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101.
Sander Bekeschus Abraham Lin Alexander Fridman Kristian Wende Klaus-Dieter Weltmann Vandana Miller 《Plasma Chemistry and Plasma Processing》2018,38(1):1-12
A comparative study of two plasma sources (floating-electrode dielectric barrier discharge, DBD, Drexel University; atmospheric pressure argon plasma jet, kINPen, INP Greifswald) on cancer cell toxicity was performed. Cell culture protocols, cytotoxicity assays, and procedures for assessment of hydrogen peroxide (H2O2) were standardized between both labs. The inhibitory concentration 50 (IC50) and its corresponding H2O2 deposition was determined for both devices. For the DBD, IC50 and H2O2 generation were largely dependent on the total energy input but not pulsing frequency, treatment time, or total number of cells. DBD cytotoxicity could not be replicated by addition of H2O2 alone and was inhibited by larger amounts of liquid present during the treatment. Jet plasma toxicity depended on peroxide generation as well as total cell number and amount of liquid. Thus, the amount of liquid present during plasma treatment in vitro is key in attenuating short-lived species or other physical effects from plasmas. These in vitro results suggest a role of liquids in or on tissues during plasma treatment in a clinical setting. Additionally, we provide a platform for correlation between different plasma sources for a predefined cellular response. 相似文献
102.
Gabriel Harley Klaus-Dieter Kreuer Joachim Maier Lutgard C. De Jonghe 《Journal of Non》2009,355(16-17):932-937
The structure of La-based metaphosphate glasses modified with aliovalent alkaline earth elements (M = Ba, Ca, Sr), with P:(M + La) ratio kept approximately at 3, were analyzed using Raman and IR spectroscopy. Increasing the concentration of the alkaline earths monotonically decreased the glass density and glass transition temperature, and shifted some vibrational modes by as much as 40 wavenumbers. The Raman frequencies of the symmetric POP and the PO vibrations depended on the M/La ratio, but not on the type of alkaline earth addition; however, the type of alkaline earth cation significantly changed the symmetric PO2 vibration. The average cation-oxygen coordination number remained near ~7 except for a slight decrease for high concentrations of Ca and Sr substitutions. The POP/PO2 intensity ratio increased with increasing alkaline earth content. The replacement of divalent elements for trivalent La in a metaphosphate glass structure was partially accommodated by incorporation of protons as charge compensating defects. The protons were found to be in close proximity to the divalent cations. 相似文献
103.
Common Structural Elements in the Chromophore Binding Pocket of the Pfr State of Bathy Phytochromes 下载免费PDF全文
Francisco Velázquez Escobar David Buhrke Norbert Michael Luisa Sauthof Svea Wilkening Neslihan N. Tavraz Johannes Salewski Nicole Frankenberg‐Dinkel Maria Andrea Mroginski Patrick Scheerer Thomas Friedrich Friedrich Siebert Peter Hildebrandt 《Photochemistry and photobiology》2017,93(3):724-732
Phytochromes are bimodal photoreceptors which, upon light absorption by the tetrapyrrole chromophore, can be converted between a red‐absorbing state (Pr) and far‐red‐absorbing state (Pfr). In bacterial phytochromes, either Pr or Pfr are the thermally stable states, thereby constituting the classes of prototypical and bathy phytochromes, respectively. In this work, we have employed vibrational spectroscopies to elucidate the origin of the thermal stability of the Pfr states in bathy phytochromes. Here, we present the first detailed spectroscopic analysis of RpBphP6 (Rhodopseudomas palustris), which together with results obtained for Agp2 (Agrobacterium tumefaciens) and PaBphP (Pseudomonas aeruginosa) allows identifying common structural properties of the Pfr state of bathy phytochromes, which are (1) a homogenous chromophore structure, (2) the protonated ring C propionic side chain of the chromophore and (3) a retarded H/D exchange at the ring D nitrogen. These properties are related to the unique strength of the hydrogen bonding interactions between the ring D N‐H group with the side chain of the conserved Asp194 (PaBphP numbering). As revealed by a comparative analysis of homology models and available crystal structures of Pfr states, these interactions are strengthened by an Arg residue (Arg453) only in bathy but not in prototypical phytochromes. 相似文献
104.
Numerical simulations are performed for multiphase jets in crossflow. The flow solver uses an Eulerian/Lagrangian approach. Turbulence in the gas phase is modeled in the framework of large eddy simulation. The dispersed phase is handled using Lagrangian particle tracking. The model assumptions of solvers for Lagrangian particle tracking are critically assessed for typical flow conditions of spray jets in crossflow. The droplets are assumed to be spherical and isolated. It is shown that several model assumptions are apparently inconsistent in larger portions of the flow field. Firstly, average Weber numbers can be so large that the model assumption to regard droplets as spherical is questionable, not only near the nozzle, but also in the far-field. Secondly, the average droplet spacing can be so low that droplets directly interact with each other, again also in the far-field. Thirdly, the average Stokes numbers in the jet region can be so large that the phase coupling between the dispersed and continuous phase is weak. Some remedies to these deficiencies are proposed. 相似文献
105.
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107.
F. Meissner W. -D. Schmidt-Ott V. Freystein T. Hild E. Runte H. Salewski R. Michaelsen 《Zeitschrift für Physik A Hadrons and Nuclei》1989,332(2):153-156
Theα- and β-decay of the new isotope167W were observed in the reaction of 191 MeV36Ar with136Ba using a helium-jet and a fast tape-transport system. The identification is based on coincidences with tantalum X-rays and excitation function measurements. The measured half-life is 19.9(5) s. A decay scheme comprising 12 levels was constructed from γγ-coincidences. The β-decay is discussed within experimental and calculated level systematics. Alpha-rays with energy 4.55(2) MeV were assigned to167W. 相似文献
108.
Wolf-Diethard Pfeiffer Klaus-Dieter Ahlers Abiodun Falodun Alexander Villinger Peter Langer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):324-332
Abstract Selenoureas were prepared from isoselenocyanates and structurally characterized by spectroscopic methods and by X-ray crystal structure analyses. 相似文献
109.
Dr. Klaus-Dieter Schotte 《Zeitschrift für Physik A Hadrons and Nuclei》1968,212(5):467-476
It is shown that with the help of a transformation method one can investigate both the Suhl and the Nagaoka theory without taking account explicitly of the ordinary scattering potential and that on can still trace all its effects. We further establish the equivalence between the Suhl and the Nagaoka approaches under certain restrictions concerning the solutions of the integral equations. 相似文献
110.