@article{StreeseKotliarDeiserothetal.2020, author = {Streese, Lukas and Kotliar, Konstantin and Deiseroth, Arne and Infanger, Denis and Gugleta, Konstantin and Schmaderer, Christoph and Hanssen, Henner}, title = {Retinal endothelial function in cardiovascular risk patients: A randomized controlled exercise trial}, series = {Scandinavian Journal of Medicine and Science in Sports}, volume = {30}, journal = {Scandinavian Journal of Medicine and Science in Sports}, number = {2}, publisher = {Wiley}, address = {Oxford}, issn = {1600-0838}, doi = {10.1111/sms.13560}, pages = {272 -- 280}, year = {2020}, abstract = {The aim of this study was to investigate, for the first time, the effects of high-intensity interval training (HIIT) on retinal microvascular endothelial function in cardiovascular (CV) risk patients. In the randomized controlled trial, middle-aged and previously sedentary patients with increased CV risk (aged 58 ± 6 years) with ≥ two CV risk factors were randomized into a 12-week HIIT (n = 33) or control group (CG, n = 36) with standard physical activity recommendations. A blinded examiner measured retinal endothelial function by flicker light-induced maximal arteriolar (ADmax) and venular (VDmax) dilatation as well as the area under the arteriolar (AFarea) and venular (VFarea) flicker curve using a retinal vessel analyzer. Standardized assessments of CV risk factors, cardiorespiratory fitness, and retinal endothelial function were performed before and after HIIT. HIIT reduced body mass index, fat mass, and low-density lipoprotein and increased muscle mass and peak oxygen uptake (VO2peak). Both ADmax (pre: 2.7 ± 2.1\%, post: 3.0 ± 2.2\%, P = .018) and AFarea (pre: 32.6 ± 28.4\%*s, post: 37.7 ± 30.6\%*s, P = .016) increased after HIIT compared with CG (ADmax, pre: 3.2 ± 1.8\%, post: 2.9 ± 1.8\%, P = .254; AFarea, pre: 41.6 ± 28.5\%*s, post: 37.8 ± 27.0\%*s, P = .186). Venular function remained unchanged after HIIT. There was a significant association between ∆-change VO2peak and ∆-changes ADmax and AFarea (P = .026, R² = 0.073; P = .019, R² = 0.081, respectively). 12-weeks of HIIT improved retinal endothelial function in middle-aged patients with increased CV risk independent of the reduction in classical CV risk factors. Exercise has the potential to reverse or at least postpone progression of small vessel disease in older adults with increased CV risk under standard medication. Dynamic retinal vessel analysis seems to be a sensitive tool to detect treatment effects of exercise interventions on retinal microvascular endothelial function in middle-aged individuals with increased CV risk.}, language = {en} } @article{AlexopoulosHoffschmidt2017, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard}, title = {Advances in solar tower technology}, series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, volume = {6}, journal = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2041-840X}, doi = {10.1002/wene.217}, pages = {1 -- 19}, year = {2017}, language = {en} } @article{FiedlerOrzadaFloeseretal.2021, author = {Fiedler, Thomas M. and Orzada, Stephan and Fl{\"o}ser, Martina and Rietsch, Stefan H. G. and Quick, Harald H. and Ladd, Mark E. and Bitz, Andreas}, title = {Performance analysis of integrated RF microstrip transmit antenna arrays with high channel count for body imaging at 7 T}, series = {NMR in Biomedicine}, volume = {34}, journal = {NMR in Biomedicine}, number = {7}, publisher = {Wiley}, address = {Weinheim}, issn = {0952-3480 (ISSN)}, doi = {10.1002/nbm.4515}, pages = {18 SeitenWiley}, year = {2021}, abstract = {The aim of the current study was to investigate the performance of integrated RF transmit arrays with high channel count consisting of meander microstrip antennas for body imaging at 7 T and to optimize the position and number of transmit ele- ments. RF simulations using multiring antenna arrays placed behind the bore liner were performed for realistic exposure conditions for body imaging. Simulations were performed for arrays with as few as eight elements and for arrays with high channel counts of up to 48 elements. The B1+ field was evaluated regarding the degrees of freedom for RF shimming in the abdomen. Worst-case specific absorption rate (SARwc ), SAR overestimation in the matrix compression, the number of virtual obser- vation points (VOPs) and SAR efficiency were evaluated. Constrained