Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • 1985-1989  (11)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 280 (1988), S. 246-251 
    ISSN: 1432-069X
    Keywords: Retinoids ; Sebum ; Arotinoid ; Hypervitaminosis A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Retinoids are known to modulate sebaceous gland activity in humans and animals. The nonpolar arotinoid Ro 15-0778 [(E)-1,2,3,4-tetrahydro-1,1,4,4-tetramethyl-6-(1-methyl-2-phenylethenyl) naphthalene] does not contain a polar end group and is devoid of the classical retinoid side effects of hypervitaminosis A. The favorable toxicological profile stimulated the evaluation of this arotinoid in animal models of sebum production. In castrated, testosterone-stimulated male rats, Ro 15-0778 is 50 times more potent than 13-cis-retinoic acid in inhibiting the production and subsequent secretion of sebum. The oral ED50 value of Ro 15-0778 is 30μg/kg, while an oral dose of 0.5 mg/kg inhibited sebum secretion nearly 1005. In testosterone-stimulated female rats, Ro 15-0778 inhibits sebum secretion significantly with an oral ED50 of 140 μg/kg and an s.c. ED50 of 75μg/kg. Ro 15-0778 was also evaluated for its ability to prevent testosterone induction of the immature hamster flank organ. The topical ED50 is 0.53 mg/kg and the oral ED50 is 38 mg/kg. This arotinoid is similarly active in mature male hamsters without testosterone treatment. In addition, the retinoid is active topically and orally in reducing the size of the gerbil abdominal sebaceous gland. The compound exhibits no antiandrogenic activity when tested in ventral prostrate and seminal vesicle assays in rats. Additionally, the compound does not have estrogenic activity when tested in the rat uterine weight assay. High doses of Ro 15-0778 in humans did not demonstrate significant sebumsuppressing activity. This study indicates that extra-polation of retinoid data from rodent animal models to activity in human sebaceous glands can not be made with a high degree of certainty. There is a need to develop new, more predictive models for retinoid activity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 65 (1989), S. 879-881 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Within the framework of the sine-Gordon model of a long Josephson junction, we have calculated a threshold value of bias current density which admits capture of a fluxon by an effective potential well generated by a step of inductance in the junction. Along with a kinematic approximation, a nontrivial dynamical correction is found. We have also calculated analytically energy emitted by a fast fluxon moving past the step.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 29 (1988), S. 21-30 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: A dictionary of correspondence is established between the dynamical variables for spin-glass fluid and Yang-Mills plasma. The Lie-algebraic interpretation of these variables is presented for the two theories. The noncanonical Poisson bracket for the Hamiltonian dynamics of an ideal spin glass is shown to be identical to that for the dynamics of a Yang–Mills fluid plasma, although the Hamiltonians differ for the two theories. This Poisson bracket is associated to the dual space of an infinite-dimensional Lie algebra of semidirect-product type.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 29 (1986), S. 986-991 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This paper: (1) provides the Hamiltonian formulation of the hyperbolic system of two-phase flow equations for separated flows including surface tension; (2) shows that equilibrium solutions of this system are critical states of a certain sum of conserved functionals; and (3) determines sufficient conditions for Lyapunov stability of the equilibrium solutions in two dimensions. The method used to establish the Lyapunov stability conditions incorporates recent advances in the Hamiltonian theory of continuum systems.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 29 (1986), S. 49-68 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Lyapunov stability of relativistic ideal fluid and plasma equilibria is studied analytically using the energy-Casimir method. Two- and three-dimensional relativistic equilibria in a fixed bounded domain are investigated within the framework of the macroscopic multifluid plasma model. Linearized Lyapunov stability conditions and stability norms are given, accounting for warm-plasma effects as well as relativistic and electromagnetic effects. The resulting Lyapunov stability conditions are compared to spectral stability analyses for relativistic cold plasmas in various examples and special cases, including (1) non-neutral electron flow in a planar diode and (2) circularly symmetric plasma flow enclosed in a coaxial waveguide. These linearized stability results can be extended readily to nonlinear Lyapunov stability conditions for finite-amplitude perturbations by employing standard convexity arguments for the Lyapunov functions given here. The relativistic stability conditions are shown to reduce either to their nonrelativistic counterparts or to trivial identities in the nonrelativistic limit.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 29 (1986), S. 3889-3891 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This Brief Communication introduces a special relativistic extension of ideal magnetohydrodynamics having anisotropic pressure, and provides its Hamiltonian formulation in a fixed inertial frame. The nonrelativistic limit of this theory recovers the "double adiabatic'' hydromagnetic equations of Chew, Goldberger, and Low [Proc. R. Soc. London Ser. A 236, 112 (1956)]. For isotropic pressure distribution the equations and Hamiltonian structure reduce to the usual theory of relativistic magnetohydrodynamics. The Poisson bracket for the system is not symplectic. Rather, it is dual to a Lie algebra of semidirect-product type.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Fluid dynamics 21 (1986), S. 302-306 
