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Mit dem hier vorliegenden Tagungsband des landesweiten HAW-Forschungstages 2024 an der Hochschule Kaiserslautern ermöglichen wir allen Teilnehmenden und Interessierten einen Einblick in die Vielfalt und Exzellenz der Forschung an unseren Hochschulen in Rheinland-Pfalz. Der HAW-Forschungstag 2024 steht unter dem Motto "Die Zukunft ist WIR – Wissenschaft, Innovation, Rheinland-Pfalz". Unsere Forschungsthemen reichen von Gestaltung über Life Sciences und Informatik bis hin zu Wirtschaft, Soziales und Gesundheit. Diese interdisziplinäre Ausrichtung spiegelt sich in den hier versammelten Beiträgen wider und verdeutlicht die Rolle der Hochschulen für Angewandte Wissenschaften als zentrale Player in der modernen Forschungslandschaft.
Since 1965 a cyanobacterial strain termed ‘Fischerella ambigua 108b’ was the object of several studies investigating its potential as a resource for new bioactive compounds in several European institutes. Over decades these investigations uncovered several unique small molecules and their respective biosynthetic pathways, including the polychlorinated triphenyls of the ambigol family and the tjipanazoles. However, the true taxonomic character of the producing strain remained concealed until now. Applying a polyphasic approach considering the phylogenetic position based on the 16S rRNA and the protein coding gene rbcLX, secondary structures and morphological features, we present the strain ‘Fischerella ambigua 108b’ as Symphyonema bifilamentata sp. nov. 97.28. Although there is the type species (holotype) S. sinense C.-C. Jao 1944 there is no authentic living strain or material for genetic analyses for the genus Symphyonema available. Thus we suggest and provide an epitypification of S. bifilamentata sp. nov. 97.28 as a valid reference for the genus Symphyonema. Its affiliation to the family Symphyonemataceae sheds not only new light on this rare taxon but also on the classes of bioactive metabolites of these heterocytous and true-branching cyanobacteria which we report here. We show conclusively that the literature on the isolation of bioactive products from this organism provides further support for a clear distinction between the secondary metabolism of Symphyonema bifilamentata sp. nov. 97.28 compared to related and other taxa, pointing to the assignment of this organism into a separate genus.
Bioweathering mediated by microorganisms plays a significant role in biogeo-chemical cycles on global scales over geological timescales. Single processes induced by specific taxa have been described but could rarely be demonstrated for complex communities that dominate whole landscapes. The recently discovered grit crust of the coastal Atacama Desert, which is a transitional community between a cryptogamic ground cover and a rock-bound lithic assemblage, offers
the unique chance to elucidate various bioweathering processes that occur simultaneously. Here, we present a bioweathering scenario of this biocenosis including processes such as penetration of the lithomatrix, microbial responses to wet-dry cycles, alkalinolysis, enzyme activity, and mineral re-localization. Frequently
occurring fog, for example, led to a volume increase of microorganisms and the lithomatrix. This, together with pH shifts and dust accumulation, consequently results in biophysical breakdown and the formation of a terrestrial protopedon, an initial stage of pedogenesis fueled by the grit crust.
Troxerutin (TRX) is a water-soluble flavonoid which occurs commonly in the edible plants.
Recent studies state that TRX improves the functionality of the nervous system and neutral-
izes Amyloid-ß induced neuronal toxicity. In this study, an in vitro assay based upon Neural
stem cell (NSCs) isolated from the subventricular zone of the postnatal balb/c mice was
established to explore the impact of TRX on individual neurogenesis processes in general
and neuroprotective effect against ß-amyloid 1–42 (Aß42) induced inhibition in differentia-
tion in particular. NSCs were identified exploiting immunostaining of the NSCs markers.
