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  • Articles  (177,338)
  • Springer  (177,338)
  • 2020-2020
  • 1970-1974  (177,338)
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  • 101
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    Electronic Resource
    Theory of neural mediation of intraocular dynamics (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 113-148 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Many experimental studies have indicated that the intraocular pressure is subject to mediation by adrenergic mechanisms affecting both the rate of formation of the aqueous humor and the resistance of the pathway through which the aqueous humor flows out of the eye. Thus, for example, the role of adrenergic drugs in glaucoma therapy is well known. How the mediation is accomplished has not been clarified in detail. Several possible mechanisms have been suggested, and all may indeed be involved. The present study is concerned with the basis and mathematical formulation of one of them and the consequences with respect to aqueous dynamics. The analysis leads to expressions for the aqueous outflow resistance and the formation rate, as well as other quantities of interest. The theoretical behavior is shown to compare favorably with the results of infusion studies and various other experiments, and to provide a unified picture of much of the pressure-flow behavior of both the living and the dead eye.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02477031
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  • 102
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    Eighth International Congress of Electroencephalography and Clinical Neurophysiology (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 149-150 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02477032
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  • 103
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    A fit to nerve membrane rectification curves with a double-dipole-layer membrane model (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 151-172 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Following Wei's suggestion that nerve stimulation and conduction properties are due to dipole layers at the two membrane surfaces (Wei, 1969), we have done steady-state electro-diffusion calculations in the constant field approximation for a simple double-dipole-layer model. We are thereby able to quantitatively fit the recent potassium iso-osmotic rectification curves of Gilbert and Ehrenstein for the squid giant axon membrane. For the squid axon membrane in a natural ion environment, only the outside dipole layer is present in the fit to the data.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02476514
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  • 104
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    Geometrical parameters of the individual myocardial fibers (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 205-211 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract In this paper the left ventricle of the heart was considered as a shell of varying thickness. The first and second fundamental forms of the middle surface, of the shell, as well as Euler's theorem were used for deriving expressions giving the length and curvature of the individual myocardial fibers. Recent anatomical studies have shown that the myocardial fibers in the middle of the left ventricular wall follow a course nearly parallel to the horizontal plane (Streeteret al., 1969). In previous papers (Voukydis 1969, 1970) a mathematical description of the curvature and length of the individual myocardial fibers was presented. Unfortunately, both the curvature and the length formulas contained the cotangent of the fiber helix angle, which approaches infinity as the fiber assumes a course parallel to the horizontal plane. Consequently, these two formulas cannot be used for fibers nearly parallel to the horizontal plane. The present paper will give an alternative way for calculating the length and curvature of the individual myocardial fibers, based on the fundamental forms of surface and on Euler's theorem.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02476516
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  • 105
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    Some remarks on the central nervous system (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 231-242 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract It is pointed out that the successes obtained in the mathematical biology of the central nervous system are based mostly on a number of more or less complicated neuronic circuit models, each inventedad hoc for the purpose of explaining a given phenomenon. The individual models remain disconnected from each other, however, and the unity of the CNS is not apparent. (Rashevsky,Mathematical Biophysics, 3rd Edition, Vol. II, 1960. New York, Dover Publications, Inc.) Some “field theories” of the CNS, as for example that of Griffith (Bull. Math. Biophysics,25, 111–120, 1963;27, 187–195, 1965), give more expression to this unity but lose in the explanation of specific phenomena. The present paper starts with the picture thatevery neuron in the brain isdirectly or indirectly affected to some extent byevery other neuron. This leads to a system of equations with a very large number of variables. Such a system can be replaced in the limiting case by an integral equation of the first kind. At least two specific results can be obtained with this approach and suggestions for further improvement are made.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02476519
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  • 106
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    Fiber stress profiles in the left ventricle of the heart during diastole: Effects of distension and hypertrophy (1972)
    Springer
    Bulletin of mathematical biology 34 (1972), S. 379-392 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Pressure-volume and volume-dimensions relationships, obtained from excised dog left ventricles were used for calculating the stresses acting along the longitudinal axis of the individual myocardial fibers. The calculations were based on a set of empirical and theoretical equations. The pressure-volume relationship as well as the volume-dimensions relationships for the excised left ventricle were expressed in the form of empirical equations; the fiber orientation was written as a function of the fiber location within the left ventricular wall; finally, the fiber stress was determined by means of theoretically derived formulas. Simultaneous solutions for the fibers of a meridian cut through the left ventricular myocardial shell were obtained by means of a digital computer and presented in the form of diagrams. The results showed that at low degrees of distension of the left ventricle there are two zones of higher stresses at the equatorial area, one near the epicardium and one near the endocardium. As the distension proceeds under the effect of progressively increasing intraventricular pressure, these two zones become less well defined, whereas a new zone of higher stresses appears near the apex. At high degrees of distension, the ventricle assumes a more spherical shape and the equatorial zones of higher stresses are replaced by zones of lower stresses. Increase in the myocardial mass results in appearance of the equatorial lower stress zones at lower degrees of distension.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02476449
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  • 107
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    A note on open linear systems (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 97-99 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A theorem is given which states a necessary and sufficient condition for the specific activity to be uniform throughout an open compartmental system in the steady state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02461195
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  • 108
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    Introduction to Mathematics for Life Scientists (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 101-102 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02461196
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  • 109
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    A dynamic model of an environmental system withn interacting components andp degrees of freedom (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 91-96 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The nonlinear differential equations of growth proposed by Volterra (1931) are used as the basis for a dynamic model of ann-element system withp specified, terminal conditions andp missing initial conditions. The resulting two-point boundary-value problem can be solved, ifp is not large, by the shooting method used previously by Huddleston (1967). A numerical example withn=4 andp=2 is solved on a digital computer, and some results are presented.
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    URL: http://dx.doi.org/10.1007/BF02461194
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  • 110
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    Use of a heat transfer analogy for a mathematical model of respiratory tract deposition (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 105-116 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Mathematical models predicting the aerosol deposition in the respiratory tract are reviewed. Data in the literature indicated not only that the air flow in the trachea and major bronchi may not be laminar, but also that the entrance effect of the tube or airway has not been considered. A new approach to a mathematical model of respiratory tract deposition, based on the analogy of the heat and mass transfer, is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02458596
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  • 111
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    Isotherms forr species adsorbed at linear polymers with nearest neighbor cooperative interaction (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 117-126 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The equation of the cooperative specific isotherm is derived for the general case ofr species interacting cooperatively at nearest neighboring sites. Explicit expressions for the special casesr=2–5 are given.
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    URL: http://dx.doi.org/10.1007/BF02458597
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  • 112
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    Pseudo-sound generation at atherosclerotic constrictions in arteries (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 143-155 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Sounds and murmurs have long been employed to qualitatively diagnose cardiovascular disease. However, quantitative diagnosis has been hindered by the lack of understanding of the sound generation and transmission mechanisms. Clinical phonoangiographic studies have shown that simple assumptions about low frequency sound transmission through tissue surrounding an artery are inadequate for obtaining meaningful quantitative diagnosis. Therefore, a theory is developed which relates internal turbulent flow in constricted peripheral arteries to the sound observed at the surface of the skin by means of assumptions of similarity and local axial homogeneity of the internal turbulence. It is found that the spectrum of pressure at the wall of the artery is related to the spectrum of the pressure at the surface of the skin by a filtering factor approximately proportional to ω-2. This arises not because of frequency dependent volumetric absorption in the surrounding medium, as with ultrasound, but because of the manner in which stochastic signals add when observed.
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    URL: http://dx.doi.org/10.1007/BF02458599
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  • 113
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    Measuring a mitotic oscillator: The ARC discontinuity (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 171-182 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Mitosis occurs synchronously in up to 108 nuclei in the syncytial plasmodium ofPhysarum polycephalum. Any two phases of the mitotic cycle may be mixed by fusing plasmodial pairs. A topological property of the synchronized phase of the fused pair as a function of parental phases, the arc discontinuity, characterizes the underlying oscillator, and indicates mitosis is controlled by a moderate relaxation oscillator which rotates more rapidly near its singularity than its limit cycle. A model oscillator is briefly described.
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    URL: http://dx.doi.org/10.1007/BF02458601
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  • 114
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    Genetic nets and dissipative structures: An algebraic approach (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 183-196 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Genetic nets represent an attempt to model genome structure. Depending on the interaction dynamics assumed, they can constitute highly non-linear chemical systems having multiple steady states; hence their relevance to the theory of dissipative structures. Their typical size and possible complexity makes it difficult to study them by means of customary analytical techniques based on differential equations. We have therefore considered an algebraic approach derived from regarding the nets as finite-state automata. This view has revealed a surprisingly rich algebraic structure which can be used to investigate problems concerned with the relation between biological structure and function. This algebraic structure is described with particular reference to the genetic nets of Tsanev and Sendov.
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    URL: http://dx.doi.org/10.1007/BF02458602
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  • 115
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    Finite fluctuations and multiple steady states far from equilibrium (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 205-213 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The role of finite fluctuations in transitions between nonequilibrium steady states in nonlinear systems is investigated. Attention is focused on a model biochemical system for which the usual deterministic chemical kinetics predicts a far-from-equilibrium region of multiple steady states. A stochastic approach to chemical kinetics is adopted to study explicitly the effect of fluctuations around the coexisting stable states on a predicted hysteresis in the transition between those states. A numerical solution of the stochastic master equation for the system yields results which differ qualitatively from predictions of the purely macroscopic theory. Possible implications of these results are considered, and several important aspects of the computational scheme are discussed in some detail.
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    URL: http://dx.doi.org/10.1007/BF02458604
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  • 116
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    The global asymptotic stability of prey-predator systems with second-order dissipation (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 215-217 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Models of biological development, evolution and control should take into account that very small numbers of cells or chemicals or individuals eventually grow into stable, large populations. The simplified two-component model used in these studies includes the following: (1) first-order decay; (2) first-order autocatalysis; (3) negative feedback; (4) positive feedback; (5) second-order decay; (6) second-order autocatalysis. A positive definite Lyapunov function is constructed and shown to have a negative definite total derivative. The stationary statex〉0,y〉0, therefore possesses global asymptotic stability. This means that sustained oscillations cannot occur. Another stationary state,x=y=0, is shown to be unstable. This means that infinitesimally small perturbations ofx=y=0 will result in evolution of the variables to the stable stationary state. This result contrasts with that obtained with the Lotka-Volterra model in that small perturbations ofx=y=0 for that model result in sustained, oscillating excursions; the smaller the initial perturbations, the larger these excursions will be. A simulation illustrates that stable populations of 1020 x's andy's can arise from a singlex andy.x grows more or less continuously, buty remains extremely small for 80 per cent of the time interval required for the variables to approach their stable populations.
