@article{MonakhovaDiehl2022, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Multinuclear NMR screening of pharmaceuticals using standardization by 2H integral of a deuterated solvent}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {209}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114530}, publisher = {Elsevier}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2021.114530}, year = {2022}, abstract = {NMR standardization approach that uses the 2H integral of deuterated solvent for quantitative multinuclear analysis of pharmaceuticals is described. As a proof of principle, the existing NMR procedure for the analysis of heparin products according to US Pharmacopeia monograph is extended to the determination of Na+ and Cl- content in this matrix. Quantification is performed based on the ratio of a 23Na (35Cl) NMR integral and 2H NMR signal of deuterated solvent, D2O, acquired using the specific spectrometer hardware. As an alternative, the possibility of 133Cs standardization using the addition of Cs2CO3 stock solution is shown. Validation characteristics (linearity, repeatability, sensitivity) are evaluated. A holistic NMR profiling of heparin products can now also be used for the quantitative determination of inorganic compounds in a single analytical run using a single sample. In general, the new standardization methodology provides an appealing alternative for the NMR screening of inorganic and organic components in pharmaceutical products.}, language = {en} } @article{BlockMayWetzeletal.2023, author = {Block, Franziska and May, Alexander and Wetzel, Katharina and Adels, Klaudia and Elbers, Gereon and Schulze, Margit and Monakhova, Yulia}, title = {What is the best spectroscopic method for simultaneous analysis of organic acids and (poly)saccharides in biological matrices: Example of Aloe vera extracts?}, series = {Talanta Open}, volume = {7}, journal = {Talanta Open}, number = {Art. No. 100220}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2666-8319}, doi = {10.1016/j.talo.2023.100220}, pages = {1 -- 9}, year = {2023}, abstract = {Several species of (poly)saccharides and organic acids can be found often simultaneously in various biological matrices, e.g., fruits, plant materials, and biological fluids. The analysis of such matrices sometimes represents a challenging task. Using Aloe vera (A. vera) plant materials as an example, the performance of several spectro-scopic methods (80 MHz benchtop NMR, NIR, ATR-FTIR and UV-vis) for the simultaneous analysis of quality parameters of this plant material was compared. The determined parameters include (poly)saccharides such as aloverose, fructose and glucose as well as organic acids (malic, lactic, citric, isocitric, acetic, fumaric, benzoic and sorbic acids). 500 MHz NMR and high-performance liquid chromatography (HPLC) were used as the reference methods. UV-vis data can be used only for identification of added preservatives (benzoic and sorbic acids) and drying agent (maltodextrin) and semiquantitative analysis of malic acid. NIR and MIR spectroscopies combined with multivariate regression can deliver more informative overview of A. vera extracts being able to additionally quantify glucose, aloverose, citric, isocitric, malic, lactic acids and fructose. Low-field NMR measurements can be used for the quantification of aloverose, glucose, malic, lactic, acetic, and benzoic acids. The benchtop NMR method was successfully validated in terms of robustness, stability, precision, reproducibility and limit of detection (LOD) and quantification (LOQ), respectively. All spectroscopic techniques are useful for the screening of (poly)saccharides and organic acids in plant extracts and should be applied according to its availability as well as information and confidence required for the specific analytical goal. Benchtop NMR spectroscopy seems to be the most feasible solution for quality control of A. vera products.}, language = {en} } @article{MolinnusJanusFangetal.2022, author = {Molinnus, Denise and Janus, Kevin Alexander and Fang, Anyelina C. and Drinic, Aleksander and Achtsnicht, Stefan and K{\"o}pf, Marius and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Thick-film carbon electrode deposited onto a biodegradable fibroin substrate for biosensing applications}, series = {Physica status solidi (a)}, volume = {219}, journal = {Physica status solidi (a)}, number = {23}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.202200100}, pages = {1 -- 9}, year = {2022}, abstract = {This study addresses a proof-of-concept experiment with a biocompatible screen-printed carbon electrode deposited onto a biocompatible and biodegradable substrate, which is made of fibroin, a protein derived from silk of the Bombyx mori silkworm. To demonstrate the sensor performance, the carbon electrode is functionalized as a glucose biosensor with the enzyme glucose oxidase and encapsulated with a silicone rubber to ensure biocompatibility of the contact wires. The carbon electrode is fabricated by means of thick-film technology including a curing step to solidify the carbon paste. The influence of the curing temperature and curing time on the electrode morphology is analyzed via scanning electron microscopy. The electrochemical characterization of the glucose biosensor is performed by amperometric/voltammetric measurements of different glucose concentrations in phosphate buffer. Herein, systematic studies at applied potentials from 500 to 1200 mV to the carbon working electrode (vs the Ag/AgCl reference electrode) allow to determine the optimal working potential. Additionally, the influence of the curing parameters on the glucose sensitivity is examined over a time period of up to 361 days. The sensor shows a negligible cross-sensitivity toward ascorbic acid, noradrenaline, and adrenaline. The developed biocompatible biosensor is highly promising for future in vivo and epidermal applications.}, language = {en} } @article{OezsoyluKizildagSchoeningetal.2020, author = {{\"O}zsoylu, Dua and Kizildag, Sefa and Sch{\"o}ning, Michael Josef and Wagner, Torsten}, title = {Differential chemical imaging of extracellular acidification within microfluidic channels using a plasma-functionalized light-addressable potentiometric sensor (LAPS)}, series = {Physics in Medicine}, volume = {10}, journal = {Physics in Medicine}, number = {100030}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-4510}, doi = {10.1016/j.phmed.2020.100030}, pages = {8}, year = {2020}, abstract = {Extracellular acidification is a basic indicator for alterations in two vital metabolic pathways: glycolysis and cellular respiration. Measuring these alterations by monitoring extracellular acidification using cell-based biosensors such as LAPS plays an important role in studying these pathways whose disorders are associated with numerous diseases including cancer. However, the surface of the biosensors must be specially tailored to ensure high cell compatibility so that cells can represent more in vivo-like behavior, which is critical to gain more realistic in vitro results from the analyses, e.g., drug discovery experiments. In this work, O2 plasma patterning on the LAPS surface is studied to enhance surface features of the sensor chip, e.g., wettability and biofunctionality. The surface treated with O2 plasma for 30 s exhibits enhanced cytocompatibility for adherent CHO-K1 cells, which promotes cell spreading and proliferation. The plasma-modified LAPS chip is then integrated into a microfluidic system, which provides two identical channels to facilitate differential measurements of the extracellular acidification of CHO-K1 cells. To the best of our knowledge, it is the first time that extracellular acidification within microfluidic channels is quantitatively visualized as differential (bio-)chemical images.