Neurosphere clonogenic assay and BrdU/Ki67 immunostaining were employed to unravel
the impact of TRX on proliferation. Differentiation experiments were carried out for a time
span lasting from 48 h to 7 days utilizing ß-tubulin III and GFAP as neuronal and astrocyte
marker respectively. Protective effects of TRX on Aß42 induced depression of NSCs differ-
entiation were determined after 48 h of application. A neurosphere migration assay was car-
ried out for 24 h in the presence and absence of TRX. Interestingly, TRX enhanced neuronal
differentiation of NSCs in a dose-dependent manner after 48 h and 7 days of incubation and
significantly enhanced neurite growth. A higher concentration of TRX also neutralized the
inhibitory effects of Aß42 on neurite outgrowth and length after 48 h of incubation. TRX sig-
nificantly stimulated cell migration. Overall, TRX not only promoted NSCs differentiation and
migration but also neutralized the inhibitory effects of Aß42 on NSCs. TRX, therefore, offers
an interesting lead structure from the perspective of drug design especially to promote neu-
rogenesis in neurological disorders i.e. Alzheimer’s disease.
Pumps have a wide range of applicat ions. Methods for fault detection of motors are
increasingly being used for pumps. In the context of this paper, a test bench is built to investigate
circulation pumps for faults. As a use case, the fault of impeller clogging was first measured and
then examined with the help of motor current signature analysis. It can be seen that there are four
frequencies at which there is an increase in amplitude in case of a fault. The sidebands around the
supply frequency are in particular f ocus. The clogging of three and four of a total of seven channels
leads to the highest amplitudes at the fault frequencies. The efficiency is reduced by 9 to 15% in case
of faulty opera tion. These results indicate that the implementation of fault detection algorithms on
the pump electronics represents added value for the pump operator. Furthermore, the results can be
transferred to other applications.
The service life of materials and components exposed to repeated mechanical loads is
limited, which is why the understanding of the damage evolution and estimating its fatigue life is of
high importance for its technical application. This paper shows how temperature and magnetic field
measurement methods can be used to describe the cyclic deformation behaviour of metallic materials
and to derive parameters from this, which are used in short-term methods to calculate the fatigue
life. Within the SteBLife (stepped-bar fatigue life) approach, only three to five fatigue tests with a
stepped fatigue specimen are required to determine a complete S–N or Woehler curve with scatter
bands for different failure probabilities. If only a trend S–N curve is required, the number of tests
can be reduced to a single fatigue test only. In the framework of this paper, these approaches will be
presented for normalised SAE 1045 (C45E) and quenched and tempered SAE 4140 (42CrMo4) steels.
Composites with reinforcements based on bast fibers such as flax, hemp and kenaf offer
many advantages such as weight reduction, improved specific impact, flexural, acoustic properties,
and balanced performance to cost that can be achieved by properly designing the material composition.
Their position is well established, especially in the nonstructural automotive applications. However,
in structural applications of composites, their mechanical property profile is not comparable to the
dominant reinforcements such as glass and carbon fibers. The low mechanical properties of these
composites could be improved by hybridization that involves adding high-performance fibers to the
bast fiber composites that could improve the low mechanical performance of the bast fiber composites.
The review presented in this article provides an overview of the developments in the field of hybrid
polymer composites composed of bio-based bast fibers with glass, carbon, and basalt fibers. The focus
areas are the composite manufacturing methods, the influence of hybridization on the mechanical
properties, and the applications of hybrid composites.
Encapsulated magnetic nanoparticles are of increasing interest for biomedical applications.
However, up to now, it is still not possible to characterize their localized magnetic properties within
the capsules. Magnetic Force Microscopy (MFM) has proved to be a suitable technique to image
magnetic nanoparticles at ambient conditions revealing information about the spatial distribution
and the magnetic properties of the nanoparticles simultaneously. However, MFM measurements
on magnetic nanoparticles lead to falsifications of the magnetic MFM signal due to the topographic
crosstalk. The origin of the topographic crosstalk in MFM has been proven to be capacitive coupling
effects due to distance change between the substrate and tip measuring above the nanoparticle. In this
paper, we present data fusion of the topography measurements of Atomic Force Microscopy (AFM)
and the phase image of MFM measurements in combination with the theory of capacitive coupling in
order to eliminate the topographic crosstalk in the phase image. This method offers a novel approach
for the magnetic visualization of encapsulated magnetic nanoparticles.