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    URL: http://dx.doi.org/10.1007/BF02458605
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  • 117
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    Semiconductor theory of ion transport in thin lipid membranes: II. Surface recombination (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 247-264 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Following the theory of surface recombination in semiconductors, we have derived an expression for the rate of ion recombination at the membrane surface. The surface recombination rate is used in the boundary conditions of current flows at the interfaces. Expressions for the ion fluxes are then derived as functions of environmental variables and membrane parameters. Our analysis strongly suggests that the ion flow through a thin lipid membrane consists of two major components: the surface barrier jumping current and the surface recombination current that are controlled decisively by surface barrier height, surface trap density and surface recombination rates. These general formulations are useful not only for the calculation but also for the understanding of ion transport in thin lipid membranes under a variety of experimental conditions. The implications of this theory to biological membranes and its possible extensions are discussed.
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    URL: http://dx.doi.org/10.1007/BF02461327
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  • 118
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    Transport of O2 along a model pathway through the respiratory region of the lung (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 275-303 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A pathway through the system of branching in the respiratory region of the lung is modelled by a circular cylinder, closed at one end, with partitions which define the component respiratory units. In this model the transport of O2 during inspiration, generated by diffusion is compared with that produced by diffusion together with convection and the importance of convection in the respiratory region in promoting oxygen uptake at the alveolar wall is discussed. For this discussion it is only necessary to consider inspiration. The equations are solved numerically for flow rates of 10, 85 and 200 liters/min. O2 uptake at the wall and curves of constant O2 concentration are shown to illustrate the influence of convection. It is found that after a 2 sec inspiration from an O2 tension of 98 mm Hg and a lung volume of 2300 ml, convection is about 12 per cent as important as diffusion at a flow rate of 85 liters/min, whereas at 10 liters/min convection is only about 0.4 per cent as important as diffusion.
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    URL: http://dx.doi.org/10.1007/BF02461329
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  • 119
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    Theoretical relationship between the optimal models of the vascular tree (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 311-323 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Two models of optimal branching structure of the vascular tree are compared. Murray’s minimum work model derived from minimum energy loss due to flow and volume in the duct system is proved to be included as a mathematical group in the authors’ model defined by the minimum volume under determinant pressure, flow and position at the terminals. The problem about heterotypical trees which are identical at the terminal conditions but different in the topological order of branch combinations are discussed, applying the results of analyses on the equivalent duct of uniform terminal pressure trees. It is proved that the minimum work tree has the least energy loss compared with its heterotypical minimum volume trees and is a better model of branching structure of the vascular tree.
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    URL: http://dx.doi.org/10.1007/BF02461331
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  • 120
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    A morphogenetic system matched to a group (1973)
    Springer
    Bulletin of mathematical biology 35 (1973), S. 615-625 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A period of morphogenesis is operationally defined as a system. This period precedes cell differentiation and is axially expressed. Six interacting elements of structure are defined utilizing Spemann and Mangold's heteroplastic transplantation experiments. The system generates thirty-six interactions, given a rule of composition and specific premises. The element set and operation is matched to the symmetric group S3.
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    URL: http://dx.doi.org/10.1007/BF02458366
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  • 121
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    Asymptotic behavior in a deterministic epidemic model (1973)
    Springer
    Bulletin of mathematical biology 35 (1973), S. 607-614 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The effects of a periodic contact rate and of carriers are considered for a generalization of Bailey's simple epidemic model. In this model it is assumed that individuals become susceptible again as soon as they recover from the infection so that a fixed population can be divided into a class of infectives and a class of susceptibles which vary with time. If the contact rate is periodic, then the number of infectives as time approaches infinity either tends to zero or is asymptotically periodic depending on whether the total population size is less than or greater than a threshold value. The behavior for large time of the number of infectives is determined for three modifications of the model which involve carriers.
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  • 122
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    Electron-phonon (trapped photon) coupling and infrared coaxial transmission line theory of energy transport in mitochondria and nerve (1973)
    Springer
    Bulletin of mathematical biology 35 (1973), S. 627-644 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract This paper develops quantitatively for the kinetics of mitochondrial oxidation the implications of the hypothesis that phosphorylation is accomplished by phonons in the mitochondrial solid. The concept is used that the phonon acts like a trapped photon to produce a reverse photocurrent, which inhibits oxidation, in the absence of phonon dissipation due to phosphorylation or uncoupling. The same conceft in reverse is shown to explain qualitatively the generation or membrane potentials in nerve axon. Infrared optical phonons generated in the above processes are expected to have limited mibility, but it is shown that the structure and geometry of the lipid bilayer membrane are well adapted to the rapid and efficient dissemination of this energy throughout the mitochondrion or nerve axoni n the form of infrared electromagnetic waves by a coaxial transmission line mechanism. The mitochondrion may act like an infrared coaxial resonant cavity.
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  • 123
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    Mathematical analysis of the asymptotic behavior of the Leslie population matrix model (1973)
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    Bulletin of mathematical biology 35 (1973), S. 645-661 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract LetL be a Leslie population matrix. Leslie (1945) and others have shown that the matrixL has a leading positive eigenvalueλ 0 and that in general: (1) $$\mathop {\lim }\limits_{t \to \infty } \frac{{L^t X}}{{\lambda _0^t }} = \gamma X_{\lambda _0 } $$ whereX λ 0 is an eigenvector corresponding toλ 0,X is any initial population vector, and γ is a scalar quantity detormined byX. In this article we generalize (1) exhaustively by removing the mild restrictions on the fertility rates which most writers impose. The result is an oscillatory limit of a kind first noted by Bernardelli (1941) and Lewis (1942) and described by Bernardelli as “population waves”. We calculate in terms ofλ 0 and the entries of the matrixL the values of this oscillatory limit as well as its time-independent average over one period. This calculation includes as its leading special case the result of (1), confirming incidentally that γ is nonzero. To stabilize a population, the matrixL must be adjusted so thatλ 0=1. The limits calculated for the oscillatory and non-oscillatory cases then have maximum significance since they represent the limiting population vectors. We discuss a simple scheme for accomplishing stanbilization which yields as a byproduct an easily accessible scalar measure ofL's tendency to promote population growth. The reciprocal of this measure is the familiar net reproduction rate.
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  • 124
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    The Danziger-Elmergreen theory of periodic catatonic schizophrenia (1973)
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    Bulletin of mathematical biology 35 (1973), S. 689-707 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Properties of the solutions of the mathematical model introduced by Danziger and Elmergreen for the study of periodic catatonic schizophrenia are studied, and it is shown that the properties established suggest that the model can be used to study other forms of catatonic schizophrenia besides periodic catatonic schizophrenia.
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  • 125
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    On the stochastic theory of compartments: Solution forn-compartment systems with irreversible, time-dependent transition probabilities (1974)
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    Bulletin of mathematical biology 36 (1974), S. 489-504 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The bivariate distribution of a two-compartment stochastic system with irreversible, time-dependent transition probabilities is obtained for any point in time. The mean and variance of the number of particles in any compartment and the covariance between the number of particles in each of the two compartments are exhibited and compared to existing results. The two-compartment system is then generalized to ann-compartment catenary and to ann-compartment mammillary system. The multivariate distributions of these two systems are obtained under two sets of initial conditions: (1) the initial distribution is known; and (2) the number of particles in each compartment of the system at timet=0 is determined. The moments of these distributions are also produced and compared with existing results.
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    URL: http://dx.doi.org/10.1007/BF02463262
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  • 126
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    Dustbathing as a regulatory mechanism (1974)
    Springer
    Bulletin of mathematical biology 36 (1974), S. 545-553 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Three mathematical models were developed to describe how some species of birds, such as bobwhite quail (Colinus virginianus) regulate the amount of oil on their plumage. The models assume that dustbathing plays a significant role in this regulatory process. They differed primarily in their assumptions about the relationship between oiling and dustbathing behavior. Several experiments were run to check on the implications of the models.
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    URL: http://dx.doi.org/10.1007/BF02463266
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  • 127
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    Observations on the hydrodynamics and swimming motions of mammalian spermatozoa (1974)
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    Bulletin of mathematical biology 36 (1974), S. 555-565 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract An asymptotic solution of the Stokes Flow equations for a self-propelling filament is presented. An explicit expression for the propulsive velocity is obtained for the case of an infinite filament undergoing small amplitude sinusoidal motions. The asymptotic solution is then used to obtain drag coefficients to be used in a simpler approximate analysis which can be applied to experimentally observed motions.
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  • 128
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    Stochastic theory of compartments: One and two compartment systems (1974)
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    Bulletin of mathematical biology 36 (1974), S. 577-587 
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    Notes: Abstract Previous work on compartmental systems is generalized (i) to allow the particles present at time zero to have a different lifetime distribution than those which arrive after time zero, and (ii) to allow a particle which enters the system at timet to have a lifetime distribution which is a function oft but is otherwise quite general. The one and two compartment models are analyzed under the above conditions and compared to previous results of Thakuret al. (1974), Purdue (1974) and Cardenas and Matis (1974). Finally, some results for the two compartment, reversible system are given. The analysis used is a blend of direct random variable and queueing theoretic techniques.
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    Bounds on the total particle number for species governed by reaction-diffusion equations in the infinite spatial domain (1974)
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    Bulletin of mathematical biology 36 (1974), S. 589-593 
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    Notes: Abstract Differential inequality methods are developed for establishing upper and lower bounds on the total particle numberN(t)=∫θ(x,t) d3 x associated with solutions to nonlinear reaction-diffusion equations of the form ∂θ/∂t=D∇2θ+fθ-gθ n+1 , whereD(〉0),n(〉0),f andg are constant parameters. If finite in a neighborhood oft=0,N(t) is bounded below for allt≥0 by a certain derived function oft for equations withg≥0. An upper bound onN(t) is obtained for equations withn=1,f〈0 andg〈0. These results provide general preservation and extinction criteria for the total particle number.
