Kiel University of Applied Sciences

Wu T., Blawert C., Serdechnova M., Zheludkevich M.L.

Plasma electrolytic oxidation (PEO) processing of light metals has been established for decades and is in increasing industrial use, even as an alternative surface treatment to produce multifunctional coatings with environmental-friendly processing concept. One of the benefits of PEO processing claimed already a couple of years ago was the ability to treat dissimilar metal joints, which can obviously improve the surface homogeneity and stability at the interface of the dissimilar components, especially impeding the galvanic corrosion due to the different electrochemical properties of each component. However, the progress and breakthrough develop slowly especially for the macro scales due to the much larger gap between each component. This literature review firstly demonstrates the still low number of studies reporting successful PEO treatment of material combination such as Mg/Al, Mg/Ti, Al/Ti and scarcely light metal combinations with steel. The main issues and challenges to performing PEO processing on the macro-scale dissimilar weldments were stated. On the other hand, dissimilar metal joints also widely exist in micrometer scale in alloys and metal matrix composites (MMCs). Moreover, there is a huge knowledge base on PEO treatment of such multiphase substrates. PEO processing of such complicated mixed microstructures is reviewed as well to reveal the basic problems. To some certain degree, these PEO-related studies on alloys and MMCs can be good examples to have an insight into the coating formation mechanism on macro-scaled dissimilar metal joints. Conclusions are drawn from the micro- to macroscale. Finally, critical access to the problems is given and possible solutions and reaming limitations are discussed.

Görtz S., Widell P.

AbstractIm Rahmen eines von der Bundesanstalt für Straßenwesen beauftragten Forschungsvorhabens wurde eine Datenbank mit 1530 Torsionsversuchen erstellt und hieran Bemessungsmodelle im Kontext der DIN EN 1992 bzw. der Nachrechnungsrichtlinie systematisch ausgewertet. Zielsetzung war es, einerseits Sicherheitsdefizite zu identifizieren und darüber hinaus Traglastpotenziale im Hinblick auf die Nachrechnung von Bestandsbauwerken aufzuzeigen.

Vanini U.

Thege B., Jansen-Schulz B.

Zusammenfassung Der Beitrag beschreibt erste Erfahrungen einer externen Gender Mainstreaming Beratung von Beteiligten verschiedener Fachvorhaben einer Landesverwaltung. Darin wurden die Anwendung einer 4‑Schritte-Matrix zur Genderanalyse erprobt und chancengerechte Umsetzungsmaßnahmen für die jeweiligen Fachvorhaben entwickelt. Die Beratung bezog sich auf die Befähigung der Beteiligten, gleichstellungsrelevante Aspekte bereits in der Planung eines Vorhabens identifizieren zu können, um mögliche geschlechtsspezifische Diskriminierungen zu vermeiden oder bestehende Nachteile auszugleichen.

Rass E., Unbehaun D., Aal K., Tandler J., Lenz G., Wulf V.

This paper presents the results of a long-term exploratory study that examined the social and emotional impact of using a social robot with a variety of applications to promote activities for people with advanced dementia and their caregivers. Qualitative data was collected over 10-months in a secured care environment in which we explored the appropriation of a social robot by 23 participants, including 13 PwAD, their family members, and professional caregivers. Our findings indicate that the use of the social robot demonstrated the potential to improve well-being, engagement, and social interaction of PwAD, even demonstrating the ability to create new memories and experiences. We discuss requirements and challenges in integrating social robots into secured care environments to provide a nuanced understanding for future research aiming for appropriate and inclusive care outcomes and socially embedded innovations that address the social actors involved and thus contribute to practical solutions for professional care.

Badri-Hoeher S., Wilts T., Schaefer L., Westphalen J., Winkler J., Isokeit C., Harlakin A., Hott M., Placzek J.M., Marx S., Volz M., Maehle E., Hoeher P.A.

Gharibzahedi S.M., Altintas Z.