}, language = {en} } @article{EngelmannPourshahidiShalabyetal.2022, author = {Engelmann, Ulrich M. and Pourshahidi, Mohammad Ali and Shalaby, Ahmed and Krause, Hans-Joachim}, title = {Probing particle size dependency of frequency mixing magnetic detection with dynamic relaxation simulation}, series = {Journal of Magnetism and Magnetic Materials}, volume = {563}, journal = {Journal of Magnetism and Magnetic Materials}, number = {In progress, Art. No. 169965}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-8853}, doi = {10.1016/j.jmmm.2022.169965}, year = {2022}, abstract = {Biomedical applications of magnetic nanoparticles (MNP) fundamentally rely on the particles' magnetic relaxation as a response to an alternating magnetic field. The magnetic relaxation complexly depends on the interplay of MNP magnetic and physical properties with the applied field parameters. It is commonly accepted that particle core size is a major contributor to signal generation in all the above applications, however, most MNP samples comprise broad distribution spanning nm and more. Therefore, precise knowledge of the exact contribution of individual core sizes to signal generation is desired for optimal MNP design generally for each application. Specifically, we present a magnetic relaxation simulation-driven analysis of experimental frequency mixing magnetic detection (FMMD) for biosensing to quantify the contributions of individual core size fractions towards signal generation. Applying our method to two different experimental MNP systems, we found the most dominant contributions from approx. 20 nm sized particles in the two independent MNP systems. Additional comparison between freely suspended and immobilized MNP also reveals insight in the MNP microstructure, allowing to use FMMD for MNP characterization, as well as to further fine-tune its applicability in biosensing.}, language = {en} } @article{AchtsnichtToedterNiehuesetal.2019, author = {Achtsnicht, Stefan and T{\"o}dter, Julia and Niehues, Julia and Tel{\"o}ken, Matthias and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim and Schr{\"o}per, Florian}, title = {3D printed modular immunofiltration columns for frequency mixing-based multiplex magnetic immunodetection}, series = {Sensors}, volume = {19}, journal = {Sensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s19010148}, pages = {15 Seiten}, year = {2019}, abstract = {For performing point-of-care molecular diagnostics, magnetic immunoassays constitute a promising alternative to established enzyme-linked immunosorbent assays (ELISA) because they are fast, robust and sensitive. Simultaneous detection of multiple biomolecular targets from one body fluid sample is desired. The aim of this work is to show that multiplex magnetic immunodetection based on magnetic frequency mixing by means of modular immunofiltration columns prepared for different targets is feasible. By calculations of the magnetic response signal, the required spacing between the modules was determined. Immunofiltration columns were manufactured by 3D printing and antibody immobilization was performed in a batch approach. It was shown experimentally that two different target molecules in a sample solution could be individually detected in a single assaying step with magnetic measurements of the corresponding immobilization filters. The arrangement order of the filters and of a negative control did not influence the results. Thus, a simple and reliable approach to multi-target magnetic immunodetection was demonstrated.}, language = {en} } @article{HeuermannSadeghfam2009, author = {Heuermann, Holger and Sadeghfam, Arash}, title = {Enhanced system architecture for rugged wide band data transmission / Sadeghfam, A. ; Heuermann, H.}, series = {European Radar Conference, 2009 : EuRAD 2009 ; Sept. 30 - Oct. 2 2009, Rome, Italy ; part of the European Microwave Week (EuMW) / sponsored by EuMA, European Microwave Association}, journal = {European Radar Conference, 2009 : EuRAD 2009 ; Sept. 30 - Oct. 2 2009, Rome, Italy ; part of the European Microwave Week (EuMW) / sponsored by EuMA, European Microwave Association}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-2-87487-014-9}, pages = {347 -- 350}, year = {2009}, language = {en} } @article{AdelsElbersDiehletal.2023, author = {Adels, Klaudia and Elbers, Gereon and Diehl, Bernd and Monakhova, Yulia}, title = {Multicomponent analysis of dietary supplements containing glucosamine and chondroitin: comparative low- and high-field NMR spectroscopic study}, series = {Analytical Sciences}, volume = {2023}, journal = {Analytical Sciences}, publisher = {Springer Verlag}, address = {Cham}, issn = {1348-2246 (Online)}, doi = {10.1007/s44211-023-00433-2}, pages = {13 Seiten}, year = {2023}, abstract = {With the prevalence of glucosamine- and chondroitin-containing dietary supplements for people with osteoarthritis in the marketplace, it is important to have an accurate and reproducible analytical method for the quantitation of these compounds in finished products. NMR spectroscopic method based both on low- (80 MHz) and high- (500-600 MHz) field NMR instrumentation was established, compared and validated for the determination of chondroitin sulfate and glucosamine in dietary supplements. The proposed method was applied for analysis of 20 different dietary supplements. In the majority of cases, quantification results obtained on the low-field NMR spectrometer are similar to those obtained with high-field 500-600 MHz NMR devices. Validation results in terms of accuracy, precision, reproducibility, limit of detection and recovery demonstrated that the developed method is fit for purpose for the marketed products. The NMR method was extended to the analysis of methylsulfonylmethane, adulterant maltodextrin, acetate and inorganic ions. Low-field NMR can be a quicker and cheaper alternative to more expensive high-field NMR measurements for quality control of the investigated dietary supplements. High-field NMR instrumentation can be more favorable for samples with complex composition due to better resolution, simultaneously giving the possibility of analysis of inorganic species such as potassium and chloride.}, language = {en} } @article{TrappLammersEngudaretal.2023, author = {Trapp, Svenja and Lammers, Tom and Engudar, Gokce and Hoehr, Cornelia and Denkova, Antonia G. and Paulßen, Elisabeth and de Kruijff, Robin M.}, title = {Membrane-based microfluidic solvent extraction of Ga-68 from aqueous Zn solutions: towards an automated cyclotron production loop}, series = {EJNMMI Radiopharmacy and Chemistry}, volume = {2023}, journal = {EJNMMI Radiopharmacy and Chemistry}, number = {8, Article number: 9}, publisher = {Springer Nature}, issn = {2365-421X}, doi = {10.1186/s41181-023-00195-2}, pages = {1 -- 14}, year = {2023}, language = {en} } @article{MonakhovaDiehl2021, author = {Monakhova, Yulia and Diehl, Bernd W. K.