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    A neuron field theory: Mathematical approaches to the problem of large numbers of interacting nerve cells (1973)
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    Bulletin of mathematical biology 35 (1973), S. 345-357 
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    Notes: Abstract A field theoretical approach to the problem of continuously distributed and simultaneously active nerve cells is presented, starting with a differential-integral field equation of the form $$\frac{\partial }{{\partial t}}\psi (r,t) = H\psi (r,t) + F(r,t)$$ which relates the field ψ to its inhibitory and excitatory sourcesF by means of the field operatorH. General solutions are represented with the aid of Green's functions. The Green's function, giving the response of the system to a very short point stimulation, is calculated in the absence of interaction between neurons and for a special case of non-local interaction. Possible applications of the theory are demonstrated for receptive fields and neuronal mechanisms in the vertebrate retina.
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    Some proposals in cardiac muscle mechanics and energetics (1973)
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    Bulletin of mathematical biology 35 (1973), S. 375-399 
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    Notes: Abstract Based on A. V. Hill's three-component model, mechanical properties of the contractile element (CE), such as velocity and tension, were determined as muscle shortening and loads in quick-release or afterloaded isotonic contraction. The method is applicable for studying cardiac mechanics, to obtain force-velocity data of the same CE length at varous afterloads. Analysis of the energetics of cardiac muscle was based on simulation studies of cardiac mechanics (Wong 1971, 1972). By proper derivation, the conventional contractile element work (CEW) was found to be a minor energy determinant. The tension-time integral and tension-independent heat (Ricchiuti and Gibbs, 1965) represent energy utilization for activation and maintenance of tension, the primary energy determinant.
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    The effect of the torso boundary in electrocardiography (1973)
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    Bulletin of mathematical biology 35 (1973), S. 401-405 
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    Notes: Abstract This paper outlines and contrasts three different (external) “infinite medium” potential fields which may be obtained (in principle) from known geometry, conductivities, and bounded medium torso potentials. Their electrocardiographic implications are considered.
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    An attitude to nucleic acid models (1973)
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    Bulletin of mathematical biology 35 (1973), S. 407-409 
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    Nucleic acid structure (1973)
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    Bulletin of mathematical biology 35 (1973), S. 411-413 
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    Passive transfer of low-molecular nonelectrolytes across deformable semipermeable membranes—I: Equations of convective-diffusion transfer of nonelectrolytes across deformable membranes of large curvature (1974)
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    Bulletin of mathematical biology 36 (1974), S. 365-377 
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    Notes: Abstract The passive transfer of a low-molecular nonelectrolytes mixture across a semipermeable deformable membrane of large curvature is considered. The equations obtained here make it possible to describe the concentration of species redistribution and the change of the membrane shape.
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    A new model for interacting populations—II: Principle of competitive exclusion (1974)
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    Bulletin of mathematical biology 36 (1974), S. 355-364 
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    Notes: Abstract The principle of competitive exclusion is investigated within the framework of the solvable model proposed earlier for two-species systems. The results elucidate the recent controversy over the interpretation of experimental data onDrosophila equilibrium. It is shown that the necessary and sufficient conditions for stable coexistence of competing species is that the product of intraspecific rate constants be greater than the product of interspecific rate constants. Inequalities between rate constants for the occurrence of stable equilibriumbelow andabove the line joining single species equilibria are derived. The availability of larger domain of coexistence suggests that the model presented here has the potential to accommodate a wider class of phenomena than the Gause—Volterra model according to which coexistence is possible only above the line of single species equilibrium.
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    Théorie chromosimique de l'inbreeding: Modèle probabiliste (1974)
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    Bulletin of mathematical biology 36 (1974), S. 417-434 
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    Notes: Abstract A molecular theory of inbreeding involving interactions between zones of gametic recognition (ZRG) localized on the chromosomal sets of male and female gametes is developed. This theory accounts for inbreeding effects and heterosis and raises the problem of control of embryonic development and the biological validity of the inbreeding coefficient. The mathematical analysis of this interaction system with sib matings permits the estimation of viability depression in inbred organisms. The biological validity of the model is discussed.
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    On the probability of reaching a threshold in a stochastic mammillary system (1974)
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    Bulletin of mathematical biology 36 (1974), S. 445-454 
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    Notes: Abstract The multivariate distribution over time of a particular stochastic mammillary compartmental model is obtained for any point in time. The maximum expectation of the peripheral compartments is then derived and used to determine lower bounds on the probability that the maximum of the peripheral compartments reaches any arbitrary threshold level. A bound on the probability is illustrated by an example and some of its implications are explored.
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    Dynamics of populations ofBiomphalaria glabrata and the von forerster equation (1974)
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    Bulletin of mathematical biology 36 (1974), S. 29-37 
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    Notes: Abstract Changes in time of populations ofBiomphalaria glabrata due to changes in the rate of infection bySchistosoma mansomi are investigated. This is done by applying Von Foerster equations with boundary conditions derived from experiment. The resulting equation is solved in some simplified cases and applications of the formalism to ecological problems is suggested.
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    Electrically induced phase transitions via the dipole model in excitable membranes (1974)
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    Bulletin of mathematical biology 36 (1974), S. 17-28 
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    Notes: Abstract Calculations based upon the membrane dipole model have been carried out and indicate the possibility of cooperative behavior during the membrane excitation process. An explicit expression is obtained for the critical electric field,E, which must be present to initiate the cooperative structural transition assumed to occur during membrane excitation. An hypothesis concerning the occurrence of two distinct phase transitions in the membrane resulting in the rapid influx of sodium ions and sodium ion inactivation, respectively, is presented.
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    A note on the shape of the erythrocyte (1974)
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    Bulletin of mathematical biology 36 (1974), S. 55-58 
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    Notes: Abstract Variational calculus is used to derive an equation for the shape of the cross section of a human red blood cell, the objective being the maximization of the surface area/volume ratio. Comparison to previous work is presented.
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    An intergral method for the analysis of flow in arterial stenoses (1974)
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    Bulletin of mathematical biology 36 (1974), S. 39-53 
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    Notes: Abstract An approximate solution is presented to the problem of incompressible flow through an axisymmetric constriction. The geometry is intended to simulate an arterial stenosis, and the solution is applicable to both mild and severe stenoses for Reynolds numbers below transition. Theoretical results obtained for specific geometries are given for the velocity distribution, pressure drop, wall shearing stress, and separation phenomena. These results reveal the significant alterations in flow caused by a stenosis. Experiments using model stenoses are described and compared with the theoretical results. Theoretical predictions of pressure drop and separation characteristics are in reasonably good agreement with the experimental observations.
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    Matematicheskie problemy v biologii (1974)
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    Bulletin of mathematical biology 36 (1974), S. 615-616 
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    The University of Texas Health Science Center at Houston, Division of Continuing Education and The Region V of IEEE announces Eleventh Symposium on Biomathematics and Computer Science in the Life Sciences (1974)
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    Bulletin of mathematical biology 36 (1974), S. 617-617 
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    The simulation of multi-neurone networks: Modelling of the lateral inhibition of the eye and the generation of respiratory rhythm (1974)
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    Bulletin of mathematical biology 36 (1974), S. 77-89 
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    Notes: Abstract We describe a model of a single neurone, and a method of interconnecting such neurone models suitable for multi-neurone network simulations on a digital computer. Two simulations are described; the lateral inhibition in the eye of the Limulus and the generation of respiratory rhythm in the brain stem of the cat.
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    Pulse velocities in cylindrical, tapered and curved anisotropic elastic arteries (1974)
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    Bulletin of mathematical biology 36 (1974), S. 103-103 
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    Interaction of peristaltic motion with Poiseuille flow (1974)
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    Bulletin of mathematical biology 36 (1974), S. 127-141 
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    Notes: Abstract The effect of Poiseuille flow on peristaltic transport has been investigated in a two-dimensional mathematical model of peristalsis for the case when the wall of the channel executes a sinusoidal motion of small amplitude. Closed-form solutions have been obtained for limiting values of Reynolds number and the Poiseuille flow parameter, while the method of Frobenius series solution has been used for the general case. It is found that the mean flow reversal is strongly dependent on the Poiseuille flow. The position of flow reversal may change drastically from the center of the channel to the boundaries. Numberical results are reported for various values of the physical parameters of interest.
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    Enzyme kinetics in cells (1974)
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    Bulletin of mathematical biology 36 (1974), S. 157-169 
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    Notes: Abstract Classical enzymology ignores the role which cellular membranes may play in regulating reaction kineticsin vivo. The correct description of cellular metabolic processes must derive from a mass balance equation for each reacting species. An elementary mathematical model, called the “continuous flow stirred tank reactor” in the chemical engineering literature, has been applied to Michaelis-Menten kinetics, substrate inhibition kinetics, and kinetics involving hydrogen ion as a byproduct. A number of remarkable phenomena, including multiple stationary states, threshold effects, temporal patterns, homeostatic regulation, amplification, and irreversible differentiation can result. Predictions of the model are in qualitative accord with experimental and theoretical studies of insolubilized enzymes, which are conventionally modeled by a more difficult mathematical formalism.
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    Stability and enzyme separation: Integral representation of the solutions (1974)
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    Bulletin of mathematical biology 36 (1974), S. 197-203 
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    Notes: Abstract Two enzymes, cross-coupled through their respective products, are membrane-bound and thereby separated from each other. The cross-coupling is of opposite character and diffusion limited, i.e. an activation-inhibition couple with a diffusion-induced time-lag. In this paper an integral representation for the solutions of the dynamic equations is developed using the Green's function technique, and an application to morphological changes in the mitochrondrion is discussed.
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    Stochastic kinetic models for small irreversible systems (1974)
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    Bulletin of mathematical biology 36 (1974), S. 219-227 
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    Notes: Abstract The probability distribution of the process level is derived for a general class of irreversible reaction systems. A method of approximating the mean and variance of the process level is developed and shown to be more accurate for small irreversible systems than other approximations used in the stochastic approach to kinetics.
