Library

X
You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Rapid Communication: Regional Variability in DNA Fragmentation After Global Ischemia Evidenced by Combined Histological and Gel Electrophoresis Observations in the Rat Brain (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 61 (1993), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: We have studied whether the delayed cell death induced by transient forebrain ischemia is associated with an inter-nucleosomal cleavage of DNA into oligonucleosome-sized fragments. The integrity of genomic DNA in various brain regions after a 20-min four-vessel ischemia was examined using gel elec-trophoresis. We found typical ladders of oligonucleosomal DNA fragments in the striatum and in the Ammon's horn. In the latter we also often found a random DNA degradation as a smear pattern. These findings were reinforced by a specific in situ labeling of DNA breaks in tissue sections. A dark staining of nuclei was observed in the cell bodies of neurons—in particular in the head of the caudate and in the vulnerable CAl hippocampal area. With biochemical and histological approaches, there was no evidence of DNA degradation in regions that are resistant to the injury. We conclude that the association of multiple mechanisms of cell damage may occur after a global ischemia. The regional variability in DNA fragmentation stresses the importance of using histological approaches in parallel with gel electrophoresis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1993.tb09843.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Electron parametric instabilities of ultraintense laser pulses propagating in plasmas of arbitrary density (1997)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 4 (1997), S. 3358-3368 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The dispersion relation for electron parametric instabilities of a circularly polarized laser wave of arbitrary intensity is established without restrictions on the plasma density. It is obtained in an implicit analytical form and solved numerically. The well-known stimulated Raman scattering, relativistic modulational instability, relativistic filamentation instability, and two-plasmon decay are recovered at low intensity. Their behavior in the ultrarelativistic regime is characterized by a wide extent of the unstable region in the wave vector space, with growth rates equal to a fraction of the laser frequency, and a strong harmonic generation. Particle-in-cell simulations confirm these results and show that the instability leads to a very strong heating of the plasma. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.872494
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Theory and simulation of electronic relativistic parametric instabilities for ultraintense laser pulses propagating in hot plasmas (2001)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 8 (2001), S. 1664-1672 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The dispersion relation for electronic parametric instabilities of a circularly polarized laser wave is solved in the case where the distribution function is supposed to be cold in the transverse direction and to be a linear combination of a cold distribution function and of a Maxwellian in momentum in the longitudinal direction. Only densities below the critical density are considered. It is shown that the longitudinal temperature as expected reduces the growth rate, but that the existence of a hot tail is not sufficient to significantly reduce the instability. It is the bulk of the distribution function that must be heated to efficiently stabilize the system. Another important effect of the heating is to reduce the backscattered component of the instability. An example of a one-dimensional particle simulation performed in the exact conditions of validity of the theory is discussed. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1359744
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Modulational and Raman instabilities in the relativistic regime (1995)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 2 (1995), S. 2807-2814 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A large amplitude electromagnetic wave propagating in a plasma is known to be subject to severe modulational and Raman instabilities. Previous works were devoted to the weakly relativistic limit and applied mainly to a cold underdense plasma. One extends these works to include the fully relativistic limit for a circularly polarized light for which one derives the dispersion relation in a one-dimensional plasma. The characteristics of the instabilities are also calculated in the case where the plasma is classically overdense, with 1〈(ωp/ω0)2〈γ, where ωp is the plasma frequency, ω0 is the laser frequency, and γ is the relativistic factor of an electron in the laser field. Particle-in-cell simulations confirm the results of the numerical solutions of the dispersion relation. For (ωp/ω0)2/γ=0.57 the growth rate can be as large as 0.52ω0. The nonlinear stage of the instability results in a strong heating of the electron distribution function. The theory is further extended to the case of an initially hot plasma, for which the dispersion relation of the instabilities is established. Its analytical solution is given in the case of a low density plasma. Particle-in-cell simulations are used to treat the general case. One observes a strong reduction of the growth rate of the instability, which tends to restore the possibility to propagate relativistic waves in plasmas. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.871178
