TY - JOUR A1 - Grebinyk, Anna A1 - Prylutska, Svitlana A1 - Grebinyk, Sergii A1 - Evstigneev, Maxim A1 - Krysiuk, Iryna A1 - Skaterna, Tetiana A1 - Horak, Iryna A1 - Sun, Yanfang A1 - Drobot, Liudmyla A1 - Matyshevska, Olga A1 - Prylutskyy, Yuriy A1 - Ritter, Uwe A1 - Frohme, Marcus T1 - Antitumor efficiency of the natural alkaloid berberine complexed with C60 fullerene in Lewis lung carcinoma in vitro and in vivo JF - Cancer Nanotechnology N2 - Background Berberine (Ber) is a herbal alkaloid with pharmacological activity in general and a high anticancer potency in particular. However, due to its low bioavailability, the difficulty in reaching a target and choosing the right dose, there is a need to improve approaches of Ber use in anticancer therapy. In this study, Ber, noncovalently bound to a carbon nanostructure C60 fullerene (C60) at various molar ratios of the components, was explored against Lewis lung carcinoma (LLC). Methods C60–Ber noncovalent nanocomplexes were synthesized in 1:2, 1:1 and 2:1 molar ratios. Ber release from the nanocomplexes was studied after prolonged incubation at different pH with the liquid chromatography–mass spectrometry analysis of free Ber content. Biological effects of the free and C60-complaxated Ber were studied in vitro towards LLC cells with phase-contrast and fluorescence microscopy, flow cytometry, MTT reduction, caspase activity and wound closure assays. The treatment with C60–Ber nanocomplex was evaluated in vivo with the LLC-tumored C57Bl mice. The mice body weight, tumor size, tumor weight and tumor weight index were assessed for four groups, treated with saline, 15 mg C60/kg, 7.5 mg Ber/kg or 2:1 C60-Ber nanocomplex (15 mg C60/kg, 7.5 mg Ber/kg). Results Ber release from C60–Ber nanocomplexes was promoted with medium acidification. LLC cells treatment with C60–Ber nanocomplexes was followed by enhanced Ber intracellular uptake as compared to free Ber. The cytotoxicity of the studied agents followed the order: free Ber < 1:2 < 1:1 < 2:1 C60–Ber nanocomplex. The potency of cytotoxic effect of 2:1 C60–Ber nanocomplex was confirmed by 21.3-fold decrease of IC50 value (0.8 ± 0.3 µM) compared to IC50 for free Ber (17 ± 2 µM). C60–Ber nanocomplexes induced caspase 3/7 activation and suppressed the migration activity of LLC cells. The therapeutic potency of 2:1 C60–Ber nanocomplex was confirmed in a mouse model of LLC. The tumor growth in the group treated with 2:1 C60–Ber nanocomplex is suppressed by approximately 50% at the end of experiment, while in the tumor-bearing group treated with free Ber no therapeutic effect was detected. Conclusions This study indicates that complexation of natural alkaloid Ber with C60 may be a novel therapeutic strategy against lung carcinoma. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-14749 SN - 1868-6966 VL - 12 SP - 24 PB - BioMed Central ER - TY - JOUR A1 - Goldenberg, Leonid A1 - Köhler, Mathias A1 - Dreyer, Christian T1 - SiO2 Nanoparticles-Acrylate Formulations for Core and Cladding in Planar Optical Waveguides JF - Nanomaterials N2 - A combination of acrylate formulations and SiO2 nanoparticles is investigated with the aim to improve the optical properties of low-refractive index polymers that are used for the fabrication of planar optical waveguides. A decrease in refractive index and also in the thermo-optic coefficient of nanocomposite materials is clearly demonstrated, while some formulations exhibit an increase in the glass transition temperature. The possibility of using these nanocomposite materials to fabricate waveguiding layers with low optical propagation losses at telecommunication wavelengths around 1550 nm is also shown. The nanomaterials can be applied in optical microchips on polymer platforms. KW - fluorinated acrylate KW - silica nanoparticle KW - nanocomposite KW - thermo-optic coefficient KW - optical propagation loss Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-14057 SN - 2079-4991 VL - 11 IS - 5 PB - MDPI ER - TY - JOUR A1 - Bilous, Nataliya A1 - Malko, Vladyslav A1 - Frohme, Marcus A1 - Nechyporenko, Alina T1 - Comparison of CNN-Based Architectures for Detection of Different Object Classes JF - AI N2 - (1) Background: Detecting people and technical objects in various situations, such as natural disasters and warfare, is critical to search and rescue operations and the safety of civilians. A fast and accurate detection of people and equipment can significantly increase the effectiveness of search and rescue missions and provide timely assistance to people. Computer vision and deep learning technologies play a key role in detecting the required objects due to their ability to analyze big volumes of visual data in real-time. (2) Methods: The performance of the neural networks such