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    Semiconductor theory of ion transport in thin lipid membranes: I. Potential and field distributions (1974)
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    Bulletin of mathematical biology 36 (1974), S. 229-246 
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    Notes: Abstract In the theory as presented in this paper and the following one, we shall attempt to apply the semiconductor principles and methods to the study of ion transport in thin lipid membranes. Detailed formulations are given on the potential energy barriers at the interfaces, voltage drops in the polar and non-polar regions, and potential and field distributions in the diffuse double layer and within a charged membrane. These results will be used mainly as the boundary conditions for the solution of ion flow as to be given in the following paper. The analysis clearly indicates that the ion transport is interface-limited and is profoundly influenced by the presence of surface charges. An explanation of Na+ extrusion in nerve membrane is given based on the field distribution analysis. The theory also suggests that the “membrane potential” depends mainly on surface charges but not necessarily on ion permeation through the membrane.
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    Flagellar elongation as a moving boundary problem (1974)
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    Bulletin of mathematical biology 36 (1974), S. 265-273 
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    Notes: Abstract Movement of a proposed controlling factor along the growing flagellum is considered as a special case of one-dimensional diffusion with a moving boundary. Flagellar elongation, which involves polymerization of the building units at the distal tip, is viewed as taking place in a series of steps. The concentration of the controlling factor at the tip is computed as a function of the distance of the tip from the base, and the time between polymerization reactions. It is proposed that the concentration of this factor at the tip is responsible for regulating the flagellar growth rate and final length.
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    Stochastic theory of compartments (1974)
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    Bulletin of mathematical biology 36 (1974), S. 305-309 
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    Notes: Abstract The stochastic model of a compartment developed by Thakur, Rescigno and Schafer is discussed without using generating functions. The behavior of the mean and variance of the number of particles present as a function of time is also discussed. We also allow both the input and output to be time dependent.
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    A new model for interacting populations—I: Two-species systems (1974)
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    Bulletin of mathematical biology 36 (1974), S. 347-353 
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    Notes: Abstract The exact solvable model presented here describes two interacting species whose populations oscillate periodically in time in the absence of self-interaction and attain saturation with fluctuations if self-interactions are included. While sharing broad features of the classical Volterra system, the model proposed here has the advantage of possessing exact solutions. The model thus provides a testing ground for general principles employed in the study of dynamics of populations.
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    The influence of noninstantaneous mixing on the measurement of fluxes of solute and water across a biological membrane (1970)
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    Bulletin of mathematical biology 32 (1970), S. 1-24 
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    Notes: Abstract The usual method of tracer analysis for calculating the flow across a biological membrance is based on the assumption that the compartments on either side are well-stirred. Thus, the validity of the rate of flow determination is questionable for cases where the distribution of tracer is not homogeneous. In this study, a mathematical model is developed for the purpose of estimating the effect of slow mixing on the calculation of the flow rate. The model is applied to the measurement of the rate of flow of aqueous humor through the living eye by use of a fluorescent dye as a tracer. A transit time of several minutes for the passage of fluorescein through the posterior chamber and an extended period of nonuniform distribution of fluorescein in the anterior chamber was observed. The effect of slow mixing on the calculated flow rate is compared to rates derived from equations based on the assumption of rapid mixing. Aqueous flow rates determined by the two methods were found to agree to within ≈20%.
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    The dispersion of indicator in the cardio-pulmonary system (1970)
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    Bulletin of mathematical biology 32 (1970), S. 25-43 
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    Notes: Abstract This paper presents a three-parameter model of the mechanism of dispersion of an indicator in the cardio-pulmonary system, based on the postulates that this dispersion can be described by the one-dimensional diffusion equation and that dispersion continues past the sampling site. The model is tested using indicator dilution curves obtained from dogs, and the coefficient of diffusion is thus measured. It is found that this coefficient increases in magnitude non-linearly with increasing blood speed.
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    The effect of distension of the left ventricle of the heart on the length of the individual myocardial fibers (1970)
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    Bulletin of mathematical biology 32 (1970), S. 45-58 
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    Notes: Abstract Based on the ellipsoid model of the left ventricle and the helicoidal course of the left ventricular myocardial fibers, a theory has been developed for calculating the length of the individual myocardial fibers. Numerical solutions of the final equation show that when the left ventricle is distended, the increase in length of the myocardial fibers is not uniform throughout the thickness of the myocardial wall. It was shown that with increasing dimensions of the left ventricle, the distension of the myocardial fibers becomes smaller as one advances from the endocardium to the middle layer of fibers, whereas it increases as one advances from the middle layer to the epicardial layer. The mechanism by which this effect is brought about as well as its physiological implications are discussed.
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    The gas washout determination under a symmetry assumption (1970)
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    Bulletin of mathematical biology 32 (1970), S. 59-63 
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    Notes: Abstract In an open circuit gas washout determination the output of test substance is shown to be of the form ∑ i=0 ∞ A i λ i k on thekth expiration whereA i 〉0,i=1,2,... and 1 〉 λ1 ≥ λ2...≥ 0 provided the transition from inspiration to expiration has certain symmetry properties with the transition from expiration to inspiration. In general, no direct physical interpretation such as volume for theA t ’s or fraction of retained gas on expiration for the λ i is justified.
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    Mathematical biology of automobile driving IV (1970)
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    Bulletin of mathematical biology 32 (1970), S. 71-78 
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    Notes: Abstract Previous studies by this author of the mathematical biology of automobile driving have emphasized only the biological aspects, except for such mechanical factors as the size of the car. Otherwise, the ideal case of an inertialess car was considered. In this paper the first step is made toward introducing the effects of the mass of the car and the side-slip of the tires when the direction of driving is even slightly altered and combining these with the previously studied biological aspects. Some tentative comparisons with available data are made.
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    Relaxation methods for the determination of drug receptor affinities (1970)
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    Bulletin of mathematical biology 32 (1970), S. 65-69 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract According to the occupation theory of drug receptor interaction, the response is a functionf of the number of receptors occupied by drug molecules. Considerable controversy exists regarding assumptions about this function. Without knowledge of the nature of the function, it is not possible to determine directly the rate constants, and hence the affinity constant, in the reaction between the receptor and an agonist drug. Instead, indirect determinations involving the use of antagonists have been employed, limiting the determination of affinity to those agents for which specific antagonists exist. The present paper discusses a method for the direct determination of affinity of an agonist drug. It is a “relaxation method,” i.e., the equilibrium is perturbed and the kinetics of the restoration process are studied. Assuming only thatf is non-decreasing and approximately linear over a limited domain of concentrations, it is shown that the change in response obeys first order kinetics, permitting a determination of the rate constants from the time course of the restoration process.
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    A remark on the course of development of organismic sets (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 79-81 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The basic postulate la, which governs the development of organismic sets, introduced previously (Bulletin of Mathematical Biophysics,31, 159–198, 1969), is generalized so as to contain also the rates of changes of the number and variety of differentQ-relations which determine an organismic set. It is thus brought closer to the Lagrangian principle in physics. It is pointed out that the postulate also provides a criterion of stability of an organismic set.
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    In-vivo estimations of the nonlinear pressure-volume relationship of the aorta and instantaneous left ventricular volume (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 155-172 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A method is presented in this paper for the in-vivo estimation of the nonlinear pressure-volume relationship of the human aorta. The method is based on nonlinear elastic reservoir theory and utilizes clinical data that can be obtained with a high degree of accuracy, namely stroke volume, end diastolic ventricular volume and aortic pressure trace data. The computational procedure is described and then carried out for six cardiac patients. A method for the estimation of instantaneous left ventricular volume during the ejection period based on the considered nonlinear elastic reservoir theory is also presented. The method is applied for the six cardiac patients cited and the results compared with those obtained for the same subjects by a method of estimation based on linear elastic reservoir theory described in a previous paper by the author (1969).
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    The application of the minimal energy hypothesis to a casson fluid (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 249-262 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Deakin (1967b) suggested that flow of blood might obey a law of minimal energy dissipation. The present paper presents a simpler derivation of Deakin’s equations pointing out several previously unrecognized features. It is shown that these equations are unlikely to be applicable. In particular, the solution obtained by Deakin and Jones (1968) does not yield a true minimum for energy dissipation. The solution for which energy dissipation is actually minimized is shown to possess features which render it unlikely to apply to a real flow.
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    Some remarks on the Kedem-Katchalsky equations for non-electrolytes (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 237-247 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The Kedem-Katchalsky equation for the flow of a non-electrolyte through a homogeneous membrane is shown to be a first order expansion of an exact integral of the Spiegler-Bearman-Kirkwood frictional equations under the assumption that the partial frictional coefficients, ζ ij , are concentration independent. The equations are solved in terms of volume flow; there are no water-to-volume flow correction terms for the permeability, ω, or the reflection coefficient, σ. The precision of the expansion depends upon the magnitude of the water flow. The frictional coefficientsf sm andf sw are given as functions of the experimentally determined parameters ω and σ; the frictions, are shown to be independent ofL p .
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    On the average cellular volume in synchronized cell populations (1970)
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    Bulletin of mathematical biology 32 (1970), S. 459-473 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract As was done by Sinclair and Ross (1969(, we consider a cellular population that consists initially (at time zero) ofN 0 newborn cells, all with the same volumev o. It is assumed that the occurrence of cell division is determined only by a cell’s age, and not by its volume. The frequency function of interdivision times, τ, is denoted byf(τ). If cell death is negligible, the expected number of cells,N(t), will increase according to the laws of a simple age-dependent branching process. The expression forN(t) is obtained as a sum over all generations; thevth term of this sum, in turn, is a multiple convolution integral, reflecting the life history ofvth generation cells (i.e., the lengths of thev successive interdivision periods plus the age of the cell at timet). Assuming that cell volume is a given function of cell age, e.g., linear or exponential, and that cellular volume is exactly halved at each division, it is possible to calculate the volume of a cell with a given life history, and thus the average cellular volume of the whole population as a function of time. If at time zero the volumes differ from cell to cell, the final equation must be modified by averaging over initial volumes. In the case of linear volume increase with age, a very simple asymptotic expression is found for the average cellular volume ast→∞. The case of exponential volume increase with age also leads to a simple asymptotic formula, but the resulting volume distribution is unstable. The mean cellular volume at birth and the second moment of the volume distribution can be calculated in a similar manner.