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Propagation of ultraintense laser pulses through overdense plasma layers (1996)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 3 (1996), S. 2693-2701 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Due to relativistic effects, a large amplitude electromagnetic wave can propagate in a classically overdense plasma with ω2p(approximately-greater-than)ω2(approximately-greater-than)ω2p/γ, where ωp is the plasma frequency, ω the laser frequency, and γ the relativistic factor of an electron in the laser field. Particle-in-cell simulations are used to study the interaction of an ultrahigh intensity laser pulse in normal incidence on a one-dimensional preformed plasma layer. Both electrons and ions dynamics are included. The width of the layer is 10 to 30 μm and the plasma is characterized by (ωp/ω)2=1.5. During the penetration of the electromagnetic wave a large longitudinal electric field is generated. It results in a strong longitudinal heating of electrons which reach relativistic temperatures. This heating further lowers the effective plasma frequency ωp/γ so the layer becomes almost transparent after the plasma crossing by the wave front. Velocity of the wave front, reflection and transmission rates are studied as functions of the incident energy flux, the plasma thickness, and the pulse duration. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.871526
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Modulational instabilities in strongly pumped systems (1993)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 5 (1993), S. 4456-4464 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this paper, results of a set of numerical simulations applicable to the problem of particle acceleration by the beating of high-energy laser waves are presented. The simulations have periodic or open-ended boundary conditions. The growth rates of the parametric instabilities that are present in both situations are identical. In all cases they yield a destruction of the large amplitude plasma wave in a very short time. The amplitude of the saturation level is shown to be strongly dependent on initial conditions. Finally, some results in the term of the evolution of the distribution function of the background plasma in the context of strong turbulence are shown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.860560
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Nonlinear effects and chaotic behavior at plasma resonance (1990)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 2 (1990), S. 907-915 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Resonant absorption of an electromagnetic wave (f=3.5 GHz) in a multipolar discharge (ne0(approximately-equal-to)1011 cm−3) with an adjustable density gradient is studied. The transition from a nonlinear steady-state regime toward a chaotic one, occurring when the pump field or the gradient length is increased, is investigated experimentally and numerically.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.859290
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Parametric instabilities in resonant absorption (1988)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 31 (1988), S. 2602-2614 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The resonant absorption of electromagnetic waves in an inhomogeneous plasma is studied using a 2-D particle code. For the studied flux (Φ〉8×1014 W/cm2), it is shown that it is impossible to separate resonant absorption from parametric instabilities. Effects of these instabilities on the absorption of incident energy and heating of particles are considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.866538
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    The local–global analysis of the stimulated Brillouin scattering in the regime of nonlinear sound waves (1992)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 4 (1992), S. 576-593 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effect of ion sound wave (ISW) nonlinearities on the stimulated Brillouin scattering (SBS) in long plasmas is investigated within the framework of the Korteweg–de Vries–Maxwell equations. The nonlinear evolution of the driven ISW results in the localization of the ion density on a scale shorter than the wavelength (λs) of the resonant ISW satisfying SBS three-wave matching conditions. Since the transverse wave amplitudes vary on a much longer scale, a local–global modeling of SBS is proposed in which this scale separation is exploited. The local part of the procedure includes a solution to the damped KdV equation with periodic boundary conditions and driven by a constant amplitude ponderomotive force. In the global part of the analysis approximate solutions for the transverse waves in long plasmas are constructed using the results from the local part. Particle-in-cell simulations have been performed in order to investigate the importance of kinetic effects for the local model. Numerical results obtained from the solutions to the KdV–Maxwell equations are well approximated by the local–global modeling. They are also compared with the results of a harmonic decomposition approximation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.860256
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Psychological Aspects of Ageing in Man (1965)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Psychology 16 (1965), S. 417-450 
    Details
    ISSN: 0066-4308
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Psychology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.ps.16.020165.002221
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...