as You Only Look Once (YOLO) v4-v8, Faster R-CNN, Single Shot MultiBox Detector (SSD), and EfficientDet has been analyzed using COCO2017, SARD, SeaDronesSee, and VisDrone2019 datasets. The main metrics for comparison were mAP, Precision, Recall, F1-Score, and the ability of the neural network to work in real-time. (3) Results: The most important metrics for evaluating the efficiency and performance of models for a given task are accuracy (mAP), F1-Score, and processing speed (FPS). These metrics allow us to evaluate both the accuracy of object recognition and the ability to use the models in real-world environments where high processing speed is important. (4) Conclusion: Although different neural networks perform better on certain types of metrics, YOLO outperforms them on all metrics, showing the best results of mAP-0.88, F1-0.88, and FPS-48, so the focus was on these models. KW - EfficientDet KW - SSD KW - YOLO KW - deep learning KW - neural network KW - object detection Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-19634 VL - 5 IS - 4 SP - 2300 EP - 2320 PB - MDPI ER - TY - JOUR A1 - Przymus, Piotr A1 - Rykaczewski, Krzysztof A1 - Martín-Segura, Adrián A1 - Truu, Jaak A1 - De Santa Pau, Enrique Carrillo A1 - Kolev, Mikhail A1 - Naskinova, Irina A1 - Gruca, Aleksandra A1 - Sampri, Alexia A1 - Frohme, Marcus A1 - Nechyporenko, Alina T1 - Deep Learning in Microbiome Analysis: A Comprehensive Review of Neural Network Models JF - Frontiers in Microbiology N2 - Microbiome research, the study of microbial communities in diverse environments, has seen significant advances due to the integration of deep learning (DL) methods. These computational techniques have become essential for addressing the inherent complexity and high-dimensionality of microbiome data, which consist of different types of omics datasets. Deep learning algorithms have shown remarkable capabilities in pattern recognition, feature extraction, and predictive modeling, enabling researchers to uncover hidden relationships within microbial ecosystems. By automating the detection of functional genes, microbial interactions, and host-microbiome dynamics, DL methods offer unprecedented precision in understanding microbiome composition and its impact on health, disease, and the environment. However, despite their potential, deep learning approaches face significant challenges in microbiome research. Additionally, the biological variability in microbiome datasets requires tailored approaches to ensure robust and generalizable outcomes. As microbiome research continues to generate vast and complex datasets, addressing these challenges will be crucial for advancing microbiological insights and translating them into practical applications with DL. This review provides an overview of different deep learning models in microbiome research, discussing their strengths, practical uses, and implications for future studies. We examine how these models are being applied to solve key problems and highlight potential pathways to overcome current limitations, emphasizing the transformative impact DL could have on the field moving forward. KW - clasiffication KW - clustering KW - deep learning KW - natural language processing KW - microbiome Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-19889 SN - 1664-302X VL - 15 PB - Frontiers ER - TY - JOUR A1 - Radivoievych, Aleksandar A1 - Kolp, Benjamin A1 - Grebinyk, Sergii A1 - Prylutska, Svitlana A1 - Ritter, Uwe A1 - Zolk, Oliver A1 - Glökler, Jörn A1 - Frohme, Marcus A1 - Grebinyk, Anna T1 - Silent Death by Sound: C60 Fullerene Sonodynamic Treatment of Cancer Cells JF - International Journal of Molecular Sciences N2 - The acoustic pressure waves of ultrasound (US) not only penetrate biological tissues deeper than light, but they also generate light emission, termed sonoluminescence. This promoted the idea of its use as an alternative energy source for photosensitizer excitation. Pristine C60 fullerene (C60), an excellent photosensitizer, was explored in the frame of cancer sonodynamic therapy (SDT). For that purpose, we analyzed C60 effects on human cervix carcinoma HeLa cells in combination with a low-intensity US treatment. The time-dependent accumulation of C60 in HeLa cells reached its maximum at 24 h (800 ± 66 ng/106 cells). Half of extranuclear C60 is localized within mitochondria. The efficiency of the C60 nanostructure’s sonoexcitation with 1 MHz US was tested with cell-based assays. A significant proapoptotic sonotoxic effect of C60 was found for HeLa cells. C60′s ability to induce apoptosis of carcinoma cells after sonoexcitation with US provides a promising novel approach for cancer treatment. KW - ultrasound KW - C60 fullerene KW - sonodynamic therapy KW - HeLa cells KW - apoptosis Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-16877 SN - 1422-0067 VL - 24 IS - 2 PB - MDPI ER - TY - JOUR A1 - Villringer, Claus A1 - Steglich, Patrick A1 - Pulwer, Silvio A1 - Schrader, Sigurd A1 - Laufer, Jan T1 - Electro-optical properties of doped polymers with high transparency in the visible wavelength range JF - Optical Materials Express N2 - The electro-optical (EO) properties of poly(methyl methacrylate) and the photopolymer poly(vinyl cinnamate) doped with varying concentrations of the EO chromophore 2-Methyl-4-nitroaniline were measured. The EO polymers were embedded in Fabry-Pérot etalons for the simultaneous determination of the Pockels and Kerr coefficients from measurements of the fringe shift induced by an external electric field. It was found that the host polymer has a significant impact on the EO performance and that the undoped host polymers exhibit a significant Pockels effect. Moreover, the Kerr effect provides a substantial contribution of 27% to the total change of the refractive index at relatively high electric field strengths of E = 91.2 MV m−1. KW - Bragg reflector KW - fiber optic coupler KW - refractive index KW - spatial light modulator KW - transparency KW - tunable filter Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-15480 VL - 11 IS - 11 SP - 3801 EP - 3811 PB - Optica Publishing Group ER - TY - JOUR A1 - Grebinyk, Anna A1 - Prylutska, Svitlana A1 - Grebinyk, Sergii A1 - Ponomarenko, Stanislav A1 - Virych, Pavlo A1 - Chumachenko, Vasyl A1 - Kutsevol, Nataliya A1 - Prylutskyy, Yuriy A1 - Ritter, Uwe A1 - Frohme, Marcus T1 - Drug delivery with a pH-sensitive star-like dextran-graft polyacrylamide copolymer JF - Nanoscale Advances N2 - The development of precision cancer medicine relies on novel formulation strategies for targeted drug delivery to increase the therapeutic outcome. Biocompatible polymer nanoparticles, namely dextran-graft-polyacrylamide (D-g-PAA) copolymers, represent one of the innovative non-invasive approaches for drug delivery applications in cancer therapy. In this study, the star-like D-g-PAA copolymer in anionic form (D-g-PAAan) was developed for pH-triggered targeted drug delivery of the common chemotherapeutic drugs – doxorubicin (Dox) and cisplatin (Cis). The initial D-g-PAA copolymer was synthesized by the radical graft polymerization method, and then alkaline-hydrolyzed to get this polymer in anionic form for further use for drug encapsulation. The acidification of the buffer promoted the release of loaded drugs. D-g-PAAan nanoparticles increased the toxic potential of the drugs against human and mouse lung carcinoma cells (A549 and LLC), but not against normal human lung cells (HEL299). The drug-loaded D-g-PAAan-nanoparticles promoted further oxidative stress and apoptosis induction in LLC cells. D-g-PAAan-nanoparticles improved Dox accumulation and drugs’ toxicity in a 3D LLC multi-cellular spheroid model. The data obtained indicate that the strategy of chemotherapeutic drug encapsulation within the branched D-g-PAAan nanoparticle allows not only to realize pH-triggered drug release but also to potentiate its cytotoxic, prooxidant and proapoptotic effects against lung carcinoma cells. Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-16749 VL - 4 IS - 23 SP - 5077 EP - 5088 PB - Royal Society of Chemistry (RSC) ER - TY - JOUR A1 - Steglich, Patrick A1 - Schasfoort, Richard B. M. T1 - Surface Plasmon Resonance Imaging (SPRi) and Photonic Integrated Circuits (PIC) for COVID-19 Severity Monitoring JF - COVID N2 - Direct optical detection methods such as surface plasmon resonance imaging (SPRi) and photonic-integrated-circuits (PIC)-based biosensors provide a fast label-free detection of COVID-19 antibodies in real-time. Each technology, i.e., SPRi and PIC, has advantages and disadvantages in terms of throughput, miniaturization, multiplexing, system integration, and cost-effective mass production. However, both technologies share similarities in terms of sensing mechanism and both can be used as high-content diagnostics at or near to point of care, where the analyte is not just quantified but comprehensively characterized. This is significant because recent results suggest that not only the antibody concentration of the three isotypes IgM, IgG, and IgA but also the strength of binding (affinity) gives an indication of potential COVID-19 severity. COVID-19 patients with high titers of low affinity antibodies are associated with disease severity. In this perspective, we provide some insights into how SPR and PIC technologies can be effectively combined and complementarily used for a comprehensive COVID-19 severity monitoring. This opens a route toward an immediate therapy decision to provide patients a treatment in an early stage