}, title = {A step towards optimization of the qNMR workflow: proficiency testing exercise at an GxP-accredited laboratory}, series = {Applied Magnetic Resonance}, volume = {52}, journal = {Applied Magnetic Resonance}, publisher = {Springer Nature}, address = {Wien}, issn = {1613-7507}, doi = {10.1007/s00723-021-01324-3}, pages = {581 -- 593}, year = {2021}, abstract = {Quantitative nuclear magnetic resonance (qNMR) is considered as a powerful tool for multicomponent mixture analysis as well as for the purity determination of single compounds. Special attention is currently paid to the training of operators and study directors involved in qNMR testing. To assure that only qualified personnel are used for sample preparation at our GxP-accredited laboratory, weighing test was proposed. Sixteen participants performed six-fold weighing of the binary mixture of dibutylated hydroxytoluene (BHT) and 1,2,4,5-tetrachloro-3-nitrobenzene (TCNB). To evaluate the quality of data analysis, all spectra were evaluated manually by a qNMR expert and using in-house developed automated routine. The results revealed that mean values are comparable and both evaluation approaches are free of systematic error. However, automated evaluation resulted in an approximately 20\% increase in precision. The same findings were revealed for qNMR analysis of 32 compounds used in pharmaceutical industry. Weighing test by six-fold determination in binary mixtures and automated qNMR methodology can be recommended as efficient tools for evaluating staff proficiency. The automated qNMR method significantly increases throughput and precision of qNMR for routine measurements and extends application scope of qNMR.}, language = {en} } @article{EngelmannShalabyShashaetal.2021, author = {Engelmann, Ulrich M. and Shalaby, Ahmed and Shasha, Carolyn and Krishnan, Kannan M. and Krause, Hans-Joachim}, title = {Comparative modeling of frequency mixing measurements of magnetic nanoparticles using micromagnetic simulations and Langevin theory}, series = {Nanomaterials}, volume = {11}, journal = {Nanomaterials}, number = {5}, publisher = {MDPI}, address = {Basel}, isbn = {2079-4991}, doi = {10.3390/nano11051257}, pages = {1 -- 16}, year = {2021}, abstract = {Dual frequency magnetic excitation of magnetic nanoparticles (MNP) enables enhanced biosensing applications. This was studied from an experimental and theoretical perspective: nonlinear sum-frequency components of MNP exposed to dual-frequency magnetic excitation were measured as a function of static magnetic offset field. The Langevin model in thermodynamic equilibrium was fitted to the experimental data to derive parameters of the lognormal core size distribution. These parameters were subsequently used as inputs for micromagnetic Monte-Carlo (MC)-simulations. From the hysteresis loops obtained from MC-simulations, sum-frequency components were numerically demodulated and compared with both experiment and Langevin model predictions. From the latter, we derived that approximately 90\% of the frequency mixing magnetic response signal is generated by the largest 10\% of MNP. We therefore suggest that small particles do not contribute to the frequency mixing signal, which is supported by MC-simulation results. Both theoretical approaches describe the experimental signal shapes well, but with notable differences between experiment and micromagnetic simulations. These deviations could result from Brownian relaxations which are, albeit experimentally inhibited, included in MC-simulation, or (yet unconsidered) cluster-effects of MNP, or inaccurately derived input for MC-simulations, because the largest particles dominate the experimental signal but concurrently do not fulfill the precondition of thermodynamic equilibrium required by Langevin theory.}, language = {en} } @article{AliaziziOezsoyluBakhshiSichanietal.2024, author = {Aliazizi, Fereshteh and {\"O}zsoylu, Dua and Bakhshi Sichani, Soroush and Khorshid, Mehran and Glorieux, Christ and Robbens, Johan and Sch{\"o}ning, Michael Josef and Wagner, Patrick}, title = {Development and Calibration of a Microfluidic, Chip-Based Sensor System for Monitoring the Physical Properties of Water Samples in Aquacultures}, series = {Micromachines}, volume = {15}, journal = {Micromachines}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2072-666X}, doi = {10.3390/mi15060755}, year = {2024}, abstract = {In this work, we present a compact, bifunctional chip-based sensor setup that measures the temperature and electrical conductivity of water samples, including specimens from rivers and channels, aquaculture, and the Atlantic Ocean. For conductivity measurements, we utilize the impedance amplitude recorded via interdigitated electrode structures at a single triggering frequency. The results are well in line with data obtained using a calibrated reference instrument. The new setup holds for conductivity values spanning almost two orders of magnitude (river versus ocean water) without the need for equivalent circuit modelling. Temperature measurements were performed in four-point geometry with an on-chip platinum RTD (resistance temperature detector) in the temperature range between 2 °C and 40 °C, showing no hysteresis effects between warming and cooling cycles. Although the meander was not shielded against the liquid, the temperature calibration provided equivalent results to low conductive Milli-Q and highly conductive ocean water. The sensor is therefore suitable for inline and online monitoring purposes in recirculating aquaculture systems.}, language = {en} } @article{Kurz2006, author = {Kurz, Melanie}, title = {Der Modell-Roller}, series = {Form : the making of design}, volume = {2006}, journal = {Form : the making of design}, number = {209}, isbn = {0015-7678}, pages = {64 -- 72}, year = {2006}, language = {de} } @article{ZhantlessovaSavitskayaKistaubayevaetal.2024, author = {Zhantlessova, Sirina and Savitskaya, Irina and Kistaubayeva, Aida and Ignatova, Ludmila and Talipova, Aizhan and Pogrebnjak, Alexander and Digel, Ilya}, title = {Correction: Zhantlessova et al. advanced "Green" prebiotic composite of bacterial cellulose/pullulan based on synthetic biology-powered microbial coculture strategy. Polymers 2022, 14, 3224}, series = {Polymers}, volume = {16}, journal = {Polymers}, number = {13}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {10.3390/polym16131802}, pages = {2 Seiten}, year = {2024}, language = {en} } @article{FalkenbergVossBottetal.2023, author = {Falkenberg, Fabian and Voß, Leonie and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {New robust subtilisins from halotolerant and halophilic Bacillaceae}, series = {Applied Microbiology and Biotechnology}, volume = {107}, journal = {Applied Microbiology and Biotechnology}, publisher = {Springer Nature}, address = {Berlin}, issn = {1432-0614}, doi = {10.1007/s00253-023-12553-w}, pages = {3939 -- 3954}, year = {2023}, abstract = {The aim of the present study was the characterisation of three true subtilisins and one phylogenetically intermediate subtilisin from halotolerant and halophilic microorganisms. Considering the currently growing enzyme market for efficient and novel biocatalysts, data mining is a promising source for novel, as yet uncharacterised enzymes, especially from halophilic or halotolerant Bacillaceae, which offer great potential to meet industrial needs. Both halophilic bacteria Pontibacillus marinus DSM 16465ᵀ and Alkalibacillus haloalkaliphilus DSM 5271ᵀ and both halotolerant bacteria Metabacillus indicus DSM 16189 and Litchfieldia alkalitelluris DSM 16976ᵀ served as a source for the four new subtilisins SPPM, SPAH, SPMI and SPLA. The protease genes were cloned and expressed in Bacillus subtilis DB104. Purification to apparent homogeneity was achieved by ethanol precipitation, desalting and ion-exchange chromatography. Enzyme activity could be observed between pH 5.0-12.0 with an optimum for SPPM, SPMI and SPLA around pH 9.0 and for SPAH at pH 10.0. The optimal temperature for SPMI and SPLA was 70 °C and for SPPM and SPAH 55 °C and 50 °C, respectively. All proteases showed high stability towards 5\% (w/v) SDS and were active even at NaCl concentrations of 5 M. The four proteases demonstrate potential for future biotechnological applications.}, language = {en} } @article{SaretzkiBergmannDahmannetal.2021, author = {Saretzki, Charlotte and Bergmann, Ole and Dahmann, Peter and Janser, Frank and Keimer, Jona and Machado, Patricia and Morrison, Audry and Page, Henry and Pluta, Emil and St{\"u}bing, Felix and K{\"u}pper, Thomas}, title = {Are small airplanes safe with regards to COVID-19 transmission?