubber}, series = {Macromolecules}, volume = {50}, journal = {Macromolecules}, number = {17}, issn = {1520-5835}, doi = {10.1021/acs.macromol.7b00947}, pages = {6679 -- 6689}, year = {2017}, language = {en} } @article{HagerHentschkeHojdisetal.2015, author = {Hager, Jonathan and Hentschke, Reinhard and Hojdis, Nils and Karimi-Varzaneh, Hossein Ali}, title = {Computer Simulation of Particle-Particle Interaction in a Model Polymer Nanocomposite}, series = {Macromolecules}, volume = {48}, journal = {Macromolecules}, number = {24}, issn = {1520-5835}, doi = {10.1021/acs.macromol.5b01864}, pages = {9039 -- 9049}, year = {2015}, language = {en} } @article{WallerBraunHojdisetal.2007, author = {Waller, Mark P. and Braun, Heiko and Hojdis, Nils and B{\"u}hl, Michael}, title = {Geometries of Second-Row Transition-Metal Complexes from Density-Functional Theory}, series = {Journal of Chemical Theory and Computation}, volume = {3}, journal = {Journal of Chemical Theory and Computation}, number = {6}, issn = {1549-9626}, doi = {10.1021/ct700178y}, pages = {2234 -- 2242}, year = {2007}, language = {en} } @article{SvaneborgKarimiVarzanehHojdisetal.2018, author = {Svaneborg, Carsten and Karimi-Varzaneh, Hossein Ali and Hojdis, Nils and Fleck, Franz and Everaers, Ralf}, title = {Kremer-Grest Models for Universal Properties of Specific Common Polymer Species}, series = {Soft Condensed Matter}, journal = {Soft Condensed Matter}, number = {1606.05008}, year = {2018}, abstract = {The Kremer-Grest (KG) bead-spring model is a near standard in Molecular Dynamic simulations of generic polymer properties. It owes its popularity to its computational efficiency, rather than its ability to represent specific polymer species and conditions. Here we investigate how to adapt the model to match the universal properties of a wide range of chemical polymers species. For this purpose we vary a single parameter originally introduced by Faller and M{\"u}ller-Plathe, the chain stiffness. Examples include polystyrene, polyethylene, polypropylene, cis-polyisoprene, polydimethylsiloxane, polyethyleneoxide and styrene-butadiene rubber. We do this by matching the number of Kuhn segments per chain and the number of Kuhn segments per cubic Kuhn volume for the polymer species and for the Kremer-Grest model. We also derive mapping relations for converting KG model units back to physical units, in particular we obtain the entanglement time for the KG model as function of stiffness allowing for a time mapping. To test these relations, we generate large equilibrated well entangled polymer melts, and measure the entanglement moduli using a static primitive-path analysis of the entangled melt structure as well as by simulations of step-strain deformation of the model melts. The obtained moduli for our model polymer melts are in good agreement with the experimentally expected moduli.}, language = {en} } @article{CheenakulaHoffstadtKrafftetal.2022, author = {Cheenakula, Dheeraja and Hoffstadt, Kevin and Krafft, Simone and Reinecke, Diana and Klose, Holger and Kuperjans, Isabel and Gr{\"o}mping, Markus}, title = {Anaerobic digestion of algal-bacterial biomass of an Algal Turf Scrubber system}, series = {Biomass Conversion and Biorefinery}, volume = {13}, journal = {Biomass Conversion and Biorefinery}, publisher = {Springer}, address = {Berlin}, issn = {2190-6823}, doi = {10.1007/s13399-022-03236-z}, pages = {15 Seiten}, year = {2022}, abstract = {This study investigated the anaerobic digestion of an algal-bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal-bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4\%) and a mixture of manure and maize silage (107.4\%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6\%) and percolated green waste (43.5\%) inocula. To further evaluate the potential of algal-bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7-12.5 MWh a-1) can be gained through the addition of algal-bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.}, language = {en} } @article{MonakhovaDiehl2022, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Nuclear magnetic resonance spectroscopy as an elegant tool for a complete quality control of crude heparin material}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {219}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114915}, publisher = {Elsevier}, address = {New York, NY}, issn = {0731-7085}, doi = {10.1016/j.jpba.2022.114915}, year = {2022}, abstract = {Nuclear magnetic resonance (NMR) spectrometric methods for the quantitative analysis of pure heparin in crude heparin is proposed. For quantification, a two-step routine was developed using a USP heparin reference sample for calibration and benzoic acid as an internal standard. The method was successfully validated for its accuracy, reproducibility, and precision. The methodology was used to analyze 20 authentic porcine heparinoid samples having heparin content between 4.25 w/w \% and 64.4 w/w \%. The characterization of crude heparin products was further extended to a simultaneous analysis of these common ions: sodium, calcium, acetate and chloride. A significant, linear dependence was found between anticoagulant activity and assayed heparin content for thirteen heparinoids samples, for which reference data were available. A Diffused-ordered NMR experiment (DOSY) can be used for qualitative analysis of specific glycosaminoglycans (GAGs) in heparinoid matrices and, potentially, for quantitative prediction of molecular weight of GAGs. NMR spectrometry therefore represents a unique analytical method suitable for the simultaneous quantitative control of organic and inorganic composition of crude heparin samples (especially heparin content) as well as an estimation of other physical and quality parameters (molecular weight, animal origin and activity).