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41.
42.
Micha Juszczak Magdalena Kluska Aneta Kosiska Bogna Rudolf Katarzyna Wo
niak 《Molecules (Basel, Switzerland)》2022,27(9)
In these studies, we investigated the antioxidant activity of three ruthenium cyclopentadienyl complexes bearing different imidato ligands: (η5-cyclopentadienyl)Ru(CO)2-N-methoxysuccinimidato (1), (η5-cyclopentadienyl)Ru(CO)2-N-ethoxysuccinimidato (2), and (η5-cyclopentadienyl)Ru(CO)2-N-phthalimidato (3). We studied the effects of ruthenium complexes 1–3 at a low concentration of 50 µM on the viability and the cell cycle of peripheral blood mononuclear cells (PBMCs) and HL-60 leukemic cells exposed to oxidative stress induced by hydrogen peroxide (H2O2). Moreover, we examined the influence of these complexes on DNA oxidative damage, the level of reactive oxygen species (ROS), and superoxide dismutase (SOD) activity. We have observed that ruthenium complexes 1–3 increase the viability of both normal and cancer cells decreased by H2O2 and also alter the HL-60 cell cycle arrested by H2O2 in the sub-G1 phase. In addition, we have shown that ruthenium complexes reduce the levels of ROS and oxidative DNA damage in both cell types. They also restore SOD activity reduced by H2O2. Our results indicate that ruthenium complexes 1–3 bearing succinimidato and phthalimidato ligands have antioxidant activity without cytotoxic effect at low concentrations. For this reason, the ruthenium complexes studied by us should be considered interesting molecules with clinical potential that require further detailed research. 相似文献
43.
J. H. Keller C. M. McKenna J. R. Winnard W. W. Hicks J. E. Hoffman J. R. Kranik 《辐射效应与固体损伤》2013,168(1-4):195-200
A high current-low energy implant system for the processing of semiconductor devices at medium-high dopant levels is described. Criteria for selection and design of ion beam components such as ion beam optics, vacuum requirements and reliability are discussed. Variations in wafer uniformities for within wafer, wafer-to-wafer and run-to-run are presented. 相似文献
44.
45.
We call A ? $ \mathbb{E} $ n cone independent of B ? $ \mathbb{E} $ n , the euclidean n-space, if no a = (a 1,..., a n ) ∈ A equals a linear combination of B \ {a} with non-negative coefficients. If A is cone independent of A we call A a cone independent set. We begin the analysis of this concept for the sets P(n) = {A ? {0, 1} n ? $ \mathbb{E} $ n : A is cone independent} and their maximal cardinalities c(n) ? max{|A| : A ∈ P(n)}. We show that lim n → ∞ $ \frac{{c\left( n \right)}}{{2^n }} $ > $\frac{1}{2}$ , but can't decide whether the limit equals 1. Furthermore, for integers 1 < k < ? ≤ n we prove first results about c n (k, ?) ? max{|A| : A ∈ P n (k, ?)}, where P n (k, ?) = {A : A ? V n k and V n ? is cone independent of A} and V n k equals the set of binary sequences of length n and Hamming weight k. Finding c n (k, ?) is in general a very hard problem with relations to finding Turan numbers. 相似文献
46.
Ahlswede Rudolf Khachatrian Levon H. Mauduit C. Sárközy A. 《Periodica Mathematica Hungarica》2003,46(2):107-118
In earlier papers finite pseudorandom binary sequences were studied, quantitative measures of pseudorandomness of them were
introduced and studied, and large families of “good” pseudorandom sequences were constructed. In certain applications (cryptography)
it is not enough to know that a family of “good” pseudorandom binary sequences is large, it is a more important property if
it has a “rich”, “complex” structure. Correspondingly, the notion of “f-complexity” of a family of binary sequences is introduced. It is shown that the family of “good” pseudorandom binary sequences
constructed earlier is also of high f-complexity. Finally, the cardinality of the smallest family achieving a prescibed f-complexity and multiplicity is estimated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
47.