}, series = {Journal of Travel Medicine}, volume = {28}, journal = {Journal of Travel Medicine}, number = {7}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1708-8305}, doi = {10.1093/jtm/taab105}, year = {2021}, language = {en} } @article{HarrisKleefeld2022, author = {Harris, Isaac and Kleefeld, Andreas}, title = {Analysis and computation of the transmission eigenvalues with a conductive boundary condition}, series = {Applicable Analysis}, volume = {101}, journal = {Applicable Analysis}, number = {6}, publisher = {Taylor \& Francis}, address = {London}, issn = {1563-504X}, doi = {10.1080/00036811.2020.1789598}, pages = {1880 -- 1895}, year = {2022}, abstract = {We provide a new analytical and computational study of the transmission eigenvalues with a conductive boundary condition. These eigenvalues are derived from the scalar inverse scattering problem for an inhomogeneous material with a conductive boundary condition. The goal is to study how these eigenvalues depend on the material parameters in order to estimate the refractive index. The analytical questions we study are: deriving Faber-Krahn type lower bounds, the discreteness and limiting behavior of the transmission eigenvalues as the conductivity tends to infinity for a sign changing contrast. We also provide a numerical study of a new boundary integral equation for computing the eigenvalues. Lastly, using the limiting behavior we will numerically estimate the refractive index from the eigenvalues provided the conductivity is sufficiently large but unknown.}, language = {en} } @article{Baehr2012, author = {B{\"a}hr, Brigitte}, title = {[Gert Hoepner] im Interview zum Thema ; Verpackungspolitik - mehr als H{\"u}lle}, series = {Packaging journal : Technologie, Logistik, Marketing, Produkte}, journal = {Packaging journal : Technologie, Logistik, Marketing, Produkte}, number = {5}, publisher = {Ella Verlag}, address = {H{\"u}rth}, issn = {1610-0336}, pages = {78 -- 80}, year = {2012}, language = {de} } @article{Kuperjans1996, author = {Kuperjans, Isabel}, title = {Exergetische und exergo{\"o}konomische Analyse thermischer Prozesse}, series = {Arbeitsbericht / Institut f{\"u}r Wirtschaftswissenschaften, Rheinisch-Westf{\"a}lische Technische Hochschule Aachen}, journal = {Arbeitsbericht / Institut f{\"u}r Wirtschaftswissenschaften, Rheinisch-Westf{\"a}lische Technische Hochschule Aachen}, number = {06}, year = {1996}, language = {de} } @article{HaegerWirgesTanzmannetal.2023, author = {Haeger, Gerrit and Wirges, Jessika and Tanzmann, Nicole and Oyen, Sven and Jolmes, Tristan and Jaeger, Karl-Erich and Sch{\"o}rken, Ulrich and Bongaerts, Johannes and Siegert, Petra}, title = {Chaperone assisted recombinant expression of a mycobacterial aminoacylase in Vibrio natriegens and Escherichia coli capable of N-lauroyl-L-amino acid synthesis}, series = {Microbial Cell Factories}, journal = {Microbial Cell Factories}, number = {22}, publisher = {Springer Nature}, issn = {1475-2859}, doi = {10.1186/s12934-023-02079-1}, pages = {Article number: 77 (2023)}, year = {2023}, abstract = {Background Aminoacylases are highly promising enzymes for the green synthesis of acyl-amino acids, potentially replacing the environmentally harmful Schotten-Baumann reaction. Long-chain acyl-amino acids can serve as strong surfactants and emulsifiers, with application in cosmetic industries. Heterologous expression of these enzymes, however, is often hampered, limiting their use in industrial processes. Results We identified a novel mycobacterial aminoacylase gene from Mycolicibacterium smegmatis MKD 8, cloned and expressed it in Escherichia coli and Vibrio natriegens using the T7 overexpression system. The recombinant enzyme was prone to aggregate as inclusion bodies, and while V. natriegens Vmax™ could produce soluble aminoacylase upon induction with isopropyl β-d-1-thiogalactopyranoside (IPTG), E. coli BL21 (DE3) needed autoinduction with lactose to produce soluble recombinant protein. We successfully conducted a chaperone co-expression study in both organisms to further enhance aminoacylase production and found that overexpression of chaperones GroEL/S enhanced aminoacylase activity in the cell-free extract 1.8-fold in V. natriegens and E. coli. Eventually, E. coli ArcticExpress™ (DE3), which co-expresses cold-adapted chaperonins Cpn60/10 from Oleispira antarctica, cultivated at 12 °C, rendered the most suitable expression system for this aminoacylase and exhibited twice the aminoacylase activity in the cell-free extract compared to E. coli BL21 (DE3) with GroEL/S co-expression at 20 °C. The purified aminoacylase was characterized based on hydrolytic activities, being most stable and active at pH 7.0, with a maximum activity at 70 °C, and stability at 40 °C and pH 7.0 for 5 days. The aminoacylase strongly prefers short-chain acyl-amino acids with smaller, hydrophobic amino acid residues. Several long-chain amino acids were fairly accepted in hydrolysis as well, especially N-lauroyl-L-methionine. To initially evaluate the relevance of this aminoacylase for the synthesis of N-acyl-amino acids, we demonstrated that lauroyl-methionine can be synthesized from lauric acid and methionine in an aqueous system. Conclusion Our results suggest that the recombinant enzyme is well suited for synthesis reactions and will thus be further investigated.}, language = {en} } @article{ZhenLiangStaatetal.2024, author = {Zhen, Manghao and Liang, Yunpei and Staat, Manfred and Li, Quanqui and Li, Jianbo}, title = {Discontinuous fracture behaviors and constitutive model of sandstone specimens containing non-parallel prefabricated fissures under uniaxial compression}, series = {Theoretical and Applied Fracture Mechanics}, volume = {131}, journal = {Theoretical and Applied Fracture Mechanics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0167-8442}, doi = {10.1016/j.tafmec.2024.104373}, pages = {Artikel 104373}, year = {2024}, abstract = {The deformation and damage laws of non-homogeneous irregular structural planes in rocks are the basis for studying the stability of rock engineering. To investigate the damage characteristics of rock containing non-parallel fissures, uniaxial compression tests and numerical simulations were conducted on sandstone specimens containing three non-parallel fissures inclined at 0°, 45° and 90° in this study. The characteristics of crack initiation and crack evolution of fissures with different inclinations were analyzed. A constitutive model for the discontinuous fractures of fissured sandstone was proposed. The results show that the fracture behaviors of fissured sandstone specimens are discontinuous. The stress-strain curves are non-smooth and can be divided into nonlinear crack closure stage, linear elastic stage, plastic stage and brittle failure stage, of which the plastic stage contains discontinuous stress drops. During the uniaxial compression test, the middle or ends of 0° fissures were the first to crack compared to 45° and 90° fissures. The end with small distance between 0° and 45° fissures cracked first, and the end with large distance cracked later. After the final failure, 0° fissures in all specimens were fractured, while 45° and 90° fissures were not necessarily fractured. Numerical simulation results show that the concentration of compressive stress at the tips of 0°, 45° and 90° fissures, as well as the concentration of tensile stress on both sides, decreased with the increase of the inclination angle. A constitutive model for the discontinuous fractures of fissured sandstone specimens was derived by combining the logistic model and damage mechanic theory. This model can well describe the discontinuous drops of stress and agrees well with the whole processes of the stress-strain curves of the fissured sandstone specimens.