RF shimming was performed in differently oriented regions of interest in the body, and the devia- tion from a target B1+ field was evaluated. Results show that integrated multiring arrays are able to generate homogeneous B1+ field distributions for large FOVs, espe- cially for coronal/sagittal slices, and thus enable body imaging at 7 T with a clinical workflow; however, a low duty cycle or a high SAR is required to achieve homoge- neous B1+ distributions and to exploit the full potential. In conclusion, integrated arrays allow for high element counts that have high degrees of freedom for the pulse optimization but also produce high SARwc , which reduces the SAR accuracy in the VOP compression for low-SAR protocols, leading to a potential reduction in array performance. Smaller SAR overestimations can increase SAR accuracy, but lead to a high number of VOPs, which increases the computational cost for VOP evaluation and makes online SAR monitoring or pulse optimization challenging. Arrays with interleaved rings showed the best results in the study.}, language = {en} } @article{TaddeiButenwegKlinkel2015, author = {Taddei, Francesca and Butenweg, Christoph and Klinkel, S.}, title = {Parametric investigation of the soil-structure interaction effects on the dynamic behaviour of a shallow foundation supported wind turbine considering a layered soil}, series = {Wind energy : an international journal for progress and applications in wind power conversion technology}, volume = {Volume 18}, journal = {Wind energy : an international journal for progress and applications in wind power conversion technology}, number = {Issue 3}, publisher = {Wiley}, address = {Weinheim}, issn = {1099-1824 (E-Journal); 1095-4244 (Print)}, doi = {10.1002/we.1703}, pages = {399 -- 417}, year = {2015}, language = {en} } @article{AlexyukBogoyavlenskiyAlexyuketal.2021, author = {Alexyuk, Madina and Bogoyavlenskiy, Andrey and Alexyuk, Pavel and Moldakhanov, Yergali and Berezin, Vladimir and Digel, Ilya}, title = {Epipelagic microbiome of the Small Aral Sea: Metagenomic structure and ecological diversity}, series = {MicrobiologyOpen}, volume = {10}, journal = {MicrobiologyOpen}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2045-8827}, doi = {10.1002/mbo3.1142}, pages = {1 -- 10}, year = {2021}, abstract = {Microbial diversity studies regarding the aquatic communities that experienced or are experiencing environmental problems are essential for the comprehension of the remediation dynamics. In this pilot study, we present data on the phylogenetic and ecological structure of microorganisms from epipelagic water samples collected in the Small Aral Sea (SAS). The raw data were generated by massive parallel sequencing using the shotgun approach. As expected, most of the identified DNA sequences belonged to Terrabacteria and Actinobacteria (40\% and 37\% of the total reads, respectively). The occurrence of Deinococcus-Thermus, Armatimonadetes, Chloroflexi in the epipelagic SAS waters was less anticipated. Surprising was also the detection of sequences, which are characteristic for strict anaerobes—Ignavibacteria, hydrogen-oxidizing bacteria, and archaeal methanogenic species. We suppose that the observed very broad range of phylogenetic and ecological features displayed by the SAS reads demonstrates a more intensive mixing of water masses originating from diverse ecological niches of the Aral-Syr Darya River basin than presumed before.}, language = {en} } @incollection{Dachwald2010, author = {Dachwald, Bernd}, title = {Solar sail dynamics and control}, series = {Encyclopedia of Aerospace Engineering}, booktitle = {Encyclopedia of Aerospace Engineering}, publisher = {Wiley}, address = {Hoboken}, doi = {10.1002/9780470686652.eae292}, year = {2010}, abstract = {Solar sails are large and lightweight reflective structures that are propelled by solar radiation pressure. This chapter covers their orbital and attitude dynamics and control. First, the advantages and limitations of solar sails are discussed and their history and development status is outlined. Because the dynamics of solar sails is governed by the (thermo-)optical properties of the sail film, the basic solar radiation pressure force models have to be described and compared before parameters to measure solar sail performance can be defined. The next part covers the orbital dynamics of solar