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    Dynamic analysis, with feedback characterization, of hybrid human musculoskeletal frameworks by the linegraph-flowgraph procedure (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 499-520 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The dynamic response of human musculo-skeletal framework is treated by (i) idealization of the musculo-skeletal framework as hybrid structural networks possessing feedback characteristics and then (ii) employing linegraph-flowgraph procedures for the feedback characterization of the hybrid structural networks. Topological procedures are used in which a “tree” of a network furnishes the skeleton upon which the “linkage” (muscle representing) members provide interaction. Feedback characterization (representing the sensitivity of the skeletal members to the tensile forces) is defined, between the internal “linkage” and “tree” members, by means of the flowgraph. Mikusinski operational calculus is used to facilitate representation of inertia effects by dynamic feedback characterization, with inclusion of initial conditions.
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    Organismic supercategores: II. On multistable systems (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 539-561 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The representation of biological systems in terms of organismic supercategories, introduced in previous papers (Bull. Math. Biophysics,30, 625–636;31, 59–70) is further discussed. To state more clearly this representation some new definitions are introduced. Also, some necessary changes in axiomatics are made. The conclusion is reached that any organismic supercategory has at least one superpushout, and this expresses the fact that biological systems are multistable. This way a connection between some results of Rashevsky’s theory of organismic sets and our results becomes obvious.
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    On the mass distribution model for microbial cell populations (1970)
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    Bulletin of mathematical biology 32 (1970), S. 521-537 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The full implications of a statistical model for growth of a microbial cell population using cell mass as the index of physiological state have been examined by solving the partial differential integral equations resulting from the model. Calculations reveal that a lag phase is predicted during the initial stages of batch growth although no specific cellular mechanism for the phenomenon of lag had been incorporated into the model. The model predicts several situations of batch and continuous growth in which the population density and biomass concentration show opposing trends due to significant variation in the cell mass distribution with time.
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    Der Proteinbedarf des Rehes (Capreolus capreolus L.) zur Erhaltung (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 43-48 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Nitrogen (N) balance studies were performed with adult roe bucks in metabolism cages. The animals were fed pelleted diets. To a basic ration with 5.6% crude protein (CP) varving amounts of purified protein were added, raising the crude protein content up to 21.8% of the food dry matter. The N losses via the faeces were 6.1 g/kg of dry matter intake. At body weight equilibrium 94.5% of the apparently digested N were recovered in the urine. With the basic ration the urinary N excretion was down to 0.12 g/day/kg body weight0.75. Even with this diet, part of the animals achieved a positive N balance and raised the body weigh. A calculation of the requirements for maintenance of a roe deer of 20 kg body weight results in 7.5 g apparently digestible CP. With the experimental diet, this was equivalent to 24.3 g CP/day in the food or 5.5% CP in the food dry matter. These requirements are lower than those assumed for roe deer up to now, but are in good accordance with those known for domestic ruminants.
    Abstract: Résumé Des expériences de l'équilibre azoté avec des chevreuils adultes, tenus dans des cages de métabolisme, étaient fait. Comme nourriture unique ils recevaient de fourrage comprimé. À une ration de base pauvre en protéine (5,6% de protéine brute) nous ajoutions des quantités variables de protéine purifiée de soya, augmentant ainsi la teneur de protéine brute jusqu'à 21,8%. Les pertes de nitrogène par la fiente faisaient 6,1 g/kg de la matière sèche du fourrage. Au poids de corps constant, 94,5% de la nitrogène apparemment digestée étaient retrouvés dans l'urine. La ration de base pauvre en protéine reduisait l'excrétion urinaire de nitrogène à 0,12 g/jour/kg poids du corps0,75. Même avec cette diète-là les chevreuils étaient capables d'atteindre une balance de nitrogène positive et de prendre du poids. D'après ces résultats, les besoins quotidiens pour l'entretien s'élévent—chez un chevreuil de 20 kg—à 7,5 g de protéine brute apparemment digestible. Cela correspondait—avec la diète experimentale—à 24,3 g/jour protéine brute dans le fourrage ou à 5,5% de protéine brute dans la matière sèche. La quantité de la protéine nécessaire pour les chevreuils est plus petite que l'on a supposé jusqu'à présent. Elle s'accorde pourtant bien avec les besoins des ruminants domestiques.
    Notes: Zusammenfassung An ausgewachsenen Rehen wurden in Stoffwechselkäfigen Stickstoff-(N-)Bilanz-Versuche durchgeführt. Die Tiere bekamen pelletierte Alleinfutter vorgelegt. Eine proteinarme Basisdiät mit 5,6% Rohprotein (RP) in der Trockensubstanz wurde mit wechselnden Mengen gereinigten Sojaproteins verschnitten, so daß Diäten mit bis zu 21,8% RP entstanden. Die N-Verluste über den Kot betrugen 6,1 g/kg Futtertrockensubstanz. Vom scheinbar verdauten N wurden bei Gewichtskonstanz der Tiere 94,5% im Harn wiedergefunden. Bei der proteinarmen Basisdiät ging die Harn-N-Ausscheidung auf 0,12 g/Tag/kg Körpergewicht0,75 zurück. Auch mit dieser Diät waren die Rehe noch in der Lage, die N-Bilanz positiv zu gestalten und zuzunehmen. Der tägliche Bedarf zur Erhaltung bei einem Reh von 20 kg beträgt nach diesen Ergebnissen 7,5 g scheinbar verdauliches RP. Bei dem verwendeten Versuchsfutter entsprach das 24,3 g RP/Tag im Futter oder 5,5% RP in der Futtertrockensubstanz. Dieser Erhaltungsbedarf ist niedriger, als bisher für das Reh angenommen wurde, entspricht dagegen recht gut dem Bedarf von Hauswiederkäuern.
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    Gravidität der Gamsgaisen in den Julischen Alpen (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 50-53 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary From 1967 until 1973 in the Julian Alps of Slovenia 78 female chamois of various ages were examined for pregnancy. Of these 69 so-calledyeld females (those with no calves) were harvested as usual, while 9 females with calves were shot especially for the study. Both groups revealed a gravidity of 80%, based on all females in the third to 18th year of life. Some females in the third year of life were found to be pregnant, compared with nearly half of those in the fourth year of life. In middle-age females (4–10 years) gravidity was 90%, and 83% in older animals. 8% more corpora lutea were found in the ovaries than the number of embryos. Several such cases were examples of accessory forms, which means that double ovulation had occurred.
    Notes: Zusammenfassung In den Julischen Alpen Sloweniens wurden von 1967 bis 1973 78 erlegte Gamsgaisen verschiedenen Alters auf Trächtigkeit untersucht. Davon waren 69 als sog.Geltgaisen im Wege der Auslese abgeschossen worden. 9 kitzeführende aber speziell für die Untersuchungszwecke. Bei beiden Gruppen hatte die Trächtigkeit den gleichen Prozentsatz von 80, bezogen auf alle Gaisen vom dritten bis achtzehnten Lebensjahr. Im dritten Lebensjahr brunftete ein Teil der Gaisen erfolgreich (war trächtig), im vierten Lebensjahr etwas weniger als die Hälfte, im mittleren Alter (4–10 Jahre) lag die Trächtigkeit bei 90%, bei älteren Stücken bei 83%. Auf den Eierstöcken wurden 8% mehr Gelbkörperchen gefunden, als der Zahl der Embryonen entsprach. Bei einigen überzähligen Gelbkörperchen handelte es sich um atretische Formen, was bedeutet, daß die Gaisen zweimal ovulierten.
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    Fütterungsversuche mit Rebhühnern als Beitrag zur Frage der Ernährung des Rebhuhns in der Kulturlandschaft (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 57-59 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The results of studies of partridge in aviaries from 1968 to 1973 are reported. These results indicate that seeds are the only feasible winter fodder. Green feed is not necessary, as a rule. Seeds of the following plants were preferred by partridge:Ph. canariensis, Panicum sp.,Setaria sp.,Cannabis sativa, Phleum pratense, Lolium perenne, Agrostis alba gemcina. Seeds of the following wild herbs were infrequently selected:Atriplex sp.,Plantago sp.,Polygonum persicaria, Polygonum lapathifolium andRumex sp.
    Abstract: Résumé Il est fait état d'essais en volière avecPerdix perdix entre 1968 et 1973. L'alimentation hivernale n'est possible qu'au moyen d'une nourriture à base de grains. De la nourriture verte n'est pas fondamentalement nécessaire au cours de l'hiver. Sont préférées par la Perdrix les semences dePh. canariensis, dePanicum sp. etSetaria sp., deCannabis sativa, dePhleum pratense, deLolium perenne et d'Agrostis alba genuina. Les semences des espèces sauvages suivantes ne furent guère recherchées:Atriplex sp.,Plantago sp.,Polygonum persicaria etlapathifolium, Rumex sp.
    Notes: Zusammenfassung Berichtet wird über Volierenversuche mit Rebhühnern in den Jahren 1968 bis 1973. Aus den Versuchen wird gefolgert, daß die Winterfütterung von Rebhühnern allein auf Sämereienbasis möglich ist. Grünfutter ist im Winter grundsätzlich nicht notwendig. Bevorzugt werden vom Rebhuhn die Samen des Glanzgrases (Spitz,Ph. canariensis), der Hirse (Panicum sp.Setaria sp.), des Hanfes (Cannabis sativa), des Thimothes (Phleum pratense), des Deutschen Weidelgrases (Lolium perenne) und des weißen Straußgrases (Agrostis alba genuina). Kaum Zuspruch fanden die Sämereien verschiedener Wildkräuter wie Melde,Atriplex sp., Wegerich,Plantago sp., Floh- und pfirsichblättriger Knöterich,Polygonum persicaria bzw.lapathifolium und Sauerampfer,Rumex sp.