}, language = {en} } @article{KeutmannStaatLaack2018, author = {Keutmann, Sabine and Staat, Manfred and Laack, Walter van}, title = {Untersuchung der thermischen Auswirkung von therapeutischem Ultraschall}, volume = {7}, number = {10}, publisher = {Deutscher {\"A}rzte-Verl.}, address = {K{\"o}ln}, issn = {2193-5793}, pages = {518 -- 522}, year = {2018}, abstract = {Zusammenfassung: In der Orthop{\"a}die z{\"a}hlt der therapeutische Ultraschall als Mittel zur Pr{\"a}vention und Therapiebegleitung. Er hat mechanische, thermische und physiko-chemische Auswirkungen auf den menschlichen K{\"o}rper. Um mehr Erkenntnisse {\"u}ber die thermischen Auswirkungen zu erlangen, wurden Versuche an einem Hydrogel-Phantom und an Probanden durchgef{\"u}hrt. Dabei entstand eine signifikante Erw{\"a}rmung des Gewebes, welche beim Probandenversuch an der Oberfl{\"a}che und beim Hydrogelversuch in der Tiefe gemessen wurde. Summary: In orthopaedics, therapeutic ultrasound is a tool of prevention and therapy support. It has mechanical, thermal and physico-chemical effects on the human body. Tests with a hydrogel phantom and with human probands have been performed in order to obtain more knowledge about their thermal effects. Both tests measured temperature increases in cell tissue, on the surface with the human proband test and in depth with the hydrogel phantom test.}, language = {de} } @article{DiktaReisselHarlass2016, author = {Dikta, Gerhard and Reißel, Martin and Harlaß, Carsten}, title = {Semi-parametric survival function estimators deduced from an identifying Volterra type integral equation}, series = {Journal of multivariate analysis}, journal = {Journal of multivariate analysis}, number = {147}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.jmva.2016.02.008}, pages = {273 -- 284}, year = {2016}, abstract = {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.}, language = {en} } @article{WingensMayPfaff2019, author = {Wingens, Niklas and May, J{\"o}rg and Pfaff, Raphael}, title = {Betrieblich-technische Innovationsans{\"a}tze zur Bremsprobe nach einer Prozess{\"a}nderung}, series = {Eisenbahntechnische Rundschau : ETR ; Zeitschrift f{\"u}r die gesamte Eisenbahntechnik}, journal = {Eisenbahntechnische Rundschau : ETR ; Zeitschrift f{\"u}r die gesamte Eisenbahntechnik}, number = {5}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2845}, pages = {5}, year = {2019}, language = {de} } @article{FunkeEschRoosen2022, author = {Funke, Harald and Esch, Thomas and Roosen, Petra}, title = {Antriebssystemanpassungen zur Verwendung von LPG als Flugkraftstoff}, series = {Motortechnische Zeitschrift (MTZ)}, volume = {2022}, journal = {Motortechnische Zeitschrift (MTZ)}, number = {83}, publisher = {Springer Nature}, address = {Basel}, doi = {10.1007/s35146-021-0778-2}, pages = {58 -- 62}, year = {2022}, abstract = {Auch in der allgemeinen Luftfahrt w{\"a}re es w{\"u}nschenswert, die bereits vorhandenen Verbrennungsmotoren mit weniger CO₂-tr{\"a}chtigen Kraftstoffen als dem heute weit verbreiteten Avgas 100LL betreiben zu k{\"o}nnen. Es ist anzunehmen, dass im Vergleich die unter Normalbedingungen gasf{\"o}rmigen Kraftstoffe CNG, LPG oder LNG deutlich weniger Emissionen produzieren. Erforderliche Antriebssystemanpassungen wurden im Rahmen eines Forschungsprojekts an der FH Aachen untersucht.}, language = {de} } @article{MichaelMayerWeberetal.2017, author = {Michael, Hackl and Mayer, Katharina and Weber, Mareike and Staat, Manfred and van Riet, Roger and Burkhart, Klau Josef and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {Plate osteosynthesis of proximal ulna fractures : a biomechanical micromotion analysis}, series = {The journal of hand surgery}, volume = {42}, journal = {The journal of hand surgery}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0363-5023}, doi = {10.1016/j.jhsa.2017.05.014}, pages = {834.e1 -- 834.e7}, year = {2017}, language = {en} } @article{SalpatiChuChenetal.2014, author = {Salpati, Laurent and Chu, Xiaoyan and Chen, Liangfu and Prasad, Bhagwat and Dallas, Shannon and Evers, Raymond and Mamaril-Fishman, Donna and Geier, Ethan G. and Kehler, Jonathan and Kunta, Jeevan and Mezler, Mario and Laplanche, Loic and Pang, Jodie and Soars, Matthew G. and Unadkat, Jashvant D. and van Waterschoot, Robert A.B. and Yabut, Jocelyn and Schinkel, Alfred H. and Scheer, Nico and Rode, Anja}, title = {Evaluation of organic anion transporting polypeptide 1B1 and 1B3 humanized mice as a translational model to study the pharmacokinetics of statins}, series = {Drug Metabolism and Disposition}, volume = {42}, journal = {Drug Metabolism and Disposition}, number = {8}, publisher = {ASPET}, address = {Bethesda, Md.}, issn = {1521-009X}, doi = {10.1124/dmd.114.057976}, pages = {1301 -- 1313}, year = {2014}, abstract = {Organic anion transporting polypeptide (Oatp) 1a/1b knockout and OATP1B1 and -1B3 humanized mouse models are promising tools for studying the roles of these transporters in drug disposition. Detailed characterization of these models will help to better understand their utility for predicting clinical outcomes. To advance this approach, we carried out a comprehensive analysis of these mouse lines by evaluating the compensatory changes in mRNA expression, quantifying the amounts of OATP1B1 and -1B3 protein by liquid chromatography-tandem mass spectrometry, and studying the active uptake in isolated hepatocytes and the pharmacokinetics of some prototypical substrates including statins. Major outcomes from these studies were 1) mostly moderate compensatory changes in only a few genes involved in drug metabolism and disposition, 2) a robust hepatic expression of OATP1B1 and -1B3 proteins in the respective humanized mouse models, and 3) functional activities of the human transporters in hepatocytes isolated from the humanized models with several substrates tested in vitro and with pravastatin in vivo. However, the expression of OATP1B1 and -1B3 in the humanized models did not significantly alter liver or plasma concentrations of rosuvastatin and pitavastatin compared with Oatp1a/1b knockout controls under the conditions used in our studies. Hence, although the humanized OATP1B1 and -1B3 mice showed in vitro and/or in vivo functional activity with some statins, further characterization of these models is required to define their potential use and limitations in the prediction of drug disposition and drug-drug interactions in humans.}, 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{ClausnitzerKleefeld2024, author = {Clausnitzer, Julian and Kleefeld, Andreas}, title = {A spectral Galerkin exponential Euler time-stepping scheme for parabolic SPDEs on two-dimensional domains with a C² boundary}, series = {Discrete and Continuous Dynamical Systems - Series B}, volume = {29}, journal = {Discrete and Continuous Dynamical Systems - Series B}, number = {4}, publisher = {AIMS}, address = {Springfield}, issn = {1531-3492}, doi = {10.3934/dcdsb.2023148}, pages = {1624 -- 1651}, year = {2024}, abstract = {We consider the numerical approximation of second-order semi-linear parabolic stochastic partial differential equations interpreted in the mild sense which we solve on general two-dimensional domains with a C² boundary with homogeneous Dirichlet boundary conditions. The equations are driven by Gaussian additive noise, and several Lipschitz-like conditions are imposed on the nonlinear function. We discretize in space with a spectral Galerkin method and in time using an explicit Euler-like scheme. For irregular shapes, the necessary Dirichlet eigenvalues and eigenfunctions are obtained from a boundary integral equation method. This yields a nonlinear eigenvalue problem, which is discretized using a boundary element collocation method and is solved with the Beyn contour integral algorithm. We present an error analysis as well as numerical results on an exemplary asymmetric shape, and point out limitations of the approach.