Iron oxide nanoparticles (IONs) are used in a number of applications from food to cosmetics and from medical
applications to magnetic storage. In spite of the 550 tons produced each year in Europe alone, no effective dose
limit recommendations are established and the overall risks connected to IONs are still debated. The incorporation
of IONs in daily life raises a concern about their effects on the environment, on living organisms, and on human
health. In this study, we used freshwater planarians to assess the nanoecotoxicity of IONs. Planarians are free-living
invertebrates known for their astonishing regenerative ability. Because of their sensitivity to toxicants, they are often used
to determine the effects of toxic, genotoxic, and carcinogenic environmental compounds with an approach in line with
the 3Rs (Reduce, Refine, Replace) principle. Planarians were exposed to IONs at concentrations up to 1 mg/ml and
their effects were evaluated at the behavioral, morphofunctional, and molecular levels, with a special emphasis on the
regeneration process. Our results indicate that IONs did not affect the stem cell population dynamics, nor did they induce
substantial changes in either homeostatic or regenerating planarians. As positive controls, gold nanoparticles coated
with the pro-apoptotic anti-cancer drug hexadecylmethylammonium bromide and highly concentrated polystyrene
nanoparticles were used; these all elicited toxic effects. Therefore, we conclude that IONs at environmental concen-
trations are safe for planarians, and that the planarian is a powerful model system that can replace vertebrate animal
models in nanoecotoxicology research and for nanoecotoxicology studies.
Magnetic force microscopy (MFM) has become a widely used tool for the characterization of magnetic properties. However, the
magnetic signal can be overlapped by additional forces acting on the tip such as electrostatic forces. In this work the possibility to
reduce capacitive coupling effects between tip and substrate is discussed in relation to the thickness of a dielectric layer introduced
in the system. Single superparamagnetic iron oxide nanoparticles (SPIONs) are used as a model system, because their magnetic
signal is contrariwise to the signal due to capacitive coupling so that it is possible to distinguish between magnetic and electric force
contributions. Introducing a dielectric layer between substrate and nanoparticle the capacitive coupling can be tuned and minimized
for thick layers. Using the theory of capacitive coupling and the magnetic point dipole–dipole model we could theoretically explain
and experimentally prove the phase signal for single superparamagnetic nanoparticles as a function of the layer thickness of the
dielectric layer. Tuning the capacitive coupling by variation of the dielectric layer thickness between nanoparticle and substrate
allows the distinction between the electric and the magnetic contributions to the MFM signal. The theory also predicts decreasing
topographic effects in MFM signals due to surface roughness of dielectric films with increasing film thickness.
A complete workflow for the differentiation and the dissociation of hiPSC-derived cardiospheres
(2018)
Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are an invaluable tool for both basic and translational cardiovascular research. The potential that these cells hold for therapy, disease modeling and drug discovery is hampered by several bottlenecks that currently limit both the yield and the efficiency of cardiac induction. Here, we present a complete workflow for the production of ready-to-use hiPSC-CMs in a dynamic suspension bioreactor. This includes the efficient and highly reproducible differentiation of hiPSCs into cardiospheres, which display enhanced physiological maturation compared to static 3D induction in hanging drops, and a novel papain-based dissociation method that offers higher yield and viability than the broadly used dissociation reagents TrypLE and Accutase. Molecular and functional analyses of the cardiomyocytes reseeded after dissociation confirmed both the identity and the functionality of the cells, which can be used in downstream applications, either as monolayers or spheroids.