of the infection, which could drastically lowers the risk of a severe disease course. KW - COVID-19 KW - surface plasmon resonance KW - photonic integrated circuit KW - direct optical detection KW - COVID-19 antibody KW - COVID-19 severity KW - pandemic surveillance KW - immunity monitoring Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-16004 SN - 2673-8112 VL - 2 IS - 3 SP - 389 EP - 397 PB - MDPI ER - TY - JOUR A1 - Steglich, Patrick A1 - Lecci, Giulia A1 - Mai, Andreas T1 - Surface Plasmon Resonance (SPR) Spectroscopy and Photonic Integrated Circuit (PIC) Biosensors: A Comparative Review JF - Sensors N2 - Label-free direct-optical biosensors such as surface-plasmon resonance (SPR) spectroscopy has become a gold standard in biochemical analytics in centralized laboratories. Biosensors based on photonic integrated circuits (PIC) are based on the same physical sensing mechanism: evanescent field sensing. PIC-based biosensors can play an important role in healthcare, especially for point-of-care diagnostics, if challenges for a transfer from research laboratory to industrial applications can be overcome. Research is at this threshold, which presents a great opportunity for innovative on-site analyses in the health and environmental sectors. A deeper understanding of the innovative PIC technology is possible by comparing it with the well-established SPR spectroscopy. In this work, we shortly introduce both technologies and reveal similarities and differences. Further, we review some latest advances and compare both technologies in terms of surface functionalization and sensor performance. KW - surface plasmon resonance KW - photonic integrated circuit KW - biosensor KW - surface functionalization KW - label-free detection Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-16018 SN - 1424-8220 VL - 22 IS - 8 PB - MDPI ER - TY - JOUR A1 - Bauer, Joachim A1 - Fursenko, Oksana A1 - Heinrich, Friedhelm A1 - Gutke, Marko A1 - Kornejew, Eckhart A1 - Brödel, Oliver A1 - Dietzel, Birgit A1 - Kaltenbach, Alexander A1 - Burkhardt, Martin A1 - Edling, Matthias A1 - Steglich, Patrick A1 - Herzog, Michael A1 - Schrader, Sigurd T1 - Determination of optical constants and scattering properties of transparent polymers for use in optoelectronics JF - Optical Materials Express N2 - Knowledge of optical constants, i.e. refractive index n and extinction coefficient k, and light scattering properties of optical polymers are required to optimize micro-optics for light-emitting diodes in terms of efficiency, color properties and light distribution. We present here a model-based diagnostic approach to determine the optical properties of polymers, which should be particularly useful in the development of plastics for optical applications. Optical constants and scattering coefficients were obtained from transmission and reflection measurements in a wavelength range from UV to NIR taking into account scattering effects due to rough surfaces and volume inhomogeneity. Based on the models for the dielectric function, the molecular optical transition energies Eg, critical point energies, Urbach energies and exciton transition energies were determined. Rayleigh and Mie scattering model and van de Hulst's anomalous diffraction theory were applied to characterize scattering due to volume inhomogeneities. Scalar diffraction theory was applied to account for surface roughness scattering. Atomic force microscopy with nanomechanical characterization was used to characterize domains in size and shape and to assign optical scattering to a suitable morphological model. The combined optical and mechanical characterization help to improve the qualification of new polymer materials for optical applications. KW - diffraction theory KW - light property KW - optical constant KW - optical material KW - optical property KW - scattering theory Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-15666 VL - 12 IS - 1 SP - 204 EP - 224 PB - Optica Publishing Group ER - TY - JOUR A1 - Radivoievych, Aleksandar A1 - Prylutska, Svitlana A1 - Zolk, Oliver A1 - Ritter, Uwe A1 - Frohme, Marcus A1 - Grebinyk, Anna T1 - Comparison of Sonodynamic Treatment Set-Ups for Cancer Cells with Organic Sonosensitizers and Nanosonosensitizers JF - Pharmaceutics N2 - Cancer sonodynamic therapy (SDT) is the therapeutic strategy of a high-frequency ultrasound (US) combined with a special sonosensitizer that becomes cytotoxic upon US exposure. The growing number of newly discovered sonosensitizers and custom US in vitro treatment solutions push the SDT field into a need for systemic studies and reproducible in vitro experimental set-ups. In the current research, we aimed to compare two of the most used and suitable SDT in vitro set-ups—“sealed well” and “transducer