}, language = {en} } @article{FalkenbergRahbaFischeretal.2022, author = {Falkenberg, Fabian and Rahba, Jade and Fischer, David and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {Biochemical characterization of a novel oxidatively stable, halotolerant, and high-alkaline subtilisin from Alkalihalobacillus okhensis Kh10-101T}, series = {FEBS Open Bio}, volume = {12}, journal = {FEBS Open Bio}, number = {10}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {2211-5463}, doi = {10.1002/2211-5463.13457}, pages = {1729 -- 1746}, year = {2022}, abstract = {Halophilic and halotolerant microorganisms represent a promising source of salt-tolerant enzymes suitable for various biotechnological applications where high salt concentrations would otherwise limit enzymatic activity. Considering the current growing enzyme market and the need for more efficient and new biocatalysts, the present study aimed at the characterization of a high-alkaline subtilisin from Alkalihalobacillus okhensis Kh10-101T. The protease gene was cloned and expressed in Bacillus subtilis DB104. The recombinant protease SPAO with 269 amino acids belongs to the subfamily of high-alkaline subtilisins. The biochemical characteristics of purified SPAO were analyzed in comparison with subtilisin Carlsberg, Savinase, and BPN'. SPAO, a monomer with a molecular mass of 27.1 kDa, was active over a wide range of pH 6.0-12.0 and temperature 20-80 °C, optimally at pH 9.0-9.5 and 55 °C. The protease is highly oxidatively stable to hydrogen peroxide and retained 58\% of residual activity when incubated at 10 °C with 5\% (v/v) H2O2 for 1 h while stimulated at 1\% (v/v) H2O2. Furthermore, SPAO was very stable and active at NaCl concentrations up to 5.0 m. This study demonstrates the potential of SPAO for biotechnological applications in the future.}, language = {en} } @article{FalkenbergBottBongaertsetal.2022, author = {Falkenberg, Fabian and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {Phylogenetic survey of the subtilase family and a data-mining-based search for new subtilisins from Bacillaceae}, series = {Frontiers in Microbiology}, volume = {2022}, journal = {Frontiers in Microbiology}, number = {13}, publisher = {Frontiers}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2022.1017978}, pages = {Artikel 13:1017978}, year = {2022}, abstract = {The subtilase family (S8), a member of the clan SB of serine proteases are ubiquitous in all kingdoms of life and fulfil different physiological functions. Subtilases are divided in several groups and especially subtilisins are of interest as they are used in various industrial sectors. Therefore, we searched for new subtilisin sequences of the family Bacillaceae using a data mining approach. The obtained 1,400 sequences were phylogenetically classified in the context of the subtilase family. This required an updated comprehensive overview of the different groups within this family. To fill this gap, we conducted a phylogenetic survey of the S8 family with characterised holotypes derived from the MEROPS database. The analysis revealed the presence of eight previously uncharacterised groups and 13 subgroups within the S8 family. The sequences that emerged from the data mining with the set filter parameters were mainly assigned to the subtilisin subgroups of true subtilisins, high-alkaline subtilisins, and phylogenetically intermediate subtilisins and represent an excellent source for new subtilisin candidates.}, language = {en} } @article{HaegerBongaertsSiegert2022, author = {Haeger, Gerrit and Bongaerts, Johannes and Siegert, Petra}, title = {A convenient ninhydrin assay in 96-well format for amino acid-releasing enzymes using an air-stable reagent}, series = {Analytical Biochemistry}, journal = {Analytical Biochemistry}, number = {624}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1096-0309}, doi = {10.1016/j.ab.2022.114819}, pages = {Artikel 114819}, year = {2022}, abstract = {An improved and convenient ninhydrin assay for aminoacylase activity measurements was developed using the commercial EZ Nin™ reagent. Alternative reagents from literature were also evaluated and compared. The addition of DMSO to the reagent enhanced the solubility of Ruhemann's purple (RP). Furthermore, we found that the use of a basic, aqueous buffer enhances stability of RP. An acidic protocol for the quantification of lysine was developed by addition of glacial acetic acid. The assay allows for parallel processing in a 96-well format with measurements microtiter plates.