    ISSN: 1573-8507
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Translational and rotational Brownian movement of a spherical particle in a rarefied gas is considered. It is assumed that the particle radius is much less than the free path of the molecules in the gas. The collision integral of the considered particles and the gas molecules is generalized to the case of an arbitrary law of interaction between the molecules and the particle surface, this making it possible to consider the situation when there is no thermodynamic equilibrium between the particles and the gas, in particular, the particle temperature differs from the gas temperature. By expansion with respect to the small parameter — the ratio of the molecule and particle masses — the kinetic equation of the Boltzmann type reduces to the Fokker-Planck equation for the particle distribution function. The coefficients of the equation are calculated in an explicit form for the case of diffuse interaction between the molecules and the particle surface. A dependence of the diffusion coefficients on the ratio of the particle and gas temperatures is obtained.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Fluid dynamics 22 (1987), S. 279-283 
    ISSN: 1573-8507
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract It is shown that for sufficiently large values of the thermal conductivity of the condensed phaseλ' as compared with the thermal conductivity of the vaporλ (λ/λ' ∼ Kn) the effects associated with the presence of a Knudsen layer on the evaporating surface must be taken into account in order to obtain a solution of the problem of a spherical particle in a slow (Re∞, ≪ 1) continuum (Knudsen number Kn ≪ 1) flow of its own vapor. The drag is calculated for various types of boundary conditions on the particle surface.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Letters in mathematical physics 15 (1988), S. 281-287 
    ISSN: 1573-0530
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract The hydrodynamical approximation to an infinite system of one-dimensional identical hard rods interacting through elastic collisions, is shown to be an integrable system possessing a one-parameter family of nonlinear Hamiltonian structures.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Ocean dynamics 38 (1985), S. 43-67 
    ISSN: 1616-7228
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Description / Table of Contents: Zusammenfassung Es werden die Ergebnisse einer Berechnung des Spektrums der Eigenschwingungen, der räumlichen Struktur und der Energieverteilung der M2-Tide im Paläo-Ozean für neuen Perioden des Phanerozoikums diskutiert. Es konnte gezeigt werden: Die Verdichtung der Kontinente führte zu einer Schwächung der halbtätigen und Verstärkung der eintägigen Eigenschwingungen, die Trennung der Kontinente führte dagegen zur Vergrößerung der halbtätigen und Verringerung der ganztägigen Schwingungen. Änderungen in den Resonanzeigenschaften des Weltozeans beruhen auf einer Änderung der räumlichen Struktur der Gezeiten und auf der Entwicklung der Vernichtung der Gezeitenenergie. DAvor nahm die Vernichtung der Gezeitenenergie zuerst ab und dann, beginnend in der Periode zwischen spätem Karbon und frühem Perm, wuchs sie und erreichte ihr Maximum im frühen Kambrium.
    Abstract: Résumé Les résultats d'un calcul du spectre des ondes propres, de la structure spatiale et des caractéristiques énergétiques de l'onde de marée M2 dans le Paleo-ocean sont étudiés pendant neuf périodes du Phanérozoïque. Il a été montré que la densification des continents provoque une atténuation de l'onde semi-diurne et une amplification de l'onde diurne et inversement la séparation des continents contribue à l'amplification de l'onde semi-diurne et à l'affaiblissement de l'onde diurne. Les modifications des propriétés de résonance de l'océan mondial résultent d'un changement de la structure spatiale des marées et de l'évolution de la dissipation de l'énergie des marées. En remontant dans le temps, la dissipation de l'énergie des marées décroît d'abord, puis à partir du début de la période Carbonifère supérieur — Permien inférieur croît et atteint son maximum pendant le Cambrien inférieur.
    Notes: Summary Results of a calculation of the spectrum of eigenoscillations, spatial structure and energy characteristics of the M2-tidal wave in the paleocean for nine periods of the Phanerozoic are discussed. It has been shown that consolidation of the continents causes attenuation of the semi-diurnal and amplification of the diurnal eigenoscillations and vice versa, isolation of the continents contributes to amplification of the semi-diurnal oscillations and attenuation of the diurnal ones. Changes in the resonant properties of the World Ocean result in a reconstruction of spatial structure of the tides and in evolution of the tidal energy dissipation. As it retreats to the past, the tidal energy dissipation first decreases and then, beginning from the period between the Late Carboniferous — Early Permian, increases reaching its maximum in the Early Cambrian.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...