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End date: 2019 × Start date: 2010 × Has files: Yes × Version: publishedVersion × WGL Institute: INP ×

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    Entwicklung eines Plasma-Emissionsdetektors für die Bestimmung von Schwermetall-Spezies für Anwendungen in der Umweltanalytik, Lebensmittel-Qualitätssicherung und Umweltmedizin : Schlussbericht ; (Bewilligungszeitraum: 01.02.2009 - 31.07.2012)
    (Greifswald : Leibniz-Institut für Plasmaforschung und Technologie, 2012) Wolfgang Buscher, Wolfgang Buscher; Ehlbeck, Jörg; Piechotta, Christian
    [no abstract available]
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    Activation of murine immune cells upon co-culture with plasma-treated B16F10 melanoma cells
    (Basel : MDPI, 2019) Rödder, Katrin; Moritz, Juliane; Miller, Vandana; Weltmann, Klaus-Dieter; Metelmann, Hans-Robert; Gandhirajan, Rajesh; Bekeschus, Sander
    Recent advances in melanoma therapy increased median survival in patients. However, death rates are still high, motivating the need of novel avenues in melanoma treatment. Cold physical plasma expels a cocktail of reactive species that have been suggested for cancer treatment. High species concentrations can be used to exploit apoptotic redox signaling pathways in tumor cells. Moreover, an immune-stimulatory role of plasma treatment, as well as plasma-killed tumor cells, was recently proposed, but studies using primary immune cells are scarce. To this end, we investigated the role of plasma-treated murine B16F10 melanoma cells in modulating murine immune cells' activation and marker profile. Melanoma cells exposed to plasma showed reduced metabolic and migratory activity, and an increased release of danger signals (ATP, CXCL1). This led to an altered cytokine profile with interleukin-1β (IL-1β) and CCL4 being significantly increased in plasma-treated mono- and co-cultures with immune cells. In T cells, plasma-treated melanoma cells induced extracellular signal-regulated Kinase (ERK) phosphorylation and increased CD28 expression, suggesting their activation. In monocytes, CD115 expression was elevated as a marker for activation. In summary, here we provide proof of concept that plasma-killed tumor cells are recognized immunologically, and that plasma exerts stimulating effects on immune cells alone. © 2019 by the authors.
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    Comparative studies of low-intensity short-length arcs
    (Praha : Czech Technical University in Prague, Faculty of Electrical Engineering, Department of Physics, 2019) Baeva, M.; Siewert, E.; Uhrlandt, D.
    We present results obtained by two non-equilibrium modelling approaches and experiments on low-intensity short-length arcs in argon at atmospheric pressure. The first one considers a quasi-neutral arc column combined with boundary conditions on the electrodes based on the energy balance in the space-charge sheaths. The second approach applies a unified description over the entire gap and solves the Poisson equation for the self-consistent electric field. The experiments provide the arc voltage.
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    3D analysis of low-voltage gas-filled DC switch using simplified arc model
    (Praha : Czech Technical University in Prague, Faculty of Electrical Engineering, Department of Physics, 2019) Gortschakow, S.; Gonzalez, D.; Yu, S.; Werner, F.
    Electro-magnetic simulations have been used for the visualization of distribution of Lorentz force acting on a DC switching arc in low-voltage contactor. A simplified plasma model (black-box model) was applied for the description of arc conductivity. Arc geometry was gained from the high-speed camera images. Influence of arc position, arc current and of external magnetic field has been studied. Results have been compared with optical observations of the arc dynamics.
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    The HIPPO Transducer YAP and Its Targets CTGF and Cyr61 Drive a Paracrine Signalling in Cold Atmospheric Plasma-Mediated Wound Healing
    (London: Hindawi, 2019) Shome, Debarati; von Woedtke, Thomas; Riedel, Katharina; Masur, Kai
    Reactive species play a pivotal role in orchestrating wound healing responses. They act as secondary messengers and drive redox-signalling pathways that are involved in the homeostatic, inflammatory, proliferative, and remodelling phases of wound healing. The application of Cold Atmospheric Plasma (CAP) to the wound site produces a profusion of short- and long-lived reactive species that have been demonstrated to be effective in promoting wound healing; however, knowledge of the mechanisms underlying CAP-mediated wound healing remains scarce. To address this, an in vitro coculture model was used to study the effects of CAP on wound healing and on paracrine crosstalk between dermal keratinocytes and fibroblasts. Using this coculture model, we observed a stimulatory effect on the migration ability of HaCaT cells that were cocultured with dermal fibroblasts. Additionally, CAP treatment resulted in an upregulation of the HIPPO transcription factor YAP in HaCaTs and fibroblasts. Downstream effectors of the HIPPO signalling pathway (CTGF and Cyr61) were also upregulated in dermal fibroblasts, and the administration of antioxidants could inhibit CAP-mediated wound healing and abrogate the gene expression of the HIPPO downstream effectors. Interestingly, we observed that HaCaT cells exhibited an improved cell migration rate when incubated with CAP-treated fibroblast-conditioned media compared to that observed after incubation with untreated media. An induction of CTGF and Cyr61 secretion was also observed upon CAP treatment in the fibroblast-conditioned media. Finally, exposure to recombinant CTGF and Cyr61 could also significantly improve HaCaT cell migration. In summary, our results validated that CAP activates a regenerative signalling pathway at the onset of wound healing. Additionally, CAP also stimulated a reciprocal communication between dermal fibroblasts and keratinocytes, resulting in improved keratinocyte wound healing in coculture. © 2020 Debarati Shome et al.