sails for heliocentric motion, planetocentric motion, and motion at Lagrangian equilibrium points. Afterwards, some advanced solar radiation pressure force models are described, which allow to quantify the thrust force on solar sails of arbitrary shape, the effects of temperature, of light incidence angle, of surface roughness, and the effects of optical degradation of the sail film in the space environment. The orbital motion of a solar sail is strongly coupled to its rotational motion, so that the attitude control of these soft and flexible structures is very challenging, especially for planetocentric orbits that require fast attitude maneuvers. Finally, some potential attitude control methods are sketched and selection criteria are given.}, language = {en} } @article{VoigtSchroeterJuergenetal.2013, author = {Voigt, Birgit and Schroeter, Rebecca and J{\"u}rgen, Britta and Albrecht, Dirk and Evers, Stefan and Bongaerts, Johannes and Maurer, Karl-Heinz and Schweder, Thomas and Hecker, Michael}, title = {The response of Bacillus licheniformis to heat and ethanol stress and the role of the SigB regulon}, series = {Proteomics}, volume = {Vol. 13}, journal = {Proteomics}, number = {Iss. 14}, publisher = {Wiley}, address = {Weinheim}, issn = {1615-9861 (E-Journal); 1615-9853 (Print)}, pages = {2140 -- 2146}, year = {2013}, language = {en} } @article{LyonsMikuckiGermanetal.2019, author = {Lyons, W. Berry and Mikucki, Jill A. and German, Laura A. and Welch, Kathleen A. and Welch, Susan A. and Gardener, Christopher B. and Tulaczyk, Slawek M. and Pettit, Erin C. and Kowalski, Julia and Dachwald, Bernd}, title = {The Geochemistry of Englacial Brine from Taylor Glacier, Antarctica}, series = {Journal of Geophysical Research: Biogeosciences}, journal = {Journal of Geophysical Research: Biogeosciences}, publisher = {Wiley}, address = {Hoboken}, issn = {2169-8961}, doi = {10.1029/2018JG004411}, year = {2019}, 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{CiritsisHorbachStaatetal.2018, author = {Ciritsis, Alexander and Horbach, Andreas and Staat, Manfred and Kuhl, Christiane K. and Kraemer, Nils Andreas}, title = {Porosity and tissue integration of elastic mesh implants evaluated in vitro and in vivo}, series = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials}, volume = {106}, journal = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials}, number = {2}, publisher = {Wiley}, address = {New York, NY}, issn = {1552-4981}, doi = {10.1002/jbm.b.33877}, pages = {827 -- 833}, year = {2018}, abstract = {Purpose In vivo, a loss of mesh porosity triggers scar tissue formation and restricts functionality. The purpose of this study was to evaluate the properties and configuration changes as mesh deformation and mesh shrinkage of a soft mesh implant compared with a conventional stiff mesh implant in vitro and in a porcine model. Material and Methods Tensile tests and digital image correlation were used to determine the textile porosity for both mesh types in vitro. A group of three pigs each were treated with magnetic resonance imaging (MRI) visible conventional stiff polyvinylidene fluoride meshes (PVDF) or with soft thermoplastic polyurethane meshes (TPU) (FEG Textiltechnik mbH, Aachen, Germany), respectively. MRI was performed with a pneumoperitoneum at a pressure of 0 and 15 mmHg, which resulted in bulging of the abdomen. The mesh-induced signal voids were semiautomatically segmented and the mesh areas were determined. With the deformations assessed in both mesh types at both pressure conditions, the porosity change of the meshes after 8 weeks of ingrowth was calculated as an indicator of preserved elastic properties. The explanted specimens were examined histologically for the maturity of the scar (collagen I/III ratio). Results In TPU, the in vitro porosity increased constantly, in PVDF, a loss of porosity was observed under mild stresses. In vivo, the mean mesh areas of TPU were 206.8 cm2 (± 5.7 cm2) at 0 mmHg pneumoperitoneum and 274.6 cm2 (± 5.2 cm2) at 15 mmHg; for PVDF the mean areas were 205.5 cm2 (± 8.8 cm2) and 221.5 cm2 (± 11.8 cm2), respectively. The pneumoperitoneum-induced pressure increase resulted in a calculated porosity increase of 8.4\% for TPU and of 1.2\% for PVDF. The mean collagen I/III ratio was 8.7 (± 0.5) for TPU and 4.7 (± 0.7) for PVDF. Conclusion The elastic properties of TPU mesh implants result in improved tissue integration compared to conventional PVDF meshes, and they adapt more efficiently to the abdominal wall. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 827-833, 2018.}, language = {en} } @article{TippkoetterAlKaidyWollnyetal.2013, author = {Tippk{\"o}tter, Nils and Al-Kaidy, Huschyar and Wollny, Steffen and Ulber, Roland}, title = {Functionalized magnetizable particles for downstream processing in single-use systems}, series = {Chemie Ingenieur Technik}, volume = {85}, journal = {Chemie Ingenieur Technik}, number = {1-2: Special Issue: Single-Use Technology}, publisher = {Wiley}, address = {Weinheim}, doi = {10.1002/cite.201200130}, pages = {76 -- 86}, year = {2013}, abstract = {Biotechnological downstream processing is usually an elaborate procedure, requiring a multitude of unit operations to isolate the target component. Besides the disadvantageous space-time yield, the risks of cross-contaminations and product loss grow fast with the complexity of the isolation procedure. A significant reduction of unit operations can be achieved by application of magnetic particles, especially if these are functionalized with affinity ligands. As magnetic susceptible materials are highly uncommon in biotechnological processes, target binding and selective separation of such particles from fermentation or reactions broths can be done in a single step. Since the magnetizable particles can be produced from iron salts and low priced polymers, a single-use implementation of these systems is highly conceivable. In this article, the principles of magnetizable particles, their synthesis and functionalization are explained. Furthermore, applications in the area of reaction engineering, microfluidics and downstream processing are discussed focusing on established single-use technologies and development potential.}, language = {en} } @article{MolinnusBaeckerIkenetal.2015, author = {Molinnus, Denise and B{\"a}cker, Matthias and Iken, Heiko and Poghossian, Arshak and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Concept for a biomolecular logic chip with an integrated sensor and actuator function}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431913}, pages = {1382 -- 1388}, year = {2015}, abstract = {A concept for a new generation of an integrated multi-functional biosensor/actuator system is developed, which is based on biomolecular logic principles. Such a system is expected to be able to detect multiple biochemical input signals simultaneously and in real-time and convert them into electrical output signals with logical operations such as OR, AND, etc. The system can be designed as a closed-loop drug release device triggered by an enzyme logic gate, while the release of the drug induced by the actuator at the required dosage and timing will be controlled by an additional drug sensor. Thus, the system could help to make an accurate and specific diagnosis. The presented concept is exemplarily demonstrated by using an enzyme logic gate based on a glucose/glucose oxidase system, a temperature-responsive hydrogel mimicking the actuator function and an insulin (drug) sensor. In this work, the results of functional testing of individual amperometric glucose and insulin sensors as well as an impedimetric sensor for the detection of the hydrogel swelling/shrinking are presented.}, language = {en} } @article{ThielTippkoetterSucketal.2013, author = {Thiel, Alexander and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland}, title = {New zeolite adsorbents for downstream processing of polyphenols from renewable resources}, series = {Engineering in Life Sciences}, volume = {13}, journal = {Engineering in Life Sciences}, number = {3}, publisher = {Wiley}, address = {Weinheim}, doi = {10.1002/elsc.201200188}, pages = {239 -- 246}, year = {2013}, abstract = {Commercial materials with polyvinylpolypyrrolidone and polymeric amberlites (XAD7HP, XAD16) are commonly used for the adsorptive downstream processing of polyphenols from renewable resources. In this study, beta-zeolite-based adsorbent systems were examined, and their properties were compared to organic resins. Batch adsorption experiments were conducted with synthetic solutions of major polyphenols. Adsorption isotherms and desorption characteristics of individual adsorbent were determined based on these results. Maximum adsorption capacities were calculated