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    Corrigendum: Concepts and characteristics of the 'COST Reference Microplasma Jet' (Journal of Physics D: Applied Physics (2016) 49 (084003) DOI: 10.1088/0022-3727/49/8/084003)
    (Bristol : IOP Publ., 2019) Golda, J.; Held, J.; Redeker, B.; Konkowski, M.; Beijer, P.; Sobota, A.; Kroesen, G.; Braithwaite, N.St.J.; Reuter, S.; Turner, M.M.; Gans, T.; O’Connell, D.; Schulz-von der Gathen, V.
    There is an incorrect representation of the expression for resistances in parallel in equation (1) in section 4.1 'Voltage probe calibration' on page 6. The numerator and denominator in the equation are reversed and should read: I = Uc Rm + Rt/RmRt. Rm is the measuring resistor, Rt the terminating resistor at the oscilloscope and Uc is the voltage drop across Rm induced by the current I. None of the calculations and conclusions of the paper are affected. The authors apologise for any confusion that this transcription error may have caused. © 2018 IOP Publishing Ltd.
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    Concepts and characteristics of the ‘COST Reference Microplasma Jet’
    (Bristol : IOP Publ., 2016) Golda, J.; Held, J.; Redeker, B.; Konkowski, M.; Beijer, P.; Sobota, A.; Kroesen, G.; Braithwaite, N.S.J.; Reuter, S.; Turner, M.M.; Gans, T.; O’Connell, D.; Schulz-von der Gathen, V.
    Biomedical applications of non-equilibrium atmospheric pressure plasmas have attracted intense interest in the past few years. Many plasma sources of diverse design have been proposed for these applications, but the relationship between source characteristics and application performance is not well-understood, and indeed many sources are poorly characterized. This circumstance is an impediment to progress in application development. A reference source with well-understood and highly reproducible characteristics may be an important tool in this context. Researchers around the world should be able to compare the characteristics of their own sources and also their results with this device. In this paper, we describe such a reference source, developed from the simple and robust micro-scaled atmospheric pressure plasma jet (μ-APPJ) concept. This development occurred under the auspices of COST Action MP1101 'Biomedical Applications of Atmospheric Pressure Plasmas'. Gas contamination and power measurement are shown to be major causes of irreproducible results in earlier source designs. These problems are resolved in the reference source by refinement of the mechanical and electrical design and by specifying an operating protocol. These measures are shown to be absolutely necessary for reproducible operation. They include the integration of current and voltage probes into the jet. The usual combination of matching unit and power supply is replaced by an integrated LC power coupling circuit and a 5 W single frequency generator. The design specification and operating protocol for the reference source are being made freely available.
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    Chemical fingerprints of cold physical plasmas – an experimental and computational study using cysteine as tracer compound
    ([London] : Macmillan Publishers Limited, part of Springer Nature, 2018-5-16) Lackmann, J.-W.; Wende, K.; Verlackt, C.; Golda, J.; Volzke, J.; Kogelheide, F.; Held, J.; Bekeschus, S.; Bogaerts, A.; Schulz-von der Gathen, V.; Stapelmann, K.
    Reactive oxygen and nitrogen species released by cold physical plasma are being proposed as effectors in various clinical conditions connected to inflammatory processes. As these plasmas can be tailored in a wide range, models to compare and control their biochemical footprint are desired to infer on the molecular mechanisms underlying the observed effects and to enable the discrimination between different plasma sources. Here, an improved model to trace short-lived reactive species is presented. Using FTIR, high-resolution mass spectrometry, and molecular dynamics computational simulation, covalent modifications of cysteine treated with different plasmas were deciphered and the respective product pattern used to generate a fingerprint of each plasma source. Such, our experimental model allows a fast and reliable grading of the chemical potential of plasmas used for medical purposes. Major reaction products were identified to be cysteine sulfonic acid, cystine, and cysteine fragments. Less-abundant products, such as oxidized cystine derivatives or S-nitrosylated cysteines, were unique to different plasma sources or operating conditions. The data collected point at hydroxyl radicals, atomic O, and singlet oxygen as major contributing species that enable an impact on cellular thiol groups when applying cold plasma in vitro or in vivo.