}, language = {en} } @article{WeldenSeverinsPoghossianetal.2022, author = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Bongaerts, Johannes and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor}, series = {Chemosensors}, volume = {10}, journal = {Chemosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2227-9040}, doi = {10.3390/chemosensors10060218}, pages = {Artikel 218}, year = {2022}, abstract = {Acetoin and diacetyl have a major impact on the flavor of alcoholic beverages such as wine or beer. Therefore, their measurement is important during the fermentation process. Until now, gas chromatographic techniques have typically been applied; however, these require expensive laboratory equipment and trained staff, and do not allow for online monitoring. In this work, a capacitive electrolyte-insulator-semiconductor sensor modified with tobacco mosaic virus (TMV) particles as enzyme nanocarriers for the detection of acetoin and diacetyl is presented. The enzyme acetoin reductase from Alkalihalobacillus clausii DSM 8716ᵀ is immobilized via biotin-streptavidin affinity, binding to the surface of the TMV particles. The TMV-assisted biosensor is electrochemically characterized by means of leakage-current, capacitance-voltage, and constant capacitance measurements. In this paper, the novel biosensor is studied regarding its sensitivity and long-term stability in buffer solution. Moreover, the TMV-assisted capacitive field-effect sensor is applied for the detection of diacetyl for the first time. The measurement of acetoin and diacetyl with the same sensor setup is demonstrated. Finally, the successive detection of acetoin and diacetyl in buffer and in diluted beer is studied by tuning the sensitivity of the biosensor using the pH value of the measurement solution.}, language = {en} } @article{OjovanSteinmetz2022, author = {Ojovan, Michael I. and Steinmetz, Hans-J{\"u}rgen}, title = {Approaches to Disposal of Nuclear Waste}, series = {Energies}, volume = {15}, journal = {Energies}, number = {20}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en15207804}, pages = {Artikel 7804}, year = {2022}, abstract = {We present a concise mini overview on the approaches to the disposal of nuclear waste currently used or deployed. The disposal of nuclear waste is the end point of nuclear waste management (NWM) activities and is the emplacement of waste in an appropriate facility without the intention to retrieve it. The IAEA has developed an internationally accepted classification scheme based on the end points of NWM, which is used as guidance. Retention times needed for safe isolation of waste radionuclides are estimated based on the radiotoxicity of nuclear waste. Disposal facilities usually rely on a multi-barrier defence system to isolate the waste from the biosphere, which comprises the natural geological barrier and the engineered barrier system. Disposal facilities could be of a trench type, vaults, tunnels, shafts, boreholes, or mined repositories. A graded approach relates the depth of the disposal facilities' location with the level of hazard. Disposal practices demonstrate the reliability of nuclear waste disposal with minimal expected impacts on the environment and humans.}, language = {en} } @article{ZhantlessovaSavitskayaKistaubayevaetal.2022, author = {Zhantlessova, Sirina and Savitskaya, Irina and Kistaubayeva, Aida and Ignatova, Ludmila and Talipova, Aizhan and Pogrebnjak, Alexander and Digel, Ilya}, title = {Advanced "Green" prebiotic composite of bacterial cellulose/pullulan based on synthetic biology-powered microbial coculture strategy}, series = {Polymers}, volume = {14}, journal = {Polymers}, number = {15}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {10.3390/polym14153224}, pages = {Artikel 3224}, year = {2022}, abstract = {Bacterial cellulose (BC) is a biopolymer produced by different microorganisms, but in biotechnological practice, Komagataeibacter xylinus is used. The micro- and nanofibrillar structure of BC, which forms many different-sized pores, creates prerequisites for the introduction of other polymers into it, including those synthesized by other microorganisms. The study aims to develop a cocultivation system of BC and prebiotic producers to obtain BC-based composite material with prebiotic activity. In this study, pullulan (PUL) was found to stimulate the growth of the probiotic strain Lactobacillus rhamnosus GG better than the other microbial polysaccharides gellan and xanthan. BC/PUL biocomposite with prebiotic properties was obtained by cocultivation of Komagataeibacter xylinus and Aureobasidium pullulans, BC and PUL producers respectively, on molasses medium. The inclusion of PUL in BC is proved gravimetrically by scanning electron microscopy and by Fourier transformed infrared spectroscopy. Cocultivation demonstrated a composite effect on the aggregation and binding of BC fibers, which led to a significant improvement in mechanical properties. The developed approach for "grafting" of prebiotic activity on BC allows preparation of environmentally friendly composites of better quality.