New bioactive coatings with eryngo essential oil (EEO) nanoemulsions stabilized by ultrasonically-treated lesser mealworm protein isolate (LMPI) were developed to extend strawberry shelf life and quality. EEO due to high carvone (43.03 %), phenolics (87.45 mg gallic acid equivalent/g), flavonoids (13.56 mg quercetin equivalent/g), and carotenoids (635.07 mg/kg) contents exhibited a significant antioxidant activity comparable to ascorbic acid (AA) and BHT. Nanoemulsions stabilized with 9 % sonicated LMPI showed smaller droplet size, higher negative ζ-potential, and greater stability, turbidity, and encapsulation efficiency of EEO compared to those stabilized with native LMPI. The FTIR spectra showed that sonicated LMPI had structural changes enhancing its emulsifying activity, with key peaks indicating the presence of hydrogen bonds, carbonyl groups, and protein conformations in both EEO and LMPI. Strawberries coated with optimal EEO-loaded nanoemulsions showed superior quality with minimal storage-dependent physicochemical, textural, color, and sensory changes compared to control samples. This edible coating also maintained higher total monomeric anthocyanin and AA contents with lower peroxidase activity during storage than EEO-based coatings. However, no significant difference in superoxide dismutase activity between samples covered by EEO and EEO-loaded nanoemulsions over 14 days of storage was found. Bioactive nanoemulsions stabilized by insect proteins would be an eco-friendly and safe approach to upholding quality standards in stored fruits and vegetables.

Maki S., Al Awar S., Alhosani S., Alshamsi L., Alzaabi S., Ali Alsaadi M., Alhammadi M., Alhosani H., Salam G.S., Wójtowicz S., Zaręba K.

Background: Preconception health is critical for improving maternal and child health. The main objective of the study was to explore medical students’ health habits, quality of life, and knowledge of preconception healthcare. Methods: We conducted a cross-sectional study between 15 March 2023 and 31 May 2024 among medical students at United Arab Emirates University. To determine awareness and knowledge of preconception health, we administered a survey consisting of an author’s questionnaire with 35 questions covering sociodemographic characteristics and general knowledge of preconception health, as well as the WHO Quality of Life Scale-BREF (WHOQOL-BREF). Results: The participants were predominantly under 25 years old (98.5%), Emirati (91.1%), single (92.6%), and female (95.8%); only 3.4% had been pregnant before. Regarding health awareness and behaviors, a significant number of females (58.0%) had never visited a gynecologist. The majority of students (72.4%) participated in sports activities. The overall level of knowledge was low, with a mean level of 7.5 (SD = 6.36) out of 24. The Internet (webpages, blogs, webinars) (64.5%) was the major source of knowledge regarding healthcare information, followed by social media platforms (Twitter, Facebook, TikTok, Instagram) and mobile applications (57.5%), books (48.6%), and family members (57.0%). There was a statistically significant correlation between knowledge levels and the Internet (p < 0.004) or family (p < 0.001) as a source of knowledge. Additionally, there was a statistically significant positive correlation between knowledge and quality of life across all four WHOQOL domains. Conclusions: Medical knowledge might positively affect general well-being. Fostering stronger social networks and support systems could benefit preconceptional awareness and knowledge.

Krasodomska J., Eisenschmidt K.

ABSTRACTIntegrating environmental and social considerations into business strategies is critical to progress toward achieving sustainable development. The paper utilizes a sample comprising 364 companies listed on the Warsaw Stock Exchange (WSE) to identify the relationship between companies' corporate governance mechanisms and their environmental, social, and governance (ESG)‐related strategic and reporting decisions. The timeframe of the study takes into account a key moment characterized by significant changes to the WSE's corporate governance code of best practice. According to the study findings, companies are more likely to integrate social issues into business strategies than they are to integrate environmental concerns. The logit regression results suggest a significant positive relationship between the implementation of both a diversity policy on corporate governance bodies and remuneration mechanisms and the decision to integrate environmental and social issues into a company's business strategy and ESG strategy disclosure. In contrast, the implementation of effective internal management systems is significantly associated only with the decision to integrate social issues into a company's business strategy.

Olivares Moreno C.A., Ghaddar N., Sehit E., Schomäcker R., Altintas Z.