J. Hubele P. Kreutz J. C. Adloff M. Begemann-Blaich P. Bouissou G. Imme I. Iori G. J. Kunde S. Leray V. Lindenstruth Z. Liu U. Lynen R. J. Meijer U. Milkau A. Moroni W. F. J. Müller C. Ngô C. A. Ogilvie J. Pochodzalla G. Raciti G. Rudolf H. Sann A. Schüttauf W. Seidel L. Stuttge W. Trautmann A. Tucholski 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(3):263-270
We have studied the fragmentation of Au projectiles interacting with targets of C, Al and Cu at an incident energy ofE/A=600 MeV. The employed inverse kinematics allowed a nearly complete detection of projectile fragments with chargeZ≧2. The recorded fragmentation events were sorted according to three observables, the multiplicityM lp of light charged particles, the largest atomic numberZ max within an event, and a new observable,Z bound, representing the sum of the atomic numbersZ of all fragments withZ≧2. Using these observables, the impact parameter dependence of the fragmentation process was investigated. For all three targets, a maximum mean multiplicity of 3 to 4 intermediate mass fragments (IMFs) is observed. The corresponding impact parameters range from central collisions for theC target to increasingly peripheral collisions for the heavier targets. It is found that the correlation between the IMF multiplicity andZ bound, extending from evaporation type processes (largeZ bound) to the total disassembly of the projectile (smallZ bound), is independent of the target nucleus. This universal behaviour may suggest an — at least partial — equilibration of the projectile fragment prior to its decay. 相似文献
48.
G. J. Spühler K. J. Weingarten R. Grange L. Krainer M. Haiml V. Liverini M. Golling S. Schön U. Keller 《Applied physics. B, Lasers and optics》2005,81(1):27-32
We present two novel semiconductor saturable absorber mirror (SESAM) designs which can exhibit more than ten times lower saturation
fluence than classical SESAM devices. Design considerations and characterization data are presented. These devices are particularly
suited for passively mode-locked lasers with ultra-high repetition rates. 相似文献
49.
Vollmer A Jurchescu OD Arfaoui I Salzmann I Palstra TT Rudolf P Niemax J Pflaum J Rabe JP Koch N 《The European physical journal. E, Soft matter》2005,17(3):339-343
We use ultraviolet photoelectron spectroscopy to investigate the effect of oxygen and air exposure on the electronic structure of pentacene single crystals and thin films. It is found that O2 and water do not react noticeably with pentacene, whereas singlet oxygen/ozone readily oxidize the organic compound. Also, we obtain no evidence for considerable p-type doping of pentacene by O2 at low pressure. However, oxygen exposure lowers the hole injection barrier at the interface between Au and pentacene by 0.25 eV, presumably due to a modification of the Au surface properties. 相似文献
50.
J. O. Keller J. L. Ellzey R. W. Pitz I. G. Shepherd J. W. Daily 《Experiments in fluids》1988,6(1):33-43
The reacting two-dimensional plane mixing layer has been studied in two configurations: a rearward facing step and a two-stream mixing layer. Observations have been made of the steady state behavior, and the unsteady behavior when the flow was forced by a specific acoustic frequency. The steady behavior of the mean properties of the reacting flows is similar to that of non-reacting free shear flows except for the global effects of thermodynamic property changes. The structure of these flows is qualitatively similar to that of non-reacting flows. Vortices form by the two-dimensional Kelvin-Helmholtz instability and grow by subharmonic combination until the mixing layer interacts with the walls. Entrainment is dominated by the two-dimensional vortex motion. Three-dimensional instabilities give rise to secondary vortices which are coherent over several Kelvin-Helmholtz structures and dominate the fine scale mixing process. The mixing transition corresponds to a loss of coherence in the layer. Unsteady behavior occurs when there are resonant interactions with the Kelvin-Helmholtz instability or the instability associated with the recirculation vortex in the rearward facing step flow. Modeling efforts are reported which show promise of simulating the essential features of plane mixing layers.A version of this paper was presented at the ASME Winter Annual Meeting of 1984 and printed in AMD-Vol. 66 相似文献