Top-Down Fabricated Silicon Nanowire Arrays for Field-Effect Detection of Prostate-Specific Antigen
(2018)
Highly sensitive electrical detection of biomarkers for the
early stage screening of cancer is desired for future, ultrafast diagnostic
platforms. In the case of prostate cancer (PCa), the prostate-specific
antigen (PSA) is of prime interest and its detection in combination with
other PCa-relevant biomarkers in a multiplex approach is advised. Toward
this goal, we demonstrate the label-free, potentiometric detection of PSA
with silicon nanowire ion-sensitive field-effect transistor (Si NW-ISFET)
arrays. To realize the field-effect detection, we utilized the DNA aptamerreceptors specific for PSA, which were covalently and site-specifically
immobilized on Si NW-ISFETs. The platform was used for quantitative
detection of PSA and the change in threshold voltage of the Si NW-ISEFTs
was correlated with the concentration of PSA. Concentration-dependent
measurements were done in a wide range of 1 pg/mL to 1 μg/mL, which
covers the clinical range of interest. To confirm the PSA−DNA aptamer
binding on the Si NW surfaces, a sandwich-immunoassay based on chemiluminescence was implemented. The electrical
approach using the Si NW-ISFET platform shows a lower limit of detection and a wide dynamic range of the assay. In future,
our platform should be utilized to detect multiple biomarkers in one assay to obtain more reliable information about cancerrelated diseases
The detection of superparamagnetic nanoparticles by magnetic force microscopy (MFM) at the single particle level faces difficulties such as superposition of nonmagnetic signals caused by electrostatic interactions as well as reaching the resolution limits due to small magnetic interactions. In MFM the magnetic force is measured at a certain distance to the substrate following the topography measured in a first scan to avoid an influence of short range forces (lift mode). In this work we showed that performing MFM on superparamagnetic nanoparticles the increase of the tip-substrate distance above the nanoparticle in lift mode scans leads to a reduction of the electrostatic forces resulting in a positive phase shift in contrast to the negative phase shift of the attractive magnetic force. Identifying the electrostatic force in MFM on nanoparticles as a capacitive coupling effect between tip and substrate the origin of often seen topography mirroring in phase images of nanoparticles in general is theoretically explained and experimentally proved. Minimization of the capacitive coupling by adjusting the work function difference between tip and substrate as well as using an optimized tip allows the magnetic visualization of single 10 nm superparamagnetic iron oxide nanoparticles (SPIONs) at ambient conditions with and without an external magnetic field.
Weight-optimized component design as well as a reliable estimation of the lifetime of metallic materials and components requires a comprehensive understanding of fatigue processes and a systematic investigation of the underlying fatigue behavior. Therefore, nondestructive testing methods, digitalization of measurement techniques as well as signal processing can be combined with a short-term procedure in order to acquire potentially more information about fatigue processes, while experimental effort and costs are reduced significantly. This leads not only to considerable advantages over conventional methods for determining S-N curves, but also over established short-term procedures, due to the possibility of applying this information from just a few specimens to attain fatigue life calculations. The StressLifetc approach is a new short-term calculation method which considers the nonlinear relation between the elastic, elastic-plastic and plastic portion of the material response in the deformation process. Within the scope of the present work, the change in temperature of SAE 1045 (C45E) specimens was measured during fatigue tests via an infrared camera in order to feed the thermal response back into the new StressLifetc approach for a reliable fatigue life calculation.
The TriRhenaTech alliance presents the accepted papers of the 'Upper-Rhine Artificial Intelligence Symposium' held on October 27th 2021 in Kaiserslautern, Germany. Topics of the conference are applications of Artificial Intellgence in life sciences, intelligent systems, industry 4.0, mobility and others. The TriRhenaTech alliance is a network of universities in the Upper-Rhine Trinational Metropolitan Region comprising of the German universities of applied sciences in Furtwangen, Kaiserslautern, Karlsruhe, Offenburg and Trier, the Baden-Wuerttemberg Cooperative State University Loerrach, the French university network Alsace Tech (comprised of 14 'grandes écoles' in the fields of engineering, architecture and management) and the University of Applied Sciences and Arts Northwestern Switzerland. The alliance's common goal is to reinforce the transfer of knowledge, research, and technology, as well as the cross-border mobility of students.