}, language = {en} } @article{AbdelLatifPeekenBenner1985, author = {Abdel-Latif, Lotfie Ahmed and Peeken, Heinz and Benner, Joachim}, title = {Термогидродинамический расчет упорных подшипников с круговыми подушками на масляной пленке, содержащей пузырьки газа}, series = {Проблемы трения и смазки}, volume = {107}, journal = {Проблемы трения и смазки}, number = {4}, pages = {94 -- 102}, year = {1985}, language = {ru} } @article{Finkenberger2022, author = {Finkenberger, Isabel Maria}, title = {Strukturwandel als transformative Wende}, series = {disP: The Planning Review}, volume = {58}, journal = {disP: The Planning Review}, number = {3}, publisher = {Taylor \& Francis}, address = {Abingdon}, issn = {0251-3625}, doi = {10.1080/02513625.2022.2158603}, pages = {86 -- 94}, year = {2022}, language = {de} } @article{MartinVaqueroKleefeld2020, author = {Mart{\´i}n-Vaquero, J. and Kleefeld, Andreas}, title = {Solving nonlinear parabolic PDEs in several dimensions: Parallelized ESERK codes}, series = {Journal of Computational Physics}, journal = {Journal of Computational Physics}, number = {423}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9991}, doi = {10.1016/j.jcp.2020.109771}, year = {2020}, abstract = {There is a very large number of very important situations which can be modeled with nonlinear parabolic partial differential equations (PDEs) in several dimensions. In general, these PDEs can be solved by discretizing in the spatial variables and transforming them into huge systems of ordinary differential equations (ODEs), which are very stiff. Therefore, standard explicit methods require a large number of iterations to solve stiff problems. But implicit schemes are computationally very expensive when solving huge systems of nonlinear ODEs. Several families of Extrapolated Stabilized Explicit Runge-Kutta schemes (ESERK) with different order of accuracy (3 to 6) are derived and analyzed in this work. They are explicit methods, with stability regions extended, along the negative real semi-axis, quadratically with respect to the number of stages s, hence they can be considered to solve stiff problems much faster than traditional explicit schemes. Additionally, they allow the adaptation of the step length easily with a very small cost. Two new families of ESERK schemes (ESERK3 and ESERK6) are derived, and analyzed, in this work. Each family has more than 50 new schemes, with up to 84.000 stages in the case of ESERK6. For the first time, we also parallelized all these new variable step length and variable number of stages algorithms (ESERK3, ESERK4, ESERK5, and ESERK6). These parallelized strategies allow to decrease times significantly, as it is discussed and also shown numerically in two problems. Thus, the new codes provide very good results compared to other well-known ODE solvers. Finally, a new strategy is proposed to increase the efficiency of these schemes, and it is discussed the idea of combining ESERK families in one code, because typically, stiff problems have different zones and according to them and the requested tolerance the optimum order of convergence is different.}, language = {en} } @article{FingerBraunBil2018, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Impact of electric propulsion technology and mission requirements on the performance of VTOL UAVs}, series = {CEAS Aeronautical Journal}, volume = {10}, journal = {CEAS Aeronautical Journal}, number = {3}, publisher = {Springer}, issn = {1869-5582 print}, doi = {10.1007/s13272-018-0352-x}, pages = {843}, year = {2018}, abstract = {One of the engineering challenges in aviation is the design of transitioning vertical take-off and landing (VTOL) aircraft. Thrust-borne flight implies a higher mass fraction of the propulsion system, as well as much increased energy consumption in the take-off and landing phases. This mass increase is typically higher for aircraft with a separate lift propulsion system than for aircraft that use the cruise propulsion system to support a dedicated lift system. However, for a cost-benefit trade study, it is necessary to quantify the impact the VTOL requirement and propulsion configuration has on aircraft mass and size. For this reason, sizing studies are conducted. This paper explores the impact of considering a supplemental electric propulsion system for achieving hovering flight. Key variables in this study, apart from the lift system configuration, are the rotor disk loading and hover flight time, as well as the electrical systems technology level for both batteries and motors. Payload and endurance are typically used as the measures of merit for unmanned aircraft that carry electro-optical sensors, and therefore the analysis focuses on these particular parameters.}, language = {en} } @article{LempiaeinenCouttetBolognanietal.2012, author = {Lempi{\"a}inen, Harri and Couttet, Philippe and Bolognani, Federico and M{\"u}ller, Arne and Dubost, Val{\´e}rie and Luisier, Rapha{\"e}lle and Rio-Espinola, Alberto del and Vitry, Veronique and Unterberger, Elif B. and Thomson, John P. and Treindl, Fridolin and Metzger, Ute and Wrzodek, Clemens and Hahne, Florian and Zollinger, Tulipan and Brasa, Sarah and Kalteis, Magdalena and Marcellin, Magali and Giudicelli, Fanny and Braeuning, Albert and Morawiec, Laurent and Zamurovic, Natasa and L{\"a}ngle, Ulrich and Scheer, Nico and Sch{\"u}beler, Dirk and Goodman, Jay and Chibout, Salah-Dine and Marlowe, Jennifer and Theil, Dietlinde and Heard, David J. and Grenet, Olivier and Zell, Andreas and Templin, Markus F. and Meehan, Richard R. and Wolf, Roland C. and Elcombe, Clifford R. and Schwarz, Michael and Moulin, Pierre and Terranova, R{\´e}mi and Moggs, Jonathan G.}, title = {Identification of Dlk1-Dio3 imprinted gene cluster non-coding RNAs as novel candidate biomarkers for liver tumor promotion}, series = {Toxicological Sciences}, volume = {131}, journal = {Toxicological Sciences}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1094-2025}, doi = {10.1093/toxsci/kfs303}, pages = {375 -- 386}, year = {2012}, abstract = {The molecular events during nongenotoxic carcinogenesis and their temporal order are poorly understood but thought to include long-lasting perturbations of gene expression. Here, we have investigated the temporal sequence of molecular and pathological perturbations at early stages of phenobarbital (PB) mediated liver tumor promotion in vivo. Molecular profiling (mRNA, microRNA [miRNA], DNA methylation, and proteins) of mouse liver during 13 weeks of PB treatment revealed progressive increases in hepatic expression of long noncoding RNAs and miRNAs originating from the Dlk1-Dio3 imprinted gene cluster, a locus that has recently been associated with stem cell pluripotency in mice and various neoplasms in humans. PB induction of the Dlk1-Dio3 cluster noncoding RNA (ncRNA) Meg3 was localized to glutamine synthetase-positive hypertrophic perivenous hepatocytes, sug- gesting a role for β-catenin signaling in the dysregulation of Dlk1-Dio3 ncRNAs. The carcinogenic relevance of Dlk1-Dio3 locus ncRNA induction was further supported by in vivo genetic dependence on constitutive androstane receptor and β-catenin pathways. Our data identify Dlk1-Dio3 ncRNAs as novel candidate early biomarkers for mouse liver tumor promotion and provide new opportunities for assessing the carcinogenic potential of novel compounds.