Although membrane technology has demonstrated outstanding pathogen removal capabilities, current commercial membranes are insufficient for removing small viruses at trace levels due to certain limitations. The theoretical and practical significance of developing a new form of hydrophilic, anti-fouling, and virus-specific ultra-purification membrane with high capturing and separation efficiency, stability, and throughput for water treatment is of the utmost importance. In this study, molecularly imprinted membranes (MIMs) were fabricated from polyvinylidene fluoride (PVDF) membranes utilizing novel surface hydrophilic modification techniques, followed by the immobilization of virus-specific molecularly imprinted nanoparticles (nanoMIPs) as synthetic receptors. Three distinct membrane functionalization strategies were established and optimized for the first time: membrane functionalization with (i) polyethyleneimine (PEI) and dopamine (DOP), (ii) PEI and 3-(chloropropyl)-trimethoxysilane (CTS), and (iii) chitosan (CS). Hydrophilicity was enhanced significantly as a result of these modification strategies. Additionally, the modifications enabled spacer arms between the membrane surface and the nanoMIPs to decrease steric hindrance. The surface chemistry, morphology, and membrane performance results from the characterization analysis of the MIMs demonstrated excellent hydrophilicity (e.g., the functionalized membrane presented 37.84° while the unmodified bare membrane exhibited 128.94° of water contact angle), higher permeation flux (145.96 L m

Görtz S., Lengert K., Glomb D., Kustermann A., Dauberschmidt C., Burgard S.

AbstractAufgrund chloridinduzierter Korrosion müssen Brückenkappen aus Stahlbeton regelmäßig bzw. vielfach häufiger als geplant erneuert werden. Im Rahmen eines vom Bundesministerium für Wirtschaft und Klimaschutz geförderten ZIM‐Projekts wurden Brückenkappen aus einer nichtmetallischen Basaltfaserstabbewehrung und einem Recyclingbeton entwickelt, sodass die Schwachstelle der Korrosion entschärft wird und die Materialien im Hinblick auf den Materialkreislauf zugleich besser ausgenutzt werden. Hierzu wurden gebogene Bewehrungselemente aus chloridunempfindlicher Basaltfaserstabbewehrung sowie ein Beton mit hohem Frost‐Tausalz‐Widerstand entwickelt, der aus bis zu 100 % recyclierter Gesteinskörnung besteht. Alle Teilentwicklungen wurden zu einem ganzheitlichen Ansatz vereint und ein Prototyp einer ressourcenschonenden und dauerhaften Brückenkappe erfolgreich hergestellt und getestet.

Chen J.N., Hasabnis G.K., Akin E., Gao G., Usha S.P., Süssmuth R., Altintas Z.

This study integrates dopamine (DA) electropolymerization, epitope imprinting, and nanomaterials (i.e., gold nanoparticles (AuNP) and graphene quantum dots (GQD)) to develop three distinct electrochemical sensors (DA-AuNP-MIP, DA-GQD-MIP, and DA-AuNP-GQD-MIP) for detecting cardiac troponin I (cTnI) with assessing their sensitivity, selectivity, and specificity profiles. The sensors exhibited high affinity for the target biomarker, enabling detection within a concentration range of 0.01-20 ng mL-1, with dissociation constants ranging from 2.7-69 pM. The successful fabrication of sensors was also confirmed through atomic force microscopy (AFM), scanning electron microscopy (SEM), fluorescence microscopy, contact angle measurements, cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS). The cTnI selectivity assessment of imprinted nanosensors compared to their non-imprinted counterparts at 0.01-2.5 ng mL-1 showed that the DA-AuNP-GQD-MIP sensor yielded a maximum imprinting factor of 5.9. A negligible cross-reactivity for DA-AuNP-MIP and DA-AuNP-GQD-MIP sensors was found against glucose, adenovirus epitope, another cTnI epitope, bovine serum albumin (BSA), transferrin, and neuron-specific enolase (NSE). Epitope specificity at various concentrations (10 - 60 nM), concentration-dependent cTnI detection in human serum (0.01 - 10 ng mL-1) and sensor recovery rates (0.1-10 ng mL-1) in human serum were determined with the best-performing sensor (i.e., DA-AuNP-GQD-MIP). The sensor demonstrated very high epitope specificity in comparison to another cTnI epitope as well as excellent detection performances in human serum studies. The newly engineered epitope-mediated electrochemical sensing platform showcases considerable potential for precise and straightforward diagnosis of coronary artery diseases, aiming to materialize a cost-effective Point-of-Care Testing (POCT) system.

Laufer-Meiser K., Alawi M., Böhnke S., Solterbeck C., Schloesser J., Schippers A., Dirksen P., Brüser T., Henkel S., Fuss J., Perner M.