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    Rangordnung von Rehwild (Capreolus capreolus L.) an der Winterfütterung in einem schweizerischen Jagdrevier (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 53-56 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary In the winter of 1972/73 the rank-order of individually marked roe deer at an artificial feeding site was studied in the foothills of eastern Switzerland. The observed rank-order was almost linear and more or less stable throughout the winter. The only drops in rank were caused by casting of antlers and impairment through injury, whereas cleaning of antlers raised a buck's rank. Adult bucks dominated all other classes, and male fawns dominated almost all females The effects of age, antler size, distance from summer territory, and duration of stay in the feeding site area on rank were tested by rank correlations. In adult bucks, only distance from summer territory affected rank significantly, bucks from the vicinity being the most dominant. This result and the fact that the dominant bucks, who alone showed marking behaviour, were the most aggressive, suggest that roebucks are potentially territorial also in winter. Does were the higher in rank the earlier they were first observed visiting the feeding site, i.e. the more familiar they were with it. The rank of females was not affected by age. Occupied piles of food were sometimes successfully defended against higher ranking individuals.
    Abstract: Résumé En hiver 1972/73 le comportement agonistique et la hiérarchie sociale des chevreuils individuelement marqués fut examiné à une place à fourrage dans une chasse préalpine en Suisse. La hiérarchie était linéaire et ordinairement stabile. Des changement en hiérarchie sociale furent observés après la jeter et l'écurer des bois et après des blessures. Les brocards adultes dominaient toutes les autres classes. L'influence fut examiné avec des correlations de rang entrele rang et l'âge, la grandeur des bois, la distance entre la place à fourrage et le territoire en été, la première date d'observations à la place à fourrage. Le rang des brocards adultes est influencé de manière negative significante seulement par la distance: le plus près un brocard a son territoire en été, le plus il est dominant. Ce fait et le fait, que seulement les brocards des deux premiers rangs étalent un comportement de marquer laissent présumer qu'un comportement territorial éxiste en hiver aussi. Les femelles adultes n'étaient pas influencées par l'âge; mais le plus tôt qu'elles viennent à la place à fourrage en hiver le plus elles sont dominantes.
    Notes: Zusammenfassung Im Winter 1972/73 wurde das agonistische Verhalten und die Rangordnung von individuell markierten Rehen an einer Winterfütterung in den Voralpen der Ostschweiz untersucht. Die Rangordnung war beinahe linear und mehr oder weniger stabil. Rangverlust wurde nach Geweihabwurf und Verletzung, Ranggewinn nach Fegen des Geweihs beobachtet. Adulte Böcke dominierten alle anderen Klassen, und Kitzböcke dominierten fast alle Geißen. Die Beziehung zwischen Rang und Alter, Geweihgröße, Distanz zwischen Futterstelle und Sommereinstand sowie erstem Beobachtungsdatum an der Winterfütterung wurde mit Rangkorrelationen geprüft. Bei adulten Böcken hatte nur die Distanz zum Sommereinstand einen Einfluß auf die Ranghöhe: je kürzer diese Distanz, desto dominanter der Bock. Dies und die Tatsache, daß die ranghöchsten Böcke am aggressivsten waren und als einzige Markierverhalten zeigten, legt die Vermutung nahe, daß Rehböcke auch im Winter potentiell territorial sind. Geißen waren um so ranghöher, je früher sie erstmals an der Winterfütterung beobachtet worden waren. Dagegen hatte das Alter keinen Einfluß auf die Ranghöhe. In Besitz genommene Futterhaufen wurden manchmal erfolgreich gegen ranghöhere Tiere verteidigt.
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    Pesticid- und PCB-Rückstände in Organen von Wildtieren als Indikatoren für Umweltkontamination (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 70-74 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary During the years 1970 to 1973 we investigated 800 samples of organs, adipose tissue and eggs from 26 wild animals species gaschromatically in respect of chlorinated pesticides and Polychlorinated Biphenyls. The most abundant pesticides were HCB and Lindane + Isomeres (Tab. 1). The pesticide- and PCB-concentrations in liver- and fat tissue of herbivores were about five times lower (ppb-values) than we found in carnivores, where the residues accumulated according to the nutrition chain (Tab. 2 and 3). The highest values we got from eggs of predatory birds and from codfish liver (ppm-values Tab. 2 and 3; for instance DDE and DDT + isomeres).
    Abstract: Résumé Au cours des années 1970 à 1973, 800 échantillons d'organes, de dépôts de graisse et d'oeufs, prélevés sur 26 espèces d'animaux sauvages, ont été analysés par chromatographie gazeuse en ce qui concernait leur teneur en pesticides chlorés et en PCB. Le PCB et les isomères du Lindane étaient les résidus les plus répandus (plus de 90%) (Tableau 1). Chez les Herbivores, la concentration en pesticide et en PCB dans le foie et dans les tissus de graisse était de l'ordre du ppb (Tableaux 2 et 3). Les plus hautes teneurs en résidus — DDE, DDT, et ses isomères, notamment — furent relevées dans les oeufs de Rapaces et dans les foies de Morue (de l'ordre du ppm) (cfr Tableaux 2 et 3).
    Notes: Zusammenfassung Während der Jahre 1970 bis 1973 wurden 800 Organ-, Fett- und Eierproben von 26 Wildtierarten gaschromatographisch auf Rückstände an chlorierten Pesticiden und PCBs hin untersucht. Mit über 90% waren HCB und Lindan + Isomere am verbreitetsten (Tab. 1). Die Pesticid- und PCB-Konzentration im Leber- und Fettgewebe lag bei Herbivora im ppb-Bereich (Tab. 2 und 3), stieg jedoch im Rahmen der Nahrungskette bei Carnivora auf das Fünffache der bei Pflanzenfressern gefundenen Werte (Tab. 2 und 3). Die höchsten Rückstandsmengen-v.a. an DDE, DDT und Isomeren-fanden wir in Greifvogeleiern und in Dorschleber (ppm-Bereich siehe Tab. 2 und 3).
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    Referate (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 80-84 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    Jahrestreffen der Arbeitsgemeinschaft jagdlicher Forschungsstätten (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 79-79 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    Der ökonomische Wert der Wildproduktion in Europa (ohne Sowjetunion) (1974)
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    European journal of wildlife research 20 (1974), S. 85-95 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    Professor Fritz Nüßlein zur Vollendung des 75. Lebensjahres (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 119-120 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    Institut und Lehrkanzel für Wildbiologie und Jagdwirtschaft an der Hochschule für Bodenkultur in Wien geplant (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 120-120 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    Referate (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 120-124 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 180
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    Beitrag zur Altersbestimmung beim Rotfuchs (Vulpes vulpes L., 1758) (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 96-104 
    Details
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Two methods for estimating age were applied on 1655 red foxes (871 males, 591 females and 193 of undetermined sex), 290 of which were found to be rabid. The first method uses age of teeth (cutting, shedding and attrition) as an indication to the age of the animal. The second (developed byvan Haaften [1969]) involved the dry weight of eye lenses. A comparison of the methods revealed that both were equally reliable for animals up to the age of two years. Neither method proved to be satisfactory for estimating age in adult animals, although the dry weight method seems to be the more informative one. The range in the dry weight of eye lenses is shown in table 5 for animals from 2 months to 2 years in graph 1 for animals up to 8 years. Graph 2 illustrates the relationship between age, dry weight of eye lens, and age of teeth.
    Abstract: Résumé 1655 renards—871 mâles, 591 femelles et 193 de sexe non déterminé—dont 290 sujets se sont avérés atteints par la Rage, ont fait l'objet d'une étude comparative sur les méthodes de détermination de leur âge par analyse de la dentition (émergence des dents, remplacement et degré d'usure) et par pesée du cristallin (van Haaften 1969). Des résultats satisfaisants ont été obtenus au moyen des deux méthodes jusqu'à l'âge de deux ans. Chez les sujets plus âgés, la méthode par examen de la dentition est impropre à une détermination correcte. En raison du manque de possibilités de comparaison avec des sujets d'âge connu, l'application de la méthode par pesée du cristallin à des sujets de plus de deux ans reste sujette à caution, mais cette méthode semble toutefois plus efficace que les autres. Le Tableau 5 donne le degré de variation des poids secs du cristallin de renards âgés de deux mois à deux ans. La figure 1 visualise ce degré de variation jusqu'à l'âge de 7 ans. La figure 2 permet la comparaison des pyramides des classes d'âge obtenues en appliquant les deux techniques de détermination.
    Notes: Zusammenfassung 1655 Rotfüchse—871 Rüden, 591 Fähen und 193 ohne Geschlechtsbestimmung—von denen sich durch die Laboruntersuchungen 290 als tollwütig erwiesen, wurden nach dem Zahnalter (Zahndurchbruch,-wechsel und-abnutzung) sowie auf Grund des Linsentrockengewichts nach der Methode vonvan Haaften (1969) auf ihr Alter untersucht und die beiden Methoden miteinander verglichen. Beide Arten der Altersfeststellung liefern für Jungfüchse und Altfüchse bis zu 2 Jahren verläßliche Ergebnisse. Bei älteren Füchsen versagt die Zahnaltersbestimmung. Auf Grund mangelnder Vergleichsmöglichkeiten mit Füchsen bekannten Alters läßt sich zwar über die Sicherheit der Altersbestimmung mittels Linsentrockengewicht bei älteren als 2jährigen Füchsen noch keine endgültige Aussage machen, doch erscheint die Methode aufschlußreicher als die anderen Arten der Altersbestimmung. Tabelle 5 gibt die ermittelten Schwankungsbreiten der Augenlinsentrockengewichte bei Füchsen von 2 Monaten bis 2 Jahren an, die in einer graphischen Darstellung (Abb. 1) bis zum 8. Lebensjahr fortgeführt wird. In einer weiteren Graphik (Abb. 2) werden die Alterspyramiden nach Linsentrockengewicht und Zahnalter gegenübergestellt.
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    Beitrag zur Kenntnis des Endoparasitenspektrums des Gemswildes in der Schweiz (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 115-118 
    Details
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Organs of six chamois originating from two subalpine areas in Switzerland were examined. 18 different species of nematodes were found in the digestive tract (namelyTrichostrongylus axei, Ostertagia circumcincta, O. leptospicularis, O. trifurcata, Marshallagia marshalli, Skrjabinagia kolchida, S. lyrata, Rinadia mathevossiani, Spiculopteragia böhmi, Haemonchus contortus, Trichostrongylus capricola, Cooperia oncophora, Nematodirus filicollis, N. helvetianus, Trichuris ovis, Oesophagostomum venulosum andChabertia ovina) and two additional species in the lungs (Protostrongylus rupicaprae andMuellerius capillaris). Two out of five animals examined were infected withEimeria spp. and three out of four animals withSarcocystis sp. The examination of 213 lungs of chamois from the cantons of Appenzell-Innerrhoden, Schwyz and Lucerne revealed 114 cases of protostrongylidoses due toProtostrongylus rupicaprae andNeostrongylus linearis and one case of dictyocaulosis. It is assumed that the trichostrongylid fauna of the chamois overlaps to a considerable extent with that of domestic ruminants, roe deer and red deer.