using the Langmuir model. For example, the zeolites had capacities up to 203.2 mg/g for ferulic acid. To extend these results to a complex system, additional experiments were performed on rapeseed meal and wheat seed extracts as representative renewable resources. HPLC analysis showed that with 7.5\% w/v, which is regarded as the optimum amount of zeolites, zeolites A and B could bind 100\% of the major polyphenols as well as release polyphenols at high yields. Additionally, regeneration experiments were performed with isopropyl alcohol at 99°C to evaluate how zeolites regenerate under mild conditions. The results showed only a negligible loss of adsorption capacity and no loss of desorption capacity. In summary, it was concluded that beta-zeolites were promising adsorbents for developing new processes to isolate polyphenols from renewable resources.}, language = {en} } @article{MolinnusPoghossianKeusgenetal.2017, author = {Molinnus, Denise and Poghossian, Arshak and Keusgen, Michael and Katz, Evgeny and Sch{\"o}ning, Michael Josef}, title = {Coupling of Biomolecular Logic Gates with Electronic Transducers: From Single Enzyme Logic Gates to Sense/Act/Treat Chips}, series = {Electroanalysis}, volume = {29}, journal = {Electroanalysis}, number = {8}, publisher = {Wiley}, address = {Weinheim}, issn = {1521-4109}, doi = {10.1002/elan.201700208}, pages = {1840 -- 1849}, year = {2017}, abstract = {The integration of biomolecular logic principles with electronic transducers allows designing novel digital biosensors with direct electrical output, logically triggered drug-release, and closed-loop sense/act/treat systems. This opens new opportunities for advanced personalized medicine in the context of theranostics. In the present work, we will discuss selected examples of recent developments in the field of interfacing enzyme logic gates with electrodes and semiconductor field-effect devices. Special attention is given to an enzyme OR/Reset logic gate based on a capacitive field-effect electrolyte-insulator-semiconductor sensor modified with a multi-enzyme membrane. Further examples are a digital adrenaline biosensor based on an AND logic gate with binary YES/NO output and an integrated closed-loop sense/act/treat system comprising an amperometric glucose sensor, a hydrogel actuator, and an insulin (drug) sensor.}, language = {en} } @article{BegingLeinhosJablonskietal.2015, author = {Beging, Stefan and Leinhos, Marcel and Jablonski, Melanie and Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Studying the spatially resolved immobilisation of enzymes on a capacitive field-effect structure by means of nano-spotting}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431891}, pages = {1353 -- 1358}, year = {2015}, language = {en} } @article{JungStaat2019, author = {Jung, Alexander and Staat, Manfred}, title = {Modeling and simulation of human induced pluripotent stem cell-derived cardiac tissue}, series = {GAMM - Mitteilungen der Gesellschaft f{\"u}r Angewandte Mathematik und Mechanik}, volume = {42}, journal = {GAMM - Mitteilungen der Gesellschaft f{\"u}r Angewandte Mathematik und Mechanik}, number = {4}, publisher = {Wiley}, address = {Weinheim}, issn = {1522-2608}, doi = {10.1002/gamm.201900002}, pages = {11 Seiten}, year = {2019}, language = {en} } @article{SiqueiraAbouzarBaeckeretal.2009, author = {Siqueira, Jos{\´e} R. Jr. and Abouzar, Maryam H. and B{\"a}cker, Matthias and Zucolotto, Valtencir and Poghossian, Arshak and Oliveira, Osvaldo N. Jr. and Sch{\"o}ning, Michael Josef}, title = {Carbon nanotubes in nanostructured films: Potential application as amperometric and potentiometric field-effect (bio-)chemical sensors}, series = {physica status solidi (a) . 206 (2009), H. 3}, journal = {physica status solidi (a) . 