in well”—in one systematic study. We assessed US pressure, intensity, and temperature distribution in wells under US irradiation. Treatment efficacy was evaluated for both set-ups towards cancer cell lines of different origins, treated with two promising sonosensitizer candidates—carbon nanoparticle C60 fullerene (C60) and herbal alkaloid berberine. C60 was found to exhibit higher sonotoxicity toward cancer cells than berberine. The higher efficacy of sonodynamic treatment with a “transducer in well” set-up than a “sealed well” set-up underlined its promising application for SDT in vitro studies. The “transducer in well” set-up is recommended for in vitro US treatment investigations based on its US-field homogeneity and pronounced cellular effects. Moreover, SDT with C60 and berberine could be exploited as a promising combinative approach for cancer treatment. KW - ultrasound KW - C60 fullerene KW - berberine KW - sonodynamic therapy KW - apoptosis Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-18223 SN - 1999-4923 VL - 15 IS - 11 PB - MDPI ER - TY - JOUR A1 - Grytsenko, Kostyantyn A1 - Kolomzarov, Yurii A1 - Lytvyn, Peter A1 - Kondratenko, Olga A1 - Sopinskyy, Mykola A1 - Lebedyeva, Iryna A1 - Niemczyk, Agata A1 - Baranowska, Jolanta A1 - Moszyński, Dariusz A1 - Villringer, Claus A1 - Schrader, Sigurd T1 - Optical and Mechanical Properties of Thin PTFE Films, Deposited from a Gas Phase JF - Macromolecular Materials and Engineering N2 - Thin polytetrafluoroethylene (PTFE) films are produced by deposition from a gas phase by two methods: electron-enhanced vacuum deposition (EVD) and EVD + low-temperature plasma (LTP). Structure, morphology, and composition of the films are studied by IR spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. They are close to the structure of bulk PTFE. The roughness of the films’ surface is changed with gas pressure and LTP power variations. Films are transparent from UV to near-infrared regions. Refractive and extinction indices and their anisotropy are measured by spectral ellipsometry. They are tuned by variations of deposition conditions. Hardness and Young modulus of the films are increased if EVD + low power LTP is used for film deposition. Use of EVD + LTP also increases thermal stability of the films. Contact angle of the films corresponds to the bulk PTFE. The PTFE molecules oriented are preferentially in perpendicular direction to the substrate surface. KW - deposition in vacuum KW - multiphase structure formation KW - optical property KW - plasma KW - polytetrafluoroethylene thin film Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-17587 VL - 308 IS - 6 PB - Wiley ER - TY - JOUR A1 - Radivoievych, Aleksandar A1 - Schnepel, Sophia A1 - Prylutska, Svitlana A1 - Ritter, Uwe A1 - Zolk, Oliver A1 - Frohme, Marcus A1 - Grebinyk, Anna T1 - From 2D to 3D In Vitro World: Sonodynamically-Induced Prooxidant Proapoptotic Effects of C60-Berberine Nanocomplex on Cancer Cells JF - Cancers N2 - Recently, sonodynamic therapy (SDT) has emerged as a promising non-invasive approach for treating cancer by activating sensitizers with ultrasound (US). In this context, we investigated C60 fullerene (C60) as a nanocarrier for the promising drug Berberine (Ber)—both potential aromatic sonosensitizers. The preferential mitochondrial accumulation of C60 and the proapoptotic effects of Ber also make the C60-Berberine nanocomplex (C60-Ber) a good candidate for direct induction of the intrinsic apoptotic cell death under US action. The in vitro research on C60-Ber can provide insights into novel, non-invasive cancer treatments. These findings lead to the development of targeted therapies with reduced side effects, inspire interdisciplinary collaboration, and open new avenues for drug delivery and cancer therapy research. KW - berberine KW - C60 fullerene KW - apoptosis KW - sonodynamic therapy KW - ultrasound Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-19438 VL - 16 IS - 18 ER - TY - JOUR A1 - Demski, Nils Maximilian A1 - Seidlitz, Holger A1 - Kuke, Felix A1 - Dorn, Oliver Niklas A1 - Zoglauer, Janina A1 - Hückstaedt, Tobias A1 - Kamm, Paul Hans A1 - García-Moreno, Francisco A1 - Kremp, Noah A1 - Dreyer, Christian A1 - Oberschmidt, Dirk T1 - Flow-Line-Reducing Tetrahedral Metal Effect Pigments for Injection Molding: A Yield-Rate-Improved Particle Manufacturing Method Based on Soft UVImprint Lithography JF - Polymers N2 - This publication presents an improved manufacturing method for tetrahedral metal effect pigment particles that demonstrates reduced flowlines in injection-molded polymer components compared with conventional platelet-shaped pigment particles. The previously published cold forming process for tetrahedral particles, made entirely from aluminum, faced