    Abstract: Résumé Des examens parasitologiques pratiqués chez six chamois du Jura d'Argovie et du Tössstock dans le Canton de Zurich ont mis en évidence 18 espèces de Nématodes du tube digestif (à direTrichostrongylus axei, Ostertagia circumcincta, O. leptospicularis, O. trifurcata, Marshallagia marshalli, Skrjabinagia kolchida, S. lyrata, Rinadia mathevossiani, Spiculopteragia böhmi, Haemonchus contortus, Trichostrongylus capricola, Cooperia oncophora, Nematodirus filicollis, N. helvetianus, Trichuris ovis, Oesophagostomum venulosum etChabertia ovina) et deux autres espèces dans les poumons (Protostrongylus rupicaprae etMuellerius capillaris). Deux animaux sur cinq étaient parasités parEimeria spp., trois sur quatre parSarcocystis. Sur 213 poumons examinés de chamois provenants des Cantons Appenzell-Innerrhoden, Schwyz et Lucerne 114 présentaient une infestation par des Protostrongylidés (Protostrongylus rupicaprae etNeostrongylus linearis) et 1 une infestation parDictyocaulus. On peut remarquer que la faune des Trichostrongylidés rencontrée chez les chamois est très proche de celle observée chez les ovins, caprins, bovidés domestiques ainsi que chez les chevreuils et cerfs d'Europe.
    Notes: Zusammenfassung Bei sechs Gemsen aus dem Aargauer Jura und dem Tösstock im Kanton Zürich wurden 18 Nematodenarten im Magen-Darmtrakt und 2 weitere Arten in der Lunge gefunden. Bei 2 von 5 Tieren lag ein Befall mitEimeria spp. vor, 3 von 4 Tieren waren mitSarcocystis sp. infiziert. Von 213 Gemslungen aus den Kantonen Appenzell-Innerrhoden, Schwyz und Luzern wiesen 114 Protostrongyliden- und 1 Dictyocaulus-Befall auf. Es wird festgestellt, daß bei der Trichostrongylidenfauna der Gemse weitreichend Überschneidungen mit den Artenspektren bei Schaf und Ziege, Rind, Reh und Rotwild bestehen.
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    Der parasitologische Zustand von Gemspopulationen des schweizerischen Juras im Vergleich zu Alpengemsen (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 105-115 
    Details
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Between the years 1970 and 1972 58 Swiss chamois (Rupicapra rupicapra L.) from the Jura mountains were studied for parasites. They were collected within the region Waldenburg — Olten — western Weißenstein (canton Basel-Landschaft and Solothurn) and in the Chasseral (canton Berne). Originally they had been transferred from the Swiss Alps to the Jura, where they were acclimatized. The following endoparasites were found: 3 lungworms, 8 gastro-intestinal nematodes (in some cases the species was not identified), 1 trematode, 2 cestodes and coccidia. The extensity and intensity of the species found were compared with two studies from Austria, and, in the case of lungworms, with a Swiss and a German report as well. Parasitic intensity and extensity seem less in the Bernese than in the Basel-Land and Solothurn Jura mountains. But in the entire Jura they are found to a lesser extent than in the reported regions of the Alps; sometimes this difference is very clear (exception:Protostrongylus in the cantons Basel-Landschaft and Solothurn). From the limited parasitic intensity and the low death rate among the Jura chamois it can be concluded that the Jura mountains are a favourable environment for these animals; there seems to be no overpopulation effect. The limited parasitic extensity as well suggests that the chamois population is not too dense; in addition the biotope appears unfavourable for the free-living stages of the parasites and the influence of a contact between chamois and domestic animals unimportant. The range of species found on this study was as to be expected.
    Abstract: Résumé Pendant les années 1970–1972 des recherches parasitologiques ont été faites sur le chamois (Rupicapra rupicapra L.) dans le Jura Suisse. 58 chamois, capturés dans la région de Waldenburg — Olten — partie ouest du Weissenstein (canton de Bâle-campagne et de Soleure) et du Chasseral (canton de Berne) ont été examinés. Toutes ces populations proviennent de quelques animaux introduits des Alpes Suisses. Les endoparasites trouvés sont les suivants: trois nématodes bronchiques, 8 nématodes gastro-intestinaux (qui n'ont pas tous été déterminés jusqu'à l'espèce), un trématode, deux cestodes et des coccidies. La fréquence et l'intensité des atteintes ont été comparées avec celles décrites dans deux travaux autrichiens. Les résultats sur les vers bronchiques ont en outre été comparés avec ceux présentés dans une publication suisse et allemande. Intensité et fréquence des atteintes semblent être un peu plus faibles dans le Jura bernois que dans le Jura soleurois et de Bâle-campagne. En tout cas elles sont plus faibles que dans les régions alpines qui nous servaient de comparaison. (Il existe une exception chezProtostrongylus dans les cantons de Bâle-campagne et de Soleure.) La faible intensité des atteintes et le fait qu'on trouve rarement des animaux péris mène à la conclusion que l'état sanitaire général des chamois jurassiens est assez bon. Selon toute vraisemblance la qualité du biotope jurassien convient au chamois et sa densité n'est pas exagérée. En outre, la faible fréquence des parasites affaiblit l'idée d'une surpopulation du chamois et laisse supposer que le biotope n'est pas favorable aux parasites pendant leur développement à l'exterieur de l'hôte. Le contact avec des bêtes domestiques, fréquent dans certaines régions du Jura, ne semble pas jouer un rôle important. Le nombre des espèces ne differt pas de ce que l'on pouvait attendre.
    Notes: Zusammenfassung In den Jahren 1970–1972 wurden an 58 Schweizer Juragemsen (Rupicapra rupicapra [L.]) aus dem Raume Waldenburg — Olten — westlicher Weißenstein (Kantone Basel-Landschaft und Solothurn) und Chasseral (Kanton Bern) parasitologische Untersuchungen durchgeführt. Die untersuchten Tiere stammen alle aus Populationen, die auf Aussetzungen von Gemsen aus den Schweizeralpen zurückgehen. An Endoparasiten wurden drei Lungennematoden, acht Magen-Darmnematoden (teilweise nicht bis auf die Art differenziert), ein Trematode, zwei Cestoden und Coccidien nachgewiesen. Die Befallsextensitäten und-intensitäten wurden mit zwei Untersuchungen aus Österreich verglichen, im Falle der Lungenwürmer zusätzlich mit einer schweizerischen und einer deutschen Arbeit. Befallsintensität und-extensität scheinen im Bernerjura etwas geringer zu sein als im Baselbieter- und Solothurnerjura. An beiden Orten sind sie, teilweise sehr eindeutig, niedriger als in den Vergleichsgebieten der Alpen. (Ausnahme:Protostrongylus in den Kantonen Basel-Landschaft und Solothurn.) Aus der geringen Intensität und dem seltenen Auftreten von Fallwild wird geschlossen, daß die Kondition der Juragemsen gut ist. Das könnte auf Eignung des Juras als Gemshabitat und auf das Fehlen von Übervölkerungseffekten hinweisen. Die geringe Extensität läßt ebenfalls nicht überhöhte Dichte vermuten, zusätzlich einen für die freien Parasiten ungünstigen Biotop und einen geringen Einfluß des vorhandenen Kontaktes mit Haustieren. Das Artenspektrum liegt im Rahmen des zu Erwartenden.
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    Papillomatose bei einem Damhirsch (Cervus dama L. 1758) (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 157-158 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Papillomatosis was found in the praeputium of a male Fallow-deer.
    Abstract: Résumé Il est décrit un cas de papillomatose chez le daim dans la region du praeputium.
    Notes: Zusammenfassung Es wird über einen Fall von Papillomatose im Bereich des Praeputium bei einem freilebenden Damhirsch berichtet.
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    Fruchttod beim Reh (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 159-161 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary A case of maceration of a fetus in the vagina of roe deer is reported.
    Abstract: Résumé Il est décrit la maceration d'un fetus dans la vagine chez le chevreuil.
    Notes: Zusammenfassung Es wird über eine Beobachtung von Fruchtmazeration in der Vagina beim Reh berichtet.
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    Mißbildung an Rehbockschädel (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 161-162 
    Details
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The formation of a bone case on the right half of a roe deer cranium is described, which is probably the result of a slow growing tumour.
    Abstract: Résumé Description d'une excroissance osseuse sur la partie doite du crâne causée vraisemblablement par le développement progressif d'une tumeur.
    Notes: Zusammenfassung Beschrieben wird die Ausbildung einer Knochenkapsel an der rechten Schädelhälfte eines Rehbockes, die vermutlich durch eine langsam wachsende Geschwulst entstanden ist.
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    Dreiwurzlige Praemolaren bei Rotfüchsen (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 163-165 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Amongst 4 of 488 Red Foxes (Vulpes vulpes L.) from the Canton of Berne (Switzerland), 5 Premolars with a third lateral root have been found (4 times in P2, 1 time in P4). Time and place of killing point to a genetic connection. Ecological aspects are discussed.
    Abstract: Résumé Chez 4 parmi 488 renards (Vulpes vulpes L.) du canton de Berne (Suisse), il y avait 5 prémolaires avec une troisième racine latérale (4 fois chez P2, 1 fois chez P4). Lieu et date des tirs indiquent une relation génétique. Des aspects écologiques sont discutés.
    Notes: Zusammenfassung Bei 4 von 488 Füchsen aus dem Kanton Bern (Schweiz) fanden sich 5 Prämolaren im Unterkiefer mit einer dritten lateralen Wurzel (viermal bei P2, einmal bei P4). Zeit und Ort der Abschüsse weisen auf eine genetische Verbindung hin. Ökologische Aspekte werden diskutiert.