}, language = {en} } @article{RhodenBallGrajewskietal.2023, author = {Rhoden, Imke and Ball, Christopher Stephen and Grajewski, Matthias and Kuckshinrich, Wilhelm}, title = {Reverse engineering of stakeholder preferences - A multi-criteria assessment of the German passenger car sector}, series = {Renewable and Sustainable Energy Reviews}, volume = {181}, journal = {Renewable and Sustainable Energy Reviews}, number = {July 2023}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1364-0321}, doi = {10.1016/j.rser.2023.113352}, pages = {Article number: 113352}, year = {2023}, abstract = {Germany is a frontrunner in setting frameworks for the transition to a low-carbon system. The mobility sector plays a significant role in this shift, affecting different people and groups on multiple levels. Without acceptance from these stakeholders, emission targets are out of reach. This research analyzes how the heterogeneous preferences of various stakeholders align with the transformation of the mobility sector, looking at the extent to which the German transformation paths are supported and where stakeholders are located. Under the research objective of comparing stakeholders' preferences to identify which car segments require additional support for a successful climate transition, a status quo of stakeholders and car performance criteria is the foundation for the analysis. Stakeholders' hidden preferences hinder the derivation of criteria weightings from stakeholders; therefore, a ranking from observed preferences is used. This study's inverse multi-criteria decision analysis means that weightings can be predicted and used together with a recalibrated performance matrix to explore future preferences toward car segments. Results show that stakeholders prefer medium-sized cars, with the trend pointing towards the increased potential for alternative propulsion technologies and electrified vehicles. These insights can guide the improved targeting of policy supporting the energy and mobility transformation. Additionally, the method proposed in this work can fully handle subjective approaches while incorporating a priori information. A software implementation of the proposed method completes this work and is made publicly available.}, language = {en} } @article{KleefeldZimmermann2022, author = {Kleefeld, Andreas and Zimmermann, M.}, title = {Computing Elastic Interior Transmission Eigenvalues}, series = {Integral Methods in Science and Engineering}, journal = {Integral Methods in Science and Engineering}, editor = {Constanda, Christian and Bodmann, Bardo E.J. and Harris, Paul J.}, publisher = {Birkh{\"a}user}, address = {Cham}, isbn = {978-3-031-07171-3}, doi = {10.1007/978-3-031-07171-3_10}, pages = {139 -- 155}, year = {2022}, abstract = {An alternative method is presented to numerically compute interior elastic transmission eigenvalues for various domains in two dimensions. This is achieved by discretizing the resulting system of boundary integral equations in combination with a nonlinear eigenvalue solver. Numerical results are given to show that this new approach can provide better results than the finite element method when dealing with general domains.}, language = {en} } @article{PourshahidiAchtsnichtOffenhaeusseretal.2022, author = {Pourshahidi, Ali Mohammad and Achtsnicht, Stefan and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim}, title = {Frequency Mixing Magnetic Detection Setup Employing Permanent Ring Magnets as a Static Offset Field Source}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {22}, editor = {Offenh{\"a}usser, Andreas}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22228776}, pages = {12 Seiten}, year = {2022}, abstract = {Frequency mixing magnetic detection (FMMD) has been explored for its applications in fields of magnetic biosensing, multiplex detection of magnetic nanoparticles (MNP) and the determination of core size distribution of MNP samples. Such applications rely on the application of a static offset magnetic field, which is generated traditionally with an electromagnet. Such a setup requires a current source, as well as passive or active cooling strategies, which directly sets a limitation based on the portability aspect that is desired for point of care (POC) monitoring applications. In this work, a measurement head is introduced that involves the utilization of two ring-shaped permanent magnets to generate a static offset magnetic field. A steel cylinder in the ring bores homogenizes the field. By variation of the distance between the ring magnets and of the thickness of the steel cylinder, the magnitude of the magnetic field at the sample position can be adjusted. Furthermore, the measurement setup is compared to the electromagnet offset module based on measured signals and temperature behavior.}, language = {en} } @article{RoethenbacherCesariDoppleretal.2022, author = {R{\"o}thenbacher, Annika and Cesari, Matteo and Doppler, Christopher E.J. and Okkels, Niels and Willemsen, Nele and Sembowski, Nora and Seger, Aline and Lindner, Marie and Brune, Corinna and Stefani, Ambra and H{\"o}gl, Birgit and Bialonski, Stephan and Borghammer, Per and Fink, Gereon R. and Schober, Martin and Sommerauer, Michael}, title = {RBDtector: an open-source software to detect REM sleep without atonia according to visual scoring criteria}, series = {Scientific Reports}, volume = {12}, journal = {Scientific Reports}, number = {Article number: 20886}, publisher = {Springer Nature}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-022-25163-9}, pages = {1 -- 14}, year = {2022}, abstract = {REM sleep without atonia (RSWA) is a key feature for the diagnosis of rapid eye movement (REM) sleep behaviour disorder (RBD). We introduce RBDtector, a novel open-source software to score RSWA according to established SINBAR visual scoring criteria. We assessed muscle activity of the mentalis, flexor digitorum superficialis (FDS), and anterior tibialis (AT) muscles. RSWA was scored manually as tonic, phasic, and any activity by human scorers as well as using RBDtector in 20 subjects. Subsequently, 174 subjects (72 without RBD and 102 with RBD) were analysed with RBDtector to show the algorithm's applicability. We additionally compared RBDtector estimates to a previously published dataset. RBDtector showed robust conformity with human scorings. The highest congruency was achieved for phasic and any activity of the FDS. Combining mentalis any and FDS any, RBDtector identified RBD subjects with 100\% specificity and 96\% sensitivity applying a cut-off of 20.6\%. Comparable performance was obtained without manual artefact removal. RBD subjects also showed muscle bouts of higher amplitude and longer duration. RBDtector provides estimates of tonic, phasic, and any activity comparable to human scorings. RBDtector, which is freely available, can help identify RBD subjects and provides reliable RSWA metrics.