206 (2009), H. 3}, publisher = {Wiley}, address = {Weinheim}, isbn = {1862-6319}, pages = {462 -- 467}, year = {2009}, language = {en} } @article{TippkoetterWollnySucketal.2014, author = {Tippk{\"o}tter, Nils and Wollny, Steffen and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland}, title = {Recycling of spent oil bleaching earth as source of glycerol for the anaerobic production of acetone, butanol, and ethanol with Clostridium diolis and lipolytic Clostridium lundense}, series = {Engineering in Life Sciences}, volume = {14}, journal = {Engineering in Life Sciences}, number = {4}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1618-2863}, doi = {10.1002/elsc.201300113}, pages = {425 -- 432}, year = {2014}, abstract = {A major part of edible oil is subjected to bleaching procedures, primarily with minerals applied as adsorbers. Their recycling is currently done either by regaining the oil via organic solvent extraction or by using the spent bleaching earth (SBE) as additive for animal feed, etc. As a new method, the reutilization of the by-product SBE for the microbiologic formation of acetone, butanol, and ethanol (ABE) is presented as proof-of-concept. The SBE was taken from a palm oil cleaning process. The recycling concept is based on the application of lipolytic clostridia strains. Due to considerably long fermentation times, co-fermentation with Candida rugosa and enzymatic hydrolyses of the bound oil with a subsequent clostridia fermentation are shown as alternative routes. Anaerobic fermentations under comparison of different clostridia strains were performed with glycerol media, enzymatically hydrolyzed palm oil and SBE. Solutes, side product compositions and productivities were quantified via HPLC. A successful production of ABE solutes from SBE has been done with a yield of 0.15 g butanol per gram of bound glycerol. Thus, the biotechnological recycling of the waste stream is possible in principle. Inhibition of the substrate suspension has been observed. A chromatographic ion-exchange of substrates increased the biomass concentration.}, language = {en} } @article{AlKaidyDuweHusteretal.2015, author = {Al-Kaidy, Huschyar and Duwe, Anna and Huster, Manuel and Muffler, Kai and Schlegel, Christin and Tim, Sieker and Stadtm{\"u}ller, Ralf and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Biotechnology and bioprocess engineering - from the first ullmann's article to recent trends}, series = {ChemBioEng Reviews}, volume = {2}, journal = {ChemBioEng Reviews}, number = {3}, publisher = {Wiley}, address = {Weinheim}, doi = {10.1002/cben.201500008}, pages = {175 -- 184}, year = {2015}, abstract = {For several thousand years, biotechnology and its associated technical processes have had a great impact on the development of mankind. Based on empirical methods, in particular for the production of foodstuffs and daily commodities, these disciplines have become one of the most innovative future issues. Due to the increasing detailed understanding of cellular processes, production strains can now be optimized. In combination with modern bioprocesses, a variety of bulk and fine chemicals as well as pharmaceuticals can be produced efficiently. In this article, some of the current trends in biotechnology are discussed.}, language = {en} } @article{SchusserLeinhosBaeckeretal.2013, author = {Schusser, Sebastian and Leinhos, Marcel and B{\"a}cker, Matthias and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Impedance spectroscopy: A tool for real-time in situ monitoring of the degradation of biopolymers}, series = {Physica Status Solidi (A)}, volume = {210}, journal = {Physica Status Solidi (A)}, number = {5}, publisher = {Wiley}, address = {Weinheim}, issn = {1521-396X ; 0031-8965}, doi = {10.1002/pssa.201200941}, pages = {905 -- 910}, year = {2013}, abstract = {Investigation of the degradation kinetics of biodegradable polymers is essential for the development of implantable biomedical devices with predicted biodegradability. In this work, an impedimetric sensor has been applied for real-time and in situ monitoring of degradation processes of biopolymers. The sensor consists of two platinum thin-film electrodes covered by a polymer film to be studied. The benchmark biomedical polymer poly(D,L-lactic acid) (PDLLA) was used as a model system. PDLLA films were deposited on the sensor structure from a polymer solution by using the spin-coating method. The degradation kinetics of PDLLA films have been studied in alkaline solutions of pH 9 and 12 by means of an impedance spectroscopy (IS) method. Any changes in a polymer capacitance/resistance induced by water uptake and/or polymer degradation will modulate the global impedance of the polymer-covered sensor that can be used as an indicator of the polymer degradation. The degradation rate can be evaluated from the time-dependent impedance spectra. As expected, a faster degradation has been observed for PDLLA films exposed to pH 12 solution.}, language = {en} }