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    Mallophaga in der Federspule des Auerhuhns (Tetrao urogallus L.) (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 165-169 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Two unusual finds ofGoniodes sp. are described in the present paper. In the first capercaillie cook, 8 specimens ofGoniodes sp. were found within the quill cavity of the 10th primary just moulted (Fig. 1, 2). A facultative occurrence of the respective Mallophaga in such an uncommon milieu follows from the finds of its excrements and of the damaged interior of the quill. Bloody remains of mesodermal tissue filling the cavity of quills in two middle rectrices and in one secondary respectively were found on another cock shot not far from the place of the foregoing observation. In this latter case, a blood consumation byGoniodes sp. is presumed in some of living larvae as well as of adults according to the colour of their intestine (Fig. 3, 4).
    Abstract: Résumé On rend compte de la découverte de 8 exemplaires deGoniodes sp. dans le calamus d'une des 10ièmes rémiges primaires, récemment muée, d'un Grand Tétras (figures 1 et 2). L'examen des matières fécales et des septa distaux du calamus interne atteint milite en faveur d'une colonisation facultative deGoniodes sp. dans un site aussi inhabituel. Dans un autre Grand Tétras tiré à proximité on a constaté que les septa du calamus interne avaient été ensanglantés au niveau des deux rectrices médianes et dans une rémige secondaire. La couleur du conduit intestinal de certaines larves et imagos indique qu'ils se sont nourris de sang (figures 3 et 4).
    Notes: Zusammenfassung Es wird ein Fund von 8 ExemplarenGoniodes sp. in der Federspule einer frisch gemauserten 10. Handschwinge eines Auerhahnes beschrieben (21. 5. 1972 Abb. 1, 2). Der Kot und die beschädigte Federseele sprechen für ein fakultatives Besiedeln dieses für die o. g. Gattung abnormalen Lebensraumes. Ein anderer unweit des ersten Fundortes erlegter Auerhahn hatte eine blutige Federseele in den zwei mittleren Stoßfedern und einer Armschwinge; bei einigen Larven und VollkerfenGoniodes sp. deutet die Farbe des Darmkanals auf Blutaufnahme (13. 5. 1973 Abb. 3, 4).
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    Übereinstimmungen in der Gehörnform beim Rehbock (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 207-209 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The similarity of antler form, which can repeat itself for decades in a small region, is illustrated with the help of 4 photographs.
    Abstract: Résumé On relève, avec quatre documents photographiques à l'appui, les analogies de la forme des bois qui se sont reproduites sur un espace fort exigu, parfois au-delà de plusieurs dizaines d'années.
    Notes: Zusammenfassung An Hand von 4 Photos wird auf Ähnlichkeiten in der Gehörnform hingewiesen, die sich zum Teil nach Jahrzehnten auf engstem Raum wiederholten.
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    Dr. Heinrich Wolf 65 Jahre (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 215-215 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Type of Medium: Electronic Resource
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    Zur Altersbestimmung beim Feldhasen (Lepus europaeus Pallas) (1974)
    Springer
    European journal of wildlife research 20 (1974), S. 209-212 
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    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Three measurements were taken on each of 25 lower jaws of hare to estimate the possible interdependence in growth in length of the jaw, the tooth, and in width of the oral cavity. The date were not sufficient to establish clearly an age dependence, but a high probability points in this direction. This work will hopefully instigate further collection of data to enable age-estimation with the aid of age-dependent growth factors.
    Abstract: Résumé Trois mensurations (croissance en longueur du maxillaire inférieur, croissance en longueur des dents et croissance en largeur de la cavité dentaire) ont été effectuées sur les maxillaires inférieurs de 25 lièvres en vue de relever d'éventuelles corrélations avec leur âge. Malgré l'insuffisance du matériel examiné, une relation hautement probable a pu être mise en évidence. Ce travail devrait inciter les milieux cynégétiques à recueillir un matériel plus abondant qui permettrait d'élaborer une méthode de détermination de l'âge sur la base de ces relations biométriques.
    Notes: Zusammenfassung An 25 Unterkiefern von Hasen wurden drei Meßwerte zum Längenwachstum des Unterkiefers, zum Längenwachstum des Zahnes und zum Breitenwachstum der Zahnhöhle auf ihre möglichen Abhängigkeiten zum Alter überprüft. Für eine exakten Nachweis der Altersabhängigkeit reichte das Material nicht aus, aber die hohe Wahrscheinlichkeit der Abhängigkeit konnte doch erhärtet werden. Durch diese Arbeit sollen größere Kreise veranlaßt werden, weiteres Kiefermaterial zu sammeln, um Abhängigkeiten nachweisen und zu einer Altersbestimmungsmethode ausbauen zu können.
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    Traitement des informations chez les etres vivants: Systemes a services par essais successifs (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 83-148 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Information treatment, especially in a natural medium, may be done by a random system: given an input, possible solutions are randomly selected and successively tested until the right one is found and then emitted. This paper is a mathematical study of this type of system and its use as a model of some natural (biological) systems. The theoretical development is illustrated by several examples of possible applications to biological cases. We study, under different assumptions, the distribution of the number of trials needed to treat the input, the distribution of the time for this treatment, and the distribution of the average amount of information treated in a trial or in a unit of time. We consider the case of error, and study some optimal conditions of operation and the occurrence of memory influencing the treatment of an input according to previously processed inputs.
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    Energy of nerve impulse (1970)
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    Bulletin of mathematical biology 32 (1970), S. 151-153 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
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    Comments concerning P. C. Voukydis’ “Physiological significance of the geometrical shape of the left ventricle: Course and curvature of the individual myocardial fibers” (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 149-149 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02476797
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  • 194
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    Mathematical biology of automobile driving: V (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 173-178 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The role of some inertial properties of the car, studied previously only for the case when the stimulus for the corrective turn is the perception of the angle between the direction of the car and the direction of a straight lane (Bull. Math. Biophysics,32, 71–78, 1970), is generalized to include such stimuli as the nearness to the edge of the lane and the anticipatory effect for a corrective turn, as well as the combination of all three stimuli. Conditions for stability of driving are deduced and discussed. They now depend on both biological parameters and such parameters as the position of the center of gravity of the car, its mass, and the side slip of the tires.
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    URL: http://dx.doi.org/10.1007/BF02476883
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  • 195
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    Definition d’une distance entre deux mobiles se deplacant de facon aleatoire sur une droite (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 179-195 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Description / Table of Contents: Résumé Pour le biologiste, la notion dedistance entre deux ou plusieurs éléments d’un ensemble est très utile car elle sert à mesurer laproximité, laparenté, laressemblance qui existe entre ces éléments ou parties selon le caractère auquel on s’intéresse (position géographique, situation chronologique, aptitudes, phénotypes, composition chimique etc...).
    Notes: Abstract Adistance between two mobiles performing a random walk in one dimension is defined. At a given time this distance is directly related to theprobability of encounter for the mobiles. This definition is used when the motion of the mobiles is a Wiener-Levy process, first in the case of an unrestricted random walk, then if a reflecting or absorbing barrier is introduced.
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    URL: http://dx.doi.org/10.1007/BF02476884
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    Effects of anisotropy and nonhomogeneity on left ventricular stresses in the intact heart (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 197-213 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract The qualitative effects of anisotropy and nonhomogeneity are considered in the evaluation of left ventricular stresses in the intact heart. Maximum stresses and their location are significantly dependent on the nonhomogeneity factors and to a lesser degree on anisotropy of the ventricular wall material. If the circumferential elastic modulus is assumed to vary in a parabolic manner through the wall thickness, maximum stresses occur within the endocardial layers, a result in qualitative agreement with experimental studies.
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    A correction for the effect of the dead space in pulmonary gas washout tests (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 215-218 
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    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Under the assumption that there is complete mixing in the dead space a series of equations are given which give the values for a washout test of the functional component of the pulmonary bellows (without a dead space) in terms of the washout values of the bellows with a dead space.
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  • 198
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    Respiration of tissue as a medium of heterogeneous permeability (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 219-235 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Expressions are derived for the overall oxygen consumption and the O2 penetration depth into a tissue section in terms of the basic parameters, of the system under steady-state conditions. The approach differs from many previous analyses in so far as the oxygen molecules are regarded as reaching their sites of chemical assimilation by diffusion through extracellular fluid followed by bulk diffusion into irregular cells of significantly lower permeability. This “two-phase” model would seem to be compatible with the major experimental features of steady-state respiration, and gives a ratio of cellular to extracellular diffusion coefficients of the same low order as that found for inert gases under transient conditions. The greater oxygen penetration predicted by this model is discussed in relation to the survival of ischemic tissue and is shown to be consistent with data for myocardial infarction.
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    URL: http://dx.doi.org/10.1007/BF02476887
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    Analytical solutions for the specific activities of a traced substance within the component parts of a simulated kidney-ureter system (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 263-278 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Two models for a kidney-ureter system are considered: one model of one vessel in which a traced substance, undergoing exchange between the vessel and an external compartment, is emptying into the ureter; the second model of two approximately parallel, identical vessels in which a traced substance, undergoing exchange between each vessel and an external compartment, is emptying into the ureter. A single impulsive input of label into a vessel is assumed. For mathematical simplicity, the major conditions imposed on each system are: (1) rapid mixing transverse to a vessel axis and no mixing longitudinal to a vessel axis within the plasma; (2) small variation of the specific activity within the plasma in the longitudinal direction to a vessel axis; (3) constant flow rate of urine into the ureter and (4) constant exchange coefficients, tubule flow velocity and traced substance concentrations within individual compartments.
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    The motion of the left ventricle—III (1970)
    Springer
    Bulletin of mathematical biology 32 (1970), S. 279-291 
    Details
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract We use the concept of a layered wall, where each separate layer is to be homogeneous, isotropic, and incompressible, to derive stress-strain relations for the middle layer muscle ring at the transverse midsection of the left ventricle; a convenient method of formulation is that based on the elastic potential function. The hoop or circumferential stress in all three layers is found using dimensional and mechanical parameters derived earlier. The various parameters are expressed as Fourier series so that their behavior over a complete ventricular cycle is known analytically. The cases of simple elongation and what we termcurvilinear simple elongation are considered for the middle layer muscle ring strain, and the resulting stress-strain relations are derived. The results are compared with an incompressible rubber-like material known as a Mooney material.
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    URL: http://dx.doi.org/10.1007/BF02476891
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