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  • 1
    Electronic Resource
    Electronic Resource
    Cauchy system for resolvent of Milne's integral equation with anisotropic scattering (1985)
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 26 (1985), S. 85-88 
    Details
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: It has been shown previously that the resolvent of the inhomogeneous truncated Milne's integral equation with isotropic scattering enables us to reduce dimensionally the above auxiliary equation via Chandrasekhar's X- and Y-functions. In the present paper, extending the above procedure to the case of anisotropic scattering, we show how to use effectively the Bellman–Krein–Sobolev-like formula for the dimensional reduction of the Cauchy system of the source function via the generalized Chandrasekhar X- and Y-functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.526753
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  • 2
    Electronic Resource
    Electronic Resource
    Quenching of flames by magnetic fields (1989)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 65 (1989), S. 1243-1245 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An experiment has been demonstrated to show a phenomenon involving quenching of candle flames using magnetic fields. An electromagnet with a pair of columnar magnetic poles in which inner sidepieces were hollowed out was used. Magnetic fields of 1.5 T at the brim gave a gradient of 50–300 T/m in the direction perpendicular to the pole axis when the distance of the airgap was in a range of 5–10 mm. A candle was burned in the hollowed space between magnetic poles, and candle flames were exposed to magnetic fields. The flames were quenched a few seconds after the onset of field exposures. A model, called a "magnetic curtain,'' was introduced to explain this phenomenon. It is assumed that the magnetic curtain is a wall of air which is formed by magnetic fields. The magnetic curtain, which is also called an "air curtain,'' blocks air flow in and out of the hollowed space. The interception of oxygen by the magnetic curtain quenches flames. The magnetic curtain also presses back flames and other gases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.343016
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  • 3
    Electronic Resource
    Electronic Resource
    Localized stimulation of neural tissues in the brain by means of a paired configuration of time-varying magnetic fields (1988)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 64 (1988), S. 5862-5864 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A method of localized stimulation of the human brain is proposed. The basic idea is to concentrate induced eddy currents locally in the vicinity of a target in the cortex by a pair of coils which are positioned outside the head so that time-varying magnetic fields pass through the head in the opposite directions around a target. The eddy currents induced at the target are expected to flow together, which results in an increased current flow at the target. Spatial distributions of induced eddy currents are calculated in cubical and spherical volume conductor models by a finite element method. The results show that the current vectors make themselves two vortexes which flow together at the target. The current density at the target makes a peak which is higher by 2–3 times than current densities at nontarget regions. The validity of the proposed method is demonstrated by experiments using frog nerve-muscle preparations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.342181
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  • 4
    Electronic Resource
    Electronic Resource
    Quenching of flames by magnetic fields (abstract) (1988)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 64 (1988), S. 6030-6030 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effects of magnetic fields on combustion of alcohol with the aid of platinum catalysis have been studied to simulate in part the oxidation of organic matter in the living body, and it has been found that the combustion reactions are influenced by magnetic fields. It has also been observed that candle flames are pressed down by magnetic fields of higher intensities when flames are exposed to gradient magnetic fields in a range 20–200 T/m under 0.5–1.4 T. Apart from the combustion experiments, flows of carbon dioxide, oxygen, nitrogen, and argon gases were exposed to magnetic fields up to 2.2 T and 300 T/m. The flows of these gases were blocked or disturbed by the magnetic fields. The purpose of the present study is to clarify the mechanisms for the phenomena observed in the experiments of magnetic effects on combustion and gas flow. An electromagnet with a pair of columnar magnetic poles of which inner sidepieces were hollowed out was used. The magnetic fields of 1.5 T at the brim gave a gradient of 50–100 T/m in the direction perpendicular to the pole axis when the distance of the airgap was in a range 5–10 mm. A candle was burned in the hollowed space between magnetic poles, and candle flames were exposed to magnetic fields. The flames were quenched in a few seconds after the onset of field exposures. Oxygen gas as a paramagnetic molecule can be attracted to the magnetic fields of higher intensities. However, under the intensities of magnetic fields concerned, oxygen gases are not concentrated but are aligned so as to make a "wall of oxygen'' or an "air curtain.'' The air curtain, which is also called the "magnetic curtain,'' blocks air flow into and out of the hollowed space. The interception of oxygen by magnetic curtain quenches flames. The magnetic curtain also presses back flames and other gases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.342142
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  • 5
    Electronic Resource
    Electronic Resource
    Theoretical treatment of vapour pressures for liquid metals (1989)
    Springer
    Journal of materials science 8 (1989), S. 857-861 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01730161
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  • 6
    Electronic Resource
    Electronic Resource
    Histochemical and cytochemical demonstration of Ca++-ATPase activity in the stellate cells of the adenohypophysis of the guinea pig (1985)
    Springer