manufacturing challenges, resulting in a high reject rate due to particle adhesion to the micro-structured mold roller. In contrast, this study introduces a new manufacturing method for tetrahedral particles, now consisting of metallized UV-cured thermoset polymer. These particles, dispersed in amorphous matrix thermoplastics, have shown to maintain their shape during the injection molding process. The manufacturing technique for these novel particles is based on UV imprint lithography, omitting the reject rates compared with the previously presented cold rolling process of tetrahedral full aluminum particles. Thus, the novel manufacturing technique for tetrahedral pigment particles shows increased potential for automation through roll-to-roll manufacturing in the future. KW - flowline KW - injection molding KW - metal effect pigment KW - tetrahedral polymer particle KW - weld line Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-20850 SN - 2073-4360 VL - 17 IS - 19 PB - MDPI ER - TY - JOUR A1 - Lehnert, Martin A1 - Liebchen, Christian A1 - Schiefelbusch, Martin A1 - Bruder, Peter A1 - Harmann, Dennis T1 - Insights into Ridepooling efficiency: A case study analysis using a novel operational performance measure framework JF - Journal of Urban Mobility N2 - The efficiency of demand responsive transport (DRT) services, such as ridepooling, has garnered significant attention across various (simulation) studies. However, a deeper look into the metrics employed to assess system performance exposes notable discrepancies in their utilization. Notably, certain indicators, such as the pooling rate, demonstrate a susceptibility to manipulation based on input parameters, potentially skewing results to give a more favorable impression of service performance. In this paper, we show that, under such circumstances, achieving a fair comparison between study outcomes and with traditional (public) transport modes becomes challenging. In light of these challenges, this study introduces a novel operational performance indicator: Operational System Efficiency (OSE). OSE is tailored to evaluate the operational efficiency of ridepooling systems in a holistic way. In particular, it combines important operational indicators such as detour factor and empty kilometers share, which are considered in numerous analyses. Hereby, OSE is fostering a more equitable assessment of service performance. We applied this methodology and calculated the indicators provided in other studies to two real-world trip datasets from ridepooling services in Berlin and Münster, Germany, and compared the results. Distinct disparities emerge in comparison with conventional efficiency indicators. Consequently, the proposed OSE holds promise for stakeholders, including service providers, public transport companies, and regulatory authorities, as a valuable tool for determining the suitability of a ridepooling service for a given locale relative to other transport modalities, while also providing a transparent assessment of its efficiency. KW - demand responsive transport (DRT) KW - operational system efficiency KW - Pooling index KW - vehicle occupancy Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-20971 SN - 2667-0917 VL - 9 PB - Elsevier ER - TY - JOUR A1 - Ksianzou, Viachaslau A1 - Villringer, Claus A1 - Grytsenko, Kostyantyn A1 - Pekur, Demyd A1 - Lytvyn, Peter A1 - Sopinskyy, Mykola A1 - Lebedyeva, Iryna A1 - Niemczyk, Agata A1 - Baranowska, Jolanta T1 - Structural and Optical Anomalies in Thin Films Grown in a Magnetic Field by Electron-Assisted Vacuum Deposition of PTFE JF - Macromolecular Materials and Engineering N2 - Polytetrafluoroethylene (PTFE) films are deposited in parallel and perpendicular magnetic fields (MF) by electron-enhanced vacuum deposition (EVD) and EVD + low-temperature plasma (LTP) methods. The structure, morphology, and nanomechanical properties of the films are studied by infrared spectroscopy (IRS), atomic force microscopy (AFM), and spectroscopic ellipsometry. The structure of the thicker films is closer to that of bulk PTFE than that of thin films. The films' crystallinity and surface roughness are higher than those deposited without MF. The birefringence of the refractive index (n) of the films deposited in the MF is inverse to the anisotropy of the n of the films deposited without MF. The hardness of the films is close to that of bulk PTFE. KW - birefringence KW - deposition in vacuum KW - morphology KW - plasma KW - thin polytetrafluoroethylene film Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-19712 VL - 310 IS - 3 PB - Wiley ER - TY - JOUR A1 - Roedenbeck, Marc A1 - Herold, Marcel T1 - Personality Profiles in Online Job Advertisements: Applying a Weighted Closed Vocabulary Approach to Identify