Abstract Chemolithoautotrophic Hydrogenovibrio are ubiquitous and abundant at hydrothermal vents. They can oxidize sulfur, hydrogen or iron, but none are known to use all three energy sources. This ability though would be advantageous in vents hallmarked by highly dynamic environmental conditions. We isolated three Hydrogenovibrio strains from vents along the Indian Ridge, which grow on all three electron donors. We present transcriptomic data from strains grown on iron, hydrogen or thiosulfate with respective oxidation and autotrophic CO2 fixation rates, RubisCO activity, SEM, and EDX. Maximum estimates of one strain’s oxidation potential were 10, 24, and 952 mmol for iron, hydrogen and thiosulfate oxidation and 0.3, 1, and 84 mmol CO2 fixation, respectively, per vent per hour indicating their relevance for element cycling in-situ. Several genes were up- or downregulated depending on the inorganic electron donor provided. Although no known genes of iron-oxidation were detected, upregulated transcripts suggested iron-acquisition and so far unknown iron-oxidation-pathways.

Brandenburg B., Reckleben Y., Griepentrog H.W.

Satellite-sourced data have become a valuable resource for precision agriculture because they provide crucial insights into various parameters that are essential for effective crop management. An array of practical agricultural tools provides comprehensive data for assessing crop biomass, soil conditions, and plant stress symptoms, predicting yields, and performing other functions. Satellite data, when combined with in situ data from different sources, can significantly enhance biomass and yield estimations. The ability of the “PROcesses of radiation, Mass and Energy Transfer” (PROMET) model to predict crop biomass and grain yield and to optimize nitrogen fertilization during the vegetation period was investigated. Field trials were conducted to assess the accuracy and limitations of biomass and yield predictions. The predicted yields were sufficiently accurate on a whole-field basis, and site-specific values showed strong correlations. In additional field trials with different fertilization strategies, the highest yield and nitrogen efficiency were observed for the PROMET-based strategy. Additional experiments with different crops and greater durations are needed to draw a more reliable conclusion.

Akin E., Gharibzahedi S.M., Qiu H., Aliyeva A., Altintas Z.

Hepatitis A virus (HAV) is primarily transmitted through contaminated water. This study developed bioselective polyvinylidene fluoride (PVDF) and polyethersulfone (PES) membranes through chitosan hydrophilic surface modification and immobilization of HAV-specific epitope-imprinted polymers (eIPs) to remove trace levels of HAV. The HAV epitope was imprinted using solid-phase synthesis, involving template immobilization on glass beads, polymerization of monomers, and elution of eIPs. The chosen epitope template from the HAV capsid knob enhanced binding affinity due to its high surface accessibility and hydrophilicity. The average hydrodynamic size, polydispersity index, and zeta-potential of the eIP particles were 232.6 nm, 0.29, and −44.36 mV, respectively, indicating their stability in liquid environments. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopies confirmed chitosan functionalization on PVDF/PES membranes. The fluorescence microscopy confirmed eIP immobilization on the membranes with the Rhodamine B monomer's strong fluorescence intensity. Atomic force microscopy (AFM) monitoring showed that eIP immobilization enlarged pore structures in PVDF membranes and improved chemical phase distribution on PES membrane surfaces. The bare PES and chitosan-functionalized PES/PVDF membranes after eIP immobilization had the lowest and highest root mean square roughness values, respectively. Morphological changes observed via scanning electron microscopy (SEM) revealed that chitosan functionalization smoothed the structures of PVDF and PES membranes by reducing porosity, while eIP immobilization increased surface irregularities with sharper edges and blob-like structures. Functionalized PVDF membranes improved hydrophilicity and filtration efficiency, whereas naturally hydrophilic PES membranes maintained consistent water absorption. Chitosan modification significantly enhanced permeation flux in PVDF and PES membranes by increasing hydrophilicity and improving filtration performance and capacity. Virus concentrations were measured pre- and post-filtration using a UV–visible spectrophotometer to assess the membrane performance. Absorbance at 215 nm showed a linear relationship with HAV virus concentrations from 0.006 to 13.5 IU mL−1, with a quantification limit of 0.36 IU mL−1 under optimal conditions. These new bioselective membranes removed 99.99 % of viruses from water samples, showing robust HAV elimination capabilities and practical potential for drinking water purification.