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    Analysis of the release characteristics of Cu-treated antimicrobial implant surfaces using atomic absorption spectrometry
    (New York, NY : Hindawi, 2012) Zietz, C.; Fritsche, A.; Finke, B.; Stranak, V.; Haenle, M.; Hippler, R.; Mittelmeier, W.; Bader, R.
    New developments of antimicrobial implant surfaces doped with copper (Cu) ions may minimize the risk of implant-associated infections. However, experimental evaluation of the Cu release is influenced by various test parameters. The aim of our study was to evaluate the Cu release characteristics in vitro according to the storage fluid and surface roughness. Plasma immersion ion implantation of Cu (Cu-PIII) and pulsed magnetron sputtering process of a titanium copper film (Ti-Cu) were applied to titanium alloy (Ti6Al4V) samples with different surface finishing of the implant material (polished, hydroxyapatite and corundum blasted). The samples were submersed into either double-distilled water, human serum, or cell culture medium. Subsequently, the Cu concentration in the supernatant was measured using atomic absorption spectrometry. The test fluid as well as the surface roughness can alter the Cu release significantly, whereby the highest Cu release was determined for samples with corundum-blasted surfaces stored in cell medium.
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    The kINPen—a review on physics and chemistry of the atmospheric pressure plasma jet and its applications
    (Bristol : IOP Publ., 2018-5-16) Reuter, Stephan; von Woedtke, Thomas; Weltmann, Klaus-Dieter
    The kINPen® plasma jet was developed from laboratory prototype to commercially available non-equilibrium cold plasma jet for various applications in materials research, surface treatment and medicine. It has proven to be a valuable plasma source for industry as well as research and commercial use in plasma medicine, leading to very successful therapeutic results and its certification as a medical device. This topical review presents the different kINPen plasma sources available. Diagnostic techniques applied to the kINPen are introduced. The review summarizes the extensive studies of the physics and plasma chemistry of the kINPen performed by research groups across the world, and closes with a brief overview of the main application fields.
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    Lichtquellen für nachhaltige Beleuchtungskonzepte : Schlussbericht zum Teilprojekt 11 im Verbundprojekt: Verlust der Nacht: Ursachen und Folgen künstlicher Beleuchtung für Umwelt, Natur und Mensch ; Projektlaufzeit: 01.05.2010 - 31.12.2013
    (Hannover : Technische Informationsbibliothek, 2014) Uhrlandt, Dirk; Franke, Steffen; Methling, Ralf; Schöpp, Heinz; Barkowski, Karina; Zalach, Jacob
    [no abstract available]
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    Wachstumskern Centifluidic Technologies, Projekt 5.3: Auswahl der Materialien, Beschichtung, Modifikation von Oberflächen : Projekt-Schlussbericht : Berichtslaufzeit: 01.10.2012 bis 31.01.2014
    (Hannover : Technische Informationsbibliothek (TIB), 2015) Polak, Martin
    Das Ziel des Projektes war die plasma-gestützte Schichtabscheidung einerseits zur Erzeugung von superhydrophoben und superhydrophilen Oberflächeneigenschaften und andererseits um die Adhäsion von Proteinen zu verbessern. Um dieses Ziel zu erreichen, wurden Niederdruck- und Atmosphärendruckplasmen zum Einsatz gebracht. Bei den Atmosphärendruckplasmen wurde darüber hinaus Quellen zur lokalen und zur flächigen Oberflächenveredelung untersucht. Sowohl die Erzeugung der superhydrophilen und superhydrophoben Oberflächeneigenschaften als auch die verbesserte Anhaftung von Proteinen konnte im Projekt erfolgreich umgesetzt werden.
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    Spatio-temporal characterization of the multiple current pulse regime of diffuse barrier discharges in helium with nitrogen admixtures
    (Bristol : IOP Publ., 2017-09-20) Bogaczyk, Marc; Tschiersch, Robert; Nemschokmichal, Sebastian; Meichsner, Jürgen
    This work reports on the spatio-temporal characterization of the multiple current pulse regime of diffuse barrier discharges driven by sine-wave feeding voltage at a frequency of 2 kHz in helium with small nitrogen admixtures. The discharge gap of 3 mm is bounded by glass plates on both plane electrodes. Priority is given to the lateral discharge inhomogeneities, underlying volume- and surface-memory effects, and the breakdown mechanism. Therefore, relevant processes in the discharge volume and on the dielectric surfaces were investigated by ICCD camera imaging and optical emission spectroscopy in combination with electrical measurements and surface charge diagnostics using the electro-optic Pockels effect of a bismuth silicon oxide crystal. The number of current pulses per half-cycle of the sine-wave voltage rises with increasing nitrogen admixture to helium due to the predominant role of the Penning ionization. Here, the transition from the first glow-like breakdown to the last Townsend-like breakdown is favored by residual species from the former breakdowns which enhance the secondary electron emission during the pre-phase of the later breakdowns. Moreover, the surface charge measurements reveal that the consecutive breakdowns occur alternately at central and peripheral regions on the electrode surface. These spatial inhomogeneities are conserved by the surface charge memory effect as pointed out by the recalculated spatio-temporal development of the gap voltage.