}, language = {en} } @article{WeldenPoghossianVahidpouretal.2022, author = {Welden, Melanie and Poghossian, Arshak and Vahidpour, Farnoosh and Wendlandt, Tim and Keusgen, Michael and Wege, Christina and Sch{\"o}ning, Michael Josef}, title = {Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers}, series = {Biosensors}, volume = {12}, journal = {Biosensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios12010043}, pages = {Artikel 43}, year = {2022}, abstract = {Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1-3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate.}, language = {en} } @article{WeldenJablonskiWegeetal.2021, author = {Welden, Rene and Jablonski, Melanie and Wege, Christina and Keusgen, Michael and Wagner, Patrick Hermann and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase}, series = {Biosensors}, volume = {11}, journal = {Biosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios11060171}, pages = {Artikel 171}, year = {2021}, abstract = {The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte's pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.}, language = {en} } @article{HafidiElHatkaSchmitzetal.2024, author = {Hafidi, Youssef and El Hatka, Hicham and Schmitz, Dominik and Krauss, Manuel and Pettrak, J{\"u}rgen and Biel, Markus and Ittobane, Najim}, title = {Sustainable soil additives for water and micronutrient supply: swelling and chelating properties of polyaspartic acid hydrogels utilizing newly developed crosslinkers}, series = {Gels}, volume = {10}, journal = {Gels}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2310-2861}, doi = {10.3390/gels10030170}, pages = {Artikel 170}, year = {2024}, abstract = {Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10\% vs. 20\%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.}, language = {en} } @article{CapitainWagnerHummeletal.2021, author = {Capitain, Charlotte and Wagner, Sebastian and Hummel, Joana and Tippk{\"o}tter, Nils}, title = {Investigation of C-N Formation Between Catechols and Chitosan for the Formation of a Strong, Novel Adhesive Mimicking Mussel Adhesion}, series = {Waste and Biomass Valorization}, volume = {12}, journal = {Waste and Biomass Valorization}, publisher = {Springer Nature}, address = {Cham}, issn = {1877-265X}, doi = {10.1007/s12649-020-01110-5}, pages = {1761 -- 1779}, year = {2021}, language = {en} } @misc{StadtmuellerTippkoetterUlber2015, author = {Stadtm{\"u}ller, Ralf and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Method for production of single-stranded macronucleotides}, year = {2015}, abstract = {The invention relates to a method for production of single-stranded macronucleotides by amplifying and ligating an extended monomeric single-stranded target nucleic acid sequence (targetss) into a repetitive cluster of double-stranded target nucleic acid sequences (targetds), and subsequently cloning the construct into a vector (aptagene vector). The aptagene vector is transformed into host cells for replication of the aptagene and isolated in order to optain single-stranded target sequences (targetss). The invention also relates to single-stranded nucleic acids, produced by a method of the invention.}, language = {en} } @article{MonakhovaDiehl2021, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Novel approach of qNMR workflow by standardization using 2H integral: Application to any intrinsic calibration standard}, series = {Talanta}, volume = {222}, journal = {Talanta}, number = {Article number: 121504}, publisher = {Elsevier}, isbn = {0039-9140}, doi = {10.1016/j.talanta.2020.121504}, year = {2021}, abstract = {Quantitative nuclear magnetic resonance (qNMR) is routinely performed by the internal or external standardization. The manuscript describes a simple alternative to these common workflows by using NMR signal of another active nuclei of calibration compound. For example, for any arbitrary compound quantification by NMR can be based on the use of an indirect concentration referencing that relies on a solvent having both 1H and 2H signals. To perform high-quality quantification, the deuteration level of the utilized deuterated solvent has to be estimated. In this contribution the new method was applied to the determination of deuteration levels in different deuterated solvents (MeOD, ACN, CDCl3, acetone, benzene, DMSO-d6). Isopropanol-d6, which contains a defined number of deuterons and protons, was used for standardization. Validation characteristics (precision, accuracy, robustness) were calculated and the results showed that the method can be used in routine practice. Uncertainty budget was also evaluated. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and can be applied in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).}, language = {en} }