Generic Profiles and Clusters JF - SAGE Open N2 - On the background of the supplementary applicant-job fit theory, this study tests the application of a weighted closed vocabulary approach as introduced by Ostendorf on a large corpus of online job advertisements (OJA). Therefore, a large dataset of online job advertisements (OJAs) was scraped from a German job portal (N = 151k), and a sample (n = 3,239) was selected based upon Porter’s Value Chain and corresponding job functions. The dataset was pre-processed with techniques of natural language processing, and the predefined words extracted from the OJAs were weighted with the average subject matter expert rating, as offered in the vocabulary of Ostendorf. The results reveal that, first, 0 to 12 words describing personality are used across OJAs, second, that HR, sales, and finance positions show values higher than sample mean (3.22), third, that HR positions show loadings across all dimensions of personality above the sample means (extroversion: 2.32, agreeableness: 3.98, conscientiousness: 4.28, emotional stability: 3.54, openness: 2.0) followed by sales. The job profiles being significantly parallel on equal levels are HR clerk and referee, as well as IT, R&D, and procurement. While conscientiousness is reported to be an important predictor of performance, our study showed only low to average importance in OJAs. KW - LIWC KW - cluster analysis KW - natural language processing KW - online job advertisement KW - personality KW - profile analysis Y1 - 2026 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21282 VL - 16 IS - 1 PB - Sage ER - TY - JOUR A1 - Rothe, Felix A1 - Berger, Jörn A1 - Welker, Pia A1 - Fiebelkorn, Richard A1 - Kupper, Stefan A1 - Kiesel, Denise A1 - Gedat, Egbert A1 - Ohrndorf, Sarah T1 - Fluorescence optical imaging feature selection with machine learning for differential diagnosis of selected rheumatic diseases JF - Frontiers in Medicine N2 - Background and objective: Accurate and fast diagnosis of rheumatic diseases affecting the hands is essential for further treatment decisions. Fluorescence optical imaging (FOI) visualizes inflammation-induced impaired microcirculation by increasing signal intensity, resulting in different image features. This analysis aimed to find specific image features in FOI that might be important for accurately diagnosing different rheumatic diseases. Patients and methods: FOI images of the hands of patients with different types of rheumatic diseases, such as rheumatoid arthritis (RA), osteoarthritis (OA), and connective tissue diseases (CTD), were assessed in a reading of 20 different image features in three phases of the contrast agent dynamics, yielding 60 different features for each patient. The readings were analyzed for mutual differential diagnosis of the three diseases (One-vs-One) and each disease in all data (One-vs-Rest). In the first step, statistical tools and machine-learning-based methods were applied to reveal the importance rankings of the features, that is, to find features that contribute most to the model-based classification. In the second step machine learning with a stepwise increasing number of features was applied, sequentially adding at each step the most crucial remaining feature to extract a minimized subset that yields the highest diagnostic accuracy. Results: In total, n = 605 FOI of both hands were analyzed (n = 235 with RA, n = 229 with OA, and n = 141 with CTD). All classification problems showed maximum accuracy with a reduced set of image features. For RA-vs.-OA, five features were needed for high accuracy. For RA-vs.-CTD ten, OA-vs.-CTD sixteen, RA-vs.-Rest five, OA-vs.-Rest eleven, and CTD-vs-Rest fifteen, features were needed, respectively. For all problems, the final importance ranking of the features with respect to the contrast agent dynamics was determined. Conclusions: With the presented investigations, the set of features in FOI examinations relevant to the differential diagnosis of the selected rheumatic diseases could be remarkably reduced, providing helpful information for the physician. KW - rheumatoid arthritis KW - osteoarthritis KW - connective tissue disease KW - gradient boosting machine KW - forward selection algorithm Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-17922 SN - 2296-858X VL - 10 PB - Frontiers ER - TY - JOUR A1 - Gossing, Wilhelm A1 - Radke, Lars A1 - Biering, Henrik A1 - Diederich, Sven A1 - Mai, Knut A1 - Frohme, Marcus T1 - The ElonginB/C-Cullin5-SOCS-Box-Complex Is a Potential Biomarker for Growth Hormone Disorders JF - Biomedicines N2 - Insulin-like growth factor 1 (IGF-1) is the standard biochemical marker for the diagnosis and treatment control of acromegaly and growth hormone deficiency (GHD). However, its