    Histochemistry and cell biology 83 (1985), S. 195-200 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The histo- and cytochemical localization of Ca++-ATPase activity in the adenohypophysis of the guinea pig was studied utilizing a newly developed method (Ando et al. 1981). An intense reaction was observed in the wall of the blood vessels and between non-secretory cells (stellate cells) and endocrine cells of the pars distalis. Under the electron microscope the Ca++-ATPase reaction product was located extracellularly in relation to the plasmalemma of the stellate cells. This reaction was dependent on Ca++ and the substrate, ATP, and reduced by the addition of 0,1 mM quercetin to the standard incubation medium. Preheating of the sections before incubation completely inhibited the enzyme activity. When Mg++ in different concentrations were substituted for Ca++ in the incubation medium the reaction was always reduced. Both Ca++ and Mg++ in the incubation medium also reduced the reaction. The plasmalemma of the endocrine cells contains no demonstrable amount of Ca++-ATPase activity. The function of the Ca++-ATPase activity is discussed in relation to the regulation of the extracellular Ca++ concentration which seems to be important with respect not only to the secretory process of the endocrine cells but also to the metabolism of the adenohypophysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00953983
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  • 7
    Electronic Resource
    Electronic Resource
    Stochastic approach to cauchy system of Chandrasekhar's planetary problem with specular reflector (1988)
    Springer
    Astrophysics and space science 143 (1988), S. 163-173 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In the present paper, assuming that the radiative transfer in turbed slab bounded below by the imperfect specular reflector is the Markovian process, and starting with the modified Chapman-Kolmogorov equation for a uniform monodirectional illumination, we obtained the Riccati-type of the nonlinear integro-differential equation governing the angular distribution of the radiation emergent from the slab. In other words, without solving the transfer equation, the two-point boundary value problem is reduced to an initial-value problem, by which the numerical simulation is readily performed with the aid of the high-speed digital computer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00636764
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  • 8
    Electronic Resource
    Electronic Resource
    Effects of alternating magnetic fields and low-frequency electric currents on human skin blood flow (1986)
    Springer
    Medical & biological engineering & computing 24 (1986), S. 57-61 
    Details
    ISSN: 1741-0444
    Keywords: Alternating magnetic field ; Biological effect ; Eddy current ; Laser Doppler flowmeter ; Sensory receptors ; Skin blood flow ; Vasomotor tone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The influence of alternating magnetic fields on human skin blood flow was investigated. The hands of volunteers were fixed just above an induction heater and the regional skin blood flow of a fingertip was measured by a laser Doppler flowmeter. The hands were exposed to fields with flux densities of 16 mT, 32 mT and 48 mT at a frequency of 3·8 kHz. Two parameters of the laser Doppler blood flow recording were studied: the dynamic and DC components. The dynamic component did not show any particular changes following magnetic stimulation. The DC component showed a rapid decrease in blood flow in the first period after field-on at 48 mT and 32 mT. A pain sensation with muscle contraction was recognised (48 mT and 32 mT). The effect of electrical stimulation on skin blood flow was also investigated. The differences between the magnetic and electrical effects are discussed. The results suggest that the human body responds to magnetic stimulation with an escape reaction which results in an elevated vasoconstrictor tone. The change in microvascular blood flow recorded with the laser Doppler method can probably be explained by the influence of the eddy currents on the sensory receptors of the skin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02441606
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  • 9
    Electronic Resource
    Electronic Resource
    Effect of time-varying magnetic fields on the action potential in lobster giant axon (1986)
    Springer
    Medical & biological engineering & computing 24 (1986), S. 521-526 
    Details
    ISSN: 1741-0444
    Keywords: Action potential ; Biological effects ; Eddy currents ; Giant axon ; Induced EMF ; Magnetic flux density ; Nerve excitation ; Time-varying magnetic fields
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The possible influence of time-varying magnetic fields on action potential in the lobster giant axon was studied. The axon membrane was excited by galvanic stimulation and the action potential was recorded intracellularly with microelectrodes. During the propagation of the action potential along the axon, alternating or pulsed magnetic fields were applied across the middle part of the axon to study whether or not magnetic fields have any effect on parameters such as conduction velocity and refractory period of the nerve fibre and amplitude, duration and shape of the action potentials. No effect on these parameters was observed under different flux densities and frequencies of the magnetic fields. When simulating the conductive properties of tissue surrounding the nerve with the aid of an external conducting loop with a load resistance, action potentials were generated which made it possible to study the threshold value of the induced eddy current for nerve excitation. Based on the results of the experiment, the influence of magnetic flux density, frequency, conductivity, induced EMF and induced eddy current density is discussed, and a method is proposed for estimating the threshold values of magnetic flux density for nerve excitation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02443969
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  • 10
    Electronic Resource
    Electronic Resource
    Cytochemical demonstration of acid phosphatase activity in the pineal organ of the rainbow trout, Salmo gairdneri (1986)
    Springer
    Cell & tissue research 245 (1986), S. 171-176 
    Details
    ISSN: 1432-0878
    Keywords: Pineal organ, Salmo gairdneri ; Cytochemistry ; Acid phosphatase activity ; Lysosomes ; Macrophages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Activity of acid phosphatase (ACP) was investigated cytochemically in the pineal organ of the rainbow trout, Salmo gairdneri. Intense reaction product for ACP activity was observed (1) in lysosomes varying in size and shape and (2) in endoplasmic reticulum associated with the Golgi complex of (i) the pineal photoreceptor and supporting cells, (ii) vascular endothelial cells, and (iii) macrophages inhabiting pineal lumen, parenchymal epithelium and perivascular spaces. This localization of ACP is discussed with particular reference to the capacity for lysosomal digestion in a pineal organ combining photoreceptive and secretory functions, and lacking a blood-brain barrier, as holds true for the pineal of the rainbow trout. Taking advantage of its capacity for endocytotic uptake and lysosomal digestion, the pineal organ of the rainbow trout may serve as a barrier between the blood circulation and the cerebrospinal-fluid compartment. Furthermore, the macrophages may be considered as an essential component in pineal function of fish.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218097
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