}, language = {en} } @article{SavitskayaZhantlessovaKistaubayevaetal.2023, author = {Savitskaya, Irina and Zhantlessova, Sirina and Kistaubayeva, Aida and Ignatova, Ludmila and Shokatayeva, Dina and Sinyavsky, Yuriy and Kushugulova, Almagul and Digel, Ilya}, title = {Prebiotic cellulose-pullulan matrix as a "vehicle" for probiotic biofilm delivery to the host large intestine}, series = {Polymers}, journal = {Polymers}, number = {16(1)}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/polym16010030}, pages = {Artikel 30}, year = {2023}, abstract = {This study describes the development of a new combined polysaccharide-matrix-based technology for the immobilization of Lactobacillus rhamnosus GG (LGG) bacteria in biofilm form. The new composition allows for delivering the bacteria to the digestive tract in a manner that improves their robustness compared with planktonic cells and released biofilm cells. Granules consisting of a polysaccharide matrix with probiotic biofilms (PMPB) with high cell density (>9 log CFU/g) were obtained by immobilization in the optimized nutrient medium. Successful probiotic loading was confirmed by fluorescence microscopy and scanning electron microscopy. The developed prebiotic polysaccharide matrix significantly enhanced LGG viability under acidic (pH 2.0) and bile salt (0.3\%) stress conditions. Enzymatic extract of feces, mimicking colon fluid in terms of cellulase activity, was used to evaluate the intestinal release of probiotics. PMPB granules showed the ability to gradually release a large number of viable LGG cells in the model colon fluid. In vivo, the oral administration of PMPB granules in rats resulted in the successful release of probiotics in the colon environment. The biofilm-forming incubation method of immobilization on a complex polysaccharide matrix tested in this study has shown high efficacy and promising potential for the development of innovative biotechnologies.}, language = {en} } @article{HendersonMclaughlinScheeretal.2015, author = {Henderson, Colin J. and Mclaughlin, Lesley A. and Scheer, Nico and Stanley, Lesley A. and Wolf, C. Roland}, title = {Cytochrome b5 Is a Major Determinant of Human Cytochrome P450 CYP2D6 and CYP3A4 Activity In Vivo s}, series = {Molecular Pharmacology}, volume = {87}, journal = {Molecular Pharmacology}, number = {4}, publisher = {ASPET}, address = {Bethesda}, issn = {1521-0111}, doi = {10.1124/mol.114.097394}, pages = {733 -- 739}, year = {2015}, language = {en} } @article{KapelyukhHendersonScheeretal.2019, author = {Kapelyukh, Yury and Henderson, Colin James and Scheer, Nico and Rode, Anja and Wolf, Charles Roland}, title = {Defining the contribution of CYP1A1 and CYP1A2 to drug metabolism using humanized CYP1A1/1A2 and Cyp1a1/Cyp1a2 KO mice}, series = {Drug Metabolism and Disposition}, journal = {Drug Metabolism and Disposition}, number = {Early view}, doi = {10.1124/dmd.119.087718}, pages = {43 Seiten}, year = {2019}, language = {en} } @article{Timme2019, author = {Timme, Michael}, title = {Die Unwirksamkeit von auf {\"O}ffnungsklauseln in Gemeinschaftsordnungen fußenden Beschl{\"u}ssen}, series = {Monatsschrift f{\"u}r deutsches Recht}, journal = {Monatsschrift f{\"u}r deutsches Recht}, number = {15}, publisher = {Verlag Dr. Otto Schmidt}, address = {K{\"o}ln}, issn = {0340-1812}, doi = {10.9785/mdtr-2019-731509}, pages = {904 -- 905}, year = {2019}, language = {de} } @article{AnikTuelbentci1973, author = {Anik, Sabri and Tuelbentci, K.}, title = {Lichtbogenschweißen : Untersuchung der Schweißschlacke und der Wirkungen auf das Entfernen der Schlacke beim Lichtbogenschweißen ; Teil 1}, series = {Technische Rundschau : TR ; das Schweizer Industrie-Magazin}, volume = {65}, journal = {Technische Rundschau : TR ; das Schweizer Industrie-Magazin}, number = {48}, publisher = {Medtrix Group}, address = {Basel}, issn = {0040-148X}, pages = {13 -- 15}, year = {1973}, language = {de} } @article{vonKnobelsdorfBrenkenhoffFrauenrathProthmannetal.2010, author = {von Knobelsdorf-Brenkenhoff, Florian and Frauenrath, Tobias and Prothmann, Marcel and Dieringer, Matthias A. and Hezel, Fabian and Renz, Wolfgang and Kretschel, Kerstin and Niendorf, Thoralf and Schulz-Menger, Jeanette}, title = {Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla—a pilot study}, volume = {20}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {0938-7994}, doi = {10.1007/s00330-010-1888-2}, pages = {2844 -- 2852}, year = {2010}, abstract = {Objectives Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T. Methods A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated. Results All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm. Conclusions This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T.}, 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{DanhoNaithaniSasakietal.1980, author = {Danho, Waleed and Naithani, Vinod K. and Sasaki, Andr{\´e} N. and F{\"o}hles, Joseph and Berndt, Heinz and [u.a.],}, title = {Human proinsulin, VII : synthesis of two protected peptides corresponding to the sequences 1—45 and 46—86 of the prohormone}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {361}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {1}, issn = {1437-4315}, doi = {10.1515/bchm2.1980.361.1.857}, pages = {857 -- 863}, year = {1980}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Rothman-Woodroofe symmetry test statistic revisited}, series = {Computational Statistics \& Data Analysis}, volume = {2020}, journal = {Computational Statistics \& Data Analysis}, number = {142}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0167-9473}, doi = {10.1016/j.csda.2019.106837}, pages = {Artikel 106837}, year = {2020}, abstract = {The Rothman-Woodroofe symmetry test statistic is revisited on the basis of independent but not necessarily identically distributed random variables. The distribution-freeness if the underlying distributions are all symmetric and continuous is obtained. The results are applied for testing symmetry in a meta-analysis random effects model. The consistency of the procedure is discussed in this situation as well. A comparison with an alternative proposal from the literature is conducted via simulations. Real data are analyzed to demonstrate how the new approach works in practice.}, 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{KarschuckKaulenPoghossianetal.2021, author = {Karschuck, Tobias and Kaulen, Corinna and Poghossian, Arshak and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef}, title = {Gold nanoparticle-modified capacitive field-effect sensors: Studying the surface density of nanoparticles and coupling of charged polyelectrolyte macromolecules}, series = {Electrochemical Science Advances}, volume = {2}, journal = {Electrochemical Science Advances}, number = {5}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0938-5193}, doi = {10.1002/elsa.202100179}, pages = {10 Seiten}, year = {2021}, abstract = {The coupling of ligand-stabilized gold nanoparticles with field-effect devices offers new possibilities for label-free biosensing. In this work, we study the immobilization of aminooctanethiol-stabilized gold nanoparticles (AuAOTs) on the silicon dioxide surface of a capacitive field-effect sensor. The terminal amino group of the AuAOT is well suited for the functionalization with biomolecules. The attachment of the positively-charged AuAOTs on a capacitive field-effect sensor was detected by direct electrical readout using capacitance-voltage and constant capacitance measurements. With a higher particle density on the sensor surface, the measured signal change was correspondingly more pronounced. The results demonstrate the ability of capacitive field-effect sensors for the non-destructive quantitative validation of nanoparticle immobilization. In addition, the electrostatic binding of the polyanion polystyrene sulfonate to the AuAOT-modified sensor surface was studied as a model system for the label-free detection of charged macromolecules. Most likely, this approach can be transferred to the label-free detection of other charged molecules such as enzymes or antibodies.}, language = {en} } @article{HagebeukerLangeRingbeck2004, author = {Hagebeuker, Bianca and Lange, Robert and Ringbeck, Thorsten}, title = {Bildverarbeitung mit der dritten Dimension : wenn die Pixel auch Laufzeiten auswerten}, series = {Sensor-Report : Sensorik, Messtechnik, Bildverarbeitung, Fabrikautomation. - 2004, H. 2}, journal = {Sensor-Report : Sensorik, Messtechnik, Bildverarbeitung, Fabrikautomation. - 2004, H. 2}, publisher = {Rek \& Thomas}, address = {St. Gallen}, issn = {0179-9592}, pages = {11 -- 17}, year = {2004}, language = {de} }