limitations necessitate the screening for new specific and sensitive biomarkers. The elonginB/C-cullin5-SOCS-box-complex (ECS-complex) (an intracellular five-protein complex) is stimulated by circulating growth hormone (GH) and regulates GH receptor levels through a negative feedback loop. It mediates the cells’ sensitivity for GH and therefore, represents a potent new biomarker for those diseases. In this study, individual ECS-complex proteins were measured in whole blood samples of patients with acromegaly (n = 32) or GHD (n = 12) via ELISA and compared to controls. Hierarchical clustering of the results revealed that by combining the three ECS-complex proteins suppressor of cytokine signaling 2 (SOCS2), cullin-5 and ring-box protein 2 (Rbx-2), 93% of patient samples could be separated from controls, despite many patients having a normal IGF-1 or not receiving medical treatment. SOCS2 showed the best individual diagnostic performance with an overall accuracy of 0.93, while the combination of the three proteins correctly identified all patients and controls. This resulted in perfect sensitivity and specificity for all patient groups, which demonstrates potential benefits of the ECS-complex proteins as clinical biomarkers for the diagnostics of GH-related diseases and substantiates their important role in GH metabolism. KW - acromegaly KW - growth hormone deficiency KW - biomarker KW - SOCS2 KW - liquid biopsy KW - pituitary Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-13802 SN - 2227-9059 VL - 9 IS - 2 PB - MDPI ER - TY - JOUR A1 - Zesch, Christoph A1 - Finkelstein, Daniel A1 - Regehly, Martin A1 - Reif, Jürgen A1 - Schrader, Sigurd T1 - Efficient nanosecond barium nitrate Raman laser for the visible spectral range JF - Optics Express N2 - We report on the design and performance of two solid-state Raman lasers, pumped by a frequency-doubled Nd:YAG laser at 532 nm (8 ns FWHM, 10 Hz, up to 10 mJ), that generate either the first or second Stokes radiation with wavelengths of 563 nm and 598 nm. Barium nitrate crystals with a 1 cm² face area and lengths of 3 cm and 5 cm were used as the Raman-active medium in stable semi-spherical resonators. The Raman lasers produced first Stokes and second Stokes pulses, achieving pulse energies up to 2.3 mJ and conversion efficiencies up to 35% (first Stokes, 5 cm crystal) and 21% (second Stokes, 5 cm crystal). The output beams exhibit nearly Gaussian profiles with beam quality factors of M² = 1.67 and M² = 1.83, respectively. The proposed design and characterization demonstrated a Raman laser with high efficiency and superior beam quality. After subsequent frequency doubling, the output appears well dedicated for future differential absorption LiDAR (DIAL) applications. KW - Gaussian beam KW - laser source KW - Nd:YAG laser KW - Raman laser KW - solid state laser KW - ultraviolet laser Y1 - 2026 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21320 VL - 34 IS - 4 SP - 6355 EP - 6363 PB - Optica ER - TY - JOUR A1 - Bauer, Joachim A1 - Heinrich, Friedhelm A1 - Villasmunta, Francesco A1 - Villringer, Claus A1 - Reck, Johanna A1 - Peters, Sven A1 - Treffer, Alexander A1 - Kuhnt, Christian A1 - Marschmeyer, Steffen A1 - Fursenko, Oksana A1 - Stolarek, David A1 - Mai, Andreas A1 - Regehly, Martin T1 - Reflectometric method for measuring residual oxides in through-silicon vias for 3D chip integration JF - Optics Express N2 - A significant aspect of fabricating 3D chip architectures is ensuring proper contact between the different layers of the chip, which often requires removing the underside of isolation layers before filling vias with conductive material. Currently, scanning electron microscopy is the established method for investigating such structures. In this paper, we propose a rapid, non-destructive optical analysis technique for the simultaneous measurement of through-silicon vias (TSV) depths, silicon wafer thickness, and residual oxide thickness. The proposed method utilizes Fourier peak shift analysis (FPSA) of reflectance measurements in the near-infrared (1200 nm—2200 nm) spectral regions. The application of FPSA to representative samples taken from a commercial TSV integration process for MEMS and CMOS fabrication demonstrated good agreement with reference scanning electron microscopy measurements, confirming the feasibility of the method for in-line and in-situ metrology. The results indicate that FPSA has great potential for real-time process monitoring and control during 3D chip manufacturing. KW - effective refractive index KW - Fourier transforms KW - near infrared KW - ray tracing KW - scanning electron microscopy KW - thin film Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-20633 VL - 33 IS - 15 SP - 32175 EP - 32189 PB - Optica ER -